The relationship of estrus character before double dose artificial insemination in Limousin Crossbred cow

Keys to Successful Estrus Synchronization and Artificial Insemination Programs

Introduction The development of effective methods of synchronizing estrus and ovulation has been based on our understanding of the physiological and hormonal mechanisms controlling the estrous cycle and the initiation of estrous cyclicity and prepuberty in heifers and postpartum cows. Although estrus synchronization products (PGF2, MGA, CIDR and GnRH) and protocols have changed over time, the ...

Synchronization of estrus in suckled beef cows for detected estrus and artificial insemination and timed artificial inseminati

We determined whether a fixed-time AI (TAI) protocol could yield pregnancy rates similar to a protocol requiring detection of estrus, or estrous detection plus TAI, and whether adding a controlled internal device release (CIDR) to GnRH-based protocols would enhance fertility. Estrus was synchronized in 2,598 suckled beef cows at 14 locations, and AI was preceded by 1 of 5 treatments: 1) a CIDR ...

Comparison of progestin-based estrus synchronization protocols before fixed-time artificial insemination on pregnancy rate in beef heifers.

The objective of the experiment was to compare pregnancy rates resulting from fixed-time AI after administration of either 1 of 2 controlled internal drug release (CIDR)-based protocols. Heifers at 3 locations (location 1, n = 78; location 2, n = 61; and location 3, n = 78) were assigned to 1 of 2 treatments within reproductive tract scores (1 = immature to 5 = cycling) by age and BW. Heifers a...

Comparison of long-term progestin-based protocols to synchronize estrus before fixed-time artificial insemination in beef heifers.

Two experiments were conducted to compare pregnancy rates resulting from fixed-time AI (FTAI) after administration of 1 of 2 long-term controlled internal drug release (CIDR)-based protocols. Heifers were assigned to treatment by age, BW, and pubertal status. The CIDR Select-treated heifers (Exp. 1, n = 37; Exp. 2, n = 192) received a CIDR (1.38 g of progesterone) from d 0 to 14, followed by 10...

On-line prediction of fatty acid profiles in crossbred Limousin