Correlation of rectal temperature and peripheral temperature from implantable radio-frequency microchips in Holstein steers challenged with lipopolysaccharide under thermoneutral and high ambient temperatures1

Abstract

Early detection of disease can speed treatment, slow spread of disease in a herd, and improve health status of animals. Immune stimulation increases rectal temperature (RT). Injectable radio-frequency implants (RFI) can provide temperature at the site of implantation. The fidelity of peripheral site temperature, determined by RFI, relative to RT is unknown in cattle. We hypothesized that during lipopolysaccharide (LPS) challenge, temperature at 3 peripheral sites would be similar to RT in steers (n = 4; BW 77 ± 2.1 kg). The 3 sites were 1) subcutaneous (SC) at the base of the ear (ET); 2) SC posterior to the poll (PT); and 3) SC beneath the umbilical fold (UT). Steers were housed in controlled temperature (CT) rooms (between 18 and 21°C; n = 2/room). Rectal temperature, ET, PT, and UT were recorded every 8 h daily. On d 7, 21, 22, 36, and 37, RT and RFI were taken every 5 min for 6 h, every 15 min for 3 h, and every 30 min for 15 h. To test RFI during a simulated immune challenge, LPS (E. coli 055:B5) was injected intravenously (i.v.) at 1000 h on d 22 and 37. Basal temperatures (°C) were RT (38.7 ± 0.20), ET (37.1 ± 0.86), PT (36.7 ± 0.57), and UT (36.3 ± 0.97). Rectal temperature increased to 39.9 ± 0.30°C after LPS, but ET, PT, and UT decreased. Heat stress also increases RT, which makes it difficult to identify sick animals using RT. The second hypothesis tested was that ET positively correlates to RT and negatively correlates to RT during LPS under heat stress. Four steers (127 ± 7.3 kg) were housed in CT chambers (n = 2/chamber), implanted with a RFI, and allowed 2 wk to acclimate. One chamber remained at 20°C, the other was increased to 34°C starting at 0800 h for a period of 48 h. The LPS was administered i.v. to all steers at 1000 h on d 2. After a 2-wk recovery at 20°C, the temperature was increased in the other chamber, resulting in a crossover design with each steer serving as its own control. Pearson's correlation coefficients for ET and RT were 0.30 (P < 0.01) during heat stress, 0.20 (P < 0.05) during heat stress with LPS challenge, 0.34 (P < 0.01) during thermoneutrality, and -0.42 (P < 0.01) during thermoneutrality with LPS. These data refute the hypothesis that RT and peripheral temperature move in synchrony after LPS challenge. These data suggest that individual response be considered when identifying models for use of ET, but these RFI have potential for use in the early detection of diseases that alter basal temperature.

A Review of Methods to Measure Animal Body Temperature in Precision Farming

“…In goats exposed to different environmental conditions, the temperature measured by microchips implanted at various body locations differed from core temperature (Torrao et al, 2011). Similar results are obtained in steers by Reid et al (2012), (Table 4). …”

The Intimin-Like Protein FdeC Is Regulated by H-NS and Temperature in Enterohemorrhagic Escherichia coli

“…EHEC strains are zoonotic pathogens that colonize the terminal rectums of cattle and other ruminants, where the normal temperature is approximately 39°C (42). It has also been demonstrated that the rectal temperature of cattle can rise to around 41°C when cattle are exposed to high ambient temperatures (43).…”

Recent Advances on Early Detection of Heat Strain in Dairy Cows Using Animal-Based Indicators: A Review

“…In general, measuring temperatures subcutaneously requires the use of implantable sensors and wireless transmission. The ST can vary among different implantation locations and many efforts have been made to determine the best locations for measuring accurate CBT in cattle [40,90,91]. Reid et al [91] used implantable radiofrequency identification (RFID) microchips measuring temperature in three sites, subcutaneously at the base of the ear, posterior to the poll, and beneath the umbilical fold.…”

“…The ST can vary among different implantation locations and many efforts have been made to determine the best locations for measuring accurate CBT in cattle [40,90,91]. Reid et al [91] used implantable radiofrequency identification (RFID) microchips measuring temperature in three sites, subcutaneously at the base of the ear, posterior to the poll, and beneath the umbilical fold. They demonstrated that the temperatures at the base of the ear correlated most with RT with coefficients of 0.30 during heat stress and 0.20 during TNZ.…”