Effect of energy source and level, and sex on growth, performance, and carcass characteristics of long-fed lambs

•Lambs offered WSC ad libitum had a greater ADG, off-test, and hot carcass weight.•Lambs offered WSC had greater G:F and lower feed costs per gain compared to AP.•Lambs offered WSC had lighter total GI tract weights compared to lambs offered AP.•Limit-feeding WSC decreased BF and visceral fat in lambs compared to ad libitum WSC. The objective of the present study was to assess energy source, level, and sex of the lamb, on the growth, performance, and carcass characteristics of long-fed lambs (218 days on feed and 294 days of age). Ewe (n = 24) and wether (n = 24) lambs were blocked by sex and stratified by initial weight to pens containing four lambs within a pen, with two pens of each sex assigned to each of the three dietary treatments. The three diets offered were ad libitum access (WSC100) to whole shelled corn (WSC), 85% access of the ad libitum WSC diet (WSC85), and ad libitum access to alfalfa pellets (AP). Lambs offered WSC100 had greater (P