In-Sik Nam

Estimation of genetic characteristic and cumulative power of discrimination using the microsatellite markers in Korean Native Chicken.

To estimate the genetic characteristics and cumulative power of discrimination (CPD) Korean Native Chicken. We used a total of 195 genomic DNAs from four breeds population (Korean Native Red chicken: R, Korean Native Yellow chicken: Y, Korean Native Black chicken: L, Ogal chicken: S). Frequencies of microsatellites markers were used to estimate heterozygosities and genetic distances. The lowest distance (0.05) was observed between the R and L strains and the highest distance (0.158) between the L and S strains. Korean native chicken strains (R, Y, K) have each other comparatively near genetic distance. Cumulative power of discriminate (CPD) was 99.999% by including the 10 microsatellites loci individual identification system. And then matching probability in that two different individuals incidentally have same genotype was estimated to 0.36×10 -7 . The system employing

Effects of Different Levels of CP Intake on Protein Utilization and N Excretion in Varying Growth Stages of Hanwoo Steers

Three experiments with different stage of Hanwoo steers (average BW of 167 kg, 355 kg and 449 kg, respectively) were conducted to examine the effect of different quantities of CP intake with similar DM intake on protein balance and N excretion. Twelve Hanwoo steers in each experiment were offered three diets containing three levels of protein (9, 14 and 18 % on DM basis) in the concentrate formulated with using different amount of ground corn grain or corn gluten meal. There were significant effects of increasing CP intake on CP digestibility but not on DM digestibility. Despite different CP intake, apparent fecal N outputs were not significantly affected. However, amounts of N excreted into urine increased (p<0.05) with increasing CP intake. There was an obvious effect of live body weight on efficiency of body protein conversion of CP consumed in excess of animal requirement for maintenance, with slopes of 70 % and 46 ~ 39 % for growing and fattening stage, respectively. Nitrogen excretion into feces and urine in this experiment was 70 % of the daily N consumption for fattening stage, compared with 60 % for growing stage. (Key weeds : CP intake, Growth stages, Hanwoo steers, N excretion)

Study on the Management Level of Pathogenic Bacteria in HACCP System Implemented Animal Farms

The aim of this study was to understand the management level of pathogenic bacteria in HACCP system implemented animal farms. Microbial samples were collected from manure, floor, compost depot, manure on belt, low milk tank, dust in laying house and egg collector in HACCP system implemented Korean beef cattle, dairy cattle, swine, and laying Hens farms. O157, O111 and O26 strains of E. coli were not detected in HACCP system implemented Korean beef cattle farm. The detection rate of E. coli from manure and floor in HACCP system implemented cattle farms (Korean beef cattle and dairy farm) was lower than those of non-HACCP system implemented cattle farm. Salmonella spp. was detected in HACCP system implemented cattle farms (Korean beef cattle and dairy farm). Compared with pervious studies, lower detection rate of Salmonella spp. at floor and compost depot in HACCP system implemented swine and commercial layer farms were indicated. In conclusion, implementation of HACCP system in animal farms would enhance the management level of biological hazard compare to normal animal farms.

Effects of Thymol, Eugenol and Malate on In vitro Rumen Microbial Fermentation

The purpose of this study was to investigate effects of increased levels of eugenol, thymol and malate on pH and the concentrations of VFA, lactate and ammonia-N during in vitro ruminal incubation. One Hanwoo beef steer (741 kg) fitted with a rumen cannula was used and fed 0.5 kg/day rice straw and 10 kg/day corn-based concentrate (ratio of concentrate to rice straw = 95 : 5 on DM basis). Three different doses of thymol, eugenol and malate were used. Treatments of the experiment were as follows: Treatments of thymol were control (1g D-glucose/40ml), T1 (1g D-glucose + 40 mg thymol/40 ml), T2 (1g D-glucose + 50 mg thymol/40 ml) and T3 (1g D-glucose + 60 mg thymol/40 ml). Treatments of eugenol were control (1g D-glucose/40 ml), E1 (1g D-glucose + 55 mg eugenol/40 ml), E2 (1g D-glucose + 65 mg eugenol/40 ml) and E3 (1g D-glucose + 75 mg eugenol/40 ml). Treatments of malate were control (1g D-glucose/40ml), M1 (1g D-glucose + 25 mg malate/40ml), M2 (1g D-glucose + 50 mg malate/40 ml) and M3 (1g D-glucose + 100 mg malate/40 ml). The results of this study showed that eugenol and thymol have improved stability of the ruminal fermentation by decreasing lactic acid concentration and increasing ruminal pH. However, it inhibited the production of total VFA, acetate and propionate. Malate also improved stability of the ruminal fermentation by decreasing lactic acid concentration and increasing ruminal pH, but it had a very little effect on ruminal lactate concentrations and pH. On the other hand, malate did not decrease the concentrations of total VFA, acetate and propionate. Therefore, at the low ruminal pH expected in high-concentrate diets, thymol, eugenol, and malate are potentially useful in Hanwoo finishing diets. Further studies are necessary for determining the effectiveness of these additives on in vivo rumen fermentation and animal performance in Hanwoo finishing steers.

