11 research outputs found
Neem leaf juice as bio-safe anaesthetic against two live fish, Anabas testudineus and Channa punctata
No full textActivity of fresh neem leaf juice to immobilize, anaesthetize and fatal effect were studied against two live fish species, Anabas testudineus and Channa punctatus. The concentrations, 5, 10, 15 and 20% of neem leaf juice affected both the species, but A. testudineus was found to be comparatively more susceptible to the treatment than C. punctatus. The time required to immobilize were 4 to > 6 hours for A. testudineus and 7 to 9 hours for C. punctatus; to anaesthetize were 6 to > 12 hours and 8 to 10.15 hours for A. testudineus and C. punctatus respectively; and death occurred 7 to > 13 hours in A. testudineus and 9 to 10.45 hours in C. punctatus after treatment depending on the concentrations. The toxic effects were positively co-related with the concentrations and negatively co-related with the total weight of the fish, though the values of the coefficient of the correlations (r) were low. At the anaesthetic stage, the colour of skin, gills and eye were changed, the fishes showed irritated movement first (A. testudineus) and then became sluggish (both species), and instead of the normal fishy smell the fishes gave neem leaf like smell
Morphometric characters and condition factors of five freshwater fishes from Pagla river of Bangladesh
No full textThe research was aimed to carry out the length-length relationships, length-weight relationship and condition factor of five freshwater small indigenous fish species i.e. Amblypharyngodon mola, Puntius ticto, Cirrhinus reba, Chanda nama and Aspidoparia morar from the Pagla river Bangladesh. The relationships equations among different body length parameters of each species were found highly significant. The length-weight relationship equation were found as TW=0.0351 TL2.86 for A. mola, TW = 0.0104 TL3.10 for P. ticto, TW = 0.0261 TL2.96 for C. reba, TW = 0.0175 TL2.845 for C. nama TW= 0.0101 TL3.05 for A. morar. The “b” values ranged from 2.845-3.10 which remained on the expected range of optimum growth
Report on a heronry at the Rajshahi University Campus
No full textKey words: Heronry; cormorant; heron; egret; RU campus DOI: 10.3329/jles.v5i0.7358 J. Life Earth Sci., Vol. 5: 97-100, 2010</jats:p
The population growth of <i>macrobrachium lamarrei</i> (H M Edwards) on different conditions
No full textContext: Bottom condition and aquatic plants of the water bodies play important roles on the population growth of Macrobrachium lamarrei. Objective: To study the effects of different bottoms and aquatic vegetations on the population growth of Macrobrachium lamarei. Materials and Methods: Brood stocks of M. lamarrei were maintained in mini ponds, and they were fed in 24h with supplemental diets. For observing the effect of bottom condition on the prawn population three tanks (each 32"x36"x21"with a constant water depth of 16") were prepared: tank I, cemented bottom with no vegetation; tank II, muddy bottom and with water hyacinth and tank III, sandy-muddy bottom (2:1) with water hyacinth. To study the effect of aquatic plants on the population separate four tanks were prepared with sandy-muddy bottom (1:1) and subsequently with different vegetations. These were: tank I with Ipomea, tank II with Alternanthera, tank III with Eichornia, Ipomea, Alternanthera, Wolffia and Lemna, tank IV with Wolffia and Lemna. M. lamarrei of both sexes (N = 40-55) were released in each tank depending on the experimental type. Number of prawns of different stages was counted after 3 and 6 months to determine the effect of bottom condition, and after 3, 6 9 and 12 months to record the effect of aquatic plants. Results: M. lamarrei was found to prefer sandy-muddy bottom than cemented or muddy bottoms. The total population was recorded after six months as 760 (tank I), 1018 (tank II) and 1542 (tank III) where the initial number of released prawns was 55. Aquatic vegetations affected the population growthdifferently. After 12 months the total population was recorded as 2590 (tank I), 3416 (tank II), 1360 (tank III) and 1580 (tank IV). Population of M. lamarrei was maximum when Alternanthera (Santi sak) was present. Conclusion: The results provide baseline information for establishing culture system for M. lamarrei and related smaller species of this genus simultaneously. Keywords: Bottom condition; aquatic vegetation; population; Macrobrachium lamarrei. DOI: http://dx.doi.org/10.3329/jbs.v18i0.8777 JBS 2010; 18(0): 60-65</jats:p
Age-related response of <i>tribolium castaneum</i> (Herbst) larvae to diatomaceous earth at different exposure periods
