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A clinical outbreak of infectious bovine rhinotracheitis with a morbidity of 11.3% in unvaccinated bulls of a test station is described. The outbreak began explosively in one pen and appeared in others over a period of two weeks. After intranasal vaccination of all bulls, the sporadic occurrence of clinical infectious bovine rhinotracheitis ceased. Although no animals died as a result of infectious bovine rhinotracheitis, the periodic weighing necessary in a bull test station revealed that affected bulls were set back in their average daily rate of gain. While on test, affected Angus bulls never returned to an average daily gain comparable to unaffected bulls of the same breed.  相似文献   
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A multitracer study of a small aquifer in northern Switzerland indicates that the atmosphere in central Europe cooled by at least 5 degreesC during the last glacial period. The relation between oxygen isotope ratios (delta18O) and recharge temperatures reconstructed for this period is similar to the present-day one if a shift in the delta18O value of the oceans during the ice age is taken into account. This similarity suggests that the present-day delta18O-temperature relation can be used to reconstruct paleoclimate conditions in northern Switzerland. A gap in calculated groundwater age between about 17,000 and 25,000 years before the present indicates that during the last glacial maximum, local groundwater recharge was prevented by overlying glaciers.  相似文献   
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Pre‐natal glucocorticoids are used in women at risk of preterm delivery to induce foetal lung maturation. However, glucocorticoids can produce negative outcomes for other tissues such as the reproductive system. We therefore tested the effects of pre‐natal betamethasone on testicular morphology and apoptotic protein immune expression during pre‐ and post‐natal development. Pregnant ewes (n = 42) bearing singleton male foetuses were randomly allocated to receive intramuscular injections of saline or betamethasone (0. 5 mg/kg) at 104, 111 and 118 days of gestation (DG). Testes were collected at 121 and 132 DG, and at 45 and 90 post‐natal days (PD) and subjected to morphometric analysis (volume densities of sex cords and interstitial tissues; sex cord diameter). Immunohistochemistry (% stained area) was used to assess active caspase‐3, Bax, Bcl‐2 and cell‐cycle proteins (PCNA). Compared with control values, betamethasone treatment decreased sex cord diameter at 121 DG, 45 and 90 PD, and sex cord volume at 90 PD. Active caspase‐3 was decreased by betamethasone at 121 DG and 90 PD, but Bax was increased in all betamethasone groups. Bcl‐2 and PCNA decreased in the betamethasone groups at 121 DG and 45 PD, but increased at 132 DG and 90 PD. We conclude that high levels of pre‐natally administered glucocorticoid reduce foetal testicular development, perhaps via changes in the balance between pro‐ and anti‐apoptotic proteins and cell‐cycle proteins. These outcomes could compromise the future spermatogenic potential of male offspring.  相似文献   
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Thirty-four mixed breed horses from two separate farms showed signs of abdominal discomfort, pyrexia and dehydration after being exposed to a new batch of 14% complete horse feed. A new batch of cattle feed from the same manufacturer resulted in dairy cows showing depression, a drop in milk production and diarrhoea. Examination of both diets revealed the presence of white kidney beans (Phaseolus vulgaris). Inclusion of raw beans of this genus in animal feeds is to be avoided.  相似文献   
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Northern blot analysis suggested that the boar epididymis produces closely related counterparts to human epididymal proteins HE1, HE3, HE4, HE5 and HE12. ‘Full‐length’ cloning by nucleic acid and amino acid sequence similarity was achieved by RT‐PCR methods in the case of the porcine counterparts of HE3 and HE4, while the homologues of HE5 and HE12, despite their cross‐hybridization during Northern blot analysis, have not yet been cloned. The two novel porcine cDNAs were derived from moderately abundant epididymal mRNAs that were 75 and 83% identical to HE3 and HE4 cDNAs, respectively. To emphasize their relationship to the corresponding HEs, they were named Se3 and Se4 cDNAs. Their open reading frames predicted small secretory proteins with 55% (Se3) and 76% (Se4) conserved amino acids. Monospecific antipeptide antibodies to HE secretory proteins identified He3‐ and HE12‐related proteins on Western blots of porcine epididymal fluid and semen. Both Northern and Western analyses indicated that the Se proteins were produced in a regionalized pattern and accumulated in the cauda fluid.  相似文献   
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Hypoglycin A (HGA) was detected in blood and urine of a horse suffering from atypical myopathy (AM; Day 2, serum, 8290 μg/l; urine: Day 1, 574, Day 2, 742 μg/l) and in its cograzing partners with a high variability (46–1570 μg/l serum). Over the period of disease, the level of the toxic metabolites (methylencyclopropylacetic acid [MCPA]‐conjugates) increased in body fluids of the AM horse (MCPA‐carnitine: Day 2, 0.246, Day 3, 0.581 μmol/l serum; MCPA‐carnitine: Day 2, 0.621, Day 3, 0.884 μmol/mmol creatinine in urine) and HGA decreased rapidly (Day 3, 2430 μg/l serum). In cograzing horses MCPA‐conjugates were not detected. HGA in seeds ranged from 268 to 367 μg/g. Although HGA was present in body fluids of healthy cograzing horses, MCPA‐conjugates were not detectable, in contrast to the AM horse. Therefore, increasing concentrations of MCPA‐conjugates are supposed to be linked with the onset of AM and both parameters seem to indicate the clinical stage of disease. However, detection of HGA in body fluids of cograzing horses might be a promising step in preventing the disease.  相似文献   
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