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Objective: In this study, the pathologic effects of methenamin in broiler chickens were studied.
Design: Experimental study.
Procedure: For these purposes 150 day-old broiler chickens of Arian breed were randomly divided into six equal groups as follows. group I: no use of methenamine (control), groupII: Daily use of
1:1000methenamine in drinking water continiously for 8 weeks. group 1II: Daily use of 2: 1000 methenamine in drinking water continiously for 8 weeks, group IV: use of
1:1000 methenamine in drinking water for one week of the end of rearing period, group V: Daily use of 4: 1000 methenamine in drinking water continiously for 8 weeks, group VI: use of 2: 1000 methenamine in water for one week of the end of rearing period. All groups were reared in same
condition and nutrition and housing except the administration of methenamine. At the end of rearing periods samples of liver and kidneys were taken for histopathologic study.
Statistical analysis: Chi square test.
Results: The microscopic lesions such as congestion, fatty change, local lymphocyte aggregation, focal heterophil aggregation were observed, in liver and in kidney, congestion, cell swelling, acute tubular necrosis, focal lymphocyte aggregation and focal heterophil aggregation were diagnosed. No significant changes were seen in treatment and control groups by chi-square test (p<0.05). Conclusion: It is concluded that oral administration of methenamine has no significant pathologic effect even with high dose and long period (8 weeks) on liver and kidneys of broiler chickens. J. Fac. Vet. Med. Univ. Tehran. 58, 4:359-362, 2003.