Article

Increased accuracy of estrus prediction using ruminoreticular biocapsule sensors in Hanwoo (Bos taurus coreanae) cows

Daehyun Kim1, Woo-Sung Kwon2, Jaejung Ha1, Joonho Moon3,*, Junkoo Yi1,**
Author Information & Copyright
1Livestock Research Institute, 186, Daeryongsan-ro, Anjeong-myeon, Yeongju-si, Gyeongsangbuk-do 36052, Korea.
2Department of Animal Science and Biotechnology, Kyungpook National University, 2559, Gyeongsang-daero, Sangju-si, Gyeongsangbuk-do 37224, Korea.
3GenNBio Co., Ltd., 166, Cheongbuksandan-ro, Cheongbuk-eup, Pyeongtake-si, Gyeonggi-do 17792, Korea.
**Corresponding Author: Joonho Moon, GenNBio Co., Ltd., 166, Cheongbuksandan-ro, Cheongbuk-eup, Pyeongtake-si, Gyeonggi-do 17792, Korea, Republic of. E-mail: kuma618@gmail.com.
**Corresponding Author: Junkoo Yi, Livestock Research Institute, 186, Daeryongsan-ro, Anjeong-myeon, Yeongju-si, Gyeongsangbuk-do 36052, Korea, Republic of. E-mail: 79lee38@korea.kr.

© Copyright 2023 Korean Society of Animal Science and Technology. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Visual estrus observation can only be confirmed at a rate of 50%–60%, which is lower than that obtained using a biosensor. Thus, the use of biosensors provides more opportunities for artificial insemination because it is easier to confirm estrus  than by visual observation. This study determines the accuracy of estrus prediction using a ruminoreticular biosensor by analyzing ruminoreticular temperature during the estrus cycle and measuring changes in body activity. One hundred and twenty-five Hanwoo cows (64 with a ruminal biosensor in the test group and 61 without biosensors in the control group) were studied. Ruminoreticular temperatures and body activities were measured every 10 min. The first service of artificial insemination used gonadotropin-releasing hormone (GnRH)-based fixed-time artificial insemination protocol in the control and test groups. The test group received artificial insemination based on the estrus prediction made by the biosensor, and the control group received artificial insemination according to visual estrus observation. Before artificial insemination, the ruminoreticular temperature was maintained at an average of 38.95 ± 0.05°C for 13 h (−21 to −9 h), 0.73°C higher than the average temperature observed at −48 h (38.22 ± 0.06°C). The body activity, measured using an indwelling 3-axis accelerometer, averaged 1502.57 ± 27.35 for approximately 21 h from −4 to −24 h before artificial insemination, showing 203 indexes higher body activity than −48 hours (1299 ± 9.72). Therefore, using an information and communication techonology (ICT)-based biosensor is highly effective because it can reduce the reproductive cost of a farm by accurately detecting estrus and increasing the rate of estrus confirmation in cattle.

Keywords: ruminoreticular biocapsule sensor; ruminoreticular temperature; body activity; estrus detection; conception rate; Hanwoo