The efficiency of vaginal temperature measurement for detection of estrus in Japanese Black cows

Abstract

Recently, weak estrous behavior was assumed to be the cause of a decline in breeding efficiency in cattle. The present study investigated the effect of measuring the vaginal temperature on the detection of estrus in Japanese Black cows. First, the effect of hormone administration to cows with a functional corpus luteum on the vaginal temperature was evaluated by continuous measurement using a temperature data logger. After 24 h of cloprostenol (PG) treatment, the vaginal temperature was significantly lower than on day 7 after estrus, and the low values were maintained until the beginning of estrus (P < 0.05). The cows that received PG and exogenous progesterone (CIDR) did not show a temperature decrease until the CIDR was removed. This finding suggested that the vaginal temperature change reflected the progesterone concentration. The rate of detection of natural estrus was lower for a pedometer than for the vaginal temperature (P < 0.05); synchronization of estrus resulted in a high estrus detection rate regardless of the detection method. In a subsequent experiment, the effect of vaginal temperature measurement and the use of a pedometer on estrus detection was evaluated in the cool and hot seasons. The average activities during non-estrus and the activity increase ratio (estrus/non-estrus) changed according to season (P < 0.01, P < 0.05). However, the average vaginal temperatures during estrus and non-estrus were not affected by season. The estrus detection rate of the pedometer was lower in summer and lower than that obtained using the vaginal temperature. These results indicated that vaginal temperature measurement might be effective for detecting estrus regardless of estrous behavior.

Impaired reproduction in Japanese Black cattle under cold environmental conditions

“…However, during this extensive field study, heat stress was not found to have an effect on CRFA or CFAI, with CFAI tending to be longer during the cold season. Sakatani et al (2012) previously showed that heat stress did not have as strong an effect on rectal temperature in Japanese Black cattle than in certain dairy cows, such as Holstein Friesian, indicating that beef cattle are a thermotolerant breed (Sakatani, Takahashi, & Takenouchi, 2016).…”

“…Sakatani et al. () previously showed that heat stress did not have as strong an effect on rectal temperature in Japanese Black cattle than in certain dairy cows, such as Holstein Friesian, indicating that beef cattle are a thermotolerant breed (Sakatani, Takahashi, & Takenouchi, ). Thus, Japanese Black cattle appear to be more susceptible to the cold than to heat.…”

Efficiency of a pedometer device for detecting estrus in standing heat and silent heat in Japanese Black cattle

“…To calculate the estrus duration, the beginning of estrus (0 hr) was determined when the numbers of steps (/hr) became 1.5‐fold higher than the 14‐day average before estrus (steps/hr) and remained at this higher level for more than 3 hr (Sakatani, Balboula, Yamanaka, & Takahashi, ; Sakatani et al., ; Yoshioka et al., ). The end of estrus was defined as the time when the steps/hr returned to less than 1.5 times the 14‐day average level.…”

“…Thus, the detection of estrus by the measurement of steps is suitable from the standpoint of labor reduction and animal welfare. However, in some situations, such as in tiestalls or during the summer season, the activity and number of steps during estrus are difficult to detect, and so the effectiveness of detecting estrus by pedometer is limited (Sakatani, Takahashi, & Takenouchi, ).…”

Untitled

“…Pengukuran suhu vagina selama berahi telah dilaporkan bahwa peningkatan suhu tubuh berhubungan dengan hormon yang disekresikan selama berahi (Sakatani, Takahashi, and Takenouchi, 2016 …”