Sun Sik Chang

Effects of Ad libitum and Restricted Feeding of Concentrates on Body Weight Gain, Feed Intake and Blood Metabolites of Hanwoo Steers at Various Growth Stages

E.G.Kwon,S.K.Hong,H.H.Seong,S.G.Yun,B.K.Park,Y.M.Cho,W.M.Cho,S.S.Chang,K.J.ShinandB.H.PaekNationalLivestockResearchInstitute,R.D.A.ABSTRACTTwo hundred fifty eight Hanwoo steers were used in a completely randomized design experiment todetermine the effects of ad libitum or restricted feeding of concentrates on body weight(BW) gain, feedintake, blood metabolites and hematological parameters. Steers were assigned at 6 months of age tofeeding groups of adlibitum (T1) or restricted(T2)by 18 months of age. Steers in both groups were fedadlibitum from 19 months of age. The restrictive feeding levels were 1.2~1.5% of BW for the growingperiod and 1.7~1.8% of BW for the early fattening period. Average daily gains were significantly higherinT1 thanin T2from 10 to 14 monthsofage,butwere significantly higherinT2 thanin T1from 20to 24 months of age(p<0.05). Total dry matter intake(DMI) was higherin T1 than in T2 at 10, 12 and16 months of age(p<0.05). Total DMI of T2 was higher than that of T1 at 22 months of age(p<0.05).FeedconversionsweresignificantlylowerinT2thaninT1from20to30monthsofage(p<0.05).Bloodalbumin concentrations were significantly higher in T2 than in T1 at 12, 14, 16 and 18 months of age.Blood triglyceride concentrations were significantly higher in T1 than in T2 at14 and 16 monthsof age(p<0.05). Blood inorganic phosphorus concentrations were significantly higher in T2 compared with T1 at8, 10, 16 and 22 months of age(p<0.05). Mean corpuscular volume and mean corpuscular hemoglobinwere significantly lower in T2 than in T1 from 8 to 12 months of age(p<0.05), but those weresignificantly higher in T2 than T1 from 10 months to 12 months of age(p<0.05). Present results mayindicate that the restricted feeding for the growing period does not show adverse effects on body weightgainwithbetterfeedconversionforthefollowinglatefatteningperiod.(Keywords :Hanwoosteers, Adlibitum ,Restricted,Feedconversion,Bloodmetabolites)

Effects of concentrate feeding method and slaughter age on growth performance, feed intake and carcass characteristics of Hanwoo steers.

Young Moo Cho, Sun Sik Chang, Hyeong Cheol Kim, Tae Il Kim, Byung Ki Park, Bong Hyun Paek, Jin Hyoung Kimand Eung Gi KwonNational Institute of Animal Science, RDAABSTRACTThirty one Hanwoo steers were used in a completely randomized design experiment to see the effects of concentrate feeding method(group vs. individual feeding) and age at slaughter(26 vs. 28 months of age) on growth performance, feed intake and carcass characteristics. Steers were randomly assigned to one of four groups, G26(group feeding slaughtered at 26 months of age), G28(group feeding slaughtered at 28 months of age), I26(individual feeding slaughtered at 26 months of age) or I28(individual feeding slaughtered at 28 months of age). Amount of concentrate were restricted to 1.5% of BW for the growing period and 1.8% of BW for the early fattening period in both groups. For the late fattening period, concentrate were given ad libitum for G26 and G28, but were given up to 1.7% of BW for I26 and I28. Average daily gains were higher in individual feeding groups (I26 and I28) than those in group feeding groups(G26 and G28) for the early fattening period(p<0.05). ADGs were higher in group feeding groups than those in individual feeding groups (p<0.05). Concentrate intake in individual feeding groups tended to be higher compared to that in group feeding groups for the early fattening period, but tended to be higher in group feeding groups compared to that in individual feeding groups for the late fattening period. Feeding method or slaughter age had no significant effects on carcass characteristics, yield grade and quality grade. Shear force and tenderness of longissmus muscle were higher in groups slaughtered at 28 months of age than in groups slaughtered at 26 months of age(p<0.05). Feeding method or slaughter age had no effects on cooking loss, water holding capacity, juiciness, flavor, moisture, protein and fat of longissmus muscle. (Key words :Hanwoo steer, Feeding method, Age at slaughter, Carcass characteristics)

Effects of ruminally protected amino acid-enriched fatty acids on growth performance and carcass characteristics of fattening Hanwoo cows.

