J. D. Clark
University of Kentucky
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Publication
Featured researches published by J. D. Clark.
Journal of Dairy Science | 2015
B.A. Wadsworth; A.E. Stone; J. D. Clark; D.L. Ray; J.M. Bewley
The objective of this study was to describe the differences in freestall cleanliness and stall temperature between a barn with Dual Chamber Cow Waterbeds (DCCW; Advanced Comfort Technology, Reedsburg, WI) and a barn with rubber-filled mattresses at the University of Kentucky Coldstream Dairy Research Farm from January 18, 2012, to May 3, 2013. Stall cleanliness was measured twice weekly (n=134) by the same 2 observers using a 0.91 m×0.91 m wire grid containing 128 equally sized rectangles (10.16 cm×5.08 cm). This grid was centered at the rear portion of the stall; a rectangle that was visibly wet or had any amount of feces present was defined as a dirty rectangle. Weekly stall temperature (n=66) was measured by the same observer during a.m. milkings in the same predetermined stalls. Feces and wet sawdust were removed from the stalls before stall temperatures were acquired. Temperatures were obtained using a handheld thermometer at 30.48 cm above the stall base as determined via dual laser measurements. Stall temperature was measured on the front, middle, and back of the stall first with clean sawdust and then with the sawdust removed from the stall and wiped clean with a towel. Daily temperature-humidity index (THI) was calculated using Kentucky climate data calculated through the University of Kentucky College of Agriculture via a data logger, located 5.63 km from the Coldstream Dairy Farm. Stall cleanliness was not different between the DCCW barn (26.09±0.89 rectangles) and the rubber-filled mattress barn (23.70±0.89 rectangles). Mean THI throughout the study was 64.39±0.82. Stall temperature was different among THI categories. Temperature-humidity index categories 1 (coldest), 2, 3, and 4 (warmest) had THI ranges of 22.94 to 50.77, 50.77 to 64.88, 64.88 to 78.75, and 78.75 to 101.59, respectively. Stall temperatures (°C; least squares means±SE) were 2.26±0.30, 8.86±0.30, 15.52±0.30, and 20.95±0.30 for THI categories 1 to 4, respectively. Stalls with rubber-filled mattresses had a lower temperature (°C) than DCCW with least squares means±SE of 10.52±0.21°C and 13.29±0.21°C, respectively. The DCCW were probably significantly warmer because water holds heat well. The DCCW may have more of a heat-insulating effect compared with rubber-filled mattresses.
Journal of Animal Science | 2016
B.A. Wadsworth; A.E. Stone; J. D. Clark; J.M. Bewley
The Professional Animal Scientist | 2017
Barbara W. Jones; A.E. Stone; Connie L. Wood; Kristen McQuerry; J. D. Clark; Denise L. Ray; J.M. Bewley
Journal of Animal Science | 2016
H. B. Reichenbach; B.A. Wadsworth; J. D. Clark; J.M. Bewley
Journal of Animal Science | 2016
M. L. Jones; J. D. Clark; N. A. Michael; J.M. Bewley
Journal of Animal Science | 2016
B.A. Wadsworth; J. D. Clark; J.M. Bewley
Journal of Animal Science | 2016
A. J. DiGennaro; A. R. Lee; B.A. Wadsworth; J. D. Clark; J.M. Bewley
Journal of Animal Science | 2016
A. R. Lee; S. M. Smith; D.L. Ray; J. D. Clark; J.M. Bewley
The Professional Animal Scientist | 2015
J.L. Lowe; A.E. Stone; K.A. Akers; J. D. Clark; J.M. Bewley
Archive | 2013
Barbara A Wadsworth; Amanda E Sterrett; Connie L. Wood; Kristen McQuerry; J. D. Clark; Denise L. Ray; J.M. Bewley