Energy Balance and Methane Production of Hanwoo Cows Fed Various Kind of Roughage

This experiment was conducted to determine methane production and emission factors for a range of roughage diets fed to Hanwoo cows at a level of maintenance energy requirement. Seven cows were fed mixed hay only, 12 cows were fed mixed hay containing 30~50% rice straw and 6 cows were fed a mixed hay diet supplemented with 1.0 kg of wheat bran. Each cow was placed in a metabolic crate for 10 consecutive days, including last 7 days for sampling of feces and urine. At the end of the sampling period, the cows were transferred to an open-circuit respiration chamber for 24 consecutive hours. Methane conversion rate (5.5~6.2%, mean value = 5.8%) and emission factor (33.6~38.6 kg/head/year, mean value = 35.2) were not significantly affected by the diets although the mixed hay only diet resulted in 11 and 15% higher respective rates than the other two. However, in light of the many assumptions that forage with good quality might reduce methane production, additional experiments should be required for participation in the greenhouse gas emission trading system. (Key words : Hanwoo cow, Maintenance, Methane emission factor, Roughage sources)

Effects of Caprylic Acid and Cyclodextrin Complex on In vitro Fermentation Characteristics and Methane Production

This study was conducted to evaluate the effects of dietary addition of caprylic acid(CA)-cyclodextrin (CD) complex on in vitro fermentation characteristics, total gas and methane production. Experiment was done with six treatment groups; 1) no CA-CD complex(control), 2) CA 20 mg(T1), 3) CD 830 mg(T2), 4) CA-CD complex 425 mg(T3), CA-CD complex 850mg(T4), CA-CD complex 1,700 mg(T5). Ruminal pH, ammonia and total VFA concentrations of T2, T3, T4 and T5 were lower(P

In vivo evidence on the functional variation within fatty acid synthase gene associated with lipid metabolism in bovine longissimus dorsi muscle tissue

In Korean cattle, intramuscular fat (IMF), or marbling, of the longissimus dorsi muscle (LM) cross section is one of the most important indicators of beef quality and are influenced by environmental and genetic factors. This study was to evaluate the effect of SNPs on the beef quality in Korean cattle for functional studies, such as site-directed mutagenesis based on bovine adipocytes. The fatty acid synthase (FASN) gene plays an important role in lipogenesis. FASN is an essential metabolic and multifunctional enzyme in fatty acid synthesis. Several studies have reported that SNPs g.841G, g.16024A, g.16039T, and g.17924G have a significant impact on marbling scores in Korean cattle and Japanese Black cattle population. These SNPs are located in transcription factor binding sites, the beta-ketoacyl reductase, and thioesterase domains. Our results revealed that the g.17924 A>G SNP is located in the thioesterase domain of the FASN protein, and changes from polar, neutral, and hydrophilic to nonpolar, aliphatic, and hydrophobic, respectively. In in vivo LM tissue of Korean cattle, the g.17924A>G SNP has an effect on increasing fat deposition. Therefore, g.17924A>G SNP could be a causal mutation for increasing fat deposition in Korean cattle LM tissue.

Effect of Types of Milking Instrument and Season on Milk Composition in Holstein-Friesian lactating Cows

ABSTRACT This study was conducted to examine the effect of different types of milking instrument and season on milk composition (fat, protein, non-fat milk solids, milk urea nitrogen and somatic cell count) on Holstein-Friesian lactating cows. Raw milk samples were collected from 20 automatic milking system (AMS) installed dairy farms and 85 conventional milking system (CMS) installed dairy farms. Milk fat, protein, NFMS and MUN contents did not changed between AMS and CMS and different seasons. On the other hand, the average SCC in AMS was 239×10 3 cells/mL which was lower than in CMS (373×10 3 cells/mL, (p<0.05). In conclusion, present results indicated that SCC in milk might be influenced by AMS. However, this area needed more study to confirm the reason of reducing SCC content from AMS. ( Key words : Automatic milking system, Conventional milking system, Season, Milk compositions) 서 론 1980년대 이후 젖소 사육농가 수는 지속적인 하락세를 보이고 있는 반면에 농가당 사육 두수는 1984년 9두에서 2013년 현재 71두로 지속적으로 증가해 왔다(Statistics Korea, 2013). 이는 국내 젖소농장도 타 축종과 유사하게 복합경영 농가 형태에서 전업농 또는 기업농 형태의 단일경영으로 빠르게 변화하고 있는 것으로 판단된다. 이에따라 목장의 착유시스템에도 많은 발전이 있었는데, 가구당 착유우 두수가 10두 미만인 1980년대에는 주로 손으로 착유를 하였으며 1980년대 중반 이후, 콤프레셔와 버킷식 설비가 목장에 도입되었으며, 냉각기 보조금 지급 및 보냉기능이 있는 집유차량이 목장별로 운행하기 시

Determination of Crude Protein Requirements for Maintenance of Prepubertal Hanwoo Heifers

Two trials at different body weights of Hanwoo heifers (average body weight of 143 and 257 kg, respectively) were conducted to determine crude protein requirements for maintenance (CPm). Six Hanwoo heifers in each trial were used in two 3 3 Latin square design with three diets containing three levels of CP, 14 days in each period. In trial 1, the diets were based on 2.8 kg fresh wt./day/heifer timothy hay (LCP) with supplements of either 250 g ground corn and 150 g corn gluten meal (MCP) or 500 g ground corn and 300 g corn gluten meal (HCP). In trial 2, the diets were based on 4.8 kg fresh wt./day/heifer timothy hay (LCP) with supplements of either 350 g ground corn and 250 g corn gluten meal (MCP) or 700 g ground corn and 500 g corn gluten meal (HCP). In trial 1, CP intakes were 236.6, 340.1, and 459.8 g/d for LCP, MCP, and HCP, respectively. Crude protein balances were 0.51, 1.87 and 3.20g//d for LCP, MCP, and HCP, respectively. In trial 2, CP intakes were 415.2, 606.9 and 793.0g/d for LCP, MCP and HCP, respectively. Crude protein balances were 0.67, 1.03, 2.99 g//d for LCP, MCP, and HCP, respectively. The maintenance requirements for CP from the regression equation between CP intake and CP balance were 4.58g//d (trial 1) and 5.02 g//d (trial 2) and lower than the value (5.56 g//d) adopted by Korean Feeding Standards for Hanwoo (2007).