|MIA, MD - North Dakota State University|
|WINDERS, THOMAS - North Dakota State University|
|AMAT, SAMAT - North Dakota State University|
|DAHLEN, CARL - North Dakota State University|
|SWANSON, KENDALL - North Dakota State University|
Submitted to: Canadian Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/18/2023
Publication Date: 6/12/2023
Citation: Mia, Md GK., Winders, T.M., Serum, E.M., Amat, S., Neville, B.W., Dahlen, C.R., Smith, D.J., Swanson, K.C. 2023. The effects of feeding hempseed cake on pancreatic and jejunal digestive enzymatic activity in finishing heifers. Canadian Journal of Animal Science. https://doi.org/10.1139/cjas-2023-0033.
Interpretive Summary: Hempseed cake is a high protein feed source but is currently not approved for use in beef cattle diets. Increasing protein contents of diets typically increases the secretion of gastrointestinal (pancreatic) enzymes needed for starch digestion in beef cattle. This study found that enzyme activity was not different between heifers fed a diet containing hempseed cake and heifers fed a diet containing dried distillers grains with solubles. Combined with the results from previously published research on growth performance and digestibility our results suggest that hempseed cake is a viable alternative feed ingredient for cattle finishing diets.
Technical Abstract: This study evaluated the effects of feeding hempseed cake on pancreatic and jejunal digestive enzymatic activity in finishing heifers. Angus-crossbred finishing heifers (n = 32; 494 ± 10 kg BW) were fed treatment diets for 111 days containing either 20% (dry matter basis) of dried corn distillers grains plus solubles (DDGS, n = 16) or hempseed cake (n = 16) followed by withdrawal periods of 0, 1, 4, 7, and 8 d. Jejunal and pancreatic tissues were collected at the end of the feeding period. The data were analyzed using a randomized block (withdrawal period) design using the MIXED procedure in SAS. There was greater (P = 0.05) pancreatic tissue mass relative to the body weight in heifers fed hempseed cake than in heifers fed DDGS. There were no treatment differences (P = 0.19) in digestive enzyme activity (U/g of tissue) in pancreatic (a-amylase, trypsin, and lipase) and small intestinal (maltase, glucoamylase, and isomaltase) tissues. In addition, no differences (P = 0.29) were observed for digestive enzyme activity with differing withdrawal periods. Overall, our results suggest that there were no effects of feeding hempseed cake on enzymes responsible for nutrient digestion in the small intestine and that hempseed cake may be useful as an alternative source of protein in cattle fed finishing diets.