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1.
Goats from 28 states were tested for antibodies to caprine arthritis-encephalitis virus. Of 3,790 goats, 1,175 (31%) tested positive, and of 196 herds tested, 143 (73%) had 1 or more seropositive members. This prevalence, based on serum samples from all goats in the participating herds, was lower than most rates reported in other studies. Such studies were based on fewer samples, incomplete sampling of herds, or smaller geographic base. Prevalence was highest in western Pacific and northern plains regions, increased with age to 3 years, was highest among goats on family-owned farms, and was lowest in the Angora breed. Differences in prevalence was not related to gender or size of herd.  相似文献   
2.
A bovine adenovirus with agglutinating activity was isolated from feedlot calves and classified as serotype 3. The agglutinating activity was shown to be the property of an adenovirus-associated virus (AAV). The AAV was isolated from the bovine adenovirus by isopycnic centrifugation in CsCl; the AAV had a density of 1.4 g/cm2. This AAV is serologically related to bovine AAV-TR-15, but is distinct from bovine parvovirus-1 and primate AAV types 1 to 4, using counterimmunoelectrophoresis and hemagglutination-inhibition.  相似文献   
3.
The practice of horse rugging has important implications for horse welfare and performance, but in Australia, rugging practices have not been properly documented. The objective of this study was to obtain an understanding of Australian horse rugging practices. An online survey reviewed the management of 2659 Australian horses over 12 months. Of the reported horses a total of 84.8% were rugged, although most owners (69.5%) indicated that they were unsure whether horses needed to be rugged at all. Rugging was felt by 59.8% of owners to be a requirement for horses in competition. Riding and competition were significantly associated with the use of rugs. Nearly all respondents (89.0%) felt that ‘over-rugging’ was a concern. However, 4.8% of owners would use up to 4 rugs at any one time on their horse and 21.4% of horses were still rugged in temperatures above 20°C in Australia. Many Australian horse owners (42.8%) also believe that horses feel cold if they are not rugged. Anthropomorphism when it comes to rugging horses cannot be justified as the horse has a much wider thermoneutral zone (TNZ) than humans. Australian climate, owner opinions, equestrian discipline and whether a horse is used for riding influence Australian horse rugging practices. However, current practices are based on limited available research and are not necessarily to the benefit of the horse. The major limitation was that the survey likely attracted respondents who are interested in the topic creating a self-selection bias.  相似文献   
4.
Congestive heart failure was diagnosed in a 27-year-old Indian ringneck parakeet with exercise-induced dyspnea. A grade IV/VI holosystolic murmur that radiated to the right sternal area was auscultated over the left side of the sternum. Radiography revealed progressive cardiomegaly, hepatomegaly, pulmonary edema, and accumulation of fluid within the coelomic cavity. Echocardiography revealed biatrial enlargement and enlargement of the right ventricle. Doppler recording revealed high velocity left and right atrioventricular valve regurgitation. Treatment with digoxin and furosemide alleviated clinical signs for approximately 10 months. Gross postmortem examination revealed cardiac enlargement and eccentric hypertrophy of both ventricles on cross-section. Pulmonary congestion and edema, hepatomegaly, hepatic congestion, and ascites were also evident. Histologic examination of the heart revealed myxomatous degeneration of the left atrioventricular valve, muscular hypertrophy of the right atrioventricular valve, and biventricular chronic myofiber degeneration and necrosis.  相似文献   
5.
Artificial pacing (AP) is a treatment for symptomatic bradyarrhythmias unresponsive to medical therapy. This retrospective study was designed to define the practices and outcome of AP in dogs at 7 referral institutions participating in the Companion Animal Pacemaker Registry and Repository (CANPACERS). The indications, implantation techniques, complications, long-term outcome, and owner satisfaction were examined. One hundred fifty-four dogs were identified as undergoing AP from January 1, 1991, to January 1, 1996. Third-degree atrioventricular (AV) block (n = 91; 59%) and sinus node dysfunction (n = 45; 29%) were the most common indications for AP Transvenous endocardial AP systems were implanted in 136 dogs (88%), and epicardial systems were implanted in 18 (12%). Complications associated with AP were reported in 84 dogs (55%). Major complications occurred in 51 dogs (33%), including dislodgement of the pacing lead (n = 15; 10%), generator failure (n = 10; 6%), cardiac arrest during implantation (n = 9; 6%), and infection (n = 7; 5%). Minor complications occurred in 47 dogs (31%), including seroma formation (n = 18; 12%), muscle twitch (n = 17; 11%), and inconsequential arrhythmias (n = 15; 10%). Fourteen dogs (9%) experienced both major and minor complications. Survival analysis revealed 1-, 2-, and 3-year survival rates of 70, 57, and 45%, respectively. Age and presence of preexisting congestive heart failure (CHF) had a negative effect on survival (P = .001). Sixty percent of dogs with preexisting CHF died within 1 year of implantation, whereas 25% of dogs without heart failure died during the same period. Owners rated their satisfaction with the procedure as high in 80% of the dogs.  相似文献   
6.
