Postnatal consequences of in utero heat stress in pigs

Authors: Johnson, Jay; BAUMGARD, LANCE - Iowa State University

Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/3/2018
Publication Date: 2/1/2019
Citation: Johnson, J.S., Baumgard, L.H. 2019. Postnatal consequences of in utero heat stress in pigs. Journal of Animal Science. 97(2):962-971. https://doi.org/10.1093/jas/sky472.
DOI: https://doi.org/10.1093/jas/sky472

Interpretive Summary: It is well-known that the productivity, health, and pig well-being is compromised during Heat Stress (HS) and the effects during postnatal life in swine have been extensively researched. However, the impact of prenatal HS on swine performance and health during postnatal life are just recently beginning to be appreciated and may contribute significantly to global production losses. Prenatal HS can have a detrimental influence on the subsequent offspring such as a reduced ability to maintain body temperature during heat stress, increased body fat, and reduced productivity. Therefore, preventing gestational HS through improved cooling technologies and management practices is likely the first step to reducing the negative impact on both the sow and the subsequent offspring and improving both the profitability and sustainability of global swine production.

Technical Abstract: Heat stress (HS) negatively impacts pig productivity and well-being as animals attempt to manage the resultant strain response. This is especially true when HS is combined with production stressors (e.g. mixing, weaning, transport, handling, and isolation) that have the potential to increase disease occurrence, morbidity and mortality. While pigs can utilize adaptive physiological mechanisms to compensate these are often unfavorable to efficient livestock production. Specifically, HS decreases weight gain, reduces growth and production efficiency, alters carcass composition, and increases morbidity and mortality. Consequently, decreased animal performance can constrains profitability and affects economic sustainability. In addition to the negative effects of postnatal HS, prenatal HS has long-term consequences that may compromise future piglet well-being and performance. Pigs gestated during HS have an increased postnatal stress response and an increase in maintenance energy requirements. Furthermore, prenatal HS decreases swine birth weight, and increases teratogenicity, core body temperature set-point, and alters postnatal body composition (more adipose tissue and less skeletal muscle). Taken together, the effects of HS during pre- and postnatal pig development negatively influences productivity and well-being, a scenario that threatens the sustainability of global swine production.