Age Concerning Sexuality and Spermiogram of Malpura Rams in Semi Arid Tropics

Abstract

Aims: In the realm of sustainable livestock production, extending the productive lifespan of breeding stock could be an important strategy for enhancing economic viability and resource efficiency. Such information is not available for the ram that is native to semi-arid tropics. Hence the study aimed to evaluate the sexuality and spermiogram of young and old Malpura rams raised and maintained in the semi-arid subtropical region of northwest India. Place of Study: Animal Physiology and Biochemistry Division, ICAR-Central Sheep and Wool Research, Avikanagar, Rajasthan. Methodology: Rams were distributed equally into two groups categorized on age: G1 (2-3 years, n=13) and G2 (6-7 years, n=13). Semen was collected biweekly over six weeks during May-July 2024 for evaluating the spermiogram. Amongst the sexual behaviors, time to mount, number of mounts, ejaculation time, nudging, pawing, and flehmen response were observed. Results: The older rams (G2) mounted more quickly (2 ± 0.35 s vs. 3 ± 0.48 s) and exhibited more frequent nudging and higher pawing behavior than the younger rams in G1. Semen volume was significantly lower in G2 (0.71 ± 0.10 ml vs. 1.15 ± 0.14 ml, p<0.05), with a higher percentage of watery samples (10.71% vs. 0%). However, sperm concentration, mass motility, viability and morphology showed no significant differences (p>0.05). Conclusion: While aging reduces semen volume, possibly due to diminished seminal vesicle and accessory gland efficiency, Malpura rams aged 6-7 years remain viable for breeding owing to comparable sperm quality and enhanced sexual behavior with the younger rams of 2-3 years of age.