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R. B. Nestler

Publications and source records attributed to R. B. Nestler.

At least 19 recordsLinked to original sources
USGS1949

Calcium and phosphorus requirements of breeding bobwhite quail

In the course of studies designed to determine the calcium and phosphorus requirements of breeding bobwhite quail, it was found that best results were obtained when the Ca/P ratio in the diet was approximately 2.3:1. Variations in the Ca/P ratio produced significant differences in results when the level of phosphorus in the diet was 0.75%, but the differences were less marked when the level of phosphorus was increased to 1.00%. Although diets containing 0.75% phosphorus and 1.8% calcium appeared adequate for reproduction, as judged by the criteria of the maintenance of satisfactory condition in the breeders, egg production, fertility, hatchability and survival of offspring during the first 5 days after hatching, it was found that the winter mortality of the offspring of birds fed such a diet was much greater than that occurring in the offspring of birds fed on diets containing 1.00 or 1.25% phosphorus. It is concluded that breeding bobwhite quail require diets furnishing approximately 1.00% phosphorus and 2.3% calcium.

Journal of Nutrition↗
USGS1948

Storage by bobwhite quail of vitamin A fed in various forms

According to studies conducted with 236 bobwhite quail chicks at Patuxent Research Refuge, crystalline carotene in cottonseed oil fed at levels of 3000 I.U. (the requirement for optimum growth), 5000 I.U., and 25,000 I.U. per pound of feed, was utilized only ⅓ to 1/7 as efficiently as vitamin A alcohol; ½; to 1/10 as natural vitamin A ester; and ¼ to 1/17 as vitamin A acetate, based on the storage of vitamin A in the liver. The carotene in the natural carrier, alfalfa leaf meal, was assimilated as effectively as was crystalline carotene in cottonseed oil, when both were fed at 5000 I.U. per pound of feed. Crystalline carotene when fed at a level over 8 times the requirement of the quail for maximum growth, or 25,000 I.U. per pound of feed, was stored as vitamin A in the livers of pen-reared quail to an extent comparable to the levels found in certain young wild quail. Vitamin A acetate was utilized more efficiently by quail than either vitamin A alcohol or the natural vitamin A ester. There was considerable individual variation in storage of vitamin A by quail on the same diet, and with the same or similar parental background.

Journal of Nutrition↗
USGS1945

Inbreeding among pen-reared quail

The effect of inbreeding in wildlife species has received attention from several sources. Recently the 'inbreeding theory' as a possible explanation of cycles in game populations was given careful consideration by a group of wildlife experts and geneticists. Scott's symposium (1944) consisting of comments received from eight authorities revealed unanimity in a decision that inbreeding is not the causative factor.

The Auk↗