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This study was performed to determine the prevalence, antimicrobial susceptibility, and genetic relatedness of Salmonella enterica subsp. enterica and Campylobacter spp. in poultry meat, and to analyze the association of genetic types of these bacteria with their geographical distribution and antimicrobial resistance profiles. Salmonella and Campylobacter isolates have been detected, respectively, in 54 and 71 samples out of 100 samples tested. Nine Salmonella serotypes were found, including S. enterica subsp. enterica serovar Infantis (33%), Schwarzengrund (12%), Manhattan (9%), and others. Campylobacter jejuni and C. coli were detected in 64 (64%) and 14 (14%) samples, respectively. S. enterica subsp. enterica isolates were very frequently resistant to tetracycline (78.3%) and streptomycin (68.3%). Many C. jejuni and C. coli isolates were resistant to sulfamethoxazole/trimethoprim (90.5%), nalidixic acid (47.3%), ampicillin (45.9%), and ciprofloxacin (40.5%). Cluster analysis was performed for the Salmonella isolates using pulsed-field gel electrophoresis (PFGE) data. For Campylobacter isolates, the cluster analysis was based on both PFGE and comparative genomic fingerprinting. The molecular typing results were compared with the information about antimicrobial resistance and geographical locations in which the poultry meat was produced. This analysis revealed that C. jejuni strains with a particular genotype and antimicrobial resistance profile are spreading in specific areas of Japan.

Salmonella is a major causative agent of food borne diseases. Recently, monophasic strains of Salmonella, such as S. enterica 4: i: -, have been frequently reported. Here, we investigated the genetic background of S. enterica 4: b: - using multilocus sequence typing (MLST) and pulsed-field gel electrophoresis. A total of 10 strains of S. enterica (I) 4: b: - were examined and compared with 34 strains including serovar Paratyphi B and Paratyphi B var Java, Schleissheim, and II b: -. All I 4: b: - strains were negative for hin which encodes an invertase that converts the H phases, and six were also negative for fljB, which encodes the second phase of the H antigen. An MLST analysis identified 12 sequence types (ST) and 6 ST complexes (STC) from the 44 strains. A clustering analysis of PFGE patterns almost corresponded to the STC. The monophasic I 4: b: - strains were assigned to 3 STCs (19, 32 and 155), corresponding to those of Paratyphi B var. Java or a monophasic strain according to the data of this and previous studies. These findings suggest that the monophasic strains examined in this study might have been derived from multiple clones of Paratyphi B var Java. This study shows the usefulness of molecular typing as complementation tools of the conventional serotyping system.

The appropriate water velocity in artificial burrows for theJapanese crayfish species Cambaroides japonicus was studied.An experimental system of two artificial burrows (burrows A and B)of the same size was set in a large tank. The velocity of burrowA was 0 cm/s and that of burrow B was varied andset at 0 cm/s, 5 cm/s, 10 cm/s,20 cm/s and 30 cm/s. The selectionof these two burrows by C. japonicus was observed. No animalsselected burrow B significantly more than burrow A above 10 cm/s.At 20 cm/s, some crayfishes were swept away andcould not return to burrows because of the high water velocity.At 30 cm/s, most animals were swept away. We concludethat the appropriate water velocity for the suitability of artificialburrows and the immediate foraging area adjacent to the burrowsshould be as low as 5 cm/s.

Based on four male specimens from Sagami Bay, we present a brief description of Paralebbeus zygius Chace, 1997. This is the second record of the species, which is new to the Japanese fauna. All of the specimens were obtained from small chambers in hexactinellid sponges collected more than a century ago. Morphological variations of some important characters are discussed. Une courte description de Paralebbeus zygius Chace, 1997 est presentee a partir de quatre specimens mâles recoltes dans la baie de Sagami. Cette espece, signalee pour la seconde fois depuis sa description, est nouvelle pour la faune japonaise. Les specimens etudies ont ete trouves dans de petites cavites d'eponges Hexactinellides, recoltees il y a plus d'un siecle. Les variations morphologiques de quelques caracteres importants sont discutees.

sampled and preserved in 100% ethanol prior to analyses in the laboratory. The euphausiid crustacean, Pseudeuphausla latlfrons (G. O. Sars, 1883) ap peared to be the dominant species among the stranded animals, comprising 83.5% of the sample. A small number of other zooplankters were associated with the stranded P. latlfrons, including Euphausla glbboldes Ortmann, 1893, Sagltta sp. (? spp.), and several species of hyperiid amphipods (Lestrlgonus spp., Themlsto gra cllipes Norman, 1869), etc. (table I). P. latlfrons is a neritic species of the tropical and subtropical Indo-Pacific and usually inhabits the upper 100 m throughout the

