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11.
Four Irish setters were diagnosed with bilateral retinal degeneration and cataracts at an age ranging from six to 11 years. In three of these dogs, progressive night blindness was reported from an age of eight to 11 years. In the fourth dog, aged six, no signs of visual impairment had been noticed. In all four dogs, the rod-cone dysplasia type 1 (rcd1) mutation was excluded as a cause, using an allele-specific PCR. From their three-generation pedigrees, a familial relationship was detected in three out of four dogs, which were also related to four additional Irish setter dogs with a history and clinical signs suggestive of late-onset progressive retinal degeneration. These results suggest the existence of a possibly hereditary, late-onset, progressive retinal atrophy in the Irish setter breed, that is distinct from rcd1.  相似文献   
12.
The veterinary school admission interview is a widely used selection tool, yet concerns persist about its reliability, validity, and cost. Relative to medicine, optometry, and dentistry schools, veterinary schools have been more likely to conduct panel interviews and to fix the interview's weight in selection decisions, strategies that increase interview validity. This article provides strategies for further increasing the veterinary school interview's validity. Interview reliability and validity studies point to key strategies the veterinary school admissions committee can implement before the interview: (1) establishing the interview's purpose(s); (2) conducting a "job" analysis to identify desirable candidate skills, knowledge, and attributes; (3) developing a structured and panel interview where interviewers, if possible, are blind to other admission data; (4) training interviewers; (5) setting a reasonable interview schedule; and (6) determining methods for analyzing applicant data. During the interview, interviewers should proceed through a structured series of steps: (1) open the interview with a specified agenda; (2) probe for information using structured questions and anchored rating scales; (3) close the interview to allow for candidate questions; and (4) evaluate the interview data. After the interview, the admissions committee should (1) analyze the interview data within and across interviewers and (2) analyze the data across all selection tools in order to assign relative weights to the selection tools.  相似文献   
13.
The effect of feeding sows a starch diet or a diet with a high level of nonstarch polysaccharides (NSP) during gestation, lactation, or both gestation and lactation during the first three parities on reproductive performance, body weight, and backfat was studied. Four-hundred and forty-four postpuberal gilts were allotted to a 2 x 2 x 2 factorial experiment. Treatments were diet composition during gestation (including the weaning-to-estrus interval; G-Starch: 274 g/kg of starch and 123 g/kg of fermentable NSP or G-NSP: 86 g/kg of starch and 300 g/kg of fermentable NSP), diet composition during lactation (L-Starch: 293 g/kg of starch and 113 g/kg of fermentable NSP or L-NSP: 189 g/kg of starch and 216 g/kg of fermentable NSP) and group-housing system during gestation (free access stalls or electronic feeding). Both gestation diets were formulated to be isoenergetic. During lactation, sows were given free access to the lactation diets from d 6 after parturition onwards. Body weight and backfat gains during gestation were lower in sows fed the G-NSP diet than in those fed the G-starch diet (P < 0.001). The effects were more pronounced in the electronic feeding system than in the free access stalls. These results indicate an overestimation of the energy value of fermentable NSP. Body weight and backfat losses during lactation were less in sows fed the G-NSP diet during gestation than in those fed the G-starch diet (P < 0.05),which can be explained by a 0.4 kg/d higher (P < 0.001) feed intake during lactation of the sows fed the G-NSP diet. Sows fed the L-NSP diet lost more backfat during lactation than sows fed the L-starch diet (P < 0.05). The number of total piglets born and live-born piglets was 0.5 piglet higher in sows fed the G-NSP diet than in those fed the G-starch diet (P < 0.05). Lactation diet did not affect the number of total piglets born or live-born piglets. This study shows that, although high NSP diets negatively influence body weight and backfat thickness of the sows, it is possible to feed sows a diet with a high level of fermentable NSP diet during both gestation and lactation without negative effects on reproductive performance. Under the conditions of this study, feeding sows a diet with a high level of fermentable NSP during gestation and a high level of starch during lactation seems the most favorable feeding strategy.  相似文献   
14.
Extrahepatic biliary atresia in a border collie   总被引:2,自引:0,他引:2  
Progressive lameness and leg pain were the predominant clinical signs in a 17-week-old male border collie presented for examination. On clinical investigation, extrahepatic cholestasis in association with rickets due to inadequate vitamin D resorption was diagnosed. The dog was treated parenterally with vitamin D and a cholecystoduodenostomy was performed. At 25 days postsurgery the lameness had resolved and bone structure was radiographically normal. However, at six weeks postsurgery, the dog's condition deteriorated rapidly and euthanasia was finally performed at eight weeks postsurgery. At postmortem examination, Toxocara canis nematodes were found to have invaded the biliary system via the anastomosis between the gallbladder and duodenum, causing biliary and hepatic toxocariasis. The cause of the primary extrahepatic cholestasis was atresia of the common bile duct at the hepatic end. The liver tissue showed microscopic lesions of chronic extrahepatic cholestasis as well as acute inflammation associated with the nematode invasion. There was no postmortem evidence of bone lesions. Extrahepatic biliary atresia is extremely rare in animals and has not been described before in dogs. In contrast, it represents the most common cause of congenital cholestasis in children, occurring in approximately one per 10,000 to 15,000 live births.  相似文献   
15.
