Effect of gestational and acute postnatal HS on blood gas variables and metabolites.

1<p>iCa, ionized calcium.</p>2<p>PCV, packed cell volume.</p>3<p>GestTrt, gestational treatment.</p>4<p>PostTrt, postnatal treatment.</p>5<p>G x A, interaction between gestational and postnatal treatment groups.</p><p>Different letters indicate GestTrt comparisons P<0.05.</p>#<p>indicates PostTrt comparisons P<0.05.</p><p>Effect of gestational and acute postnatal HS on blood gas variables and metabolites.</p

Acute postnatal heat stress (HS) alters temperature indices and feed intake over the 24 h treatment period.

<p>A) Rectal temperature increased during postnatal HS (<i>P<</i>0.001) and a postnatal treatment by time interaction was also detected (<i>P<</i>0.001). B) Respiration rate presented as breaths per minute (bpm) was elevated as a result of postnatal HS (<i>P<</i>0.001) in addition to the detection of a postnatal treatment by time interaction (<i>P<</i>0.01). C) Skin temperature was increased in pigs subject to postnatal HS compared to thermal neutral <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110859#pone.0110859-Early1" target="_blank">[30]</a> counterparts (<i>P<</i>0.001) in addition to detection of a postnatal treatment by time interaction (<i>P<</i>0.001). A gestational by postnatal treatment interaction was observed in skin temperature (<i>P</i> = 0.05) whereby gestational treatments exposed to HS during the second half of gestation had higher skin temperature (0.5°C) under HS conditions but lower skin temperature under TN conditions (0.3°C) compared to HSTN and TNTN gestational treatments. D) Cumulative feed intake was reduced (<i>P</i><0.01) in HS pigs compared to their TN counterparts. TN pigs gained weight while HS pigs lost weight over the acute HS period. No gestational effect was observed for feed intake or weight gain parameters (<i>P></i>0.1). E) The difference between rectal and skin temperatures is elevated in pigs from TNHS and HSHS vs. TNTN and HSTN treatments at 16 h (<i>P = </i>0.1) and 20 h (<i>P = </i>0.01) of HS. ^#<i>P</i><0.1; *<i>P</i><0.05. Data shown represent the LS-mean ± SEM of n = 6 pigs per postnatal treatment per gestational treatment.</p

Effects of gestational and chronic postnatal heat stress (HS) on body composition indices following chronic (5 weeks) HS exposure (19 weeks of age).

<p>A) An interaction was observed between gestational and postnatal treatments on longissimus dorsi cross-sectional area (LDA) (<i>P = </i>0.045), and a tendency was observed for gestational treatment to have an effect on LDA (<i>P = </i>0.07). B) HSTN pigs have greater subcutaneous fat thickness (SFT) than TNTN and TNHS pigs while HSHS pigs are not different from other gestational treatments (<i>P = </i>0.04). C) Chronic postnatal HS resulted in a reduction in SFT, regardless of gestational treatment (<i>P = </i>0.002). Data show the mean ± SEM of n = 6 pigs per postnatal treatment per gestational treatment. Different letters indicate <i>P<</i>0.05.</p

Effect of gestational treatment on circulating insulin concentrations at the end of the chronic treatment period, regardless of postnatal thermal treatment.

<p>A) Gestational treatment had a tendency to affect circulating insulin concentrations (<i>P = </i>0.0.09). B) Circulating insulin concentrations were elevated in pigs from dams exposed to heat stress (HS) conditions during the first half of gestation compared to those from dams gestated in thermal neutral <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110859#pone.0110859-Early1" target="_blank">[30]</a> conditions during the first half of gestation (<i>P = </i>0.01). Different letters indicate <i>P<</i>0.05.</p

Effects of gestational thermal treatment on postnatal body composition indices at 12 weeks of age and prior to acute postnatal heat stress (HS).

<p>A) Longissimus dorsi cross-sectional area (LDA) is greater in pigs from TNTN dams compared to those from TNHS and HSTN dams, but not different than those from HSHS treated dams (<i>P = </i>0.03). B) No gestational effect is observed in subcutaneous fat thickness (SFT) at 12 weeks of age (<i>P = </i>0.58). Different letters indicate <i>P<</i>0.05.</p