Infrared thermography as a possible technique for the estimation of parturition onset in sows

Abstract

Background This study explores the possibility of using infrared thermography to estimate the onset of parturition in sows. Infrared camera (IRC) and infrared laser thermometer (IRT) were used to obtain the auricular skin temperature of sows along with rectal temperatures, from approximately one week before the anticipated farrowing until 24 h post-partum. Three commercial piglet producing farms were included in the study. Results There were large variations in observed auricular skin temperature, both by IRC and IRT per time point. Graphical exploration of the observed auricular skin temperature measured by the two methods showed the same parallel patterns, although temperatures measured by IRC were higher at any time point compared to IRT. Auricular skin thermography revealed a clear increase in temperatures before farrowing. Statistical analyses, adjusting for differences between farms, sow activity and respiration rate, confirmed this increase. When controlling for these variables, and comparing the baseline temperatures to temperatures at farrowing, the difference was 3.9 and 4.1 °C measured with IRT and IRC, respectively. The greatest increase, of more than 2 °C, was found between 16 and 8 h and 8 to 4 h before farrowing. Rectal temperature increased by 0.5 °C in the same time interval and reached a temperature peak after farrowing. Conclusion Sows showed a more than 2 °C increase in auricular skin temperature, measured by either IRC or IRT, 8 to16 hours before the first piglet was born. Hence, monitoring auricular skin temperatures of sows using infrared thermography one week before expected farrowing may provide a baseline temperature for each sow from which a sudden rise is indicative of parturition in the following 8 to 16 h. This may lead to more efficient allocation of human assistance during farrowing time and thereby improve farrowing management and the welfare of sows and their offspring.

Instance Segmentation and Ensemble Learning for Automatic Temperature Detection in Multiparous Sows

“…(2) Pertaining to temperature prediction, a random forest algorithm, optimized by an adaptive genetic algorithm, constructs an inversion model based on environmental parameters, vulvar temperature, and rectal temperature, aspiring to predict the sows' temperature accurately. (3) In the context of practical farming, test results exhibit that the sow temperature monitoring method posited in this study can accurately predict the rectal temperature of sows in sheltered scenarios, thereby establishing a foundation for health monitoring and estrus detection in sows.…”

“…In light of the rapid advancement of automated temperature measurement technology, infrared thermography (IRT) imaging technology is progressively applied in large-scale sow management. Currently, researchers have embarked on studies related to sow lameness detection, farrowing prediction, febrile pig detection, metabolic function assessment in pigs, and early shoulder sore identification in sows, utilizing IRT imaging technology [2][3][4][5][6].…”

Physiology and management of the peri‐parturient sow in the context of changing production conditions

“…Preparturient sows also experience changes in thermoregulation and cardiovascular changes. A number of authors have reported an increase in rectal temperature (0.5–1.4°C) or skin temperature in the 12 h before farrowing (Gulliksen et al, 2023; Hendrix et al, 1978; Vermeer & van der Wilt, 1999), indicating increased heat production. In the same period, heart rate and respiratory rate also increase considerably (Gulliksen et al, 2023; Hendrix et al, 1978).…”

“…A number of authors have reported an increase in rectal temperature (0.5–1.4°C) or skin temperature in the 12 h before farrowing (Gulliksen et al, 2023; Hendrix et al, 1978; Vermeer & van der Wilt, 1999), indicating increased heat production. In the same period, heart rate and respiratory rate also increase considerably (Gulliksen et al, 2023; Hendrix et al, 1978). It is not clear what these changes reflect, although they may be related to the increased activity of the sow, with heat production associated with colostrum production (Theil et al, 2022), or possibly with the increase in uterine contractions in this period.…”

An Approach towards a Practicable Assessment of Neonatal Piglet Body Core Temperature Using Automatic Object Detection Based on Thermal Images

“…The BCT can be used as a hint for several diseases or hormonal changes, such as mastitis, metritis, and agalactia (MMA) [12], the onset of farrowing in sows [13], or, for example, classical fever in fattening pigs [1]. Further, thermal images were used to detect inflammation [14] and lesions [15], which are linked to isolated surface temperature deviations.…”