Awassi lamb growth responses and carcass traits, and economic benefits associated with reduced-cost diets made from locally available feed resources

Abstract

Awassi lamb-fattening systems in Middle Eastern countries are popular because they can rapidly generate income. Nevertheless, feed costs constraining these systems and seasonal fluctuations in feed prices expose farmers to risk. A 90-day fattening experiment was conducted at the International Center for Agricultural Research in the Dry Areas (ICARDA), in Syria, to compare reduced-cost diets that use locally available feeds with the diet used traditionally by farmers. Thirty-six 4-month-old Awassi lambs (mean live weight 23.0 kg) were randomly assigned to three groups: (1) the control group (C), in which lambs were provided with the diet used in fattening systems in Syria; (2) the faba bean and beet molasses group (FBM), in which the lambs were fed a reduced-cost diet in which the barley given in C was replaced with faba bean and beet molasses; and (3) the wheat bran and beet molasses group (MM) replacing a large portion of the broken maize and a small portion of the barley in C. Lambs in C and the reduced-cost diets (FBM and MM) had ad libitum access to untreated (UNTWS) and urea-treated wheat straw (UTWS), respectively. An 11-day digestibility trial was conducted in a subset of the fattened lambs at the end of the growth phase. Total weight gains (24.7, 25.5 and 26.2 kg in groups C, FBM and MM, respectively) and average daily gains (0.282, 0.298 and 0.291 kg/day for C, FBM and MM, respectively) did not differ between groups (P > 0.05). The FBM and MM alternative diets were 13.5% and 11.8% less expensive, respectively, than the C diet. However, due to the higher dry matter intake of concentrate and UTWS the total feed costs per lamb on the alternative diets were 5–13% higher than in C (23.4–25.0 USD in the alternative diet groups vs. 22.2 USD in the C group). The economic returns per kilogram of weight gained did not differ, and the feed costs per kilogram weight gain were similar in the three groups (0.90, 0.98 and 0.89 USD in C, FBM and MM, respectively). No differences among groups were observed with regard to carcass traits and quality (P > 0.05). Although no cost-savings were obtained per kilogram of weight gained, the use of locally available feed resources such as molasses has the potential to reduce and stabilize fluctuating feeding grain costs during periods of high grain prices.