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1.
福建黄兔繁殖性状相关研究 总被引:5,自引:0,他引:5
本文对310只母兔的繁殖性状进行了测定分析,结果表明;妊娠期与产仔数、产活仔数及活仔窝重呈负相关,相关系数分别为-0.426*、-0.350*和-0.515头4胎内母兔,胎次对产仔性能无影响,对母兔泌乳性能有一定影响。同样条件下胎次增加。泌乳性能提高,第3胎较第2胎有显著提高。 相似文献
2.
本文对光箨篌竹笋期的出笋规律、成竹规律以及竹笋的生长发育规律进行了研究。初步认为,光箨篌竹林分的母竹立竹度一般应保持在2500株/亩左右、Ⅰ~Ⅱ级母竹株数保持在40%以上时,才能保证林分的优质高产与稳产;抽枝成竹历期长短受竹笋笋级大小、出土早晚或立地环境条件的影响可相应延长或推迟2~4d左右,一般历时25d,竹笋开始抽枝成竹时的高度一般为5m左右;竹笋在生长发育高峰期明显受到气候因子的影响,尤其是对气温更为敏感。 相似文献
3.
Dominique G. Penninck DVM Antony S. Moore BVSc MVSc Amy S. Tidwell DVM Michael E. Matz DVM Greg O. Freden DVM 《Veterinary radiology & ultrasound》1994,35(4):299-306
Clinical, radiological and ultrasonographic findings from 22 cats with gastrointestinal lymphosarcoma were reviewed. The most common clinical findings were anorexia, weight loss, vomiting, lethargy, depression, fever, anemia and a palpable abdominal mass. Abdominal radiographs of 12 cats revealed a mass associated with the gastrointestinal tract and/or mesentery, and decreased serosal detail, suggestive of peritoneal effusion. The most common ultrasonographic finding was transmural gastric or intestinal thickening associated with loss of normal wall layering, reduced wall echogenicity and localized hypomotility. As is noted in people, other patterns such as transmural-segmental, transmural-nodular, transmural-bulky and mucosal infiltration were represented. In 3 cats, mesenteric lymph-adenopathy was responsible for most of the mass-effect. Fine-needle aspiration biopsy, automated microcore biopsy, endoscopic biopsy or necropsy confirmed the diagnosis of lymphosarcoma in all cats. Chemotherapy was instituted in 19 cats. Only 6 cats had a complete response to treatment. The results of this study indicate that ultrasonography is a valuable tool for the diagnosis of feline alimentary lymphosarcoma and that biopsies can be obtained under ultrasonographic guidance. 相似文献
4.
Amy M Grooters Joseph Taboada 《Veterinary Clinics of North America: Small Animal Practice》2003,33(4):749-58, vi
Fungal pathogens are becoming increasingly important for human and small animal medicine. This article highlights many standards-of-care and new agents for treatment of these pathogens for small animals and people. 相似文献
5.
An enzyme-linked immunospecific assay (ELISA) for the serodiagnosis of Brucella ovis infection in sheep is described and compared with the cold complement fixation (CF) test. ELISA was performed in microtiter plates, using horse-radish peroxidase conjugated to anti-normal sheep serum globulins, and hydrogen peroxide plus o-phenylenediamine as substrate. A heated, cell-free B. ovis extract was used as antigen in both tests. ELISA was easier to perform, distinguished better between positive and negative sera, and did not need heat-inactivated sera. 相似文献
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Amy Wells Karen A Terio Michael H Ziccardi Linda Munson 《Journal of zoo and wildlife medicine》2004,35(1):8-14
The captive North American cheetah (Acinonyx jubatus) population is not self-sustaining because of high prevalences of unusual diseases and poor reproductive success. Cheetahs are commonly moved between zoos for breeding purposes to maintain genetic diversity within the captive population, and movement may exacerbate infertility and disease. Fecal corticoids were analyzed by radioimmunoassay to measure the stress response of cheetahs to movement between facilities. Fecal samples were collected from 15 cheetahs for 14 days before movement and for at least 30 days after movement. For each cheetah, premovement fecal corticoid concentrations were used to determine baseline and then compared with trends in postmovement concentrations. In general, postmovement corticoid concentrations either increased (n = 8), did not change (n = 2), or decreased (n = 5). Although individual animal differences occurred, corticoid concentrations increased for most animals moved on-exhibit and decreased in animals moved off-exhibit. Animals moving on-exhibit had an 18-times greater risk of having corticoids elevated more than two standard deviations above baseline for 30 days after movement compared with animals that moved off-exhibit. In addition, greater day-to-day variation in corticoids occurred in animals moved on-exhibit. In general, animals with initially low baseline corticoid concentrations had a greater postmovement corticoid response than cheetahs with initially high baseline levels. These results indicate that some cheetahs have a prolonged stress response when moved between facilities, and the magnitude and character of this response is influenced by the exhibit environment. 相似文献
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宁南山区旱地紫花苜蓿土壤水分及产量动态研究 总被引:19,自引:0,他引:19
对宁南山区旱地紫花苜蓿土壤水分及产量动态进行了研究。结果表明,随苜蓿草龄的延长,土壤深层水分亏缺严重草地底层与中层对表层水分具有明显的补偿作用;伏秋降对水冬前土壤蓄水亦有重要作用;产量随草延长呈中间高两头低的态热,6-8年以后草地须及时更新。 相似文献