Environmental influence on the egg size of pullets in Puerto Rico

Abstract

The curve of the egg size (in ounces per dozen eggs) for the first laying year was studied in a group of 206 pullets of different breeds and crossbreds. Regression studies were made of the average monthly egg size. The early-maturing pullets started by laying smaller eggs than the late-maturing pullets. The observations made on the curves of the egg size seems to agree with the findings of Warren et al (9) in respect to the depressive effect of high temperature on egg weight. Egg size increased progressively during the first months of laying, reaching a maximum from May to June. The high summer temperatures caused it to decrease rapidly toward the end of the laying year.