Breeding an Egg-Laying Poultry Strain Adapted to Puerto Rican Conditions

Abstract

In 1941 the Puerto Rico Agricultural Experiment Station initiated a project for the development by breeding of an adapted egg-producing poultry strain for Puerto Rico. It was assumed that the Native stock was well adapted to the detrimental environmental stresses present under tropical and subtropical conditions. This Native stock was used, together with birds of the New Hampshire, White Leghorn, and later, Rhode Island breeds as foundation material for crosses. The purebreed Native and White Leghorn stocks were later on culled from the flock and, by 1955, the surviving lines were: 1, The New Hampshire; 2, a cross of the New Hampshire with the White Leghorn backcrossed to the New Hampshire; 3, a 60-percent White Leghorn-40-percent Native cross; 4, the Rhode Island; and 5, a cross between the Rhode Island and the New Hampshire. A comparative evaluation of the existing lines showed the Rhode Island- New Hampshire cross to be superior to the others in most of the productive characters. However, a comparison of the project lines with imported commercial hybrids failed to show significant differences in their performance. It was found during this work that the contribution of the Native stock towards the project's objective would be negligible, and that economically feasible improvement in management conditions could offset most of the detrimental environmental stresses, so that high-producing imported hybrids could be used commercially in the Island. It was concluded that, whenever the man-made conditions can be economically improved, this offers a better possibility than breeding for adaptability for increasing livestock production in tropical and subtropical areas.