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Item Incidence of Bacterial and Viral Diseases of Silkworm, Bombyx Mori L. in Bangladesh and their Control(University of Rajshahi, 1989) Barman, Anil Chandra; Rahman, Mustafizur; Quayum, M. A.Like other forms of life, the silkworm, Bombyx mori L. is also affected by various types of diseases. During the growth the silkworms come in contact with a number of pathogenic agents like virus, bacteria, fungus, protozoans etc. under natural environmental conditions. Life functions are thus interfered and a disease occurs. The ultimate result is the loss of worms and hence loss of cocoon production. The earliest scientific report on insect diseases was on silkworm ailments (Kirby 1826). Afterwards it was experimentally demonstrated that the microorganisms are the causative agents for certain sickness in silkworms (Steinhaus 1963). A major breakthrough in our understanding of silkworm disease was achieved by Pasteur (1885) who identified that the protozoan, Nosema sp. was responsible for the devastating disease ' pebrine' of silkworm (Rene Dubas 1960). Bacterial and viral diseases of silkworm are the most common diseases inhabiting all the silk producing countries and areas, although their severity varies with the consequent interaction of existing environment of different regions. Total crop losses due to these diseases are rarely known, but the cocoon yield is largely hampered affecting national plan as well as personal income. In any of the cases of bacterial or viral diseases, starting point is the individual silkworm from which the disease is spread to the population. The occurrence of disease in a population is the consequence of interaction between pathogen, host and the environment……………………….Item Incidence of Bacterial and Viral diseases of silkworm. Bombyx mort l. In Bangladesh and their control(University of Rajshahi, 1989) Barman, Anil Chandra; Rahman, MustafizurLike other forms of life, the silkworm, Bombyx rnori L. is also affected by various ts of diseases. During the growth the silkworms come in contact with a number of pathcqenic agents like virus, bacteria, fungus, protozoans etc. under natural environmental conditions. Life functions are thus interfered and a disease occurs. The ultimate result is the forms and hence loss of cocoon production-. The earliest scientific report on insect diseases was on silkworm ailments ( Kirby 1826). Afterwards it was experimentally demonstrated that the micro- .__ organisms are the causative agents for certain sickness in silkworms (Steinhaus 1963). A major breackthrough in our undestanding of silkworm disease was achieved by Pasteur (1885) who identified that the protozoan, Nosema sp. was responsible for the devastating disease ' pebrine' of silkworm (Rene Dubas 1960). Bacterial and viral diseases of silkworm are the most comnon diseases inhabiting all the silk prooucing countries and areas, although their severity varies with the ccnsequent interaction of existing env- ronment of different regions. Total crop losses due to these diseases are rarely known, but the cocoon yield is l;:irgely hampered affecting national plan as well as personal income. In any of the cases of bacterial or viral diseases, starting point is the individual silkworm from which the disease is spread to the pop..ilation. The occur1ence of disease in a p-,pulation is the con r---. since of interaction between pathcqen, host and the environment. -----------Item Epidemiological Investigation of Schistosomosis in Domestic Cattle in Bangladesh(University of Rajshahi, 2013) Begum, Nurjahan; Mannan, Md. Abdul; Awal, Md. AbdulBovine schistosomiasis is a disease of great economic importance in cattle production resulted from infection by helminth parasite of the genus Schistosoma. An epidemiological study of bovine schistosomiasis was conducted in Mymensingh, Netrokona, Kishorgonj, Chittagong and Sirajgonj areas of Bangladesh. On farm and abattoir survey were done to find out the risk factors associated with epidemiology, abundance of vectors and their relationship with temperature and rainfall during September 2009 to August 2011. Epidemiological data were collected from five different agro-ecological zones and schistosomiasis was found as one of the major bovine parasitic diseases. Among the different areas Sirajgonj district, male, adult animal and rainy and summer seasons were identified as significant risk factors for bovine schistosomiasis by egg (egg per gram of feces) count in Bangladesh. Among the three species of mostly common schistosomes in Indian sub-continent two species of were recorded during this period. Schistosoma indicum (29.9%) were the most common species than Schistosoma Spindale (10.6 %). Based on fecal egg examination a significant variation in the prevalence of bovine schistosomiasis were observed according to districts, ages, breeds, sexes, physical conditions, fecal