Seeds of Crotalaria spp. contain pyrrolizidine alkaloids that are toxic to a range of animal species. Sunn hemp (Crotalaria juncea L.), a relative of the noxious weed showy crotalaria (C. spectabilis Roth.) known to be toxic to chicken, has only a small amount of those toxins. Two trials examined live performance responses of mixed-sex broilers raised to 21 days of age to determine whether sunn hemp seeds of a breeding population containing 2.5% of the pyrrolizidine alkaloids found in showy crotalaria were detrimental to young broilers. The birds were housed in Petersime battery brooders with eight replicates per treatment (a total of 240 birds). A mash starter feed was fed to 21 days with or without whole Sunnhemp seed. Treatments in included a control, a contamination level (0.5% sunn hemp seed) and an ingredient inclusion level (5% sunnhemp seed). Body weights, feed consumption and feed conversion were be measured by pen at 21 days. Mortality was monitored and posted to determine cause.

Broilers did not consume sunn hemp seeds at the same rate as the rest of the diet. For this reason, sunn hemp consumption was not accomplished at the exact levels stated. Body weights were reduced in birds offered 5% sunn hemp (801.3 vs 849.9 g), but not in birds offered 0.5% (858.0 vs 849.9 g) as compared to the control. Period gains showed a similar pattern. Feed consumption was reduced in birds fed 5% sunn hemp (1.072 vs 1.123 kg/bird), while feed conversion ratio was poorer (1.374 vs 1.322). No significant mortality differences were measured between treatments and no unusual pathologies were noted in the birds during posting.