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81.
Social genetic relationships among average daily gain (ADG, g) and feeding pattern as daily feed intake (DFI, g), daily feeder occupation time (DOT, min), and daily feeding rate (DFR, g/min) were examined using records of 547 Duroc boars. Single‐trait animal models were fitted differently for traits, including or excluding social genetic effects, random or fixed pen effects, with covariates of pen sizes and initial age or weight. Genetic parameters for feeding pattern were estimated by restricted maximum likelihood. Six sets of parameters for ADG based on literature estimates were used due to difficulty in untangling confounded effects. Positive and negative signs of direct‐social genetic covariances were interpreted as heritable cooperation and competition, respectively. Dominant and subordinate pigs were classified as pigs with higher direct and social genetic values, respectively. Correlations of estimated breeding values between ADG and DFI, DOT, and DFR were 0.46, 0.04 and 0.29 for dominant pigs. Given heritable cooperation, subordinate pigs tended to increase feed intake (r = 0.36) and eating rate (r = 0.25). Given heritable competition, subordinate pigs fail to compensate for the competition with decreased feed intake (r = ?0.53). The slow eating rate (r = ?0.31) was considered as a consequence of eating during less busy hour of feeding.  相似文献   
82.
A scheme to control and eradicate bovine virus diarrhoea (BVD) was initiated in 1994 in the Shetland Islands by local veterinary surgeons and funded by the Shetland Islands Council and Shetland Enterprise Company. Over a 3-year period every bovine animal on the islands was blood-sampled (heparinised) and laboratory tested using MAb-based ELISAs for BVD virus antibody and antigen detection for evidence of disease. A number of BVD virus positive animals (40) were found and culled. A total of 6150 animals were tested from 213 herds and 43% herds were found to be BVD naive. The remaining herds had experienced infection and contained many BVD antibody positive animals. Some repeat sampling of stock in infected herds determined further virus positive animals which were slaughtered and in 1997 the scheme ceased since it appeared that there were no persistent excretors present. The major risk to the Shetland Islands is from bought-in stock, especially animals which are imported in calf. It is vital that all bought-in animals are tested and proven to be free of BVD virus if these animals are in calf, the calves must be tested a birth to determine status. It is strongly advised that only bulls and bulling heifers or cows are bought into Shetland in future, thus, protecting the present stock. Continued surveillance will be required to claim eradication of BVD from Shetland.  相似文献   
83.
The serological response of naturally and experimentally infected lambs to orf virus infection was analysed using an enzyme-linked immunosorbent assay (ELISA) together with the Western blotting technique. The combination of these two methods permitted a qualitative and quantitative assessment of the response, which revealed considerable variation between animals. Despite this, all post-exposure sera reacted with a polypeptide (molecular weight 40 kilodaltons) which appears to be a component of the surface tubules that are characteristic of the virus.  相似文献   
84.
A 14-year-old, female spayed Domestic Short-haired cat was presented for evaluation of progressive superficial corneal ulceration with mucoid ocular discharge, blepharospasm, and conjunctival hyperemia OD. Upon examination, ulcerative keratitis with stromal loss, chemosis, corneal edema, miosis, aqueous flare, and hyphema were noted. Corneal cytology revealed branching, septate fungal hyphae with bulbous terminations and associated ovoid structures, with suppurative inflammation. Fungal culture of corneal swabs confirmed the presence of Acremonium, although PCR of the cytology sample was negative. Ten days of treatment with topical 1% miconazole resulted in clinical deterioration before switching to topical 1% voriconazole solution, which was successful in resolving the infection. The apparent clinical efficacy of the topical antifungals used contrasted with the in vitro susceptibility profile.  相似文献   
85.
86.
A well-designed and executed diagnostic approach to patients with bleeding disorders is critical to determine disease etiology and guide therapeutic measures. This systematic process begins with a comprehensive history and physical examination, followed by laboratory tests of primary hemostasis (platelet enumeration, platelet function testing, and von Willebrand factor assays), secondary hemostasis (prothrombin time, activated partial thromboplastin time, activated clotting time, and individual factor deficiencies), and fibrinolysis (fibrinogen activity, thrombin time, fibrin degradation products, D-dimers), dependent on the clinical picture. Equally valuable are proper specimen collection, handling, and storage methods, which provide reliable and reproducible result interpretation. This review will emphasize the common diagnostic tools and blood sampling techniques important to the workup of hemostatic diseases as well as provide an overview of advanced clinical and research methods and equipment available to assist our bleeding veterinary patients, including thromboelastography/thromboelastometry, calibrated automated thrombogram, and the thrombin-antithrombin assay.  相似文献   
87.
