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51.
加拿大安达略省家禽生产者对死禽处理通常有以下几种方法:选择经认证的死畜禽处理公司,坑埋,焚烧,堆肥.本文描述了使用堆肥法成功堆肥家禽屠体的一些关键因素. 堆肥是一个狭长的可被生物降解的有机物质堆,有很大的表面积以便氧气良好地渗透.堆肥通过需氧微生物分解生物有机物质制成一个稳定的、类似土壤的物质,称为腐殖质.为了刺激微生物快速降解,有必要给这些生长增殖的微生物提供最理想的环境. 相似文献
52.
Marcy J. Souza Nancy S. Johnstone-McLean Daniel Ward Kimberly Newkirk† 《Veterinary ophthalmology》2009,12(1):53-55
A 17-year-old female blue and gold macaw ( Ara ararauna ) presented for evaluation of a discreet, conjunctival mass of the OD. No other abnormalities were found on ophthalmic or physical examination. A heterophilic leukocytosis was present on the complete blood count, and elevated aspartate aminotransferase activity, creatinine kinase activity and cholesterol were present on the plasma biochemistry panel. Surgical removal of the mass was complete and no recurrence has occurred by six months after excision. Reduction of dietary fats was recommended to reduce serum cholesterol levels and reduce the likelihood of future occurrence of xanthomas in this bird. 相似文献
53.
Blood samples were taken at weekly intervals from 54 dairy cows (mainly Friesians and Jerseys) during the periods 8 weeks before and 8 weeks after calving. The cows were divided into two age groups; group 1 consisting of 26 cows aged 2 1/2 years and group 2 consisting of 28 cows aged 5–9 years. The changes in the erythrocyte sodium (ENa) and the erythrocyte potassium (EK) concentrations before and after calving were expressed as the slopes for each component regressed on weeks. In the older cows the concentration of ENa decreased (p<0.05) while that of EK increased (p<0.05) after calving. Both the ENa and EK concentrations varied significantly (p<0.01) between cows in the two age groups. The prepartum and postpartum ENa and the postpartum EK concentrations varied significantly (p<0.05) between weeks. EK type did not influence the changes in ENa or EK concentrations before or after calving. 相似文献
54.
R B Brandon M H Gatei H M Naif R C Daniel M F Lavin 《Veterinary immunology and immunopathology》1989,23(1-2):15-27
Haematological parameters and reactivity of lymphocyte antigens to monoclonal antibodies were studied over a 10-month period in sheep experimentally infected with bovine leukaemia virus (BLV). BLV-inoculated animals seroconverted within 1 month and showed a significant lymphocytosis 2-6 weeks after infection. Control animals inoculated with BLV-free lymphocytes showed a stronger and more immediate neutrophil response than those inoculated with BLV-positive lymphocytes. One month after infection, BLV-inoculated sheep showed a relative increase of cells bearing antigens T4, T6, T8 and T19, and 10 months into the trial, MHC II lymphocytes increased, T6 remained elevated, but T4 helper cells were significantly decreased in number. Lymphoma tissue showed the presence of T8 cells, and lymph nodes from seroconverted sheep had areas of concentrated T4 staining cells. These results demonstrate responses in cellular immune mechanisms to infection with BLV. 相似文献
55.
MD Givens MS Marley CA Jones DT Ensley PK Galik Y Zhang KP Riddell KS Joiner BW Brodersen SP Rodning 《Journal of the American Veterinary Medical Association》2012,241(4):484-495
Objective-To determine whether administration of 2 doses of a multivalent, modified-live virus vaccine prior to breeding of heifers would provide protection against abortion and fetal infection following exposure of pregnant heifers to cattle persistently infected (PI) with bovine viral diarrhea virus (BVDV) and cattle with acute bovine herpesvirus 1 (BHV1) infection. Design-Randomized controlled clinical trial. Animals-33 crossbred beef heifers, 3 steers, 6 bulls, and 25 calves. Procedures-20 of 22 vaccinated and 10 of 11 unvaccinated heifers became pregnant and were commingled with 3 steers PI with BVDV type 1a, 1b, or 2 for 56 days beginning 102 days after the second vaccination (administered 30 days after the first vaccination). Eighty days following removal of BVDV-PI steers, heifers were commingled with 3 bulls with acute BHV1 infection for 14 days. Results-After BVDV exposure, 1 fetus (not evaluated) was aborted by a vaccinated heifer; BVDV was detected in 0 of 19 calves from vaccinated heifers and in all 4 fetuses (aborted after BHV1 exposure) and 6 calves from unvaccinated heifers. Bovine herpesvirus 1 was not detected in any fetus or calf and associated fetal membranes in either treatment group. Vaccinated heifers had longer gestation periods and calves with greater birth weights, weaning weights, average daily gains, and market value at weaning, compared with those for calves born to unvaccinated heifers. Conclusions and Clinical Relevance-Prebreeding administration of a modified-live virus vaccine to heifers resulted in fewer abortions and BVDV-PI offspring and improved growth and increased market value of weaned calves. 相似文献
56.
Soares Camila Rocha Júnior Vicente Ribeiro Monção Flávio Pinto Borges Lucas Daniel Alcântara Caldeira Luciana Albuquerque Costa Natanael Mendes Ruas José Reinaldo Mendes Rigueira João Paulo Sampaio da Cunha Siqueira Carvalho Cinara de Sales Eleuza Clarete Junqueira de Assis Pires Daniel Ananias Chamone Julieta Maria Alencar 《Tropical animal health and production》2020,52(5):2567-2576
Tropical Animal Health and Production - The qualities of food, mainly of animal origin, have always been of concern to consumers. It is known that the composition of animals’ diets can... 相似文献
57.
