Heat stress basics Cows experience heat stress when effective - PDF document

12/23/2013 An Evaluation of CowKühlerZ Evaporative Cooling System for Heat Stress Abatement in High Producing Dairy Cows Katie Ballard and Katie Ballard and Rick Rick Grant Grant William H. William H. Miner Ag Miner Agricu ricultur ltural Re al Research Institute arch Institute Chazy Chazy, NY NY Heat stress basics  Cows experience heat stress when effective ambient temperature exceeds upper limit of TNZ 1

12/23/2013 Heat stress basics  THI of 68 - threshold for milk loss for cows producing > 77 lb/ d of milk (Zimbelman et al., 2009)  Cows producing > 100 lb/ d? Heat stress basics  Cows become more sensitive to thermal stress as milk production increases due to greater metabolic heat output 2

12/23/2013 Heat production by dairy cow (Smith, 2000) Human metabolism: 1 100-watt light bulb  Lactating cow: 16 100-watt bulbs  Cows give off 4,500 BTU/ hour  Similar to 1,500-watt hair dryer at high setting running for  one hour Cow response to heat stress  Reduced activity  Increased body temperature >102.5 o F  Panting >80 breaths/minute  Reduced DMI, 10-15+%  Reduced milk, 10-20+%  As body temperature rises, cow consumes less feed (Rhoads et al., 2009) to produce less metabolic heat 3

12/23/2013 Heat stress and behavioral responses (Tapki and Sahin, 2006)  As air temp increases from 78 to 104 o F  Eating: decreases 46%  Ruminating: decreases 22%  Standing: increases 34%  Drinking: increases 30%  Locomotion: decreases 19%  Higher producing cows (> 70 lb/ d) more sensitive than low producing cows  Especially for lying/ standing Lying and standing related to body temperature (Hillman et al., 2005)  Cows stand when body temperature reaches ~102 o F; they lie down when it drops below this temperature.  Body temperature mediates cow’s standing and lying response to varying conditions of heat stress.  The quickest way to get a cow to lie down is to cool her body temperature. 4

12/23/2013 Lying decreases with higher temperature (Arnold, 1980) 28 Mean temperature ( o C) 26 24 22 20 18 16 45 55 65 75 % cows lying Increased resti Incre resting g time w me with g th greater ter DIM, milk yiel DIM, mil yield Milk yield (lb/d) 110 (Bach et (Bach et al., al., 2010) 2010) 100 90 ~3.7 ~3.7 lb/d lb/d more milk more milk for for 80 eac each extr extra 70 y y = 49.2 = 49.2 + 3.7 + 3.7 x hour hour r 2 = 0.31 = 0.31 60 2 to 3.5 2 t 3.5 lb/ lb/cow 7 10 13 17 Resting time (h) (Grant, 2005) 5

12/23/2013 Heat stress, lying, and lameness (Cook et al., 2007)  As THI increased from 56 to 75:  Lying time decreased from 10.9 to 7.9 h/ d  Standing in alley increased from 2.6 to 4.5 h/ d  Drinking increased from 0.3 to 0.5 h/ d  Lameness score/ claw lesions increased and were associated with greater standing time, sporadic eating, slug feeding  Lameness peaked ~ 2 months after temperatures peaked Economic consequences of heat stress  Economic loss with minimal abatement (DeVries, 2012)  $600/ cow/ yr for Florida and Texas  Annual hours of THI > 70 were 49 and 36% $72/ cow/ year for Wisconsin   Annual hours of THI > 70 were 9%  Large differences by region of US in heat stress severity  Estimated 2:1 return on investment in New York State (St-Pierre, 2001) 6

12/23/2013 CowKühlerZ Evaporative Cooling System  Unique nozzle system delivers precise spray pattern designed to optimize evaporative cooling while minimizing water use.  System allows for effective cooling over stalls as well as feed bunk. Key questions…  Primary: How does CowKühlerZ system compare with minimal cooling (fans only over stalls)?  Primary: How do lying and rumination activity respond to heat abatement and stall cooling?  Secondary: Can we measure a short- term milk response? 7

12/23/2013 Pen 1 Pen 2 “Minimal” heat abatement: Heat abatement treatments: -fans over stalls -fans over stalls -sprinklers & fans over feeding area • 4 fans, centered over stalls • 52-in diameter blades • ~8 ft from floor • Fans spaced ~ 40 - 48 ft apart • Avg. wind speed: 6 mph cu curtains ns D o o r 3’ 48’ 45’ 40’ 53’ D o o r Feed Alley 8

12/23/2013  Located over feeding area, extends entire length of pen  9’10” from pen floor, 3’3” wide • 5 fans over feeding area • 4 fans, centered over stalls • 52” diameter • 52” diameter blades 10’ 3” from floor Same spacing as Pen 1 • • • Spaced 40’ apart • Avg. wind speed – 6 mph • Avg. wind speed – 7 mph 9

12/23/2013  7’ 7’ above above alley alley floor floor  Soaker heads Soaker heads (Edstrom C440S) (Edstrom C440S) spaced 6’ spaced 6’ apart apart  Total 31 Total 31 soaker soaker heads in heads in Pen 2 Pen 2  Low setting - Low setting - 78°F; 78°F; 2 min/15 2 min/15 min min int. int. 7’ hig 7’ high  High setting - High setting - 90°F; 90°F; 3 min/9 3 min/9 min min int. int.  Attac Attached to to existing fans over existing fans over stalls and feedbunk stalls and feedbunk  Low setting - Low setting - 72°F; 72°F; 1 min/3 1 min/3 min min int. int.  High setting - High setting - 90°F; 90°F; 2 min/3 2 min/3 min min int. int. 10

