Analysis of poultry fertility data

Abstract

Single Comb White Leghorn (SCWL) hens were inseminated intravaginally with spermatozoa from either SCWL or subfertile Delaware roosters in three replicate fertility trials. Overall fertility was analyzed with a log odds model following logit transformation. Duration of fertility was analyzed by iterative least squares. Hens inseminated with spermatozoa from SCWL males laid a higher proportion of fertilized eggs over a longer interval than those inseminated with spermatozoa from affected Delawares. Log-odds and logistic models may have advantages over the more traditional methods of evaluation. This is particularly true in regard to the distribution and normalization of error variances via the logit transformation and removal of nonadditivity via logistic regression.