Seasonal foods, gonadal maturation, and length-weight relationships for nine fishes commonly captured by shrimp trawl on the Northwest Gulf of Mexico Continental Shelf

Recent emphasis on ecosystem approaches to fisheries management renews interest in, and the need for, trophic information about fish communities. A program was started in 1980 at the National Marine Fisheries Service Galveston Laboratory to develop a trophic database for continental shelf fishes. Collections were made during 1982-1983 that were processed but never published, yet the data remain valid today for historical purposes and for delimiting food web components within ecosystem assessments. I examined spring, summer, and fall foods in offshore populations of nine common species of trawl-susceptible fishes, with particular reference to predation on commercial penaeid shrimps (Farfantepenaeus and Litopenaeus). Diets were evaluated with the Index of Relative Importance (IRI) which combines the occurrence, number, and weight of each food item. Bank sea bass (Centropristis ocyurus) and bighead searobin (Prionotus tribulus) primarily consumed crabs, more so by larger than smaller fish. Inshore lizardfish (Synodus foetens) was almost entirely piscivorous. Ocellated flounder (Ancylopsetta ommata) consumed fishes, crabs, and stomatopods. Dwarf sand perch (Diplectrum bivittatum), blackwing searobin (Prionotus rubio), rock sea bass (Centropristis philadelphica), southern kingfish (Menticirrhus americanus), and red snapper (Lutjanus campechanus) fed mainly on shrimps. Most fish diets varied with respect to size (age), time of day, area sampled, depth, or season. Rimapenaeus and Sicyonia were the most frequently identified shrimp genera - only five Farfantepenaeus and no Litopenaeus were identified in almost 4,300 fish stomachs. I also examined gonadal development and documented fish length-weight relationships. Ripe gonads were most frequently found during summer in dwarf sand perch, during fall in ocellated flounder and bighead searobin, and during spring for other species, except no ripe red snapper or bank sea bass were collected. Rock sea bass was found to be a protogynous hermaphrodite, while dwarf sand perch is a synchronous hermaphrodite. Only ocellated flounder and southern kingfish exhibited sex-related differences in length-weight relationships. (PDF contains 40 pages.)

Trace metals in common marine foods of the Pacific Coast

Trace metal analysis of 23 species of common Pacific Coast marine foods revealed high cadmium values for Bent-nosed clams (Macoma nasuta), Bay mussels (Mytilus edulis), Bay oysters (Osrtrea lurida), Pacific oysters (Crassostrea gigas), and Littleneck clams (Protothaca staminea). Metals were found to concentrate in the gills, heart, and visceral mass of all 10 species of bivalve mollusks examined. Swordfish (Xiphias gladius) and Salmon (Oncorhynchus tshawytscha) demonstrated the highest cadmium values for fish flesh.

Foods and diets of communities involved in inland aquaculture in Malaita Province, Solomon Islands

Solomon Islands has a population of just over half a million people, most of whom are rural-based subsistence farmers and fishers who rely heavily on fish as their main animal-source food and for income. The nation is one of the Pacific Island Counties and Territories; future shortfalls in fish production are projected to be serious, and government policy identifies inland aquaculture development as one of the options to meet future demand for fish. In Solomon Islands, inland aquaculture has also been identified as a way to improve ood and nutrition security for people with poor access to marine fish. This report undertaken by a Worldfish study under the CGIAR Research Program on Aquatic Agricultural Systems explores the e potential role of land-based aquaculture of Mozambique tilapia in Solomon Islands as it relates to household food and nutrition security. This nutrition survey aimed to benchmark the foods and diets of households newly involved in small homestead tilapia ponds and their neighboring households in the central region of Malaita, the most populous island of all the provinces in Solomon Islands. Focus group discussions and semistructured interviews were employed in 10 communities (five inland and five coastal), four clinics, and five schools.

Diel feeding patterns, rate of gastric evacuation and foods of Indian sandwhiting, Sillago sihama in Mulki estuary, west coast of India

Diel feeding chronology of sandwhiting, Sillago sihama was examined from stomach collections taken during the months of April, July and December'99 in Mulki estuary along Dakshina Kannada coast, India. Significant differences in mean stomach content weight were found between several consecutive 3 hour periods with peak fullness occurring in early morning and evening hours. The rate of gastric evacuation of natural food (crustacea, polychaetes and fish) was measured in the field was best described by an exponential model, with an estimated evacuation time of 8.0 h at a temperature of 28.5 ± 1.2°C. Stomach content analysis indicated that this species is a carnivore on a wide range of benthic, epibenthic and planktonic prey. The principal food items of S. sihama were crustaceans, polychaetes and fish. Fishes less than 100 mm TL preferred mainly crustaceans while larger ones depends on polychaetes, crustaceans and fish. The feeding activity of S. sihama was influenced by tidal cycle.

