This study evaluated the effect of lactic acid bacteria (LAB, a mixture of Enterococcus faecium and Lactobacillus plantarum) supplementation, the storage temperature, and storage period on the fermentation characteristics and in vitro ruminal digestibility of a total mixed ration (TMR). The TMR was prepared into two groups, namely, CON (control TMR without the LAB) and ML (supplementing a mixture of E. faecium and L. plantarum in the ratio of 1% and 2% (v/w), respectively). Both groups were divided and stored at 4°C or 25°C for 3, 7, and 14 d fermentation periods. Supplementing LAB to the TMR did not affect the chemical composition of TMR except for the lactate and acetate concentration. Storage temperatures affected (p<0.05) the chemical composition of the TMR, including pH, lactate, and acetate contents. The chemical composition of TMR was also affected (p<0.05) by the storage period. During in vitro rumen fermentation study, the ML treatment showed lower (p<0.05) dry matter digestibility at 24 h incubation with a higher pH compared to the CON. There was no difference in the in vitro dry matter digestibility (IVDMD) of TMR between the CON and ML treatment however, at 24 h, ML treatment showed lower (p<0.05) IVDMD with a higher pH compared to the CON. The effects of storage temperature and period on IVDMD were not apparent at 24 h incubation. In an in vivo study using Holstein steers, supplementing LAB to the basal TMR for 60 d did not differ in the final body weight and average daily gain. Likewise, the fecal microbiota did not differ between CON and ML. However, the TMR used for the present study did include a commercial yeast in CON, whereas ML did not; therefore, results were, to some extent, compromised in examining the effect of LAB. In conclusion, storage temperature and period significantly affected the TMR quality, increasing acetate and lactate concentration. However, the actual effects of LAB supplementation were equivocal.

The present study was conducted to examine the effect of soybean silage as a crude protein supplement for corn silage in the diet of Hanwoo steers. The first experiment was conducted to evaluate the effect of replacing corn silage with soybean silage at different levels on rumen fermentation characteristics in vitro. Commercially-purchased corn silage was replaced with 0, 4, 8, or 12% of soybean silage. Half gram of the substrate was added to 50 mL of buffer and rumen fluid from Hanwoo cows, and then incubated at 39°C for 0, 3, 6, 12, 24, and 48 h. At 24 h, the pH of the control (corn silage only) was lower (p<0.05) than that of soybeansupplemented silages, and the pH numerically increased along with increasing proportions of soybean silage. Other rumen parameters, including gas production, ammonia nitrogen, and total volatile fatty acids, were variable. However, they tended to increase with increasing proportions of soybean silage. In the second experiment, 60 Hanwoo steers were allocated to one of three dietary treatments, namely, CON (concentrate with Italian ryegrass), CS (concentrate with corn silage), CS4% (concentrate with corn silage and 4% of soybean silage). Animals were offered experimental diets for 110 days during the growing period and then finished with typified beef diets that were commercially available to evaluate the effect of soybean silage on animal performance and meat quality. With the soybean silage, the weight gain and feed efficiency of the animal were more significant than those of the other treatments during the growing period (p<0.05). However, the dietary treatments had little effect on meat quality except for meat color. In conclusion, corn silage mixed with soybean silage even at a lower level provided a greater ruminal environment and animal performances, particularly with increased carcass weight and feed efficiency during growing period.

In horse management, the alarm system with sensors in the foaling period enables the breeder can appropriately prepare the time of the parturition. It is important to prevent losses by unpredictable parturition because there are several high risks such as dystocia and the death of foals and mares during foaling. However, unlike analysis in the alarm system that detects specific motions has been widely performed, analysis of classification following specific behavior patterns or number needs to be more organized. Thus, the objective of this study is to classify signs of the specific behaviors of the mares for the prediction of pre-foaling behaviors. Five Thoroughbred mares (9-20 yrs) were randomly selected for observation of the prefoaling behaviors. The behaviors were monitored for 90 min that was divided into three different periods as 1) from -90 to -60 min, 2) from -60 to -30 min, 3) from -30 min to the time for the discharge of the amniotic fluid, respectively. The behaviors were divided into two different categories as state and frequent behaviors and each specific behavioral pattern for classification was individually described. In the state behaviors, the number of mares in the standing of the foaling group (3.17 ± 0.18b) at period 3 was significantly higher than the control group (1.67 ± 0.46a). In contrast, the number of the mares in the eating of the foaling group (1.17 ± 0.34b) at period 3 was significantly lower than the control group (3.33 ± 0.46a). In the frequent behaviors, the weaving of the foaling group was significantly higher than the control group, and looking at the belly of the foaling group was significantly lower than the control group. In period 2, defecation, weaving, and lowering the head of the foaling group were significantly higher than the control group, respectively. In period 3, sitting down and standing up, pawing, weaving, and lowering the head in the foaling group were also significantly higher than the control group. In conclusion, the behavior is significantly different in foaling periods, and the prediction of foaling may be feasible by the detection of the pre-foaling behaviors in the mares.

