Isolation of very virulent Marek''s disease viruses from vaccinated chickens in Australia     

JL McKIMM-BRESCHKIN  JT FARAGHER  J WITHELL  WM FORSYTH † 《Australian veterinary journal》1990,67(6):205-209

Very virulent Marek's disease viruses (vvMDV), defined as isolates against which the herpesvirus of turkey (HVT) vaccine provide poor protection, have been isolated from poultry flocks in both the United States and Europe. Twenty-one samples from vaccinated Australian flocks, experiencing problems with excessive Marek's disease (MD), were tested for the presence of transmissible MD viruses (MDV). Of the 16 samples which contained a transmissible agent, 14 were pathogenic in chickens, based on the development of MD lesions or depression of the bursa/body weight ratio. Of the pathogenic isolates which have been successfully typed 10 were serotype 1, and one was serotype 2 MDV. Pathogenicity of isolates varied. Several isolates caused tumours in 20-30% of both vaccinated and unvaccinated chickens. Two isolates, MPF6 and MPF23, caused tumours in more than 50% of chickens. When MPF6 and MPF23 were tested in vaccine trials bivalent vaccine gave no better protection against development of MD lesions than a monovalent vaccine. Isolate MPF23 was so pathogenic that lesions were produced in all chickens, regardless of the vaccine protocol used. Therefore vvMDV have been isolated in Australia, and unlike the vaccines tested overseas, bivalent Australian vaccines do not appear to provide greater protection against these vvMDV.  相似文献   

Serum agglutinating antibodies to Leptospira interrogans serovar canicola presumed due to serovar robinsoni infection in an Australian dog     

JT ROTHWELL 《Australian veterinary journal》1990,67(6):232-232

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An outbreak of listerial myelitis in sheep     

JT SEAMAN  MJ CARRIGAN  FA COCKRAM  GI CARTER 《Australian veterinary journal》1990,67(4):142-143

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Death due to a probable herpesvirus infection in a common wombat (Vombatus ursinus)     

JT ROTHWELL  PJ CANFIELD  CR WILKS 《Australian veterinary journal》1988,65(11):360-361

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Isolation of infectious bronchitis virus from a flock of racing pigeons   总被引：6，自引：0，他引：6  

DA BARR  RL REECE  D O'ROURKE  C BUTTON  JT FARAGHER 《Australian veterinary journal》1988,65(7):228-228

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Johne's disease in alpacas (Lama pacos) in Australia     

SE RIDGE  JT HARKIN† ‡  RT BADMAN†  AM MELLOR§  JWA LARSEN¶ 《Australian veterinary journal》1995,72(4):150-153

SUMMARY: Johne's disease was diagnosed in 10 alpacas ( Lama pacos ) in Australia between February 1993 and May 1994. Eight of the animals were between 12 and 24 months of age, one was a 6-year-old female, and one was a 4-year-old male. Five, including the 6-year-old and the 4-year-old alpacas, showed weight loss and diarrhoea before death or slaughter. The other cases showed no clinical signs of Johne's disease but 4 gave a positive result on faecal culture and one gave a positive result on testing with the caprine ACID assay and had acid-fast organisms in its faeces. At necropsy, all cases had grossly enlarged mesenteric lymph nodes. Johne's disease was diagnosed after histological examination of the lymph nodes with conventional culture and polymerase chain reaction testing of tissue samples. This report outlines the clinical, epidemiological, and pathological findings in these cases.  相似文献   

Antibody response to and maternal immunity from an experimental psittacine beak and feather disease vaccine.     

B W Ritchie  F D Niagro  K S Latimer  W L Steffens  D Pesti  R P Campagnoli  P D Lukert 《American journal of veterinary research》1992,53(9):1512-1518