<正>嗅觉是动物最原始的感觉,现代人类的嗅觉越来越差,但对于绝大多数动物来说,嗅觉仍是高度发达的感觉器官,是其生存必不可少的一部分。嗅觉可给动物预警,帮助动物寻找食物,从营养物中分辨出有毒食物等。嗅觉也参与繁殖(从交配到辨认自己的幼仔)。牛和猪都有非常敏感的 相似文献
58.
Daniel A. Heinrich Anne C. Avery Michael S. Henson Jed A. Overmann Aaron K. Rendahl Jillian Z. Walz Davis M. Seelig 《Veterinary and comparative oncology》2019,17(3):365-375
Minimally invasive techniques used to evaluate canine peripheral lymphadenopathy (PLN), including fine needle aspiration biopsy with cytological evaluation (FNAB‐C) and flow cytometry (FC), have benefits and limitations. The cell block (CB) method is an alternate processing technique in which fine needle aspirate biopsy samples are concentrated, fixed, and embedded in paraffin for routine histological processing/staining. Utilizing three observers, we determined the diagnostic value of the CB in evaluating canine PLN across six categories (non‐diagnostic, reactive, inflammatory/infectious, probable lymphoma and lymphoma, metastatic neoplasia) and correlated findings to immunophenotypic and clonal antigen receptor rearrangement results in canine nodal lymphoma. Eighty‐five paired FNAB‐C and CB samples were evaluated from canine patients presenting to the University of Minnesota Veterinary Oncology or Internal Medicine services. Diagnostic quality samples were obtained in 55/85 (65%) CB and 81/85 (95%) FNAB‐C samples, respectively, and nodal pathology impacted CB diagnostic yield. Overall percent agreement between diagnostic‐quality FNAB‐C and CB samples was 86%, but increased to 95% if the categories of lymphoma and probable lymphoma were combined. There was 100% agreement for both the diagnoses of metastatic neoplasia and reactive lymph nodes and 92% agreement for the diagnosis of lymphoma/probable lymphoma. Using immunohistochemistry (IHC), CB samples correctly immunophenotyped 22/23 (96%) cases of B‐cell lymphoma, but only 1/6 (17%) cases of T‐cell lymphoma. IHC was not completed on nine cases of lymphoproliferative disease because of insufficient cellularity. When the CB method (CBM) yielded diagnostic quality samples there was good to excellent agreement with FNAB‐C samples and CB samples were suitable for some IHC tests. 相似文献
59.
Rose L. Cherry Kryssa L. Johnson Adrien‐Maxence Hespel Karen M. Tobias Daniel A. Ward 《Veterinary ophthalmology》2019,22(3):353-359
A 2‐year‐old, male castrated German shepherd dog was presented to the University of Tennessee Veterinary Medical Center (UTVMC) with periorbital swelling and conjunctival mucopurulent discharge 2 days following removal of a twig from the medial canthus by the owner. Diagnostic imaging was pursued due to the suspicion of a retrobulbar foreign body (FB). A cylindrical FB approximately 3.0 cm in length and 1.0 cm in diameter with concentric rings, suspected to be wooden material, was identified on computed tomography (CT) imaging. An attempt to remove the FB via a stab incision using ultrasound guidance was unsuccessful, and postmanipulation ultrasound confirmed the FB position was unchanged. An exploratory orbitotomy was performed, using the acquired CT images for guidance in locating the FB; however, the FB was not present at the predicted site. The CT imaging was repeated and showed that the FB had migrated rostrally approximately 3.0 cm, compared to the originally acquired study and its same location during attempted ultrasound‐guided removal. A combination of CT‐guided needle placement and contrast injection was then used with repeat imaging in an attempt to better localize the FB and its soft tissue tract. The dog was taken back into the operating room, and the wooden FB was successfully removed. 相似文献
60.
OBJECTIVE: To determine the effects of endotoxin administration on thyroid function test results and serum tumor necrosis factor-alpha (TNF-alpha) activity in healthy dogs. ANIMALS: 6 healthy adult male dogs. PROCEDURES: Serum concentrations of thyroxine (T4), 3,5,3'-triiodothyronine (T3), 3,3'5'-triiodothyronine (rT3), free T4 (fT4), and endogenous canine thyroid stimulating hormone (TSH), and TNF-alpha activity were measured before (day-1; baseline), during (days 0 to 3), and after (days 4 to 24) IV administration of endotoxin every 12 hours for 84 hours. RESULTS: Compared with baseline values, serum T3 concentration decreased significantly, whereas rT3 concentration increased significantly 8 hours after initial endotoxin administration. Serum T4 concentration decreased significantly at 8 and 12 hours after initiating endotoxin administration. Serum T4 concentration returned to reference range limits, then decreased significantly on days 6 to 12 and 16 to 20. Serum fT4 concentration increased significantly at 12, 24, and 48 hours after cessation of endotoxin treatment, compared with baseline values. Serum rT3 concentration returned to reference range, then decreased significantly days 5 and 7 after stopping endotoxin treatment. Serum TNF-alpha activity was significantly increased only 4 hours after initial endotoxin treatment, compared with baseline activity. CONCLUSIONS AND CLINICAL RELEVANCE: Endotoxin administration modeled alterations in thyroid function test results found in dogs with spontaneous nonthyroidal illness syndrome. A decrease in serum T4 andT3 concentrations and increase in serum rT3 concentration indicate impaired secretion and metabolism of thyroid hormones. The persistent decrease in serum T4 concentration indicates that caution should be used in interpreting serum T4 concentrations after resolution of an illness in dogs. 相似文献