In the winter forage study, Italian ryegrass(IRG) and barley were selected. In 2018, the dry matter yield of IRG was 16,915kg per ha under the Agrivoltaic System; this was a little more than 16,750kg per ha of outdoors. On the contrary, the dry matter yield of barley was slightly less under the Agrivoltaic System than that of outdoors. In 2019, the dry matter yield under the Agrivoltaic System was 12,062kg per ha for IRG and 12,195kg per ha for the barley; this was 5.4% and 11.5% less than that of outdoors, respectively. In the summer forage study, corn and sorghum×sudangrass were selected. In 2019, the dry matter yield of corn under the Agrivoltaic System was 13,133kg per ha which was 17% less than that of outdoors. The dry matter yield of sorghum×sudangrass was 12,450kg per ha, which was 82.5% of that of outdoors. In 2020, the dry matter yield of corn under the Agrivoltaic System was 8,033kg per ha which was 7.9% less than that of outdoors. The dry matter yield of sorghum×sudangrass was 5,651kg per ha, which was 11.4% less than that of outdoors.

This study was conducted to establish spring sowing techniques in preparation for the impacts of climate change on sowing time and wintering rates of winter forage crops such as barley, oat and IRG. Oat showed the highest yield in 2017 which had relatively dry climate condition. And when sowing in late Febrnary 2017 yielding 9,408kg/ha were obtained, yielding 4,011kg/ha more than IRG's sown in the same period. In 2018 which had relatively wet climate condition, four barley species decreased in the production from the previous year. Oat also had decreased by 70% from 9,408kg/ha to 2,851kg/ha. On the other hand, IRG maintained the production in the mid-5,000kg/ha range. It was also found that IRG had the least variability due to external influences regardless of seeding period for 2 years. Mixed sowing with IRG and oat in 50:50 ratio was the highest dry matter, 6,584kg/ha, and IRG was 18.5% and Oat was 2.3 times higher than single planting.

This study was conducted in 2014 in the Gangjin area of Jeonnam province for the purpose of confirming the potential of Kenaf as an alternative feed crop of rice. The weather and soil conditions were favorable and there was no adverse effect on the growth of Kenaf. The amount of seeding was given at 10 kg, 15 kg and 20 kg. As the seeding volume increased, plant height and dry matter yield increased, and stem diameter and number of nodes decreased. The highest growth rate was observed between 75 and 90 days from the date of planting(p<0.05). As the growth progressed, stem rate increased and leaf rate decreased(p<0.05). Increased amount of seeding and growth resulted in decreased CP and TDN and increased ADF and NDF, which resulted in the decreased economic value of Kenaf as a feed crop. The result of increasing the use of organic fertilizer to 20 kg and 30 kg was similar to increasing the amount of seeding. As organic fertilizer usage increased, dry matter yield and growth rate improved(p<0.05).

This study investigated the stress-related metabolites and hormones in blood and compared the muscle structure to identify the reason for blood splash in Hanwoo beef. Five slaughter houses were selected based on the region (Seoul, Gimhae, Jungbu, Naju, and Goryung) and a previous blood splash record. In total, three-hundred eighty blood samples (n=380) and forty-two muscle tissues (n=42) of control and blood splash Hanwoo beef were collected during the slaughter process and beef grading. Blood metabolites were analyzed including glucose, lactate, creatinine, urea-N, and hormones such as cortisol and thyroxin. Muscle fiber, fiber bundle, and capillary wall thickness were measured under microscope. The concentrations of blood glucose, lactate, and urea-N were not significantly different between the control and the blood splash samples. Cortisol and thyroxin levels were not significantly different in both samples. In contrast, the creatinine level was significantly increased (p<0.05) in the blood splash samples. There were also no significant differences observed in muscle fiber, bundles, and capillary wall thickness between the control and the blood splash tissues. In conclusion, blood metabolites, hormones, and muscle fiber showed no differences between the control and the blood splash animal. However, increased creatinine levels may be used as an indicator for identifying blood splash prior to slaughter in Hanwoo.

This study was conducted to investigate the effect of hormones, protein sources and anti-oxidants on in vitro maturation (IVM) and in vitro fertilization(IVF) of bovine follicular oocytes. The rates of Holstein follicular oocytes classified as grade A and B(50.2% and 33.2%) were higher than those of Hanwoo cattle(40.3% and 32.0%, P<0.05). The cumulus cell expansion rates of oocytes cultured in TCM-199 and Ham's F-10 medium supplemented with 10% FCS and hormones were higher (81.9~87.6%) than those of non-treated groups (74.5~81.7%). The fertilization rates of oocytes cultured in TCM-199 and Ham's F-10 medim supplemented with 10% FCS, 1% BSA and 10% bFF was 53.8~55.0%, 51.4~52.6%, and 47.0~50.0%, respectively. The polyspermy rates was 13.6~14.2%, 10.0~11.1%, and 10.0%, respectively. When the oocytes were cultured in TCM-199 and Ham's F-10 medium with 50 -tocopherol, the fertilization rates was 62.0 and 60.2%, respectively. In the maturation medium added of 100 cysteamine, the fertilization rates was 64.7 and 66.7%, respectively. The fertilization and polyspermy rates of treated groups were higher than those of non-treated group. The results show that hormones, protein sources and anti-oxidants can provide a benefit for in vitro maturation and fertilization of bovine follicular oocytes.

The effect of several potential antioxidants were examined as a means of increasing the in vitro development of in vitro matured and in vitro fertilized oocytes into morulae and blastocysts. Korean native cattle embryos after in vitro fertilization were cultrued for 7 days at 38.5 in CR1aa containing varing concentration of the antioxidants in a gas phases consisting of 5% CO2, 95% humidified air. The results obtained were summarized as follows; The proportion of embryos developed to morulae and blastocysts in CR1aa containing 2.5uM -tocopherol(11.0% and 6.0%) was significantly higher than those of 0, 5.0, and 7.5uM -tocopherol (P<0.05). concentration of 50uM L-ascorbic acid (7.5% blastocysts) did affect the proportion of embryos developing into blastocystes(P>0.05). Addition of 200uM cysteamine was significantly higher than those of 0, 100 and 300uM (P<0.05). When the fertilized oocytes were cultured at 0. 200, 400 and 600uM of selenium for 168 hrs, the morulae rates were 12.2, 5.2, 16.0 and 16.1% respectively, and addition of 200uM selenium was significantly higher than those of 0, 400, 600uM (P<0.05). These results suggested that the addition of -tocopherol, L-ascorbic acid, cysteamine and selenicum can enhanced development to the morulae and blastocysts of in vitro derived fertilized oocytes.