Caractéristiques des chaleurs et moment de l’ovulation chez la femelle zébu (Bos indicus) Azawak

The characteristics of heats and the ovulation time were given for the female of Azawak zebu (Boss indicus). The heats were induced by implants CRESTARND (with simultaneous injection IM of oestradiol valerate) or vaginal spirals PRIDND maintained in place for 9 days, with injection of 1 mg of PGF2α the 7th day and 350UI of PMSG the 9th day. Estrus Characteristics were appreciated in a 1st protocol with 12 cows synchronized with the CRESTAR, by direct observation. The ovulation time was given in a 2nd protocol with 5 cows on induced heats (3 with implants CRESTAR, and 2 with the vaginal spirals) and 3 others in natural heats, by transrectal echography carried out each 8 hours, from the end of treatment to the ovulation observation. The rate of estrus induction was 100%; they appeared on average 43±7,8h after the end of the treatment. They duration average was 17,7 ± 4,1h. Ovulation was noted during the estrus, in the 10 h after the beginning, for 4 of the 5 synchronized animals, while for the 5th that was at 72h after the end of the treatment without estrus observation. This result suggests that, for insemination after heats observation, it is necessary to make the first artificial insemination as of the appearance of heats, and the 2nd one half-day later