Technology and application in automatic monitoring of the body temperature for livestock and poultry

Body temperature is an important physiological indicator to measure the health status of livestock and poultry. It is critical to a fast and accurate method of temperature measurement for disease monitoring and diagnosis. Some automatic temperature measurements can be expected to replace the traditional rectal temperature measurement commonly used in livestock and poultry production, due to the current time-consuming, laborious, and posture dependency. Usually, the rectal temperature cannot be directly taken by the automatic temperature measurement. It needs to collect the temperature of other body parts, and then establish the relationship with the rectal temperature for the core temperature. In this study, the automatic temperature measurement was divided into two types: the vivo and the vitro. A systematic review was also made of the technology and development history, in order to compare two types of temperature monitoring currently used in the livestock and poultry breeding industry (e.g., pig, cows, and chickens). An intelligent device (such as a capsule or chip) was normally implanted into an animal for long-term temperature monitoring in vivo temperature measurement, indicating the popular trend for high accuracy and stability. However, the invasive devices inevitably caused animal discomfort during the implantation process, which was harmful to animal welfare. In vitro detection was also divided into contact and non-contact temperature measurement. Specifically, the contact one was simple and easy to operate, but difficult to wear on the animal body, and highly sensitive to the complex environment of animal houses. The infrared-based temperature detection provided a non-invasive body surface temperature measurement, which was characterized by rapidity, high efficiency, and no stress. But, it was normally required for the temperature compensation between the body surface and thermal environment, due to the interference by environmental factors (e.g., temperature, humidity, CO2, light intensity, and ventilation). Therefore, the prediction model was mostly focused on the relationship between the core body temperature and measured temperature derived from the parameters. As such, these important points were necessary, whatever the automatic temperature measurement was used. It was a high demand to minimize the stress response of animals for the non-invasive monitoring of body temperature. A reliable prediction was then required to establish the monitoring temperature and the core temperature of animals. Correspondingly, the environment of livestock and poultry house was tunable controlled, as the changes in the monitoring temperature of animals. These methods have been widely used in animal farming for production performance, health, and behavior monitoring. Finally, the existing technology of automatic temperature measurement was summarized for the key points of improvement research. An emphasis was posed on the commonly-used infrared temperature measurement, due to its high efficiency, convenience, no stress, and easy detection of the automatic body temperature for animal groups or flocks. The infrared temperature measurement can be expected to dominate the promising research and application of body temperature monitoring on animal farms.