85 Conception Rates in Beef Cattle Inseminated with Either Sexedultra™ Sex-Sorted Semen or Conventional Semen after Estrus Is Synchronized for Fixed Time Artificial Insemination Using 7-Day Co-Synch

Abstract The objective of this study was to compare conception rates of female beef cattle inseminated at a fixed-time with either conventional (CON) or SexedULTRA™ sex-sorted (SU) semen. Treatments included CON or SU with two sires represented within each treatment. Cows (n=316) and heifers (n=78) from six locations were randomly assigned treatment. Estrus was synchronized in all females using the industry-standard 7-d CO-Synch + controlled internal drug release (CIDR) protocol (gonadorelin (GnRH; 100 μg i.m., Factrel) + CIDR [1.38 g progesterone] on d 0, dinoprost tromethamine (PG; 25 mg i.m., Lutalyse) at CIDR removal on d 7, and 100 μg GnRH on d 10, 54 h (heifers) or 66 h (cows) after CIDR removal). Estrotect™ estrous detection aids were applied at CIDR removal and estrous expression was recorded at insemination. Animals were assumed estrual if greater than 50% of the patch coating was removed. Conception rates to fixed-time artificial insemination (FTAI) were analyzed using PROC GLIMMIX in SAS 9.4 and significance was determined at p