Feed efficiency improves sperm quality and viability of fertilisation in Dorper sheep

Abstract

ABSTRACT The aim was to evaluate the influence of residual feed intake (RFI) on the semen characteristics of Dorper sheep after cryopreservation. Six Dorper sheep were used, classified from a population of 64 according to feed efficiency (groups of animals-positive RFI and negative RFI). The ejaculates were harvested three times a week, with a minimum interval of 48-h between collections, being seven collections per animal, totalling 42 ejaculates. Motility, plasma membrane integrity, acrosomal, mitochondrial activity and perivitelline membrane binding tests were performed. Negative RFI animals presented higher progressive motility (31.28%) than of RFI positive (25.37%). Negative and positive RFI animals present similar qualities in the assessment of plasma and acrosomal membrane integrity and mitochondrial activity, and negative RFI animals presented a higher number of membrane-bound spermatozoa than the positive RFI animals. Negative RFI animals displayed better rates of sperm motility after thawing, and are more efficient in the fertilisation in vitro. RFI did not influence the integrity of the plasma and acrosomal membrane, nor the mitochondrial activity of Dorper sheep spermatozoa after cryopreservation.