Whether times are tight or not, each percentage point increase in pregnancy rate returns $15 to $18/cow/year. Even herds cruising along at 18% stand to gain $30 to $35/cow/year by bumping the rate to 20%. In a 500-cow herd, that translates to $15,000 more income net expenses.
Neil Michael, director of technical services for ABS Global, says many herds consistently achieve pregnancy rates of 20% to 25%, with many commercial dairies already exceeding 35% to 40%. He lists eight influencers of reproductive success that every dairy should monitor:
1. Postpartum health effects. Poor transition periods can influence the incidence of retained placenta, DAs, metritis and mastitis, all of which can delay conception.
Monitor: Dry matter intake, stocking density, manure scores, cud chewing, postfresh body condition change and milk production during early lactation.
2. Insemination risk. "Accurately getting semen into eligible animals is the largest opportunity to improve preg rate on most commercial dairies today,” Michael says.
Monitor: Percent bred, plus or minus your target voluntary waiting period for 90 days previous. Work for less than 2%.
3. Technician performance. Some AI technicians are simply more skilled than others.
Monitor: Technician conception rate and accuracy using blood progesterone. Avoid bias from season of year, lactation number and service number.
4. Cow activity. High-producing cows need 12 to 14 hours/day of comfortable lying time. "Extended time on feet is one of the largest limiting factors to high production, reproduction
and long-lived cows,” Michael says.
Monitor: Stall use index, turn times to/from parlor, lockup time, locomotion scores and stocking density.
5. Synchronization efficiency. The current recommendation is not to inseminate before 70 to 80 days in milk for timed insemination programs.
Monitor: Synch efficiency, by using blood progesterone testing on 20-plus cows at the time of timed AI and on the same cows seven to 14 days after insemination. Goal: 90% or greater for synch efficiency and cyclicity.
6. Re-enrollment of open animals. "Resynch programs that ensure all open animals found on herd check are reinseminated with 10 days are optimal,” Michael says.
Monitor: Days to rebreeding for all cows found open on herd check for the last 30 to 60 days. Reconfirm pregnancy 100 to 120 days carried calf.
7. Heat stress. Holding pens are a major contributor to heat stress loads.
Monitor: Holding pen temperatures with data loggers to assure cooling is effective. Also provide clean, high-quality water in pens and exit lanes.
8. Insemination type. On most dairies, semen is placed based on various factors that should be recorded: natural heat detection, chalk, timed AI, requested, dirty, blood and so on.
Monitor: Conception rates by insemination type—a minimum of 250 to 300 tests of each type to achieve meaningful statistical differences.
Improving Reproductive Performance on Commercial Dairies