consistency, sanitations, grazing, diets, de-worming, farming systems and seasons. Mesenteric blood vessels examination showed higher prevalence (48.0%) than fecal examination (33.2%). A significant variation in the prevalence of bovine schistosomiasis was observed according to regions and seasons. The highest number of total schistosomes counted from one mesenteric blood vessel was 322 and lowest was 18. In the study of intensity 27.4% of the mesenteric blood vessels showed moderate intensity (21-100 pair) which were statistically significant than low and heavy worm intensity. In order to find out the role of vector host snails were examined and 3.8% were found positive for cercariae of schistosomes of cattle with seasonal variation. Among the three different types of snails Indoplanorbis exustus played the dominant role followed by Lymnaea luteola and L. auricularia for shedding of Furcocercus cercariae. The shedding of Schistosoma spp. carcariae was significantly higher (P<0.01) during rainy season. The miracidial hatchability study clearly showed that miracidia hatching increases with the decreasing age of cattle. This observation clearly indicates that young animal plays an important role in the transmission cycle. Though clinical signs were not observed but histopathology of liver, small intestine and large intestine showed slight to moderate parasitic granulomas produced by the S. indicum eggs and adult parasites. Two simple methods such as egg detection method and miracidia hatching test was of great help in performing a proper diagnosis and fair assessment of schistosomiasis in the field. It may be concluded that schistosomiasis in cattle could be listed among the infectious diseases with special care because of climate change in the future which will severely affect the disease transmission dynamics. This study indicated that treatment of the infected animal with proper anthelmintic at the end of summer and restrict their movement nearer to water reservoirs could reduce the infection rate to a greater extent.Item Ecological Characterization of Indigenous Rhizobium Populations in Rajshahi Area(University of Rajshahi, 2016) Nushair, Ali Mohammad; Saha, Ananda Kumar; Rahman, Md. AnisurRhizobium spp. were isolated from root nodules of Green Gram, Black Gram, Lentil, Pigeon Pea, Sweet Pea, Chick Pea, Cow Pea and Bean on Yeast Extract Mannitol Agar (YEMA) and their morphological, cultural, physiological and biochemical characteristics were studied. It was observed that the colonies were circular, light pink, convex, entire and opaque. The bacterium was gram negative, rod shaped, aerobic, non-spore forming and motile. In this study, all isolates were showed hazy appearance in the motility media and also were positive for Catalase, Citrate Utilization Test, Urea Hydrolysis, Congo red test, Nitrification test, Oxidase Test, Triple Sugar Iron Test , Mac Conkey Agar Test and, motility Tests. The samples were found negative for Methyl Red (MR), Voges-Proskauer (VP), Indole, Starch hydrolysis test, Hydrogen Sulphide production and Hofer’s alkaline test. Utilization of different carbon sources is an effective tool to characterize the isolates. In the present study sucrose, fructose, galactose, maltose and mannitol (25 mg Hi-media, India) and 20% solution of glucose, lactose, arabinose and xylose were utilized for this test. All the isolates tested here can ferment sucrose, glucose, fructose, mannitol and produce acid. These carbon sources are generally utilized by bacteria of the genus Rhizohium. Fast growing Rhizobial strains utilized a wider variety of carbohydrates than the slow growing strains. Their ability to metabolize a broad range of carbon substrates may be advantageous for survival in soil. Isolates which were named as Lentil, Cow Pea and Bean can be utilized in all the nine sugar and the produced acid. Green Gram, Black Gram, Pigeon Pea, Sweet Pea, Chick Pea cannot ferment maltose sugar. Besides this isolates from Green gram, Black Gram, Pigeon Pea Sweet Pea and Chick Pea fermented all sugar but Green gram and Black Gram cannot fermented galactose, lactose, arabinose and xylose. Resistance patterns of the isolates to thirteen antibiotics were studied. Screening for antibiotic resistance in our study revealed that most of the strains were resistant to Ampicilin, Erythromycin, Gentamicin, Amoxycillin, Penicillin, Streptomycin and Nalidixic acid. The generalized sensitivity to Mecillinam, Ciprofloxacin, Cotrimoxazole, Pefloxacin, Ceftazidime and Tetracycline were found in our study. An optimum growth was observed at room temperature (28ºC to 30ºC). The organisms were found to be temperature sensitive as at higher and lower temperatures, a low growth was observed that might be due to a hindrance in the metabolic activity. pH is an important parameter for the growth of the organism. Best growth of Rhizobium was reported at pH i.e. 7 and very less growth was observed in the medium with pH 5.0 and 9.0. Salt