Last week we compared the costs per pregnancy for natural service and for a breeding system that included estrus synchronization and AI (ESAI). Considering the current costs of feed and pasture, the cost per pregnancy for natural service ranged from $38 to $72 when producers ran their bulls with 25-30 cows and the purchase price of the bull ranged from $1,500 to $3,000. The cost per pregnancy of the more popular ESAI protocols is from $65-75 depending mainly upon the conception rate to AI. Therefore, if the average cost per pregnancy is about $50, then using ESAI will add $15 to $25 to our costs of production. The question then becomes, does using ESAI increase our productivity enough to overcome this added cost of production.
Little data can be found in the literature that examines the return on investment of incorporating estrus synchronization and AI. We designed a trial to determine if implementation of estrus synchronization and AI is cost effective and impacts net return. Crossbred postpartum cows (n = 351) were assigned to one of two breeding systems. Approximately two-thirds of the cows (n = 251) were subjected to an estrus synchronization protocol suitable for a fixed-time insemination (SYNC). Estrus was synchronized using the CO-Synch estrus synchronization protocol. In short, cows were administered gonadotropin-releasing hormone (GnRH; 100 ug; Cystorelin®, Merial) and 7 days later were administered 25 mg of prostaglandin F2? (PG; Lutalyse®, Pharmacia & UpJohn, Kalamazoo, MI). Cows were administered a second injection of GnRH and were artificially inseminated 48 hours after PG. Ten days later, cows were exposed to natural service for 50 days. Bull-to-cow ratio was 1:50 females in the SYNC group. The remaining cows (n = 100) were exposed to natural service for 60 days (NAT). The bull-to-cow ratio in the NAT treatment was 1:25. The bull-to-cow ratio was different between the SYNC and NAT groups because we anticipated that approximately one-half of the cows in the SYNC group would conceive to AI. To verify date of conception, pregnancy was diagnosed using transrectal ultrasonography.
To determine return on investment, all costs associated with the estrus synchronization and AI were recorded and are summarized in Table 1. Labor was determined by recording amount of time required to bring the cattle to the corral, work the cows and then return them to the breeding pastures. Four laborers were used, three trips through the chute, and an hourly wage of $7.00 per hour. To determine differences in revenue, calves were weighed at weaning and the differences in weight available to market were determined. Calves from both treatments were given a value of $1.35 per pound.
The results of this trial are shown in Table 2. More cows calved in the SYNC group than in the NAT group and more cows calved in the first 30 days of the calving season in the SYNC versus the NAT treatment. The average date of calving was earlier in the cows in SYNC than in the NAT group. The average weaning weight of calves was heavier from cows in the SYNC than from those in the NAT group. The increase in percent calf crop weaned and weaning weight increased the pounds of calf weaned per cow exposed by nearly 110 pounds.
Return on investment is shown in Table 3. Using market prices from November 2011, revenue increased by $169.41 in the SYNC group. This increased revenue was achieved by investing $29.88 per cow. Therefore the return on investment for the estrus synchronization and AI was $139.53. This return does not include savings associated with reduced bull costs. One-half the number of bulls was used per cow in SYNC group than in the NAT group. If savings on bull purchases are included, the return on investment increases to $199 per cow.
So, using ESAI in a breeding program appears to increase returns by increasing the percent of cows that wean a calf and by increasing the weaning weight of calves. Obviously, every producer cannot expect a 9% increase in weaning rate and a 73 pound increase in weaning weight. Even if using ESAI increases your cost per pregnancy by $30, in today's market, a producer would only need to increase productivity by a total of 22 pounds per weaned calf simply to break even. Only 22 pounds! Perhaps ESAI doesn't cost as much money as it makes!
Source: Dr. Les Anderson, Beef Extension Specialist, University of Kentucky