K. D. Vogel,* 1 J. R. Claus, T.Grandin,* G. R. Oetzel,# and D. M. Schaefer. Kurt Vogel Colorado State University

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1 K. D. Vogel,* 1 J. R. Claus, T.Grandin,* G. R. Oetzel,# and D. M. Schaefer Kurt Vogel Colorado State University kurt.vogel@colostate.edu 1

2 Marketing options Terminal market Total time: 4-24 hrs May have limited access to water Transaction on live animal weight Good for producer, risky for packer Direct- Grade and Yield Total time: 1 18 hours Must have water in pen at plant Transaction on carcass merit Producer gets true value of animal 2

3 What are the regulations? Slaughter Establishments: 9 C.F.R (e) Animals shall have access to water in all holding pens and, if held longer than 24 hours, access to feed. WI Livestock Markets: ATCP (8c) Provide adequate food, water, shelter, bedding and pen space for all animals held more than 12 hours. ADEQUATE DOESN T MEAN IN ALL HOLDING PENS! 3

4 Study Overview March 17 April 14 Temperature Mean: 34.6 ± 9.8 F 91 cows Live weight: 1350 ± 196 lbs BCS: 2.9 ± 0.5 ( 5 point scale) Minimum BCS: 1.75 Maximum BCS: 4.00 Locomotion score: = Arched back, able to bear weight on all feet 4

5 Study Overview Two part study: Experiment 1 Blood components Stress hormone response Body weight loss Experiment 2 Dressing percentage Fresh meat color Fresh meat composition 5

6 Objectives Establish baseline blood component levels Investigate stress response to water withdrawal Evaluate water withdrawal effects on meat ph, color, and dressing percentage Determine acceptable water withdrawal periods for Holstein slaughter cows 6

7 Materials and Methods: Experiment 1 TWO treatments Control (+ water) 36 hour (- water) Access to hay and water before project start for 24 hrs Health screen (CBC) Evenly dispersed sick cows 7

8 Materials and Methods: Experiment 1 Blood draws: 0, 9, 18, 27, 36 hours 8

9 Materials and Methods: Experiment 1 Samples sent to Marshfield Clinic Labs Held at 2 C until pickup Analyzed for: Acid-base component Serum Chemistry Serum Electrolytes Serum Enzymes Cortisol (RIA) and Packed Cell Volume at University of WI 9

10 Materials and Methods: Experiment 2 THREE treatments Same cows, 18 hour withdrawal added Shipped after 36 hours Treatments mixed before loading Slaughtered within 3 hours of departure Trucked for 90 mins 10

11 Materials and Methods: Experiment 2 All cows slaughtered within 10 minutes All carcasses placed on one rail in cooler 3 lost Excessive trim (2) Rail changer malfunction (1) No condemnations 11

12 Materials and Methods: Experiment 2 In-plant analyses Hot carcass weight Chilled carcass weight From plant records Postmortem ph decline Measured with ph probe 1,2,4,6,8,12,24 hours 12

13 Materials and methods Experiment 2 Out-of-plant analyses rib longissimus Peeled Vacuum packaged Variables: Drip loss Proximate analysis CIE L*a*b* color space Myoglobin approximation 13

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15 Blood Packed Cell Volume 50 Packed Cell Volume (%) Normal Range Hours Control 36 h withdrawal No significant difference observed between treatments. 15

16 Serum Cortisol Indicator of stress Not different (p>0.05) between water treatments. High variability Max: 50 ng/ul Min: 9 ng/ul Possible reasons: Feed withdrawal Mixing unfamiliar cattle Temperament variation Control Cortisol (ng/ul) 36 withdrawal 16

17 Serum Glucose Energy supply for body Glucocorticoids can trigger increase Increases with stress Greater (p<0.05) in 36h withdrawal group b 79.09a Normal Range Glucose (mg/dl) Control 36 withdrawal a,b: denotes difference (p<0.05) 17

18 Percent Muscle Protein 23.0% 22.5% 22.22% a Protein (%) 22.0% 21.5% 21.0% 20.5% 21.16% b 21.11% b 20.0% 19.5% 0 h 18 h 36 h Water withdrawal (hours) a,b: denotes difference (p<0.05) 18

