Microsoft word - physiologie etc. diss. 1995-2004 eng.doc

Bäcker, Natalie (2003):
Effect of an oral supplementation with L-argininehydrochloride on bone metabolism of
healthy postmenopausal women.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 113 pages.
Introduction: Recent experimental studies indicate that nitric oxide (NO) is an important
regulator of bone turnover by exerting an anabolic effect on bone cell activity. The NO-level
of the human body can be elevated through application of pharmacological NO-donors. The
first human trials conducted showed a positive effect of an NO-donor application on the
metabolism of human bones. On the other hand L-arginine, the natural precursor of NO-
synthesis, is also able to enhance NO-production and, in contrast to NO-donors, seems -in
amounts to 30 g- to be free of undesirable effects. Furthermore, an oral L-arginine
supplementation causes a significant increase in IGF 1 release, which also has a positive
effect on bone metabolism. The purpose of this study was to examine the effect of a six-
month daily oral supplementation with 18 g L-argininehydrochloride on the bone metabolism
of healthy postmenopausal women.
Method: Thirty healthy postmenopausal women, divided into two groups, took part in this
study. One group (54.5 ± 4.1 years, 66.3 ± 10.5 kg) received a six-month daily oral
supplementation with 18 g L-argininehydrochloride (i.e. 14.8 g free L-arginine). The other
fifteen volunteers (55.3 ± 4.4 years, 64.2 ± 9.1 kg) obtained 18 g dextrose as placebo. To
eleminate exogen influencing factors the volunteers were asked not to change their activity
or eating behavior during the study. For checking purposes nutritional intake and physical
activity were documented in protocols during the study. 24-hour urinary excretion of nitrogen,
as an indicator for compliance, was analysed for two days at baseline and after two, four and
six months. For the analysis of IGF 1, bone formation markers PICP, bAP, osteocalcin, the
bone resorption marker CTX as well as for parathyroid hormone and serum-calcium blood
was drawn at baseline and after two, four and six months of supplementation. pQCT
measurements were performed at trabecular and cortical sites of radius and tibia at baseline,
after six months and after one year.
Results: Volunteers did not change their eating behavior or physical activity during the six
months of intervention. As expected, nitrogen excretion rose in the group with
L-argininhydrochloride supplementation and remained constant in the placebo group.
Biomarkers of bone metabolism did not change following the L-argininehydrochloride
supplementation. The results from the pQCT-measurement showed a change at cortical
bone site of the radius in the L-arginine group, but no significant changes were observed at
any other site. A change in IGF 1 concentration due to the L-argininhydrochloride
supplementation was also not evident.
Conclusion: The results show that a supplementation with L-argininehydrochloride is not as
effective as an application of NO-donors to influence bone metabolism of postmenopausal
women. Alone the cortical thickness of the radius showed a significant increase due to the
supplementation. Furthermore in view of the fact that no change in IGF 1 concentration was
observed, it was evident that there could be no IGF 1 dependent influence on bone
metabolism. Therefore potential factors, which led to the reduced effect, should be checked
in following studies, to intensify the impact of the amino acid L-arginine on bone metabolism.

Berns, Georg (1996):
Integration of check-lists and mobile lab into a consulting system to extend preventive
herd health- and quality programmes in pig production.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 198 pages.
The objective of the work at hand is to organize a consulting system oriented towards
information and method needs of the pig production farm and, for this purpose, to integrate
the use of a mobile lab.
In the work presented here, at first the recorded data like biological performance, feeding,
slaughtering and economic data are categorized. At second, the new data catagories
"environment data" and "health data" are added. For systematically recording environmental
data three types of check-lists for piglet-production, piglet breeding and pig-fattening farms
are used.
The use of the check-lists was tested in empirical tests. The characteristic farm numbers and
parts of characteristic farm numbers found were compared with biological performance data
and slaughter data for correlation in order to find the probability that disturbances can be
correctly evaluated through the evaluation system.
The validation revealed significant coefficients of correlation of r = 0,49 to r = 0,80 between
characteristic farm numbers and reference data.
The results show that the inspection and measuring parameters in check-lists and the
calculated partial characteristic farm numbers are appropriate to find the disturbed processes
and critical points in production. The calculated farm and partial characteristic numbers lead
to a ranking of the farms and farm parts. With the mobile lab and the measured values and
calculated characteristic numbers it is possible to carry out process control and determine
alarm and limit values. When these values are reached, measures have to be taken.
Following the test use of the mobile lab within existing consulting organisations and quality
management systems that encompass the production chain, intervention in the following
areas can be suggested in order to extend health control during production:
Critical point analysis within extended traditional production consulting externally organized
intermediate control in the sense of quality management systems on the farm's or chain's
leve.
Support in the choice of suppliers and their regular assessments within chain-encompassing
quality management systems.
Finkler - Schade, Christa (1997):
Field study during the grazing season on the nutrition of lactating mares and suckling
foals as well as on the growth of the foals.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 253 pages.
The purpose of this field study was to estimate the provision with energy and nutrients of 149
lactating mares and their suckling foals during the grazing season. From April to October
1993, the feeding in 40 Westphalian breeding farms was recorded and samples of pasture
grass, forages and oats were taken. They were analysed for nutrients including macro- (Ca,
P, Mg, Na, K) and microelements (Fe, Cu, Zn, Mn) and the values were used for ration cal-
culations. The results of the ration calculations were then compared with the
recommendations for the provision with energy and nutrients (GFE, 1994). They were
expressed as deviation from the recommendations in per cent. A total of 630 rations for the
lactating mares and 346 rations for the foals was calculated. The results were divided into
horses with pasturing and supplementary feeding and horses only with pasturing without
supplementary feeding. The results of the ration calculations show some enormous
deviations from the recommendations for the mares as well as for the foals. For the lactating
mares of both feeding groups the excess of digestible protein and potassium stands out, that
applies also to the zinc deficiencies of the rations without supplementary feeding. The
deficiencies in the supply of the foals, independent from the feeding management, with the
minerals calcium, phosphorus, magnesium, copper and zinc also stand out.
Additionally, the growth of the 149 foals during the first 6 months of life was registered every
five weeks. The following body measurements were taken: height at withers, tape-measure,
length of cannon bone, circumference of cannon bone and fetlock joint, length of body and
girth. The growth rates show intensive growth in the first months and reduce continuously
with advancing age. Around the 5th month of life a distinct growth spurt can be observed for
all body measurements.
The multiple linear regression analysis about the influence of age and nutrition of the foals on
growth results in a high R square of about 0.42 for the height at withers. In the regression
model the calcium shows a positive influence on growth rate, on the other hand age and the
elements sodium, potassium and manganese show a negative influence.
The foals were also judged for limb deviations which occur particularly from the 5th month
on. The connection between the observed growth spurt around the 5th month of life and the
documented nutritional deficiencies of the foals is assumed as the cause.
Gothe, Christiane (1999):
Haptoglobin as an inflammation marker in the health control of thoroughbreds.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 94 pages.
Haptoglobin (hp) belongs to the group of acute-phase-proteins, that rapidly increase their
concentration in the blood during inflammation and tissue damage. This study was carried
out to explore if hp is a suitable marker in order to establish the health status of thoroughbred
race horses. Hp was investigated with the nephelometer-analyzer BN 100 (Behring
Diagnostics, Germany) using humanspecific antiserum. Blood samples were obtained from
61 thoroughbreds of one racing stable every four weeks for a period of 12 month (september
1995 - august 1996). In these samples the concentration of hp and additionally the content or
activity of enzymes, metabolits and minerals which are usually determined by the „Bonner
Informations- und Präventivsystem“ for horses, were examined. For evaluation 375 samples
could be used.
