Kyu-Hyun Park

Co-composting of swine mortalities with swine manure and sawdust

Abstract The treatment of livestock fatalities caused by epidemic diseases must be timely. Simultaneously, the contaminated excreta and bedding materials must also be treated on site without removal. The composting of manure with bulking materials is widely used on the farm, and the temperature during the composting reaches over 60°C under appropriate conditions of moisture and oxygen, with a suitable carbon to nitrogen ratio. These characteristics of composting can be applied to the degradation of dead livestock. Hence, this study was conducted to evaluate the degradability of mortalities during composting with bulking material comprised of swine manure and sawdust. The laboratory and field studies were conducted using mimic swine mortalities (MSM) and real swine mortalities, respectively. The sawdust to swine manure ratios of 20:80, 40:60, 70:30, and 100:0 were treatments identified as T1, T2, T3, and T4. In the laboratory study, high degradation of the mortalities (>85%) occurred in all treatments, except the T1 treatment. The T2 treatment obtained high degradation at a desirable level. In the field study, the degradation of the soft tissues of the mortalities in the T2 and T1 treatments reached 99.7 and 84.5%, respectively. The final C/N ratio of treatment T2 (17.5) was higher than treatment T1 (16.8). The addition of swine manure helped to develop relatively rapid temperature homogeneity between the mortality and the bulking materials, and the sawdust to swine manure ratio of 40:60 proved best for swine carcass degradation.

Comparative genomic analysis of mitochondrial protein-coding genes in Veneroida clams: Analysis of superfamily-specific genomic and evolutionary features

Veneroida is the largest order of bivalves, and these clams are commercially important in Asian countries. Although numerous studies have focused on the genomic characters of individual species or genera in Veneroida, superfamily-specific genomic characters have not been determined. In this study, we performed a comparative genomic analysis of 12 mitochondrial protein coding genes (PCGs) from 25 clams in six Veneroida superfamilies to determine genomic and evolutionary features of each superfamily. Length and distribution of nucleotides encoding the PCGs were too variable to define superfamily-specific genomic characters. Phylogenetic analysis revealed that PCGs are suitable for classification of species in three superfamilies: Cardioidea, Mactroidea, and Veneroidea. However, one species classified in Tellinoidea, Sinonovacula constricta, was evolutionarily closer to Solenoidea clams than Tellinoidea clams. dN/dS analysis showed that positively selected sites in NADH dehydrogenase subunit, nd4 and subunit of ATP synthase, atp6 were present in Mactroidea. Differences in selected sites in the nd4 and atp6 could be caused by superfamily-level differences in sodium transport or ATP synthesis functions, respectively. These differences in selected sites in NADH may have conferred these animals, which have low motility and do not generally move, with increased flexibility to maintain homeostasis in the face of osmotic pressure. Our study provides insight into evolutionary traits as well as facilitates identification of veneroids.

Changes of Microbial Diversity During Swine Manure Treatment Process

We investigated microbial diversity in a manure storage tank (MST) storing untreated manure and an aeration tank (AT) during swine manure treatment process using the next-generation sequencing in order to find the aeration effect on microbial diversity. Proteobacteria were more abundant in the AT group than in the MST group and may include denitrifying bacteria contributing to nitrous oxide (N2O) emission or aerobic bacteria stimulated by oxygen. The opposite held true for the phyla Bacteroidetes and Firmicutes that may include anaerobic bacteria inhibited under aerobic conditions in the AT group.

Complete genome sequence and SNPs of Raja pulchra (Rajiformes, Rajidae) mitochondria

Abstract Mitochondrial genomes were sequenced from five Raja pulchra individuals, and single-nucleotide polymorphisms (SNPs) were identified by comparing previously announced sequences in this study. Total 117 SNPs were detected and they were present in 2 rRNA genes, 9 tRNA genes, 13 protein coding genes and non-coding region. One deleted polymorphic site, which was located in 16S rRNA gene, was observed in two individuals. Six polymorphic sites were non-synonymous SNPs, which were distributed in ND1, ND2, ATP6 and ND4 gene. Phylogenic analysis validated current taxa. The genome sequences of R. pulchra mitochondria could be comparable information for understanding species divergence and genomic variation among the populations.

Life Cycle Assessment of Dairy Cow in Korea

Recently environmental impact caused by livestock receives increasing attention. The objective of this study is to estimate the environmental impact of dairy cow in Korea by life cycle assessment (LCA). System boundary is cradle-to-gate from feedstuff production to farm gate. Functional unit is producing 9,000kg of milk and referece flow is one dairy cow. Environmental impact categories considered include global warming, acidification, ozone layer depletion, abiotic resource depletion, photochemicaloxidant creation, eutrophication, eco-toxicity and human toxicity. Four impact categories were identified significant. They are acidification, eco-toxicity, eutrophication and global warming. Manure management affect significantly on acidification, eco-toxicity and eutrophication, while enteric fermentation dominated by CH4 emission affect global warming.