Lethal limits of high temperature were studied to clarify the effects on the survival of the endangered Japanese crayfish species Cambaroides japonicus and the alien species Pacifastacus leniusculus. After the acclimation period for 2 weeks at 16°C, the temperature was raised at a rate of 1°C per week. As a result, the ultimate upper lethal temperatures of C. japonicus and P. leniusculus were 27.0 and 31.1°C, respectively, and the lethal temperature for P. leniusculus was significantly higher than for C. japonicus. The natural distributions of these two species are discussed in terms of the temperature tolerance.

SUMMARY: Preference for artificial burrows by the endangered Japanese crayfish species Cambaroides japonicus was studied to improve its cultivation. The occupation of artificial burrows, which were made from straight polyvinyl chloride pipes of different internal diameters (Y, mm), by crayfishes of different total lengths (X, mm) was significantly (P < 0.001, n = 56) described by a linear regression: Y = 0.49X + 3.42 (19.0 ≤X≤ 70.2). Among burrows of different lengths [crayfish total length (TL) × 1, × 2, × 3, and × 4], crayfishes significantly preferred burrows that were greater than TL × 3 (P < 0.001, n = 588).

Based on material col­ lected from shallow hydrothermal vent fields in Kagoshima Bay, southern Japan, a neAV species of the subfamily Pontoniinae, Periclimenes thertnohydrophiluSy is described and il­ lustrated. A combination of several char­ acters distinguishes the present new^ spe­ cies from all other members of this genus. A short and narrow rostrum w^ithout basal crest, an isolated epigastric spine, a submarginal antennal spine and a long carpus of the second pereopod are char­ acteristics of the new^ species. The rela­ tionship betw^een this shrimp and host tube w^orms is briefly discussed.

Two new species of the crangonid genus Philocheras, P. gemmaceus and P. fujinoi, are described and illustrated from East Asian waters. Both were previously treated insufficiently; one was erroneously referred to Pontophilus candidus Kemp, and the other, Pontophilus sp. of Fujino and Miyake (1970), was left unnamed, because only a single, mutilated specimen was available. The first new species, P. gemmaceus, is more closely related to P. planoculminus Bruce than to P. candidus (Kemp). Philocheras gemmaceus is readily distinguishable from them by the combination of the wider rostrum, the presence of the median gastric spine in females and the bud-like appendix interna of the endopod of the second to fifth pleopods in males. More complete material from the northern South China Sea confirms the validity of the latter new species, P. fujinoi, which is distinguished from other members of the genus by the presence of one gastric spine, three frontal spines on the postorbital carina, two spines situated ...

A new species, Alpheus kagoshimanus , collected from considerable depths of Kagoshima Bay, is described and illustrated, including its live colouration. It belongs to the brevirostris species-group. A distinct pterygostomial spine readily distinguishes the new species from all other members of this group as well as from all the known species of the genus Alpheus . Apart from this character, it bears much resemblance to A. acutocarinatus De Man and A. migrans Lewinsohn & Holthuis in having the remarkably long first pereopods and the middorsal carina of the carapace with a small, interrupted tubercle. More slender first pereopods with 2-8 movable spines on the ischium and the longer first carpal article of the second pereopod are the other characters of the new species. Une nouvelle espece, Alpheus kagoshimanus , recoltee a grande profondeur dans la baie de Kagoshima, est decrite et illustree, y compris sa couleur a l'etat vivant. Elle appartient au groupe brevirostris . La presence d'une epine pterygostomienne distincte la distingue nettement des autres membres de ce groupe comme des autres especes du genre Alpheus . Ce caractere mis a part, l'espece ressemble beaucoup a A. acutocarinatus De Man et A. migrans Lewinsohn & Holthuis par les premiers pereiopodes remarquablement longs et un petit tubercule emousse sur la carene mediodorsale de la carapace. Les premiers pereiopodes plus greles, portant 2-8 epines mobiles sur l'ischion et le premier article du carpe du second pereiopode plus long sont les autres caracteres distinctifs de la nouvelle espece.