According to inflammatory reactions measured by the nephelometer-system, values below
55 mg/dl hp were considered as physiological.
Hp-concentration did not depend on time of day or sex. Mean hp-values decreased with
increasing age. During the year they followed a typical curve with higher values in autumn.
Significant changes could be observed in cases of acute inflammation and severe tissue
damage (respiratory diseases, open wounds). Hp-mirrows decreased in correspondence to
antibiotical treatment.
Horses suffering from inflammations of joints or tendons showed slight enhancement of hp-
concentration. Vaccination against viral respiratory diseases or rabies clearly caused
increase of hp-content in the blood.
Correlation coefficients between hp and the other blood parameters were low, although
higher hp-values could be recognized in samples with higher concentrations of AST, CK or
LDH.
It was shown that the determination of haptoglobin in the blood using the nephelometer-
system is a valuable instrument for the diagnosis of inflammatory diseases and therefore a
support in the routine health control of horses.
Gymnich, Stefanie (2001):
Haptoglobin as a screeningparameter in health management systems in the piglet
rearing.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 128 pages.
The aim of the present work was to examine to what extent and at which point in time the
parameter haptoglobin could be integrated into a chain oriented health management system.
Furthermore it was aimed at assessing the influence of different rearing systems regarding to
the practicability of including the parameter haptoglobin into the receiving inspection. Five
variants of the customer-supplier-contacts were tested including seven piglet breeding farms,
15 piglet rearing farms and two fattener farms.
The results of the preliminary study showed that stress determined by a three hour transport
caused no significant changes of haptoglobin concentration in blood of pigs in comparison to
the control group. This meant, for the main study, that transport or change of housing as
possible reasons for the increase of haptoglobin concentration in pigs' blood could be
excluded.
In the main study 1559 data from 43 test groups were available. It was found out that piglets
from one pedigree had significant lower haptoglobin concentrations at the moment of coming
into the rearing than animals coming from different pedigrees. A close connection between
the hygienic status of the rearing farm in the in-process inspection and the final inspection,
the daily weight gain of the later rearing as well as higher costs of medical treatment and the
haptoglobin serum concentration could be underlined.
The suggested test strategy combines the measurement of the acute-phase-protein
haptoglobin, check lists and a ranking system in the preventive health control. Favourable
points in time for the receiving inspection are three days before moving the animals to the
breeder or directly at the receiving time, for the in-process inspection three weeks after
receipt and for the final inspection three days before moving to the fattener.

Hackländer, Rainer (1997):
Investigations to feeding and growth of weanling warm-blooded foals during the
stable period.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 112 pages.
The aim of this investigation was to analyze the nutrition of weaned warm-blooded foals in
Westphalia during their first stable period and to compare these results with the
recommendations given by the Society for Nutrition-Physiology (1994). Kind and quantity of
feed fed to the foals were recorded on 35 farms on 5 times in intervalls of 5 - 6 weeks.
Samples of feedstuffs were analysed for nutrient content including Ca, P, Mg, Na, K, Fe, Cu,
Zn, Mn and rations for the foals were calculated. Furthermore several defined growth
parameters and the development of the limbs were recorded. Finally it was examined, wether
there was a relation-ship between growth, development and provision with energy and
nutrients.
Nutrition: The analysis of the ration calculations revealed great differences in the provision
with energy and nutrients of the weaned foals on the farms. An enormous excess was found
in the provision with energy, calcium, phosphorus, magnesium, potassium, iron and
manganese. Deficiencies were especially found in the provision with protein, sodium,
copper and zinc.
Growth: Between the months 5 and 17 the growth rates decreased strongly. The highest
growth rates were found up to the age of 10 months. The growth gains of the trunk lasted on
until the 2nd year of life. Growth periods characterized by increased gains were found for all
parameters in the months 5 to 7, for height at withers also between month 10 and 11.
Development of the limbs: Orthopedic developmental bone diseases were especially found in
form of enlargements of the fetlock joints, deviations of the limb formation and uncorrect
angles of fetlock joints and hoofs. These abnormalities were diagnosed for the most part
between the 5th and 10th month of life.
Relationship of nutrition, growth and development: A significant influence of different levels of
nutrition was prooved for the growth parameters body length and growth of knee to pastern,
as well as for the enlargements of the fetlock joints and for steep hoofs.
The results underline the importance of ration calculations, which are based on nutrient
analysis of the forage used in the farms. This is the basis to choose an adequate
supplement. It is advised to match the provision with energy and nutrients of the weanlings
with their different periods of growth in order to achieve a constant growth and to avoid
orthopedic developmental diseases.
Hartmann, Harriet (1999):
The importance of the dressage horses’ anatomy on its performance in theory and
practice.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 101 pages.
Aim of the study was to determine which anatomical aspects successful competition-riders
and authors of respected literature consider important for prospective dressage horses. An
attempt was made to quantify the level of knowledge among successful competition-riders
concerning the anatomy and biomechanical aspects of the horse.
Riders competing at Grand-Prix level or novice to advanced level were interviewed per
questionnaire. After evaluation a comparison between current knowledge and respected
equine literature was performed.
We found that when evaluating a horses’ aptitude for dressage, shape and positioning of the
neck is of eminent importance. An insufficient angulation of the horses’ hind limb is
considered negative on the animals dressage performance. Furthermore dressage lessons
take considerably longer to learn if the horse has short forelimbs and is narrow in the chest.
We could show that a horses’ aptitude for dressage is frequently judged by the quality of its
paces and not by its anatomical flawlessness. Often the one is not prerequisite for the other.
The interaction between anatomical characteristics and a horses’ movements are very
frequently not understood even among riders competing at an international level. Obviously
there is no direct correlation between the degree of theoretical knowledge and the riders’
level of competing.
The lack of theoretical knowledge is probably due to a practically oriented education among
young riders. Added to this, excellent horses resulting from stringent breeding criteria
nowadays make the necessity to cope with serious anatomical problems the exception and
not the rule. An affluent society prepared to pay considerable amounts for success also plays
a significant role. Although German dressage stands in high regard world wide, due to
continuous excellent performance, care has to be taken not to neglect theoretical education.
The interaction between the horses anatomy and gait should, so as to uphold the high
standard, be appreciated by riders of all classes.
Heintges, Ute (2003):
Investigations on the role of leptin in ruminants.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 150 pages.
The aim of the present study was to develop a valid method for the quantification of
circulating leptin concentrations in ruminants and to characterise the physiological relevance
of this hormone for those species. Using the double antibody technique, a competitive
enzyme immuno assay was developed and thoroughly validated. Based on this method and
on glucose infusion experiments (hyperglycaemic and euglycaemic/hyperinsulinaemic
clamps) in goats, the effects of both, active immunisation against leptin and treatment with
leptin injections on glucose and adipose tissue metabolism were investigated. In addition,
physiological changes of serum leptin concentrations during growth, pregnancy and lactation
were characterised in goats, sheep and cows. The regulation of leptin secretion was
investigated by testing the effects of injections with either prolactin, placental lactogen or
somatotropin on leptin serum concentrations in goats and cows, respectively.
