Faculty of Veterinary and Animal Sciences

Incidence of Gastro-Intestinal Nematodes of Cattle in Rajshahi and Anthelmintic Efficacy of Medicinal Plants and Patent Drugs against Them

2022-06-23T06:44:55Z

Incidence of Gastro-Intestinal Nematodes of Cattle in Rajshahi and Anthelmintic Efficacy of Medicinal Plants and Patent Drugs against Them Sultana, Mst. Rokeya The experiment was performed in the Department of Animal Husbandry & Veterinary Science, Faculty of Agriculture and University of Rajshahi in collaboration with the Department of Pharmacology, Physiology, and Parasitology, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh. The prevalence of gastro-intestinal nematodes was observed in 400 randomly selected cattle during the period from June, 2011 to May, 2012 in greater Rajshahi in Bangladesh. The prevalence of Ascaris sp., Strongyles (Haemonchus sp., Trichostrongylus sp., Oesophagostomum sp. and Mecistocirrus sp.), Bunostomum sp., Trichuris sp. Strongyloides sp. and mixed infection were 6.5%, 25.5%, 2.25%, 5% 5% and 10.5%, respectively. The seasonal prevalence of gastro-intestinal nematodes was significantly highest in rainy seasons (June-August) 79.8% followed by autumn (September- November) 57.7%, summer (March-May) 44.3% and winter seasons (December-February) 34.8%. The incidence of gastro-intestinal nematodes was highest in Rajshahi district followed by Natore district, Naogaon district and Chapai Nawabgonj district and the intradistrict prevalence of gastro-intestinal nematodes in cattle was ranged from 38-62.5%. The incidence of gastro-intestinal nematodes in cattle was highest134 (67.0%) in 12 to <24 months old cattle and lowest 22 (36.7%) in 1 to < 6 months old cattle and highest incidence was also observed in female. The incidence of gastro-intestinal nematodes was more in cross breed than local breed. The incidence of gastro-intestinal nematodes was highest in L×F genotype followed by in L×F×SL genotype, L×SL genotype and local breed. The incidence of gastro-intestinal nematodes was highest in the month of July. Screening of 10 indigenous medicinal plants (Neem, custard apple, papaya, garlic, bitter gourd, jute, chaste tree, pineapple, pomegranate and betel leaf) of Bangladesh having reported anthelmintic activity and to determine the comparative efficacy in-vitro. Within these 10 plants, 3 showed 100%, 2 showed 90% and others showed 60-70% efficacy in water extract at the concentration of 100 mg/ml against adult worms. On the other hand, 5 showed 100% efficacy, 3 showed 90% and others showed 80% efficacy in ethanol extract at the concentration of 100 mg/ml among these 10 plants against adult worms. Ethanol extracts were more effective than water extracts against adult worms. Among 10 tested plants 2 medicinal plants (neem and korolla) and 2 patent drugs (Ivertin® and Levavet® were administered against gastro-intestinal nematodes in cattle for in vivo trail. Twenty five (25) naturally parasitized female cattle of Binodpur, Rajshahi, were selected for efficacy study of 2 indigenous medicinal plants and 2 patent drugs in-vivo. The animals were divided into five (5) groups (A, B, C, D, and E), each group consisting of five (5) cattle. Ethanol extract of leaves of neem @100 mg/kg b. wt and bitter gourd @100 mg/kg b. wt were administered orally to the cattle of group B and C respectively. Cattle of group D and E were treated with ivermectin (Ivertin®) @ 0.2 mg/kg body weight pour on and levamisole (Levavet®) @ 7.5 mg/kg b. wt. respectively. Cattle of group A was kept as infected control group. Prior to trials (day 0), initial body weight, total egg count of gastro-intestinal nematodes, biochemical, hematological and clinical parameters were examined and recorded. During the experimental period, faecal samples were examined on 7th, 14th, 21st and 28th day. Clinical (body weight), haematological (TEC, Hb, PCV, TLC, DLC, MCV, MCHC and MCH) and biochemical parameters (ALT and AST) were also observed on 7th, 14th, 21st and 28th day for the determination of effects of neem, bitter gourd, Ivertin® and Levavet®. In-vivo neem showed highest egg reduction among tested plants and ivermectin pour on showed 100% egg reduction. Anthelmintic treatment showed increased values than control for the TEC, Hb, PCV, neutrophil count of DLC, MCHC and MCH, decreased values for TLC and eosinophil count of DLC, very little changed values for monocyte count and lymphocyte count of DLC and no change was found in ALT and AST in cattle. G.I. nematodiasis is a great problem in Bangladesh especially in greater Rajshahi and the data generated from this study revealed that Ivermectin is drug of choice, levamisole is a good drug and as an alternative, farmers could use neem and bitter gourd with good therapeutic value. This thesis is Submitted to Department of Veterinary and Animal Sciences, University of Rajshahi, Rajshahi, Bangladesh for The Degree of Doctor of Philosophy (PhD)

