عنوان

The pathophysiology of astrovirus infection in hatchling turkeys

Number

TLpq303983084

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

The pathophysiology of astrovirus infection in hatchling turkeys

General Material Designation

[Thesis]

First Statement of Responsibility

M. L. Thouvenelle

Subsequent Statement of Responsibility

J. S. K. J. P. Haynes

Name of Publisher, Distributor, etc.

Iowa State University

Date of Publication, Distribution, etc.

1992

Specific Material Designation and Extent of Item

145-145 p.

Dissertation or thesis details and type of degree

Ph.D.

Body granting the degree

Iowa State University

Text preceding or following the note

1992

Text of Note

Experiments were conducted to determine the effect of astrovirus infection in hatchling turkeys. Additionally, the lectin-binding affinities of the small intestinal glycocalyx were investigated by direct biotin-strep-avidin technique in poults. Two to 5 day old poults were inoculated orally with astrovirus. Poults were examined on days 0.5 to 14 post inoculation (PI). Histopathological changes were documented by computerized image analysis, localization of virus was accomplished by transmission electron microscopy, and specific maltase activity was determined by intestinal disaccharidase analysis. Poults on days 2 through 10 post inoculation (PI) had diarrhea, generalized loss of intestinal tone and dilatated ceca containing fluid to semi-solid feces and gas. Progressive mild crypt hyperplasia was noted 1 day PI in the proximal jejunum and by day 3 in the distal jejunum and ileum. The duodenum was affected on days 5 and 7 PI. Significant (P <.05) increases in crypt depth and area in the distal jejunum and ileum were documented by image analysis on day 3 PI. The majority of the small intestine was affected seven days after inoculation. Intracytoplasmic crystalline arrays of astrovirus were found in the ileal villous enterocytes on days 2 and 3 PI, but only on day 3 in the distal jejunum. Specific maltase activity (SMA) was decreased (P <.05) in the entire small intestine of inoculated poults 3 to 7 days PI. On day 10 PI, no significant difference (P >.05) was detected in SMA levels in inoculated versus control poults. However by day 14 PI, SMA levels were increased in all sections of the small intestine of inoculated poults, except the proximal jejunum. There was no definitive staining of the glycocalyx with any of the 15 lectins evaluated, irrespective of regional location or age. Experimental astrovirus produced typical clinical signs and gross lesions associated with enteric disease. Only subtle histopathological changes were noted, however significant and consistent morphometric changes were documented. Astrovirus appeared to replicate in villous enterocytes of the distal small intestine. Maldigestion was the primary pathogenic effect in the small intestine. The small intestine of young poults does not have a definitive histochemical lectin-binding pattern based on this study.

Animal diseases

Biological sciences

turkeys

Veterinary services

J. S. K. J. P. Haynes

M. L. Thouvenelle

Electronic name

p

[Thesis]

276903

a

Y