Assessing Performance and Safety of Feeding a Standardized Macleaya cordata Extract to Calves

SIMPLE SUMMARY: A preparation of the Macleaya cordata extract (Sangrovit(®)) provides a unifying taste to feed for cattle. However, information is needed to see if the effect occurs when fed in milk replacer or starter feed to calves and residues of the extract end up in the tissues. Male and female calves (~5 d of age; 5/sex/group) were provided Sangrovit(®) in milk replacer and starter feed at control (0.0 Sangrovit(®)), 2.0 and 4.0 g (D1), 5.0 and 10.0 g (D2) and 10.0 and 20.0 g (D3) Sangrovit(®)/day, respectively, for 90 days. Body weight, feed intake and blood-derived endpoints were evaluated along with tissue residue levels of Sangrovit(®). Compared to the control group, Sangrovit(®) tended to increase milk-replacer intake (4%). Average daily gain did not change, and some blood chemistry and hematology parameters changed with Sangrovit(®) intake, but were within the ranges of healthy calves. Residues of Sangrovit(®) were located in the edible tissues of the calves. Sangrovit(®) can be added to milk replacer and calf starter feeds with no adverse effects on feed intake, health, or growth of the calves. ABSTRACT: This study examined the effects of Sangrovit(®), a Macleaya cordata plant extract (MCE) preparation on feed intake, growth, blood chemistry, and tissue-residue levels of calves. Twenty male and 20 female calves (~5 d of age) were assigned to one of four daily Sangrovit(®) doses: 0.0 and 0.0 (CTL), 2.0 and 4.0 (D1), 5.0 and 10.0 (D2), and 10.0 and 20.0 (D3) g/calf in pre-weaning (5 to 49 d of age) and post-weaning (50 to 95 d of age) periods, respectively. Sangrovit(®) doses were fed in milk replacer pre-weaning and top-dressed on calf starter post-weaning. Milk replacer and calf starter intake was recorded daily. Body weight, hematology, and serum chemistry were measured at 5, 49, and 95 d of age. Calves were slaughtered at 95 d of age for MCE tissue residue analysis. Compared to CTL, D1 increased milk-replacer intake (4.90 to 5.09 L/day), but decreased calf starter intake pre- (0.65 to 0.53 kg/d) and post-weaning (3.42 to 3.20 kg/d). No Sangrovit(®) dose affected average daily gain. The hematology and blood chemistry of all treatment groups fell within the ranges of healthy calves. Results showed no adverse effects of MCE on health and growth performance of calves when fed up to 10.0 g/calf/day pre-weaning and up to 20.0 g/calf/day post-weaning.