Paternity Efficiency in Turkeys Differes Extensively After Hererospermic Insemination

All commercial turkey hens in the U.S. are bred by artificial insemination (AI). Since semen samples are pooled from 10 or more males (heterospermic inseminations), paternity of the progeny is rarely known. Whereas it is known that sperm competition exists, the degree to which any male\u27s sperm fertilizes ova relative to other male\u27s remains unknown. In this work, we determined individual male fecundity relative to that of other males in the study and attempted to establish a relationship between male fecundity and semen characteristics in turkeys. Fingerprinting of genomic DNA from parents and offspring was used to determine parentage efficiency. This work demonstrated that relatively few toms sired a high percentage of the progeny. Of the 26 toms contributing to the pooled ejaculates, six (23%) sired more than 60% of the 145 poults. Conversely, 14 toms (54%) sired three or fewer poults. We found that the semen parameters evaluated, some of which are used routinely by the turkey industry, were not good at predicting paternity. Under the conditions of this study, the majority of the projeny were derived from semen from on or two toms after heterospermic inseminations