Plasma Heat Shock Protein 70, Physiological and Behavioral Responses of Gilts to Varying Temperature Humidity Index in a Controlled Chamber

Carla Alilie A. Lontoc1*, Pauline Joy R. Cajano2,
Antonio A. Rayos1, and Renato SA. Vega2

1Animal Production Division, Institute of Animal Science, College of Agriculture
and Food Science, University of the Philippines Los Baños, College, Laguna 4031 Philippines
2Animal Physiology Division, Institute of Animal Science, College of Agriculture
and Food Science, University of the Philippines Los Baños, College, Laguna 4031 Philippines


*Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.; This email address is being protected from spambots. You need JavaScript enabled to view it.


The study aimed to determine physiological, behavioral, and extracellular heat shock protein 70 (HSP70) responses among gilts exposed to increasing temperature humidity index (THI). Individually caged, F1 gilts (N=3) were adjusted for a week given ad libitum commercial diet and water supply in an environmentally controlled chamber, after which the THI  (65, 71, 77, and 83) was elevated every three days for a total of 12 days. Physiological responses [respiration rate (RR), pulse rate (PR), rectal temperature (RT)] and plasma HSP70 were all collected during their first day exposure at 65, 71, 77, and 83 THI. Behavioral responses – meal intake (MI), meal break (MB), standing, lying down, drinking, urination, and defecation – were recorded and counted for frequency and duration at three different periods of the day (08:00–15:00h, 15:01–23:00h, and 23:01–07:59h) using internet protocol cameras. Results showed that RR and plasma HSP70 concentration obtained significant differences at 83 and 71 THI, respectively. Frequency and duration of meal intake and meal break decreased, consistent with the reduction in voluntary feed intake (P<0.05). Among the responses, meal intake duration is the most visible heat stress response that significantly occurred at 77 THI (27 °C), showing meal intake duration reduced by 556 s i.e., 25% of 2212 s (37 min) for the seven-hour period after feed is offered.


Gilts lack sweat glands and are therefore highly sensitive to changes in temperature. Thus, they need to develop a wide range of thermoregulatory behaviors to maintain physiological homeostasis (Pedersen et al. 2003; Olczak 2015). Respiration rate, pulse rate, and rectal temperature have been reported to increase along with the increase in temperature (Huynh et al. 2005; Phuoc et al. 2005) more


BLOEMHOF EH, VAN DER WAAJ EH, MERKS JWM, KNOL EF. 2008. Sow line differences in heat stress tolerance expressed in reproductive performance traits. J Anim Sci 86: 3330–37
COLLIN A, VAN MILGEN J, DUBOIS S, NOBLET J. 2001. Effect of high temperature on feeding behaviour and heat production in group-housed young pigs. British Journal of Nutrition 86: 63–70.
CUSABIO. 2013. ELISA Kit: User Manual (USA) for Pig Heat Shock Protein 70 (HSP-70). CSB–E08317p
DEBRECÉNI O, LEHOTAYOVÁ A, BUCKO O, PETRAK J. 2014. The Behaviour of the Pigs Housed in Hot Climatic Conditions. Journal of Central European Agriculture 15(1): 64–75.
HUYNH T, AARNINK AJA, GERRITS WJJ, HEETKAMP MJH, CANH TT, SPOOLDER HAM, KEMP B, VERSTEGEN MWA. 2005. Thermal behaviour of growing pigs in response to high temperature and humidity. Applied Animal Behaviour Science 91(1–2): 1–16.
LAMMERS PJ, STENDER DR, HONEYMAN MS. 2007. Environmental Needs of the Pig. Niche Pork Production. IPIC NPP110 2007.
MARTIN WR. 2012. Effects of heat stress on thermoregulation, reproduction and performance of different parity sow. [Ph.D. Thesis]. University of Missouri.
[NOAA] National Oceanic and Atmospheric Administration. 1976. Livestock Hot Weather Stress. Operations Manual Letter C-31-76. Kansas City.
OLCZAK K, NOWICKI J, KLOCEK C. 2015. Pig behaviour in relation to weather conditions – a review. Ann. Anim. Sci. 15(3): 601–610.
OKSALA KJ,  EKMEKCI FG, OZSOY E, KIRANKAYA S, KOKKOLA T, EMECEN G., LAPPALAINEN J, KAARNIRANTA K, ATALAY M. 2014. Natural thermal adaptation increases heat shock protein levels and decreases oxidative stress. Redox Biology 3: 25–28.
PEARCE SC, GABLER NK. ROSS, JW, ESCOBAR J, PATIENCE JF, RHOADS RP BAUMGARD LH. 2013. The effects of heat stress and plane of nutrition on metabolism in growing pigs. Journal of Animal Science 91: 2108–18.
PEARCE S. 2014. Evaluation of the chronological impact heat stress has on swine intestinal function and integrity. [Ph.D. Thesis]. Paper 14010. Digital Repository at Iowa State University.
PEDERSEN S, SOUSA P, ANDERSEN L, JENKEN KH. 2003. Thermoregulatory behaviour of growing-finishing pigs in pens with access to outdoor area. Agricultural Engineering International: the CIGR Journal of Scientific Research and Development. Manuscript BC 03 002.
PHUOC LV, NGOAN LD. 2005. Effect of the environmental factors on physiological parameters, feed intake and growth of Mongcai and Landrace pigs in central Vietnam. Workshop-seminar "Making better use of local feed resources." MEKARN–CTU: Cantho. Retrieved on 29 Oct 2015.
QUINIOU N, NOBLET J. 1999. Influence of high ambient temperatures on performance of multiparous lactating sows. J. Anim Sci. 77: 2124–34.
QUINIOU N, DUBOIS S, NOBLET J. 2000. Voluntary feed intake and feeding behaviour of group-housed growing pigs are affected by ambient temperature and body weight. Livestock Production Science 63(1): 245–253.
QU H, DONKIN SS, AJUWON KM. 2015. Heat stress enhances adipogenic differentiation of subcutaneous fat depot-derived porcine stromovascular cells. J Anim Sci. 93(8): 3832–42. doi:10.2527/jas.2015-9074
RENAUDEAU D. 2004. Effects of short term-exposure to high ambient temperature and relative humidity on thermoregulatory responses of European (Large White) and Caribbean (Creole) restrictively-fed growing pigs. Anim. Res. 54: 81–93.
RENAUDEAU D, COLLIN A, YAHAV S, DE BASILIO V, GOURDINE JL, COLLIER RJ. 2012. Adaptation to hot climate and strategies to alleviate heat stress in livestock production. Animal 6(5): 707–728. doi:10.1017/S1751731111002448
ROBERTSHAW D. 2004. Temperature regulation and the thermal environment. Duke's Physiology of Domestic Animals. p. 962–973.
ROZEBOOM J, TODD S, FLOWERS W. 2000. Management Practices to Reduce the Impact of Seasonal Infertility on Sow Herd Productivity. ANS00-813S. North Carolina Cooperative Extension Service. Retrieved from Retrieved on 15 Jun 2015.
SIMONSEN HB. 1990. Behaviour and distribution of fattening pigs in the multi-activity pen. Applied Animal Behaviour Science 27(4): 311–324.
WALTZ X, BAILLOT M, CONNES P, BOCAGE B, RENAUDEAU D. 2014. Effects of Hydration Level and Heat Stress on Thermoregulatory Responses, Hematological and Blood Rheological Properties in Growing Pigs. PLoS ONE 9(7): 102537. Retrieved from on 15 Jun 2015.