Influence of hen dietary calcium and phosphorus on the integrity of the egg shell as it would influence hatching success and the consequences of preincubation 2, 4, 5-T spraying with and without a high TCDD level.

Commercial strain laying hens were fed practical rations deficient in calcium and/or phosphorus to affect weak shelled eggs. Spraying these eggs prior to incubation with 2, 4, 5-T preparations having extremes in TCDD contamination at 10x recommendation was without effect on all parameters used to evaluate embryological development and subsequent early performance of resultant chicks. Analyses for 2, 4, 5-T residues indicated that the shell though weakened was unaffected as a barrier to herbicide contamination.