Serum leptin concentrations were increased by active immunisation and also by injecting
leptin into goats but led to divergent alterations of insulin sensitivity: active immunisation
decreased insulin sensitivity, whereas leptin injections increased it in pregnant goats. Insulin
sensitivity was decreased in lactating goats when compared to pregnant animals. Leptin
injections led to decreased serum concentrations of non-esterified fatty acids (NEFA) in
pregnant goats. In contrast, lactating goats had higher basal NEFA concentrations and had
smaller fat cells than pregnant animals. Lactating animals did not respond to leptin injections
in terms of NEFA concentrations. Alterations of leptin serum concentrations inducible by
injections with prolactin or placental lactogen were limited to pregnant goats. Prolactin
transiently increased leptin serum concentrations within minutes, whereas placental lactogen
led to a decrease within hours after the injection. Application of somatotropin to cows
decreased plasma leptin concentrations in pregnant cows, but not in non-pregnant, lactating
cows.
Serum leptin concentrations showed comparable alterations during growth, pregnancy and
lactation as reported for humans and for rodents and therefore similar regulatory principles
may work for leptin in ruminants regardless of their metabolic particularities.
Hermann, Thomas (1998):
In vitro effect of 1α,25-dihydroxycholecalciferol and its analogs EB1089 and CB1093
on human endothelial cells and human breast cancer cells.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 108 pages.
1α,25-dihydroxycholecalciferol (calcitriol) affects the proliferation and differentiation of breast
cancer cells and has antiangiogenic activity. Thus, this steroid-like vitamin compound offers a
novel approach to the systemic treatment of breast cancer. Up to now the clinical use of
calcitriol was hampered by its calcium mobilizing effect. Recently, various vitamin D analogs
have been synthesized, which show by far a less mobilizing effect on calcium than calcitriol.
This project compared the in vitro antiproliferative and antiangiogenic effects of calcitriol and
of the two novel vitamin D analogs, EB1089 and CB1093, on human endothelial and human
breast cancer cells.
Calcitriol as well as both vitamin D analogs (EB1089, CB1093) inhibited the in vitro growth of
the human breast cancer cell lines T-47D and MDA-MB-468 in a time- and dose-dependent
manner. This antiproliferative effect was independent of the estrogen receptor-status of the
tumor cell lines. The proliferation of VEGF-stimulated human umbilical vein endothelial cells
(HUVECs) was also inhibited by calcitriol, EB1089 and CB1093. There were no cytolytic or
significant stimulatory effects of the tested compounds, neither with breast cancer nor
endothelial cells. In HUVECs, calcitriol also suppressed transiently the expression of the
VEGF-receptor KDR, but not of the VEGF-receptor flt-1. After a 5-day incubation of T-47D-
cells and MDA-MB-468-cells in a media containing 1 µM calcitriol, EB1089 or CB1093, the
concentration of VEGF in the cell-free media fell significantly. In contrast, the tested
compounds did not modulate VEGF gene expression. Since the relative concentration of
VEGF - in relation to a standardized number of 106 cells - showed no significant difference to
the control, it seems tenable to attribute the decrease of the concentration of VEGF primarily
to the antiproliferative effect of the tested compounds.
From these experiments’ data we can conclude that, due to their reduced calcium mobilizing
activity in vivo and their antiproliferative effect on estrogen-dependent and estrogen-
independent human breast cancer cell lines as well as on non-malignant human endothelial
cells, the vitamin D analogs EB1089 and CB1093 may provide a novel therapeutic tool for
the treatment of human breast cancer.
Kellersmann, Julia (2003):
The influence of O-GlcNAc on APP processing and Cdk5 activity.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 134 pages.
N-acetylglucosamine linked O-glycosidically (O-GlcNAc) to serin and threonine residues of
proteins is a poststranslational modification of proteins of the cytosol, the nucleus and of the
cytosolic domains of transmembrane proteins. It was shown, that the O-GlcNAc-modification
of proteins responds reciprocally to phosphorylation and therefore might have a similar
regulatory function as the phosphorylation itself. Extending these earlier studies, we were
able to show, that PMA treatment (activates PKC) and PUGNAc treatment (inhibits OGH) of
N2a- and HEK293-cells, which were transfected with wildtype APP695 (APPwt) or the
Swedish mutation of APP695 (APPsw), lead to altered APP processing. PMA treatment of
N2a-cells increased APPs-secretion in APPwt-transfected cells, while a decrease of Abeta
was observed in both transfectants and in APPwt-transfected HEK293-cells.
PUGNAc-treatment increased the Abeta-secretion in APPsw-transfected N2a-cells without
changing APPs-secretion. The increase in Abeta-secretion was also shown for APPwt-
transfected HEK293-cells. The modification of proteins with O-GlcNAc leads therefore to an
increased synthesis of amyloidogenic fragments.
We were also able to show, what Cdk5 is O-GlcNAc-modified. Because of the fact, that
phosphorylation of Ser 159 negatively regulates Cdk5, the O-GlcNAc-modification might also
have a regulatory function. Treatment of N2a-cells with PUGNAc and with the PKA-activator
dbcAMP paradoxically lead to an increase in the O-GlcNAc-level of several proteins which
was higher than in the presence of PUGNAc alone. The O-GlcNAc-modification might lead to
a dysfunction of Cdk5, which then results in increased O-GlcNAc-levels.
These observations provide evidence, that the O-GlcNAc-modification modulates APP
processing as well as the regulation of Cdk5.
Kissenbeck, Silke (1999):
Effects of conditioning on glycogen content and glycogen utilization in the gluteus
medius muscle of horses.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 111 pages.
Introduction. Muscle glycogen is an important substrate for energy production during
exercise. In humans it has been demonstrated that athletes with higher muscle glycogen
concentration are those with better endurance (BERGSTRÖM et al., 1976). Therefore an
increase of the glycogen concentration through conditioning may be interpreted as beneficial
for the endurance of an individual. The aim of the present study was to examine the effects
of conditioning horses according to their individual state of performance and to measure the
effects on glycogen content and utilization in the gluteus medius muscle.
Materials and Methods. The effects of 3 different conditioning programmes on muscle
glycogen concentration and utilization in horses were examined. Speed of exercise was
selected according to the blood lactate values for each horse derived from a standardized
exercise test (SET) before beginning a conditioning programme. Six 2-year-old Haflinger
stallions were randomly assigned to 1 of 3 conditioning programmes according to a 6x3 latin
square design: 45 min at their individual v1.5 or v2.5 and 25 min at v4. Each conditioning
programme lasted 6 weeks (21 exercise sessions), followed by 5 weeks without conditioning
(resting period). All exercise was carried out on a treadmill inclined at
17 %. Muscle biopsies were taken 5 times from the gluteus medius muscle at 2 cm and 6 cm
depth: before the start and in the middle of the conditioning period, at days 2, 9 and 35 after
the last exercise session.
Results. Glycogen concentration was not affected by conditioning until 9 days after finishing
conditioning at v1.5 and v2.5 for 45 min (p<0.05). By this time glycogen concentration in the
muscle samples taken at 6 cm depth increased by 47 % and 48 % respectively and remained
elevated until the end of the resting period. The amount of glycogen utilized per minute
during the SET was not influenced by conditioning or resting.
