• Korean Journal of Environment and Ecology
• /
• v.31 no.1
• /
• pp.30-41
• /
• 2017

Mammals in Korea have been studied in various fields such as animal science, veterinary medicine, laboratory animal science, ecology, and genetics. As the importance of biodiversity has been emphasized recently, conservation and management of mammals have attracted much public attention. However, in spite of such an increase in scientific research and public interest, it is still difficult to find a report or summary to grasp the trend of mammalian research in Korea. The purpose of this study is to provide the basic data for future plans of the detailed research area and the related policies by grasping the research trends of mammals in Korea. Using text-ming and co-word analysis, we analyzed 392 mammalian research papers published in Korean national journals as of 2015. Our results showed that the number of mammalian research papers published in Korea has gradually increased and that the research target species have also become increasingly diverse. The major research areas identified through text-mining and co-word analysis are (1) evolution/phylogenetics/genetics, (2) environmental science/ecology, (3) embryology/reproductive biology/cell biology, (4) veterinary medicine related to parasites, (5) parasitology related to rodents, (6) bacteriology/virology, (7) anatomy/cell biology/laboratory animal science, (8) veterinary science related to morphology and anatomy, (9) animal science, (10) marine mammalogy, and (11) Chiroptera (bat) research. Environmental science/ecology has been the most active field among the 11 research areas in recent times, and the proportion of research has increased sharply compared to the past. Environmental science/ecology is the core of biodiversity conservation, and as the importance of biodiversity has been emphasized in recent years, researchers' interest in mammal ecology appears to have increased. We expect that the results of this study will be useful for future research plan and related policies on mammals in Korea.

• The Korean Journal of Zoology
• /
• v.36 no.3
• /
• pp.408-415
• /
• 1993

Studies on seasonal prevalence and geographical distribution of chigger mites were carried out during the period of August 1990-December 1991, and the results are summarized as follows. From total 325 field rodents collected during the study period, 15,679 chiggers were obtained and 12 species of 4 genera were identified. Leptotrombidium pallidum, a vector species of tsutsugamushi disease in Korea was the predominant species and distributed throughout the country except southern part of Korea, whereas L. scutellare, known also as a vector species was distributed mainly in southern part of Korea. The distribution of chigger mites was strongly localized by species, showing different predominant species at each locality during the same season. The predominant species were L. pallidum(92.3%) at Dorai-5ri, Wondang-ub, Neotrombicula kwangneungensis (44.7%) at Sanjung-ri, Pochun-gun, N. tamiyai (55.1%) at Changgok-ri, Paju-gun, L. orientale (55.2%) at Jangsin-ri, Iksan-gun, and L. scutellare (47.6%) at Sinyong-dong, Iri-si. Study on seasonal prevalence of L. pallidum chiggers resulted that they started appearing in September, showed the peak in November, almost disappeared during the period of December-March, reappeared in April-May showing a small peak, and again almost disappeared until September. L. scutellare showed the peak in October, sharply decreased thereafter, and disappeared during the period of January-September.

• Asian-Australasian Journal of Animal Sciences
• /
• v.32 no.4
• /
• pp.592-598
• /
• 2019

Objective: Autophagy is a bulk degradation system for intracellular proteins which contributes to skeletal muscle homeostasis, according to previous studies in humans and rodents. However, there is a lack of information on the physiological role of autophagy in the skeletal muscle of meat animals. This study was planned as a pilot study to investigate changes in expression of two major autophagy-related genes, microtubule-associated protein 1 light chain $3{\beta}$ (MAP1LC3B) and autophagy related 7 (ATG7) in fattening beef cattle, and to compare them with skeletal muscle growth. Methods: Six castrated Japanese Black cattle (initial body weight: $503{\pm}20kg$) were enrolled in this study and fattened for 7 months. Three skeletal muscles, M. longissimus, M. gluteus medius, and M. semimembranosus, were collected by needle biopsy three times during the observation period, and mRNA levels of MAP1LC3B and ATG7 were determined by quantitative reverse-transcription polymerase chain reaction. The expression levels of genes associated with the ubiquitin-proteasome system, another proteolytic mechanism, were also analyzed for comparison with autophagy-related genes. In addition, ultrasonic scanning was repeatedly performed to measure M. longissimus area as an index of muscle growth. Results: Our results showed that both MAP1LC3B and ATG7 expression increased over the observation period in all three skeletal muscles. Interestingly, the increase in expression of these two genes in M. longissimus was highly correlated with ultrasonic M. longissimus area and body weight. On the other hand, the expression of genes associated with the ubiquitin-proteasome system was unchanged during the same period. Conclusion: These findings suggest that autophagy plays an important role in the growth of skeletal muscle of fattening beef cattle and imply that autophagic activity affects meat productivity.