Senwes Scenario February / March 2019 | Page 16

AGRICULTURAL Use of GROWTH PROMOTANTS in Feedlot Cattle What are the advantages and risks involved? The profitability of a feedlot is mainly determined by the productivity in cattle production. This can be extrapolated to the whole feedlot industry which also faces perceptually environmental implications by the public.  By Dr Kobus Swart Animal Nutrition Specialist T he cost of buying a calf and the feed needed to finish it are the two largest variable expenses facing a beef feedlot. These two costs are also external prices imposed on the feedlot which increases the risk substantially. To survive under these cir- cumstances careful and well-informed decisions must be taken and where even a ‘mind-shift’ must be applied . Growth Promotants are among the many sophisticated tools metabolic 14 technology used by feedlots and other producers worldwide to raise more beef, more rapidly, using less feed, while main- taining high standards of animal health, carcass quality and food safety. The three main products approved and used in the feedlot industry are antimicrobials in the form of ionophores, hormonal growth implants and Beta adrenergic agonists. WHAT ARE THE BENEFITS OF METABOLIC TECHNOLOGY? The best way of measuring the benefits of growth promotants are the average daily live mass gain over a period and the rate of feed conversion to live mass (FCR). SENWES SCENARIO | MIND-SHIFT 2019 Both the circumstances and the quality of feed must be specified to be able to compare these measurements accurately. Ionophores, implants and beta-agonists improve daily gain typically on average with 3%, 16% and 16% respectively. Feed efficiency is improved by the same promotants by 4%, 10% and 14% respec- tively. The feedlot production costs would be at least 10% higher if producers decide not to or were unable to use ionophores, implants of beta-agonists. It is calculated that the benefits of the growth promotants allow a feedlot or industry as a whole to produce 10% more beef with 20%