​Evaluation of Level of Pesticide Residue in Seminal Fluid of Crossbred Bulls

Background: Pesticides act as endocrine disruptors and cause enormous disturbances in steroidogenesis, spermatogenesis and sexual behavioural display. These toxicants modulate and/or disrupt the reproductive and hormonal environment by acting on hypothalamus, pituitary and reproductive organs. Few studies have been carried out to assess the levels of pesticides in dairy cattle / buffaloes. The information on pesticide residues in body fluids especially blood and semen in breeding bulls is lacking. Method: In the light of above background nineteen fresh semen ejaculates were collected from Milkfed, Khanna and PLDB (Punjab Livestock Development Board), Nabha, Punjab and stored at -80◦C. Immediately after collection, the semen was centrifuged at 4500 × g for 20 min at 4◦C. The supernatant (seminal plasma) was stored at -20◦C until processing for the assessment of pesticide residues using gas chromatography (GC). In the present study on crossbred breeding bulls, the semen samples were analyzed for organochlorines, organophosphates and synthetic pyrethroid pesticide residues. Seven OCP were screened namely Heptachlor epoxide, Chlordane, Fipronil, Lindane, Methoxychlor, op-DDT, Endrin. Eleven OPP were screened namely Chorpyrifos, Dichlorovos, Ethion, Monocrotophos, Malathion, Parathion-methyl, Profenphos, Phorate, Triazophos, Quinalphos and Phosalone and four SP’s namely Cypermethrin, Permethrin, Deltamethrin, Cyalothrin were screened in the semen samples. Semen samples were also assessed for viability, HOST (%) and abnormality (%) for both fresh as well as post thaw samples. Result: None of the semen samples were found positive for any of the above pesticide residues. This may be attributed to the feeding of fodder cultivated at the stations without using any pesticides, hence no pesticide residue found in the semen samples of the crossbred breeding bulls of these semen stations In present study, viability (%) of sperms were found to be significantly higher (p less than 0.05) in fresh (75.57 ± 5.31) as compared to post thaw (70.17 ± 4.64) semen of bulls. The abnormality (%) of sperms was found to be significantly lower (p less than 0.05) in fresh (13.61 ± 3.71) than post thaw (18.22 ± 3.59) semen bulls. Also in present study the host (%) was found 67.23±4.76 in fresh semen which decreased to 46.82±3.55 in post thaw semen.