PSVI-28 - Performance of hair lambs maintained on stockpiled permanent pasture mixed with Cleome gynandra L. at multiple stocking densities

Stockpiled forage may extend the grazing season for sheep, reducing feeding costs. Additionally, internal parasites are a problem in sheep managed under grazing conditions. Plants high in phenolic compounds have potential to reduce parasite problems. Cleome gynandra is one such plant that has traditionally been used to treat worms in humans. Thirty-six Katahdin × Dorper lambs (38.8 ± 0.7 kg) were used to investigate the effect of stockpiled forages on lamb performance at different stocking densities: (i) 23 lambs/ha (LOW), (ii) 46 lambs/ha (MED), and (iii) 92 lambs/ha (HIGH). To test C. gynandra for anthelmintic properties, lambs were assigned to (i) permanent pastures (PP), and (ii) PP inter-seeded with C. gynandra (CL). The LOW lambs had the highest ADG (83.8 ± 10.5 g/day), MED lambs were intermediate (48.4 ± 11.6 g/day) and HIGH lambs were lowest (11.0 ± 10.6 g/day; P < 0.001). Lamb BCS did not differ between stocking densities or pasture types (P > 0.10). Fecal egg counts did not differ (P > 0.10) between pasture treatments. In conclusion, stockpiled forages may extend the grazing season for yearling lambs in Southern California. The lack of effect on parasite egg counts may be attributed to grazing C. gynandra at mature stage when nutritional and medicinal values were at their lowest. Future research can clarify the economics of grazing stockpiled forages for sheep at different stages of production, and nutritional effect of C. gynandra on carcass quality.