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Effects of in‐utero heat stress on post‐natal thermoregulation
Author(s) -
Johnson Jay Steven,
Ross Jason,
Selsby Joshua,
Boddicker Rebecca,
Lucy Matthew,
Safranski Tim,
Rhoads Robert,
Baumgard Lance
Publication year - 2013
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.27.1_supplement.1134.5
Subject(s) - in utero , thermoregulation , hyperthermia , heat stress , zoology , endocrinology , medicine , gestational age , gestation , chemistry , pregnancy , biology , fetus , genetics
Heat stress related issues will become more of a burden as climate models predict that the frequency, intensity and duration of heat waves will increase. Study objectives were to determine the extent in which in‐utero hyperthermia affects post‐natal phenotypic responses to a heat load. We hypothesized that pigs exposed to inutero HS would be more thermo‐tolerant during post‐natal development. Pregnant sows were exposed to thermoneutral (TN; constant 19 – 22°C) or HS (cyclic 28 – 38°C) conditions. Barrows from gestational TN (GTN; 73.0 ± 1.5 kg BW; n = 12), and gestational HS (GHS; 69.7 ± 1.1 kg BW; n = 12) were maintained in TN conditions (21.5°C; n = 6 GTN, n = 6 GHS) or constant HS conditions (34°C; n = 6 GTN, n = 6 GHS). Pigs in HS conditions had increased rectal temperature (Tre) and respiration rate (RR; 0.3°C and 40 bpm; P < 0.01, respectfully), compared to TN pigs. During post‐natal HS, no gestational differences in RR existed (P >; 0.10); however, GHS pigs had increased (0.2°C; P < 0.01) Tre compared to GTN pigs. Post‐natal HS decreased feed intake (26%; P < 0.01), and average daily gain tended (P < 0.07) to decrease (25%), but neither post‐natal variable was influenced by gestational treatments. These data indicate that in‐utero HS alters post‐natal thermoregulation, and appears to allow for greater tolerance (from a productivity standpoint) of increased body temperatures. Supported by USDA/NIFA Grant no. 2011–67003‐30007.