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1.
A sudden increase in mortality, preceded by a short history of respiratory signs and diarrhea, occurred in a backyard flock of 48 game chickens in the Central Valley of California. Necropsy findings included severe generalized linear hemorrhages and/or ulcers in the digestive tract, larynx, and trachea. Histology revealed severe multifocal hemorrhages and necrosis in the mucosa of the respiratory and digestive tracts, vasculitis, and necrosis of lymphoid tissue. The birds were serologically negative to Newcastle disease virus; this was consistent with an acute infection. The avian paramyxovirus type 1 isolated was characterized as velogenic viscerotropic Newcastle disease virus. A thorough epidemiologic investigation was carried out, and no other premises were found to have birds with clinical signs or evidence of exposure. The entire outbreak was limited to the original backyard flock and resolved within 14 days of the onset of clinical signs. 相似文献
2.
A flock of 4,500 Cobb broilers inoculated with Newcastle disease vaccine intra-ocular strain B1 type at 10 days of age developed clinical signs of the disease 19 days later; the mortality rate was 71%. Necropsy examinations showed characteristic lesions. Newcastle disease virus was isolated and identified in the allantoic fluid of embryonating chicken eggs by haemagglutination and haemagglutination-inhibition tests. Histopathological examination showed that follicles of the bursa were depleted of lymphocytes, had many large cavities and were being repopulated by newly formed healthy lymphocytes. Both the acute and convalescent serum samples were positive for infectious bursal disease antibodies in agar gel precipitation tests. Haemagglutination inhibition titres of the acute and convalescent sera were 20 to 80 and 80 to 640 respectively. The vaccine failure may be due to either the subclinical bursal disease or the highly pathogenic nature of the wild Newcastle disease virus. 相似文献
5.
Ten young partridges (Rhynchotus rufescens) were vaccinated with the lentogenic strain of Newcastle disease virus. Another eight unvaccinated birds were kept in close contact with the treated flock. Antibodies levels were measured over the course of 3 mo in all birds using the hemagglutination inhibition (HI) test and the liquid-phase blocking enzyme-linked immunosorbent assay (LPB-ELISA). The LPB-ELISA was standardized, and the results were compared with those obtained with the HI test. Antibodies increased after 23 days postvaccination in 16 birds with no side effects as determined by both the HI test and the LPB-ELISA. 相似文献
7.
Marek's disease was observed in quails. Gross lesions were confined mostly to the spleen and liver. Microscopic lesions were commonly seen in spleen, proventriculus, liver, and duodenum. Skin, peripheral nerves, and other visceral organs were also involved. Of 123 quails examined, 39 had serum antibodies against Marek's disease. These antibodies were detected from 11 to 17 weeks of age; the highest incidence was recorded at 15 weeks. Feather follicular antigen detected in 30 of the 95 quails was comparable to that of chicken. The disease was experimentally reproduced in susceptible quails. Marek's-disease-tumor-associated surface antigens (MATSA) were demonstrated in the peripheral leukocytes and spleen cells of affected quails. The possible source of infection and its epidemiological importance are discussed. 相似文献
8.
In a study of outbreaks of Marek's disease in quails, 220 adult quails vaccinated with herpesvirus of turkeys (HVT) were examined pathologically and serologically for Marek's disease (MD). Forty-three of the 220 quails exhibited microscopic lesions similar to those of chickens with MD. MD-virus-specific antigen was found in feather tips of 44 of the 220 birds, and the HVT-specific antibody was found in sera of 56 of the 220 birds by agar gel precipitation. There was a positive correlation between the incidence of lymphomatous changes and the presence of MD-virus-specific antigen, and there was a negative correlation between the incidence of lymphomatous changes and the presence of antibody against HVT on a flock basis. 相似文献
10.
The V4 strain of Newcastle disease virus was introduced into a small open range flock of bantam chickens, by dosing half the birds directly into the crop. As indicated by rises in titres of haemagglutination inhibition antibody, the virus spread to the uninoculated birds and persisted in the flock for two years, infecting chickens that were introduced by natural brooding and rearing. All new clutches of chicks seroconverted by 80 days of age, and the titres of adult birds showed a concurrent rise, suggesting that the chicks were amplifying the virus. The modes of spread and of persistence of the virus were not determined; although cloacal swabs were taken regularly, only one yielded virus. Antibody titres of the inoculated birds remained above the presumptive protective level of 3 (log2) for over a year, whereas the titres of birds infected by contact were generally less than 3. 相似文献
11.
