Protected area co-management and land use conflicts adjacent to Phu Kao – Phu Phan Kham National Park,Thailand

This study examined land use conflicts between three villages and Phu Kao – Phu Phan Kham National Park in northeast Thailand that resulted from its access and utilization during 2013–2015. The source of conflict is usufruct rights, a government entitlement program designed to honor villagers who lived on the land before it was established as a national park or forest reserve. Ironically, designation of protected areas is not a safeguard for biodiversity. A complex set of rules and regulations control access to resources, but compliance is subject to government oversight and economic pressure to improve quality of life. Granting usufruct rights may reduce certain land use conflicts, but they fail to address agricultural expansion inside park and forest boundaries. For example, agricultural encroachment in this protected area increased by 13.1% during the study period, mainly through cassava plantings. Cassava requires a small amount of maintenance and has a high market value since it is being promoted as an energy crop by the Thai government. A variety of management strategies are needed for sustainable forestry, such as regular forest patrols, reduction of agricultural-based income, and community-based initiatives.     

利用内部信息的农用自动引导行走车的研究(第2报)——MAP(Map And Planning)系统

介绍农用自动引导行走车研究的地图和路径计划系统(MAP系统)。针对农业领域作业的实际情况,建立了农田的环境模型和环境地图,并采用图论的方法开发了路径计划系统,进而构造了路径地图。     

Efficacy of thiabendazole, mebendazole, levamisole and ivermectin against gullet worm, Gongylonema pulchrum: in vitro and in vivo studies

In vitro and in vivo studies were conducted to evaluate the effects of thiabendazole, mebendazole, levamisole and ivermectin against Gongylonema pulchrum. For in vitro assays, third-stage larvae (L3) incubated with the drugs were administered orally to mice and the ability of larvae to invade the gastric mucosa of the animals was examined. After incubation, only those larvae treated with high concentrations of levamisole (1 and 10 microg/ml) were tightly coiled with intestines exhibiting morphological abnormalities. Good dose-response data for the drugs tested was observed at the time of worm recovery from mice, with no worms recovered at the two highest concentrations of levamisole. In vivo efficacy of the drugs against adult worms was evaluated in six groups of three rabbits, each of which was infected with 30 L3 of G. pulchrum and treated with thiabendazole at 100 mg/kg for 3 days, mebendazole at 70 mg/kg for 3 days, levamisole as a single dose of 8 mg/kg, and subcutaneously injected ivermectin as a single dose of 0.2 mg/kg or vehicles of the drugs (control) at 4 months post-infection. Necropsy 14 days after treatment revealed that levamisole, mebendazole and ivermectin reduced worm burdens by 63.2%, 22.8% and 25.8%, respectively, with no reductions in worms observed with thiabendazole. The surviving worms were principally found in the esophagus with the remainder distributed among the buccal mucosa, the tongue, and/or pharyngeal mucosa in all groups. A number of morphologically abnormal eggs were observed within the uterus and ovijector in female worms recovered from the thiabendazole-treated group. These findings suggest that levamisole exhibits in vivo efficacy against G. pulchrum infection and that the larval invasion tests using mice could be used to screen for anthelmintic susceptibility of nematodes.     

Etiologic study of upper respiratory infections of household dogs

Infectious tracheobronchitis (ITB), also known as the kennel cough, is a respiratory syndrome of dogs and usually appears to be contagious among dogs housed in groups. Etiologic agent of ITB is multiple and sometimes complex. In the present study, 68 household dogs showing clinical signs of respiratory infection were examined, and 20 dogs (29.4%) were found to be positive for either of following agents. Bordetella bronchiseptica (B.b.) was most frequently detected from nasal and oropharynx sites of 7 dogs (10.3%). Among the viruses examined, canine parainfluenza virus (CPIV) was detected with the highest frequency (7.4%). Other pathogens included in the order of frequency group 1 canine coronavirus (4.4%), canine adenovirus type 2 (2.9%), group 2 canine respiratory coronavirus (1.5%), and canine distemper virus (1.5%). Only 2 cases showed mixed infections. Neither influenza A virus nor canine bocavirus (minute virus of canines) was found in any dogs examined. These results indicate that both B.b. and CPIV are likely to be the principal etiologic agents of canine ITB in Japan, and they may be considered as the target for prophylaxis by vaccination.     

Substitute and complement relations among various fish species in the Japanese market: implications for fishery resource management

A demand system analysis was conducted to examine the substitute relationships between tuna and skipjack tuna in the Japanese market. Data from the Annual Report on Family Income and Expenditure Survey from 1965 to 2006 were used for the analysis using the almost ideal demand system (AIDS). Results suggest that skipjack tuna can be a strong substitute for tuna, while other fish groups are not a clear substitute. Our analysis of substitute relationships among fish species in a market indicates that this is a factor that should be considered for better fisheries resource management. For instance, even under a situation where one fish species is underexploited, proper attention to its fishery management is necessary if the fish is a strong substitute for another popular fish species in the market.     

Germination and appressorium formation of Pyricularia oryzae Cavara can be inhibited by reduced concentration of Blasin®Flowable with carbon dioxide microbubbles

We investigated the possibility to reduce the usage of Blasin^®Flowable (BF), a disinfectant inhibiting the germination and appressorium formation of Pyricularia oryzae Cavara conidia, by using carbon dioxide microbubbles (CO₂MB). Germination was significantly inhibited by 10 000-fold diluted BF solution containing CO₂MB generated by the decompression-type generator compared to CO₂ millibubbles (CO₂MMB) and CO₂MB generated by the gas-water circulating-type generator. Appressorium formation in the 10 000-fold diluted BF solution containing both CO₂MBs was less than that in CO₂MMB. Scanning electron microscopy showed wrinkles and dents on the surface of conidia treated with 5 000-fold diluted BF solution containing both CO₂MBs. Via transmission electron microscopy, we observed the expansion of the vacuole and the intracellular space and bloated or absent lipid granules in the conidia treated with BF solution containing both CO₂MBs. Our results show that inhibition of the conidium germination and appressorium formation of P. oryzae Cavara by 10 000-fold diluted BF solution could be achieved by using the decompression-type CO₂MB.