ABSTRACT This study was conducted to determine the effects of ruminally protected amino acid-enriched fatty acids (RPAAFA) on bodyweight gain, feed intake and carcass characteristics of fattening Hanwoo cows. Twenty eight Hanwoo cows, 6.0±1.7 years old andweighing an average of 463.2±77.6 kg, were used for 4 months. Animals were fed a basal diet supplemented with RPAAFA at 0g (control) and 100 g (treatment), respectively. Average daily gain, dry matter intake and feed conversion ratio were not differentamong the control and treatment. The supplementation of RPAAFA did not affect carcass weight and rib eye areas. Quality gradescore (1 ++ ,1 + and 1) for treatment was higher in RPAAFA supplemented group compared with the control, whereas no differencesappeared in meat color, fat color, texture and maturity. Thus present results indicate that supplementation of RPAAFA may berecommended for producing high quality beef from fattening Hanwoo cows.( Key words : Hanwoo cows, Ruminally protected amino acid-enriched fatty acids, Carcass characteristics, Beef fattening)

Effects of Total Mixed Rations on Growth Performance and Carcass Characteristics of Hanwoo Steers

ABSTRACT To investigate the effects of total mixed ration (TMR) on growth performance and carcass characteristics of Hanwoo steers, sixty steers were randomly assigned to one of four treatment groups; separate feeding of concentrate and rice straw (control), wet TMR (TMR), dry TMR with 20% (TMR) and 40% (TMR) barley bran from 6 to 28 month of age. In growth performance, average daily gains of TMRgroup was the highest (0.70 kg/day) but significant differences between treatments were not found (p>0.05). Average feed required for kg body weight gain of control group was 11.63kg. Those of TMRthrough TMRwere 9.29, 10.46 and 10.71 kg, respectively. Dressing percentage and retailed cut percentage were 59% and 63%, without any significant differences between treatments (p>0.05). There were no significant differences in rib-eye area, back fat thickness, meat color and fat color (p>0.05). Average marbling score was higher(p<0.05) in TMRthan in control group.( Key words : Total mixed ration, Hanwoo steer, Carcass characteristics, Economic efficacy)

Soluble Non-ammonia Nitrogen in Ruminal and Omasal Digesta of Korean Native Steers Supplemented with Soluble Proteins

An experiment was conducted to study the effect of soluble protein supplements on concentration of soluble non-ammonia nitrogen (SNAN) in the liquid phase of ruminal (RD) and omasal digesta (OD) of Korean native steers, and to investigate diurnal pattern in SNAN concentration in RD and OD. Three ruminally cannulated Korean native steers in a 3×3 Latin square design consumed a basal diet of rice straw and corn-based concentrate (control), and that supplemented (kg/d DM basis) with intact casein (0.24; IC) or acid hydrolyzed casein (0.46; AHC). Ruminal digesta was sampled using a vacuum pump, whereas OD was collected using an omasal sampling system at 2.0 h intervals after a morning feeding. The SNAN fractions (free amino acid (AA), peptide and soluble protein) in RD and OD were assessed using the ninhydrin assay. Concentrations of free AA and total SNAN in RD were significantly (p<0.05) lower than those in OD. Although free AA concentration was relatively high, mean peptide was quantitatively the most important fraction of total SNAN in both RD and OD, indicating that degradation of peptide to AA rather than hydrolysis of soluble protein to peptide or deamination may be the most limiting step in rumen proteolysis of Korean native steers. Diurnal variation in peptide concentration in OD for the soluble protein supplemented diets during the feeding cycle peaked 2 h post-feeding and decreased thereafter whereas that for the control was relatively constant during the entire feeding cycle. Diurnal variation in peptide concentration was rather similar between RD and OD.

Effects of Brewers Grain, Soybean Curd and Rice Straw as an Ingredient of TMR on Growth Performance, Serum Parameters and Carcass Characteristics of Hanwoo Steers

본 연구는 맥주박, 비지박 및 볏짚을 각각 이용하여 배합한 TMR을 한우 거세우에게 급여하였을 때 사양성적, 혈액성상 및 도체특성을 구명하고자 수행되었다. 시험구는 6개월령 한우 거세우 24두(평균체중 168 kg)를 배합사료 볏짚 분리급여구(T1), 맥주박 첨가 TMR 급여구(T2), 비지박 첨가 TMR 급여구(T3) 및 볏짚 첨가 T...

