Electronic identification and monitoring of pigs during housing and transport

Abstract

Abstract Ear base and rectal temperatures of 21 individually housed multiparous sows were measured in order to detect oestrus for optimal insemination time. A thermistor was implanted in the ear base and wire-connected to a data-acquisition system, allowing time-sampling with a measuring accuracy of 0.1°C. Air temperature in the neighbourhood of the sows was measured with the same equipment. Rectal temperature was measured each day in the afternoon with a veterinary thermometer. Following the rectal temperature measurement, a blood sample was taken to determine oestradiol-17 β-content. The combination of the physiological measurement with the observation of the standing reflex of the sows made oestrus detection very reliable. A statistically significant rise of ear base (1.1 ± 0.12°C) and rectal (0.65 ± 0.3°C) temperature was observed 2 days before oestrus. A total of 45 pigs were transported at a body weight of about 20 kg. At 1 week before transport a telemetric device was injected in the base of each pig's ear. Transmission of information was received by an aerial, which was integrated in the floor of the trailer, and was connected to a receiver with data management facilities. Accuracy and resolution of measuring body temperature was 0.1°C. During transport a statistically significant increase of ear base temperature (about 0.7°C) was observed. Data collection efficiency was estimated at 30%.