‘Luckyone 2ho’ is a new orchardgrass (Dactylis glomerata L.) cultivar developed by the National Institue of Animal Science (NIAS) in 2017. To develope the new variety of orchardgrass, 5 superior clones were selected and polycrossed for seed production. The agronomic growth characteristics and forage productivity of ‘Luckyone 2ho’ were examined at Cheonan from 2012 to 2014, and regional trials were conducted in Cheonan, Pheonchang, Jinju and Jeju from 2015 to 2017, respectively. ‘Luckyone 2ho’ showed medium type growth habit in fall, and medium in length of flag leaf and very long upper internode. Plant height of ‘Luckyone 2ho’ was 3 cm less than that of standard cultivar, ‘Potomac’ and heading date was 1 days later than 5th May compared to standard cultivar, ‘Potomac’. Characteristics such as waterlogging and disease resistance of ‘Luckyone 2ho’ were stronger or better than those of standard cultivar, ‘Potomac’, Especially, dry matter yield of ‘Luckyone 2ho’(15,980 kg/ha) increased 9 % compared to that of standard cultivar, ‘Potomac’(14,702 kg/ha). Nutritive values were appeared to be similar in both varieties except in Vitro dry matter digestibility(IVDMD) and crude protein and total digestible nutrients (TDN).

This study was conducted to evaluate feed value of imported hays and examine current situation of species and hay grade. To evaluate the quality of the imported hay, 133 pieces including 9 species of roughage types were collected at the national hay importers, the TMR companies and livestock farms from 2016 to 2018. The quality grades of imported hay were 3~4 and most imported hay were considered to had low. The ADF, Ash, TDN and DDM in feed composition of alfalfa by quality grades presented significant differences(p<0.05). The quality grade on alfalfa was not similar to the actual quality grades calculated through feed composition. The feed composition of grasses by quality degrees presented significant differences in all contents except DM and CP (p<0.05). As the distributed grasses of the unmarked quality grade was low quality and accounted for 49%, it is urgent to present quality standards based on feed composition. As these results, the grades of imported hays were lower than the marked quality grades. Therefore, the imported roughage’s(hay) price that considered to only quality grades on the marked imported roughages(hay) package can cause a loss to the livestock farms as economic damage. An institutional arrangement should be established to review the quality grades of imported hay.

This experiment was carried out to study the effects of different environmental conditions and cultivation techniques on productivity of forage corn in central and southern area of Korea on 2017 and 2018. Average dry matter yield of forage corn at 34 cultivation regions was 13,510kg/ha. Forage productivity of forage corn cultivated at actual production sites have positive correlation with cultivation techniques(p<0.01) but not correlated with cultivation environments. Forage productivity of forage corn have positive correlation with seeding techniques(p<0.01) but not correlated with fertilization techniques. These results suggest that practices of cultivation techniques are more important than cultivation environments for increasing the forage productivity of forage corn. Therefore, yield prediction techniques of forage corn in Korea have to be considered the practices of cultivation techniques along with soil and climate conditions.

In the summer season, natural ventilation is commonly used to reduce the inside air temperature of greenhouse when it rises above the optimal level. The greenhouse shape, vent design, and position play a critical role in the effectiveness of natural ventilation. In this study, computational fluid dynamics (CFD) was employed to investigate the effect of different roof vent designs along with side vents on the buoyancy-driven natural ventilation. The boussinesq hypothesis was used to simulate the buoyancy effect to the whole computational domain. RNG K-epsilon turbulence model was utilized, and a discrete originates (DO) radiation model was used with solar ray tracing to simulate the effect of solar radiation. The CFD model was validated using the experimentally obtained greenhouse internal temperature, and the experimental and computed results agreed well. Furthermore, this model was adopted to compare the internal greenhouse air temperature and ventilation rate for seven different roof vent designs. The results revealed that the inside-to-outside air temperature differences of the greenhouse varied from 3.2 to 9.6oC depending on the different studied roof vent types. Moreover, the ventilation rate was within the range from 0.33 to 0.49 min-1. Our findings show that the conical type roof ventilation has minimum inside-to-outside air temperature difference of 3.2oC and a maximum ventilation rate of 0.49 min-1.

