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C Aurich

Publications and source records attributed to C Aurich.

At least 19 recordsLinked to original sources

Influence of bacteria and gentamicin on cooled-stored stallion spermatozoa.

This study investigated effects of bacteria from the genital tract of horses and the effect of gentamicin in semen extender on spermatozoal function in cooled-stored stallion semen. Semen was collected from healthy stallions and processed with a milk-based extender with or without gentamicin (1g/l). Pseudomonas (Ps.) aeruginosa, Staphylococcus (St.) aureus, Streptococcus (Sc.) equi subsp. equi (Sc. equi), Sc. equi subsp. zooepidemicus (Sc. zooepidemicus), Sc. dysgalactiae subsp. equisimilis (Sc. equisimilis) or culture medium alone (control) were added. Immediately after addition of bacteria and after storage at 5 degrees C for 24, 48 and 72h, motility, velocity and membrane integrity of diluted semen were determined with a CASA system. After 24h, semen with Ps. aeruginosa and Sc. equisimilis showed significantly lower motility and velocity compared to all other groups; after 72h these differences still existed for Ps. aeruginosa (p<0.05). The percentage of membrane-intact spermatozoa was significantly lower after 24h of storage in spermatozoa incubated with Sc. equisimilis and after 72h with Sc. equisimilis and Ps. aeruginosa. Addition of gentamicin to extender resulted in decreased motility and velocity in semen without addition of bacteria and did not improve motility parameters in semen with bacteria added. In conclusion, certain bacteria may have detrimental effects on semen quality during cooled-storage. These effects are not reduced by addition of gentamicin. Gentamicin can negatively affect spermatozoal function in extended semen during cooled-storage and therefore, optimal concentrations have to be tested for the respective extender medium.

Animals↗

Anti-oxidative status and semen quality during cooled storage in stallions.

Activity of the anti-oxidative enzymes glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT), content of thiobarbituric acid reactive substances (TBARS) and SH-groups were determined in native stallion semen (n = 8 stallions). Semen was then diluted in Kenney extender, EquiPro((R)) extender either with or without addition of N-acetyl cysteine or phosphate-buffered saline (PBS) and stored for 72 h at 5 degrees C. Correlations between initial activity of enzymes and development of semen motility and membrane integrity were calculated. Activities of GSH-Px, SOD and CAT immediately after semen collections were 10.0 +/- 0.6 picokatals, 0.40 +/- 0.03 SOD units and 0.70 +/- 0.05 nanokatals/10(6) spermatozoa respectively. TBARS content was 0.06 +/- 0.01 nmol and SH-group content 1.7 +/- 0.5 mmol/10(6) spermatozoa. The loss of motile spermatozoa during storage did not differ between extenders. N-acetyl cysteine had no effect on semen motility and membrane integrity. The loss in membrane-intact spermatozoa was highest (P < 0.05) in semen diluted in PBS. Motility and membrane integrity after addition of extender were positively correlated with GSH-Px and CAT, indicating that anti-oxidative mechanisms contribute to the initial high percentage of motile and membrane-intact spermatozoa. However, in these samples the decrease in semen quality was most pronounced. No correlations existed between initial activity of anti-oxidative enzymes, peroxidation products and semen quality during storage. This indicates that once extender has been added, peroxidative damage to sperm membranes is not the predominant cause of losses in semen quality.

Animals↗

Developments in European horse breeding and consequences for veterinarians in equine reproduction.

The liberalization of European animal breeding legislation and an increasing diversity of equestrian sports have led to a constant rise in the number of horse breeds and breed registries. In addition to the trend towards more and smaller breed registries, there is another trend towards an international expansion of the bigger established sport horse breeds. Regional breeds, at least in smaller countries, may no longer be able to run an independent breeding programme. The typical horse breeder, in the future, will be a female and qualified in equestrian sports. Artificial insemination (AI) mainly with fresh or cooled-transported semen has become a major breeding tool, allowing breeders all over Europe to benefit from the best stallions of most breeds. New AI techniques such as low-dose insemination may remain restricted to individual stallions and also the interest of breeding programmes in sex determination of foals via semen sorting is limited. Embryo transfer and associated techniques, although allowed by most breeds, have not contributed significantly to genetic progress in European sport horses so far. A potential use of cloning may be to produce gonad-intact copies from geldings that have performed to a superior level. With a more open and international structure of horse breeding and increased use of AI, equine reproduction and biotechnology should be emphasized by veterinary curricula and continuing professional education programmes.