Adenovirus infection was the cause of an epizootic of hemorrhagic disease that is believed to have killed thousands of mule deer (Odocoileus hemionus) in California during the latter half of 1993. A systemic vasculitis with pulmonary edema and hemorrhagic enteropathy or a localized vasculitis associated with necrotizing stomatitis/pharyngitis/glossitis or osteomyelitis of the jaw were common necropsy findings in animals that died during this epizootic. To study transmission of adenovirus infection in deer and susceptibility of black-tailed deer (Odocoileus hemionus columbianus) fawns to adenovirus infection, six 3-6-month-old black-tailed fawns were divided into two treatment groups. One group was inoculated intravenously and the other group was inoculated through the mucous membranes of the eyes, nose and mouth with purified adenovirus. Each treatment group also included two additional fawns (four total) that were not inoculated but were exposed to inoculated animals (contact animals). One fawn served as a negative control. Between 4 and 16 days postinoculation, 8/10 fawns developed systemic or localized infection with lesions identical to lesions seen in animals with natural disease that died during the epizootic. Transmission was by direct contact, and the route of inoculation did not affect the incubation period or the distribution of the virus (systemic or the localized infection). Immunohistochemical analysis using polyclonal antiserum against bovine adenovirus type 5 demonstrated staining in endothelial cells of vessels in numerous tissues in animals with systemic infection and endothelial staining only in vessels subtending necrotic foci in the upper alimentary tract in animals with the localized form of the disease. All inoculated or exposed animals had staining in the tonsillar epithelium. Transmission electron microscopic examination of lung and ileum from two fawns with pulmonary edema and hemorrhagic enteropathy demonstrated endothelial necrosis and adenovirus virions in endothelial cell nuclei. Adenovirus was reisolated in black-tailed deer pulmonary artery endothelial cells using lung homogenate of the first fawn that developed systemic adenovirus infection. Serum virus neutralization test results suggest that this deer adenovirus is a new serotype.  相似文献   
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Monensin, a polyether ionophore antibiotic, is potentially an important agent for bloat relief in dairy cows grazing temperate legume-based pasture. A series of studies was undertaken to determine the effect of monensin, when delivered continuously in the rumen of lactating dairy cows by means of controlled-release capsules (monensin CRC). Such devices release approximately 300 mg/head/day for 100 d. A short-term pilot study made at Ruakura, New Zealand, tested monensin CRC in cows selected for high susceptibility to bloat and grazing lucerne (Medicago sativa) or red clover (Trifolium pratense). Treatment significantly reduced the incidence of bloat, while milk yield and protein yield were increased. There was no effect on fat yield. Following the pilot study, 6 large-scale field experiments involving a total of 368 lactating dairy cows, were made in Australia and New Zealand to confirm the effectiveness of monensin CRC for bloat control and to measure the effect of such treatment on milk production and composition. A severe bloat problem occurred in 2 experiments, mild bloat occurred in 2 others, while no visual signs of bloat were observed in the remaining 2 experiments. Bloat was significantly (P less than 0.05) reduced by monensin CRC treatment when data was pooled over the 4 experiments in which bloat occurred. Daily milk yield was increased in all experiments from a mean of 17.7 in untreated groups to 18.8 kg/head/day (P less than 0.05) in monensin CRC-treated cows. Protein percentage was not affected by treatment, while there was a decrease from 4.29 to 4.10% fat, although total fat yield was not affected.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Young lambs, inoculated with ovine adenovirus isolate RTS-151, were killed sequentially (to postinoculation day 21), and their morphologic lesions were studied. Lesions were found only in the respiratory tract and were most severe in the terminal airways. Many cells of the respiratory epithelium had severe cytomegaly and karyomegaly with intranuclear inclusions. Desquamation of affected cells was accompanied by hyperplasia of airway and alveolar epithelium and by accumulation of necrotic cellular debris and neutrophils in terminal airways and alveoli. Virus replicated in the nucleus of enlarged epithelial cells in the airways, but not in alveolar epithelium. Intranuclear inclusions representing viral replication progressed from clumps of finely granular material without virions to a granular material with virions and finally to a dense inclusion with numerous virions.  相似文献   
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