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Objective: To study gross and histopathologic lesions and
also relative weight of liver in experimental aflatoxicosis in Ross broiler chicks.
Design: Experimental study
Animals: Two hundred and forty 1-day-old Ross broiler
chicken. Statistic analysis: Linear model analysis and Duncan's
method for mean values with SAS package.
Procedure: The chickens were fed by NRC (1994) diet.
Feed and water were provided ad libitum. The diets were
divided into 3 groups: control(0 or basal) and treatment
with 1 and 2 ppm of aflatoxin. Aflatoxin was produced
by infecting of autoclaved rice with Aspergillus
parasiticus NRRL-2999 in the flasks and titrated by TLC
and HPLC. After 21 and 42 days, three chickens from
each group randomly killed and their livers were weighed. Tissue samples were collected and fixed in
10% neutral buffered formalin, embedded in paraffin,
sectioned at 5 um and stained by haematoxylin and eosin
(H&E).
Results: Relative weights of the livers (g/100g.b.w) in
treatment groups were significantly increased as compared
with control (p cells, fibrosis of portal regions and bile ductule
hyperplasia. The lesions were very severe in 42-days-old
chickens and had the lesser severity in 21-days-old chickens. Conclusion: Liver is the target organ for aflatoxin.
Aflatoxin causes severe lesions in the liver and increases
its relative weight. Prolonged exposure to low
concentrations of toxin produces severe changes in fat
metabolism and bile ductules proliferation. J.Fac.Vet. Med. Univ. Tehran. 6O,3253-257,2OO5.