| Autor: |
Kuhlers, Daryl L., Jungst, Steve B., Edwards, Ronnie L., Little, J. A. |
| Zdroj: |
Journal of Animal Science; July 1981, Vol. 53 Issue: 1 p40-48, 9p |
| Abstrakt: |
Specific crosses resulting in 305 litters sired by Duroc, Spot or Hampshire boars out of Landrace, Duroc - Landrace or Yorkshire-Landrace sows were evaluated for preweaning and postweaning performance. Duroc-sired litters were heavier (P<.05) at 21 days post-farrowing than Spot- or Hampshire-sired litters. Hampshire-sired litters were heavier (P<.05) at birth than Spot-sired litters. Litters from crossbred sows were larger in number (P<.05) and heavier at 21 (P<.01) and 42 days (P<.05) than those from Landrace sows. However, survival rate to weaning did not differ significantly between the litters from crossbred and from purebred females. There were no significant differences in litter size between Duroc-Landrace and Yorkshire-Landrace sows. However, pigs out of Duroc-Landrace sows were heavier (P<.01) at birth than pigs out of Yorkshire-Landrace sows. The interactions of the Spot and Hampshire sire breeds with the Landrace and crossbred Landrace dam breeds were significant for litter size at 21 and 42 days and for survival rate. A change in the rankings for these traits was noted. Pig weights at 21 and 42 days showed the same interaction. Maximum preweaning performance resulted from the mating of Duroc boars to Duroc-Landrace or Yorkshire-Landrace sows or of Hampshire boars to Duroc-Landrace sows. No significant differences among the sire breeds were noted in progeny postweaning daily gain or days to 100 kilograms. Pigs out of Duroc-Landrace sows had higher postweaning gains (P<.10) and higher (P<.01) average daily gains during the test period than pigs out of Yorkshire-Landrace sows. Pigs sired by Duroc boars were more efficient (P<,01) at converting feed to gain than pigs sired by Hampshire and Spot boars. Pigs out of Duroc-Landrace and Yorkshire-Landrace sows were more efficient (P<.01) at converting feed than those of the Landrace sows. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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