EN
The process of development in horses could be divided into three phases: foetal, nursing and maturation. It has been demonstrated that the maternal effect is the greatest during pregnancy. The bigger the placenta, the heavier the foetus and newborn foal. During the nursing period the intensity of growth is genetically dependent. The foals that were small at birth grow more rapidly. Increased feeding results in weight gain but does not accelerate growth rate. The process is continued during maturation. However, irrespective of the intensity of growth, the foals, which were small at birth are not able to compensate for losses in the foetal phase. The offspring, which had suitable nutritional and growing conditions in the foetal phase become taller and have longer long bones in the limbs when mature.