Did you know that seedstock breeders in the double-muscled Piedmontese breed routinely measure the pelvic capacity of yearling heifers, to identify those more likely able to have a calf unassisted? They do this with ultrasound.
Those with insufficient pelvic capacity go straight into their feedlots. In their case, culling becomes a valuable selection tool (to improve a trait for which the breed was originally criticized) while maintaining the premium carcass value of their breed. As for the heifers culled from breeding and going to feeding, the premium carcass value recovers the rearing cost (better than would be true for most conventionally bred cattle). Heifers in virtually all beef breeds are able to reach a “finish” condition faster than bulls, given they have passed through puberty.
Ultrasound for early pregnancy diagnosis.
More
established veterinary services now have “ultrasound” equipment primarily for
use when asked to examine cows for pregnancy. Compared to palpation, ultrasound offers
advantages such as: (1) earlier PG confirmation with less risk of
“therapeutic” abortion.
(2) electrovisual confirmation of calf sex
(3) potential identification of fetal
abnormalities
(4) confirmation of breeding dates
For most of us, especially as herds get larger, the breeding season comprises a couple rounds of AI services with pre-selected planned matings to desired sires, followed by turning in “cleanup” bulls we either bought (at a bull test, or from a trusted breeder) OR raised (from better fertility record “momma cows”). For next-season marketing plans, we might wish to know which cows got bred AI vs which cows waited for “barnyard barney”. This is an area where “ultrasound” is more precise than manual palpation.
Palpation skill is still necessary for successful Ultrasound.
If you have not learned how to AI your cows, you should not be thinking (much) about buying “ultrasound” equipment, which in our research costs $3500 to $7000 from most vendors just for the hardware (hands-on training mostly not included). While you may find the veterinary service charges are larger than they used to be, you would be hiring someone with enhanced skills in this area.
The downside to “ultrasound” vet training is that they tend to lose the skills needed for manual palpation diagnosis. Plus there might be over-reliance on the technology encouraging earlier pregnancy confirmation, which might miss those pregnancies that fail to complete transition from the “embryonic division” stages to the “fetal attachment” stage, a process that takes six to eight weeks. Based on some data from twenty years ago in large Michigan dairy herds, 5% of all cows diagnosed as pregnant prior to 60 days post-breeding end up open after 60 days … No calf in cow equals no income from cow for an entire season!
Utilizing technology in breeding
Ultrasound is popular, especially as fewer large animal vet students graduate from our land-grant universities. Those with good herdsmanship skills and larger herds may have acquired ultrasound equipment, but ultrasound services are available at most established veterinary practices.
As long as we remember some of the basics of mammalian reproduction (a lot of pregnancies start, not all make it to full term) and stay focused on the goal every cow we breed gets pregnant in time and delivers a live calf we can make decisions on how much (and when) modern technology applies, and when we should stick to traditionally successful husbandry techniques.
In the pursuit of ever-higher animal performance, it pays to keep our cow genetic selection in favor of natural fertility and maternal instinct, so that we do not lose ground on basic cow-calf economics: “No calf, no income …”
MIch Livestock Service, Inc “For the Best in Bulls” and “Better forages for efficient feeding”
No comments:
Post a Comment