Clinical Trends of Reproductive Disorders of Cows in Rajshahi District of Bangladesh

2022-05-06T08:03:04Z

Clinical Trends of Reproductive Disorders of Cows in Rajshahi District of Bangladesh Khaton, Rashida The aim of the present study was to evaluate the “Clinical trends of reproductive disorders of cows in Rajshahi district of Bangladesh.” The whole study was divided into three experiments to achieve the goal very successfully. Experiment I: Study on reproductive trends of dairy cows in Rajshahi district The present study was carried out from 6 upazilas and 4 metro thanas at Rajshahi district to evaluate the Clinical trends (reproductive performance and disorders) of dairy cows. A total of 500 cows selected and data were collected directly from the dairy farms owner by using questionnaires and diagnosis of reproductive disorders (RD) was made on the basis of history, clinical signs and response to treatment from July 2013 to June 2014. The average reproductive performance (RP) were recorded as age at puberty (AP) 26.42±0.22 m, age at first calving (AFC) 35.48±0.22 m, postpartum heat period (PPHP) 121.85±3.48 days, service per conception (S/C) 1.93±0.04, days open (DO) 136.80±3.57 days and calving interval (CI) 401.04±3.94 days. The better RP was found at Boalia and Rajpara thana but poor performance at Godagari upazila. Genotype had significant effect (P<0.05) on all the reproductive traits (RT) except on S/C. Local (L) × Holstein Friesian (HF) genotype showed earlier AP and AFC than L× Sahiwal (SL) and L. Age group had significant (P<0.05) effect on AP, AFC and other parameters were not significant (P>0.05). Middle age groups of cows had shown better RP than others groups. Parities of cows had significant effect (P<0.05) on PPHP, S/C, DO except on AP, AFC and CI. Third parity had better RP than others. The best RP was found in >300 kg BW groups. Body condition score had significant effect (P<0.05) on all RP. Good body condition score (BCS) had excellent RP. Secondary educational status of farmers had obtained better RP. Farming experience, rearing system and geographical location of farm had no significant effect (P>0.05) on RP. Farm size had significant effect (P<0.05) on all RT except on S/C and DO. The best RP was found in small size farm, concrete type of floor, good ventilation system, good quality of feed, preventive measure by veterinarian and AI breeding method. The overall prevalence of productive and RD was 78.6%. It was recorded, among the reproductive and productive diseases, abortion 13.4%, retained placenta 10.2%, dystocia 5.4%, vaginal prolapse 2.4%, uterine prolapse 1.4%, metritis 1.6%, pyometra 1.8%, still birth 0.8%, anoestrus 24.6%, repeat breeding 11.4%, mastitis 4.4% and milk fever 1.2%. The highest occurrence of RD was recorded in Tanore upazila (9.2%) and the lowest in Poba upazila (6.2%). Between the upazila and metro thanas the minimum occurrence of RD were recorded in metro thanas (31%) than upazilas (47.6%). The cross-bred cows were found more susceptible to RD (60.6%) than Local (18%). Maximum RD were observed in L×HF (37.2%) than L (18%). The highest prevalence of RD was observed in >9 years age groups of cows. The highest RD were observed in 2nd parity of cows. 200 to <300 kg body weight had shown the highest RDs than others. Good body condition score (BCS) had the lowest chance of RD than others. Secondary educational status of farmers had the lowest occurrence (16.4%) of RD than other group. The lowest (15.2%) RD was observed in vast farming experience (>5 yrs). The lowest prevalence of RD was found in grazing on pasture land (12.6%) and higher RD in intensive rearing system (39.8%). The small size farm was found minimum chance (20.6%) to RDs than others groups. The minimum no. of cows suffering from RDs in semi-urban (23%) than others. Less change of RDs in cows by natural service (19%) than artificial insemination (59.6%). Experiment-II: Study on biometrical measurement of reproductive organs in cows at study area A biometrical study of female reproductive organs of 100 dairy cows of different genotypes (Local, Local × Holstein Friesian, Local × Jersey and Local × Sahiwal), age (<3, 3 to ≤5, >5 years) and body weight (<200, 200 to <300, >300 kg) groups and different parities were conducted to measure reproductive organs. Reproductive organs (RO) of cows were collected immediately after slaughter from different slaughter houses in Rajshahi City Corporation (RCC) area. The mean length of vulva, vagina, cervix and body of uterus were recorded as 8.85±0.14 cm, 22.59±0.34 cm, 5.02±0.11 cm and 3.12±0.72 cm, respectively and corresponding values for the width were 4.83±0.13 cm, 5.44±0.16 cm, 4.56±0.12 cm and 2.51±0.59 cm, respectively. The mean length of right uterine horn and oviduct were 25.34±0.72 cm and 21.05±0.39 cm and that of left one were 25.79±0.73 cm and 21.00±0.38 cm, respectively. Local × Holstein Friesian had significantly higher values (P<0.05) on the most of parameters (Length, width, thickness and weight) of genitalia measured, followed by the Local × Jersey, Local × Sahiwal and Local. L×HF had recorded the longest uterine horn (29.20 ± 1.65 cm for right and 29.87 ± 1.75 cm for left), uterine body (3.42±0.20 cm length and 2.83±1.40 cm width), cervix (5.64±0.24 cm length and 4.89±0.23 cm width) and vagina (24.66±0.64 cm length and 6.08±0.36 cm width) than other genotype. Age group >5 years and BW groups >300 kg and 3rd parity had significantly (P<0.05) higher values on most of the parameters measured than other age groups, BW groups and parities, respectively. All biometrical measurements of RO were increased with the advancement of age and body weight indicated the effect of age and body weight of cows. The right ovary was wider in diameter, larger in length and heavier in weight than left one in all genotypes, age and body weight groups. This confirms the fact of right ovary being more active than the left one. In conclusion, the biometry of reproductive organs in L × HF and L × J and age group (3 to ≤ 5 and >5 years) and body weight group (200 to <300 and >300 kg) of dairy cows are suggestive for selection to get maximum benefits from crossbreeding in respect of productive and RP for livestock improvement and also for genetic improvement. Experiment-III: Study on the gross and histopathological changes of the affected organs A study was conducted to determine the pathological diseases (PD) in the reproductive system of cows. A total of 115 female genital organs were randomly collected during the period from March, 2014 to June, 2015 from eight (8) slaughter houses of Rajshahi district. All samples were collected from the cows irrespective of ages. Among these samples, 73% samples showed gross and histopathological changes. The result showed that pathological conditions recorded grossly in the reproductive system were granular vulvo-vaginitis (9.57%), swollen and edematous cervix (10.43%), endometritis (19.14%), pyometra (5.21%), mucometra (2.61%), parasitic cyst within the uterus (0.87%), follicular cyst (9.57%), luteal cyst (2.61%), multicystic ovary (1.73%), mesovarian cyst (0.87%), sub-active ovary (3.48%) and hemorrhage in ovary (6.96%). The representative samples were preserved in 10% buffered neutral formalin for histopathological examination. The relative incidences of various histopathological disorders were endometritis (30.36%), cervicitis (21.42%), vaginitis (23.21%), follicular cyst (17.87%) and multicystic ovary (7.14%). It is concluded that more than one disorder were existed in all sample. These disorders in the female genital organ of cows would enable us to design future research and hygienic care at breeding and parturition should be into consideration and also support to manage the different fertility related problems in cows. Finally, it was concluded that monitoring of the reproductive health status of cows is helpful for making decision about treatment or culling of non-productive cows from the herd and also selection of good quality of dairy cows for increase calf and milk production which will be helpful to overcome losses due to reproductive disorders. This thesis is Submitted to the Department of Veterinary and Animal Sciences, University of Rajshahi, Rajshahi, Bangladesh for The Degree of Doctor of Philosophy (PhD)