Conclusions. It was concluded that conditioning at lower intensity and for longer duration
seemed to increase glycogen stores in the muscle while faster intensity but shorter duration
exercise did not. To increase the likelihood of measuring effects of conditioning programmes
on muscle variables sampling should be done at different depths of a muscle and at several
days after finishing a conditioning programme.
Kosiedowski, Petra (2000):
Studies in alterations of faeces consistency in suckling foals during the foal-heat of
their mothers and after application of two homoeopathic drugs.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 104 pages.
Nearly all suckling foals suffer during the so-called foal-heat (that means the first heat post
partum) of the mares under a usually temporary diarrhoea. Aim of this study was to register
the continuous alteration of faeces during this period on the basis of defined parameters and
to judge precisely the effect of a preventive application of the homoeopathic combinations
Nux vomica-Homaccord and Veratrum-Homaccord under standardised conditions.
59 suckling foals from different breeds (Thoroughbred, Trotter, Warmblood) were split up into
two groups by random selection. The above mentioned preparations were applied orally with
blinding in combined form (5 ml of each) on the 8th, 9th, 10th and 11th day post partum,
respectively a Placebo was given. To investigate the alterations of faeces and the effect of
the preparations, faecal samples were collected from the rectum on the 7th, 9th, 10th and 12th
day post partum. The examination of faeces consisted of pH, water content, total aerobic and
coliform counts.
During the research period following results could be obtained:
The faecal pH increased from 7.3 to 8.0. There was no statistically significant influence of the
drugs on faecal pH.
The mean water content increased between the 7th and 12th day post partum from 69% to
82% in the placebo-group and to 74% in the experimental group. A positive influence of the
two homoeopathic combination drugs on the water content could be statistically assured
already from the day after the first application of the homoeopathic combination drugs. This
influence increased with continued application.
The total aerobic count increased from 8.8x1012 to 2.6x1013/g faeces in the placebo-group. In
the homoeopathic treated group the total aerobic count decreased in general. This positive
different development could be statistically assured.
In the placebo-group the mean coliform count increased from 5.9x107 to 1.3x108/g faeces. In
the experimental group only minor changes in coliform counts could be observed compared
with the starting level. The different course of coliform counts development between both
groups could be statistically assured already on the first day after treatment.
Therefore in respect to the main criteria of the diarrhoea as water content, total aerobic count
and coliform count a positive effect of the preventive application of the homeopathic
preparation Nux vomica-Homaccord and Veratrum-Homaccord on the"foal-heat-
diarrhoea" was statistically assured.
Kosswig, Ninetta (2003):
Dissecting Class A Scavenger Receptor Mediated Cell Adhesion and Lipoprotein
Internalization.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 110 pages.
Macrophage class A scavenger receptors (SR-A) are trimeric transmembrane glycoproteins
that can bind a variety of ligands including modified lipoproteins and bacterial products.
Through its ability to internalize these ligands, SR-A is thought to be involved in many
physiological and pathophysiological processes such as host defense and atherosclerosis.
In vitro, SR-A also mediates cell adhesion to modified extracellular matrix proteins. However,
the physiological role of SR-A mediated cell adhesion is unknown. The goal of this project
was to dissect SR-A mediated cell adhesion and ligand internalization through structure-
function studies and to develop a mutant of SR-A that specifically lacks the adhesive
properties. It appeared that SR-A mediated adhesion and ligand internalization depend on
the same extracellular domain. Therefore, I investigated the role of cytoplasmic domains for
SR-A mediated adhesion. Different cytoplasmic mutated SR-A constructs were stably
expressed in human embryonic kidney (HEK-293) cells. I found that a mutated SR-A
deficient in all but the six amino acids proximal to the membrane of the cytoplasmic tail (SR-
A∆1-49) was able to mediate cell adhesion, but not receptor internalization. Substitution of the
SR-A cytoplasmic tail with that of the transferrin receptor resulted in retention of this chimeric
receptor in the endoplasmic reticulum demonstrating that the SR-A membrane proximal
amino acids are also critical for transport of the receptor from the endoplasmic reticulum to the Golgi apparatus. In summary, my results demonstrate that SR-A-mediated adhesion and internalization require distinct cytoplasmic domains and I developed a mutant SR-A (SR-A∆1- 49) that specifically meditates cell adhesion. This mutant will make it possible to specifically
address the physiological role of SR-A mediated adhesion.
Kreft, Dagmar (1997):
Development of an in vitro-model for studying the influence of gliadin on the
hydrolases of the duodenal brush border membrane in coeliac disease in remission.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 103 pages.
Background: Coeliac disease is characterized by a permanent intestinal intolerance to
dietary wheat gliadin and related proteins. Gliadin causes intestinal villus atrophy in afflicted
subjects and patients on a gluten free diet recover completely. The molecular mechanism
inducing the mucosal damage in coeliac disease is still unknown. The purpose of this study
was to evaluate a possible correlation between the mucosal damage caused by gliadin and
the biosynthesis of the intestinal hydrolases. Using the organ culture of intestinal biopsies, an
in vitro-system for coeliac disease in remission was developed to verify the hypothesis of an
impaired biosynthesis. Besides the enzyme activity of intestinal disaccharidases was
measured to prove whether this level is also influenced.
Patients, Material, Methods: Peroral biopsies taken by suction biopsy capsule or endoscopy
of the duodenum from 14 coeliac patients in remission (following a gluten free diet for at least
2 years) and 29 healthy children were organ cultured for 24 hours in presence or absence of
gliadin peptides. A peptic-tryptic digest of maize prolamine served as the non-toxic control.
The effect of the additives on the biosynthesis of several hydrolases (Lactase-Phlorizin-
Hydrolase, Sucrase-Isomaltase, Maltase-Glucoamylase, Aminopeptidase N, Dipeptidyl-
peptidase IV, Angiotensin I-converting enzyme) was studied by metabolic labelling of the
protein biosynthesis (using [35S]-methionine), followed by immunoprecipitation and SDS-
PAGE. Finally the effects were visualized by autoradiography and quantified by densitometric
scanning. The influence on the enzyme activity of the disaccharidases lactase, sucrase,
isomaltase and maltase was determined by a modificated method of Dahlqvist.
Results: A rapid and specific gliadin-induced reduction of the biosynthesis of intestinal
hydrolases was demonstrated in biopsies from coeliac patients on a gluten free diet. This
phenomenon was statistically significant for all studied disaccharidases and peptidases (
###>0.01), whereas it was neither seen after incubation with maize prolamine nor in healthy
children. On enzyme activity level no effect of gliadin after 24 hours of incubation could be
shown. Because of beginning necrosis in the biopsies a longer incubation was not possible,
so potential later effects could not be examined.
Conclusions: The established model is suitable for studying the in vitro-situation of coeliac
disease in remission. Moreover, the results indicate a fast effect of gliadin peptides on
inhibiting the biosynthesis of hydrolases of duodenal brush border membranes. However,
Gliadin does not seem to influence the post-translational processing of the hydrolases,
because both the precursor and the mature forms of the proteins are reduced. It remains
unclear whether gliadin primarily influences the protein biosynthesis or whether this is due to
a secondary effect of an impaired mRNA synthesis. The early modifications within 24 hours
of incubation suggest an immediate effect of gliadin peptides on the enterocytes, possibly via
cytokines.
