Effects of parity and body condition score (BCS) on oestrus expressions and post breeding reproductive performance of Katjang crossbred goat

Abstract

This experiment goal was to identify the effect of parity and body condition score (BCS) on oestrusexpressions (OE), post breeding reproductive performance (PBRP) of Katjang crossbred andchanges of progesterone (P4) concentration. Twenty-four does were treated with 14 dayssynchronisation followed by visual observation of oestrus expressions (standing heat (SH),mounted by other buck but not standing (MBNS), vocalization (VC), tail swaging (TW), andsniffing of the genital of other buck (SGB)) and blood sampling twice daily up to 72 hours followingControl Internal Drug Release (CIDR) removal. PBRP data was recorded for evaluation whichincluded pregnancy rate (PR), abortion rate (AR), mortality rate (MR), litter size (LS), litter birthweight (LBW) and gestation length (GL). Result revealed that there was no significant effect(P>0.05) of parity and BCS on OE, PBRP and progesterone concentration except for birth weightwhich had been affected by parity. Based on observation of OE of SH, it was found that accuracyof pregnancy prediction was up to 50%. Analysis of OE established reliability of OE in wassequence from SH>SGB>TW>MBNS>VC and onset of oestrus began approximately 33h post toCIDR removal. Analysis of PBRP shown parity?2 had heavier birth weight in single litter size thanparity?3 which was associated with no MR. Progesterone concentration indicated all of the doeswere on oestrus and highly susceptible as early as 48 h post to CIDR removal. In conclusion, thisstudy demonstrated that both non-genetic factors; parity and BCS are very poor in determining theeffect of OE, PBRP and P4 concentration due to limitation of sample size and greater influences ofexternal factors such as weather, extreme environmental condition and farm management. It isrecommended to improve program in future by focusing on enhancing the fertilization rate andreducing embryonic loss for optimum conception rate.