Weight gain, grazing behavior and carcass quality of desert grass-fed Rarámuri Criollo vs. crossbred steers

Authors: MCINTOSH, M - New Mexico State University; CIBILS, A - New Mexico State University; Estell, Richard - Rick; NYAMURYEKUNG'E, S - New Mexico State University; Gonzalez, Alfredo; GONG, Q. - New Mexico State University; CAO, H. - New Mexico State University; Spiegal, Sheri; SOTO-NAVARRO, S - New Mexico State University; BLAIR, A - San Diego State University

Submitted to: Livestock Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/1/2021
Publication Date: 7/20/2021
Publication URL: https://handle.nal.usda.gov/10113/7341375
Citation: McIntosh, M.M., Cibils, A.F., Estell, R.E., Nyamuryekung'E, S., Gonzalez, A.L., Gong, Q., Cao, H., Spiegal, S.A., Soto-Navarro, S.A., Blair, A.D. 2021. Weight gain, grazing behavior and carcass quality of desert grass-fed Rarámuri Criollo vs. crossbred steers. Livestock Science. 249:104511. Online #104511. https://doi.org/10.1016/j.livsci.2021.104511.
DOI: https://doi.org/10.1016/j.livsci.2021.104511

Interpretive Summary: Rarámuri Criollo cows have behavioral traits that are desirable for rangelands in arid environments, but calves from this biotype are difficult to market through conventional methods. One strategy to improve marketability is to crossbreed these cows with traditional beef breed bulls. However, it is unclear whether crossbred calves will achieve marketable weights and carcass qualities on rangeland and whether they will retain the desirable grazing behaviors of their mothers. We evaluated these traits for two cohorts of Rarámuri Criollo (JRC), Mexican Criollo (MC), and Criollo × beef-breed crossbred (XC) steers. Final live and carcass weights of XC were greater than JRC and MC, but all three groups were market ready at 30-mo after finishing on grass. Carcass quality and average daily gain did not differ among biotypes. Both JRC and XC steers exhibited grazing patterns similar to those previously observed in JRC cows. These results suggest JRC, MC, and XC steers can achieve desirable slaughter weights in 30 months using a rangeland-based grass-fed protocol, and JRC and XC steers retain desirable grazing behaviors of JRC cows.

Technical Abstract: Rarámuri Criollo cattle producers often crossbreed their cows with improved beef-breed bulls or retain and/or develop their yearlings on rangeland because of limited weaned calf markets, however it is unknown if Rarámuri Criollo steers exhibit marketable weight gains and carcass qualities, or desirable grazing behaviors documented in cows of this biotype. We evaluated two cohorts (cohort: 1 = 31, 2 = 26) of Rarámuri Criollo (JRC), Mexican Criollo (MC) and Criollo × beef-breed crossbred (XC) steers to investigate effects of biotype on growth, carcass traits, and landscape utilization. Steers were weighed approximately once every 2-mo and average daily gains (ADG) calculated. Nine JRC and XC steers per cohort were monitored at 5-min intervals via global positioning systems (GPS) for 1-mo during winter (2015-16) and late-summer (2016-17). Weight and carcass data were analyzed using mixed measures procedures to identify differences between biotype through time. Discriminant analyses were conducted to determine whether grazing behaviors could be discriminated among: 1) JRC and XC steers and JRC cows; 2) steers by season (winter vs. summer); and 3) steers of cohort 1 and 2. Final live and carcass weights of XC were greater than JRC and MC, but all were market ready at 30-mo following a grass-finishing protocol. Carcass quality and ADG were not different among biotypes. Steers were discriminated into different season or cohort groups based on grazing behavior differences but JRC and XC steers exhibited grazing patterns that were similar to those previously observed in JRC cows. Our results suggest that JRC, MC, and XC steers can be developed to slaughter weights in 30-mo using a rangeland-based grass-fed protocol, and that JRC and XC steers exhibit desirable grazing behaviors previously observed in JRC cows.