Investigations about the influence of design, growing period, feeding rations and origin on fattening performance and slaughter value of young Simmental bulls

In a feeding experiment with 310 Simmental male cattles the question was to examine the influence of their origin (country breed versus research farm), feeding level (high - 9.11 MS ME, medium - 8.60 MJ ME and low - 8,06 MJ ME per kg dry matter - DM) as well as fattening period (365, 425 and 485 days of life (DOL)) on fattening and slaughtering performance. Bulls were fed with pelleted complete diets ad libitum. The results show, chat the origin had no significant influence on fattening performance (live weight, daily gain). Regarding feed and nutrient intake there were significant differences only with a few characteristics (dry matter consumption at the fattening period 245(th)-305(th) DOL and intake of crude protein - XP on the fattening periods 185(th)-245(th), 245(th)-305(th) as well as 305(th)-365(th) DOL). Feed conversion (DM/kg gain) and ME intake were not affected by origin. Characteristics of slaughter value on the other hand were influenced by origin (meat and Eat yield of carcasses, percentage of high priced cuts). Feeding level had a distinctive influence on the live weights of the animals, especially between the low and the high feeding level. The live weights in the high feeding level were 444.0 kg on the 365(th) DOL, 510.4 kg on the 425(th) DOL and 577.2 kg on the 485(th) DOL. Daily gain was effected by feeding Level only in the first three fattening periods. During the whole fattening period (125(th) DOL until slaughtering) the daily gains were 1095 g in the low feeding level, 1159 g in the medium feeding level and 1186 g in the high feeding level. Feeding level had no significant influence on the daily intake of dry matter (DM) and crude protein (XP), but certainly on the intake of energy (ME). With the exception of meat yield, feeding level significantly effected the characteristics of slaughtering performance (slaughter weight, dressing percentage, net gains etc.). The value of fat percentage in the low feeding level was 7.13 %, in the medium feeding level 7.48 % and in the high feeding level 7.83 %. Net gains were 643 g, 679 g and 706 g, respectively. Fattening period effected fattening performance and carcass composition. Fattening period increased average daily feed intake as well as feed conversion. Energy utilisation (ME) per kg gain was 70.55 MJ (365(th) DOL), 74.49 MJ (425(th) DOL) and 64.08 MJ(485(th) DOL). Daily gains differed significantly between 365(th) DOL (1166 g) and 485th DOL (1123 g). Net gains did not depend on fattening period. All other recorded characteristics of slaughter value were certainly effected by fattening period. Meat yield was 73.47 % (365(th) DOL), 73.75 % (425(th) DOL) and 74.22 % (485(th) DOL). Fat proportion increased from 7.21 % (365(th) DOL) up to 7.48 % (425th DOL) and 7.75 % (485(th) DOL). With the exception of the proportion of valuable cuts no further interactions between the main effects could be proofed.