عنوان

Effects of T-2 toxin on vaccinal immunity against Marek's disease and on the immune system of white leghorn chickens

Number

TLpq304257352

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

Effects of T-2 toxin on vaccinal immunity against Marek's disease and on the immune system of white leghorn chickens

General Material Designation

[Thesis]

First Statement of Responsibility

E. Kufuor-Mensah

Name of Publisher, Distributor, etc.

Michigan State University

Date of Publication, Distribution, etc.

1996

Specific Material Designation and Extent of Item

184

Dissertation or thesis details and type of degree

Ph.D.

Body granting the degree

Michigan State University

Text preceding or following the note

1996

Text of Note

Four trials were conducted to determine the effects of T-2 toxin on vaccinal immunity against Marek's disease (MD). Day-old, RPRL line 15I5 x usd7\sb1usd chicks were treated daily for seven days via crop gavage with T-2 toxin at a subclinical dose of 1.25 mg/kg body weight. Treated and untreated chicks were vaccinated with herpesvirus of turkeys (HVT) at hatch and challenged with JM strain of MD virus (MDV) at 8 days of age. Chickens were tested for HVT and MDV viremia and were observed for the development of MD lesions within 8 weeks of age. T-2 toxin significantly reduced body weight by 7 days after treatment. T-2 toxin shortened the incubation period for the development of MD lesions and mortality, but only in unvaccinated, challenged chickens. T-2 toxin also significantly reduced titres of HVT viremia within 7 days post-vaccination. However, the percent protection from MD in T-2 toxin-treated, HVT-vaccinated chickens ranged from 82%-95% and was comparable to that in untreated chickens (89%-100%). In a second experiment, the effect of T-2 toxin on peripheral blood and splenic B- and T-lymphocyte subpopulations was evaluated using flow cytometry. Day-old, 15I5 x usd7\sb1usd chicks were treated daily for 7 days via crop gavage with T-2 toxin at a subclinical dose of 1.25 mg/kg body weight. Peripheral blood and splenic lymphocytes from T-2 toxin-treated and untreated control chicks were analysed for phenotypic expression of CD4, CD8, CD3 and IgM cell surface markers at 8-9, and 21-22 days of age. The percentages of both peripheral blood and splenic B-lymphocytes in T-2 toxin-treated chickens were significantly lower than that in untreated chickens but only at 8-9 days of age. However, at 21-22 days of age the percentages of B- and T-lymphocytes were comparable to untreated chickens. The data suggest that exposure of chickens to T-2 toxin may influence the development of (a) HVT viremia; and (b) MD lesions and mortality, but only in unvaccinated chickens. The data also suggest that T-2 toxin may severely deplete B-lymphocytes and relatively increase CD4 and CD3 T-lymphocytes.

Animal diseases

Biological sciences

Health and environmental sciences

Immunology

Pathology

Toxicology

E. Kufuor-Mensah

Electronic name

p

[Thesis]

276903

a

Y