Feeding detoxified Ethiopian mustard (Brassica carinata) seed cake to sheep: Effect on intake, digestibility, live weight gain and carcass parameters

In Ethiopia, cultivation and usage of B. carinata is an old practice. The seeds are primarily cultivated for the extraction of oil, the meal that is remained after oil extraction is protein rich (30 – 45%) and may be used either as high protein feed supplement provided that glucosinolate level is reduced or as organic fertilizer. Oil extraction through the use of solvents has proven to be beneficial in improving the feed quality of the oil seed cake produced as by product. This is as a result of removing the anti-nutritional qualities like glucosinolates by the solvents. These technologies are under evaluation at pilot level in Ethiopia. Thus, a study was conducted to investigate the effect of including both untreated and detoxified Ethiopian mustard seed (Brassica carinata) cake as protein source in the concentrate supplement on feed intake, digestibility, and live weight gain using thirty yearling Afar male sheep with an average initial body weight of 17.1 + 0.6 kg. A completely randomized block design with six replicates per treatment was used. The treatments were: 0, 33, 67 and 100% replacement of noug cake by detoxified mustard cake and 67% replacement by undetoxified cake. All animals were fed and managed in individual pens. Feed intake, apparent digestibility, growth rate and carcass parameters did not differ among treatments. The results of the study showed that detoxified Ethiopian mustard seed cake can completely replace noug seed cake when offered in a mixture with wheat bran for growing male sheep fed a basal diet of grass hay.

Keywords:

Afar sheep , Detoxified mustard seed cake , Glucosinolate , Solvent oil extraction