Adult umbrella cockatoos, Moluccan cockatoos, African grey parrots, and a yellow-headed Amazon parrot were inoculated IM or SC with beta-propiolactone-treated psittacine beak and feather disease (PBFD) virus. Thirty- to 45-day-old African grey parrot, umbrella cockatoo, and sulphur-crested cockatoo chicks also were vaccinated with the same inoculum. The hemagglutination inhibition (HI) and agar-gel diffusion tests were used to assay for post-vaccination development of anti-PBFD virus antibodies. All adult vaccinates seroconverted and had increases in HI and precipitating antibodies. The vaccinated chicks had increased concentrations of HI antibodies, but precipitating antibodies could not be detected. To demonstrate that chicks from vaccinated hens are protected from PBFD virus challenge, 3 African grey parrot chicks and 2 umbrella cockatoo chicks from vaccinated hens and 1 African grey parrot chick and 1 umbrella cockatoo chick from nonvaccinated hens were exposed to purified PBFD virus. Chicks from the vaccinated hens remained clinically normal during the 50-day test period. Chicks from the nonvaccinated hens developed clinical and histologic lesions of PBFD. Infected tissues from these birds were confirmed to contain viral antigen, using immunohistochemical staining techniques. The PBFD virus was recovered from the affected birds. These findings indicate that adult and 30- to 45-day-old psittacine birds will seroconvert following vaccination with beta-propiolactone-treated PBFD virus. Also, hens inoculated with beta-propiolactone-treated PBFD virus produce chicks that are, at least temporarily, resistant to virus challenge.  相似文献   

Effects of Dietary Supplementation of β‐hydroxy‐β‐methylbutyrate on Sow Performance and mRNA Expression of Myogenic Markers in Skeletal Muscle of Neonatal Piglets          下载免费PDF全文

HF Wan  JT Zhu  Y Shen  X Xiang  HJ Yin  ZF Fang  LQ Che  Y Lin  SY Xu  B Feng  D Wu 《Reproduction in domestic animals》2016,51(1):135-142

The effects of dietary β‐hydroxy‐β‐methylbutyrate (HMB) supplementation during gestation on reproductive performance of sows and the mRNA expression of myogenic markers in skeletal muscle of neonatal pigs were determined. At day 35 of gestation, a total of 20 sows (Landrace × Yorkshire, at third parity) were randomly assigned to two groups, with each group receiving either a basal diet or the same diet supplemented with 4 g/day β‐hydroxy‐β‐methylbutyrate calcium (HMB‐Ca) until parturition. At parturition, the total and live litter size were not markedly different between treatments, however, the sows fed HMB diet had a decreased rate of stillborn piglets compared with the sows fed the control (CON) diets (p < 0.05). In addition, piglets from the sows fed HMB diet tended to have an increased birth weight (p = 0.08), and a reduced rate of low birth weight piglets (p = 0.05) compared with piglets from the CON sows. Nevertheless, lower feed intake during lactation was observed in the sows fed the HMB diet compared with those on the CON diet (p < 0.01). The relative weights of the longissimus dorsi (LD) and semitendinosus (ST) muscle were higher (p < 0.05) in neonatal pigs from the HMB than the CON sows. Furthermore, maternal HMB treatment increased the mRNA levels of the myogenic genes, including muscle regulatory factor‐4 (MRF4, p < 0.05), myogenic differentiation factor (MyoD) and insulin‐like growth factor‐1 (IGF‐1, p < 0.01). In conclusion, dietary HMB supplementation to sows at 4 g/day from day 35 of gestation to term significantly improves pregnancy outcomes and increases the expression of myogenic genes in skeletal muscle of neonatal piglets, but reduces feed intake of sows during lactation.  相似文献   

Pathogenicity of Ostertagia circumcincta,O. ostertagi and H. contortus in weanling stag fawns (Cervus elaphus)     

JT Johnson  AS Familton  R McAnulty  AR Sykes 《New Zealand veterinary journal》2013,61(12)

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Photodegradation at the wood-clearcoat interface     

I. T. MacLeod  A. D. Scully  K. P. Ghiggino  P. J. A. Ritchie  O. M. Paravagna  B. Leary 《Wood Science and Technology》1995,29(3):183-189

Summary Western red cedar panels, one coated with a soft latex-based acrylic polymer clear coating and the other uncoated, were exposed outdoors under a series of cut-off filters for 50 weeks. FTIR-ATR spectra of the panels showed that the extent of delignification increased with decreasing wavelengths of the solar radiation incident at the wood surface. The results support the proposal that it is the UV component of sunlight that is primarily responsible for the degradation of lignin. The extent of loss of lignin from the surface of the exposed coated panel was significantly less than that for the exposed uncoated panel suggesting that the coating confers some protection from weathering to the underlying timber. Colorimetric measurements also showed that the degree of discoloration of the panels is related to the wavelength of the radiation penetrating the wood surface.This work was supported financially by ICI Dulux Australia and the Australian Research Council. The authors also express their appreciation for helpful discussions with G. J. Wilson of the Commonwealth of Australia Scientific and Industrial Research Organization (C.S.I.R.O.) and I. Leaver of Dulux Australia  相似文献