Potential of Second Crops of Oil Radish and White Mustard as Fall Grazing Pasture for German Mutton Merino Sheep

Abstract

Second crops of oil radish (Raphanus sativus) and white mustard (Sinapis alba) being in the bloom stage were evaluated for nutritive value for wether lambs (n=5 per crop, BW=35.6 kg) and in situ grazability by ewes (n=15 per crop, BW=50 kg). Animals received no supplemental feed. The two forage crops differed in dry matter (DM) (135 vs. 154 g/kg) as well as in crude protein (148 vs. 206 g), crude fibre (141 vs. 194 g) and N-free extract (550 vs. 482 g) per kg DM. In the feeding trial, total daily DM intake of lambs from oil radish and white mustard differed (1063 vs. 1203 g/head) but was similar in percent bodyweight (3.3-3%). Apparent digestibility of the two forage crops were similar for crude protein (69-70%) and N-free extract (70-71%), but differed (P<0.001) for crude fibre (63 vs. 54%); the values were similar for TDN (61.6-62.9%), DE (11.36-11.61 MJ), ME (9.32-9.52 MJ) and NEm (5.70-5.88 MJ) per kg DM. In the 4-day grazing trial was used rotational grazing, based on results, the oil radish provided a carrying capacity twice as high as white mustard’s notably, 1700 vs. 740 ewe grazing days per ha - equal to 60 ewes grazing one hectare for 28 and 12 days, respectively. Thus, oil radish seemed better to be used as fall grazing pasture for mutton sheep.