Comparison of different anatomical sites for monitoring body temperature in cattle and sheep : A dissertation submitted in partial fulfilment of the requirements for the degree of Bachelor of Science with Honours at Lincoln University

Abstract

This study was conducted to investigate whether the vaginal temperature of cattle and sheep reflects core body temperature as measured at the rectum, mainly because there is little evidence available in the scientific literature on which to draw a firm conclusion. Ruminal temperature was recorded to provide a comparative measurement that is known to differ occasionally from core body temperature. Four experiments were conducted that used a temperature sensor and data logger to provide simultaneous recordings: (1) vaginal, rectal and ruminal temperatures of sheep (n = 4, 2 runs) and cattle (n = 2, 2 runs) were measured for 4 h and 2.5 h respectively; (2) vaginal, rectal and ruminal temperatures of sheep (n = 4) and cattle (n = 2) were measured for 1.5 h, then the animals received 0.8 μg/kg and 0.2 μg/kg live weight, respectively, of endotoxin and were monitored for a further 4 h; (3) vaginal and rectal temperatures of sheep (n = 8) were recorded for 2 h; (4) vaginal temperatures of 6 sheep and rectal temperatures of 12 sheep were recorded for 4 h. The results showed that rectal and vaginal temperatures did not differ in both species (P = 0.07 to 0.81 in sheep and P =0.67 to 0.68 in cattle). In sheep, normal means (± SEM) of rectal and vaginal temperature ranged between 39.1 °C and 39.4 °C (± 0.04 to 0.11) and 39.2 °C and 39.5°C (± 0.07 to 0.17) °C, respectively. In cattle, the means (± SEM) of normal rectal and vaginal temperatures were 38.6 ± 0.10 °C and 38.6 ± 0.07 °C, respectively. Mean normal ruminal temperature was 39.8 ± 0.16 °C in sheep and 39.2 ± 0.18 °C in cattle. Temperatures were elevated approximately 2 °C following administration of endotoxin in both species and this did not cause rectal and vaginal temperature to deviate from each other. Ruminal temperature varied (P < 0.05) by up to 1.5 °C from rectal and vaginal temperatures in both species and in one sheep a fall in both ruminal and rectal temperatures by 1.9 °C and 0.8 °C was caused by ingestion of water. The findings from the present study indicate that for monitoring body temperature, vaginal temperature is equivalent to rectal temperature. Also, they provide further support for other studies which have shown that ruminal temperature can vary independently of core body temperature.