Performance and carcass characteristics of lambs fed diets with increasing levels of Mimosa tenuiflora (Willd.) hay replacing Buffel grass hay.

Abstract

This study evaluated the performance and carcass characteristics of lambs fed diets with increasing levels of Mimosa tenuiflora (Willd.) hay replacing Buffel grass (Cenchrus ciliaris). Twenty-eight Santa Inês male lambs with an average body weight (BW) of 20.3±1.49kg(mean±SD) were allocated in individual stalls and distributed in a completely random design with four treatments (0, 20, 40, and 60g/100g total DM M. tenuiflora hay replacing Buffel grass hay in diet) with seven replications. M. tenuiflora hay at the level of 20% dry matter (DM) total replacing Buffel grass hay increased final weight (P=0.006), total weight gain (P<0.001), average daily weight gain (ADWG; P<0.001), DM intake (P<0.001), and feed efficiency (P<0.001). Intake of crude protein, NDFap, ADFap, ash, ether extract, total and non-fibrous carbohydrates, and total digestible nutrients presented a positive quadratic effect with M. tenuiflora hay replacing Buffel grass hay and 40g/100g total DM level presented greater intake. There were positive quadratic effects by M. tenuiflora hay inclusion at 20g/100g total DM level on slaughtering weight (P=0.005), hot carcass weight (P=0.002), cold carcass weight (P=0.002), empty body weight (P=0.001), hot carcass yield (P=0.002), cold carcass yield (P=0.003), and increase linear on biological yield (P=0.003). There was no influence on cooling weight loss (P=0.284). M. tenuiflora hay may be included in lamb diets at amounts up to 20g/100g total DM substitution of Buffel grass hay because increase in the nutrients intake, growth performance, and carcass characteristics.