The libido problem is quite common in Zebu breeding bulls at tropical condition. When Breeding Soundness Evaluation (BSE) is normal, assessing the libido problem is complicated in adult breeding bulls.The present study was conducted to investigate the peripheral luteinizing hormone (LH) and testosterone levels in Zebu breeding bulls.The single dose of exogenous GnRH (10µg buserelin acetate, intramuscular) administrated in each animal of normal libido bulls (n=3) and poor libido bulls (n= 3). The jugular blood samplings were done at 1 h, 0 h (GnRH injection) followed by up to 6 h at 1 h interval. The average basal concentration, 1 to 6 h post-GnRH administration concentration (PGA) and Area under the curve (AUC) for testosterone, LH hormones were compared between the groups. The basal concentration of testosterone and LH hormones were found significantly higher (p<0.05) in poor libido bulls than normal libido bulls. The PGA and AUC were not significantly differed between the two groups. It was clear that the peripheral rhythm of testosterone and LH hormones were not useful to trace the libido problem in Zebu breeding bulls at the breeding centre.

No abstract

No abstract

In Bactrian camels, the seminal plasmas ovulation inducing effect was reported around 30 years ago and the substance responsible was termed as ovulation-inducing factor (OIF). Studies have confirmed that in llamas and alpacas based on biological and chemical properties, OIF was identified as βNGF. OIF is a highly conserved protein and studies have revealed that presence and function of seminal OIF are conserved among species that are considered to be induced ovulators as well as those of spontaneous ovulators. Abundant amounts of OIF/NGF in seminal plasma