title: Body Temperature Monitoring Using Subcutaneously Implanted Thermo-loggers from Holstein Steers.
abstract: Body temperature (BT) monitoring in cattle could be used to early detect fever from infectious disease or physiological events. Various ways to measure BT have been applied at different locations on cattle including rectum, reticulum, milk, subcutis and ear canal. In other to evaluate the temperature stability and reliability of subcutaneous temperature (ST) in highly fluctuating field conditions for continuous BT monitoring, long term ST profiles were collected and analyzed from cattle in autumn/winter and summer season by surgically implanted thermo-logger devices. Purposes of this study were to assess ST in the field condition as a reference BT and to determine any location effect of implantation on ST profile. In results, ST profile in cattle showed a clear circadian rhythm with daily lowest at 05:00 to 07:00 AM and highest around midnight and rather stable temperature readings (mean±standard deviation [SD], 37.1°C to 37.36°C±0.91°C to 1.02°C). STs are 1.39°C to 1.65°C lower than the rectal temperature and sometimes showed an irregular temperature drop below the normal physiologic one: 19.4% or 36.4% of 54,192 readings were below 36.5°C or 37°C, respectively. Thus, for BT monitoring purposes in a fever-alarming-system, a correction algorithm is necessary to remove the influences of ambient temperature and animal resting behavior especially in winter time. One way to do this is simply discard outlier readings below 36.5°C or 37°C resulting in a much improved mean±SD of 37.6°C±0.64°C or 37.8°C±0.55°C, respectively. For location the upper scapula region seems the most reliable and convenient site for implantation of a thermo-sensor tag in terms of relatively low influence by ambient temperature and easy insertion compared to lower scapula or lateral neck.
authors.affiliation: Institute of Green-Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea.
authors.forename: Y
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Institute of Green-Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea.
authors.forename: J D
authors.initials: JD
authors.lastname: Bok
authors.affiliation: Institute of Green-Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea.
authors.forename: H J
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Department of Animal Science and Technology, Konkuk University, Seoul 05029, Korea.
authors.forename: H G
authors.initials: HG
authors.lastname: Lee
authors.affiliation: Institute of Green-Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea; College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea.
authors.forename: D
authors.initials: D
authors.lastname: Kim
authors.affiliation: Institute of Green-Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea; College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea.
authors.forename: I
authors.initials: I
authors.lastname: Lee
authors.affiliation: Institute of Green-Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea.
authors.forename: S K
authors.initials: SK
authors.lastname: Kang
authors.affiliation: Institute of Green-Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Choi
keywords: Cattle; Circadian Rhythm; Fever Detection; Subcutaneous Temperature; Thermo-logger