Relationships between individual animal variation in dry matter intake and animal performance and feed efficiency of finishing beef cattle

Authors: Beck, Matthew; GOUVÊA, VINICIUS - Texas A&M Agrilife; SMITH, J - Texas A&M University; PROCTOR, J - Oklahoma State University; BECK, PAUL - Oklahoma State University; FOOTE, ANDREW - Oklahoma State University

Submitted to: Applied Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/25/2024
Publication Date: 9/16/2024
Citation: Beck, M.R., Gouvêa, V.N., Smith, J.K., Proctor, J.A., Beck, P.A., Foote, A.P. 2024. Relationships between individual animal variation in dry matter intake and animal performance and feed efficiency of finishing beef cattle. Applied Animal Science. 40(5):639-646. https://doi.org/10.15232/aas.2024-02583.
DOI: https://doi.org/10.15232/aas.2024-02583

Interpretive Summary: Day-to-day variation in dry matter intake of individual cattle may be related to negative production outcomes for beef producers. This variation can be assessed using the day-to-day coefficient of variation for dry matter intake (CV). Recently, a novel method of assessing day-to-day variation in dry matter intake has been proposed. This method is termed Euclidean distance (ED). However, the relationship of these methods for assessing intake variation with production variables is poorly understood. Accordingly, scientists from USDA-ARS in Bushland, TX and Oklahoma State University aimed to investigate how intake variation was related to growth performance, feed efficiency, and carcass traits of finishing beef steers. The CV method was associated with poorer average dry matter intake, average daily gain, hot carcass weight, yield grades, and empty body fat. The ED method was associated with poorer average daily gain, feed efficiency, and hot carcass weights. Both methods indicated poorer production outcomes with increased variation in day-to-day dry matter intake. However, the specific trait that these two methods were related to differed.

Technical Abstract: Objective: The objective of this experiment was to evaluate the relationship between two measures of individual animal DMI variation with DMI, ADG, carcass traits, and feed efficiency measures. Materials and Methods: Daily DMI data was collated from 3, previously published experiments where cattle were individually fed using a Calan gate system (American Calan; Northwood, NH) or an Insentec roughage intake control system (Hokofarm Group, Emmeloord, The Netherlands). The day-to-day coefficient of variation in DMI for each animal was calculated (CV). Next, the average Euclidian distance (ED) was calculated. The correlation between CV and ED methods and production traits and efficiency indexes were calculated. Results and Discussion: The CV was (P < 0.01) negatively correlated with DMI (r = -0.65), ADG (r = -0.52), and residual feed intake (RFI; r = -0.41) and positively correlated with residual intake and gain (RIG; r = 0.29). This suggests that cattle with greater CV were more feed efficient. However, CV was negatively correlated (P < 0.01) with HCW (r = -0.46), back fat thickness (r = -0.25), yield grade (r = -0.29), and empty body fat (r = -0.30). The ED was negatively correlated with ADG (r = -0.55), G:F (r = -0.49), residual ADG (RADG; r = -0.57) and hot carcass weight (HCW; r = -0.33). Implications and Applications: The two measures of DMI variation appear to divergently explain DMI variation’s relationship with production traits and feed efficiency. However, cattle with greater day-to-day variation in DMI had poorer production outcomes.