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991.
A strategy for control of bovine leukemia virus infection: test and corrective management 总被引:2,自引:2,他引:0 下载免费PDF全文
Ruppanner R Behymer DE Paul S Miller JM Theilen GH 《The Canadian veterinary journal. La revue veterinaire canadienne》1983,24(6):192-195
Test and corrective management was applied in one dairy herd (130 milking cows) to control bovine leukemia virus infection. It consisted of: raising uninfected calves in order to establish a pool of uninfected replacement heifers, preventing transmission of bovine leukemia virus through transfer of blood from animal to animal and closing the herd. Regular herd testing was combined with selected changes in herd management. These procedures have been followed since January 1979. Prevalence of antibodies (as determined by gel-immunodiffusion) has declined markedly since the program was implemented. 相似文献
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993.
The duration of immunity to an inactivated adjuvanted canine parvovirus vaccine. A 52 and 64 week postvaccination challenge study 总被引:1,自引:1,他引:0 下载免费PDF全文
Povey RC Carman PS Ewert E 《The Canadian veterinary journal. La revue veterinaire canadienne》1983,24(8):245-248
Dogs were successfully isolated for a period of either 52 or 64 weeks following vaccination with an inactivated, adjuvanted canine parvovirus-2 vaccine. Antibody persisted in all ten vaccinated dogs, although in one case by 52 weeks postvaccination only virus neutralizing antibody, and not hemagglutination-inhibiting antibody, could be detected. Sentinel unvaccinated dogs housed alongside the vaccinated dogs throughout the study remained free of canine parvovirus-2 antibody until challenged. Upon oral challenge with canine parvovirus-2 infected material all unvaccinated dogs developed one or more signs of canine parvovirus-2 disease, shed virus and developed antibody. None of the vaccinated dogs became overtly sick. Of the five vaccinated dogs challenged 52 weeks after vaccination, three shed virus and one showed a significant rise in antibody. At 64 weeks after vaccination only one of the five challenged dogs shed virus and showed a boost in antibody titer. 相似文献
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997.
Lavigne C Smith HJ 《The Canadian veterinary journal. La revue veterinaire canadienne》1983,24(12):389-390,391
In 1982, approximately 13,000 Canadian cattle were treated once for sarcoptic mange with ivermectin at a dose of 10 mg per 45.4 kg of body weight. The results showed 100% efficacy against Sarcoptes scabiei and other ectoparasites present. All cattle showed marked improvement in general condition with new hair growth and apparent weight gains by 31 days posttreatment. Surveillance of treated herds for a year following treatment showed that one parenteral treatment with ivermectin eradicated the disease from closed herds. 相似文献
998.
A condition resembling chronic malignant catarrhal fever was seen in a 9-month-old pet sika hind (Cervus nippon). From an initial acute depression, pyrexia, and anorexia, the condition progressed to include hypopyon, keratitis, lethargy, loss of condition, sloughing of one hoof and eventually death after seven weeks. There were multiple, 5 to 8mm diameter dark-red nodules throughout the mesenteries and mediastinum, along abdominal organ ligaments, and about the uterus and kidneys. Histopathology showed the nodules to be organising vascular thrombi. Concurrent perivascular mononuclear infiltrations and intravascular thrombi in many tissues confirmed that the condition was malignant catarrhal fever. 相似文献
999.
Blackmore DK 《New Zealand veterinary journal》1983,31(10):167-169
1000.
Ross AD 《New Zealand veterinary journal》1983,31(10):170-172
Changes in formalin concentration were measured over time in uncontaminated solutions and solutions heavily contaminated by mud, faeces, wool or straw. Shallow plastic trays containing 1.11 of a 9% aqueous solution of formalin were exposed for 6 days (trial 1) or 8 days (trial 2) to windy autumn weather. Evaporation of solution volumes was high (47-73%). Concentration generally increased over time: by 13-31% in trial 1 and by 61-162% in trial 2. These figures represent actual increases in percentage formalin of up to 3.0% in trial 1 and up to 7.6% in trial 2. Exposure to mud, sheep faeces or wool did not affect the increase in concentration but there was no increase in the presence of straw. As exposure to excessively concentrated formalin solutions produces hyperaemia, cracking of interdigital skin and lameness in sheep it is recommended that footbath solutions should be diluted to 2-S%, prepared on the day of use and discarded daily whether contaminated or not. Addition of formalin or water to existing solutions of unknown strength should be avoided. 相似文献