B uffaloes have an important role in agricultural economy in several Asian and African tropical and subtropical countries through providing both milk and meat, in addition to, their draught power. Buffaloes share about half of the overall dairy production in Egypt (Borghese, 2005;Perera, 2011). Buffaloes' milk is preferable in Egypt because of its high fat and solid non-fat contents which gives the milk a good taste compared to that is of cows. Moreover, rearing of buffaloes is favored by because of their better adaptation to tropical and subtropical environment (Abdalla, 2003; El-Wishy, 2007).Buffaloes' production is largely affected by reproductive performance. Low reproductive efficiency of Egyptian buffaloes is mainly due to poor estrus detection and prolonged inter-calving interval (Singh et al., 2000; El-Wishy, 2007).