stress may decrease the efficiency of the Rhizobium-legume symbiosis by reducing plant growth and photosynthesis, and hence nitrogen demand, by decreasing survival and proliferation of rhizobia in the soil and rhizosphere, or by inhibiting very early symbiotic events, such as chemotaxis and root hair colonization, thus directly interfering with root nodule function. The experiments also showed that the cells were able to grow in 1% NaCl containing medium but unable to grow on higher concentration, showing that the isolate was sensitive to the salt concentration. In general, the phenotypic study isolates showed large physiological and biochemical biodiversity. Indeed, the studied strains showed a variable resistance against stress factors, temperature, pH, salinity, resistance to antibiotics and heavy metals, which allowed the selection of good candidates for genetic studies. Several investigators have studied the genetic diversity of Rhizobium isolated from several countries around the world. However, it needs I6S rDNA sequencing experiment for further identification of the phenotypic species. These experiments will help to know the relationship between the phenotypic and genotypic identification as well as the phylogenetic position of the identified isolates. 16S rRNA sequencing has helped the description of Rhizobium spp. In the studies reported here, the genetic biodiversity of eight represented strains were examined. The genetic study carried out is a quick method that gives a better idea of the diversity of these strains. The 16S rDNA was sequenced to determine the taxonomic position of these strains, and the results revealed that there was a great genetic diversity among the eight rhizobial strains studied. Indeed, sequence analysis of 16S rDNA and subsequent BLASTn analyses indicated that six strains had 95 to 98% and other two bellow similarity with Rhizobium spp. The phylogenetic distances indicate that the relationships among this group and the Agrobacterium species are as distant as those among the genera Mesorhizobium and Sinorhizobium. This clearly showed that subgroup belonged phylogenetically to the genus Rhizobium. Although the phylogenetic position of subgroup was not found to be distinct from that of other Rhizobium sp. by analysis of the partial 16s rRNA sequences. It was distinguished clearly from the Rhizobium sp. CCNWYC119, Rhizobium sp. CCNWYC119, Rhizobium sp. SOY12, Rhizobium sp. CCNWYC119, Rhizobium sp. CCNWYC119, Rhizobium sp. CCNWYC119, Rhizobium sp. SOY7, Rhizobium sp. SOY12 position by the full sequence of its 16S rRNA genes. So it seems that the partial sequencing of 16S rDNA has limited value in determining phylogenetic relationships among rhizobial species. The BLASTn search results for the partial sequences of the 16S rRNA gene of the isolates revealed that the purity and concentration of extracted DNA were performed at 260/280 nm obtained as 1.77 for Green Gram, 1.74 for Black Gram, 1.74 for Lentil 1.77 for Pigeon Pea,1.85 for Sweet Pea,1.77 for chickPea,1.82 for Cow Pea and 1.84 for Bean and concentration as 42.0, 83.9, 28.9, 49.0, 88.5, 68.8, 86.8 and 69.7 ng/µl for Green Gram , Black Gram, lentil, Pigeon Pea Sweet Pea, Chick Pea, Cow Pea and Bean, respectively. Finally the selected eight bacterial isolates were identified up to species as Rhizobium sp. through 16S rDNA gene sequencing. There were eight experimental plants from which eight colonies of Rhizobium were isolated of which five strains showed similarity among them (Rhizobium sp. CCNWYC119 ) another two strains were also similar (Rhizobium sp. SOY12 ) and only one(Rhizobium sp. SOY7 ) was different based on the nucleotide sequence. The 16S rDNA sequence reveals that the isolated strains Green Gram , Black Gram, Lentil, Pigeon Pea Sweet Pea, Chick Pea, Cow Pea and Bean are homologous to bacterial strain Rhizobium sp.CCNWYC119, Rhizobium sp.CCNWYC119, Rhizobium sp.SOY12, Rhizobium sp.CCNWYC119, Rhizobium sp.CCNWYC119, Rhizobium sp. CCNWYC119, Rhizobium sp. SOY7, Rhizobium sp. SOY12 respectively. Also the results obtained in this study show some interesting aspects on the growth effects of Rhizobium inoculation in Green Gram, Black Gram, Lentil, Pigeon Pea Sweet Pea, Chick Pea, Cow Pea and Bean which was grown in pots under controlled environment. The results indicate the successful nature of usage of commercial inoculants of Rhizobia to improve the growth effects of the pulses studied. Successful results by using commercial inocula of Rhizobia were obtained in field grown eight isolates ( Green Gram , Black Gram, Lentil, Pigeon Pea Sweet Pea, Chick Pea, Cow Pea and Bean) showed significant difference between inoculated and control. The no of nodule, fresh weight of nodule, dry weight of nodule, plant height, pod weight and seed weight were taken. Rhizobial inoculation induced significant changes in plant growth characteristics. This study also showed that enhancement of soil