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991.
Background Induction of multiple ovulations, or superovulation, may potentially increase the efficiency of equine embryo transfer programs. Our objective was to investigate the effects of equine follicle‐stimulating hormone (eFSH) treatment on the success rate of embryo transfer programs in mares. Methods In the research facility of the University of Saskatchewan, Canada, we studied 12 donor mares and 37 recipient mares during the physiological breeding season. Donor mares were used in two consecutive oestrous cycles: the first served as the control cycle and in the second an eFSH regimen was applied (eFSH cycle). In the control cycle, mares were administered human chorionic gonadotropin (hCG) to induce ovulation when a follicle ≥35 mm in diameter was detected by transrectal ultrasonographic examination. In the second oestrous cycle, twice‐daily eFSH treatment was initiated when a follicle ≥25 mm was detected and treatment ceased when a follicle ≥35 mm was present, at which time hCG was administered. All donor mares were artificially inseminated while in oestrus using fresh semen collected from a stallion of proven fertility. At 8 days post‐ovulation, embryos were recovered transcervically and transferred individually to the uterus of a synchronised recipient mare. Results The eFSH treatment stimulated the ovary and resulted in greater numbers of ovulations and recovered embryos; however the recovered embryos tended to have a lower morphological grade than the control embryos, and the recipient pregnancy rate per transferred embryo was lower than anticipated. Conclusion The numbers of recipient pregnancies and foals born that resulted from eFSH treatment were not different from the control.  相似文献   
992.
In Iberia there are 51 officially recognized cattle breeds of which 15 are found in Portugal and 38 in Spain. We present here a comprehensive analysis of the genetic diversity and structure of Iberian cattle. Forty of these breeds were genotyped with 19 highly polymorphic microsatellite markers. Asturiana de los Valles displayed the greatest allelic diversity and Mallorquina the least. Unbiased heterozygosity values ranged from 0.596 to 0.787. The network based on Reynolds distances was star-shaped with few pairs of interrelated breeds and a clear cluster of 4 breeds (Alistana/Arouquesa/Marinhoa/Mirandesa). The analysis of the genetic structure of Iberian cattle indicated that the most probable number of population clusters included in the study would be 36. Distance results were supported by the STRUCTURE software indicating a relatively recent origin or possible crossbreeding or both between pairs or small groups of breeds. Five clusters included 2 different breeds (Betizu/Pirenaica, Morucha/Avile?a, Parda de Monta?a/Bruna de los Pirineos, Barros?/Cachena, and Toro de Lidia/Brava de Lide), 3 breeds (Berrenda en Negro, Negra Andaluza, and Mertolenga) were divided in 2 independent clusters each, and 2 breeds were considered admixed (Asturiana de los Valles and Berrenda en Colorado). Individual assignation to breeds was not possible in the 2 admixed breeds and the pair Parda de Monta?a/Bruna de los Pirineos. The relationship between Iberian cattle reflects their geographical origin rather than their morphotypes. Exceptions to this geographic clustering are most probably a consequence of crossbreeding with foreign breeds. The relative genetic isolation within their geographical origin, the consequent genetic drift, the adaptation to specific environment and production systems, and the influence of African and European cattle have contributed to the current genetic status of Iberian cattle, which are grouped according to their geographical origin. The greater degree of admixture observed in some breeds should be taken into account before using molecular markers for genetic assignment of individuals to breeds.  相似文献   
993.
994.
995.
The US3 protein is a unique protein kinase only present in the Alphaherpesvirinae subfamily of the herpesviruses. Studies performed with several alphaherpesviruses demonstrated that the US3 protein is involved in cytoskeleton modifications during viral infection and displays anti-apoptotic activity. However, the US3 protein of BoHV-5 has not been studied up to now. As reported for other alphaherpesviruses, our results showed that BoHV-5 US3 confers resistance against apoptosis and induces cytoskeletal reorganization leading to cell rounding, actin stress fiber breakdown and cell projections that interconnect cells. The expression of a kinase-dead version of BoHV-5 US3 showed that the anti-apoptotic activity and the induction of cell projections are kinase-dependent whereas kinase activity is not absolutely required for actin stress fiber breakdown. Besides, the kinase-dead version of US3, but not the wild type protein, was found excluded from the nucleus. These results constitute the first report on the BoHV-5 US3 functions, and highlight that there are functional differences and similarities among US3 proteins of different alphaherpesviruses.  相似文献   
996.
