著者
大久保 響 吉村 珠美 山内 大樹 星野 仏方
出版者
酪農学園大学
雑誌
酪農学園大学紀要. 自然科学編 (ISSN:21870500)
巻号頁・発行日
vol.47, no.1, pp.25-39, 2022-10

On northern Japanʼs Hokkaido Island, wolves (Canis lupus) have been extinct for 100 years. As a result, the sika deer (Cervus nippon) population has increased in recent years, causing damage to agriculture and to the forestry and fisheries industries and leading to an increase in train and automobile traffic accidents. On the other hand, wolves live in Mongolia where stock-farming is the main livelihood. Yet nomadic livestock herders have coexisted with wolves for centuries. The main reason for this successful coexistence in the Mongolian steppes can be attributed to the nomadsʼ understanding of wolf ecology. This understanding has led to the development of ways for humans and apex predators to interact with one another in this ecosystem. We also discovered that livestock damage caused by wolves in Mongolia is minimal because there is sufficient prey (e.g., red deer) and because the wolves and their prey do not live in proximity to humans. We note there has never been a documented attack by a wolf on a human in Mongolia. Our investigation of the habitat of wolves in Hustai National Park (HNP) in Mongolia gave us a base of information to assess the challenges that might occur if wolves are reintroduced into Hokkaido. Based on our habitat assessment of the island, we were able to estimate the carrying capacity of wolves on Hokkaido. We concluded that Hokkaido Island can successfully support approximately 1300 wolves with a prey base of up to 100,000 sika deer.
著者
髙橋 俊彦 夏井 美聡 岸田 美月 北野 菜奈 井上 誠司 菊 佳男
出版者
酪農学園大学
雑誌
酪農学園大学紀要. 自然科学編 (ISSN:21870500)
巻号頁・発行日
vol.47, no.1, pp.1-6, 2022-10

During the suckling period, calves are prone to physiological anemia. Anemic calves often develop respiratory and digestive problems that lead to poor growth. As a precursor of hemoglobin, aminolevulinic acid has an oxygencarrying function in red blood cells in the body, and is expected to prevent anemia. In this study, we examined the effects of feeding aminolevulinic acid to calves on their growth and analyzed whether it had anemia-preventing effects. Our subject calves were six suckling calves, three of which were orally administered an aminolevulinic acid preparation (5 g/day for 60 days; test group), and three of which received no aminolevulinic acid (controls). At 0, 1, and 3 months of age, body weight, height, daily gain, and blood parameters (red blood cell count, hemoglobin, iron, hematocrit, white blood cell count, total protein, and total cholesterol) were measured, and the number of respiratory and digestive diseases and number of days of treatment were investigated. In the test group, body height was significantly higher at 1 month of age, and daily body mass also tended to be higher at 1-3 months of age. In blood tests, the red blood cell count and hemoglobin were below standard values at birth and at 2 months of age in both the test and control groups. Iron and total cholesterol tended to be higher in the test group at 1 and 3 months of age, while white blood cell count and total protein tended to be higher in the control group. In terms of disease status, the number of days of treatment was small in the test group, and no calves were diagnosed with anemia. These results suggest that aminolevulinic acid may improve the nutritional status of calves and be effective in promoting growth and preventing anemia.
著者
梅田 実里 立木 靖之
出版者
酪農学園大学
雑誌
酪農学園大学紀要. 自然科学編 (ISSN:21870500)
巻号頁・発行日
vol.46, no.2, pp.73-79, 2022-03

In the Kiritappu wetlands of Hmanaka Town, sika deer (Cervus nippon yesoensis) have been observed in kelp drying grounds and caused damage due to dung deposition. Therefore, countermeasures are required, but they cannot be implemented due to a lack of basic information on this species. In this study, we instigated camera traps, spotlight counts, and fixed-point and direct observations to clarify deer behaviors in urban areas or kelp drying grounds. Many deer were observed in urban areas between November and December, and between sunset and sunrise in kelp drying grounds. Similarly, deer numbers were lager in areas where electric fences were absent. Their behaviors in urban areas mainly involved “walking” in kelp drying grounds. Whereas the result “feeding” in the unimproved land. It was hypothesized that deer appearance increased in urban areas during the breeding and winter seasons. Also, deer were commonly seen from around sunset to sunrise, walking or feeding in urban areas. Electric fences are often effective measures against deer entry, but cannot completely block or prevent deer access as roads border these fences. In future research, it is important to investigate sika deer intrusion routes and patterns in areas where electric fences are breached.