Change in myoglobin content in rabbit and chicken muscles in ontogenesis.

The accumulation of myoglobin in the muscles was studied in the ontogenesis of rabbits and chickens. A connection was found between the myoglobin content and the degree of the functional load of the muscles in different age periods. Myoglobin appears first in the myocardium. In the femoral muscles of chick embryos myoglobin is first found on the 16th day of incubation. Myoglobin is not detected quantitatively in the masseter and femoral muscles of the rabbit during prenatal development. The myoglobin content is highest in the gizzard of a mature hen.