Pyridoxine and survival of tilapia (Sarotherodon mossambicus Peters)

Pyridoxine requirements of tilapia (Sarotherodon mossambicus Peters) were studied in two separate experiments using casein-based diets. In Experiment 1, fish on pyridoxine supplemented diet (14.0mg/100g diet) showed no adverse symptoms and remained healthy while fish on a pyridoxine-free diet showed abnormal behaviour with high mortality. Graded dietary pyridoxine (0.13 to 3.52mg/100g diet) was used in Experiment 2. Lower dietary supplementations of pyridoxine resulted in reduced weight increase, high mortality, high ratio of serum glutamate-oxal-acetate transaminase glutamate-pyruvate transaminase, and reduced blood sugar. The results suggest the dietary requirement of pyridoxine may be between 0.5g and 1.17mg/100g diet; higher supplementations did not appear to confer any further benefits

Oceanographic Profiling Observations MOCE-4 Cruise: 26 January to 12 February 1998

This report contains results from the fourth cruise of the MODIS Optical Characterization Experiment (MOCE). Also resented are oceanographic data from two MOBY maintenance cruises L-20 and L-25. The MOCE4 cruise was the first NOAAINESDIS-Ied SeaWiFS Initialization cruise during which a variety ofspectroradiometric observations ofthe upper water column and atmosphere were made by investigators from NOAA, the University of Miami, CHORS and MLML. Data presented in this report were obtained by oceanographic CTD profiler: salinity, temperature, dissolved oxygen, beam attenuation and chlorophyll-a fluorescence~ and by water samplers: total suspended matter and suspended organic carbon and nitrogen, salinity and dissolved oxygen. (PDF contains 142 pages).

The dusky rockfishes (Teleostei: Socrpaeniformes) of the North Pacific Ocean: resurrection of Sebastes variabilis (Pallas, 1814) and a redescription of Sebastes ciliatus (Tilesius, 1813)

The dusky rockfish (Sebastes ciliatus) of the North Pacific Ocean has been considered a single variable species with light and dark forms distributed in deep and shallow water, respectively. These forms have been subjected to two distinct fisheries separately managed by federal and state agencies: the light deep form is captured in the offshore trawl fishery; the dark shallow form, in the nearshore jig fishery. The forms have been commonly recognized as the light dusky and dark dusky rockfishes. From morphological evidence correlated with color differences in some 400 specimens, we recognize two species corresponding with these color forms. Sebastes ciliatus (Tilesius) is the dark shallow-water species found in depths of 5−160 m in the western Aleutian Islands and eastern Bering Sea to British Columbia. The name Sebastes variabilis (Pallas) is resurrected from the synonymy of S. ciliatus to apply to the deeper water species known from depths of 12−675 m and ranging from Hokkaido, Japan, through the Aleutian Islands and eastern Bering Sea, to Oregon. Sebastes ciliatus is uniformly dark blue to black, gradually lightening on the ventrum, with a jet black peritoneum, a smaller symphyseal knob, and fewer lateral-line pores compared to S. variabilis. Sebastes variabilis is more variable in body color, ranging from light yellow to a more usual tan or greenish brown to a nearly uniform dark dorsum, but it invariably has a distinct red to white ventrum. Synonymies, diagnoses, descriptions, and geographic distributions are provided for each species.

Gill-damage in netted Tilapia mossambica Peters

Tilapia mossambica taken with gill-nets are often found with their gills damaged. Gill-filaments may be partly or completely lost; sometimes even the gill-arches are all missing (Plate IA). The operculum is usually undamaged but may have its posteroventral border slightly frayed (Plate IB). For comparison normal fish are shown in Plates IC and ID. Incidence of gill-damage increases rapidly with length of time the nets remain in the water; in the Parakrama Samudra a mere 2-3 hour interval between setting and lifting results in 5 to 20% of the fish being damaged.