No full textContext: Diatomaceous earth (DE) compounds have been recognized as reduced risk and eco-friendly compounds, which can be used in the insect pest management programmes for food storage and processing areas. Objective: To determine the repellent or attractant property of a DE formulation (Mitex) against the larvae of Tribolium castaneum (Herbst), a major pest of stored-products. Materials and Methods: The experiment was conducted in choice chambers, which was divided into two equal halves by drawing a line through the midline. One half of the chamber was loaded with untreated flour (control) and the other half was loaded with DE-treated flour. Twenty larvae of a definite age were released in the midline of the two foods, thus providing them an option for choosing either treated or untreated food. The experiment was set separately for different ages of larvae (9-, 12- and 15-day old), doses of DE (2, 4, 8, 16 and 32 mg DE/g of flour) and exposure periods (24-, 48-, 72-, 96- and 120-hours). All the experiments were replicated three times and conducted at 30 ± 1°C in an incubator without humidity and light control. Differences of the distribution of the larvae in treated and untreated flour was analyzed by χ2 test. Results: The efficacy of a diatomaceous earth (DE) compound (Mitex) as a repellent or an attractant was tested against 9-, 12- and 15-day old larvae of Tribolium castaneum (Herbst). Larvae of all ages were significantly (p<0.001) repelled by DE at doses from 8-32 mg/g food at all exposure periods of 24-, 48-, 72- 96 and 120 h. The mature larvae (15-day old) showed tolerance to the low doses like 2 and 4 mg/g food. Conclusion: The present results revealed that DE can be used as a reduced risk repellent compound in the grain and cereal stores, flour mills and grocery shops to manage the larval population of T. castaneum. Keywords: Age related response; T. castaneum; diatomaceous earth DOI: http://dx.doi.org/10.3329/jbs.v18i0.8773 JBS 2010; 18(0): 40-43</jats:p
“Women in an Alien Land”- Nuances of Diasporic Identity and Survival in Bharati Mukherjee’s Desirable Daughters
No full textBharati Mukherjee, an Indian Born, Canadian/ American novelist has made a deep impression on the literary canvass. The prime premise of her works is the issues encountered by women in the foreign atmosphere. As a diasporic author most of her characters are ‘displaced’ and ‘alienated’ from the land of origin to USA where they are ‘simultaneously invisible’ as an individual and ‘overexposed’ as a racial minority. Focusing on Mukherjee’s Desirable Daughters, first of the trilogy including The Tree Bride and Miss New India, the present paper attempts to analyze the complexities of diasporic identity and the process of re-birth and re-invention of Indian women immigrants to adapt in the new world. A story of three sisters- Padma, Parvati and Tara, the novel showcases the problems of identity of Indian immigrant women in an alien society as they suffer from ‘no greater visibility but great marginality’. The problem with these sisters is not only that are immigrants but what makes their condition worse is their gender as well. Being with the label of ‘second sex’, these women are often confronted by a double quest- quest for identity as a woman first and second as a displaced human being in an alien world. The diasporic situation in fact entangles the sisters into a maze- standing between two worlds-with complex realities of unequal cultural dynamics of the traditional homeland and liberal spaces of host land- they tend to experience conflicting subjectivities of freedom and subjugation, yet they do find a way for self-exploration and deliberation to conceive new identities and move beyond the fixed definitions of diasporic Indian women. So, my paper will be a modest attempt to unravel the nuances of diasporic identity which is always a matter of ‘becoming’ as well as of ‘being’ and to highlight the extremely individualistic ways of survival of the three immigrant sisters in an apparently alien culture
Effect of Steroid Hormone (Ecdysone) on the Pupal and Larval Developments of <i>Tribolium castaneum</i> (Herbst)
No full textEcdysone is a steroid hormone especially found in insects and mammals. One day old pupae of Tribolium castaneum were exposed to crude ecdysone at different concentrations of 10, 20, 40, 80, 160, and 320 μl/kg of whole wheat flour each for 1, 3 and 5 days. Adult recovery was significantly reduced in the treated pupae (F=3.47, P<0.01, df=7), and produced deformed individuals (F=39.29, P<0.001, df=7) at all exposure periods. The developmental time was similar in both the treated and untreated ones. The latent effect of the ecdysone treatment increased both the larval (F=4.26, P<0.001, df=7) and pupal (F=8.56, P<0.001, df=7) periods of the progeny reared on untreated foods. Similarly, the latent effect hampered recovery of the adult progeny (F=7.79, P<0.001, df=7) producing deformed individuals (F=2.65, P<0.05, df=7). Key words: Ecdysone; T. castaneum; Developmental period; Adult recovery. DOI: 10.3329/bjsir.v45i1.2213 Bangladesh J. Sci. Ind. Res. 45(1), 63-68, 2010</jats:p
