Journal of Fisheries (University of Rajshahi)
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Nutritional evaluation of soybean meal after fermentation with two fish gut bacterial strains, Bacillus cereus LRF5 and Staphylococcus caprae CCF2 in formulated diets for Labeo rohita fingerlings
Get PDFTwelve isonitrogenous (35 % crude protein) and isocaloric (18.0 kJ/g) diets were formulated incorporating raw and fermented soybean meal (SBM) at 15%, 30%, 45% and 60% levels by weight. Two phytase-producing bacterial strains, Bacillus cereus LRF5 and Staphylococcus caprae CCF2 isolated from the gut of adult Labeo rohita and Catla catla, respectively were used for fermentation of SBM. Fermentation of SBM was effective in reducing the anti-nutritional factors, trypsin inhibitor and phytic acid and enhancing protein, lipid and mineral concentration. The response of L. rohita, fingerlings (initial weight 3.33±0.07 g) fed the experimental diets for 100 days was compared with fish fed a fish meal based diet. In terms of growth, feed conversion ratio and protein efficiency ratio, diet S7 containing 45% SBM fermented with B. cereus LRF5 resulted in a significantly (P<0.05) better performance of fish. The overall performance of L. rohita fed fermented SBM incorporated diets was better in comparison to those fed raw SBM incorporated diets. The apparent digestibility of nutrients and minerals was significantly (P<0.05) higher in fish fed diet S7. The maximum deposition of protein in the carcass was recorded in fish fed diet S7. Diets containing fermented SBM reduced fecal P levels. 
Enhancement of growth performance and hematological changes in rainbow trout (Onchorhynchus mykiss) alevins fed with Bifidobacterium bacteria
Get PDFThe study of probiotic application as an important rearing strategy was started more than 30 years ago and most of these studies were carried out to increase growth and survival of larvae. Effect of Bifidobacterium animalis PTTC-1631 and B. lactis PTTC-1736 as probiotic supplement has been studied on growth performance and hematological changes on rainbow trout, Oncorhynchus mykiss alevins with initial body weight of 0.583 ± 0.197 g. The commercial diet was supplemented with graded levels of probiotics (1×107, 2×107 and 3×107 CFU g-1 dry feed) to obtain 3 sets of experimental diets (T1, T2, and T3 respectively) and fed four times a day for 60 days. T1 alevin showed the best growth performance in terms of specific growth rate, weight gain, metabolic growth rate, feed conversion ratio and survival rate. The highest red and white blood cell concentrations were noticed in fish fed T2 and T3 diets, respectively, no significant difference was observed in hemoglobin content. T1 showed the significant elevation of serum biochemical parameters and reduction of cortisol level. The results of present study might suggest likely positive effects of probiotic supplements with concentration of 1×107 CFU g-1 dry feed on growth and hematology on rainbow trout alevins
Fisheries education in Sri Lanka: current status, constraints and future outlook
Get PDFSustainable utilization of the fishery resources along with manpower is one of the most important aspects of fisheries science. Although a huge manpower is available in the fisheries sector, lapses in knowledge also prevalent in various subsections of fishery related occupations. In this scenario, this paper attempts to evaluate the various levels of fisheries education in Sri Lanka. It has been observed that clear demarcation of the level of fisheries education such as undergraduate, postgraduate, and basic level exists in Sri Lanka. Although a low level of student enrolment, university education of fisheries and aquaculture is at satisfactory level. Expansion of fisheries education for basic levels such as education of fisherwomen needs to be improved. Scientific dissemination of knowledge by published works such as journals should further be expanded and indexing of those journals in reputable and reliable databases is needed. Several constraints in Sri Lankan fisheries education such as inadequate funding, low level of student enrolment, quality of the students and less cooperation with industries etc. were also identified. Therefore, finding possible solutions to these issues is necessary to ensure the quality of the education in Sri Lanka
New record of the flasher scorpionfish, Scorpaenopsis macrochir Ogilby, 1910 (Scorpaeniformes, Scorpaenidae) from Indian waters
Get PDFBased on two specimens of the flasher scorpionfish, species of Scorpaenopsis macrochir Ogilby, 1910 (85-96 mm, TL) collected from the Visakhapatnam coastal waters, India, we described S. macrochir as the new record from Indian waters. This species is characterized by having 12 dorsal spines, medial surface of pectoral fins with a black subterminal band along entire margin of fin; supraorbital spine ending in a single spinous point and unserrated ocular spines. Nasal spines usually divided into two to six small points. The present study describes full description of the species with illustrations
Effect of treatments and washing cycles on the quality of Nile tilapia (Oreochromis niloticus) protein concentrate
Get PDFThe extraction of proteins from wastes reduces production costs and environmental pollution. The aim of this work was to evaluate the effect of two treatments involving decanting/sieving or centrifugation and the number of washing cycles on the quality of protein concentrate obtained from mechanically separated meat (MSM) of Nile tilapia (Oreochromis niloticus). Results were analyzed in terms of final yield and proximate composition (moisture, protein, fat and ash) after each washing cycle. Moisture did not vary statistically with the treatments and after the third washing cycle. However, the process involving centrifugation was more efficient for protein concentration because the final protein content increased 2.0 folds (79.82%, dry basis) and fat decreased 6.1 folds (8.29%, dry basis). After four washing cycles, it was obtained a protein concentrate with 79.82% protein, 8.29% lipid and 0.45% ash (dry basis), and 80.0% yield, using the centrifugation procedure. Visual whiteness was highly improved after four washing cycles using both processes. It was concluded that the centrifugation process with four washing cycles was the most appropriate method for producing protein concentrate from MSM of Nile tilapia
