PARENT SESSION

2D - Mechanisms of toxic action
Hall 4
1:50 PM - 3:35 PM, Tuesday, 29 April 2003
Chair: Dietrich, D.¹, ¹
Co-chair: Haux, C.², ²

(TU4/12) Pathophysiological effects of chronic toxicity with different pesticides on bone health of broiler chicks.

Garg, U¹, Pal, A^{1, 2}, Jha, G¹, Jadhao, S², ¹ Ranchi Veterinary College, Ranchi, Bihar, India² Central Institute of Fisheries Education(ARS), Mumbai, M.S., India

ABSTRACT- Chickens are quite prone to chronic toxicities of pesticides, which affects not only birds but also pose danger to human health. This experiment evaluated effects of chronic toxicity through feed with 20 ppm fenvalerate (synthetic pyrethroid), 2 ppm monocrotophos (organophosphate) and 2 ppm endosulfan (chlorinated hydrocarbon pesticide) on bone health of broiler chicks. A total of 120 broiler chicks were divided equally into four groups and were fed mash without (control) or mixed with these pesticides for 8 weeks. The body weights and serum calcium and phosphorus levels were not significantly affected. However, serum alkaline phosphatase activity in birds showed a definite increase (P<0.01) in all treated groups. Roentgenography of the bones of control and fenvalerate intoxicated group revealed no abnormalities and had a normal pattern of growth. On the other hand, the bones of monocrotophos intoxicated group showed destructive changes at the upper part of the femur. Endosulfan intoxicated chicks had increased number of trabeculae in the medullary cavity of one bird. However, no periosteal reaction could be seen in any of the group. The microscopic alterations in the costochondral junction in the treated birds were seen. The zone of proliferation and maturation in cartilage cells was reduced. The zone of metaphysis showed reduced amount of cartilage cells and the trabeculae were thinner. The capillary scafolding of the degenerating cartilage cells was also reduced. In some intoxicated birds, transverse trabeculae in larger number could be seen in the metaphysis. The area of provisional calcification in the metaphysis was also reduced. Appositional bone growth studied by tetracycline labelling technique indicated decreased (P<0.01) active osteons in intoxicated groups (78.1, 72.5 and 66 % in fenvalerate, monocrotophos and endosulfan, respectively) as against control (with 93.6 %).

Key words: Chronic toxicity, Pesticides, broiler, bone health