Characterization of water intake and water efficiency in beef cattle

Authors: AHLBERG, CASHLEY - Kansas State University; ALLWARDT, KRISTI - Oklahoma State University; BROOCKS, ASHLEY - Oklahoma State University; BRUNO, KELSEY - Oklahoma State University; TAYLOR, ALEXANDRA - Oklahoma State University; MCPHILLIPS, LEVI - 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; Kuehn, Larry; 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: 11/8/2019
Publication Date: 11/19/2019
Citation: Ahlberg, C.M., Allwardt, K., Broocks, A., Bruno, K., Taylor, A., McPhillips, L., Krehbiel, C.R., Calvo-Lorenzo, M.S., Richards, C.J., Place, S.E., DeSilva, U., VanOverbeke, D.L., Mateescu, R.G., Kuehn, L.A., Weaber, R., Bormann, J., Rolf, M.M. 2019. Characterization of water intake and water efficiency in beef cattle. Journal of Animal Science. 97(12):4770-4782. https://doi.org/10.1093/jas/skz354.
DOI: https://doi.org/10.1093/jas/skz354

Interpretive Summary: Water is a critical component in agricultural sectors. However, demand for water resources may decrease water availability or increase its cost in production. Thus, decreasing water requirements in livestock could stabilize resources and increase efficiency of production. This study quantified variation in water efficiency measures in beef cattle using daily water and feed intakes collected over several 70-d test periods. Results suggested that efficiency of water use is heritable and could be incorporated into selection programs with minimal detrimental effects on feed efficiency or gain. Thus measurement of water intake for genetic improvement programs could result in improved efficiency and water stewardship in livestock agriculture.

Technical Abstract: In the future, water may not be as readily available due to increases in competition from a growing human population, wildlife, and other agricultural sectors, making selection for water efficiency of beef cattle increasingly important. Substantial selection emphasis has recently been placed on feed efficiency in an effort to reduce production costs, but no emphasis has been placed on making cattle more water efficient due to lack of data. Thus, the objective of this study was to calculate water efficiency metrics for cattle and evaluate their relationship to growth, feed intake, and feed efficiency. Individual daily feed intake (FI) and water intake (WI) records were collected on 578 crossbred steers over a 70-d test period. Animals with low water intake ate less feed, had lower gains, and were more water efficient (as defined by water to gain ratio, W/G, and residual water intake, RWI). However, the amount of water consumed by animals had minimal phenotypic relationship with feed efficiency (RFI, R2 =0.1050 and F/G ratio R2=0.0726). Cattle that had low dry matter intake (DMI) consumed less water, had lower gains, had lower residual feed intake (RFI), and had higher feed to gain ratio (F/G). The level of feed consumed had minimal relationship with water efficiency. Water intake, W/G, RWI and average daily gain (ADG) had moderate heritability estimates of 0.39, 0.39, 0.37 and 0.37, respectively. High heritability estimates were observed for dry matter intake (DMI) and RFI (0.67 and 0.65, respectively). Feed to gain had a low heritability estimate of 0.16. Water intake had a strong positive genetic correlation with W/G (0.99) and RWI (0.88), thus selecting for decreased water intake should also make cattle more water efficient. The genetic correlation between WI and ADG was 0.05; thus, selecting for low WI cattle should have little effect on growth. There is a low to moderate genetic correlation between WI and DMI (0.34). Residual water intake has a positive genetic correlation with W/G ratio (0.89) and F/G ratio (0.42) and is negatively genetically correlated with RFI (-0.57). Water to gain and F/G had a strong positive genetic correlation (0.68). Residual feed intake has a positive genetic correlation with W/G ratio (0.37) and F/G (0.88). Minimal antagonisms seem to be present between WI and ADG. However, care should be taken to ensure that unintended changes do not occur in DMI or other production traits and incorporation of WI into a selection index would likely prove to be the most effective method for selection.