Abstract

The aim of this study was to use mixture of tannic acid and caffeine in a dose of 600 mg + 750 mg as 3 ml solution injected in the testes for induce castration in donkey. Sixteen apparently healthy male local breed donkeys were used. The animals were divided in to three groups, the first one include 6 donkeys injected intratesticular with 3 ml mixture of 600 mg tannic acid and 750 mg Caffeine, the second group which include 6 donkey injected with distilled water and considered as control group, while the third group include 4 animals, one testes injected with the mixture while the second testes was injected with distilled water. All injections were done under effect of xylazine at a dose 1mg/kg, B.W, i.v. in the standing position. All animals kept under observation one month after castration, blood was collected from jugular vein in group 1 and 2 before injection then 15, 30 days after injection to measure testosterone level by radioimmunoassay, while in the third group blood collected before injection and 30 days after injection to measure Alanine aminoransferase (ALT) and Aspirtate aminotransferase (AST) activity. Results show that chemical castration can be done in donkey by injection mixture of (600 mg tannic acid + 750 caffeine) intra testicularly. The result proved by clinical, hormonal, and histopathological study. The injection leads to swelling of scrotum for more than 3 weeks, then returns near the normal size but with irregular shapes. The hormonal analysis shown significant decrease in the testosterone level at 15 days after injection and continued even 30 days compared with the level of the hormone before injection. Necropsy findings of the first group injected with mixture show sever adhesions between scrotum and testis and histopathological examination showed sever necrosis in the epithelium cells of the somniferous tubules and the somniferous tubules appeared free from sperms. In conclusion this study showed that chemical castration can be done in donkeys by injection the testis with a mixture of (600 mg tannic acid + 750 mg caffeine), with good results.