12/23/2013  Quasi asi-experim experimental ntal ◦ Not a t able t le to co control ntrol extraneous traneous influences fluences ◦ Rando Randomizatio ization of n of trea treatments not tments not f feasible asible ◦ Comparin mparing e g experimental perimental treatments (Pe eatments (Pen 2) 2) against ainst control ntrol or b baseli line ne c cool oling ing (Pen 1 1)  Study Period Study Period ◦ Augus August 6 6 – September eptember 23, 23, 201 2013 ◦ Rotatio Rotation t through rough t treatm eatments: 1-w ents: 1-week ek periods riods  25 cows 25 cows selected/pen lected/pen  Balan Balance ced for pari for parity, , DIM, m M, milk yield ilk yield  All cows receiv All cows received ed rbST rbST Pen 1 Pen 1 Pen 2 Pen 2 Item Ite (C (Con ontrol) ol) (Treatments) (Trea s) n 25 25 25 25 Parity Parity 2.2 2.2±0.9 2.5 .5±1.1 Days in mil Days in milk 175± 75±37 158± 58±112 Mil Milk (lb (lb/d) d) 111± 11±11 111± 11±6 11

12/23/2013 A Edstrom So strom Soakers/ ers/Fans a Fans at • Aug Aug. 6-1 6-12; Sep Sep. 3-9 3-9 Feed Feedbunk + Stall + Stall Fans Fans B CowKühlerZ Co wKühlerZ/Fans at Fans at Fe Feedbu edbunk nk • Aug Aug. 13- 13-19; Sep. Sep. 10 10-16 and and Stall Stalls C Fans Fans only only at Feed at Feedbunk unk and and • Aug Aug. 20- 20-26; Sep. Sep. 17 17-23 CowKühlerZ Co wKühlerZ/Fans at Fans at St Stalls alls D Edstrom So strom Soakers/ ers/Fans a Fans at • Aug Aug. 27- 27-Sep. 3 3 Feedbun edbunk and d Co CowKühlerZ wKühlerZ/Fans at Fans at St Stalls alls Temp Te mp/H /Humid umidity ity Water Usage Water Usage Milk Producti Milk Production Lying time Lying time Activi Activity ty Rumin Rumination 12

12/23/2013 100 100 90 90 80 80 70 70 60 60 50 50 40 40 Temp (F) RH % Temp (F) RH % Pen 1 Pen 1 Pen 2 Pen 2 90 Pen - 1 Pen - 2 85 80 THI - THI - 68 75 70 THI THI 65 60 55 50 45 40 13

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12/23/2013 Heat stress and acidosis 6.6 6.4 6.2 Rumen pH 6 5.8 5.6 5.4 5.2 5 Cool Hot HR HG CHR HHR CHG HHG Cool = 64 o F, 50% RH; Hot = 85 o F, 85% RH HR = 65% Roughage HG = 35% Roughage Mishra et al. (1970) 16

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12/23/2013 Edstr Edstrom m Cow Cow Kuhl KuhlerZ Edstr Edstrom m Soa Soakers Stalls On alls Only ly Kuhl Kuhler erZ Cow ow Kuhl KuhlerZ 8/9/2013 8/22/2013 9/1/2013 9/11/2013 Ruminati Rumination Time on Time Pen 1 Pen 1 319.9 330.9 308.6 276.1 SE SE 16.7 20.8 14.8 22.6 Pen 2 Pen 2 341.0 388.5 356.9 374.8 SE SE 31.6 30.5 27.8 27.4 Activity Ti Acti Time me 8/9/2013 8/22/2013 9/1/2013 9/11/2013 Pen 1 Pen 1 426.6 472.7 458.8 420.3 SE SE 16.5 20.8 24.9 22.0 Pen 2 Pen 2 404.2 422.8 401.9 402.9 SE SE 15.8 20.5 19.2 19.4 Standi Sta ding Bouts Bouts 8/9/2013 8/22/2013 9/1/2013 9/11/2013 Pen 1 Pen 1 12.4 12.6 12.0 12.1 SE SE 0.8 0.8 0.8 0.8 Pen 2 Pen 2 11.4 11.4 10.3 13.0 SE SE 1.0 0.9 0.9 1.1 Lying Time Lying Time 8/9/2013 8/22/2013 9/1/2013 9/11/2013 Pen 1 Pen 1 689.6 639.0 628.0 589.7 SE SE 21.3 27.9 25.0 31.4 Pen 2 Pen 2 698.5 626.2 604.9 615.6 SE SE 30.0 35.4 35.2 36.3 Water Usage r Usage (gallo (gallons) ns) 170 50 220 30 800 699 690 700 600 Minutes/d 500 427 404 Min 400 341 320 300 200 Rumination Lying Activity Pen 1 Pen 2 18

12/23/2013 700 639 626 600 Minutes/d 473 500 423 389 400 Min 331 300 200 Rumination Lying Activity Pen 1 Pen 2 700 628 605 600 Minutes/d 500 459 402 400 357 Min 309 300 200 Rumination Lying Activity Pen 1 Pen 2 19