INTRODUCTIONM ithun (Bos frontalis) is a "mountain cattle" living as a semi-wild free-range in the North-Eastern Hill (NEH) region of India and responsible for the socio-cultural and economic status of the tribal population (Simoons, 1984). Latest livestock census of India (2007) indicated Mithun density and population is decreasing and is mainly due to lack of proper breeding management in the tribal regions. So proper and scientific interventions are needed from all quarters to conserve and preserve the Mithun population to enhance the socio-economic-cultural status of the tribes. Natural breeding is followed in Mithun,
Research ArticleAbstract | A study was designed to measure the semen quality parameters (SQP) such as volume, colour, concentration, mass activity, percent of sperm motility, viability, total morphological abnormality, intactness of acrosome, plasma membrane, nucleus, vanguard distance travelled by sperm in bovine cervical mucus and hydrogen ion concentration in freezable and non-freezable ejaculates of Mithun. Fifty ejaculates were collected from ten matured Mithun bulls and split to freezable and non-freezable ejaculates based on the post thaw motility (40% or more considered as freezable ejaculates). The result has shown that SQP differed significantly (P< 0.05) between the freezable and non-freezable ejaculates and freezable ejaculates have significantly (P< 0.05) higher value than the non-freezable ejaculates. However, morphological abnormality and pH were significantly (P< 0.05) higher in non-freezable than in freezable ejaculates. Mass activity was positively (P< 0.05) correlated with motility, liveability, integrity of acrosome, plasma membrane, nucleus and BCMPT and negatively correlated (P< 0.05) with morphological abnormality. Concluded that SQPs were significantly higher in freezable than in non-freezable ejaculates and indicates freezable sperm has higher structural stability than the non-freezable sperm caused freezable sperm.