|Ahlberg, Cashley - Kansas State University|
|Allwardt, Kristi - Oklahoma State University|
|Broocks, Ashley - Oklahoma State University|
|Bruno, Kelsey - Oklahoma State University|
|Mcphillips, Levi - Oklahoma State University|
|Taylor, Alexandra - Oklahoma State University|
|Krehbiel, Clint - University Of Nebraska|
|Calvo-lorenzo, Michelle - Elanco Animal Health, Inc|
|Richards, Chris - Oklahoma State University|
|Place, Sara - National Cattlemen'S Beef Association (NCBA)|
|Desilva, Udaya - Oklahoma State University|
|Vanoverbeke, Deborah - Oklahoma State University|
|Mateescu, Raluca - University Of Florida|
|Weaber, Robert - Kansas State University|
|Bormann, Jennifer - Kansas State University|
|Rolf, Megan - Kansas State University|
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/21/2018
Publication Date: 5/22/2018
Citation: Ahlberg, C.M., Allwardt, K., Broocks, A., Bruno, K., McPhillips, L., Taylor, A., Krehbiel, C.R., Calvo-Lorenzo, M., Richards, C.J., Place, S.E., Desilva, U., VanOverbeke, D.L., Mateescu, R.G., Kuehn, L.A., Weaber, R.L., Bormann, J.M., Rolf, M.M. 2018. Test duration for water intake, ADG, and DMI in beef cattle. Journal of Animal Science. 96(8):3043-3054. https://doi.org/10.1093/jas/sky209.
DOI: https://doi.org/10.1093/jas/sky209 Interpretive Summary: Suggested test periods for growth and feed intake in United States beef cattle systems have been established using results of several research trials. The Beef Improvement Federation has subsequently established guidelines for their use in genetic evaluation systems. However, there have been no guidelines for water intake recording. This study evaluated different test lengths for water intake while simultaneously verifying test periods for feed intake and growth. Water intake was evaluated over a series of trials in winter and summer months in order to establish a robust recommendation. Results suggest that test durations of 35d are sufficient for water intake; thus water intake can be recorded during longer intake and gain test periods.
Technical Abstract: Water is an essential nutrient, but the effect it has on performance generally receives little attention. There are few systems and guidelines for collection of water intake (WI) phenotypes in beef cattle, which makes large-scale research on WI a challenge. The Beef Improvement Federation has established guidelines for feed intake (FI) and ADG tests, but no guidelines exist for WI. The goal of this study was to determine the test duration necessary for collection of accurate WI phenotypes. To facilitate this goal, individual daily WI and FI records were collected on 578 crossbred steers for a total of 70 d using an Insentec system at the Oklahoma State University Willard Sparks Beef Research Unit. Steers were fed in five groups and were individually weighed every 14 d. Within each group, steers were blocked by BW (low and high) and randomly assigned to one of four pens containing approximately 30 steers per pen. Each pen provided 103.0 m2 of shade and included an Insentec system containing six feed bunks and one water bunk. Steers were fed a constant diet across groups and DMI was calculated using the average of weekly percent DM within group. Average FI and WI for each animal were computed for increasingly large test durations (7, 14, 21, 28, 35, 42, 49, 56, 63, and 70 d), and ADG was calculated using a regression formed from BW taken every 14 d (0, 14, 28, 42, 56, and 70 d). Intervals for all traits were computed starting from both the beginning (day 0) and the end of the testing period (day 70). Pearson and Spearman correlations were computed for phenotypes from each shortened test period and for the full 70-d test. Minimum test duration was determined when the Pearson correlations were greater than 0.95 for each trait. Our results indicated that minimum test duration for WI, DMI, and ADG were 35, 42, and 70 d, respectively. No comparable studies exist for WI; however, our results for FI and ADG are consistent with those in the literature. Although further testing in other populations of cattle and areas of the country should take place, our results suggest that WI phenotypes can be collected concurrently with DMI, without extending test duration, even if following procedures for decoupled intake and gain tests.