http://rulrepository.ru.ac.bd/handle/123456789/55 2026-04-07T21:43:52Z http://rulrepository.ru.ac.bd/handle/123456789/1140 Fish and Fishery of Aspidoparia (Cypriniformes: Cyprinidae) of the River Padma Sultana, Nasrin Bangladesh has vast fishery resources. The inland water areas of the country comprises 1.03 million hectares of rivers, canals and estuaries; 1,14,161 hectares of natural depressions such as the beals' and 'haors'; 1,61,943 hectares of ponds and tanks, 5,488 hectares of ox-bows; 68,800 hectares of Karnafuli reservior; 2.8 million hectares of flood plains and 87,300 hectares of brackish water aquaforms (Rahman, 1989). A total of 260 species of indigenous species of fin fishes are found in the freshwater habitats of Bangladesh and majority of these fishes are small sized (Rahman, 1989). The small indigenous fishes (SIS) form an important human food item, rich source of complete proteins containing all the essential aminoacids in right proportion. Fish protein is said to be more healthier and cholesterol free and also contains fatty acid which help in cholesterol absorption in the body tissues. The people are advised to take much smaller fish than meat. According to FAO report, (1991), fish contain 72% water, 19% protein, 89% fat, 0.15% calcium 0.25% phosphorus and 0.10% vitamin A,B,C and D. National Household Expenditure Survey (NHES) shows that anmel fish consumption in Bangladesh peaked in 1985 at 13.2 kg/person, had declined to 12.6 kg/person by 1992. This is in the same agreement with the information developed by North West Area Development Study (NWADS), which shows that overall fish supply has stagnated, resulting in price increase in real terms of over 2.8% per annum in the Northwest Region (Interim Report Vol-5 ADB February, 1997). The SIS fishes thus, make a very significant contribution to the daily intake of fish. Moreover, Siddiqui (1985) reported that in Bangladesh about 80 percent of the population is poor and they mainly depend on small size fish for their daily supply of animal protein at a reasonable price. Another advantages of small size fish is that they could easily breed and grow in water bodies, where culture of other major fishes are impossible. However, the ever expanding programme of flood control, drainage and irrigation is interfering with the whole ecological system in fishery resources, thereby causing both loss and degradation of their habitats. Which will inevitably lead to diminution and even disappearance of 95 percent of inland fish production. The present species 4. morer is mostly available in the river systems of Bangladesh. The biology of this species had been reported by Sultana (1991), Bhuiyan et al. (1992) compared the past and present data on the landing of the species together with the market price found that the natural production of the species is decreasing due to construction of the Farakka Barrage and oder FCD projects which caused detremental effect on the national aquatic system. Moreover, over exploitation of fish population and indiscriminate use of agrochemicals also adversely affected the fisheries resources. A. morar is an important species due to its high nutritional value in terms of protein content. Inspite of its usefulness as a source of protein, no detailed studies on the chemical and biochemical investigation has so far been reported. This is a small sized fish with a maximum size of 145 man, feiches the hightest market price due to its taste and flavour. This fish generally live in shallow water of the sandy bottom and medium current areas of the rivers. We hope the present finding may help to increase its population in the river Padma near Rajshahi This Thesis is Submitted to the Department of Zoology, University of Rajshahi, Rajshahi, Bangladesh for The Degree of Doctor of Philosophy (PhD) 1997-11-01T00:00:00Z http://rulrepository.ru.ac.bd/handle/123456789/1138 Effects of Agro Chemicals on Live Fishes Yasmin, Khaleda The effect of three organophosphorous insecticides, namely, diazinon 60 E.C., nogos 100 E.C. and dimecron 100 SCW on H. fossilis and three species of live A. testudineus, C. batrachus, were studied. The insecticides were in the form of emulsifiable concentrates. In bioassays the or toxicity tests, fishes were exposed to a series of concentrations of chemicals at the laboratory temperature. The dosages were 1.0, 2.25, 3.2, 5.6 and 10.0 ppm. Histopathological effects of these three insecticides on the same species were observed. The dosages were 2.25, 3.50, 5.0. 10.0 and 20.0 ppm respectively. The histopathology of the organs of normal fishes were done to compare them with those of the experimental ones. These insecticides induced certain cellular changes in different organs such as liver intestine, ovary etc. on these fishes. From the bioassay tests and histopathological studies, it was observed that diazinon was most toxic, nogos was moderately toxic and dimecron was least toxic to these fishes among the three insecticides. This Thesis is Submitted to the Department of Zoology, University of Rajshahi, Rajshahi, Bangladesh for The Degree of Master of Philosophy (MPhil). 1995-06-01T00:00:00Z http://rulrepository.ru.ac.bd/handle/123456789/994 Ecology, Biology and Fishery of Clupisoma Atherinoides (Bloch) (Cypriniformes:Schilbeidae)Ecology, Biology and Fishery of Clupisoma Atherinoides (Bloch) (Cypriniformes:Schilbeidae) Begum, Mahbuba The juvenile and adult of C. atherinoides is mainly a carnivorous fish. Its food consists mainly of crustaceans, insects, rotifers, protozoans, algae, debris and detritus. The juvenile and adult C. atherinoides are surface feeders. Monthly variations in the percentage composition of the food items in the different stages of the fish were recorded. The fish changed its food and feeding habit seasonally. The feeding intensity was very poor in mature fishes during the spawning period. The immature fishes fed actively throughout the year. The ratio of the total length and alimentary canal length of the juvenile and adult stages of the fish is I :0.56 and 1: O. 61 and it has a shortened alimentary tract. The relationships between the total length and alimentary canal length of the juvenile and adult showed strong linear relationship. The ovaries of C. atherinoides were classified into ten stages. Immature stage, maturing-I ( early developing), maturing-II (late developing), mature, ripe, pre-spawning, spawning, post spawning, spent and resting stage.---- This Thesis is Submitted to the Department of Zoology , University of Rajshahi, Rajshahi, Bangladesh for The Degree of Doctor of Philosophy (PhD) 1999-01-01T00:00:00Z http://rulrepository.ru.ac.bd/handle/123456789/984 Studies on The Optimum Population Density of Carps Fry In Nursery Ponds Afroze., Shelina The present work is on the optimum population density of three major carps fry viz. Labeo rohita,Catla catla and Cirrhina 􀀐rigal􀀒 in nursery ponds and tanks. A comperative study has been carried out on the growth rate of the fish fry on an exact time after releasing them in different nur­sery ponds and tanks at different ratios. Chapter I: Growth effeC!-l.-􀀖2􀀗􀀘rative study on Eh􀀜ic.2..= chemical factor and morphometric relati,£!:!sh1J22!ith different density. The total length/standard length and total length/ body depth relationships ha􀀢e been calculated in the linear regression equation for the three species of carp fry reared in tanks and ponds for initial and final measurements. It may be observed that SL and ED always depend upon TL ofthe species and positively correlated and the values were significant in all the cases. ------ This Thesis is Submitted to the Department of Zoology, University of Rajshahi, Rajshahi, Bangladesh for The Degree of Master of Philosophy (MPhil) 1990-01-01T00:00:00Z