[Artificial rearing of double purpose calves of the beef-dairy type. 1. Effects of the length of the milk-rearing period and of the amount of milk substitutes needed for the rearing of the calf].

Reducing the period of Milk rearing of calves from 90 days (time of weaning) as practised today to 50 days or 70 days (and thus reducing the amount of regenerated milk which is needed to rear the calf from 400 litres to 200 litres or 300 litres) would limit the rate of weight gains of the calves in the first 3 months of age. This delay is, within certain limits, compensated for by the calf in the growth period up to 6 months of age. Therefore, the authors believe that with cattle of the Hungarian breed "Ungarische Fleckviehrasse" weaning after 50 days and rearing the calves with 200 litres of milk seems to be possible. The method of early weaning and then feeding stock mixtures of concentrates seems to be also applicable provided that the conditions of veterinary hygiene would allow this. This, in turn, would require supplementation of the food with minerals and vitamins. Due to the results obtained supplementation of concentrate mixtures with urea for calf rearing is also possible, even under practical conditions. Aromatization of the concentrate mixtures, as practised in the present series of trials, did not substantiate the favourable results obtained by the authors in previous trials with respect to the effect of aromatics on food consumption and the development of weight gains.