Sperm motion characteristics of FecBBB and FecBB+ Garole x Malpura rams during the non-breeding season under hot semi-arid environment

A trial was conducted to assess the semen production potential of FecB gene carrier Garole x Malpura rams during the non-breeding season and to evaluate objectively their semen quality by computer-aided semen analysis (CASA) technique. Semen was collected from 4 homozygous (FecBBB) and 11 heterozygous (FecBB+) adult Garole x Malpura rams on 8 occasions twice in a week. The data derived from CASA estimates were subjected to repeated measures analysis. The overall means of traits which did not differ significantly with age or FecB genotyping were volume (0.6 ml), mass motility (4.52), sperm concentration (3714.6×106/ml), motility (91.4%), rapid motile (83.0%), linearity (61.1%), curvilinear velocity (234.9 μm/s), average path velocity (168.7 μm/s), straight-line velocity (147.5 μm/s), amplitude of lateral head displacement (6.93 μm), sperm head elongation (48.8%) and sperm head area (6.96 μm2). The age of rams had significant effect (P<0.05) on the percent straightness of spermatozoa, which was higher in young rams (<4 yr) compared to old ones (>4 yr). However, straightness was not significantly affected by the FecB status of semen donor rams. The results indicate that FecBBB and FecBB+ Garole x Malpura rams are capable of producing good quality semen during the non-breeding season in a hot semi-arid climate.