This study was conducted to evaluate the effect of rumen origin lactate-utilizing bacteria (LUB) as one of the potential treatments on subacute ruminal acidosis (SARA) during in vitro challenge compared to buffering agents (NaHCO3, sea minerals, MgO) and direct-fed microorganism (yeast). We hypothesized that rumen LUB (RLUB) could be a potential treatment to treat ruminal acidosis. The supplementation level of other treatments was determined by referring to previous studies in the literature. The 108 CFU/g freeze-dried RLUB isolated from Hanwoo cattle were compared with 0.1% NaHCO3, 0.8% of MgO, 0.5% sea mineral and 0.4% yeast during in vitro SARA challenge. Rumen fluid collected from one cannulated Holstein and one Hanwoo steer fed by maize silage was mixed with 0.5g feed consisted of 0.05g forage and 0.45g concentrate. These mixtures were incubated in triplication for 3, 6, 12 and 24h. After 6h of incubation, along with MgO and sea minerals, RLUB treatment showed higher (p<0.05) ㏗ values than control with no significant differences in total volatile fatty acid concentration. However, in the same period, the propionate concentration and A:P ratio were higher in RLUB than in the other treatment (p<0.05), which might alter the fermentation pattern. On the other hand, the RLUB treatment produced a higher (p<0.05) ammonia-N concentration. Based on these results, we can conclude that RLUB might have the potential to alleviate SARA. Nonetheless, further study on its mechanism in SARA is required, especially with live animals.

This study was conducted to evaluate the effect of lactic acid bacteria (LAB) inoculation to domestically-cultivated Italian ryegrass (IRG) on silage fermentation and in vitro ruminal fermentation. There were six treatments based on the LAB inoculants: 1) no addition of LAB (negative control: NC), additions of 2) commercially-available LAB (positive control: PC), 3) Lactobacillus plantarum (LPL), 4) L. paracasei (LPA), 5) L. acidophilus (LA), and 6) L. pentosus (LPT). All treatments were inoculated at a concentration of 106 CFU/g and ensiled for 3, 7, 21, and 42 days in triplicate and analyzed for nutritive values when ensiling was terminated. Day 42 silage from all treatments were also examined for in vitro ruminal fermentation. After 42 days, LAB-inoculated silages had higher (P<0.05) lactic acid concentration compared to the NC. In terms of nutritive values, the silages treated with LPA, LA, and LPT showed higher (P<0.05) crude protein and lower (P<0.05) neutral detergent fiber and acid detergent fiber content compared to the rest of the treatment. In vitro ruminal dry matter degradability was not affected by LAB addition. However, LAB-treated IRG had shown higher (P<0.05) ammonia-N compared with that of the NC. LPA had shown the highest (P<0.05) volatile fatty acid concentration among the LAB examined. In conclusion, the addition of a single strain of LAB appeared to produce a quality IRG silage compared with the NC and the PC. Among the strains examined, LPA seemed to be superior to the others.

본 연구는 우리나라 일반 농가에서 사육중인 한우 암소 348두의 도체중, 등심단면적, 등지방두께 및 근내지방도에 대하여 EBV(Estimated Breeding Value) 및 GEBV(Genomic Estimated Breeding Value)의 정확도를 비교하였다. EBV 분석은 한우 암소 348두의 혈통정보와 농협경제지주 한우개량사 업소의 당대검정우 및 후대검정우의 혈통정보 및 표현형정보를 이용하여 혈연계수행렬(Numeric Relation Matrix, NRM)을 구축하여 BLUP(Best Linear Unbiased Prediction) 방법으로 분석하였다. GEBV 분석은 표현형정보와 유전체정보가 있는 후대검정우 3,820두를 참조집단으로 이용하여 한우 암소 348두의 SNP 50K 정보와 유전체 혈연 행렬(Genetic Relationship Matrix, GRM)을 구축하여 GBLUP(Genomic Best Linear Unbiased Prediction) 방법으로 분석하였다. 그 결과, 한우 암소 348두 에 대한 EBV 및 GEBV의 정확도 차이는 도체중, 등심단면적, 등지방두께 및 근내지방도에서 GEBV의 정확도가 각각 22.90%, 11.14%, 12.28% 및 8.69% 증가됨을 보였다. 이러한 결과는 유전체 선발 시 육종가 추정의 정확도 증가를 볼 수 있을 것으로 기대되며, 이는 유전체선발을 위한 기초자료로써 활용될 수 있을 것으로 판단된다.

