[Joint research on the precise determination of the energy and protein requirements of fattening pigs. 4. The effect of the energy level on the fattening of Camborough-type hybrid swine].

Scientific feeding experiments were carried out with 5 castrated male pigs and 4 female animals of the genetic origin "Camborough" in the live weight range between 30 and 100 kg with a subdivision at 60 kg. In each test group the animals were fed individually and received rations with approximately equal contents of protein, amino acids, minerals and vitamins but different energy contents. Energy intake was adjusted to 3 levels of 100%, 85% and 70% of semi-ad-libitum intake. Apart from that, the digestibility of the feed mixtures used in the 2 fattening periods was determined. Having reached a live weight of 100 kg, 7 representative animals per group were slaughtered and a number of slaughtering parameters were registered. In all three test groups the daily live weight gain over the complete fattening period was very high (846, 819 and 778 g). Though the weight gain in group 3 with 70% of the energy supply of group 1 is significantly lower than in the other two groups, it is, however, only 70 g lower than in group 1. Consequently, the feed expenditure (2.6 kg mixed feed per kg live weight gain) in group 3 is by 20% lower than in group 1, in which the feed expenditure is 3.2 kg mixed feed per kg live weight gain. There were no significant differences on the weight gain performances and the registered carcass parameters between sows and castrated male pigs. Observed deviating tendencies are discussed.(ABSTRACT TRUNCATED AT 250 WORDS)