Plasticity of feeding behaviour traits in response to production environment (temperate vs. tropical) in group-housed growing pigs

Abstract

Heat stress affects pig metabolism, health and welfare, resulting in reduced growth and important economic losses. The present experiment aimed to evaluate the effects of two climatic environments [temperate (TEMP) vs. tropical humid (TROP)] on feeding behaviour in growing pigs. The feeding behaviour traits were measured with automated feeders and included: daily feed intake, daily eating time, feeding rate, daily number of meals, feed intake per meal, and feeding time per meal. Pigs came from a backcross population between Large White (LW, heat sensitive) and Creole (CR, heat tolerant) pigs. The same 10 F1 LW × CR boars (sire families [SF]) were mated with related LW sows in each environment. Feeding behaviour was recorded for a total of 1,296 pigs (n = 634 pigs for TEMP and n = 662 pigs for TROP) between 11 and 23 weeks of age. Growth performance and thermoregulatory responses (rectal and skin temperatures) were also measured. Results show that TROP conditions affect feeding behaviour traits: animals had more meals per day but these meals were smaller both in duration and in size, resulting in lower daily feed intake and less time eating per day. Significant SF by environment (GxE) interactions were found for all feeding behaviour traits. When SF were distributed into robust and sensitive groups (previously defined according to performance and thermoregulatory traits), results showed group by environment interactions for all feeding traits, except meal frequency. Moreover, a significant difference in feeding rate between robust and sensitive group was detected in TEMP, suggesting that feeding rate may be a good candidate to evaluate heat tolerance.

Effect of ambient temperature on average daily gain of pigs evaluated using public weather data and a plateau‐linear regression model

“…Recently, it has been suggested that heat stress has various effects on pigs at the transcriptome and proteome levels (e.g., He et al, 2020 ; Pearce et al, 2015 ; Zhao et al, 2021 ) and that heat stress might have multi‐generational effects (Johnson et al, 2020 ). Studies to identify indicators of heat stress (e.g., Cross et al, 2018 ; Gourdine et al, 2019 ; Poullet et al, 2022 ) and those for predicting breeding values for heat tolerance using public weather data (e.g., Tiezzi et al, 2020 ; Usala et al, 2021 ; Zumbach et al, 2008 ) have also been performed. Thus, developing methodology to genetically improve pigs to cope with climate change would be valuable (e.g., Gourdine et al, 2021 ; Hara et al, 2022 ; Ogawa, Kimata, et al, 2022 ).…”

Alleviating Heat Stress in Fattening Pigs: Low-Intensity Showers in Critical Hours Alter Body External Temperature, Feeding Pattern, Carcass Composition, and Meat Quality Characteristics

“…According to Poullet et al [ 30 ], the upper limit of thermoneutrality, in which no extra energy is used for thermoregulation, ranges between 20 °C and 25 °C for growing–finishing pigs.…”

“…Reduced FI and increased body temperature have been widely described as related to HS. In terms of feeding behavior, the animals have more meals per day, but of shorter duration and in smaller quantities, a nibbling/slow eating pattern [ 4 , 5 , 30 , 33 ].…”