Obesity is a risk factor for various diseases, including cardiovascular disease, diabetes, renal disease, hypertension, cancer, and neural disease. Adipose tissue in animals is important for the mobilization of lipids, milk production, deposition of fat in different depots, and muscle and meat production. Understanding the genetic and physiological causes of metabolic disease is a priority in biomedical genome research. In this study, we examined several variables in mice fed a high-fat diet, including serum composition, body weight, total calorie intake, and differentially expressed genes. Body weight and blood glucose levels were not significantly different between animals fed high-fat and normal diets. However, high-fat diet groups showed reduced calorie and food intakes. Levels of sodium, ionized calcium, glucose, hematocrit, hemoglobin, pH, PCO2, PO2, TCO2+, HCO3+, base excess, and SO2 in the blood were not significantly different between mice fed high-fat and normal diets. Serum potassium concentration, however, was lower in mice a high-fat diet. Differentially expressed genes were also compared between the two groups. The purpose of this study was to discover new genes as a result of annealing control primer (ACP) PCR using 20 random primers. Five down regulated genes were identified and three of others were up-regulated by high-fat diet. Known genes were excluded from this result. In addition, the relationships among candidate genes and high-fat diet should be investigated according to potassium concentration in the blood. In conclusion, mice fed normal and high-fat diets showed no significant difference in body weight, whereas high-fat diet led to changesin blood composition and differential expression of several genes. These findings may provide a better understanding of the mechanisms underlying the association between obesity and metabolic diseases.

This study was conducted to elucidate the genetic relationships among native Korean cattle breeds by analyzing genetic variations and distances. Relationships among Hanwoo, Korean brindle, Korean black, Jeju black, and Holstein cattle were evaluated using 15 microsatellite markers. Korean brindle and Korean black cattle had the closest relationship based on the lowest genetic distance being observed between these breeds. A Neighbor-Net tree created using the Reynolds distances indicated that Korean brindle and black cattle formed a group separate from the Hanwoo population. However, an Fst pairwise test revealed that Hanwoo, Korean brindle, and Korean black cattle differed significantly (P <0.01). Moreover, the results of this study confirmed that Jeju black cattle became a separate established breed in Korea through a path different from that of cattle from inland regions, even though it is considered to be a Korean native breed. Overall, the results of our study indicate that Korean brindle and black cattle are indeed native Korean breeds that maintain an endangered status.

본 연구는 한우의 경제형질 관련 유전적 표지인자(DNA marker) 개발을 목적으로 한우 도체형질과의 기능적 후보유전자로부터 검출된 10개의 유전마커(Single Nucleotide Polymorphism; SNP)에 대해서, 환경효과가 다양하게 포함되어 있는 상용축을 대상으로 마커효과를 검정하였다. 그 결과, 한우 후대 검정우에서 통계적 유의성이 인정되었던 다수의 SNP 좌위중 IP3R1 유전자에서 검출된 DNA 마커만 상용축의 근내지방도와 통계적 유의차를 보였으며, 이는 각 좌위마다의 환경 효과와의 보다 더 통계분석이 요구되는 것이며, 향후 근내지방도와 연관된 다수의 마커와 함께 혼합모델을 통하여 개체의 표현형 예측등에 활용이 가능할 것으로 사료된다.

This study aims to identify DNA marker related to health index which is derived from fatty acid composition of Hanwoo meat. We investigated a genetic association between two SNPs (-867G>C and 878C>T) of SCD gene and health indexes. Two health index values (index of atherogenicity and index of thrombogenicity) were derived from a combination of fatty acid composition. Phenotypic correlation indicated that oleic acid (C18:1) was negatively correlated to index of atherogenicity (-0.84) and index of thrombogenicity (-0.91), respectively. Statistical analysis revealed that 878T>C SNP was significantly associated with IA (index of atherogenicity, p=0.012) and IT (index of thrombogenicity, p=0.006). There was no association between the regulatory SNPs (-867G>C and -877Gdel) and health indexes. Haplotype analysis detected 4 main haplotype (GdelT; 0.004, GdelC; 0.344, CGT; 0.350 and CGC; 0.261) in Hanwoo. The GdelT haplotype was significant on IA and IT. The effect of GdelT haplotype showed increasing IA and IT values, while GdelC haplotype has a decreasing IA and IT value in Hanwoo. In conclusion, the 878C>T SNP in the SCD gene seems to have an effect on this health index and might be implemented into animal breeding program.