This experiment compared fertility of male broiler breeders with different crude protein (CP) intakes from diets containing 9.7%, 11.7% and 13% CP from 27 to 60 weeks of age (in two phases) and in a different group of birds from 52 to 60 weeks of age. This was to assess fertility of males with different CP intakes, as well as comparing fertility in older birds having been fed different protein intakes throughout production to those on a commercial ration for most of production. Sperm concentration and sperm mobility were assessed, as well as the number of points of hydrolysis in the inner-perivitelline membrane of eggs from commercial egg-type hybrids after insemination, which was used to predict egg fertility. There was no response to CP intake observed in sperm concentration or sperm mobility at any age. A positive effect of CP intake was observed in egg fertility towards the end of the production phase. While broiler breeder producers make use of separate sex feeding, the female ration is often fed to males in the appropriate amounts to achieve growth according to the target for males. However because it would be cheaper to include less CP in the ration, the effect of CP on breeder fertility is important. This experiment showed that reducing CP to 117 g/kg in male broiler breeder rations fed throughout the production phase had minimal negative effects on sperm quality, however, increasing CP intake towards the end of production may positively impact egg fertility.
"Experientia docet" - Experience is the best teacher