A.I. DRIVES PROFITABILITY
WHAT ARE THE REPRODUCTIVE DRIVERS OF PROFITABILITY IN BEEF HERDS? 1. Number of calves weaned over lifetime: How many years does she conceive, calve and wean a calf before being culled? Over how many years can the cost of developing the cow be depreciated? 2. Age and weight of calves weaned: Does she conceive early in the breeding season as a heifer and continue to calve early as a cow? Early calving cows will wean older and heavier calves. 3. Quality of calves weaned: How much value do her calves capture based on health, growth, performance, carcass merit, visual appearance, etc.? ESTRUS SYNCHRONIZATION AND TIMED A.I. CAN IMPROVE YOUR HERD IN EVERY ONE OF THESE AREAS! PROVEN DRIVERS OF PROFITABILITY: • Heifers who calved during the first 21-day period with their first calf remained in the herd longer than heifers who calved later. Early calving heifers also wean a heavier calf in each of their first six calving seasons. (Cushman et al., 2013) • Early born A.I. heifer calves as potential replacements have: o Greater weaning and pre-breeding weights o Greater number of heifers cycling prior to breeding season o Greater pregnancy rates in first breeding season o Potential improvements in breed back as two year olds • Early born A.I. steer calves have: o Greater weaning weights o Greater percentage choice or better o Greater carcass value (better carcass weight and marbling score) (Larson and Funston, 2009; Funston et al., 2011)
TIPS FOR USE OF gender SELECTED™ (SEXED) SEMEN: • Thaw semen in a clean and regulated warm water bath (95°-98°F) for 45 seconds. • Pay close attention when handling thawed straws of sexed semen to ensure you maintain 95°-98°F temperature until the semen can be deposited in the female. • Thawed sexed semen should be deposited in the female within five minutes. • It is strongly encouraged to apply estrus detection aids to help monitor heat activity and only use sexed semen in those females that display estrus. • Sexed semen may remain fertile for a shorter period of time in the female following A.I. Therefore, A.I. should be performed approximately 18-22 hours after the start of standing heat behavior.1 This is slightly later than the time recommended when using conventional (non-sexed) semen. • Manage expectations: The use of sexed semen could result in conception rates below that of conventional semen. A recent meta-analysis in Nature2 indicated that frozen-thawed sexed semen achieves 83 percent of conventional semen pregnancy rates (i.e. if you typically achieve 55 percent with conventional semen, you may achieve 46 percent with sexed semen). 1 Thomas et al. 2014. Delayed insemination of nonestrous cows improves pregnancy rates when using sex-sorted semen in timed artificial insemination of suckled beef cows. Journal of Animal Science. Vol 92, Issue 4: 1747-1752. Reese et al. 2021. The reproductive success of bovine sperm after sex-sorting: a meta-analysis. Nature Scientific Reports. 11: 17366. 2
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