Paternal influences on turkey embryonic growth in the absence of changes in egg weight and eggshell conductance

The hypothesis was proposed that embryonic growth could be influenced pater nally in the absence of changes in egg weight or eggshell conductance. Sire families were established by selecting 11 sires based on blood sampling of approximately 50 commercial turkey males. Southern blot analysis was used to identify the most distantly related individuals in the subpopulation. Fi ve hen siblings or half-siblings of the males were randomly assigned to eac h male to randomize effects of egg size and eggshell conductance. Artificia l inseminations were performed weekly for 17 wk, using each sire with the a ssigned hens. Fertilized eggs were collected and set in incubators at biwee kly intervals. Offspring were observed at the time of hatching for sex, bod y weight, and blood glucose concentration. Significant differences among si res were observed at hatching for poult weights and blood glucose concentra tion, and a significant correlation between the BW and glucose concentratio n was noted. Progeny of sires with the highest and lowest BW and blood gluc ose concentrations were subsequently compared. Mean BW of poults from diffe rent sires differed by as much as 10 g, although they were hatched from egg s of the same weight. Elevated blood glucose was associated with heavier BW ; heavier heart, liver, and muscle weights; a rapid utilization of glycogen at pipping; and increased gluconeogenesis as measured by plasma organic ac ids and glucose-6-phosphatase activity. We conclude that poult embryonic gr owth differs even when not mediated by egg size and functional characterist ics.