A total of 1,000 one-day-old Japanese quails were distributed at random, with 5 digestible lysine levels, in 10 replicates and with 20 birds per experimental unit. The basal diet was formulated based on corn and soybean, with 200.6 g CP/kg, 2900.00 kcal/kg ME, and 8.8 g digestible lysine/kg. This basal diet was supplemented with L-lysine HCl (784 g/kg), replacing glutamic acid, and corresponding to digestible lysine levels of 8.8 g/kg, 9.8 g/kg, 10.8 g/kg, 11.8 g/kg, and 12.8 g/kg. The increase in the levels of digestible lysine produced a greater weight gain in birds with up to 12.2 and 12.1 g of lysine/kg at 40 d of age. Carcass weight increased as levels were increased to up to 11.85 g of lysine/kg, and, similarly, egg production per bird housed increased up to 12.03 g of lysine/kg. A linear increase took place in the growing phase for feathering, fat, and crude protein deposits in the carcass, feed intake, and lysine intake. Egg production and egg mass per bird per d increased linearly in the laying phase with the weight gain of birds decreasing linearly until 100 d of age, and, similarly, the feed conversion per egg mass linearly improved in function of the lysine levels. A level of 11.85 g of digestible lysine/kg in the diet, which corresponded to a lysine intake of 120.5 mg/bird/d, provided better carcass weight at the end of the growing phase and better performance at the beginning of the laying phase for the Japanese quails. 相似文献
12.
1. The inheritance of various plumage colour variants and their underlying interactions were investigated in a large flock of Japanese quail maintained at CARI (India) by conducting reciprocal crosses between four breeding stocks inheriting Pharaoh, White Breasted, White and Brown plumages, followed by test crosses. 2. Based on the proportion of plumage-colour types in the progeny, putative genotypes were determined for parents and offspring for each of the crosses. 3. The White and Brown phenotypes were attributed to the Panda (S) and Roux (Br) loci respectively in agreement with contemporary quail stocks. 4. The White Breasted plumage type present in our stock was caused by a novel mutation with dominant gene action at an autosomal locus that was not allelic to either Panda or the White feather locus. 5. A recessive epistatic action of the Panda locus (S) on White Breasted (Wb) resulted in a White colour phenotype. 6. A novel phenotype, White Breasted-Brown was co-expressed with the Br and Wb loci. 7. It was concluded that breeding for customized feather colour phenotypes in Japanese quail using colour mutations was feasible and would be advantageous in order to overcome the limitations of legislation to protect wildlife in India. 相似文献
14.
Tropical Animal Health and Production - The current study was conducted to evaluate the anti-mycotoxigenic effects of previously isolated Bacillus spp. in Japanese quails. A total of 240-day-old... 相似文献
17.
The performance of a flock of 203 crossbred ewes on a lowland farm was examined. Before lambing the ewes were run in two groups (A and B). Group A (124 ewes) produced significantly fewer marketable lambs as a consequence of neonatal and later losses. The associated clinical features were consistent with Border disease infection and the presence of the virus was demonstrated. These features were not evident in the progeny of group B (79 ewes). The market sale returns of both groups of sheep were compared and the flock performance was contrasted with that of the two previous years. The outbreak of Border disease resulted in a potential reduction of income in excess of 20 per cent. Such a loss supports the necessity for an effective control strategy for Border disease. 相似文献
18.
A pestivirus has been isolated from brain samples of two lambs suffering from clinical signs of border disease. The two identical isolates were allocated to the "true" border disease virus group concerning their reaction pattern with monoclonal antibodies and the 5'UTR sequence data. Nevertheless, alterations of phenotype and genotype in comparison with references of both BDV-subgroups have been shown. The existence of an infection with border disease virus in the flock has been confirmed by serological studies. 相似文献
20.
The pharmacokinetics of enrofloxacin and marbofloxacin was studied in Japanese quails and common pheasants. Healthy mature birds from both species and both genders were treated intravenously and orally with enrofloxacin (10 mg/kg) and marbofloxacin (5 mg/kg). After intravenous administration enrofloxacin was extensively metabolised to ciprofloxacin. Metabolites of marbofloxacin were not detected. Values of volume of distribution were respectively 4.63 l/kg and 3.67 l/kg for enrofloxacin and 1.56 l/kg and 1.43 l/kg for marbofloxacin. In quails, total body clearance values were higher than those in pheasants and other avian species. After oral application enrofloxacin was rapidly absorbed in quails, more rapidly than marbofloxacin. Pheasants absorbed both antimicrobials at a lower rate. Higher bioavailability was observed for marbofloxacin (118%). Relatively low bioavailability was established in quails for enrofloxacin (26.4%), accompanied by extensive conversion to ciprofloxacin. Generally, quails absorbed and eliminated both fluoroquinolones more rapidly than pheasants; the latter showed pharmacokinetics similar to poultry. Because of favourable pharmacokinetic properties, marbofloxacin should be preferred for oral administration in Japanese quails and pheasants for treatment of infections caused by equally susceptible pathogens. 相似文献
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