There is a global move from individual to group housing of gestating sows. In the European Union, individual gestating stalls will be banned by 2013. Just like in other industrialized regions, these stalls have been the standard housing system for intensively kept sows from the 1960s onward in the Flemish region of Belgium. Because the socioeconomic consequences for the pig industry may be far-reaching and because farmer attitude may influence the realization of the hoped-for improvement in animal welfare in practice, we conducted a survey from 2003 until 2009 among representative samples of Flemish pig producers every 2 yr. The share of farms with group housing increased from 10.5% in 2003 to 29.8% in 2007, but then dropped to 24.6% in 2009. It appears that after 2005 users of old group housing systems in particular stopped farming. Because sow herd size increased more on farms with vs. without group housing and because the proportion of the herd that was group-housed also tended to increase between 2003 to 2009, the change to group housing took place faster when expressed at the level of the sow (from 9.1% in 2003 to 34.1% in 2009) instead of farm. The percentage of farmers planning to convert to group housing within 2 yr was 4.1% in 2003, and 6 to 7% thereafter. These were typically young farmers (P = 0.006) with a large sow herd (P < 0.001) and with a likely successor (P = 0.03). Free access stalls were the most common group housing system (31% of farms, 37% of sows). Their popularity is expected to increase further at the expense of electronic feeding stations, ad libitum feeding, and stalls/troughs with manual feed delivery. User satisfaction was generally high but depended on whether or not all gestating sows were kept in group (P < 0.001), the provisioning of environmental enrichment (P = 0.057), and the age (P = 0.012) and type (P = 0.016) of system. The main criteria for choosing a certain group housing system were the investment costs and sow health and welfare. The importance of economic reasons (P = 0.007) and type of labor (P = 0.043) decreased with the age of the system. In 2003 and 2005 the main reason for not having converted to group housing was that farmers would stop keeping sows by 2013. In 2007 and 2009 the reasons mainly concerned uncertainty about the future and maximally delaying the conversion. Belgium is one of the European Union countries where the pig industry is expected to undergo drastic changes during the few years remaining before the ban on individual housing.  相似文献   
997.
The prevalence of canine echinococcosis appears to have been increasing in mid/south Wales in recent years - raising the concern of a potential resurgence in transmission to humans. A campaign was therefore conducted in 2008 in order to provide dogs in South Powys with anthelmintics, estimate the coproantigen prevalence amongst these dogs, and evaluate potential risk factors for coproantigen positivity. The coproantigen prevalence identified in these dogs (n=577) was 10.6% (95% confidence interval 7.6-13.5%), with 20.6% (15.6-25.7%) of farms (n=247) containing at least one coproantigen-positive dog. Further spatial investigation identified considerable spatial heterogeneity amongst the farms, with an increased coproantigen prevalence in the regions of Brecknockshire and the Brecon Beacons National Park. Within these areas, there was strong evidence of an increase in coproantigen prevalence, compared to that found in a study conducted in 2002. Finally, a mixed effects logistic regression model identified increased roaming behaviour and decreased dog weight as being associated with increased odds of coproantigen positivity, whereas pet dogs on some farms had similar odds of infection to working dogs. Further surveillance efforts in South Powys are required and should also include the northern areas of Gwent and Glamorgan.  相似文献   
998.
999.
A fatal case of eosinophilic and granulomatous meningoencephalitis caused by the free-living panagrolaimid nematode Halicephalobus gingivalis is reported in a 10-year-old Welsh gelding in the United Kingdom. Clinical examination first revealed behavioural abnormalities which rapidly progressed to severe ataxia, reduced mentation status and cranial nerve signs. Despite symptomatic treatment no amelioration of neurological signs was achieved and the horse was subjected to euthanasia. A complete post mortem examination revealed eosinophilic and granulomatous meningoencephalitis mainly affecting the cerebellum and brain stem with intralesional adult nematodes, larvae and eggs. There was also eosinophilic meningitis of the cervical spinal cord. The intralesional nematodes were morphologically consistent with the panagrolaimid nematode H. gingivalis. Although infection by this facultative neurotropic parasite is extremely rare, it needs to be considered in the differential diagnosis of central nervous signs in horses and, in particular, other equine helminthic infection of the central nervous system. This fatal case is unusual since lesions were locally very extensive and the nematodes did not colonise haematogenously to other organs as seen often in equine halicephalobosis. As the taxonomy of H. gingivalis has changed and some recent reports in the literature still refer to this species as Micronema deletrix or Halicephalobus deletrix, we here provide a short update of the species and some insights on the order Tylenchida, which contains free-living nematodes with parasitic tendencies.  相似文献   
1000.
Reasons for performing study: Standing surgical procedures are being employed to an ever‐greater extent in horses. Pneumoperitoneum during abdominal surgery might adversely affect the work of breathing. Objectives: To determine whether development of pneumoperitoneum during abdominal surgery adversely influences the work of breathing. Methods: Eight healthy mature horses were equipped with carotid artery and thoracic vena cava catheters and an intraluminal manometry system. The following measurements were obtained before and at +5, +10, +15 and +30 min following establishment of pneumoperitoneum by paralumbar puncture using an 8 gauge needle: vital signs, oesophageal pressure, gastric pressure, arterial and central venous blood pressures, and arterial and mixed venous blood gas analyses. Results: Significant changes in oesophageal pressure, central venous pressure and results of arterial and mixed venous blood gas analysis were not detected. Arterial diastolic and mean pressures and rectal temperature increased slightly (P≤0.05). Conclusions: Passive pneumoperitoneum did not adversely affect breathing mechanics or haemodynamic variables under experimental conditions. Changes in arterial pressure could have occurred as a response to the passive pneumoperitoneum or be related to handling stress. Subtle variations in rectal temperature were not clinically relevant and likely resulted from stress associated with restraint. Potential relevance: It is unlikely that mature horses will develop signs of respiratory difficulty as a result of the development of passive pneumoperitoneum during standing laparoscopy.  相似文献   
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