Kreyenschmidt, Judith (2003):
Modeling of the quality change of fresh meat and color-change of time-temperature-
integrators for monitoring food freshness.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 167 pages.
The main purpose has been the investigation of two systems of Time-Temperature-
Integrators (Prototype Bayreuth/Haifa and M2/M3 of Co. Lifelines) to control the quality of
fresh poultry and pork during the chill chain. Another goal has been the verification of two
different models describing the kinetics of spoilage and the kinetics of color-change. One
model bases on the scientific Arrhenius-Model and the other model takes advantage of
sophisticated mathematical descriptions of the data to create temperature-time-functions.
While the food and the TTIs (Time-Temperature-Integrator) have been exposed to different
temperatures, its dependency of time and temperature has been investigated with the use of
extensive experimental setups: 137 time-runs of spoilage-measurements have been taken
and about 300 time-runs to measure the color-change of different Integrators. Each run
consisted out of approx. 10 single measurements, so that more than 4000 single data got
acquired and analyzed.
The results showed that sensory numbers and microbiological parameters are useful to
describe food spoilage and the color-change of the Time-Temperature-Integrators. Each
model is able to characterize the kinetics of spoilage of food and color-change of integrators
and they underline the good capability of the TTI Bayreuth/Haifa to control and check the
quality of meat during the chill chain. One major attribute of this Integrator is its adjustability
of its behavior in color-change. Therefore the duration of UV-radiation to charge the
integrator may be changed or different derivates can be used.
Lehnert, Susanne (1998):
Implementation of quality management systems in farms exemplary in meat
production.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 174 pages.
The objective of the work at hand was to exemplarily implement and document quality
management systems which are at the first time developed for the structures of german
agriculture. The working goups of the pilot project were composed of members of pig
fattening farms, production groups of pig fatteners, service organizations and science. An
additional task was to prepare some pig fattening farms for the certification according to the
DIN EN ISO 9000ff. standards.
The analysis of existing literature shows that animal keeping farms were more and more
forced to structure and expose their measures of consumer protection and assurance of
origin due to legal restrictions and quality management activities of the meat processing
branch. Chain-encompassing concepts of quality assurance focussing on process control are
at present theoretically planned, but not yet realized in practise. The proposal developed in
the pilot project, how to implement and certify standard oriented quality management
systems in pig keeping farms, shall contribute to a faciliated interpretation of the standard for
pig production and to an enhanced and broadened implementation. The proposal contains
six successive steps:
Definition of objectives
Project planning and preparation
Analysis of deficiencies
Development and application of action plans
Internal auditing
External auditing
This so called core modell may generally be used, disregarding the initial basis. The modell
distinguishes four possible variants of initial basis: single farm, groups of farms, production
community in definite structures and production community with quality standards in vertical
integration. Depending on the variant, additional elements will be added to the core modell.
As a result of the empirical study, the work supplies structure plans and guidelines as well as
solution examples which especially refer to health management measures.
Lohmöller, Ludger (1997):
Studies for the prevention of postpartal cylce- and reproductive disorders in high
yielding dairy cattle with the usage of the homeopathic drugs Traumeel, Ovarium
compositum and Hormeel, analysed with progesterone profiles.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 97 pages.
Introduction: In the present study the postpartal reproductive period of dairy cattle should
controlled and it should prooved, if the use of the homeopathic drugs Traumeel, Ovarium
compositum and Hormeel promote an earlier restart of the cyclic ovarian activity post
partum and reduce the disorders of cycle and reproduction.
Material and Methods: 127 milk cows with the average of 8.941 kg FCM were devided
accidentally into three groups. The first injection given postpartum to group 1 was the drug
Traumeel, the two injections thereafter consisted of the drug Ovarium compositum. The
group 2 started with Traumeel, too, the following two injections consisted of the drug
Hormeel. In the group 3, the control group, the cows were given „water for injections“ as
placebo. To provide complete and detailed information about normal cyclicity or disorders in
reproduction of the cows, progesterone profiles were worked out individually.
Complementary, data of milk yield, insemination and parturition were integrated into the
evaluation.
Results: Analysis of the milk-progesteron profiles: In the groups treated with homeopathic
drugs the ovarian activity started earlier than in the control group. The differences were not
significant. Also no significant differences were found in other criteria of the cycle between
the three groups.
Analysis of reproductive disorders: This study shows, that the limiting value of 28 days p.p.
for a female convalescence, suggested in earlier studies, is not physiolocical. 2/3 of the cows
in the control group were still acyclic at this time. 49 days p.p. ca. 20 % of the cows stayed
acyclic, which is considered to be an acceptable rate. Therefore, the convalescence period
for high yielding dairy cattle should be extended for more than two weeks. In the groups
treated with the homeopathic drugs there was considerably more cyclic cows. No significant
differences were found among the further reproductive disorders looked at this study.
Analysis of the reproductive parameters: In group 1 and 2 the first heat was occurred by the
farmer about 10 days earlier than it did in the control group. These difference was not
significant. The other reproductive parameters and the rates of loss and the reasons for that
show slight advantages in the groups treated with homeopathic drugs, but these differences
were not significant.
Lüpschen, Christoph (1997):
Aussagekraft des Body- Condition- Score Testes im Hinblick auf das Partus-
Syndroms.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 85 pages.
The present doctoral thesis aimed at finding out whether the Body- Condition- Score test is
an appropriate means for the management of health care precautionary measures on a dairy
farm. With the aid of the BCS- test the nutritional state of the cows was determined on the
basis of visible and palpable findings.
This question was to be answered with the help of economic efficiency parameters which
were to be determined in a field project.
For this purpose the disease dates, productivity dates, fertility dates and leaving dates of 248
cows from the „Bergisches Land“ were registered over a one- year period.
On the 280 th. day of their pregnancies the body- conditions of these cows were determined
with the help of the Body- Condition- Score test. After the test the cows were subdivided into
three different groups. The cows which were „slim“ at the beginning of the test formed group
1 with the indexes of 1.5 and 2. Cows with standard weights formed group 2 ( BCS- indexes
of 2.5, 3. and 3.5). The „fat“ cows with indexes of 4, 4.5 and 5 finally formed group 3.
Cows from group 3 revealed a higher disease rate, less productivity, a lower fertility rate and
a higher leaving rate compared with the other cows.
Cows from group 1 achieved less productivity and a higher leaving rate compared with cows
from group 2.
With regard to economic efficiency cows from group 2 showed significantly better results
than cows from groups 1 and 3.
Based on results from literature as well as those established in this doctoral thesis the Body-
Condition- Score test can be recommended to dairy farmers. This test is an appropriate
means to optimalise cow feeding within the management of health care precautionary
measures.
Marx, S. (1999):
Lactate concentration in blood, saliva and sweat of horses during exercise with
special emphasis on the Salivette® as a sample collecting device.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 96 pages.
The aimes of the present study were to evaluate the Salivette® as a practical, easy to handle
and inexpensive device for the collection of saliva and sweat of horses during exercise and
to find out if lactate is present in the saliva and/or sweat of horses.