Intervention of Bio-Security in Broiler Farming of Bangladesh

2022-05-06T06:07:01Z

Intervention of Bio-Security in Broiler Farming of Bangladesh Ali, Mohd. Younus The purpose of the study was to determine the productive performances & profitability and meat quality of broiler farming carried out with and without bio-security management interventions during winter and summer in different locations of Bangladesh. In the first step, a survey study was carried out to assess the broiler production performances reared in different locations; Pabna, Rajshahi and Kishorgonj having 30 broiler farmers in each. Data were collected from a total of 90 broiler farmers by direct interviewing using a semi-structured questionnaire during January 13 to June 2014. Socio-economic conditions of small & medium scale broiler farmers were considered, the factors influencing profitability were analyzed and constraints to broiler farming at rural households were identified. Data were edited and categorized as per farm sizes, such as 23% farmers of 500 broilers, 20% of 600, 16% of 700, 17% of 800, 14% of 900 and 11% farmers of 1000 broilers. The data were processed using mean, percentage and master tabulation sheet. Regression models were used to determine the relationship between some socio economic factors and broiler production performances considering net return. Broiler production performances were positively related with education, farm size, training, land size and age of the farmers and significant differences of education & farm size (P<0.01), training & land size (P<0.05) and age (P<0.001) were found. On the other hand, in case of farmer’s annual income had no significant relationship with the broiler performance. In terms of production performance, feed conversion efficiency was improved trends with an increasing in the size of the farms and significant difference (P<0.01) was found among the farm sizes. The study also focuses on broiler production constraints and production systems for the improvement of broilers farming in Bangladesh. Lacking of quality chicks was the major constraint appeared to be a common complaint to the farmers. Fluctuating price of chicks & marketable live broiler, low price of finished broiler, risk of diseases including Avian Influenza (AI), bio-security of the farm and high feed cost ranked by turns second, third, fourth, fifth and sixth respectively. The present study revealed that the socio-economic status of the broiler farmers affect broiler production as well as profitability. In the second step, a survey study was undertaken to determine the productive and economic performances of broiler farming with or without bio-security management conditions during summer season reared in different locations; Pabna, Rajshahi and Kishoregonj district of Bangladesh. Total 41farms were selected into three locations considering bio and non-biosecured managed farms of which 14 in Rajshahi, 14 in Pabna and 13 in Kishoregonj. Data were collected from a total of 41 broiler farms by using semi structured questionnaire. Categories of farm (bio-secured & non bio-secured) were identified by using measures of bio-security standard which were based on marks. As per bio-security standard of broiler farm, the farms those got above 60 marks treated as bio-secured farms and below 60 marks treated as non-biosecured farms (out of 100 marks). Of the 41 farms, 27%, 21%, 15%, 15%, 12% and 10% farms have 500,600,700,800 900 and 1000 broilers respectively. During summer, a significant difference was found on marketable body weight and FCR among the farm sizes. FCR was better trend with increasing farm sizes. Overall FCR was improved in bio-secured managed farm than those of non bio-secured managed farm. Results indicated that farm category and farm size had clear impact on broiler productivity. The highest BCR was found in 1000 farm sizes (1.30) and the lowest was in 500 farm sizes (1.01). The lowest cost of broiler production was found when bio-security management was practiced. Therefore, significantly higher BCR value was found in bio-secured managed farms (1.17) than those of non bio-secured managed farms (1.03). In the third step, a total of 49 farms were selected into three locations of which 16 in Rajshahi, 16 in Pabna and 17 in Kishorgonj. Data were collected from a total 49 broiler farms by using same questionnaire in winter season with considering bio-secured and nonbiosecured managed farms to determine the production and economic performances of broiler farming. Of the 49 farms, 20% farms had 500 broilers, 19% had 600, 16% had 700, 18% had 800, 14% had 900 and 13% farms had 1000 broilers. In case of productive performances, body weight and FCR showed better trend as the farm size increased and significant differences were found among the farm sizes. When farms of similar sizes were maintained with bio-secured conditions, overall, FCR tended to better than in non-biosecured managed farm. The highest BCR was found in largest farm (1.38) and very poor BCR was found in smallest farm (1.08). BCR was found higher trends as the farm size increased. Moreover, higher BCR value (1.25) was observed in bio-secured managed farm than those of non-biosecured managed farm (1.09). The cost return analyses indicated that broiler farms size may consider at least 700 birds to have profitability. Growth performances were found higher to winter in comparison with summer. Profitability also was found to be higher in winter compared with summer season. Excessive colds, lack of knowledge on disease outbreak, poor management due to insufficient technical knowledge of the farmers, high temperature, frequent power failure in rural areas, improper marketing facilities, risk of diseases and lack of biosecurity of the farm were the major constraints of broiler farming in both seasons. In the fourth step, a study was undertaken to determine the quality of meat through proximate analysis of broiler farming carried out with and without bio-security management intervention in Rajshai, Pabna and Kishorgonj districts of Bangladesh. A total of 36 broiler meat samples were collected from broiler farmers with considering bio-secured & non bio-secured managed broiler farms during summer and winter between June, 13 to December’14 and having 12 meat samples in each location. No significant differences were found in moisture, crude protein, ash, crude fiber and either extracts in both seasons among the broiler farm locations. However, between of the two management intervention (bio and non-biosecured farm) during summer and winter seasons had a significant effect on proximate parameters. CP, moisture, Ash, EE and CF were found higher in bio-secured managed farm in comparison with non-biosecured managed farm in both seasons. Average proximate parameters of broiler meat samples in both seasons showed the following composition: moisture 76.09%, CP 20.07%, Ash 1.07%, CF 0 .033% and EE 1.05% respectively considering as fresh basis. Overall relatively better meat quality was found in bio-secured managed farms compared to non -biosecured managed farms. Moreover, between the two seasons, in terms of meat quality, CP, Ash and EE were found higher in winter season in comparison with summer season. It was concluded that satisfactory productive performances and improve meat quality is achievable and profitability may be enhanced from small and medium scale broiler farming at rural households of the farmers if bio-security management intervention is made. Finally, some suggestions and recommendations were made to ensure productivity and profitability of small and medium scale commercial broiler farming in Bangladesh. This thesis is Submitted to the Department of Veterinary and Animal Sciences, University of Rajshahi, Rajshahi, Bangladesh for The Degree of Doctor of Philosophy (PhD)

