Aerial parts of cassava as partial replacement for feed concentrates in the diet of lambs raised in semi-confinement

This study aimed to evaluate the performance and economic viability of including the aerial parts of cassava (PAM) in the feed of semi-confined lambs for partial reduction of food concentrates. Fifty-six sheep, including males and females of the Pantaneira genetic group weighing 18.84 +/- 2.02 kg on an average were used. The experiment was conducted in a factorial randomized complete block design with four treatments, each with seven females and seven males. Each group of 14 animals received one of four treatments: control, 10% of food concentrate in diet replaced with PAM, 20% replaced with PAM, and 30% replaced with PAM. The average total gain in weight (GWT) of the male lambs was 26.89% higher than the gains observed in females. Based on the cost analysis, we observed a linear effect (P < 0.01), i.e., a decrease in the feed cost for male and female groups with increase in PAM content. For the study period, the expenditure for the control male group was the highest at $ 17.60 per animal. Expenditure for the PAM 30 male group was the lowest at $ 12.74 per animal. These figures reflect the actual operating costs (COE), i.e., the power is 75.78% and 74.77%, for male and female groups respectively. The total cost, decreased linearly (P < 0.05) with PAM 30 treatment costing the least at $ 47.90, which was $ 7.02 lower than the control. When assessing the net margin per kilogram among the female groups, we observed a quadratic effect (P < 0.01) with a maximum gain of 23.98% when adding PAM and $ 0.50 kg(-1). Our results show that the raising of lambs in semi-confinement was economically viable, and the addition of the aerial part of processed cassava in the feed presented a higher economic return. Further, the addition of aerial parts of cassava did not affect the performance of the lambs.