Article

Effect of fattening period on growth performance, carcass characteristics, and economic traits of Holstein steers

Sung Il Kim1,*, Sungkwon Park2, Jung Hwan Myung3, Young Min Jo4, Chang Bon choi4, Keun Ki Jung5
Author Information & Copyright
1Department of Animal Science, Gyeongbuk Provincial College, Yecheon 36830, Korea.
2Department of Food Science and Biotechnology, Sejong University, Seoul 05006, Korea.
3Deahan Livestock & Feed Co., Incheon 22300, Korea.
4Department of Biotechnology, Yeungnam University, gyeongsan 38541, Korea.
5Moksan Hanwoo Research Institute, gyeongsan 38507, Korea.
*Corresponding Author: Sung Il Kim, Department of Animal Science, Gyeongbuk Provincial College, Yecheon 36830, Korea, Republic of. Phone: +82-54-650-0341. E-mail: ksi-30@hanmail.net.

© Copyright 2021 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.

Received: Apr 07, 2021; Revised: May 21, 2021; Accepted: Jun 15, 2021

Published Online: Jul 26, 2021

Abstract

This study was conducted to investigate the effect of different fattening periods on the growth performance, carcass characteristics, and economic traits of Holstein steers. Sixty Holstein steers (8.0 ± 0.28 months old) with an average body weight (BW) of 231.88 ± 2.61 kg, were randomly allocated to five different fattening period treatments: 20, 21, 22, 23, and 24 months (n = 12 in each treatment group). Final BW and average daily gain (ADG) did not differ among the treatment groups during the early fattening period. At the late stage of the fattening period, the final BW of steers in the 24-month treatment group (812.84 kg) was greater (<italic>p</italic> &lt; 0.05) than that of steers in the 20-month treatment group (750.39 kg). During the same period, steers in the 20- and 21-month treatment groups had a significantly higher (<italic>p</italic> &lt; 0.05) ADG than those in the 22-month treatment group. The highest ADG (1.36 kg/day) was found in the 20-month treatment group (1.36), followed by the 21- (1.33 kg/day), 22- (1.22 kg/day), 23- (1.21 kg/day), and 24- (1.14 kg/day) month treatment groups. The feed conversion ratio (FCR) increased as the fattening period increased, and the FCR was 12.88% lower in the 20-month treatment group than in the 24-month treatment group. However, no significant differences were detected in back-fat thickness, loin area, marbling score, and chemical characteristics (water, crude protein, and crude fat content) among the treatment groups. The composition of fatty acids including C18:0, C18:1, saturated fatty acids, unsaturated fatty acids, and poly-unsaturated fatty acids did not differ among the experimental groups. As the fattening period increased, production costs increased, resulting in a decrease in gross income. The gross income for steers in the 24-month treatment group was 35.8% and 23.5% lower than that for steers in the 20- and 21-month treatment groups, respectively. Taken together, the best performance, including the ADG, FCR, and gross income, was obtained when the fattening program of the Holstein steers lasted 20 months.

Keywords: Holstein; steer; carcass characteristics; gross income; fattening; performance