Weather Impact Upon Performance An S 426

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Weather Impact Upon PerformanceAn S 426
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Weather Impact Upon Performance

• Been stated that for an optimum ratio of input to
  output for livestock should have
• 1. Air temperature of 55 65 F
• 2. Relative humidity of 55 65
• 3. Wind velocity of 3-5 mph
• 4. Medium level of sunshine

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Weather Impact Upon Performance

• Illustrated
• Comfort zone the temperature interval during
  which
• no demands are made on the animals temperature -
• regulating mechanisms
• Range
• 1. European beef breeds 30-60 F
• 2. Dairy breeds 40-60 F
• 3. Zeba breeds 50-80 F
• Critical temperature air temperature below or
  above in which the metabolic rate increases to
  maintain constant body temperature

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• A-A Comfort zone minimal thermo-reg. C-D
  Body temp. drops
• B-B Thermoneutrality C-B Sweating
  panting intensity
• A-B Physical Mech. (vaso constr.,
  piloerection) C-D Body temp. increases
• A-B Physical Mech. (vaso dial., sweating
  panting) D-D Survival
• C-C Homeothermy
• C-B Rate of heat prod. increases

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Weather safety can save your livestock

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Weather Impact Upon Performance

• Wind chill chart (OF)
• Wind Velocity (MPH)
• Temp (OF) 10 20 30
• 30 16 3 -2
• 20 2 -9 -18
• 10 -9 -24 -33
• 0 -22 -40 -49
• -10 -31 -52 -63
• -20 -45 -68 -78
• -30 -58 -81 -94

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Weather Impact Upon Performance

• Under normal and moderate conditions feed and
  water intake are closely related inadequate
  water intake will result in cattle eating less.
• In extreme temperature conditions feed and water
  consumption are inversely related feed intake
  increases with extremely cold temperatures and
  decreases with extremely warm temperatures.

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Weather Impact Upon Performance

• Temperature changes have greater effect upon the
  digestibility of roughages than concentrates.
• Cold temperatures increase thyroid activity.
• Thyroid hormone increases rumen and intestinal
  contraction and motility.
• Since feed moves through the GI tract faster,
  digestibility decreases.
• Value of alfalfa hay (V.G.)
• 86F 68F 23F
• ME, Mcal/lb. .89 .87 .85
• TDN, 53.5 53.0 51.7
• DP, 11.5 11.5 11.1

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Weather Impact Upon Performance

• Summary of ISU experiments demonstrating affects
  of
• environment on feedlot performance.
• Effect of season and shelter on performance of
  yearling steers
• Winter Summer
• Shelter No shelter Shelter No shelter
• Daily water cons., gal. 5.07 4.94 7.95
  8.61
• Daily feed cons., lb. 26.64 26.72 25.78
  25.38
• Daily gain, lb. 2.91 2.54 3.00
  2.84
• Lb. feed/lb. gain 9.15 10.52 8.75
  9.1 . P lt .05.
• P lt .01.

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Weather Impact Upon Performance

• Feedlot performance by housing
• and month on test
• Consumptiona
• Started on test Shelter No shelter Confinement
• November 16.14 15.87 14.60
• January 17.26 16.40 15.38
• March 17.45 17.35 15.19
• May 18.06 17.21 16.14
• July 17.11 16.38 15.41
• September 16.84 17.08 15.40
• Average 17.14 16.72 15.35
• aAverage daily feed consumption, lb. of dry
  matter

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Weather Impact Upon Performance

• Feedlot performance by housing
• and month on test
• ADGa
• Started on test Shelter No shelter Confinement
• November 2.38 2.18 2.02
• January 2.71 2.41 2.21
• March 3.01 2.94 2.63
• May 3.21 3.08 2.72
• July 3.05 2.90 2.71
• September 2.56 2.41 2.12
• Average 2.82 2.65 2.40
• aAverage daily gain, lb.

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Weather Impact Upon Performance

• Feedlot performance by housing
• and month on test
• Conversion a
• Started on test Shelter No shelter Confinement
• November 6.77 7.27 7.23
• January 6.36 6.80 6.97
• March 5.80 5.90 5.78
• May 5.63 5.60 5.93
• July 5.62 5.65 5.69
• September 6.57 7.10 7.25
• Average 6.13 6.39 6.48
• a Average feed conversion, lb. of dry matter/lb.
  of gain

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Weather Impact Upon Performance

• Carcass grades by housing
• and month of test
• Yield grade
• Started on test Shelter No shelter Confinement
• November 2.42 2.36 2.45
• January 2.59 2.49 2.34
• March 2.66 2.65 2.55
• May 2.72 2.62 2.63
• July 2.61 2.46 2.57
• September 2.64 2.61 2.43
• Average 2.61 2.53 2.50

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Weather Impact Upon Performance

• Carcass grades by housing
• and month of test
• Quality grade
• Started on test Shelter No shelter Confinement
• November Choice- Choice- Choice-
• January Choice- Choice- Choice-
• March Choice- Choice- Choice-
• May Choice- Choice- Good
• July Choice- Choice- Choice-
• September Choice- Choice- Choice-
• Average Choice- Choice- Choice-

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Weather Impact Upon Performance

• Summary of temperature effects on beef cattle
  feed and
• water intake
• Temperature Feed intake Water intake
• 95 F 10-35 decrease 1 - 2 gal./lb. of DM
• 77-95 F 3-10 decrease .5 - 1.25 gal./lb. of
  DM
• 59 to 77 F similar to NRC .4 - .6 gal./lb.
  of DM
• 41 to 59 F 2 - 5 increase .25 - .5
  gal./lb. of DM
• 23 to 41 F 3 - 8 increase .25 - .5 gal./lb.
  of DM
• 5 to 23 F 5 - 10 increase .25 - .4 gal./lb.
  of DM
• less than 5 F 8 - 25 increase .25 - .4
  gal./lb. of DM

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Estimate of LCT and increase in energy
requirements

• Increased energy Increased haya
• requirement per requirement per
• F below LCT F below LCT
  Wt (lb.) LCT (F) (lb. TDN/day) (lb./day)
• Calf, one week old 110 45 .05
• Heifer, 1.1 lb. ADG 220
• dry, low wind 1 .06 .12
• wet, 10 mph wind 50 .12 .24
• Yrlg. steer, 2.2 lb. ADG 660
• dry, low wind -30 .13 .26
• wet, 10 mph wind 15 .19 .38
• Dry pregnant cow,
• Mid third pregnancy 1100
• dry, low wind -13 .15 .30
• wet, 10 mph wind 19 .20 .40
• aHay contains 50 TDN

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Estimate of LCT and increase in energy
requirements

• Ex. Feed dry pregnant 1100 lb. cows in a winter
  storm with 10 mph at -10 F
• LCT 19 F, therefore conditions 29 F below
  their LCT 19 - (-10) 29
• Additional energy required .20 lb. TDN/F x 29
  5.8 lb. TDN/day
• Since hay is 50 TDN they will need additional
  11.6 lb. of hay/day
• (5.8 lb. TDN/day .50 TDN 11.6 lb. of hay/day)