Die Bodenkultur - Journal for Land Management, Food and Environment
K. Gritzer and R. Leitgeb:
Evaluation of the effectiveness of antibiotic and probiotic growth promoters on the performance of fattening bulls
In a feeding experiment with 72 Simmental bulls the effect of one antibiotic growth promotor Monensin-Na (MON) and two probiotics (Cylactin LBC SF68 (LBC) and Bacillus Toyoi (TOY)) on the growing and slaughtering performance were compared to a control group (KG). The animals were randomly allocated to 4 groups of 18 animals each.
The bulls were grown from 120 to 630 kg body weight. The ration consisted of maize-silage (37 % DM) ad libitum and protein concentrate 1.43 kg/d (35 % protein), The analysed daily dosage per head of MON was 195, of LBC 110 and of TOY49 mg. The average daily weight gain was as follows: MON 1292 >TOY1272 >LBC1266 > KG1245 g.
Total daily dry matter intake (DMI) was between 6.8 and 6.9kg. The energy efficiency (MJME/kg W) was as follows: MON 47.6 < LBC, TOY 48.4 < KG 49.6. Daily gain, DMI and energy efficiency were not significantly affected by the growth promotors. The fatty acid pattern of pelvic fat was influenced by MON in the diet. The slaughter weight, carcass dressing and the parameters of meat quality (tenderness, juiciness and taste) showed no significant differences between the groups. From the results, it may by concluded that MON, LBC and TOY had a slightly positive effect on the growth performance.
Key words: Bull-fattening, growth promotors, antibiotics, probiotics.