Pregnancy and calving rates improved using modified swim-up method for buffalo semen sexing.

Present study aimed to evaluate field fertility rate and calf sex ratio of Nili Ravi buffalo semen sexed through modified swim-up method (Animal Reproduction Science, 182, 2017, 69). For this purpose, five mature Nili-Ravi buffalo bulls kept at semen production unit, Qadirabad, Pakistan, were selected. Two consecutive ejaculates per week were collected with artificial vaginą for 3 weeks. Qualified semen ejaculates were pooled and divided into two aliquots. The first aliquot was processed by routine procedure (control), whereas the second was processed by modified swim-up technique. After separation, semen was diluted in tris-citric acid extender and cryopreserved using standard techniques. Sexed semen was evaluated for fertility trials during peak breeding season. Artificially inseminated animals were examined for pregnancy rate through rectal palpation at least 3 months after insemination under field conditions. Calving ratio of female and male calves were recoded after Parturition. The fertility rate was higher (p < .05) in X-sorted sperm (70%) as compared with control (47%). The female calf ratio was higher (p < .05) in X-sorted sperm (78.58%) compared with control (53.3%). In Conclusion, conception rate and production of female calf were significantly higher with sexed semen separated through modified swim-up method compared with unsexed control.