L-Carnitine Improves Cytoprotection during Cryopreservation: A case study on Nili-Ravi Buffalo Sperm

Abstract
The current study was aimed to evaluate the antioxidative effect of L-Carnitine at post thawing following cryopreservation of Nili-Ravi buffalo sperm. For this purpose, semen from three buffalo bulls were collected for 3 weeks using an artificial vagina (N=18; replicates). The qualified ejaculates were diluted employing tris-citric acid extender i.e., control did not receive any L-Carnitine and experimental groups having 0.5, 1.0, and 1.5 ng/mL of L-carnitine at 37 C with approximately 50 x 106 sperm/mL. The semen was cooled at 4 C and then equilibrated (4 hours), filled in straws (0.5 mL) at4 C, placed on LN2 vapours for 10 min, and kept into an LN2 container. The thawed semen was evaluated for post-thaw quality. The integrity of the sperm plasma membrane and motility (P?0.05) was highest in the extenders having 1.0 ng/mL of L-carnitine as compared to the control(received no L-Carnitine). However, sperm chromatin integrity and viability(live sperm with intact acrosome) remained similar. It was concluded that supplementing 1.0 ng/mL L-Carnitine of extender can improve the post-thaw quality of cryopreserved sperm. Based on the results of the current experiments it is recommended to include L-carnitine extender to improve post-thaw quality of buffalo sperm in terms of its motility and integrity ofits plasma membrane. Keywords: Buffalo, Sperm, Cryopreservation, Extender, L-Carnitine, Artificial insemination.