Effects of salinity and temperature on the larval development of a sesarmid crab Neosarmatium trispinosum Davie (Crustacea: Brachyura: Sesarmidae) from mangrove swamp in Okinawa Island, Japan

The larval development of the semiterrestrial sesarmid mangrove crab Neosarmarium trispinosum was studied under laboratory conditions at salinities 0-35%o and constant temperatures of 20-30°C. The larval development consists of five zoeal stages and a megalopa. Larvae survived to the first crab stage at salinities between 15 and 35%o with different percentages. At 0, 5 and 10%o, the larvae died within 12-18 hours without moulting to subsequent stages. The highest survival rate was recorded at 20-25%o and 25-30°C with shortest development duration to the first crab stage ranging from 24-28 days. At the highest salinity (35%o), survival rate was gradually decreased with increasing development duration. There were significant differences (P

Flavour components of some processed. fish and fishery products of Japan

A study was conducted to examine the flavour components of some processed fish and fishery products of Japan by gas chromatography-mass spectrometry (GC-MS). In brief the method was to absorb the headspace volatiles at 70°C into the fused silica fibre of needle of the solid phase micro extraction fibre. The absorbed components were injected to the GC-MS. The components were identified by computer matching with library database as well as by authentic standard components. In general the number of flavour components were higher in the processed fish and fishery products (except frozen prawn) than that of the raw fish and prawn. The concentration (quantity) of the f1avour components in processed fish and fishery products was much higher than that of the raw fish and prawn. Smoked salmon and baked salmon possessed double number of flavour components than that of the raw salmon. Smoking resulted the highest number of flavour components followed by baking (grilling) and canning, surimi products (kamaboko and chikuwa), drying and lastly salting. However, freezing and frozen storage resulted loss of flavour components in prawn.

Population structure of the grapsid crab, Helice tridens latimera (PARISI) in the Taiho mangrove, Okinawa, Japan

Grapsid crab Helice tridens latimera inhabiting mangroves, seashores as well as muddy and rocky areas. Ovigerous females were observed from December to May. Juveniles appeared in July and from December to April. In the laboratory they reached 9.50 mm in carapace width 4 months after hatching. It is likely that spawning of this crab occurs throughout the year.

Drosophila subpulchrella, a new species of the Drosophila suzukii species subgroup from Japan and China (Diptera : Drosophilidae)

Drosophila (Sophophora) subpulchrella Takamori and Watabe, sp. nov., of the D. suzukii subgroup in the D. melanogaster species group, is described from Japan and southern China, and compared with its sibling species, D. pulchrella Tan et al. distributed i

Feeding habits of the sesarmid crab Perisesarma bidens (De Haan) in the mangroves of the Ryukyu Islands, Japan

Feeding habits of the sesarmid crab Perisesarma bidens (De Haan) was investigated in the mangroves of the Ryukyu Islands, Japan. Stomach content analysis showed that their diet consists mainly of mangrove leaves fragments, with small amounts of animal, algae and sediment matters, indicating that P. bidens is primarily detritivorous. The consumption rate of P. bidens was investigated under laboratory conditions by offering three different types of Kandelia candel mangrove leaves. Crab survived by eating green, yellow or brown leaves, preferring brown to either green or yellow leaves. Consumption rate of brown leaves was significantly higher when crabs were provided with green, yellow and brown leaves together, than when provided separately. It is considered that the brown leaves have a soft tissue, which is easily torn by the crab chelae and have apparently low C/N ratio. The C/N ratio of faeces, which indicated lower value than that of burrow leaves or sediments, derived from the symbiosis of bacteria in the stomach. The C/N ratio showed that sediments had C/N ratios 2/3 times lower than leaves sequestered in the burrow, indicating that mangrove sediments could have higher nutritional value than mangrove leaves. Perisesarma bidens showed significant consumption rates of mangrove detritus, therefore, it may have the important role as the grazer of mangrove detritus in view of the nutrient cycle in the mangroves.

Stock enhancement in Japan and Taiwan

Stock enhancement has been recognized as one of the essential strategies that can sustain and increase the resources of coastal fisheries. It has been practiced for over a century, with more than 100 species released to date in worldwide programs. Among the countries in Asia, Japan and Taiwan have already established the practice of stock enhancement. Details are given of the main species, number or seedstock produced and released in 1996 in Japan. The species released by the Taiwan Fisheries Research Institute 1976-1995 are also described.

