Use of artificial insemination and oestrus synchronisation in beef herds

Abstract

The use of artificial insemmination (AI) in beef herds has been increasing in the last two decades especially when used in conjunction with oestrus synchronisation (OS) protocols. The resultant improvement in reproductive efficiency has a significant impact on productivity and profitability, particularly in seasonal block calving beef herds. Within this it is key that the nulliparous heifers calve down promptly in the block, and if these heifers can have heifer calves it will expediate genetic gain. This article reviews the benefits of using AI and the OS programmes commonly used, including those involving prostaglandin F 2 alpha (PG) alone, progesterone-releasing devices either with PG or with gonadotropin-releasing hormone and PG or with additional equine chorionic gonadotropin. It also comments on the relatively new ‘7 and 7 Synch’ protocol as well as approaches to pre-synchronisation, non-cycling beef cows, late-calving beef cows and pre-pubertal heifers.