Estimates of length-based population parameters of the skipjack tuna, Katsuwonus pelamis (Linnaeus, 1758) in the Andaman waters
Get PDFThe exploitation of Katsuwonus pelamis in Andaman waters is meagre compared to its total landings in India. As the population parameters of this species has not been attempted in these waters, an attempt has been made here to estimate the population parameters of K. pelamis based on the length frequency data collected from local fishing boats operating from Junglighat Fishing Harbour, Port Blair, Andaman Islands from January to December 2014. A total of 704 specimens ranging from 16.5 to 71.0 cm fork length were taken for analysis. The parameters L∞, K and t0 were 74.55 cm, 0.59/year and –0.21 respectively. The von Bertalanffy growth equation for K. pelamis is Lt = 74.6[1 – e–0.59(t+0.214255)]. The recruitment pattern was unimodal. The recruitment period was from July – October. The longevity of the species was calculated as 4.9 years. After 1st, 2nd, 3rd and 4th year the length attained by the species is 38.1, 54.4, 63.4 and 68.3 cm respectively. The mortality parameters were Z=2.07, M=0.93, F=1.14 and exploitation ratio was 0.55. The virtual population analysis for K. pelamis indicated that fishing mortality starts at 41–50 cm class interval and it continues henceforth and was maximum at 61–70 cm and decreased thereafter
Length-weight relationship and condition factor of Tade gray mullet, Chelon planiceps (Valenciennes, 1836) from Hooghly-Matlah Estuary, West Bengal, India
Get PDFTade gray mullet (Chelon planiceps) forms a lucrative fishery in the Hooghly-Matlah estuarine system. During eight months of investigation 232 specimens were examined to study length-weight relationship and relative condition factor (Kn). The length and weight of fish was varied from 41 to 283 mm and 0.81 to 208 g respectively. Two length-weight relationship equations were obtained from the analysis, W=0.0000397L2.952 for <187 mm size group and W=0.0000406L2.834 for >187 mm size group. The size at first maturity was recorded as 187 mm. The b value was not significantly different from 3 indicating isometric growth. The monthly mean Kn for the male and female were 1.041–1.125 and 1.009–1.236 respectively. The highest Kn value was recorded in July for both the sexes, which may be due to advance maturity stages. The present study will be useful in the context of biological management of mullet fishery as well as to find out aqua-farming potential of Tade gray mullet
Risking lives for living: a study on underwater fishing in the Padma River, Bangladesh
Get PDFoai:ojs2.journal.bdfish.org:article/1Different types of fishing methods and gears are being employed across the globe including Bangladesh. This study describes the underwater fishing method in the Padma River- one of the three largest rivers in Bangladesh. Standardised efforts have been made for collecting data of interest between September 2016 and May 2017. Two types of underwater fishing, with or without using oxygen cylinders, were recorded. Mean duration of fishing per effort was higher (by 382%) when fishermen used oxygen cylinders. Mean water depth of fishing sites was also higher when oxygen cylinders were used. Three species of finfish (Rita rita, Sperata seenghala and Labeo calbasu) and one freshwater prawn species (Macrobrachium dayanum) have been identified in the catch. The catch was dominated by M. dayanum in both fishing types (27 ± 9.3 [with oxygen] and 15 ± 5.2 [without oxygen]). However, all the number of caught fish species varied significantly among different sampling months in both fishing methods (P < 0.001) except L. calbasu in fishing with oxygen cylinder. A number of health issues of the fishermen were also recorded
Population structure and some growth properties of chub Squalius cephalus (Linnaeus, 1758) in Devres Stream of Kızılırmak River, Turkey
Get PDFThis study describes the population structure, growth and condition factor of chub (Squalius cephalus) in Devres Stream of Kızılırmak River caught between June 2010 and June 2011. S. cephalus individuals ranging between I and VI years old were caught from Devres Stream. Studied individuals were between I and VI years old and their sex was determined as 51.67% male and 48.33% female. The fork length and body weight ranged from 8.79 – 19.64 cm and 9.73 – 126.60 g respectively. The von Bertalanffy growth equations were found: Lt = 27.163 [1 – e–0.159 (t+1.47)] for females and Lt = 27.078[1 – e–0.160 (t+1.46)] for males; Wt = 286.14 [1 – e–0.159 (t+1.47)]3.1049 for females and Wt = 284.43 [1 – e–0.160 (t+1.46)]2.9692 for males. The condition factor was calculated as 1.432 and 1.378 for females and males respectively
Food and feeding behaviour of Mozambique tilapia (Oreochromis mossambicus Peters) from Borna Reservoir of Maharashtra, India
Get PDFThe food analysis of 80 specimens of Oreochromis mossambicus collected from Borna Reservoir of Maharashtra, India revealed that the food of juveniles mainly consisted of rotifers (35%), followed by copepods (30%), Chlorophyceae (20%), Bacillariophyceae (10%) and aquatic insects (5%). While the food items recorded in the gut of adults were Chlorophyceae (40%), followed by Bacillariophyceae (30%), rotifers (15%), copepods (10%) and aquatic insects (5%). During present study it was found that the juveniles of O. mossamobicus mainly feed on zooplankton, and adults on phytoplankton. Intense feeding was noticed during summer season and juveniles were the active feeders