Epidemiological and Pathological Studies of Fascioliasis in Goats in Sylhet Region of Bangladesh and investigation on Effects of Different Liver Tonic on Pathology of Fascioliasis

2022-05-02T01:34:00Z

Epidemiological and Pathological Studies of Fascioliasis in Goats in Sylhet Region of Bangladesh and investigation on Effects of Different Liver Tonic on Pathology of Fascioliasis Islam, Kazi Mehetazul An attempt was made to determine the prevalence, patho-surveillance and histopathology of caprine fascioliasis in five agro-ecologic zones in Sylhet region of Bangladesh. Goats were divided into young and adult groups. Rectal fecal samples from household live goats and livers from slaughtered goats were collected randomly and examined from July 2012 to June 2013. A survey was also conducted to determine the snail populations and to know the infection status of the developmental stages of F. gigantica in Lymnaea snails. In addition,, the effects of liver tonic, anthelmintic and their combination treatments on some indicator parameters were evaluated. Statistical comparisons, using SPSS analysis, Pearson’s correlation and ANOVA statistics, were made to determine the differences in prevalence among seasons, age, sex and different upazillas. A total of 1288 rectal fecal samples from household live goats and 2000 livers of slaughtered goats were examined. Four hundred five (31.75%) household live goats and 202 (10.10%) slaughtered goat livers were infected with Fasciola gigantica. The overall prevalence was 20.93%. The prevalence of fascioliasis in Biswanath (25.96%) was significantly (P<0.001) higher than Beanibazar (22.16%), Balaganj (20.23%), Jaintapur (19.45%) and Sylhet Sadar (16.84%). It was noticed that prevalence in household goats was higher than slaughtered goats. The infection rate in young household (39.05%) and slaughtered (15.58 %) goats was higher than adult household (23.22%) and slaughtered (9.59%) goats. The females showed high infection rate than male. The fascioliasis was more significantly recorded in females household (39.15%) and slaughtered (13.10%) goats than males (19.96% and 7.10%, respectively). Closer analysis of results indicated that there was statistically significant difference (p<0.001) in prevalence rates in different upazilla as well as between female and male goats. Seasonally, the highest prevalence (25.71%) was recorded during rainy season and the lowest (10.12%) was in summer season. The prevalence rate in rainy season was statistically significant (p<0.001) than winter and summer. Intermediate hosts for Fasciola gigantica, the L. auricularia var rufescens was found in all agro-ecological sites at five different upazilla of Sylhet region. A total of 1865 Lymnaea snails were collected and examined. Of which 56 (3%) Lymnaea snails were infected with different developmental stages of F. gigantica. The infected snail percentage was highest 4.08% in Biswanath followed by 3.16% in Beanibazar, 2.53% in Balaganj, 2.40% in Jaintapur and the lowest 1.83% in Sylhet Sadar. In month-wise data, the prevalence of snails infection was highest in May (5.06%) and August (5.61%) and the lowest in February (0.68%) and March (0.74%). No infection was observed in November to January. The larval stages of F. gigantica infection in Lymnaea snail’s was highest in rainy (4.63%) season followed by summer (1.92%) and the lowest in winter (0.76%). The study revealed that the infection level of the developmental stages of F. gigantica in snails population decreases from November to January and increases from February to October and highest in August and September. In gross examination, the infected livers were enlarged with rounded edges and thickened