Die gebruik van Mamalvite en Flavomisien in die grootmaak van suiwelkalwers
South Africa produces only 0,50 % of the world’s milk. Although the number of milk producers is decreasing in South Africa, the milk production per se is increasing. The total number of small producers is decreasing while the number of big producers is increasing. The cost to raise replacement heifers is very high. Replacement heifers are the cows of tomorrow and should be seen as a valuable investment for the longterm survival and profitability of the dairy farm. A successful heifer rearing program is one in which: • Heifers are economically raised to be of adequate size and body condition to calve at a reasonable age. • Heifers produce high levels of milk during the first lactation. In the current study, the effect of Flavomycin and Mamalvite supplementation to young calves was investigated. According to manufacturer’s claims, Flavomycin would result in improved gains, improved conception rates, shorter calving intervals, increased milk production and improved weaning weights. Mamalvite, according to the manufacturer, should reduce risk of infections, increase feed utilization, increase feed intake and production, and also increase rumen microbial efficiency. Thirty two Holstein calves, four days of age, were randomly divided into four groups of eight. All calves received 4 kg whole milk daily and had free access to calf starter pellets. Treatments were: 30 ml Mamalvite daily supplemented in the milk and 5 g Flavomycin daily per os (Treatment 1), 30 ml Mamalvite daily supplemented in the milk (Treatment 2), 5 g Flavomycin daily per os (Treatment 3) and a control group that received milk only (Treatment 4). All the calves were weighed weekly. According to the results obtained in the current study, neither Flavomycin, nor Mamalvite, nor a combination of the two resulted in an improvement in calf weight gains. It was concluded that it does not appear to be an economically viable option to supplement Mamalvite or Flavomycin to calves that are reared in a well managed environment.