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21.
In the mid-1980s, Switzerland started a programme to eradicate caprine arthritis-encephalitis - an infectious disease of goats caused by the small ruminant lentivirus (srlv). Since 1996, progress towards eradication has slowed down, owing to infections occurring on farms from which the infection had previously been eliminated. To investigate specific risk factors for these new infections and to improve the eradication programme, a case-control study was conducted. Cases consisted of farms that had been officially free of srlv for at least three consecutive years but on which at least one srlv-seropositive animal had been detected during the annual serological surveys of 2001 and 2002. On all the case and control farms where sheep were housed together with goats, a subset of sheep was screened for antibodies to srlv. Potential risk factors were analysed in a logistic regression model; the results indicated that close contact with srlv-seropositive sheep was highly correlated with seroconversion in srlv-seronegative goat herds (odds ratio=26.9), supporting the hypothesis that srlv can be transmitted between sheep and goats, and suggesting that the measures taken so far will not lead to the complete eradication of srlv from Switzerland within the next few years.  相似文献   
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Rats in a low-ceiling shuttlebox initially show a lower level of learning than rats in a high-ceiling box. After an hour's interruption of conditioning the performance of animals in low-ceiling boxes improves and avoidance is slightly more efficient than in the unimproved performance of animals in high-ceiling boxes. Box height also interacts significantly with length of box.  相似文献   
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Cloned mammals suffer from high rates of placental abnormality and foetal loss during pregnancy. We previously used 2-D gel electrophoresis and mass spectrometry for global proteomic analysis of cloned and normal bovine placentae to identify differential protein expression patterns. Here, we used Western blot analysis to confirm the expression levels of several pregnancy-related proteins putatively identified as being differentially expressed in somatic cell nuclear transfer (SCNT) vs normal bovine placentae. The expression levels of tissue inhibitor of metalloproteinase-2 (TIMP-2), its downstream protein, matrix metalloproteinase-2 (MMP-2), superoxide dismutase (SOD), vimentin and plasminogen activator inhibitor-1 (PAI) were analysed in the placentae of SCNT cloned Korean native cattle that died immediately after birth and in normal placentae obtained by AI. Our results revealed that TIMP-2 and SOD were up-regulated in SCNT placenta compared with normal placenta, whereas MMP-2 levels were comparable in cloned and normal placentae, and vimentin and PAI were significantly down-regulated in SCNT compared with normal placentae. Our results suggest that key proteins of placental development are abnormally expressed in SCNT cloned bovine placentae, probably resulting in abnormal placental function and clonal mortality.  相似文献   
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Bovine viral diarrhoea (BVD) control/eradication programmes based on the test and removal of persistently infected cattle without use of vaccination were first introduced by the Scandinavian countries in the early 1990s. Within the last 10 years the programmes have proven to be very successful and have served as a blueprint for several other European regions. However, in areas with high cattle densities, intense animal trade and high BVD prevalence this control approach is risky, because there is a high probability that herds, which have been cleared of persistently infected (PI) animals and have become partly or fully susceptible to reintroduction of the virus, will come in contact with a BVD virus (BVDV) infected animal. A combination of the test and removal strategy with subsequent systematic vaccination of cattle could overcome this problem. The goals of vaccination in such a programme is protection against reintroduction of BVDV into herds free from PI cattle and foetal protection of pregnant animals accidentally exposed to the virus. Two-step vaccination is based on the use of inactivated BVDV-1 vaccine for priming followed by a live attenuated vaccine booster 4 weeks later. The immune response elicited by such a vaccination scheme has proven to be long lasting and foetal infection after challenge with BVDV-1 and BVDV-2 was prevented in pregnant animals 5 months after vaccination. These findings suggest that the implementation of a two-step vaccination in the initial phase of control programmes in addition to test and removal of PI animals in areas with high cattle densities and endemic BVD is practical and efficacious.  相似文献   
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The case histories, surgical treatment and post–operative progress of twelve dogs with otitis media and/or otitis interna and one dog with an adnexal carcinoma arising within the tympanic bulla are described. Résumé. On décrit les antécédents du cas, le traitement chirurgique et les progrès postopératoires chez douze chiens avec une otite moyenne et/ou une otite interne et chez un chien avec un carcinome des annexes se formant dans la bulle tympanique. Zusammenfassung. Die Krankengëschichte, chirurgische Behandlung und postoperativer Fortschritt von zwǒlf Hunden mit Mittelohrentzǔndung und/oder Innerohrentzùndung und von einem Hund mit Adnexkarzinom, das sich innerhalb der tympanalen Bulla bildete, wurde beschrieben.  相似文献   
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The case histories of 123 dogs with pelvic fractures are reviewed. Eighty–seven dogs were treated conservatively and 28 surgically; the management and results of treatment in each group are described and compared.  相似文献   
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The case histories of 40 dogs with cervical disc protrusions are described. In each case fenestration of the affected disc and prophylactic fenestration of the other cervical discs was carried out. The results of treatment are presented.  相似文献   
29.
This study tested the hypothesis that purebred Boran (Bos indicus) cows and crossbreds of Boran and Holstein respond differently to long-term changes of feeding level in nutrient partitioning to milk and body fat stores. A total of 27 cows of these two genotypes were subjected either to a low or a high feeding level from their first oestrus as heifers until birth of their third calf. Half of the cows of each genotype were then switched to the other feeding level during the third reproduction cycle. If at all, Boran cows responded to a change in the feeding level almost exclusively by a corresponding change in body weight but not milk yield. Crossbred cows kept continuously on the low feeding level had a lower milk yield than those continuously fed the high level, but lost similar amounts of body weight. In crossbred cows, changing the feeding level from high to low was accompanied by a mobilization of body reserves, whereas a change from low to high level resulted mostly in an increase in milk yield. Certain other genotype differences in metabolic response were obvious from differences in body composition and from the metabolic profile either reflected in blood (particularly insulin-like growth factor I) or in adipose tissue (lipoprotein lipase). Reproductive performance differed between genotypes, with shorter lactations associated with earlier occurrences of the first oestrus in the Boran cows. Generally, feeding history appeared to have at least as much influence on energy partitioning as the actual feeding level. In conclusion, purebred Boran cows seem to react to long-term food fluctuations mainly by mobilizing and restoring body fat reserves, whereas cows crossbred with Holstein tend to spend extra energy preferentially for milk production.  相似文献   
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