Effect of electric stimulation on heart beat and body muscle in fish

The effect of AC and DC electric stimulations on the heart-rate and the entire body of Heteropneustis fossillis, Tilapia mossambica and Macrobrachium rosenbergii were studied and presented in kymograph tracings. The reaction of spinal cord in Puntius ticto, Heteropneustis fossilis and Tilapia mossambica to D. C. field was observed to find out its role in electric shocks. A test-check of the electrical resistance of a few species was also conducted. The effect of D. C. and A.C. on the body muscle was found to be the same as that in the case of frog. Different degrees of cardiac slowing were observed in AC and DC. Unbalanced galvanotropic movements were also noticed in spinal fishes.

Effect of frozen storage on the physical properties of corrugated fibre-board master cartons and waxed duplex cartons

Deteriorative changes in physical properties of corrugated fibre-board master cartons and waxed duplex cartons during frozen storage under commercial conditions were studied. Such changes due to prolonged exposure of these boards to moisture in the laboratory, effect of repeated wax-coating on the water resisting capacity of the boards and protection provided by increasing wax contents in the boards against water absorption and consequent deterioration in physical properties are reported.

Studies on the chemical control of psychrophilic bacterial spoilage of fish. 4 - The effect of chemical preservatives on the growth of psychrophilic bacteria isolated from marine fish

Dehydroacetic acid and ammonia were found to be very effective in checking the growth of all the cultures at all concentrations tried. The two nitrofuran derivatives namely, semicarbazone and AF-2 were fairly effective, semicarbazone being more effective than AF-2. Sodium nitrite was found to be totally ineffective against the cultures at all concentrations tried.

Effect of incubation period on plate count of raw ices and frozen fish

The total viable counts were estimated in one hundred and sixty five samples of raw, iced and frozen fish using incubation periods of 24, 48, 72 and 96h. For raw fish, 24h and for iced and frozen fish 48h incubation of the plates were found to be adequate. Variation between samples was significant at 1% level for raw iced and frozen samples.