Based on several type specimens and material collected from various localities, the East Asian species of Crangon are revised. C. affinis De Haan, 1849, C. propinquus Stimpson, 1860, C. dalli Rathbun, 1902a, C. hakodatei, Rathbun, 1902b, C. cassiope De Man, 1906, C. amurensis Brashnikov, 1907 and C. uritai new species are recognized. C. affinis is given full specific status. A neotype is designated for C. propinquus. C. septemspinosa forma amurensis and C. septemspinosa forma anivensis are assigned to C. amurensis. The taxonomic status of C. dalli, C. hakodatei and C. cassiope is clarified by the examination of the type specimens and/or topotypic specimens. Each species is diagnosed and illustrated. C. uritai, which had been confused with C. affinis, is fully described and illustrated. Affinities and distribution of these seven species are discussed and a key is provided., Crustacean research No.28, pp. 62-103; 1999

西日本に分布する両側回遊性ヌマエビ類5種,ヒメヌマエビCaridina serratirostris,トゲナシヌマエビC.typus,ミゾレヌマエビC.leucosticta,ヤマトヌマエビC.japonica,およびヌマエビ(小卵型)paratya compressa compressaの第1・第2ゾエア期幼生について,腹部の色素胞の位置と形状を観察し,それらの出現傾向を記載した.さらにこれを利用して第1・2ゾエア期幼生の種を識別する方法を示し,検索表を作成した., The abdominal chromatophores of the first and second zoeae were examined in five amphidromous atyid shrimps, which are widely distributing in southwest Japan: Caridina serratirostris De Man, C. typus H. Milne Edwards, C. leucosticta Stimpson, C. japonica De Man, and Paratya compressa compressa (De Haan) (small egg type). Chromatophore distribution pattern of larvae was found to be an effective character to identify respective species., 甲殻類の研究=Crustacean research. 1995, 24, p.194-202

A new genus of the crangonid shrimps, Syncrangon, is proposed for Crangon angusticauda De Haan, 1849 and C. (Sclerocrangon) angusticauda var. dentata Balss, 1914, both from East Asian waters. The new genus is readily distinguished from all known genera of the Crangonidae by the flattened middorsal carina and the deep groove on each lateral side of the middorsal carina on the third to sixth abdominal somites. Syncrangon angusticauda new combination has previously been assigned to the genus Metacrangon, while S. dentata new combination has not been reported since the original description. These two species are easily distinguished from each other by many characters, especially the rostral and abdominal features. They are redescribed and illustrated in detail.

A new species, Lvsmata dispal~ was found from a collection of shrimps from the Dampier Archipelago. It bears an unequal second pair of pereopods, with the carpus having more than 30 subsegments, and a com pa rati vel y long 10C('ri te. The combi na lion of these cha racters distinguishes L dispar immediately from all known species. A full description of this species and a list of a further eight species of seven genera of the family Hippolytidae, with short notes on three members new to Australian waters, is presented.

In June, 1984, a large-scale outbreak of type A botulism occurred in 14 different prefectures in Japan, involving 36 cases and 11 deaths, due to consumption of vacuum-packed ‘karashi-renkon’ (deep-fried mustard-stuffed lotus root). The onset of symptoms ranged from June 9th through July 28th and many batches of ‘karashi-renkon’, having been manufactured by a factory during a period of three weeks from June 5th to June 25th, were found to be contaminated with type A spores. Type A spores (1.0 × 104 cfu/g) experimentally inoculated into the mustard-miso stuffing [water activity (aw) 0.92, pH 5.0, NaCl 5.7%] did not multiply. By adjusting the stuffing to aw 0.98 (pH 5.4) growth of type A was still inhibited. When the stuffing with elevated aw and pH was heat-treated for 60 min at 80°C or autoclaved, it supported growth of Clostridium botulinum type A as indicated by the achievement of toxin levels higher than 105 LD50/g. When mustard-miso was stuffed into the holes of lotus roots and refrigerated overnight or a longer period, both aw and pH of the stuffing increased to 0.98 and 5.3, respectively. The changes were apparently due to dialysis between the stuffing and the lotus root. This refrigeration process was actually performed at the plant, where the incriminated foodstuff was manufactured. The dialyzed mustard-miso stuffing, when heat-treated, supported the growth of type A organisms. Thus, we substantiated the possibility of primary multiplication of C. botulinum type A in mustard-miso stuffing subjected to refrigeration in lotus roots and then heat-treated.

