Fifty one Nili-Ravi dairy buffaloes in their last two months of gestation were selected. After parturition, rectal examination of reproductive organs was carried out until the occurrence of the first oestrus (PEI). Milk samples were analyzed for milk progesterone levels (MPL). Ovulation (POI) was confirmed by rectal palpation and MPL. Feed and blood samples were collected fortnightly and analyzed. Body condition score (BCS) was recorded on a scale of 0 to 5. Crude protein (CP) intake varied among different seasons and correlated positively with serum urea levels, POI (p<0.01) and PEI (p<0.05). Excess CPI was lower in the group showing oestrus as compared to those remaining as anoestrus (p<0.05). The dietary ratio of crude protein - metabolizable energy (CP:ME) in the oestrus animals was narrow and constant, while the anoestrus animals had a widely fluctuating one. In normal breeding season (NBS) calvers, mean serum urea level (SUL) was lower than the low breeding season (LBS) calvers. SUL was positively correlated with PEI and POI (p<0.01). Up to six months postpartum, SUL were constantly higher in anoestrus than oestrus buffaloes. Mean metabolizable energy (ME) intake was lower in the NBS calvers than the LBS calvers (p<0.01). BCS and postpartum ovulation interval were correlated with ME intake (p<0.01). Prepartum ME intake was higher in oestrous as compared to anoestrous animals (p<0.05). Higher and lower ME intakes were associated with anoestrus, while a moderate energy intake was associated with a PEI of less than 75 days. Buffaloes with poor BCS belonged to the LBS calving group and most of the NBS calving buffaloes had good BCS. BCS was negatively correlated with PEI (p<0.01) and was higher in oestrous buffaloes than anestrus. It was concluded that excess intake of crude protein, associated with higher serum urea levels and low energy intake, associated with poor body condition, are the key factors for low reproductive efficiency. It may be corrected by adopting a proper feeding strategy.