This document summarizes a research study on beef cattle selection and management for drought adaptation. The study involves monitoring the feed and water intake of 840 beef cattle over 70 days to establish baseline consumption. It then restricts water intake over 35 days to simulate drought while continuing to monitor intake, weight gain, behavior, and health. The goal is to identify cattle that are more efficient with limited water and develop selection and management tools for drought adaptation. Results will help beef producers maintain the long-term sustainability and viability of their operations in the face of climate change challenges.
1. Beef Cattle Selection and
Management for Adaptation to
Drought
Megan Rolf
State Beef Extension Specialist
Oklahoma State University
2. Available precipitation (difference between monthly precipitation and potential
evapotranspiration [PET], sum of months with nonzero values) for the
conterminous United States. (Source: USGS Circular 1323; Ne.water.usgs.com)
4. Beef Cattle Water Intake
Consume 760 Billion L per year (Beckett and Oltjen,
1993)
Influenced by physiological and environmental
parameters
Size/weight (i.e. Brody et al. 1954; Ittner et al.
1951,1954)
DMI (Ritzman and Bendict 1924; Leitch and Thompson,
1944)
Ambient temperature and solar radiation (Mader and
Davis 2004; Amundson et al. 2006; Mader et al. 2006)
Sexson et al. 2012 estimated individual WI from
environmental data utilizing 8,000 pen records
R2=0.32
Significant individual animal variation
5. Water
Consumptive water use in the beef industry
Not as important on a LCA scale
Irrigation of pre-harvest water and feed ~95%
Underscores importance of feed efficiency
Critical for an individual farmer
6. Decreased water availability
Amplified by increased evaporation if hot
Decreased water quality from increase in
adulterants
May affect taste and odor, palatability (Lardner
et al. 2005)
Decreased performance likely due to reduced
water and feed intakes (Lardner et al. 2005)
Increased water temperature
Typically increase water demand
Particularly apparent in taurine cattle (Ittner et
al. 1951)
Need to consume more water, when we have
less available and they are less likely to want
to drink it
Water restriction
Increases the spread of maximum and minimum
body temperatures (interferes with body
temperature regulation; Finch 1985)
What to Expect During Drought
J. Anim. Sci Vol. 62 No. 2, p. 531-542
Australian Journal of Agricultural Research. 56: 97–104
7. Project Overview
5 year integrated USDA project
Climate change and mitigation RFA
Adaptability to abiotic stresses
Water availability and quality, temperature-related
stresses
Includes research and extension components
Goal: Develop beef cattle selection and
management tools that address
conservation of water resources and
adaptation to climate variability (drought)
9. Study Design
70 day baseline feed and water intake test
Individual animal (n=840, n=120 each round)
Water intake
Feed intake
Periodic weights (ADG)
Behavioral data (temperament, posture, social interactions,
shade use, motion index, etc.)
Health status (blood cell counts, treatment data for health
interventions, electrolyte balance, hematocrit, etc.)
Heat stress measures (respiration rates, subset with rumen
boluses)
Cold stress measures (behavioral data)
Rumen and fecal samples
Pedometers on a subset of animals in each pen
10. Study Design
70 day adaptation test
Every animal serves as its own control
35 day step-down phase
Water intake restricted by 10% each week until reach 50%
of baseline
35 day extended water restriction period
Maintained at 50% of normal intake for 5 weeks
Feed intake
Periodic weights (ADG)
Behavioral data (temperament, posture, social interactions, shade
use, motion index, etc.)
Health status (blood cell counts, treatment data for health
interventions, electrolyte balance, hematocrit, etc.)
Heat stress measures (respiration rates, subset with rumen
boluses)
Cold stress measures (behavioral data)
Rumen and fecal samples
Pedometers on a subset of animals
11. Study Design
Feed samples (high roughage)
Analyzed for dry matter weekly
Stored for future nutrient analysis
Water Samples (TCFA)
Water quality monitored once/month throughout the
study
Tested in on-campus water lab
Calves maintained in the feedlot through finishing
phase
Impacts on carcass performance
140 control steers (20 in each group)
Collection of tissues at harvest (where possible)
13. Summary Statistics (Cont.)
Number of
Animals
Mean Restriction
Level*
Feed Intake
Reduction
Average Daily
Gain Reduction
Low Water Intake
Group
39 53%ac 22%c 30%d
Medium Water
Intake Group
39 55%ab 19%c 22%de
High Water Intake
Group
39 52%ac 17%c 19%e
14. Results
y = 1.5076x + 0.0729
R² = 0.0756
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.005 0.01 0.015 0.02 0.025 0.03
WaterIntake(as%ofmid-testbodyweight)
Feed Intake (as % of mid-test body weight)
Ad-libitum feed intake and water intake
Figure 1: Graph of ad-libitum water and feed intake expressed as a percentage of mid-test body
weight (to correct for bias due to body size) for steers in group 1 (n=117) over a 70 day feed and water
intake test.
15. y = -0.0004x + 0.102
R² = 7E-05
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.0 0.5 1.0 1.5 2.0 2.5
WaterIntake(as%ofmid-testbodyweight)
Mean Average Daily Gain (kg)
Ad-libitum Water Intake and Average Daily Gain
Results
16. More Still to Come!
6 more rounds of calves (Group 2 will move to finishing April 1 2015)
70K genotyping data (GGP-HD)
Water intake and efficiency
Feed efficiency
Adaptability to abiotic stresses
Heritability estimates and GWAS for these traits
WI highly heritable in laboratory animals (~70%)
Other traits with data collected
Metagenomic sequencing
How is the rumen affected by water quality and availability?
>60% of protein requirement generated by microbes (Church 1993)
10 high and 10 low water intakes
10 most and 10 least adaptable
Rumen and fecal samples before and during water restriction
GHG emissions predictions through modeling
Tissue collections and GHG emissions data (head boxes)?
17. Extension Outcomes
Long-term business viability, stewardship of natural resources,
and responsibility to community, family, and animals
Economic
Environment Social
Focus on
Sustainability
18. Extension Outcomes
Evaluation of consumer perceptions on
beef production sustainability and natural
resource usage
Provide consumer education to fill knowledge
gaps and misconceptions
Online educational modules
19. Tools for Producers
Cattle water demand tool
Expansion of the cattle comfort advisor
20. Extension Outcomes
Long-term business viability, stewardship of natural resources,
and responsibility to community, family, and animals
Economic
Environment Social
Focus on
Sustainability
Cattle comfort advisor:
Reduce economic losses due
to not planning for heat stress
Water Demand
Tool:
Manage on-farm
natural resources
Surveys:
Assess consumer
attitudes towards
sustainability and
natural resource usage
Cattle comfort advisor:
Animal well-being
21. Project Team
Oklahoma State University
Megan Rolf
Michelle Calvo-Lorenzo
Sara Place
Chris Richards
Clint Krehbiel
Udaya DeSilva
University of Florida
Raluca Mateescu
Collaborators
DL Step-OSU Center for Veterinary
Health Sciences
Al Sutherland-Oklahoma
Mesonet
This project was supported by Agriculture and Food
Research Initiative Competitive Grant no. 2014-
67004-21624 from the USDA National Institute of
Food and Agriculture.
Project idea came about in 2012 with OK drought and my parents culling the herd not because of lack of feed resources, but for lack of water (and blue-green algae), had progressed in 2014 to the point that some SW OK producers had no water for their houses