Based upon 114, 000 specimens of prawns and shrimps collected by several small type trawlers from eight localities of the Kii Strait along Wakayama Prefecture, their species composition and comparative abundance as well as the population movement of some commercially important species are revealed. They consisted of 20 species of Penaeidae and 17 species of 6 caridean families. Of these, Metapenaeopsis palmensis is new to Japanese fauna, and Periclimenes tosaensis, Processa kotiensis and Nikoides sibogae prove to be recorded for the first time from the Kill Strait. The dominant species is Trachypenaeus curvirostris in the northern part, Metapenaeopsis barbata from north to middle of the strait, M. palmensis in Tanabe Bay only and Plesionika izumiae in the central part of the strait. Other characteristic species, though not so common, occur in each locality. The two dominant species, T. curvirostris and M. barbata, decrease in number from spring to summer, but there seem to be two peaks of the fluctuation of their catches. One peak appears from spring to summer and may depend upon an increase of the body weight and the other is probably caused by the new recruitments in autumn.

Two specimens of the nephropid genus Acanthacaris collected from southwest of Kyushu, Japan were recently examined. They proved to belong to A. tenuimana Bate, which constitutes the first record for the Japanese fauna. The present paper presents short notes on these specimens, showing the range extension and some morphological variations of this rare species. The material is deposited at the museum of Shimonoseki University of Fisheries (SUF).

Based upon the material from the Kii Strait, the taxonomy and biology of Metapenaeopsis palmensis (HASWELL) are presented. It is the fourth stridulating species in Japan and is separated from the three other species by having 6-12 ridges, the short inner intermediate strip of the petasma and a pair of large bosses on the sternite of fourth pereiopods in females. Sex ratio is approximately 1:1, and females are larger than males. M. palmensis is abundant in shallow waters less than 30m of Tanabe-Bay, but becomes abruptly rare in deeper waters of the strait, as well as in the far north localities. This species seems to be well settled only in Tanabe-Bay and has the long- and short-term generations. The spawning season continues from June to September and new recruitments occur from July to November. It is one of the commercially important prawns and accounted for about 16-19% of the total catches of small-type trawl fisheries in 1972-1975.

Pandalus gracilis Stimpson, which has been synonymized with P. hypsinotus Brandt, is revived as a good species. Both species occur in the Japanese fauna. It is more closely related to P. prensor Stimpson than to P. hypsinotus. The three species show a number of morphological differences; furthermore P. prensor is the smallest of the three, and P. hypsinotus the largest. The life span of P. hypsinotus is longer than that of P. gracilis. P. gracilis is known to occur rathe abundantly in the southern part of the Sea of Japan, but the commercial value is not high, because of the small size.

The present paper reports on some notes and descriptions of the hippolytid shrimps found chiefly in the coral reefs of Amami-oshima, north of the Ryukyu Islands, and of the Palau Islands. The materials dealt here are referable to six species belonging to three genera of the family Hippolytidae. Holthuis (1953) published the enumeration lists of the decapod and stomatopod Crustacea from the Pacific coral islands, and described the following four species, Saron marmoratus (Olivier), S. neglectus de Man, Thor maldivensis Borradaile and T. paschalis (Heller). Among these the first three species are treated herewith. Three others are identified with T. amboinemis (de Man), Thor sp. and Lysmata dentata (de Haan) respectively.

Summary The net assimilation rate (E) of a plant population (the mean rate of increase in total dry weight per unit leaf area, measured over a period of 1 or 2 weeks), represents the excess of the rate of photosynthesis of the leaves (P) over the rate of respiration of the whole plants (R), both expressed per unit leaf area (E=P—R). To determine P, photosynthesis was prevented on some days during the experimental period by shading plants, and the effect on E was measured. The plants were held in a controlled environment to ensure that external conditions affecting photosynthesis were the same on all days and effects on change with age in the rate of photosynthesis were avoided by appropriate distribution of the shading days. With these precautions, E was linearly related to n, when n (the number of days when photosynthesis was permitted in an experimental period of 15 days) ranged from 15 to 9. The regression coefficient b of E on n measures the contribution of 1 day's photosynthesis to E, so the photosynthetic component P of EN,the net assimilation rate when photosynthesis is permitted every day in an experimental period of N days, is given by Nb. The respiratory component, R,is estimated by the difference EN—P, or graphically by extrapolating the regression line to n= 0. This method showed that young sugar-beet plants had a greater net assimilation rate than barley plants solely because they had a greater rate of photosynthesis of the leaves; the values of the rate of respiration of whole plants for the two species were identical.

Asimple technique for obtaining the well-spread metaphase chromosomes from the regeneration blastema of a prawn is described. The removed regeneration blastema of Penaeus(Marsupenneus)japonicus was treated with a slightly modified air-drying method. The diploid number of chromosomes of this prawn was 86.