The Use of PMSG/hCG Following Altrenogest in Estrus synchronized Gilts

Abstract

Twenty crossbred gilts (Landrace X Large White) were allocated, randomly to altrenogest+PMSG/hCG treated (n=10) and altrenogest (control; n=10) groups. Altrenogest+PMSG/hCG treated groups were fed with altrenogest at 20 mg./day for 18 condecutive days. Then they were injected with 1000 IU of PMSG and 500 IU of hCG at 24 h and 96 h post altrenogest withdrawal. Seventy eight percent of the control group and 100% treated group exhibited signs of estrus within 6 days post altrenogest withdrawal. The interval of estrus was reduced (P<0.05) by altrenogest. Total born and alive in control group was higher (P<0.05 and P<0.05, respectively) than the treated group. Percent of death at birth in term of still born, mumification and other cause of death at birth and the control were 1.2, 0, and 0.5 percent, respectively, and of the treated group were 0, 0.5 and 0.8 percent, respectively. These resuslts indicated that the use of PMSG/hCG following administration of altrenogest has induced estrus in gilts within 6 days.