Matrilineal Components and Genetic Relationship of Silkies from China and Japan

Silkie is a famous black-bone chicken breed with beautiful silky feather. The unique medical property of this chicken was recorded in Chinese traditional medicine dictionary about 700 years ago. In this study, we analyzed the mtDNA D-loop sequence variation of 26 Bairong Silkies from Fujian Province, China, together with 100 reported Silkie mtDNAs from China and Japan, and studied their matrilineal components and genetic relationship. A total of 21 haplotypes were detected, which could be assigned to six haplogroups (A-E, G). Among them, haplogroups D and G were exclusively presented in Japanese Silkies and Chinese Silkies, respectively. Chinese Silkies had higher frequency of lineages belonging to haplogroups A, B, and E, and lower frequency of haplogroup C than Japanese Silkies. For the four Chinese Silkie populations, most of samples of Taihe, Chengdu, and Hubei Silkies were grouped in haplogroups A, B, and C, whereas most of Bairong Silkies were grouped in haplogroup E. Five haplotypes were shared by Japanese and Chinese Silkies. The genetic diversity of each Silkie population varied, but the overall diversity of Chinese Silkies was similar to that of Japanese Silkies. Taken together, our results confirmed the genetic connection between Chinese and Japanese Silkies, but also clearly showed that the matrilineal genetic structures of Chinese and Japanese Silkies had some differences.

A technology roadmap of assistive technologies for dementia care in Japan.

The number of elderly people in Japan is growing, which raises the issue of dementia, as the probability of becoming cognitively impaired increases with age. There is an increasing need for caregivers, who are well-trained, experienced and can pay special attention to the needs of people with dementia. Technology can play an important role in helping such people and their caregivers. A lack of mutual understanding between caregivers and researchers regarding the appropriate uses of assistive technologies is another problem. A vision of person-centred care based on the use of information and communication technology to maintain residents' autonomy and continuity in their lives is presented. Based on this vision, a roadmap and a list of challenges to realizing assistive technologies have been developed. The roadmap facilitates mutual understanding between caregivers and researchers, resulting in appropriate technologies to enhance the quality of life of people with dementia.

Transport-determined early growth and development of jack mackerel Trachurus japonicus juveniles immigrating into Sagami Bay, Japan

Oceanographic conditions and transport processes are often critical factors that affect the early growth, survival and recruitment of marine fishes. Sagittal otoliths were analysed to determine age and early growth for 381 jack mackerel (Trachurus japonicus) juveniles from Sagami Bay on the Pacific coast of Japan. Two separate hatching periods ( December and February-March) were identified. They originated from the spawning grounds in the East China Sea. Early growth and developmental rates of December-hatching fish were lower than those for February-March-hatching fish. It is likely that these differences were determined in the Kuroshio Current during transport from the spawning grounds to Sagami Bay, and the lower December water temperatures in the bay. Origin and hatch dates of juveniles in Sagami Bay were in contrast to previous research on Fukawa Bay, where April-or-later-hatching fish from spawning grounds in the coastal waters of southern Japan constituted about half of the juvenile population. Management of these two jack mackerel stocks needs to consider these differences in hatch date composition and spawning origins, as these differences could affect early growth and subsequent mortality.

Morphological description of two bucephalid trematodes collected from freshwater fishes in the Uji River, Kyoto, Japan

The morphology of two species of bucephalids (Bucephalidae; Digenea; Trematoda), which since 1999 has caused a fish disease at the Uji River, Kyoto Prefecture, Japan, is described. Parabucephalopsis parasiluri Wang, 1985 was first recorded in the Uji River in 2000, and Prosorhynchoides ozakii (Nagaty, 1937) in 2005. The definitive host of both species is the Lake Biwa catfish (Silurus biwaensis), and the second intermediate hosts include many fish species from several families. P. parasiluri is an introduced parasite that invaded with its first intermediate host, golden mussels (Limnoperna fortunei), from the Asian continent. P ozakii may also be an introduced species, although its first intermediate host has not been identified. (C) 2007 Elsevier Ireland Ltd. All rights reserved.