Replacement of soybean meal with treated castor bean meal in supplements for grazing lambs

Abstract

SUMMARY The objectives of this trial were to evaluate intake and nutrient digestibility, weight gain, and carcass characteristics of grazing lambs supplemented with increasing dietary inclusion of castor bean meal (CBM). Thirty-six Santa Inês-crossed, non-castrated, 120 ± 15 d old lambs (initial BW = 21.8 ± 3.4 kg) were randomly allotted to 1 of 4 dietary treatments. The treatments consisted of 4 levels of soybean meal substitution with lime treated CBM (0, 33, 67, and 100%) on the DM basis. The experimental design was a completely randomized design with 4 treatments and 9 replicates (lambs) for each treatment. Supplementation level was 1.6% BW per animal/d. There was a linear decrease (P<0.01) for total DM intake and a quadratic effect (negative; P = 0.05) for pasture intake as CBM was increased in the supplement. There was a negative quadratic effect of CBM inclusion on NDFap intake, both in g/d (P = 0.01) and as in BW % (P = 0.05). There was a linear effect (negative; P<0.01) on DM and NDFap digestibility coefficients. There were no effects (P≥0.48) of treatments on HCW, dressing percentage, carcass conformation, back fat or carcass length. Despite some negative effects on intake and nutrient digestibility, increasing CBM inclusion in the supplement, up to the substitution of all the soybean meal in the supplement, did not affect weight gain of grazing lambs or carcass characteristics.

Detoxified castor-bean meal replaces soybean meal in the diet of pasture-finished steers

“…The replacement of soybean meal with DCM did not influence the cattle's performance, possibly due to the adequate intake of protein and energy provided by the diets including DCM. Freitas et al (2017) and Araújo et al (2021) also did not observe an effect of including DCM in the supplement on the performance of meat sheep and grazing beef cattle, respectively. In the present study, average daily gain was higher than the 0.50 kg d -1 estimated in the formulation of the diets.…”