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141.
Objective To determine whether dogs and cats are potential reservoirs of Ross River (RR) and Barmah Forest (BF) viruses
Method Young seronegative female dogs and cats were experimentally exposed to the viruses using Ochlerotatus vigilax (Skuse) mosquitoes.
Results Only one of the 10 dogs and one of the 10 cats exposed to RR developed neutralising antibody. None of the animals developed detectable viraemia or clinical signs. One dog and three cats exposed to BF developed neutralising antibody. In addition, a serological survey of sera obtained from domestic dogs and cats residing in the Brisbane region indicated that 23.7% and 1.3% of dogs, and 14% and 2% of cats, had neutralising antibodies to RR and BF respectively.
Conclusions Although dogs and cats are exposed naturally to these viruses, and can become infected, they are unlikely to be important urban reservoirs of either virus.  相似文献   
142.
Studies of enteric coronaviruses in a feline cell line   总被引:1,自引:0,他引:1  
Development is reported of a feline cell line which can support the growth of coronaviruses from canine (CCV), feline (FIPV) and porcine (TGEV) species. The cell culture has been serially transferred over 100 times and has retained its initial growth requirements, proliferative capacity and morphologic features. Each virus had specific growth characteristics in this cell culture although all produced a similar CPE and plaques under agar. Cross neutralization studies demonstrated a two-way relationship between TGEV and CCV and between TGEV and FIPV, whereas a one-way relationship was demonstrated between CCV and FIPV.  相似文献   
143.
Fifteen steers were vaccinated after shipment with a modified live virus vaccine containing infectious bovine rhinotracheitis (IBR), bovine virus diarrhea (BVD), and bovine myxovirus parainfluenza-3 (PI3), and 16 unvaccinated steers were kept as controls. Geometric mean titers one month after vaccination were highest to BVD, followed by PI3 and IBR. Weight gains were higher during 30 days after vaccination in the controls. One case of acute respiratory disease developed in one vaccinated calf. Revaccination 79 days after the first dose increased antibody to PI3 and BVD virus but not IBR. In a second trial, no clinical respiratory disease developed after shipment of 13 heifers that received an antibacterial-antiviral antiserum or in the 12 controls. Weight gains 30 days after shipment were identical in both groups.  相似文献   
144.
Chronic hepatic insufficiency due to anomalies of the portal venous system was diagnosed in 6 young dogs. The disorder was characterized by a variety of abnormal central nervous system signs or ascites, or both. Laboratory findings were characteristic of chronic, generalized hepatic dysfunction. The diagnosis was established by angiographic studies of the portal venous system. Of the 6 dogs, 3 died, 1 was euthanatized, and 2 are still alive and require medical management for ascites.  相似文献   
145.
Serum samples from 458 swine from eight specific pathogen-free (SPF) herds swine were compared to samples from 178 swine from eight non-SPF herds in Illinois using the complement fixation (CF) test for Mycoplasma hyopneumoniae antibodies. In SPF herds, 9.4% of the samples gave positive test results, compared to 51.7% of the samples from non-SPF herds. The range of reactor rates in SPF herds was 0–26.9% and in non-SPF herds 3.4–100%. Used on herd basis with some modification, the CF test should be useful in monitoring state and nationally accredited SPF swine herds.  相似文献   
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During the fall of 1969, 1970 and 1971, Central Illinois practitioners preconditioned (PC) 1,576 beef calves at a cost range of $3.02 to $4.72. The PC program included weaning calves 30 days before sale, having calves eating grain from a bunk and drinking from a tank, vaccinated against blackleg, malignant edema, infectious bovine rhinotracheitis (IBR) and bovine parainfluenza virus (PI3). Calves were tagged in the right ear with the green certified preconditioned for health (CPH) tag of the American Association of Bovine Practitioners. Bovine virus diarrhea (BVD) vaccine was added to the program in 1970 and 1971 since clinical cases of the disease occurred in PC calves not receiving the vaccine in 1969. Intranasal PI3 vaccine and Pasteurella hemolytica and multocida bacterin was added to the 1971 program to attempt better immunization. In 1969, more PC than non-preconditioned (NPC) calves were treated for acute respiratory disease after sale. The 1970 study showed that fewer PC than NPC calves were treated for acute respiratory tract disease. The 1971 finding showed the greatest differences. A comparison of 389 PC and 227 NPC calves sold at auction in 1971 and moved into the same feedlots showed a statistically significant reduction in number of cases of acute respiratory tract disease treated in PC calves. Generally, PC calves sold at a higher price than NPC calves.  相似文献   
150.
A 23-year-old Quarter Horse gelding was admitted to the hospital because of cachexia and hyperactive behavior of 1 year's duration. At admission the horse was severely emaciated, tachycardic with a grade V/VI diastolic murmur, pyrexic, polydipsic, enophthalmic, and alopecic. The right lobe of the thyroid gland was noticeably larger than typical. The horse was also hyperexcitable and had a ravenous appetite. A presumptive diagnosis of hyperthyroidism was made on the basis of clinical signs and high plasma thyroid hormone concentrations. Confirmation of the diagnosis was made on the basis of results of a triiodothyronine-suppression test. Following endocrine testing, the affected portion of the thyroid gland was removed and identified histologically as an adenoma. Return or plasma thyroid hormone concentrations to reference range values and resolution of the clinical signs of disease following hemithyroidectomy provided further conformation of the diagnosis. On the basis of finding in this horse, it appears that horses with hyperthyroidism may be successfully treated by hemithyroidectomy.  相似文献   
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