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Heat Stress Lessons Learned and Reducing the Impact. 134 Call Hall Manhattan, KS 66560-1600 785-532-1207 mbrouk@ksu.edu. Dr. Micheal Brouk. OABP Spring Meeting April 13 & 14, 2011 Guelph, Ontario. Background and Experience. Family farm in Missouri - Crop production
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Heat StressLessons Learned and Reducing the Impact 134 Call Hall Manhattan, KS 66560-1600 785-532-1207 mbrouk@ksu.edu Dr. Micheal Brouk OABP Spring Meeting April 13 & 14, 2011 Guelph, Ontario
Background and Experience • Family farm in Missouri - Crop production • 20 years service to feed industry and university • Currently Associate Professor & Extension Dairy Specialist • General nutritionist – KSU Dairy • 28.901 lb/cow rolling herd milk production • 989 lb/fat per cow • 861 lb/protein per cow
Effective Temperature Air Temperature Relative Humidity Air Movement Solar Radiation Buffington, 1983
Heat Stress Reduce Feed Intake Increased Water Intake Increased Respiration Rate Increased Evaporated Water Loss Increased Body Temperature Changes in Metabolic Rate & Hormones Reduced Milk and Reproduction Armstrong & Welchert, 1994
Methods to Reduce Heat Stress Shade Fans Misting Evaporative Zone Air conditioning
Cost Vs. Quality If you can see your shadow, spend more money!!!
Absorption of Solar Radiation 5450 BTU/Hr 84 oF & 21% Humidity THI = 73 (Armstrong and Hillman, 1998)
Shade Design Orientation North-South Allows shade to travel 38 - 50 ft2/cow) 11.5 - 14.5 ft tall Material Cost Vs Shade Quality Useful Life
Where to Shade? Holding Pen Resting Area Feed Area Order is important!!!!!!
Nonevaporative Cooling Evaporative Cooling Outer Body Surface Evaporative Cooling Respiratory Tract
Effect of Sprinkling Frequency and Supplemental Air Movement on Respiration Rate KSU Cow Comfort Consortium 2001 (Brouk, M.J., J.F. Smith and J.P. Harner, III)
Effect of Sprinkling Frequency and Fan Cooling on Udder Skin Temperature KSU Cow Comfort Consortium 2001 (Brouk, M.J., J.F. Smith and J.P. Harner, III)
Message for conventional barns • Cooling is a combination of • Soaking cycles • Temperature Dependent • Increased Frequency of soaking with increased temperature • Increased air movement
Holding Pen Factors Duration 2x (1hr) 3x (.75 hr) 4x (.5 hr) Density Increase in Heat Load Rapid increase in body temperature Cooling effective Decreased Body Temperature 3 oF Increased Milk 1.75 lb/c/d (Wiersma & Armstrong, 1983)
Holding Pen Cooling Fans 1000 ft3/min/cow 30-36 inch =10,000 - 12,000 cfm) 1 per 10 cows or 150 ft2 Spacing Holding Pen Width <24 ft Sidewalls 6-8 ft Holding Pen Width >24 ft Perpendicular to cows 6-8 ft Rows 20 ft (36 in) or 40 ft (48 in) Harner, 1999
Sprinklers Wet the Cow Dry the Cow Prevent Excess Water Design 0.03 gal/ft2 8 x 8 ft grid Water Hose Harner, 1999
2000 Study 36” Fan over stalls & feedline 36” Fan over feedline
Average Milk Production P<.01
Missed Opportunity = Lower Production!!! Last 5 pounds of milk most profitable!!!!!!
Quick TeeJet® Nozzle Body, Check Valve and Cap Turbo FloodJet® Nozzle – TF-VP5 ($1.50) Quick TeeJet Cap and Gasket 25600-1-NYR ($0.60) Nozzle Body and Check Valve QJ8360-NYB ($3.54) Total Cost $5.64
Evaporative Cooling Effective in Arid Conditions Evaporate Water in Air Decrease Temperature Increase Humidity Evaporation Rate Function of Temperature and Humidity
Cellulose Evaporative Pad WATER AIR 41
Potential THI Change Due to Water Evaporation in a Low Relative Humidity Environment KSU Cow Comfort Consortium 2001 (Brouk, M.J., J.F. Smith and J.P. Harner, III)
Potential THI Change Due to Water Evaporation in a High Relative Humidity Environment KSU Cow Comfort Consortium 2001 (Brouk, M.J., J.F. Smith and J.P. Harner, III)
Air inlet with an evaporative pad Two 5 foot evaporative pads – 10 ft wide x 360 ft long Winter inlet – parlor transfer lane 46
Water Usage Per Cow Per Day 24 hr Fence Line Soaker 8’ nozzle spacing, 120 cycles per day (1 on – 11 off) 0.5 gpm – 15 gal/dy/cow 1.0 gpm - 30 gal/dy/cow 16 hr Evaporative Pad 0.33 gal/hr / sqft pad area 4.5 sf/cow – 24 gal/dy/cow (8 row ) 2.75 sf/cow - 15 gal/dy/cow (16 row ) 48
Advantages of Cross Ventilation • Increased cow density • Control of cow environment • Improved feed efficiency • Ease of construction • Improved efficiency of water use
Disadvantage of Cross-ventilation • Energy usage • Maintenance – Pads and Fans • Lighting • Day/night patterns • Issues with door damage • Summertime vs Winter Ventilation • Cow vs people