Materials and Methods. 6 Haflingers and 5 Standardbred trotters were used in this study. All exercise workouts were done on an low speed treadmill with a 17 % incline. The Haflingers were exercised at three different programmes at a constant speed: „25 min“ (3.8 +/- 0.24 m/s), „45 min slow“ (3.1 +/- 0.24 m/s) and „45 min fast“ (3.5 +/- 0.28 m/s). In addition horses had to perform a standardized exercise tests (SET) consisting of several steps of 5 min duration each with one minute of rest between 2 steps. The Standardbreds performed one exercise of 30 min duration at a constant speed ranging from 3.2 to 4.0 m/s. Sweat was collected from the pectoral skin, saliva at the height of the 3rd premolar and under the tongue. The sampling time was always 30 sec. Each substrate was taken during the breaks of the SET and immediately after finishing the continuous exercise. In order to compare lactate concentrations saliva and blood or sweat and blood, resp. these samples were taken simultaneously. During SET blood samples were drawn from the jugular vein and after continuous exercise from the pectoral skin via stab incision. Volumes of sweat and saliva were quantified by extracting fluids from vials with a pipette, lactate analysis was performed enzymaticaly. Results: The sweat and saliva volumes obtained were not affected by the duration of the SET or the type of exercise programme but were always sufficient for analysis purposes. Sweat and saliva of horses contained lactate. During SET there was a negative correlation between the lactate concentration in blood and sweat, but not between blood and saliva. No correlation was found between lactate concentrations in the substrates at the end of the continuous exercise. With increasing duration of the exercise blood lactate increased in the Standardbreds, while sweat lactate concentration remained constant. Conclusions. The Salivette® can be regarded as a practical device for collecting sufficiant amounts of sweat and saliva for the purpose of analyses. It can be also applied
during exercise, because its handling is non invasiv, simple and fast. Performance diagnosis
using sweat or saliva lactate concentration and a subsequent renunciation of blood sampling
is not possible at this time.
Mäß, Carmen (2002):
Investigations into the role of the O-glycosidically linked N-acetylglucosamine
modification of proteins in the processing of the human amyloid precursor protein.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 127 pages.
The Amyloid precursor protein (APP) plays a central role in the pathogenesis of Alzheimer’s
disease (AD). APP is cleaved by so-called α-, β- and γ-secretase leading to the generation of
several proteolytic fragments. This processing of APP is regulated by a variety of different
signaling pathways.
N-acetylglucosamine O-glycosidically linked to serine or threonine residues (O-GlcNAc) is a
ubiquitous intracellular carbohydrate modification of proteins. O-GlcNAc may be involved in
the multimerization of proteins and may function as an alternative signal transduction
pathway to phosphorylation.
Based on former investigations demonstrating that (a) APP is O-GlcNAc-modified and (b) in
human brain areas of AD patients the O-GlcNAc expression of proteins is significantly
upregulated, the aim of the present study was to elucidate the role of the O-GlcNAc
modification of proteins for the proteolytic processing of human APP695. Experiments were
performed on N2a cells stably transfected with the cDNA of human APP695. Human APP695
expressing N2a cells exhibited longer neurites and an increased cell adhesion compared to
non-transfected, parental N2a cells. These observations are in agreement with former
investigations on other APP-expressing cell types.
It was shown that human APP695 expressed by N2a cells is O-GlcNAc-modified. The
immature protein was more heavily O-GlcNAcylated than the mature form. This observation
was shown to be true for the wild type as well as the Swedish mutant of human APP695.
Increased O-GlcNAc-levels of proteins did not have any significant influence on the secretion
of human APPs and APPs respectively. On the contrary, it resulted in a significant reduction
of the secreted human A x-40; this, however, needs to be confirmed in additional
experiments. This preliminary result may hint at the involvement of O-GlcNAcylation in the
regulation of the proteolytic processing of APP.
Furthermore, it was shown that the increased O-GlcNAc-levels of proteins lead to an
enhanced expression of the human APP695 in neurites. As a result, O-GlcNAcylation of APP
itself or of other proteins may play a major role for the axonal transport of APP.
Pfuhl, Ralf (2000):
Determination of meat ripening processes and meat quality criterions of pig meat by
recording the content of free amino acids with High Performance Liquid
Chromatography (HPLC).
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 122 pages.
The ripening of Meat is a process of high complexicity including the development of taste and
structure of the muscle fibres of a slaughtered animal. The development of the meat quality
post mortem can be described objectively by the meat quality parameters pH-value, meat
colour and the electric conductivity. After the animal is slaughtered, the muscle proteins are
modified and degraded by proteolytic processes, which release peptides and free amino
acids in the surrounding muscle tissue.
In this Work the development of the content of free amino acids in samples of the musculus
longissimus dorsi of ripening pork at 45 minutes, 24, 48 and 72 hours post mortem were
investigated to make an objective statement on the post mortem age and the quality status of
pork beside the known quality parameters.
To achieve this, the free amino acids of the m. longissimus dorsi of 98 crossbred pigs of
defined origin were stored at 4oC and analysed at the times mentioned above post mortem.
For the analysis of free amino acids, an amino acid analyser, based on the high performance
liqid chromatography (HPLC) was used. Contemporary, the meat quality parameters of the
meat samples were determined.
The analytical system used in this work is suitable to detect free amino acids in ripening pork.
41 substances can be determined in one detection step. Eight of this 41 substances showed
a continuous increase in their content during storing the meat samples (threonine, serine,
methionine, isoleucine, leucine, tyrosine and phenylalanine). The content of the amino acid
taurin decreased continously in the duration of ripening pork.
To each of the investigation times post mortem a defined content of the eight substances
(threonine, serine, methionine, isoleucine, leucine, tyrosine, phenylalanine, taurine) can be
associated. All meat samples, which tended to produce PSE-Pork, showed higher Alanin
levels as normal ripened pork. Carnosin as a dipeptide appeared in high amounts to all times
and in all samples. It should be worth to have a closer look on Carnosin in the future. No
correlations could be found between the the amount of free amino acids and the measured
meat quality parameters in the m. longissimus dorsi of the investigated pig meat samples.
Despite of the fact, that no correlations between free amino acids and meat ripening
parameters could be found, it is possible to describe different meat aging stages in pigs m.
longissimus dorsi by their amino acid profile of the eight substances mentioned.
Quade, Reinhild (2004):
Importance of NCAM-mediated Signaltransduction for Endocytosis and Neurite
outgrowth.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 109 pages.
The neural cell adhesion molecule NCAM is a membrane-associated glycoprotein expressed
on the surface of neural cells. NCAM plays a pivotal role in neuronal development and rege-
neration and is involved in synaptic plasticity associated with learning and memory in the
adult.
NCAM is a member of the immunoglobuline superfamily and exists in three major isoforms.
NCAM180 and NCAM140 are transmembrane proteins with cytoplasmic tails of different
length, NCAM120 is bound to the plasma membrane via a glycosylphosphatidylinositol an-
chor. All three isoforms have an extracellular domain consisting of five Ig-like domains and
two fibronectin type-III domains (Cunningham et al., 1987).
Since the PEST sequence of aplysia apCAM – a homologue of NCAM – plays a key role in
endocytosis of apCAM (Bailey et al., 1997), we investigated whether the PEST sequence of
human NCAM140 is also important for its internalization, which may trigger signal transduc-
tion mechanisms implicated in neurite outgrowth in a similar way as has been shown for the
neural cell adhesion molecule L1 (Schmid et al., 2000).
The presented results indicate an influence of the PEST sequence of human NCAM140 on
its internalization and on neurite outgrowth in rat B35 neuroblastoma cells.
Riesen, Guido (1999):
Relationships between the rennet coagulation properties of milk and selected
biochemical parameters.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 136 pages.
