WASHINGTON, D.C. – Research financed by the U.S. National Pork Producers Council shows bred sows injected with porcine somatotropin may have larger litters with bigger muscled piglets.
The research team reported it could mean several benefits for hog producers:
- Increased litter number and weights of pigs weaned.
- Lower embryonic mortality rates by possibly increasing uterine capacity, thereby further increasing litter size.
- Improved growth performance of offspring due to altered carcass composition.
- Increased carcass and product value through less need to trim carcasses.
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“An increase of one pig per litter could mean more than $50 per litter,” the council reported recently in its Pork Leader newsletter.
In the project, 75 uniform gilts were mated to boars with contrasting genetic extremes. Half were bred to heavily muscled boars that would be expected to sire pigs with enhanced muscle mass. The other half were bred to boars with average or light muscling.
Half the gilts in each genotype group were injected twice daily with the hormone starting at day 14 of gestation. Gilts from each group were slaughtered at six time points, from 16 to 28 days of gestation, to determine the effect of the hormone treatments on embryonic survival and muscle cell development.
“Understanding the controls of muscle formation at the molecular genetic level may one day lead to precise regulation of muscularity in pigs,” the researchers said.
Increasing the value of market hogs by treating their mothers with hormones would be more efficient and less costly than attempting to treat each pig individually, as must be done in dairy cows to increase milk production.