Animals↗

LH and IGF-1 release during oestrus and early luteal phase in lactating and non-lactating horse mares.

The aim of the present study was to determine effects of lactation on basal LH and IGF-1 concentrations and on the LH response to a GnRH-analogue at different stages of the oestrous cycle in mares. A total of 17 cyclic Haflinger mares were included in the study. Experiments were performed on lactating mares in first postpartum oestrus, the subsequent early luteal phase, and second postpartum oestrus. Non-lactating mares were used in oestrus and early luteal phase. Blood samples were taken for 1 h at 15 min intervals. Mares were then injected with the GnRH-analogue buserelin (GnRHa; 5 microg i.v.) and blood samples were drawn every 15 min for further 2 h. LH in all samples and basal IGF-1-concentrations were determined by RIA. In lactating mares, basal LH concentrations during the early luteal phase tended to be lower (p = 0.07) and the LH response to GnRHa, calculated as area under the curve, was significantly less pronounced compared to non-lactating mares (p < 0.01). As well in lactating mares, the basal LH concentration between first early luteal phase and second oestrus differed significantly (p < 0.05) and the net response to GnRHa was significantly lower between first oestrus as well as second oestrus and first early luteal phase (p < 0.05) but not between first and second oestrous postpartum. Within the group of non-lactating mares, the LH response to GnRHa was as well significantly lower during oestrus than during early luteal phase (p < 0.01). IGF-1 concentrations differed neither between groups nor stages of the cycle within groups. In conclusion, basal and GnRHa-stimulated LH release in lactating mares is lower than in non-lactating mares. This difference, however, occurs only in the early luteal phase. In lactating mares, concentrations of LH appear adequate to allow ovulation to occur.

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Effect of clenbuterol on the clearance of particles of charcoal (4 to 90 microm) from the uteri of mares.

The failure of clearance mechanisms in the mare's uterus results in persistent inflammation and is considered a major cause of subfertility. Eighteen mares, of which three were susceptible to endometritis and four had been ovariectomised, underwent charcoal clearance testing to evaluate their clearance mechanisms. This consisted of installing 500 mg of charcoal (particle size 4 to 90 microm) added to 50 ml of phosphate-buffered saline (PBS) into the uterus. Forty-eight hours later the uterus was flushed out with 0.0012 per cent methylene blue in 50 ml of PBS for determination of the diluting factor by photospectrometry. Flush volume, pH, specific gravity and pellet size were all analysed. To investigate the effect of a beta2-adrenergic agonist on the ability of genitally healthy oestrous mares to eliminate a suspension of charcoal from the uterus, four genitally healthy mares with appropriate charcoal clearance were also subjected to clearance testing following intravenous administration of 0.8 microg/kg of clenbuterol every 12 hours and 1 microg/kg of clenbuterol every eight hours. All parameters were within their normal range following clenbuterol treatment. However, minimal but significant differences in pre- and post-treatment values regarding fluid volume and extinction rate were recorded.

Animals↗

Acute insulin-induced hypoglycaemia does not alter IGF-1 and LH release in cyclic mares.

