Abstract:
The high prices of available supplies of cereals like maize, barley, and oats has aroused considerable interest in stepping up the use of unconventional energy and protein feed sources to reduce the costs (costs of feed and total production costs) and improve the efficiency of small-scale poultry units. Dried Bakery products (DBP), is one of these unconventional ingredients produced in large quantities in South Africa, which is available for animal feeding. The aim of this study was to determine the cost effectiveness of the use of DBP with commercial rations, using the choice feeding method, without compromising performance of broilers produced in small-scale commercial poultry enterprise. A total of five hundred and seventy day-old-male broiler chicks (Ross), were assigned to three feeding treatments of 190 birds each over a period of 42 days. All the birds, in all three groups, were given a complete diet (starter mash) the first seven days. Treatment A (TA) was fed as a two stage (starter and grower ration) complete diet and acted as a control. Besides DBP acting as a substitute energy source, salt (NaCl) concentration (being a limiting factor in broiler rations) was also considered as a target for selection. Treatment B (TB) was given a starter ration up to day seven, thereafter, receiving simultaneous access to a complete diet containing a normal salt percentage and DBP. Treatment C (TC) was given starter ration to day seven, thereafter receiving simultaneous access to a complete diet containing a low salt percentage and DBP. The performance of birds was measured in terms of feed intake, weight gains, feed conversion rate and mortality. In addition, an economic evaluation (cost analysis, net profit, total physical product (TPP), average physical product (APP), marginal physical product (MPP) calculations and gross margin analysis) was done. DBP was also analysed for its nutrient composition, as well as tested for aflatoxin. The use of DBP in groups TB and TC resulted in a reduction of the feed costs by nearly a third and consequently had a positive impact on the total cost of production, net profit and gross margin analysis per live bird and per kg of live birds in contrast to the control group (TA). The TPP, APP and MPP calculations revealed that the use of DBP was beneficial during the entire production period since the value of the marginal product remained higher than the cost of DBP. This study has also confirmed that chickens are able to self-select their diets when raised under choice situations. This is shown by the performance of birds in terms of body weight, feed intake feed conversion, mortality and necropsy results. Groups TB and TC had similar body weights, feed intake, mortality % and feed conversion. The feed conversion was slightly ( but not significantly), higher for TB and TC than for TA. This suggests that the conversion of DBP into kg live weight of chickens in groups TB and TC, was at least as efficient as the control diet (TA). It can be concluded from the results, that DBP can be safely used as a viable alternative energy feed source in a small-scale broiler production system. The higher salt content of DBP did not play a significant role in choice of ration by the birds (TB and TC were not significantly different). The use of the choice feeding method was successful and showed that it was a practical alternative to computer formulation of rations, as it allows the birds to ingest a percentage of DBP in the ration to meet their growth requirements. The use of DBP and starter ration on a choice feeding system (TB and TC) rather than starter and grower ration in a two-stage system (TA) resulted in increased productivity and profitability.