Serum progesterone, enzymes, and electrolytes of hens laying a low or high incidence of shell-less eggs.

Three experiments were conducted to determine possible differences in serum progesterone, enzymes, and electrolytes between hens laying a high or low incidence of shell-less (SL) eggs. Blood was taken at time of oviposition and at 6, 12, 18, and 25 hr later, irrespective of the stage of the sequence. The results indicated no significant differences in average serum progesterone between hens laying a high or low incidence of SL eggs. In general, the patterns of serum progesterone in relation to time of oviposition was similar for each type. No significant differences were observed in serum phosphorus, magnesium, glutamate pyruvate transaminase, or alkaline phosphatase between hens laying a high or low incidence of SL eggs. It was concluded that the production of SL eggs is not related to abnormal serum progesterone, alkaline phosphatase, glutamate pyruvate transaminase, magnesium, or phosphorus levels.