Lactation in the mare is associated with changes in the release of metabolic as well as reproductive hormones. Plasma glucose concentration is constantly reduced in lactating compared with non-lactating mares. Several metabolic signals have been proposed to link nutrition and somatic metabolism with reproductive function. The following experiment was performed to study the effect of acute hypoglycaemia on the release of insulin-like growth factor-1 (IGF-1) and luteinizing hormone (LH) in cyclic mares. Different doses of insulin (0.1 and 0.2 IU/kg body weight) were given to induce a decrease in plasma glucose concentration, as existent in lactating mares. All horses treated with insulin developed a hypoglycaemia over a time period of nearly 10 h. The IGF-1 and LH were analysed before and after insulin administration. At no point of time, a significant difference between the two insulin treatments and the control treatment was observed. Therefore, the hypoglycaemic horse is apparently able to provide the brain with sufficient glucose. Short-term hypoglycaemia does not affect the hypothalamo-pituitary-ovarian axis, and concentrations of IGF-1 and LH remained stable during insulin-induced hypoglycaemia. An acute change in plasma glucose concentration is thus not or at least not the only metabolic signal that links nutrition and somatic metabolism with reproductive function in the horse mare.

Animals↗

Matrix metalloproteinase 2 (MMP-2) and tissue transglutaminase (TG 2) are expressed in periglandular fibrosis in horse mares with endometrosis.

Periglandular arrangement of myofibroblasts, associated with the deposition of extracellular matrix (ECM), is a cardinal feature of endometrosis in mares. We hypothesized that a disturbance in the expression of matrix degrading enzymes such as matrix metalloproteinases (MMP's) and matrix cross-linking proteins might lead to an imbalance in deposition and degradation of extracellular matrix components and thereby accentuate degeneration. Therefore, distributions of MMP-2, capable of collagen IV and laminin degradation, and tissue transglutaminase (TG2), a cross-linker of extracellular matrix proteins, were investigated by means of immunohistochemistry on uterine biopsies of healthy mares and animals with endometrosis. It was illustrated that both proteins were present in fibrotic regions of affected endometria, and that they were in most cases colocalized. Periglandular MMP-2 expression was significantly associated with dilated and fibrotic uterine glands. Furthermore, MMP-2 and TG 2 were demonstrated in the stratum compactum of healthy and endometrotic endometria. Gelatin zymography proved that active and inactive pro-form of MMP-2 were present in all examined samples with significantly higher amounts of total and active MMP-2 in affected endometria. TG 2-activity, determined by an in situ assay, was found in cases of severe periglandular fibrosis. We suggest that both enzymes play a major role in changes that occur in ECM homeostasis in endometrial fibrotic regions.

Animals↗

Mineralised deposits in the uterine glands of mares with chronic endometrial degeneration.

Chronic degenerative disease of the mare's endometrium is characterised by changes in the uterine glands, including cystic dilation, hyperplasia and periglandular fibrosis. Endometrial biopsies were taken from 23 mares with different grades of endometrial degeneration. Solid structures were identified within the lumina of the uterine glands and shown to be calcified by histochemical staining. Most of them were not homogenous but composed of a mixture of mineral and organic substances. Further examinations of these mineralised structures by immunohistochemical methods revealed the presence of the non-collagenous matrix proteins osteopontin, osteonectin and bone sialoprotein, which are known to be involved in calcification processes such as urolithiosis. Osteopontin and bone sialoprotein were identified within the calculi, frequently arranged in concentric layers. Osteonectin was the only matrix protein that was also present in the glandular epithelium. Osteocalcin was not found in either the calculi or the glandular epithelial cells.

Animals↗

Effects of lactation on metabolic and reproductive hormones in Lipizzaner mares.

In this study, growth hormone (GH), insulin-like growth factor 1 (IGF-1), leptin, luteinising hormone (LH) and prolactin were analyzed in mares from late pregnancy throughout lactation (group 1, n=46) and in non-lactating mares (group 2, n=11). Plasma GH concentrations in group 1 mares during gestation and lactation were lower than in mares of group 2 (P<0.05). Highest IGF-1 levels were found in lactating mares in the week of foaling. IGF-1 concentrations decreased continuously thereafter. Plasma leptin concentrations decreased after foaling and, for 4 weeks, were lower in lactating than in non-lactating mares (P<0.05). Reduced leptin concentrations may promote feed intake and allow lactating mares to avoid an energy deficit. In group 1 mares, prolactin concentrations reached a maximum in the week of foaling and decreased rapidly thereafter. Plasma LH concentrations in group 1 mares before foaling were lower than at corresponding times in group 2 (P<0.05). LH concentrations then increased and did no longer differ from group 2 until week 2 postpartum. This increase may contribute to the resumption of cyclic ovarian activity in postpartum mares. Subsequently, LH levels in lactating mares decreased again (P<0.05). Increased IGF-1 concentrations early postpartum might contribute to ovarian stimulation while reduced IGF-1 and GH concentrations later in lactation might cause reduced stimulation. The changes in somatotrophic hormones could thus explain, at least in part, a more pronounced stimulation of ovarian function early postpartum than during the following months of lactation.

