Synchronization of oestrus by ‘buck effect’ and PGF₂alpha treatment in local indigenous goats

Abstract

The study was carried out to investigate the influence of buck effect and PGF₂α treatment on oestrus synchronization in local indigenous goats. Apparently healthy normally cycling nulliparous goats (16) were divided into 3 groups considering their age, body weight and serum progesterone concentration indicating their similar stage of oestrous cycle prior to treatment. The group 1 (control, n=4) was kept separate without treatment, the group 2 (T₁, n=6) was treated with 2 injections of PGF₂α at 11 days apart @ 7.5mg/animal/injection while the group 3 (T₂, n=6) was teased with a sexually-active-aproned buck. The proportion of females showing behavioural oestrus was successfully synchronized by double injection of PGF₂α at 11 days apart, as well as by male introduction in T₁ and T₂ groups, respectively. The time interval between start of treatment and onset of oestrus were significantly shorter in T₁ (64.00±3.35 h) and T₂ (65.00±18.50 h) than in control (264±30.24 h) group but was similar in both T₁ and T₂. However, the duration of oestrus was 30.5±1.5 h, 34.00±3.69 h and 30.00±4.38 h for control, T₁ and T₂ groups, respectively. There was no significant difference in conception rates amongst the groups. All the goats conceived after second service irrespective of treatment groups. It was found that the buck effect appeared to be as effective as conventional PGF₂α treatment in indigenous goats for synchronization of oestrus.