fertility along with the yield of legume plants occurred due to nodulation. Soil treated with Rhizobium spp. showed higher values than control regarding total nitrogen and organic matter (%).Item Epidemiology and Control of Mange on Goat in Rajshahi District(University of Rajshahi, 2014) Rahman, Shaziea; Das, Bidhan Chandra; Wall, RichardThe parasitism is an important limiting factor to rear goats in Bangladesh as the climatic condition of the country favors the development and survival of various parasites. In parasitic problems, mange infestation is common in goats which directly or indirectly reduce their health and productivity. The objectives of this study are to determine the prevalence of mange mite on goat, assess the risk factors and health of goat in Rajshahi in relation to mange infestation and evaluate the economic impact of mange and to find out the alternative measures of mange control especially with herbal products. The study was carried out through questionnaire survey, clinical examination and the experiment of mange control in goats in the study areas of five Upazila namely Boalia, Puthia, Poba, Gudagari and Baghmara of Rajshahi district. In the prevalence study, the relevant data were collected from randomly selected a total of 129 goat rearing farms which consists a total of 1277 goats during the period from July’2010 to June’2011. In the experimental study of mange control, fifteen affected goats of both sexes aged between 10 and 30 months which were divided into five groups randomly and 3 goats were considered in each group. The treatments were considered with control (A), Neem ointment (B), Ata ointment (C), Mehedi ointment (D) and Ivermectin (E). The control experiment was conducted during November’2012 to December’2012. The collected experimental data were analyzed using SPSS Version-15. Association between prevalence and explanatory variables was found using chi-squire (P) test. A descriptive statistical analysis and ANOVA were used for the results of clinical parameters (skin lesion and bodyweight), certain hematological parameters (Hb, TEC, PCV and TLC) and biochemical parameters (SGOT and SGPT). The significant difference was set as (P<0.05) and (P<0.10) in the prevalence and experimental study, respectively in the analyses. The overall prevalence of mange mite was 5.95 per cent in goats in the study. The highest and the lowest percentages of mange mite prevalence were observed in large farm (9.04%) and small farm (4.13%), poor feeding (8.25%) and good feeding (3.61%), Black Bengal (6.93%) and crossbreed (3.09%), age 3 years and above (8.47%) and age below 01 year (3.60%), female (6.78%) and male (3.87%), winter season (10.74%) and summer season (2.09%), low land (8.81%) and high land (3.09%), conventional housing system (6.51%) and semi-intensive housing system (2.34%), poor housing condition (8.97%) and good housing condition (3.50%), poor health condition (25.32%) and good health condition (2.03%), temperature below 210C (8.47%) and temperature 290C & above (2.76%), rainfall below 50 mm (8.24%) and 50 mm to < 200 mm (3.73%) and humidity below 65% (8.93%) and humidity 65% to < 85% (3.64%), respectively and the prevalence of mange mite was significantly different in each risk factor (P<0.05). The mange mites were the highest frequency on the head region and the lowest were on tail, leg and whole body. The maximum economic loss was incurred in large farm and it was the lowest in small farm. Only one species Sarcoptes scabiei was identified through the preparation of permanent slide. The recovery of skin lesion was statistically significant (P<0.10) in all treatment groups except control group (P>0.10). The bodyweight was increased in all treatment groups and it was decreased in control group which was significant (P>0.10). After treatment, Total Erythrocytes Count (TEC million/ cu.mm), Hemoglobin content (Hb gm %), Packed Cell Volume (PCV %) and Total Leukocytes Count (TLC thousand/ cu.mm) of blood was increased in all treatment groups except control group which were significant (P<0.10) and the SGOT and SGPT of blood were decreased in all treatment groups except control group which were significant (P<0.10). From the prevalence study, it may be concluded that this study quantifies the level of mange mite infestation in goats corresponding to the different risk factors which demands immediate control program and more epidemiological study for detail information of the constraints of goat health and production. In the herbal ointments, Neem (Azadirachta indica) was more effective for control of mange in goats than Mehidi (Lawsonia inermis) and Ata (Annona reticulata). The patent drug Ivermectin was very much successful in mange mite infestation than the herbal ointments. Further studies are required to clarify the efficacy of the ethnoveterinary and anthelmintics widely used in agro ecologies, animal species and livestock management system in Bangladesh.