Animals↗

Application of techniques for sperm selection in fresh and frozen-thawed stallion semen.

The objective of this research was to improve the techniques in processing chilled and frozen-thawed horse semen. In a preliminary experiment (Exp. I), different techniques for sperm selection and preparation [Swim-up, Glass wool (GW) filtration, Glass wool Sephadex (GWS) filtration; Percoll] were tested for their suitability for equine spermatozoa and results were compared with the routine procedure by dilution (Exp. I). In the main experiment (Exp. II), two sperm preparation techniques (GWS, Leucosorb) refering to the results of Exp. I and a previous study of our group (Pferdcheilkunde 1996 12, 773) were selected for processing complete ejaculates either for cooled-storage or cryopreservation. In a third experiment (Exp. III), pregnancy rates from inseminations with semen processed according to the techniques tested in Exp. II were compared with those obtained with semen processed according to routine procedures. In Exp. I (six stallions, six ejaculates/stallion), between 48 and 92% of spermatozoa were lost following the different sperm selection procedures (p < 0.05). Preparation of sperm increased percentage of progressively motile spermatozoa (pms) [Swim-up, GW, GWS vs dilution, Percoll (p < 0.05)] and decreased percentage of sperm head abnormalities [Swim-up, GW, GWS vs dilution, Percoll (p < 0.05)] probably by not improving the quality of individual cells, but by elimination of spermatozoa of inferior quality. In Exp. II (eight stallions, three ejaculates/stallion) Leucosorb and GWS procedures allowed the filtration of large volumes (extended ejaculates) for routine laboratory practice. GWS and Leucosorb filtration resulted in increased motility, membrane integrity and sperm viability after storage of spermatozoa until 48 h at +5 degrees C when compared with control (diluted) and centrifuged semen (p < 0.05). Significantly more spermatozoa were recovered after centrifugation (87.8 +/- 15.4%) compared with GWS (63.5 +/- 18.6%) and Leucosorb filtration (53.6 +/- 22.3%). GWS or Leucosorb procedure resulted in successful cryopreservation of stallion semen without centrifugation for removal of seminal plasma. The per cycle conception rate of inseminated mares using 200 x 106 pms transferred within 8 h after collection of semen was not affected by GWS filtration or Leucosorb separation when compared with centrifugation (n.s.; Exp. III). In conclusion, GWS and Leucosorb filtration results in the improvement of semen quality and should be considered as a method for stallion semen processing. Additional studies are needed for the evaluation of potentially higher fertilizing ability of stallion spermatozoa separated by techniques for sperm selection.

Animals↗

Lectin binding patterns in normal canine endometrium and in bitches with pyometra and cystic endometrial hyperplasia.

Cystic endometrial hyperplasia (CEH) and pyometra in the bitch are dioestral syndromes, supposed to be caused by hormonal disturbances and changes in endometrial steroid hormone receptor levels. Histologically, the endometria show cystic dilated glands and, if bacteria succeed in invading the uterus, pyometra may develop in the following metoestrus. In this study, lectin histochemistry was performed on paraffin sections to compare carbohydrate expression of uterine glands and surface epithelium in healthy dogs and in dogs with CEH and pyometra. Lectin binding is a useful tool to identify glycoconjugates, especially of the glycocalyx, which has essential functions in the endometrium during reproduction. Uterine tissue was obtained from 18 healthy bitches in metoestrus or anoestrus and 18 bitches with a clinical diagnosis of CEH or pyometra. Normal endometria showed cycle-dependent changes in SBA, PNA, HPA and UEA binding during metoestrus and anoestrus. LCA did not show cycle-dependent changes and WGA bound to Golgi regions in the apical parts of surface epithelial cells only in metoestrous. Endometria with inflammatory alterations lost cycle-specific lectin binding patterns and, with increasing severity of pathological changes, showed a marked decrease in binding intensity to the glandular and surface epithelial glycocalyx and secretions. In dogs with CEH, unaltered glands with generally strong lectin binding to the glycocoalyx and Golgi regions were found adjacent to altered glands. The decrease of lectin binding in pyometra cases is supposed to be a result of glandular exhaustion after cystic hyperplasia. In addition, bacterial adhesion to sugar residues on the uterine surface epithelium might impede lectin binding.

