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71.
Fifty-one dairy cows were examined three times at weekly intervals during weeks 5 to 7 after calving. Rectal palpation of the ovaries and plasma progesterone assay were used to determine cyclic ovarian function. Eight of 51 cows exhibited true anoestrus by day 49 after calving. Only 23 of 43 cycling cows were served by day 77, the end of the target period for first service. In 77 per cent of 142 examinations, rectal palpation and progesterone assay gave compatible results. Most incompatibility occurred early or late inthe cycle, or in association with cystic structures in the ovaries. Eleven of the 51 cows had cysts in the ovaries but cyclicity and fertility were not adversely affected. 相似文献
72.
A. E. W. Boyd 《Plant pathology》1960,9(3):99-101
73.
74.
A 16-week-old, male boxer dog developed multifocal nodular dermatitis followed by rapidly progressive and fatal neuromuscular disease. Protozoal tachyzoites were demonstrated by aspiration and biopsy of dermal lesions. Necropsy and histology revealed necrotising inflammation associated with intralesional protozoal organisms in various organs including the brain, heart, skeletal muscle and skin. Serology suggested active infection with Neospora caninum. Immunohistochemistry provided a definitive diagnosis. Dermatitis is a finding rarely associated with juvenile neosporosis. The possible role of immunosuppression is discussed. 相似文献
75.
SEASONAL FLUCTUATION IN POTATO SKIN SPOT 总被引:1,自引:1,他引:0
76.
Fertilization and embryonic survival in dairy cattle 总被引:2,自引:0,他引:2
77.
Four cows were inoculated into the uterus with Actinomyces pyogenes between 30 and 41 days of gestation. Gross morphological changes were monitored by rectal palpation and with a realtime B-mode two-dimensional scanner with a 7.5 MHz transrectal linear transducer, shortly before infection and afterwards at three to 12 hours intervals. Two control groups of cows 27 to 50 days pregnant were used: two cows were inoculated with 6 ml of sterile saline into the uterine lumen and four cows were treated with cloprostenol (prostaglandin F2 alpha analogue). There was a change in the uterine fluid from a black, non-echogenic image before infection to a grey or cloudy echogenic image as early as 21 hours after infection. There was an increase in the thickness of the endometrium of the horns and body of the uterus. The embryonic membranes thickened and separated from the endometrium as early as four hours after infection, followed by cessation of the embryonic heart beat, opening of the cervix and abortion. Abortion was followed by an increase in the amount of echogenic intrauterine fluid leading to an increase in the size of the uterus, and the cervix remained open for at least eight days. The area of the corpus luteum remained greater than 2 cm2 throughout the whole period. Intrauterine inoculation with sterile saline had no effects, but the administration of cloprostenol was followed by the death of the embryo and abortion within 72 hours, and the regression of the corpus luteum from greater than 2 cm2 at treatment to 0.4 cm2, 24 hours after abortion.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
78.
An enteric infection in cockatoos associated with a 30 nm diameter enterovirus-like agent seen in faeces and intestinal epithelial cells is described. The disease is characterised by intractable, profuse, mucoid diarrhoea, weight loss, dehydration and death. Lesions in the intestine consist of villous atrophy, villous fusion, enterocyte hyperplasia and, in some cases, chronic inflammation. Affected birds so far examined have concurrent psittacine beak and feather disease. 相似文献
79.
Boyd R 《Science (New York, N.Y.)》2006,314(5805):1555-1556
80.