Influence of vitamin B-6 upon reproduction and upon plasma and egg cholesterol in chickens.

Vitamin B-6 deficiency in the laying hen causes an immediate anorexia, loss of body weight, greatly reduced body fat stores and severe effects upon primary and secondary sex characteristics resulting in severely reduced hatchability culminating in complete cessation of egg production. While inanition may have been largely responsible for involution of the ovaries and oviducts in the vitamin B-6 deficient hens, regression of combs and wattles appears to be a more specific sign of vitamin B-6 deficiency. Serum cholesterol levels of vitamin B-6-deficient hens were lower than those of hens receiving an adequate diet. Egg cholesterol values remained relatively constant regardless of dietary B-6 levels or of alterations in serum cholesterol. No ataxia or mortality was observed in vitamin B-6-deficient hens or roosters. The effects of vitamin B-6 deficiency were almost completely reversed upon repletion of the hens with adequate dietary vitamin B-6.