Vitamin B12 in the Nutrition of the Laying Hen

INCREASING evidence is becoming available which indicates that vitamin B12 plays an important role in the performance of laying and breeding hens. That vitamin B12 is necessary for hatchability has been shown by Lillie et al. (1949), Lindstrom et al. (1949), Olcese, Couch and Lyman (1950), Couch and co-workers (1950), and Carver and McGinnis (1950). The level of vitamin B12 required for hatchability has been estimated at 1 mcg. per pound of feed by Norris (1950). An indication that vitamin B12 may be required for egg production has been presented by Olcese et al. (1950), and Couch and co-workers (1950). Stevens and co-workers (1949), McGinnis et al. (1948), and Charkey and associates (1950) have shown that vitamin B12 is involved, not only in the growth of chicks, but also in efficiency of feed utilization. Stevens et al. found that an addition of vitamin B12 to a growing ration resulted in . . .