In the course of the 1997-1998 CSF epidemic in the Netherlands, two semen collection centres (SCC) became infected. As an eradication strategy for an acute crisis situation, it was concluded that all semen of the boars at the SCCs collected and distributed in the risk period of 28 January to 7 March 1997 was potentially contaminated (suspect semen). As a consequence, a total of 1,680 pig herds, mainly located in the southern part of the Netherlands, were officially declared CSF suspect. The purpose of this study was to investigate whether infection of farms through contaminated semen played a significant role in the CSF epidemic. A total of 123 CSFV infected herds were identified, that had received suspect semen from one or both of the infected SCCs. In 87 out of these 123 infected herds, infection by way of artificial insemination (AI) could be excluded either according to the insemination information or the infection pattern observed. In only 21 herds, infection by way of AI was regarded as possible according to the insemination information and infection pattern. Owing to missing information, no conclusion could be drawn about the possibility of infection of 15 farms by way of AI. Thus, we conclude that at most 36 farms may have been infected through AI during the CSF epidemic in the Netherlands.  相似文献   
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Proliferation assays performed on peripheral blood mononuclear cells (PBMC) are commonly used in experimental and clinical immunology. A prerequisite for an in vitro assay is the ability to obtain relatively pure populations of mononuclear cells from whole blood, as contaminating polymorphonuclear cells may affect the proliferation of lymphocytes. Purification of canine leucocytes from whole blood is associated with difficulties in obtaining pure lymphocytes in high yields. The aim of this study was to optimize the lymphocyte purification from canine whole blood in terms of total cell recovery and purity, while not influencing the proliferation capacity of the isolated cells. To acquire optimal isolation of canine lymphocytes several density gradient media of different densities and osmolalities were examined. For optimal phagocyte removal, pre-treatment of whole blood with carbonyl iron/arabic gum and/or adherence to fibrinogen pre-coated polystyrene tissue flasks were examined. Lectin-induced proliferation was used as measurement of cell activity of the obtained cell fractions after the different separation procedures. Canine blood pre-treated with carbonyl iron/arabic gum followed by density gradient centrifugation with medium 'G' (density: 1.079 g/cm(3), osmolality: 256 mOsm) and adherence to pre-coated polystyrene tissue flask obtained the best PBMC cultures with a median lymphocyte purity of 88% and a median yield of recovered lymphocytes of 54%. This culture also resulted in the highest proliferation and subsequently the highest stimulation index upon lectin stimulation.  相似文献   
19.
In this study the anti-inflammatory properties of zilpaterol, a beta2-adrenergic receptor (AR) agonist specifically developed as a growth promoter in cattle were investigated. Although zilpaterol has a different structure compared with the beta2-AR agonists known to date, it was noted that it was able to bind to both the beta2-AR (Ki = 1.1 x 10(-6)) and the beta1-AR (Ki = 1.0 x 10(-5)). Using lipopolysaccharide (LPS)-exposed U937 macrophages, the production of cyclic adenosine-3',5'-cyclic monophosphate (cAMP) and tumor necrosis factor alpha (TNF-alpha) were investigated. Zilpaterol inhibited TNF-alpha release and induced intracellular cAMP levels in a dose-dependent manner. The inhibition of TNF-alpha release and induction of cAMP production was mainly mediated via the beta2-AR, as indicated by addition of beta1- and beta2-specific antagonists. The effects of zilpaterol were investigated in LPS-treated male Wistar rats after pretreatment with zilpaterol. Zilpaterol dosed at 500 microg/kg body weight reduced the TNF-alpha plasma levels. In conclusion, zilpaterol is a beta2-adrenergic agonist and an inhibitor of TNF-alpha production induced by LPS both in vivo and in vitro.  相似文献   
20.
A first aim of this batch in vitro experiment (21 h) was to use changes in odd and branched chain fatty acid (OBCFA) patterns to suggest shifts in microbial populations, associated with four types of incubated whole dairy cow diets. Principal component analysis suggested higher dietary starch increased the proportion of C15:0 and C17:0, whereas increased neutral detergent fibre content was positively related to anteiso C15:0 concentrations, which is in agreement with the importance of these fatty acids in respectively amylolytic and cellulolytic bacteria. A second aim of the experiment was to relate rumen volatile fatty acid proportions to OBCFA by principal component regression and to compare these relations with predictions based on diet proximate composition. The R2 values achieved for the regressions between acetate, propionate and butyrate, and OBCFA were 79.6%, 86.6% and 84.9% respectively. Moreover, in the current study, predictions of the rumen fermentation pattern showed higher R2 (p < 0.01) when based on OBCFA compared with proximate feed composition. If relations persist in vivo, there could be scope for milk OBCFA to predict the supply of specific rumen nutrients.  相似文献   
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