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991.
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
992.
Papovavirus induced feather abnormalities and skin lesions in the budgerigar: clinical and pathological findings 总被引:3,自引:2,他引:1 下载免费PDF全文
Bernier G Morin M Marsolais G 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(8):307-310
Feather abnormalities and skin lesions caused by a papovavirus infection in budgerigars are described. Diseased one to 15 day old birds displayed a lack of nestling down feathers and filoplumes on the head and neck. Survivors older than 15 days exhibited retarded growth and temporary absence of feathers variable from bird to bird. Several birds between 15 and 25 days of age had flight feathers with total absence or marked sparseness of the vanes. After 25 days, feathers began to grow, although the tail and/or some flight feathers of some of the birds remained underdeveloped or absent for several weeks. Several of these affected birds were unable to fly and are called “runners”
Microscopic lesions in the feather follicles of the affected birds less than 15 days of age, were characterized by focal, multifocal or diffuse ballooning degeneration in the lateral and axial plate cells of the barb ridges with the presence of large basophilic or amphophilic intranuclear inclusions in the same cells. Focal areas of ballooning degeneration with intranuclear inclusions were also found in the epidermis. Clinical observations made on these birds are compared with those reported in the literature for French molt.
相似文献993.
A stranded young pygmy sperm whale was nursed for four days in a pool, fed an artificial diet via a stomach tube and injected intramuscularly with antibiotics and corticosteroids. Initially unable to maintain her balance or to swim, she showed progressive improvement and by the third day could swim and dive quite strongly. Early on the fifth day her condition rapidly worsened and she died. An autopsy revealed extensive deep bruising in the head and mid-abdominal regions consistent with injuries sustained during the stranding. 相似文献
994.
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
995.
The serological identity of 234 strains of Yersinia pseudotuberculosis recovered from domestic animals and birds in New Zealand was determined by slide agglutination test. Thirty strains were also examined by tube agglutination test. The strains were isolated from cattle (56), sheep (8), deer (117), goats (13), pigs (7), rabbits (6), guinea pigs (5), and aviary species of birds (22). All strains were isolated from animals or birds which had died or shown signs of ill health and amongst which diarrhoea was a common feature. Serotype I accounted for 23% (53) of strains, serotype II for 13% (30) of strains and serotype III for 64% (151) of strains. It was concluded that further investigations on the prevalence and serological identity of strains recovered from clinically healthy animals mav provide useful information in assessing the significance of various serotypes as a cause of disease in livestock. 相似文献
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Specificities of antinuclear antibodies detected in dogs with systemic lupus erythematosus 总被引:4,自引:0,他引:4
O Costa C Fournel E Lotchouang J C Monier M Fontaine 《Veterinary immunology and immunopathology》1984,7(3-4):369-382
Five hundred and eighty dogs with at least one clinical sign compatible with a systemic lupus erythematosus (SLE) were entered in a prospective study aimed at evaluating the prevalence of antinuclear antibodies (ANAb). SLE was diagnosed in 38 of these dogs (group A) which fulfilled at least four American Rheumatism Association (ARA) criteria; of these, sixteen had ANAb titers greater than or equal to 4096. The 23 dogs which met three or two ARA criteria (group B) had an ANAb geometric mean titer (GMT) of 259. Dogs (group C) with only 1 criterium had an ANAb GMT of 75. Anti-ds-DNA Ab were present in 6 dogs from group A (16%), and 2 dogs from group B (9%). Anti-histone Ab were present among dogs from group A, B and C with frequencies of 81%, 67% and 26%, respectively. Among dogs from group A, the ANAb titers and the levels of anti-histone Ab correlated positively when individual sera were considered. Antibodies against the soluble nuclear antigen (SNA) were detected in 74%, 39% and 13% of the dogs from groups A, B and C, respectively. Antibodies initially described in human SLE also exist in SLE dogs. Anti-Sm Ab were found in 24% of dogs in group A. With anti-RNP Ab the frequency was still lower (10%). However, two other types of anti-SNA Ab against RNAse and trypsin-resistant antigens, not found in human "reference sera", were often detected. The first type (anti-type 1 Ab) was found in 26% and 9% of group A and group B, The first type (anti-type 1 Ab) was found in 26% and 9% of group A and group B, respectively; the second type (anti-type 2 Ab) is less frequent, and was found in 13% and 17% of group A and B, respectively. It appears that testing for anti-Sm, anti-type 1 and anti-histone Ab should be performed in order to improve the diagnosis of SLE in dogs. 相似文献