Pantothenic Acid in the Nutrition of the Hen

Abstract

Studies have been made of the pantothenic acid requirement of hens fed a diet of purified ingredients supplemented with 4% of fish meal. Under these conditions, the requirement for maximum hatchability was found to vary somewhat, depending on the degree to which the hens were selected for hatchability. In 1 experiment, the requirement for hatchability was found to lie between 750 and 1000 µg of pantothenic acid per 100 gm of diet. In a second experiment although 650 µg supported optimum hatchability, it was found that at least 800 µg per 100 gm was necessary in the diet of the hens to promote best growth, and to prevent symptoms of deficiency and mortality in their progeny. It appears from the lower requirement obtained with the purified diet, that a deficiency in the heated diet previously used considerably increased the requirement for pantothenic acid. When hens depleted of pantothenic acid were supplied this vitamin, hatchability of their eggs returned to normal in 1 or 2 weeks. Embryonic mortality due to pantothenic acid deficiency was found to be confined almost entirely to the last 2 or 3 days of the incubation period. The deficiency did not result in deformities in the embryos. Chicks hatched from hens receiving suboptimal levels of pantothenic acid were generally inferior, however. Egg production and maintenance of weight were not adversely affected during a 10-week period by a pantothenic acid level as low as 150 µg per 100 gm of diet. Hens maintained for 10 weeks on a diet containing this amount of pantothenic acid actually increased their body weight during 2 different experiments, and in 1 instance increased the rate of egg production. The pantothenic acid content of the diet is quickly reflected in the amount of this factor found in the blood and eggs. The amount stored in eggs was found to fit the same straight-line equation for all dietary levels studied. The amount of pantothenic acid in the blood is much lower than that for eggs, and tends to remain constant below 350 µg per 100 gm of diet, or above 1100 µg. The minimum pantothenic acid content of whole blood associated with optimum reproductive performance was 0.45 µg per milliliter. For eggs, the corresponding value was 9.5 µg per gram of whole egg.