Suppression of humoral immunity in chickens with carrageenans     

M G Elfaki  D L Dawe  K K Murthy  O J Fletcher  W L Ragland 《Veterinary immunology and immunopathology》1987,16(1-2):139-150

Carrageenans (CGN), sulphated polygalactans, have been reported to be cytotoxic for macrophages in vitro. On this basis, the effect of the 3 major CGN types on humoral immune responses in chickens was investigated. Carrageenan had no effect on body and lymphoid organ weights. Histologically, CGN produced a significant proliferation of reticuloendothelial cells in liver and spleen, but no changes were observed in lymphocyte populations of the bursa of Fabricius, thymus, or spleen. Intracoelomic pretreatment with high doses of CGN induced a marked suppression of primary responses to sheep red blood cells (SRBC) given by the same route. However, if SRBC were injected intravenously into chickens already treated intracoelomically with CGN, no evidence of suppression was demonstrated. Antibody responses to Brucella abortus (BA), a T-independent antigen, were not affected by intracoelomic treatment with CGN. Intravenous pretreatment with CGN did not alter antibody responses to SRBC and BA given by the same route.  相似文献   

Estimate of economic impact of fowl cholera in turkeys in Georgia in 1986     

M P Morris  O J Fletcher 《Avian diseases》1988,32(4):718-721

Information gathered from cases of fowl cholera (FC) in commercial turkey flocks through case records, flock records, and telephone and mail surveys was used to estimate disease costs. The cost to the Georgia commercial turkey industry in 1986 from preventive measures, treatment of outbreaks, and production losses from the disease was estimated at $634,545. The cost of FC per kg of live production was estimated to be $0.015.  相似文献   

Disease prevalence in Georgia turkey flocks in 1986     

M P Morris  O J Fletcher 《Avian diseases》1988,32(3):404-406

Disease prevalence in turkeys was estimated by totaling the flock size of necropsy cases submitted to the University of Georgia in 1986 for each disease reported and comparing it with the population at risk. Fowl cholera was the most prevalent disease in both commercial tom flocks (18.0%) and breeder hen flocks (14.7%). Prevalence of colibacillosis was 15.9% in commercial tom flocks, and prevalence of aspergillosis was 8.5% in commercial tom and 4.9% in breeder hen flocks.  相似文献   

Reply     

DA SHUTT  LR FELL 《Australian veterinary journal》1988,65(12):404-404

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Evaluation of ciliary movement in tracheal rings to assess immunity against infectious bronchitis virus     

L F Andrade  P Villegas  O J Fletcher  R Laudencia 《Avian diseases》1982,26(4):805-815

Chickens vaccinated at one and 14 days of age with a live vaccine containing the Massachusetts and Connecticut strains of infectious bronchitis virus were protected against challenge with a Massachusetts strain administered at 5 weeks of age. The virus recovery method in which tracheal swabs taken 4 days post-challenge were used to inoculate chicken embryos was compared with the method based on ciliary activity in tracheal explants. The results showed that evaluation of ciliary activity effectively measured immunity to infectious bronchitis virus. Serological results obtained in a microneutralization test using chicken embryo kidney cells correlated with the immune status of the birds as well as with the alpha neutralization results obtained using chicken embryos.  相似文献   

Studies on the Overwintering of Tomato Mosaic in Root Debris     

J. T. Fletcher 《Plant pathology》1969,18(3):97-108

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Immunoquantitation of transferrin in chickens with lymphoid tumors     

O J Fletcher 《American journal of veterinary research》1971,32(7):1121-1123

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Measurement of serum IgG in foals by radial immunodiffusion and automated turbidimetric immunoassay     

Davis DG  Schaefer DM  Hinchcliff KW  Wellman ML  Willet VE  Fletcher JM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(1):93-96

Hypogammaglobulinemia as a result of failure of transfer of passive immunity (FTPI) is an important risk factor for infectious disease in neonatal foals. The current gold standard for determining serum immunoglobulin concentrations is radial immunodiffusion (RID). The purpose of this study was to compare immunoglobulin concentrations measured by RID with those determined by an automated turbidimetric immunoassay (TIA), which has a much shorter turnaround time. Immunoglobulin concentrations were measured by both RID and TIA in serum collected from 84 neonatal foals. Sixty-seven foals had results within the linear range for both assays. Sensitivity and specificity of TIA for diagnosis of FTPI with IgG < or = 800 mg/dL were 0.81 (95% CI 0.70-0.88) and 0.86 (95% CI 0.76-0.93) and with IgG < or = 400 mg/dL were 0.63 (95% CI 0.35-0.86) and 0.92 (95% CI 0.87-0.95), respectively. A significant linear relationship was found between IgG concentrations determined by TIA and RID (TIA = 0.9511RID + 8.4354; R2 = .59, P < .0001). The coefficients of variation for between-run and within-run precision for the TIA were 2.5 and 3%, respectively. Storage of samples from 10 foals at -20 degrees C for 10-12 months resulted in a reduction in TIA-measured serum IgG concentration of -17.6% (SD = 3.7%), indicating that long-term storage of samples at -20 degrees C should be avoided. The results of this study indicate that measurement of serum IgG by TIA can be used to evaluate foals for FTPI.  相似文献   

Histologic features of transplantable lymphoid tumor (Olson) during growth and regression induced by serum therapy     

M M Walser  O J Fletcher 《Avian diseases》1977,21(4):508-513

Susceptible 3-week-old chicks were inoculated with cells of an avian transplantable lymphoid tumor (TLT) and then treated with serum from immune chickens, serum from control chickens, or balanced salt solution. Progressive tumor growth was observed in chickens of all 3 treatment groups. Tumor growth was followed by regression only in chicks treated with immune serum. Regression was characterized by necrosis of tumor cells, muscle regeneration, and lymphocyte and plasma cell infiltration.  相似文献   

Hypersensitivity of an isolated population of red deer (Cervus elaphus) to xylazine     

J Fletcher 《The Veterinary record》1974,94(5):85-86

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