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231.
The objective of this study was to investigate the development of maternal-filial social attachments between ewes and alien lambs using the technique of "restraint fostering." Forty-eight to 72 h after parturition, 22 Targhee -type ewes were separated from their natural lambs, placed in restraining devices ( stanchions ) and each exposed to a single alien lamb. After a period of 1 or 4 d of restraint, the ewes were subjected to five 10-min lamb acceptance tests over a 48-h period. The observer recorded butts and butt attempts by the ewe and successful and unsuccessful suckle attempts by the lamb. The ewe-lamb pairs were then housed in pens with other groups of ewes and lambs and observed intermittently for acceptance behaviors. Six of the 14 ewes restrained for 4 d and none of the eight ewes restrained for 24 h met the criterion for successful adoption within 48 h. After being housed in group pens, adoptions were achieved by three ewes in the 1-d group and an additional four ewes in the group restrained for 4 d. Ewes restrained for 24 h were significantly more aggressive toward fostered young than ewes restrained for 4 d. In addition, the proportion of successful suckling attempts was significantly lower for lambs fostered on ewes in the 1-d group. Both groups showed a decline in butts and butt attempts over successive acceptance tests, but while the proportion of successful suckling attempts declined for lambs housed with 1-d ewes, they increased over time for lambs fostered on ewes restrained for 4 d.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
232.
A method for the control of ovine footrot is described which utilises the most appropriate measures to suit the circumstances for individual properties. This approach was used to eradicate the disease from three Central Otago fine-wool properties wintering in excess of 35,000 sheep on widely differing classes of land. This programme incorporates the use of proven.techniques and suitable planning together with input from the rural veterinarian, who plays an important role in demonstration and advising on control measures.  相似文献   
233.
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   
234.
The complement fixation test (CFT), the enzyme labelled immunosorbent assay (ELISA) and the gel diffusion precipitin test (GD) were compared, for the diagnosis of Brucella ovis infection in rams. The sensitivities of the tests in 109 rams which were shedding B. ovis in their semen were: CFT 96.3%; ELISA 97.2%; GD 91.7%. The specificities of the tests in 141 rams from non-infected flocks were: CFI 99.3%; ELISA 98.6%; GD 100%. Predictive values of the three tests were measured in 285 rams from infected flocks. Thirty-eight percent of these rams were shedding B. ovis in their semen. Predictive values of positive tests were: CFT 75.5%; ELISA 66.7%; GD 72.5%. Predictive values of negative tests were: CFI 97.1%; ELISA 97.6%; GD 93.8%.  相似文献   
235.
The construction of a simple, portable restrainer for holding sheep in either the horizontal or vertical position for abdominal radiography is described. Examples of its use in locating slow-release pellets-and needles are given.  相似文献   
236.
Pleural effusions can cause dyspnea and cyanosis, and are caused by cardiomyopathy, pyothorax, FIP, FeLV-related disease and trauma. Thoracentesis is used to obtain fluid samples for cytologic examination and culture. Radiographs made after thoracentesis may reveal the cause. Lymphosarcoma causes a sterile exudate containing neoplastic cells. Congestive cardiomyopathy causes a transudate or modified transudate. The sterile exudate of FIP has a proteinaceous background on cytologic examination. The exudate of pyothorax is septic. Treatment depends on the cause but generally includes thoracentesis and supportive care. Cardiomyopathy causes dyspnea, cyanosis, murmurs, gallop rhythms and other arrhythmias. Radiography reveals a globoid heart in the congestive form and a "valentine-shaped" heart in the hypertrophic form. Treatment of congestive cardiomyopathy involves use of furosemide, but is usually unrewarding. Hypertrophic cardiomyopathy is treated with propranolol. Fever may be caused by infection, immune-mediated disease, neoplasia and unknown causes. Treatment is aimed at removal of the underlying cause.  相似文献   
237.
Cysts found in the liver of a horse which had never been out of New Zealand were used to infect two dogs which were slaughtered 35 days after infection. Large numbers of Echinococcus granulosus were recovered. These cestodes were compared with mature dog-sheep cestodes, using light and scanning electron microscopy and identified as the dog-horse strain of E.granulosus.  相似文献   
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