Effects of Feeding Patterns of Concentrate on Growth Performance, Blood Parameters and Carcass Characteristics in Fattening Hanwoo Cows

Division of Applied Life Science, Graduate School Gyeongsang National University, Jinju, 660-701, KoreaABSTRACTThis study was conducted to investigate the effects of feeding patterns of concentrates on growth performance, blood parameters and carcass characteristics in Hanwoo cows. Randomly-allocated groups, restricted concentrate feeding(T1), restricted concentrate feeding for 6 months and ad libitum 2 months(T2), restricted concentrate feeding for 4 months and ad libitum 4 months(T3), were contained with 9 animals. According to feeding patterns of concentrate, growth performance was not significantly different among the treatment groups. However, ADG tended to be higher in T2 group(0.75kg/d) compared to the other groups (T1: 0.62 kg/d, T3: 0.72kg/d). DMI was not significantly different among the treatment groups, interestingly, rice straw intake was significantly higher in T1 group compared with others(p<0.05). There were significant difference among feed conversion ratio, which are 17.8, 12.8, and 14.1 kg for T1, T2, and T3(p<0.05), respectively. The serum level of albumin, triglyceride, glucose and GPT were greater in T3 group compared to other groups at fattening 6 to 8 months(p<0.05). The results of yield traits, carcass weight, back fat thickness and rib eye area were not differ among treatment groups, but yield index was significantly greater in T2 group compared to T1 group(p<0.05). The ‘A’ appearance rate(%) of meat yield grade was highest in T2 group for 78%. The marbling score, meat color, fat color, texture and maturity in quality traits were not differ among the treatment groups. However, marbling score and appearance rate(%) of over 1st meat quality grade were tend to be increased at T3 rather (4.0, 56%) group compared with other groups(T1: 3.4, 56%; T2: 3.6, 33%). Thus, the present study suggested that restricted concentrate feeding(1.6% of BW) for 4 months during early fattening periods and ad libitum feeding for 4 months during late fattening periods are recommendable.(Key words : Hanwoo Cow, Concentrate, Growth performance, Carcass characteristics, Blood parameters)

Effects of Reed (Phragmites communis) on Growth Performance, Carcass Characteristics, and Meat Quality in Hanwoo Steers

This study investigated the effects of diet of different forages on growth performance and carcass characteristics of Hanwoo steers. Twenty-one Hanwoo steers were randomly allocated to three groups (fed hay, reed, and reed with rice straw) of seven steers each. Initial and final body weights of control, T1, and T2 groups were 125.5, 128.3, 128.3 kg and 697.4, 614.6, 706.7 kg, respectively. Average daily gain tended to increase in controls (0.70 kg/d) and the T2 group (0.71 kg/d) but not as much in the T1 group (0.60 kg/d); however, there was no significant difference. DMI was not significantly different among the treatment groups, but T1 was relatively lower than the other groups. For the yield traits, carcass weight was not significantly different between controls and the T2 group but was greater in the T2 group compared to the T1 group (p the other groups (control 0:71:29; T2 29:42:29). For the quality traits, fat color and texture were not significantly different among groups. However, meat color and maturity were significantly greater in T1 compared to T2 (p feed utilization, and carcass traits appeared to improve when roughage containing rice straw plus reed was offered. Therefore, reed is worth considering as a roughage source for fattening Hanwoo steers.

Effect of Seeding Rates of Cold Tolerant Italian Ryegrass Varieties on Those Seed Production

ABSTRACTThis experiment was carried out to investigate the effect of seeding rate of newly developed Italian ryegrass varieties, “Kogreen” and “Hwasan 101”, on those seed production in Cheonan for three years (2005 to 2007). Two Italian ryegrass varieties were seeded at experimental fields of Grassland and Forage Division, National Institute of Animal Science on late September, and harvested at seed shattering stage. The experiment was arranged in randomized complete block design with three replications by each variety. The treatments was consisted of five seeding rates(5, 10, 20, 30, 40kg/ha). The average heading date of “Kogreen” was 9 May and “Hwasan 101” was 25 May. The harvesting date of “Kogreen” was on 16 June when the rainy season should not set in. In the case of “Hwasan 101”, the harvesting date of seed production was 3 July, because of rainy season. The number of ear per square meter, ear length, spikelet number, seed yield per ha and ripening rate of “Hwasan 101” were 471, 28.5cm, 24.8, 1,631kg and 71%, respectively. and those of “Kogreen” were 633, 24.0cm, 20.8, 2,676kg and 82.1%, respectively. The shattering property rate of “Hwasan 101” 40.3% was higher than that of “Kogreen” 2.6%. The germination rate of harvested “Hwasan 101” seed was 81.8% and that of “Kogreen” was 79.4%, respectively. In conclusion, the optimum seeding rate of Italian ryegrass for seed production are recommended 20kg/ha in both “Hwasan 101” and “Kogreen”.(Key words: Hwasan 101, Kogreen, Seed yield, Germination, Seed amount)