Evaluation of Peanut Skins (Testa) as a Feed Ingredient for Growing-Finishing Cattle

Abstract

A grazing study, two feedlot trials and a metabolism study were conducted to determine the value of peanut skins as a dietary ingredient for growing-finishing cattle. Heifers that grazed rye pasture and were fed .91 kg of corn plus .91 kg of peanut skins had greater gains than those fed 1.82 kg of corn as a supplement. Feedlot heifers fed diets that contained 0, 10 or 20% peanut skins consumed 7.84, 7.76 and 6.52 kg of feed/d and gained (P<.05) an average of 1.38, .70 and .14 kg/d, respectively. While the apparent digestibility of ether extract was similar for all three diets, the digestibility of crude protein in the control diet was 31 and 89% higher (P<.05) than in the 10 and 20% peanut skin diets, respectively. For steers confined to metabolism crates, digestibility of crude protein was 61, 44 and 31% (P<.05) for control, 10 and 20% peanut skin diets, respectively. Steers fed the 20% peanut skin diet retained about 60 and 50% less N/d (P<.05) than those fed the control and 10% peanut skin diets, respectively. Daily gain and crude protein digestibility was not different (P>.05) for feedlot steers fed diets that contained 0, 4.8 or 9.1% peanut skins. Ether extract digestibility was greater (P<.05) in diets that contained 4.8 and 9.1% peanut skins than for the control diet. There was no difference (P>.05) in dressing percentage due to diets, but steers on the 4.8% peanut skin diet graded higher and were fatter (P<.05) than those fed the control diet. Therefore, the feeding value of peanut skins appears to be related to the amount of tannin consumed relative to the amount of protein consumed and required.