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).

Freeze drying of fishery products: Part V - Storage characteristics of ready-to-serve freeze dried foods

Behaviour of freeze dried ready-to-serve fish based food preparations during prolonged storage at room temp has been studied and reported in this paper. Storage life of such products under the conditions employed in this study can be reckoned in years at our ambient temps.

Incubation temperature for total bacterial count of frozen sea foods

Effect of incubation temperatures of 37°C ambient and 5-10°C on total plate count of commercial frozen prawns, squids, cuttle fish and froglegs were studied. Results indicate that incubation at ambient temperature gives the best results.

Study of effect Rosmarinus officinalis oil and nisin on the growth of Streptococcus iniae in lab conditions and fillets of rainbow trout (Oncorhynchus mykiss)

Fish are an important part of a healthy diet since they contain high quality protein, but typically present a low fat percent when compared to other meats. Fish is an extremely perishable food commodity. On the other hand, food borne diseases are still a major problem in the world, even in well-developed countries. The increasing incidence of food borne diseases coupled with the resultant social and economic implications means there is a constant striving to produce safer food and to develop new antimicrobial agents concerns over the safety of some chemical preservatives and negative consumer reactions to preservatives they perceive as chemical and artificial, have prompted on increased interest in more ‘‘naturalgreen’’ alternatives for the maintenance or extension of product shelf-life. Particular interest has focused on the potential applications of plant essential oils. However, to establish the usefulness of natural antimicrobial preservatives, they must be evaluated alone and in combination with other preservation factors to determine whether there are synergistic effects and multiple hurdles can be devised. In this study, were evaluated the effects of different concentrations of Rosmarinus officinalis and nisin and storage time (15 days) on growth of Streptococcus iniae GQ850377 in a lab conditions and a food model system (fillets of rainbow trout) in 4 and 8 °C. In addition, we also studied multi factorial effects of four different concentration of rosemary, three different concentrations of nisin, two different levels of pH in 3 temperature 4,15 and 37 °C on log% of S.iniae during 43 days in BHI broth. The results on growth of S. iniae were evaluated using SPSS 20.0 statistical software and analyzed the logarithm of total count of the bacterial by Tukey Test. Results were considered statistically significant when P<0.05. MIC and MBC values of rosemary and nisin were 0.03, 0.075 % and 5, 40 μg/mL, respectively. The growth of S. iniae was effected significantly (P<0.05) by rosemary and nisin and also combination of rosemary and nisin in 4 and 8 °C. Samples treated with 0.135 and 0.405 % of rosemary showed a significant decrease on the growth of the bacteria compared with control sample(P<0.05). The most ١٤٦ inhibitory effects were seen in samples treated with 0.135 and 0.405% of rosemary until 9 days after storage. Also, the synergism effects of rosemary and nisin on the growth rate of bacteria was significant (P<0.05) compared with untreated samples and samples treated with the rosemary or nisin, only. Synergistic effects was observed at concentration of 0.405% rosemary and 0.75 μg/mL nisin in both temprature. Results of this study showed that different concentration of rosemary a significant inhibitory effect (P<0.05) on log% of S. iniae, in BHI broth in pH 5.5 and 7 in 4,15 and 37 °C during 43 days. In concentration of 0% rosemary (control) in pH 5.5 and 7 and 37°C, log% were 1.099 and 3.15, whereas in concentration of 0.015% rosemary were -4/241 and 1.454, respectively. The use of essential oils may improve food safety and overall microbial quality. If essential oils were to be more widely applied as antibacterials in foods, the organoleptic impact would be important. In addition, it is recommended to apply essential oils or their compounds as part of a hurdle system and to use it as an antimicrobial component along with other preservation techniques. Thus essential of R. officinalis with high antibacterial activity selected in this study could be a potential source for inhibitory substances against some food-borne pathogens and they may be candidates for using in foods or food-processing systems.