Monovalent Copper Oxide in Broiler Nutrition: Effects on Performance, Intestinal Lesions, and Oocyst Shedding During Mild Eimeria Challenge

Coccidiosis is a major economic threat in poultry, and with anticoccidials being phased out, cost-effective alternatives like copper (Cu) supplementation are of interest. This study investigated whether in-feed monovalent Cu (100 ppm) could mitigate the effects of a mild <i>Eimeria</i> challenge in broilers. A total of 216 broiler chicks were randomly assigned to three treatments (six replicates, 12 birds/replicate): unchallenged control (NC), challenged control (PC), and challenged + Cu-supplemented. Birds were fed starter (days 1-10), grower (days 10-21), and finisher (days 21-35) diets. On day 14, all birds except the NC group were orally challenged with 5000 oocysts each of <i>Eimeria acervulina</i> and <i>E. maxima</i>. Feces were collected (days 17-28) for oocyst count, and growth performance, lesion scores (day 21), carcass traits and bone morphology (day 35), gut morphology (days 21 and 35), gizzard weight (days 21 and 35), and cecal bacterial load (days 21 and 35) were evaluated. The mild challenge was confirmed by the observed differences in lesion scores on day 21 (<i>p</i> < 0.05), fecal oocyst counts from days 17-28 (<i>p</i> < 0.05), and overall mortality (<i>p</i> > 0.05) between challenged and unchallenged groups. Copper supplementation tended to improve FCR during the grower phase (1.403 vs. 1.469; <i>p</i> = 0.057) and significantly reduced oocyst excretion on days 23-25 (<i>p</i> < 0.001) compared to the PC treatment. Although performance benefits were limited, Cu reduced oocyst shedding, indicating potential anticoccidial effects. However, further studies are needed to confirm the consistency of this effect across different doses of Cu in poultry production.