Study on Mitochondrial DNA Cytochrome b Gene of Chinese sea bass, Lateolabrax sp.

参考鳗鲡等鱼类线粒体 DNA序列进行了中国花鲈线粒体 DNA细胞色素 b基因片断的引物设计、PCR扩增及其序列测定。得到中国花鲈的碱基序列为 4 10 bp,其 A、T、G、C含量分别为 10 1bp(2 4 .6 3% )、112 bp(2 7.32 % )、72 bp(17.56 % )、12 5bp(30 .4 9% ) ,与鳗鲡等其他鱼类相同基因片断序列碱基含量相似。

Preparation of edible powder from Jawla (Acetes sp.) prawns

Four methods were employed for the preparation of prawn (Acetes) powder in this study. The analytical characteristics and bacteriological quality of the edible powders are presented for each method.

Isolation of Salmonella larochelle for the first time in India

The isolation of a new serotype, S. larochelle (6, 7: eh:1, 2), is reported in this communication. This serotype has not so far been reported from any source in this country. The serotype was isolated on November 27th, 1979 at Bombay from a market sample of frozen frog legs intended for domestic consumption.

Studies on isolation of salmonella from sea foods 1. Comparison of enrichment and selective media for recovery of salmonellae from fish

Three enrichment broths and six plating media were compared for efficiency of detection Salmonella in the presence of numbers of Coliforms (10super(5)/ml) and proteus (10super(3)/ml) from artificially inoculated fish samples. Recovery experiments Salmonella anatum, S. typhimurium and S. enteritidis indicated that the two enrichment broths Dulcitol Selinite (DSE) and Selinite Cystine (SC) were equally efficient. Further, the viability of Salmonella, inoculated into fish muscle and kept at 4°C for 48 hours, was found to be not affected by the low temperature storage. Selective plating media like Xylose Lysine Deoxycholate agar (XLD), Brilliant Green Sulphadiazine agar (BGS) and Brilliant Green agar (BG) were found to be superior in performance to Salmonella-Shigella agar: (SS) and Bismuth Sui phite agar (BiS).

Technological aspects of preservation and processing of edible shell fishes V. Cold storage changes in mussels (Mytilus edulis) and clams (Villortia [i.e. Villorita] sp.)

The changes in chemical, bacteriological and organoleptic qualities of mussels and clams during freezing and subsequent frozen storage have been studied in relation to the holding time in ice prior to freezing and the shelf-life of the product is determined.

Iced and frozen storage of squid (Loligo sp)

The iced and frozen storage characteristics of squid (Loligo sp.) are discussed. Squid can be kept in ice in an acceptable condition for a maximum period of 2 days. Frozen squid can be stored for a maximum period of 15 weeks at -l8°C, which can be extended up to 19 weeks by suitable treatment.

Ice storage studies of Kati (Pellona sp.)

Studies were carried out on the effect of ice storage on the composition of kati (Pellona sp.). On the basis of biochemical, bacteriological and organoleptic valuations, it was observed that kati can be stored in ice for a period of 9 days without appreciable loss in overall quality.

Studies on depuration of live clams (Villorita sp.)

Live clams collected from their natural beds were depurated by starving them in water. Water from their natural environment, potable water from municipal water supply and sodium chloride solution made up to the strength of natural brackish water as well as all these chlorinated at 5 p.p.m. level were used. The acid insoluble ash could be brought down to insignificant level by depuration in natural water for a period of 16-18 h. Bacterial quality of the meat also could be improved by this method. Chlorination of the system at the end of depuration further improves the bacterial quality of the meat.

Isolation of Salmonella roan for the first time in India

The isolation of Salmonella roan for the first time in India is reported.

Rapapport's broth, a better enrichment medium in the identification of Salmonella from processed frog legs

Live clams (Villorita cyprinoides) collected from their natural beds were packed in different ways like dry pack, tray pack, in oxygenated water (wet pack) and depurated samples in wet pack. It was found that the packaging in l kg lots in 200 gauge polythene bags with oxygen at a temperature of 20°C could keep them live for 4 days. In tray pack without oxygen and water they can be kept alive for 3 days at 20°C. Temperature seems to be the critical factor in the transportation of live clams. At room temperature both dry and wet pack can be kept for 24 h only. Depuration technique does not appear to be useful in prolonging the storage life of clams in live condition as percentage mortality is more at 48 h both at 20°C and room temperature compared to the non-depurated samples.

Frozen storage studies of composite fish mince drom dhooma (Sciaenid sp.) and lactarius (Lactarius lactarius)

Fish minces from dhoma and lactarius were mixed in the ratio of 40:60 respectively, and quick frozen along with individual minces at -40°C and stored at -20°C. Shelf life was evaluated by following biochemical, physical and organoleptic changes occurred during storage up to 44 weeks. Rapid decreases were noted in water soluble nitrogen and salt soluble nitrogen fractions during the initial period of 16 weeks. A good correlation was observed between changes in salt-soluble nitrogen and organoleptic evaluation. The minces were in good and acceptable condition up to 32 weeks of storage.

The biology and control of Caligus sp., an ectoparasite of the adult milkfish Chanos chanos Forskal

One unidentified species of copepod belonging to the genus Caliqus of the family Caigidae was found to infest the adult milkfish broodstock. To control the parasites infesting the adult milkfish, tests were made using the chemical (2,2,2-trichloro-1-hydroxyl)-phosphonic acid-dimethylethol (Neguvon) at a concentration of 0 . 25 ppm. It is noted that a concentration of 0 . 25 ppm of Neguvon maintained for 12-24 hours in the sabalo-containing tanks in a closed water system but with aeration is effective in controlling the parasites. Fish mortality during the experiment was due to inadequate aeration in the tanks.

Nitrogen fixing bacteria, Azotobacter sp. in aquatic sediment

Non-symbiotic, free living, nitrogen fixing bacteria, Azotobacter sp. was estimated in sediments of estuarine, marine, backwater and mangrove environments of Portonovo. Number of colony forming units (CFU) of Azotobacter sp. was less (5 to 27 cells/g of dry sediment). CFU of total heterotrophic bacteria (THB), actinomycetes and fungi were between 4.1x10 super(6) and 4.5x10 super (7), 0.8x10 super(5) and 4.9x10 super(5), 1.1x10 super(5) and 3.8x10 super(5)/g respectively. Mangrove sediments contained more CFU of the above microbial groups.

Isolation of Salmonella braenderup (6, 7:e, h:e, n, z (sub15)) from Mussel meat

A brief account is given of the morphology, biochemistry and serology of Salmonella braenderup isolated from mussel meat, obtained from fish markets in Calicut, India. Possible implications regarding human salmonellosis are also considered.

Isolation of Salmonella agona (4, 12:f, g, 5:-) from commercial frozen boiled clam meat

Details are given of the morphological, biochemical and serological characteristics of a specimen of Salmonella agona isolated from a sample of frozen boiled clam meat (Villorita cyprinoides) processed in a factory at Cochin. Possible association of this serotype with human salmonellosis is considered briefly.