The coagulation properties of raw milk play an important role within cheese processing.
Direct measurement of the renneting properties requires special equipment and time. Target
of this study was therefore to evaluate the relationship between the coagulation properties of
milk and some biochemical milk parameters which are used within dairy herd programs as
screening parameters to control the feeding regime [acetone and milk urea content ], udder
health [pH-value, lactate dehydrogenase activity (LDH)] and milk quality [true protein and
casein protein content, protein genotype]. 119 dairy cows were investigated on 3 farms in
Brandenburg, Germany. Quarter foremilk samples were taken from each udder quarter at 3
times, starting with the first sampling at day 21 post partum and every next 14 days. For final
calculation 1335 samples were evaluated. To determine the coagulation properties the
viscosity of the collected milk samples was measured. For this purpose an 8 channel
computer based prototype (named CLOTTER) was constructed. For the core evaluation the
milk samples were divided into 4 quality grades (G1, G2, G3, G4) according to an index
based on rennet clotting time (RCT) and curd firmness. Quality grade 1 (G1) represented the
best coagulation properties, quality grade 4 (G4) the poorest. The LDH, the pH-value and the
casein protein content were significantly declining from G1 to G4. The urea and true protein
content were different between G1, G2 and G3 but not between G1 and G4. Highest values
for urea and true protein were measured in G1 and G4. The average aceton value in the milk
did not differ between the groups. However 4, 9, and 16 % of the samples in G1, G2 and G3
had aceton levels > 100 µmol/l. Within the different combination of ∃-, 6-Casein and ∃-
Lactoglobuline genotype the pairs with at least one B allel of the named protein genotype
were superior to the others. Especially 6-Casein BB pairs showed excellent renneting
properties. Within a discrimination model the prediction of the coagulation properties of a milk
sample was possible at 58,5 % if pH-value and true protein content respective 63,8 % if all
screening parameters were included into the calculation. However the classification with the
evaluated screening parameters was good for the premium and critical grades (G1, G4 > 75
%; G3: 70 %) but less successful for the average(G2: 51 %). It can be concluded that a
suitable milk for premium cheese production must fulfil at least following requirements: pH-
value < 6,70; true protein content > 3,00 %, casein number > 80 %, LDH < 85 U/l. The
“cheese yield performance“ of a herd should be controlled via a monitoring of the milk urea
and aceton content in the milk and by knowing the protein genotype character of each cow.
Schöneseiffen, Nicole (2000):
A study of the losses in training time incurred by riding horses as a result of illness
and the evaluation of training stress and training strain in dressage sport horses.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 115 pages.
The purpose of the present study was to obtain epidemiological data on diseases in riding
horses which have both participated and not participated in competitions, as well as to
observe dressage training and evaluate training stress in horses successfully competing in
dressage events. The period of observation was from November 1992 to July 1993.
103 horses from five stables were grouped according to their use and the type of observation
as follows: 19 successful dressage sport horses which were intensively observed, 27
dressage sport horses which were competing but not intensively observed, 27 dressage
horses which were being trained for dressage but not yet competing and 34 riding horses
ridden for pleasure. For the description of type, duration and content of daily training exercise
7 successful L- and 10 S-dressage sport horses were selected. Training stress was
evaluated using blood lactate concentration and heart rate levels. Data on diseases was
collected by questionnaire and supported by information supplied by the veterinarians.
54.3 % of the 103 horses fell ill at least once during the observation period. 109 cases of
illness occurred. Disease frequency differed significantly according to the use of the horses.
The intensively observed dressage sport horses fell ill more often than the other types of use.
In this group there was also a higher incidence of horses falling ill more than once (63 % of
the total) whereas the percentages of the other groups falling ill more than once ranged only
from 9 to 22 %. The frequency of the types of diseases also differed significantly. Most of the
illnesses (57 %) affected the limbs and also caused the longest time out of training with a
mean of 24 days (+ 27 days). This category was followed by respiratory diseases (18 %), the
group of "other diseases" (18 %), and the gastrointestinal diseases (7 %). Although the
intensively observed horses had a higher incidence of damage to the locomotor system (71
%) compared to the other types of use (43 % to 52 %), the rehabilitation period of 15 days
was shorter.
With a maximum lactate concentration of 2.2 mmol/l after standardised dressage exercises
and a maximum heart rate of 133 beats/min the training stress for the intensively observed
dressage sport horses was low compared with jumping, cross-country and race horses.
There were no differences between the dressage exercises. All data indicated a purely
aerobic energy metabolism. In spite of this, the training of the S-horses seemed to be more
intensive than that of the L-horses. This is indicated by the incidence of "dressage training
with a rider" which, at 62 %, was higher for the S-horses than for the L-horses (44 %), while
the L-horses had a higher incidence of "lungeing" and "free movement" without a rider. In
addition, the training session for the S-horses contained more dressage exercises per
session (= 25.6) than that for the L-horses (= 14.4). The difference was significant. The walk
dominated in the training session for the L-horses, taking up almost half of the total time,
whereas the training time for the S-horses was shared almost equally between the walk, the
trot and the gallop. The mean heart rate of the L-horses at training differed with 99 beats/min
(+ 11 beats/min) significant from the S-horses with 109 beats/min (+ 12 beats/min) of the S-
horses, although the L-horses were trained for a longer time (around 48 minutes per training
session) than the S-horses (40 minutes per training session). In contrast to this, the S-horses
had 7 % more rest days over the research period than the L-horses. An irregular training
programme causes health problems, however, as the uneven training stress can lead to
premature wear on the tendons, ligaments and joints.
Sommersberg, Britta (2000):
Interzelluläre Kommunikation im Ovar: Der Einfluß von FSH auf die funktionelle
Kopplung durch Gap junctions sowie die Phosphorylierung und Expression von
Connexin 43.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 92 pages.
In the ovarian follicle, granulosa cel s (GC) are functionally coupled by gap junctions (GJ),
which mainly consist of the GJ protein connexin 43 (Cx 43). GJ are intercellular channels,
which enable adjacent cells to exchange ions and molecules of a molecular range less than
1,000 Da. While studies in Cx 43 Knock Out (KO) mice indicate the indispensable role of Cx
43 in follicular development, little is known about the regulation of this protein in GC.
However, we and others found that Cx 43 protein and mRNA levels are higher in large
follicles than in small follicles. Since follicular development is tightly regulated by Follicle
Stimulating Hormone (FSH), we hypothesized that FSH could also be involved in the
regulation of Cx 43. Because multiple factors present in a follicle do not allow to dissect out
the action of FSH we addressed this question by using a rat granulosa cell line (GFSHR-17),
which expresses the FSH-receptor and forms GJ. In this cell line, FSH acutely improved
functional coupling as observed by a modified single-cell whole-cell patch clamp technique.
This increase in GJ communication was associated by a decrease in phosphorylation of Cx
43 observed within 10 minutes after addition of FSH. Furthermore, Cx 43 mRNA levels were
elevated 6 - 9 h after addition of FSH to the cells. This increase in Cx 43 mRNA was
paralleled by reduced proliferation state and increased steroid synthesis in GFSHR-17.