Animals↗

[Age- and education-specific reference values for the cognitive test of the SIDAM (Structured interview for the diagnosis of dementia of the Alzheimer type, multi-infarct dementia and dementias of other etiology according to ICD-10 and DSM-IV)].

The SIDAM (Structured Interview for the diagnosis of Dementia of the Alzheimer type, Multi-infarct dementia and dementias of other etiology according to ICD-10 and DSM-IV) is a standardized interview for the diagnosis of dementia. It can also be used as a screening instrument for the diagnosis of different syndromes of dementia and mild cognitive impairment. At present there is no age- or education-specific standardization. This report presents age- and education-specific norms for the cognitive assessment of the SIDAM, obtained in a population-based sample of elderly people aged 75 and over (n=1001).

Age Factors↗

[Adaptation of a dementia test for use in visually handicapped persons exemplified by SIDAM (Structured Interview for the Diagnosis of Alzheimer disease, Multi-Infarct Dementia and Dementias of other Etiology)].

In epidemiological field studies on the prevalence and incidence of dementia, the problem of cognitive testing of visually impaired individuals is rarely discussed. In the Leipzig Longitudinal Study of the Aged (LEILA 75+) a version of the SIDAM (SIDAM-Structured Interview for the Diagnosis of dementia of the Alzheimer type, Multi-infarct dementia and dementias of other etiology) for the visually impaired was employed from which all items requiring image processing had been omitted (SIDAM-blind). In order to be able to interpret the test results, the final scores for the full SIDAM were estimated by linear transformation of the scores in the blind-version. The method of linear transformation is based on certain theoretical assumptions which are examined in this paper. Linear transformation of scores has proved to be a valid procedure only for individuals with high cognitive performances. Thus, an evaluation of estimated scores based on the norms for the original SIDAM has limitations. Consequently, age-specific norms for the SIDAM-blind are presented. Sensitivities and specificities for different cut-off points used to discriminate between demented and non-demented vision-impaired individuals are given.

Aged↗

Dopaminergic and opioidergic regulation of gonadotropin and prolactin release in stallions.

In the non-breeding season, LH release is reduced via dopaminergic systems in the ram. On the other hand, our previous studies demonstrated an opioidergic inhibition of LH release in stallions outside the breeding season. Thus, in the present study we investigated the dopaminergic regulation of LH and prolactin secretion in stallions, considering interactions between dopamine and opioids. To achieve this, stallions (n=8) were treated with the dopamine antagonist sulpiride (0.6 mg/kg), the opioid antagonist naloxone (0.5 mg/kg), sulpiride plus naloxone or saline in December, March and June. Two hours after the respective treatments, they received a GnRH agonist. Sulpiride induced a significant prolactin release which was most pronounced in December, indicating seasonal variations in the inhibition of prolactin secretion by dopaminergic systems. Prolactin concentrations were not changed by naloxone. Neither during nor outside the breeding season, a dopaminergic regulation of LH release could be demonstrated. In contrast, naloxone caused a significant (p < 0.05) LH release, confirming an opioidergic inhibition of LH release. In conclusion, opioidergic regulation of LH and dopaminergic inhibition of prolactin secretion undergo seasonal changes. Neither during nor outside the breeding season, dopaminergic effects on LH release exist in the stallion.

