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Graduate Student Oral Competition: PHD I
Graduate Student Oral Competition: PHD I
Kouassi Kpodo
Graduate student
Purdue University
West Lafayette, Indiana
Alan Duttlinger
Purdue University
West Lafayette, Indiana
Matthew Aardsma
Purdue University
Lafayette, Indiana
Jacob Maskal
Purdue University
West Lafayette, Indiana
Jay Johnson
Research Animal Scientist
USDA-ARS Livestock Behavior Research Unit
West Lafayette, Indiana
Feed consumption increases body temperature and may delay a return to euthermia and exacerbate intestinal injury following acute hyperthermia recovery in pigs. The study objective was to evaluate the effects of feed removal on body temperature, feeding behavior, and intestinal morphology in pigs exposed to acute hyperthermia and then cooled. Twenty-four gilts (78.53±5.46 kg) were exposed to thermoneutrality (TN; n = 12 pigs; 21.21±0.31°C) for 6 h, or heat stress (HS; 38.51±0.60°C) for 3 h followed by a 3-h recovery period of cooling (HSC; n = 12 pigs; water dousing and TN conditions). Within each temperature treatment, half the pigs were provided feed (F; n = 6 pigs/temperature treatment) and half were not provided feed (NF; n = 6 pigs/temperature treatment). Gastrointestinal (TGI) and vaginal (TV) temperature were recorded every 15 min and pigs were video-recorded to assess feeding behavior. Immediately following the 6 h period pigs were euthanized, and intestinal samples were collected for histology. During the HS period, Tv and TGI were increased overall (P < 0.01; 1.63°C and 2.05°C, respectively) in HSC vs. TN pigs, regardless of feeding treatment. A temperature by feeding treatment by time interaction was detected during the recovery period where TGI was greater (P = 0.03; 0.97°C) for HSC+F compared to HSC+NF pigs from 45–180 min. Feeding behavior was greater overall (P = 0.02; 223.14%) in F vs NF pigs, regardless of temperature treatment. A decrease (P < 0.01) in jejunum and ileum villus height (24.72% and 26.11%, respectively) and villus height to crypt depth ratio (24.40% and 25.52%, respectively) was observed in HSC vs TN pigs, regardless of feeding treatment. Ileum goblet cells were reduced (P = 0.01; 37.87%) in HSC vs TN pigs, regardless of feeding treatment. No other differences were detected for any parameter. In summary, TGI decreased more rapidly following acute hyperthermia when feed was removed.