Post-partum anoestrus in Anglo-Nubian and Saanen goats raised in semi-arid of North-eastern Brazil

Abstract

The aim of this study was to verify the length of post-partum anoestrus (PPA) in Anglo-Nubian and Saanen goats raised in North-eastern Brazil. Thirty-four Anglo-Nubian and 25 Saanen goats were used and the following parameters were observed: parity (order I or II), type of parturition (single or multiple), length of PPA, type of oestrous cycle, milk production and body condition score (BCS). No significant difference ( P>0.05) was observed between breeds for PPA length. Concerning order I, Saanen goats showed a higher PPA when compared to Anglo-Nubian ( P<0.05). In both breeds, order I goats showed a higher PPA than order II ( P<0.05). Concerning the type of parturition, no significant difference was observed for the length of PPA. Anglo-Nubian goats showed a shorter first oestrous cycle length (mean±S.E.M.) (23.89±5.64 days) when compared to Saanen goats (46.20±9.50 days) ( P<0.05). For both breeds it was observed a greater proportion of long oestrous cycles ( P<0.05). Saanen goats showed higher daily milk production in comparison to Anglo-Nubian breed ( P<0.001). A significant fall in BCS was observed ( P<0.05) in both breeds. In conclusion, when raised in North-eastern Brazil, Saanen goats showed more efficient milk production but presented a longer PPA in primiparous females.