Animals↗

Prevalence of dementia according to DSM-III-R and ICD-10: results of the Leipzig Longitudinal Study of the Aged (LEILA75+) Part 1.

BACKGROUND: The prevalence of dementia diagnosis according to ICD-10 and DSM-III-R in population surveys remains poorly understood. AIMS: To report and compare prevalence rates according to DSM-III-R and ICD-10. METHOD: A population-based sample (n=1692, age 75+years) was investigated by a Structured Interview for Diagnosis of Dementia of Alzheimer Type, Multiinfarct Dementia and Dementia of other Aetiology according to DSM-III-R and ICD-10 (SIDAM). RESULTS: Whereas 17.4% (95% CI=15.9-19.5) of individuals aged 75+ years suffer from dementia according to DSM-III-R, only 12.4% (95% CI=10.6-14.2) are diagnosed as having dementia according to ICD-10. The results revealed lower ICD-10 rates in all investigated age groups. The largest differences appear in the oldest of the elderly. CONCLUSIONS: The ICD-10 sets a higher threshold for dementia diagnosis. Larger differences in the eldest age groups might reflect difficulties in applying case definitions, especially in those beyond 90 years old.

Age Distribution↗

Incidence of dementia according to DSM-III-R and ICD-10: results of the Leipzig Longitudinal Study of the Aged (LEILA75+), Part 2.

BACKGROUND: The impact of different case definitions on incidence rates remains unclear. AIMS: To compare incidence rates of dementia according to DSM-III-R and ICD-10. METHOD: A two-wave community study was conducted (n=1692, age 75+ years follow-up period 1.6 years). Cognitive function was assessed by the Structured Interview for Diagnosis of Dementia of Alzheimer Type, Multiinfarct Dementia and Dementia of other Aetiology according to ICD-10 and DSM-III-R (SIDAM). RESULTS: The annual incidence rate for dementia by applying different case definitions was found to be quite similar (DSM-III-R: 47.4 (95% CI=36.1-61.2) per 1000 person-years; ICD-10: 45.8 (95% CI=35.0-59.0) per 1000 person-years). Age-specific incidence rates increase steeply with age. CONCLUSIONS: The impact of different case definitions on incidence rates of dementia appears limited if case definitions and case-finding procedures at baseline and follow-up are applied consistently.

Age Distribution↗

Opioidergic inhibition of luteinising hormone and prolactin release changes during pregnancy in pony mares.

In equine species, luteinising hormone (LH) and prolactin (PRL) release are reduced throughout pregnancy but increase at foaling. The present experiments were designed to study a possible opioidergic regulation of LH and PRL release in pregnant Shetland mares (n=6). At various stages of pregnancy (days 26.4+/-0.6, 75.4+/-5.4, 171.8+/-2.4, 226.2+/-4.8, 282.7+/-3.4 and 319.8+/-2.1), mares were injected with the opioid antagonist naloxone (0.5 mg/kg body weight) and saline. The two treatments were always separated by 2 days, and mares served as their own controls. Two hours after being given naloxone and saline, mares were given the gonadotrophin-releasing hormone (GnRH) analogue buserelin (5 microg per animal). The naloxone experiment was repeated at 2 days after foaling. Blood for the determination of LH and PRL was withdrawn at 15 min intervals for 240 min, and naloxone or saline was injected after 60 min. Naloxone induced significant (P<0.05) LH release on days 172, 226 and 283 of pregnancy but not on days 26, 76 and 320 and 2 days after foaling. Buserelin caused a significant (P<0.05) increase in plasma LH concentrations on days 172, 226, 282 and 320 of pregnancy. The experiments indicate that endogenous opioids are involved in the inhibition of LH release during the second half of pregnancy in equine species. The deactivation of opioid effects on LH release might be a prerequisite for the onset of ovarian activity postpartum. Plasma PRL concentrations increased significantly (P<0.05) after naloxone administration on days 226, 282 and 320 of pregnancy. The naloxone-induced PRL release was most pronounced towards term, indicating an increase in the naloxone-releasable pool and/or the absence of other PRL-release inhibitory mechanisms.

Animals↗