The effect of hormonal treatment with kisspeptin, GnRH and hCG on semen characteristics in buck Cyprus goats during non-breeding season as compared with breeding season

الملخص EN

The current study aimed to determine the effect of hormonal treatment with kisspeptin, GnRHand hCG on plasma testosterone concentration and semen characteristics in buck Cyprusgoats during non-breeding season as compared with breeding season.

This study wasexecuted at the Ruminant Researches Station pertaining to the Directorate of AgriculturalResearches, Ministry of Agriculture, Abu-Ghraib, Baghdad (latitude 33˚20' N) for the periodfrom November 15th, 2012 to December 31st 2013.

A total of 20 buck Cyprus goats 2 yearsold and averages 55 kg body weight.

During non-breeding season bucks were randomlydivided into five equal groups (4 bucks / group).

The first group (A1) was regarded as a controlgroup, i.

m injected with normal saline, whereas, the second (A2) and third (A3) groups were i.

vinjected with 4 and 8 µg / kg body weight of Kisspeptin-10 respectively.

The fourth (A4) andfifth (A5) groups were i.

m injected with hCG (250 IU / buck) and GnRH (20 µg / buck)respectively.

Plasma testosterone concentrations were significantly (P≤ 0.01 and P≤ 0.05)increased at 20, 30, 40 and 50 min post-treatment in A5, A2 and A3 groups as compared withcontrol A1.

Mass motility and individual motility were significantly (P≤ 0.01) in A5, A4, A2 andA3 as compared with control during non-breeding season.

In conclusion, our results showthat Kisspeptin-10, GnRH and hCG can stimulate the quiescent hypothalamic–pituitary–gonadal axis of bucks during non-breeding season by increasing plasma testosteroneconcentration post treatment that leads improving some semen characteristics during nonbreeding season