19 Percent Muscle Moisture % Moisture 76.0% 75.5% 75.0% 74.5% 74.0% 73.5% 73.0% 72.5% 72.0% 71.5% 75.02% a 75.05% a 73.57% b 0h 18h 36h Water withdrawal (hours) a,b: denotes difference (p<0.05) 19

20 Muscle Moisture : Protein Ratio a 3.57 a Moisture : Protein b 0h 18h 36h Water withdrawal (hours) a,b: denotes difference (p<0.05) 20

21 Weight Loss Weight loss (%) 7% 6% 5% 4% 3% 2% 1% 0% 3.0% ax 3.8% ax 1.8% by 2.7% bx 3.3% y 0-18 h h 0-36 h Sampling interval 5.2% x 0h withdrawal 36h withdrawal a,b: denotes difference (p<0.05) between sample intervals x,y: denotes difference (p<0.05) between treatments 21

22 Dressing Percentage 70% Dressing Percentage 60% 50% 40% 30% 49.5% 49.2% 50.6% 20% 0h 18h 36h Withdrawal (hours) No significant difference observed between treatments. 22

23 Serum Creatinine mg/dl Normal Range a b Indicator of muscle mass Greater = Heavier Lesser = Lighter Causes of low serum creatinine: 0.4 Extreme starvation Serum Creatinine Muscle wasting Long-term negative energy balance Control 36 h Withdrawal a,b: denotes difference (p<0.05) 23

24 Postmortem ph Decline ph Hours postmortem Typical Values Cows in Study Typical values from Aberle (2001). 24

25 Why was the ph high? Glycogen depletion Energy source after other stores are utilized Takes time! 7 days of starvation in Hereford heifers Took 8 days to replenish McVeigh and Tarrant (1982) Long term negative energy balance Low creatinine, light muscle 25

26 Fresh Meat Color a a b 8.03 a 7.80 ab 7.23 b L* (lightness) a* (redness) b* (yellowness) 0h withdrawal 18h withdrawal 36h withdrawal a,b: denotes difference (p<0.05) 26

27 Conclusions Under the conditions of this study: Water and feed withdrawal up to 36 hours does not elicit a significant cortisol response, but does initiate a glucose increase in Holstein slaughter cows. Holstein slaughter cows lose significantly more body weight between 18 and 36 hours of water withdrawal than if they are allowed access to water, but no difference in weight loss occurs between 0h and 18h. 27

28 Conclusions Under the conditions in this study: Water withdrawal up to 36 hours does not impact the dressing percentage of Holstein slaughter cows. More weight on the rail with water access. Water withdrawal beyond 18 hours in Holstein slaughter cows causes significant reductions in meat redness and moisture. Recommended maximum water and feed withdrawal period is 18 hours to maintain animal body weight and carcass qualities. 28

29 Closing thought Are we reaching the physiological limit of the Holstein dairy cow? BCS scores for these cows were normal. Serum creatinine was near the lower critical limit. Postmortem ph remained high, indicating glycogen depletion. The cows were not exposed to abnormal stress (examples: extreme weather, extended starvation, fighting) 29

30 Acknowledgements: UW Department of Animal Sciences Cargill Regional Beef, Milwaukee, WI Wisconsin Beef Council Dr. Temple Grandin Laura Vogel 30

31 Thank you! Contact Information: Kurt Vogel Department of Animal Science Colorado State University 1171 Campus Delivery Fort Collins, CO

32 References Aberle, E.D., J.C. Forrest, D.E. Gerrard, E.W. Mills Principles of Meat Science. 4 th ed. Kendall/Hunt Publishing Co., Dubuque, Iowa. McVeigh, J.M. and Tarrant, P.V Glycogen content and repletion rates in beef muscle, effect of feeding and fasting. J. Nutr. 112: Smith, B.P Large Animal Internal Medicine. 3 rd ed. Mosby Inc., St. Louis, Missouri. Author Affiliations: *Department of Animal Science, Colorado State University, Fort Collins, Department of Animal Science, University of Wisconsin, Madison, #Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison,