Embryonic and foetal mortality in buffalo species

The aim of this study was to verify the incidence of late embryonic mortality (between 25 and 45 days post-insemination; LEM) and foetal mortality (between 45 and 70 days postinsemination; FM) in buffaloes synchronized and mated by AI during the transitional period. The trial was performed on 288 multiparous Mediterranean Buffaloes, synchronized and inseminated by AI. Trans-rectal ultrasonography was performed 25, 45, and 70 days post-insemination to assess embryonic development. Milk samples were collected on Days 10, 20, 25, 30, and 45 post-insemination to determine progesterone concentration in whey. Pregnancy rate on Day 25 after AI was 48.6% but declined to 35.4% and to 30.6% by Day 45 and 70 respectively, representing a LEM of 27.1% and a FM of 13.7%. Progesterone concentration was higher (P<0.01) in pregnant compared to LEM buffaloes after 20 days post-insemination. Differences (P<0.05) were found between FM and LEM buffaloes on Days 25 and 30. Furthermore, progesterone concentration in pregnant buffaloes was higher (P=0.09) than that of FM buffaloes on Day 30 and 45. In conclusion, the success of application of reproductive biotechnologies in the transitional period depends from the incidence of embryonic and foetal mortality.