88.
Premature parturition was successfully induced with a preparation containing 2 dexamethasone esters in 709 out of 716 cows and heifers of gestational periods ranging from 3 to 8 months. A mortality rate of 38.5% was experienced among calves produced by induced cows, while only a 2.7% mortality rate occurred among 4,330 calves from normal parturitions. Approximately 50% of all treated cattle retained foetal membranes, but with apparently no ill-effect. The treatment apparently did not affect milk production, post-calving fertility, and the overall incidence of dystocias in cows and post-calving diseases. Three deaths occurred among induced cattle, but they could not be attributed to the treatment. It was concluded that the technique may prove to be of great value in dairy cattle, in seasonal milking areas.  相似文献   
89.
Anabolic steroid implants are routinely used to increase growth performance and profitability; however, there are concerns that the use of implants, particularly those containing trenbolone acetate, may have detrimental effects on carcass quality and beef tenderness. Thus, the objectives of the current study were to determine the effects of various commonly used implant regimens on shear force values, sensory properties, and consumer satisfaction of beef top loin steaks from cattle of Bos indicus influence. Cattle were supplied by producers that agreed to provide sire and dam information in exchange for carcass and sensory data. Steers (n = 2,748) were assigned randomly to one of three implant treatments (12/sire; four steers from each sire were placed into each treatment group): 1) unimplanted controls (n = 1,368); 2) Synovex-S followed by another Synovex-S (n = 660); or 3) Synovex-S followed by Revalor-S (n = 720). Steaks sampled after 3, 7, and 14 d of aging indicated that unimplanted cattle had lower (P < 0.05) Warner-Bratzler Shear force values than those from implanted animals. No differences (P > 0.05) in shear force values were found between the two treatments or the control groups for steaks sampled following a 21-d aging period. Steaks from implanted animals sampled after 3, 7, and 14 d aging were rated lower (P < 0.05) for initial and sustained trained sensory panel tenderness scores. Consumers failed to detect any differences in steak samples related to implant treatment after 7 and 14 d of aging. Consumer education level and family income did not affect overall acceptability (P > 0.10 and 0.18, respectively) or tenderness acceptability (P > 0.11 and 0.68, respectively); however, consumers with postgraduate degrees recorded lower (P < 0.05) overall quality, beef flavor, juiciness, and tenderness scores than consumers in all other education classifications. Additionally, family income had no effect on overall quality (P > 0.21), beef flavor (P > 0.28), juiciness (P > 0.58), or tenderness (P > 0.45) scores. Results indicate that using a moderate implant program in Bos indicus-influenced cattle has no detrimental effects on beef tenderness and consumer acceptability.  相似文献   
90.
OBJECTIVE: To determine clinical features, diagnostic imaging abnormalities, underlying disease, disease progression, and outcome in dogs with bilateral cavernous sinus syndrome. DESIGN: Retrospective study. ANIMALS: 6 dogs. PROCEDURE: Dogs were included if clinical signs consistent with bilateral cavernous sinus syndrome (i.e., deficits of the third, fourth, and sixth cranial nerves and at least 1 of the first 2 branches of the fifth cranial nerve) were present and a lesion of the cavernous sinus was identified by means of diagnostic imaging or postmortem examination. RESULTS: 5 dogs were evaluated because of problems referable to abnormal ocular motility or pupillomotor dysfunction, and 1 dog was evaluated because of partial motor seizures involving the face and bilateral mydriasis. Four dogs had neurologic signs referable to an extrasinusoidal lesion at the time of initial examination, and the remaining 2 dogs eventually developed extrasinusoidal signs. Besides neuroanatomic location, the only consistent neuroimaging feature was variably intense, heterogeneous enhancement of cavernous sinus lesions. Neoplasia was histologically confirmed as the underlying cause in 5 of the dogs and was suspected in the remaining dog. Median survival time for the 4 dogs that were treated was 199 days (range, 16 to 392 days). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that bilateral cavernous sinus syndrome is rare in dogs but should be suspected in dogs with compatible clinical signs. Affected dogs have a poor prognosis, and dogs with clinical signs of bilateral cavernous sinus syndrome should be systematically evaluated for neoplastic disease.  相似文献   
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