This study was carried out to explore the accuracy of near infrared spectroscopy(NIRS) for the prediction of moisture content and chemical parameters on winter annual forage crops. A population of 2454 winter annual forages representing a wide range in chemical parameters was used in this study. Samples of forage were scanned at 1nm intervals over the wavelength range 680-2500nm and the optical data was recorded as log 1/Reflectance(log 1/R), which scanned in intact fresh condition. The spectral data were regressed against a range of chemical parameters using partial least squares(PLS) multivariate analysis in conjunction with spectral math treatments to reduced the effect of extraneous noise. The optimum calibrations were selected based on the highest coefficients of determination in cross validation(R2) and the lowest standard error of cross-validation(SECV). The results of this study showed that NIRS calibration model to predict the moisture contents and chemical parameters had very high degree of accuracy except for barely. The R2 and SECV for integrated winter annual forages calibration were 0.99(SECV 1.59%) for moisture, 0.89(SECV 1.15%) for acid detergent fiber, 0.86(SECV 1.43%) for neutral detergent fiber, 0.93(SECV 0.61%) for crude protein, 0.90(SECV 0.45%) for crude ash, and 0.82(SECV 3.76%) for relative feed value on a dry matter(%), respectively. Results of this experiment showed the possibility of NIRS method to predict the moisture and chemical composition of winter annual forage for routine analysis method to evaluate the feed value.

South Korea has over 0.38 million of managed honey bee (Apis cerana) colonies before 2009 years ago, which produce the highest quantity of honey in the Korea; however, almost colony (90%) were collapsed by Korean Sacbrood Virus (KSBV) in South Korea. Korean Sacbrood Virus (KSBV) is the pathogen of A. cerana Sacbrood disease, which poses a serious threat to honeybee A. cerana, and tends to cause bee colony and even the whole apiary collapse. Colony collapse of A. cerana was first reported on the Pyeong-Chang of the South Korea in 2009. Several scientists and governments has been tried research for cure the sacbrood disease in A. cerana colony by medicines and management techniques. Unfortunately, The sacbrood disease dosen’t improve. So, we were developed a better breed of A. cerana for resistance of sacbrood virus by selection and then artificial insemination. A. cerana breeding technique was first successful applied with A. cerana in Korean. Queens was grafted from sacbrood resistance line and then it was growing in sacbrood disease colony that was survived 100%. Altogether selected 18 queens were artificially inseminated and 2,000 drones of A. cerana in Korea was used to evaluate amount of semen collection. We are select two scabrood resistance A. cerana line (R and H). R line be used for rearing the Queen. Drone was reared in H line colony. The RH hybrid were not infected sacbrood virus even spread sacbrood virus (2×106). RH colonies have very excellent hygienic behavior, brood, and sacbrood disease resistance activity.

Excessive intake of red meat has been associated with colon carcinogenesis. The effect of hemin and zinc on colon carcinogenesis was investigated in male ICR mice. After acclimation for 1 week, five-week-old mice received three s.c. injections (0-2nd weeks of the experiment) of azoxymethane (AOM; 10 mg/kg b.w.) weekly and were treated by 2% dextran sodium sulfate (DSS) in drinking water for the next 1 week to induce aberrant crypt foci (ACF). Mice were fed on AIN-76A purified rodent diet for 6 weeks. There were three experimental groups; control, hemin, and hemin + zinc groups. The daily oral doses of hemin and zinc were 534 mg/kg and 55 mg/kg b.w., respectively. After staining colonic mucosa with 0.2% methylene blue, the ACF, aberrant crypts (AC), and polyps were counted. Lipid peroxidation in liver was evaluated by thiobarbituric acid-reactive substances (TBARS) assay. The numbers of AC, ACF, large ACF (i.e., ≥4 AC/ACF), and polyps in the hemin group were higher than those in the control group. In hemin + zinc group, the numbers of AC, ACF, large ACF were significantly lower compared to the hemin or control groups (p < 0.05), and the number of polyps was also significantly lower compared to that in the hemin group (p < 0.05). The TBARS level in the livers of the hemin + zinc group was significantly lower than that of the hemin group (p < 0.05). These results suggest that hemin enhances colon carcinogenesis and that co-treatment with zinc can protect against the induction of colon carcinogenesis.

본 연구는 이탈리안 라이그라스 재배현장에서 재배환경과 재배기술의 차이에 따른 조사료 생산성의 변화 요인을 분석 하기 위하여 2016부터 2017년까지 수행되었다. 우리나라 중부 및 남부지역에서 27개 이탈리안 라이그라스 재배지의 평균 건물수량은 6,940kg/ha이였다. 이탈리안 라이그라스 재배현장의 생산성은 재배환경보다 재배기술과 높은 상관(p<0.01)이 있는 것으로 나타났다. 재배기술 중에서 파종기술 및 포장관리기술과 생산성 간에는 고도의 상관이 있었으나, 시비기술과 생산성 간에는 상관이 없었다. 이상의 결과는 이탈리안 라이그라스의 생산성 향상에는 재배환경보다 재배기술의 현장실천이 더 중요함을 제시하고 있다. 따라서 우리나라 지역별 이탈리안 라이그라스의 생산성 예측기술의 정밀도를 높이기 위해서는 그 지역의 기상 및 토양환경은 물론 재배기술의 적용을 충분히 고려하여야 할 것으로 사료된다.