Additionally, Cx 43 protein levels increased 24 h after addition of FSH. In particular, the
polyphosphorylated form of Cx 43 increased, whereas the less phosphorylated form
decreased. In summary and conclusion, FSH acutely improves GJ communication through
existing GJ. This regulation involves dephosphorylation of Cx 43. In long term, FSH
increases Cx 43 gene and protein expression. The higher phosphorylation state of Cx 43
observed in this time period may implicate the more stable form of Cx 43. Thus, FSH is a
direct regulator of GJ communication and Cx 43 protein phosphorylation as well as Cx 43
gene expression. The observed changes in GFSHR-17 cells indicate that FSH acts to
regulate the cell to cell communication via GJ in differentiating follicular GC.
Stelz, Hansjochen (1998):
Investigations on the aerobic and anaerobic biological fixed film filtration in a marine
recirculating aquaculture system.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 133 pages.

The suitability of a closed recirculating aquaculture system using saltwater was investigated.
This study focussed on:
Acceleration of the start-up period of the biofilter
Use of the controlled denitrification
Investigation on the biofilter performance and factors influencing the biofiltration.
The trials were run in three closed recirculation systems. Saltwater was prepared by adding
sea-salt to tap water. Rainbow trout (Oncorhynchus mykiss) served as reference animals in
trials where the systems were stocked. Stocking densities ranged from 6.22 to 58.6 kg/m3
rearing unit. Three diets with different crude protein concentrations (44.2; 48.3 and 53.3 % in
dry matter) were used.
The shortest start-up period (5 days) to adapt biological filtration (nitrification and
denitrification) from freshwater to seawater was achieved by increasing the salinity in a single
step. NO3-contents and pH-values were stabilized by controlled denitrification.
NH4-excretion of fish rose depending on the dietary crude protein concentration and was 35;
39 and 54 g N per kg dry diet. The demand on methanol, which was used as organic carbon
source for denitrification, was depending on the oxygen-input into the denitrification-unit and
the feed composition.
The maximum performance of the denitrification-unit could not be detected. The ammonia
removal rate was inhibited by lower pH-values and higher concentrations of suspended
solids in the rearing water. The maximum removal rate was 0.20 g N *m-2 *d-1 (water
temperature 14.4°C).
Strompen, Oliver (2001):
Studies related to the endogenous steroid profiles in horse urines using gas
chromatography/mass spec-trometry.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 285 pages.
Destination: The purpose of the present study was to develop and validate a specific analysis
procedure for the determination of qualitative and quantitative endogenous steroid profiles in
horse urines using gas chromatography/mass spectrometry (GC/MS). Profiles of steroid
hormones (estrogens, androgens, progestagens and corticosteroids), their precursors and
their metabolites were monitored.
Methods: The pattern of urinary excretion of steroids was determined by gas
chromatography/mass spectrometry (GC/MS) in 322 thoroughbred horses (106 colts, 113
mares, 103 geldings). The method included deuterated internal standards, e.g. [2,2,4,4-2H4]-
etiocholanolone, solid-phase extraction, derivatisation (trimethylsilylation) and GC/MS.
Results: Full-scan screening identified 2 androstenes, 11 androstanes, 3 estratrienes, 3
estranes, 1 estrene, 5 5-pregnenes, 5 4-pregnenes and 10 pregnanes.
The analysis procedure was categorized as standard- or reference procedure on the basis of
characteristic properties, e.g. detection limits, selectivity and uncertainty. The procedure was
validated at three calibration ranges. The selected ion mode was used for quantitation from
calibration curves, which exhibited a linear response (r > 0.98). The lower quantification limits
of the steroids ranged between 0.5 and 2 ng/ml (the detection limits about 2-fold lower). The
assay recoveries of steroids were reproducibly high. The intra- and inter-assay coefficients of
variation were < 10 %. Urinary univariate reference ranges of selected endogenous steroids
were measured using samples collected during regular “doping” control.
The urinary steroid excretion pattern, measured by GC/MS, is a noninvasive, high specific
and nonselective method in the differential diagnosis of abnormal steroid matabolism.
Zelczak, Georg (1998):
Longchain-polyunsaturated fatty acids in the nutrition of newborns and infants.
Institute of Physiology, Biochemistry and Animal Hygiene, Faculty of Agriculture, University
of Bonn, 88 pages.
Background: Recent clinical studies have shown the importance of dietary long chain poly-
unsaturated fatty acid (LC-PUFA) supplementation especially docosahexaenoic acid (DHA)
and arachidonic acid (AA) in preterm infants for visual acuity and psychomotor development.
It is less clear if term infants would also benefit from LC-PUFA supplementation to infant
formula. The aim of the present study was to evaluate, wether LC-PUFA supplementation of
infant formula results in a comparable LC-PUFA status of blood and a comparable
development of psychomotor and visual functions like breast-fed infants.
Patients, Material, Methods: A total of 123 healthy term infants were included in the
prospectiv, randomized double-blind-study. They received human milk (HM; n=65) as a
control group or were randomized to a conventional formula (FM-; n=25) or LC-PUFA
enriched formula (FM+; n=33; docosahexaenoic acid, DHA: 0,54% of total lipids; arachidonic
acid, AA: 0,11% of total lipids) for the first 4 months of life. Venous blood was taken at birth
from the umbilical cord and at the age of 2, 4 and 12 months. Lipids were extracted from
erythrocytes and plasma with chloroform/methanol. Lipidclasses such as phospholipids,
triglycerides and sterol esters were seperated by thin-layer chromatography and fatty acid
methylesters were analysed by high-resolution capillary gas-liquid chromatography.
Psychomotor development, body weight, height, head circumferences and skin fold
measurements were evaluated at the age of 2, 4, 9, 12 and 18 months. At 9 months visual
acuity was measured by preferential looking procedure.
Results: Altogether the fatty acid distribution in the lipidclasses of the study groups reflected
the dietary intake of LC-PUFA. Significantly higher amounts of DHA were found in the blood
of the infants receiving FM+ in comparison to HM fed infants at the age of 2 and 4 months. In
contrast the FM- group showed lower values. Both formula groups had significant lower
amounts of AA in the plasma lipidclasses at the age of 2 and 4 months. Remarkably high
values of docosatetraenoic acid (DTA) and docosapentaenoic acid (DPA) could be found in
the phospholipidclasses of FM- fed infants at the age of 2, 4 and 12 months.
Psychomotor development, body weight, height, head circumferences and skin fold
measurements were not significantly different among the dietary groups at 2, 4, 9, 12 and 18
months. Just so no differences were found in the visual functions at the age of 9 months.
Remarkably there was an accumulation of drop outs because of gastrointestinal symptoms in
the FM+ group.
Conclusions: LC-PUFA enrichment of formula for term infants effectively enhances
erythrocyte and plasma LC-PUFA amounts. However, a better adaptation of LC-PUFA content of the used formula to the contents of human milk is desirable, since DHA levels were too high and AA levels too low in the FM+ group. Infants feeding with conventional formulas had inadequate LC-PUFA levels. Therefore, a supplementation of infant formula seems to be necessary to reach comparable amounts of LC-PUFA in the blood of term infants. On the other hand, no differences were found in the psychomotor and visual development among the dietary groups. For a better evaluation of the visual and cognitive development long-term follow-ups should be done. Beyond it is necessary to investigate, wether there is a correlation between the occurance of gastrointestinal problems and the supplementation of LC-PUFA.

Source: http://www.lwf.uni-bonn.de/forschung/diss-2006/en/physiologie_e.pdf