• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1117-1123
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• 2017

Objective: This study was conducted to compare growth performance, blood components and carcass traits by two feeding systems (concentrate with roughage separately [CON] vs total mixed ration [TMR]) in Hanwoo steers, and to learn the relationship between blood components during fattening or finishing phases and carcass traits in Hanwoo steers. Methods: Sixty steers aged 8 months were allotted to two feeding systems and fed similar amounts of average dry matter and total digestible nutrient throughout whole experimental period according to each feeding program. Steers were weighed monthly, taken blood at the end of growing, fattening and finishing periods, and slaughtered at 30 month of age. Results: Growing performance was higher (p<0.05) in the CON group compared to the TMR group during fattening and finishing periods. The CON group was lower (p<0.05) in blood aspartic acid transaminase, blood urea nitrogen and retinol levels during growing period, but higher in triglyceride and cholesterol levels during fattening and finishing periods compared to the TMR group. The CON group was greater (p<0.05) in rib-eye area, and lighter (p<0.05) red in meat color compared to the TMR group. In the correlation coefficients between blood components of steers and carcass traits, retinol had a negative (p<0.05) correlation with marbling score and rib-eye area. Leptin had a positive (p<0.05) correlation with back fat thickness. Blood cholesterol and triglyceride were positively (p<0.05) correlated with carcass weight and rib-eye area. Conclusion: Growth performance, carcass ribeye area and meat color showed a more desirable result in the CON compared to the TMR in Hanwoo steers. Assessing the accumulated data of carcass traits with blood components including hormones-particularly retinol, cholesterol, triglyceride, and leptin-during the fattening or finishing phases, it may be possible to find a biomarker for determining beef quality in living animals.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.6
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• pp.800-807
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• 2019

Objective: The aim was to evaluate backgrounding beef steers on oat + ryegrass pastures mixed with vetch and/or using energy supplementation. Methods: A randomized block design with three treatments and three replications was used. The treatments were: grass + supplement (oat + ryegrass + supplementation), legume + supplement (oat + ryegrass + vetch + supplementation) and grass + legume (oat + ryegrass + vetch). A continuous grazing system with a variable stocking rate was used. Twenty-seven intact crossbred steers (1/4 Marchigiana, 1/4 Aberdeen Angus and 2/4 Nellore) aged 7 months old and average weight of 190 kg were used. Steers were supplemented at 1% of the body weight of ground corn. The experiment lasted 84 days, between May and August 2014. Behavioral assessments were performed two times per experimental period, for 24 hours. Results: The forage mass was different between treatments, being greater for steers fed without legume. The accumulation rate, forage allowance, and stocking rate did not differ between treatments due to the adequate adjustment of forage allowance. The final weight of animals, as well as the dry matter intake (kg/d), did not differ between treatments. However, forage intake was higher for non-supplemented animals in relation to supplemented steers. Supplement intake did not alter the total digestible nutrient intake due to pasture quality. Animals fed grass + supplement had higher live weight gain per area than those fed grass + legume. Animals without supplementation spent more time in grazing. Conclusion: Feeding behavior was not altered by mixing with vetch or supplementation. Non-supplemented animals started the grazing peak earlier and spent more time in grazing than those supplemented; however, the average daily gain was similar between treatments. The live weight gain per hectare was 47% higher in pastures in which the animals received supplementation compared with those mixed with vetch, a consequence of the substitutive effect.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.12-16
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• 2015

This study was carried out to evaluate accurately physical characteristics of total mixed rations (TMR) by investigating the effects of physically effective neutral detergent fiber content on the growth performance and carcass characteristics in fattening steers. Twelve Hanwoo (Bos Taurus coreanae) steers aged 26 months were used in this trial. Steers were offered one of two total mixed ration (TMR) diets - High or Low physically effective neutral detergent fiber (peNDF) content groups-that were differentiated by mixing time. The carcass traits of the experimental animals were evaluated by Korea Institute for Animal Products Quality Evaluation (KAPE) after slaughter. Body weight gain during the experimental period was significantly higher (P<0.05) in the High group ($30.00{\pm}10.27kg$) compared with the Low group ($17.20{\pm}6.34kg$), and daily weight gain was also high in the former. Although there was no significant difference, the carcass weight was higher in the High group ($414.60{\pm}34.28kg$) compared with the Low group ($377.80{\pm}11.97kg$). However, the beef quality grade of the Low group ($1^{++}$) was higher than that of the High group ($1^+$). Increases in body weight gain, daily gain, and carcass weight for the High group were mainly influenced by a high level of dry matter (DM) intake and digestibility; consequently, back-fat thickness increased and the beef quality grade was lowered. Because growth performance and carcass characteristics were affected by the physical traits of the diet, we suggested that proper peNDF content is also needed for fattening steers.