PSIV-B-16 - Effects of Replacing Cottonseed Meal with Carinata Meal on Performance, Intake, and Digestibility in Backgrounding Beef Heifers Consuming a Corn Silage-based Diet

Abstract: The value of carinata, a non-food oilseed crop, has been demonstrated as a high-quality jet fuel alternative and successful cover crop in the southeastern U.S.; however, research is limited regarding carinata as an alternative for commonly used protein sources in livestock. Eighty-four Angus crossbred heifers were used in a generalized randomized block design to evaluate the effects of replacing cottonseed meal with carinata meal on performance, intake, and digestibility in backgrounding corn silage-based diet. Treatments included: corn silage only (C), corn silage + Brassica carinata meal (BCM) at 10% (CS-BCM10) or 20 % (CS-BCM20) inclusion, or corn silage + cottonseed meal at 10% inclusion (CS-CSM). Protein sources were mixed on an as fed basis with corn silage prior to delivery and provided ad libitum, with individual intake measured using the GrowSafe system. Data were analyzed using Proc Glimmix of SAS. An effect of treatment was observed for final body weight (BW; P < 0.01), average daily gain (P < 0.01), and gain to feed ratio (P < 0.01), where CS was least. Dry matter intake (DMI; P = 0.01) was greatest for CS-BCM10. No effect of treatment was observed for residual feed intake (P = 0.94), time ruminating (P = 0.32), or DMI as a percentage of BW (P = 0.10). Intake of nutrients was greatest (P < 0.01) for CS-CSM, except crude protein (CP), which was least (P < 0.01) for CS. Dry and organic matter digestibility was decreased (P < 0.01) in CS but did not differ from CS-BCM10, whereas CP digestibility was greatest (P < 0.01) in CS-BCM20, and neutral and acid detergent fiber digestibility was least (P < 0.01) for CS. Carinata performed similarly to cottonseed meal in backgrounding beef heifers fed a corn silage-based diet, thereby enhancing its value in the southeastern U.S.