capsule. In acute cases, numerous hemorrhagic spots were observed on the parietal and visceral surfaces of the affected liver. In chronic form, liver was cirrhotic and reduced in size. The affected intra-hepatic bile ducts were protruded and engorged with flukes. Microscopically, migratory tracts were represented by the presence of hemorrhage, edema and infiltration of numerous eosinophil mixed with few lymphocytes. Fatty change, atrophy and necrosis of hepatocytes were recorded along with deposition of bile pigment in hepatic parenchyma and damage of portal tract area. The wall of bile ducts was thickened due to fibrosis and lining epithelia were hyperplastic. Cross sections of adult and immature flukes were found within the lumen of the thickened bile ducts and hepatic parenchyma respectively. The efficacy of the anthelmintic, liver tonic and anthelmintic along with liver tonic against F. gigantica infection in goats and its effect on hematological and biochemical parameters were determined. Thirty five goats (2.0 to 2.5 years old) were randomly selected and divided into seven groups (namely T0, Ti, and T1 to T5) based on fecal sample examination. The first group (T0) kept as non infected control (negative control) and the second group (Ti) was infected control (positive control). Blood samples were collected to assess the hemto-biochemical parameters. The efficacy of anthelmintic, liver tonic and their combination treatment was evaluated by counting faecal egg per gram (EPG) and comparing hematological and biochemical parameters with pretreatment values. On 7th, 14th, 21st and 28th days of treatment, a significantly (P<0.001) decreased EPG count was found in treated group of goats. The EPG count of positive control group (Ti) were significantly (P<0.001) increased. The packed cell volume (PCV), hemoglobin (Hb), total erythrocyte count (TEC) levels were gradually decreased significantly (P< 0.001) in goats of positive control group. Conversely, hematological values were increased in treated group of goats, except the total leukocyte count (TLC) which was decreased significantly (p<0.001). This result was the indication of effective treatments. The level of serum glutamate pyruvate transaminase/aspartate transaminase (SGPT/AST), serum glutamate oxaloacetate transaminase/alanine transaminase (SGOT/ALT) and alkaline phosphatase (ALP) were declined significantly (P<0.001) in treated groups (T1, T3, and T5) as compared to the infected control group (Ti). The current research generated data on the epidemiology of Fasciola gigantica, pathology (gross and microscopic) caused by the immature and mature stages of the parasite in goats at Sylhet region of Bangladesh. This study was also provided information about the developmental stages of this parasite in its intermediate host (Lymnaea auricularia var rufescens) which is very important to design effective control program. A combined approach of administration of anthelmintic and liver tonics was applied to investigate how helpful the liver tonic is in regeneration of liver tissue which was damaged by fluke. The results showed that the liver tonic might have great impact on regeneration of hepatocytes and recommence of functional activities of the liver. Taken together, the findings of the present study have significant values and might helpful in establishing an effective treatment, control and eradication programs of fascioliasis in goats in Sylhet region of Bangladesh and also in similar temperate agroecological zones around the world. This thesis is Submitted to the Department of Veterinary and Animal Sciences, University of Rajshahi, Rajshahi, Bangladesh for The Degree of Doctor of Philosophy (PhD)