Effect of Finishing System and Animal Age on Carcass Traits and Nutritional Profile of Bison Bulls
Thesis - Open Access
Master of Science (MS)
Department / School
Bison, Carcass, Fatty acid profile, Grain, Grass, Nutritional composition
The objectives of this thesis project were to 1) evaluate the influence of grain- and grass-finishing systems on carcass characteristics, proximate composition, nutritional profile, and fatty acid composition of bison bull meat, and 2) evaluate the influence of animal age on carcass characteristics of bison bulls. For objective 1, bison bulls were allowed to graze native range in north-central Nebraska until approximately 26 mo of age, when they were randomly assigned to either grain-finishing (n = 98; in an open lot with ad libitum access to prairie hay, alfalfa hay and corn for 95 d prior to slaughter) or grass-finishing (n = 98, on pasture until slaughter). Bulls were harvested at approximately 29 mo of age over a two-day period. Carcass measurements were recorded and strip loins were collected from a subsample of carcasses for compositional analyses. Finishing system influenced the characteristics of bison bull carcasses as well as the nutrient profile of bison meat. Grain-finished bulls had heavier hot carcass weights, larger ribeye areas, increased backfat thickness, while grass-finished steaks had decreased fat content, and cholesterol. Grass-finished steaks also had an increased proportion of poly unsaturated fatty acids compared to grain-finished steaks, which could have potentially meaningful implications to consumer health. For objective 2, bison bulls from a common herd were allowed to graze native range in north-central Nebraska and harvested at two chronological endpoints: Young bulls (n=98) were slaughtered at 29 mo of age; and Mature bulls slaughtered at 36 mo of age following use in the breeding herd. Mature bulls were slaughtered over a one-day period in June 2020, and young bulls were harvested over a two-day period in November of 2020 and carcass measurements were recorded at harvest. Age at slaughter influenced carcass characteristics of bison bulls. Mature bulls had heavier hot carcass weights, larger ribeye areas, and greater marbling, while young bulls had increased backfat. Mature bulls were more likely to have ribeye lean color classified as pale red or red and fat classified as yellow or moderately yellow, while Young bulls were more likely to have ribeye lean color classified as slightly bright red.
Library of Congress Subject Headings
American bison -- Carcasses -- Quality.
American bison -- Feeding and feeds.
American bison -- Age.
Number of Pages
South Dakota State University
Newton, Clay, "Effect of Finishing System and Animal Age on Carcass Traits and Nutritional Profile of Bison Bulls" (2022). Electronic Theses and Dissertations. 468.