Studies on the Effect of Vitamin B<sub>12</sub> on the Growth Rate, Egg Production and Hatchability

Abstract

The two experiments were carried out to study the effect of vitamin B12 on the growth rate of chick, and the egg production and the hatchability of laying hen.(1) White leghorn hens were fed either low vitamin B12 layer diet, which consists of corn starch, meal and soybean oil, or high vitamin B12 layer diet, which was enriched with 10μ of vitamiu B12 per kg of the low vitamin B12 layer diet.The efficiency of vitamin B12 had no influence on egg production, egg weight, feed consumption and viability of the hens. Moreover, no difference in hatchability was observed between the fertile eggs of hens on low vitamin B12 diet and that on high vitamin B12 diet, although vitamin B12 content in the former was much low than that in the latter.(2) The additional effect of vitamin B12 (10μg/kg) and DL-methionine (0.4%) to the low vitamin B12 and low methionine starter diet was examined on the growth rate of the chicks, which were offsprings of breeding hens fed either low vitamin B12 layer diet or high vitamin B12 layer diet.Additional vitamin B12 to both of low vitamin B12 layer and starter diets was effective to improve growth rate of the chicks. The additional effect of methionine on the chick growth was significant, although the interaction between vitamin B12 and methionine on the growth rate of chick was not recognized. The feed conversion was improved by addition of either vitamin B12 or methionine to low vitamin B12, low methionine starter diet. Possitive correlation was observed between the amount of vitamin B12 in the chick liver and growth rate of chick.