Effect of two oestrous synchronization protocols and further use of new or recycled implant in nulliparous and multiparous hair sheep

Abstract

The Norgestomet implant use in African sheep was carried out at Pastaza Experimental Station, of Animal Science Faculty, located in Pastaza Province. This was a one hundred twenty-six day evaluation, in the first stage the estrus synchronization was studied by means of Norgestomet subcutaneous implant in two different protocols during 7 days for ewes and replacement lambs (female). After two days the implant was extracted and FTAI (Fixed -Time Artificial Insemination) was carried out; in the second stage, (nine days post insemination), Norgestomed which was previously used, was reintroduced for protocol 1, and for protocol 2 a new one was used. This was a seven-day process in both cases and after two days the implants were extracted and the estrus nonpregnant sheep are exposed to natural mating during the first stage. This was evaluated under a completely randomized design under combinatorial settlement. When observing the experimental result, it was determined that the fecundation rate in the first stage of protocol 2 is high with a 40%, in the second stage of the protocol 1 a fecundation rate of 85.61%, in number of services per conception of protocol 2 a 1.56. In the fecundation rate the data registered in both cases are 90% and natural mating registered data in an 84.67% exceeding AI (Artificial Insemination). This proves the efficiency of both protocols with the use of new and recycled Norgestomed implant stating the importance of tropical sheep production in the Amazon Region using reproductive biotechnology.

Keywords

• hair sheep
• synchronization
• implant
• progestogen.