Intake, growth performance, carcass traits, and meat quality of feedlot lambs fed novel anthocyanin-rich corn cobs

Authors: QUADROS, DANILO - Texas A&M Agrilife; KERTH, CHRIS - Texas A&M University; MILLER, RHONDA - Texas A&M University; TOLLESON, DOUGLAS - Texas A&M Agrilife; REDDEN, REID - Texas A&M Agrilife; XU, WENWEI - Texas A&M Agrilife

Submitted to: Translational Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/2/2023
Publication Date: 1/3/2023
Citation: Quadros, D.G., Kerth, C.R., Miller, R., Tolleson, D.R., Redden, R.R., Xu, W. 2023. Intake, growth performance, carcass traits, and meat quality of feedlot lambs fed novel anthocyanin-rich corn cobs. Translational Animal Science. 7(1). Article txac171. https://doi.org/10.1093/tas/txac171.
DOI: https://doi.org/10.1093/tas/txac171

Interpretive Summary: Feed rations for meat animals can affect growth and meat characteristics important to consumers. Rations may be improved and feed costs reduced by introducing foods that are considered byproducts of other farm production, such as corn cobs left over after corn is shelled. Scientists from Texas A&M AgriLife and USDA ARS fed rations that used corn cobs from two sources to see if meat production and quality could be positively impacted. Cobs were used from both regular corn and corn high in anthocyanins (Hi-A), which is an antioxidant associated with better nutrition. Replacing 20% bermudagrass hay with corn cobs in the diets of feedlot lambs did not affect growth performance, meat fatty acid profile, sensory traits, and most carcass characteristics and meat color parameters. Hi-A corn diet improved aroma in cooked boneless loin chops, but sensory traits were not affected. This study showed the Hi-A corn cobs can be safely used for roughage and feed for lambs and for improving meat aroma in cooked boneless loin chops.

Technical Abstract: Feeding anthocyanin- and antioxidant-rich forages to sheep and dairy cows can improve performance and product quality. The objective of this study was to evaluate the impact of feeding anthocyanin-rich (Hi-A) corn cobs on the growth performance and meat quality of lambs. A total of 30 eight-month-old Rambouillet ewe lambs (body weight 30.7 ± 1.2 kg) were fed for 63 days with three diets consisting of 80% concentrate and 20% roughage: Hi-A corn cobs (Hi-A), regular corn cobs (Low-A), and bermudagrass hay (BGH). A completely randomized design trial with 10 lambs per treatment was used. Data were collected on dry matter intake (DMI), body weight (BW), average daily gain (ADG), gain:feed ratio (G:F), carcass traits, meat color, fatty acid (FA) profile, volatile aroma compounds, and sensory panels. After feeding for 63 days, lambs were harvested, and the carcasses were evaluated. Boneless lamb loin chops were fabricated and submitted to FA, aroma, and sensory analysis. The corn cob diets did not affect BW, ADG, or G:F of the lambs compared to BGH diet, but DMI (P < 0.01) was decreased. The dressing percentage was greater (P < 0.05) in lambs fed BGH than in those fed Hi-A, while lambs fed Low-A did not differ from the other two diets. Loin chop instrumental color characteristics were not influenced by diets, except the hue angle, which was greater (P < 0.05) in lambs fed Hi-A than Low-A, while BGH did not differ from lambs fed either cob diet. There was no significant difference in the meat fatty acid profile. Five volatile compounds were affected by diets. The 2-butanone (P = 0.07) and 2,3-butanedione (P = 0.05) were greater in chops from lambs fed BGH relative to lambs fed Hi-A and neither differed (P > 0.05) from lambs fed Low-A diet. The 2-propanone was greater (P = 0.01) in chops from lambs fed BGH than in those fed either the Low-A or Hi-A diets. Both 3-methyl-butanal and methyl benzene were lower (P = 0.01 and P = 0.02, respectively) in chops from lambs fed the Hi-A diet than in those fed either the BGH or Low-A diet. Replacing 20% bermudagrass hay with corn cobs in the diets of feedlot lambs did not affect sheep growth performance, meat fatty acid profile, sensory traits, and most carcass characteristics and meat color parameters. Hi-A corn diet improved aroma in cooked boneless loin chops, but sensory traits were not affected. This study showed the Hi-A corn cobs can be safely used for roughage and feed for lambs and for improving meat aroma in cooked boneless loin chops.