Browsing by Author "Chenyambuga, Sebastian W"

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Comparative evaluation of water quality parameters and growth performance of sex-reversed Nile tilapia (Oreochromis niloticus) raised in two different climatic conditions in Tanzania
(2020-06) Komba, Emma A; Munubi, Renalda N; Chenyambuga, Sebastian W
A study was done to compare water quality parameters, growth and production performance of Sexreversed Nile tilapia (Oreochromis niloticus) cultured in two districts of Tanzania, which experience different climatic conditions (cold and moderately warm). Fingerlings (1.00 g average weight) were stocked in earthen ponds (2 fish/m3), then raised for six months. Fish were fed twice daily and ponds were inorganically fertilized fortnightly. Measurements of water quality parameters and fish growth parameters (weight, length and width) were done biweekly. The results revealed significant differences on various water quality parameters; including temperature, salinity, conductivity and alkalinity between the two districts (p≤0.05). Mean growth rate, specific growth rate, mean final weight, estimated annual yield and Food Conversion Ratio were significant better for fish grown in warm than those in cold climate (p≤0.05). It is concluded that, fish growth and water quality parameters are better in warm than cold condition.
Comparison of body length-weight relationship and condition factor for Nile tilapia (Oreochromis niloticus) cultured in two different climatic conditions in Tanzania
(2020-04) Komba, Emma A; Munubi, Renalda N; Chenyambuga, Sebastian W
This study compared length-weight relationship and condition factor of male Nile tilapia raised in two districts experiencing different climatic conditions in Tanzania, Mbarali and Mufindi. Fish were raised for six (6) months and measurements were done biweekly. The results suggests negative allometric growth pattern (b < 3) for the fish grown in both experimental locations. The “b” values for the lengthweight relationships were 2.87 and 2.94 in Mbarali and Mufindi, respectively. The correlation coefficient and coefficient of determination indicated strong relationship (>99%) between length and weight of the fish. The condition factor (K) ranged from 2.74 to 3.50 in Mbarali and 1.96 to 2.40 in Mufindi, throughout the experimental period. Significantly higher condition factor was observed for fish grown in Mbarali (3.168 ± 0.056) than those in Mufindi (2.166 ± 0.056). It is concluded that, the climate of Mbarali provides better conditions for growth of fish than that of Mufindi.
Determination of genetic structure and Signatures of selection in three strains of Tanzania shorthorn zebu, boran and friesian Cattle by genome-wide snp analyses
(PLOS, 2017) Msalya, George; Kim, Eui-Soo; Laisser, Emmanuel L. K; Kipanyula, Maulilio J; Karimuribo, Esron D; Kusiluka, Lughano J. M; Chenyambuga, Sebastian W; Rothschild, F
More than 90 percent of cattle in Tanzania belong to the indigenous Tanzania Short Horn Zebu (TSZ) population which has been classified into 12 strains based on historical evi- dence, morphological characteristics, and geographic distribution. However, specific genetic information of each TSZ population has been lacking and has caused difficulties in designing programs such as selection, crossbreeding, breed improvement or conservation. This study was designed to evaluate the genetic structure, assess genetic relationships, and to identify signatures of selection among cattle of Tanzania with the main goal of under- standing genetic relationship, variation and uniqueness among them.
Develop feeding strategies for moringa oleifera and leucaena leucocephala as protein sources in tilapia diets
(2011) Lochmann, Rebecca; Engle, Carole; Kasiga, Tom; Chenyambuga, Sebastian W; Shighulu, Hegi; Madalla, Nazael; Mnembuka, Berno V; Quagrainie, Kwamena
Digestibility and feeding trials were performed to evaluate Moringa oleifera and Leucaena leucocephala leaf meals as protein sources (compared to soybean meal) in Nile tilapia diets. Both leaf meals were obtained from Tanzania. The leaf meals were soaked in water to reduce anti-nutritional factors, dried, and ground to a small particle size before incorporation into diets. Five diets were made for both trials: the control diet contained 50% soybean meal (SOY), and diets 15 MOR and 30 MOR were made by substituting 15 and 30% of the soybean protein with Moringa protein. Diets 15 LEU and 30 LEU were made by substituting 15 and 30% of the soybean protein with Leucaena protein. For the digestibility trial, diets containing 32% crude protein were used. Diets with 36% protein were used for the feeding trial due to the small initial fish size. The digestibility trial was carried out using mixed sex Nile tilapia of 200-400 g in 150-L indoor tanks in a recirculating system with dechlorinated municipal water maintained at 28 0 C. Other water quality parameters were kept at optimum levels for Nile tilapia. Fish were conditioned to the experimental diets and the fecal removal process (fresh, floating feces were collected with a net) for 1 week. Fecal collection was conducted 8-10 hours after the last meal in the evening, as well as the next morning before feeding. The fecal samples were dried at 50 0 C for 12 hours and then frozen until analysis. The apparent protein digestibility (APD, mean+SE, %) of the SOY diet (86.35±0.87) was higher than all others. The APD of the 15 MOR (84.69±0.59) and 30 MOR (83.34±1.10) diets were similar to each other and higher than the APD of the 15 LEU (78.49±0.91) and 30 LEU (74.70±0.52) diets. The APD of 30 LEU was also lower than that of the 15 LEU diet. Overall, leaf meals reduced protein digestibility compared to soybean meal, but diets containing Moringa were digested better than those containing Leucaena. There was no difference in the apparent lipid digestibility (%) of the SOY (95.83±0.34) and 15 MOR (95.19±0.62) diets. Lipid digestibility of the SOY diet was higher than that of 30 MOR (92.99±1.17), 15 LEU (94.46±0.06), and 30 LEU (92.98±0.24) diets. Lipid digestibility of the 30 MOR and 30 LEU diets was lower than that of the other diets. Both protein and lipid digestibility were inversely related to concentration of dietary fiber. For the feeding trial, 100 mixed-sex Nile tilapia, averaging 5.16 g individually were stocked in 1500-L outdoor circular plastic tanks supplied with reservoir water. The tanks were maintained as static systems except for periodic flushing when water quality parameters fell below the optimum for Nile tilapia. Subsamples of 30-50 fish were weighed every two weeks and water quality parameters were monitored weekly. The trial was terminated after 60 days. There were no differences in growth, feed conversion, survival, lysozyme, or proteolytic enzyme activity among treatments. Proximate and fatty acid composition of whole fish is still in progress.
Effects of fertilization and concentrate feeding on water quality and growth performance of Nile tilapia (Oreochromis niloticus) grown in concrete tanks
(African Journal of Biological Sciences [Associate Organisation], 2020-10) Chenyambuga, Sebastian W; Munubi, Renalda N.; Madalla, Nazael A.; Quagrainie, Kwamena; Frimpong, Emmanuel; Egna, Hillary
An experiment was conducted to compare the effects of fertilizer application alone, concentrate feeding alone and combination of fertilization and feeding on water quality parameters and growth performance of sex-reversed Nile tilapia (Oreochromis niloticus). Three treatments (weekly fertilization with urea and DiAmmonium Phosphate (DAP), concentrate feeding at 5% of fish body weight and weekly fertilization with urea and DAP plus concentrate feeding at 2.5% of fish body weight) were randomly allotted to nine concrete tanks. Three fingerlings per m2 were stocked in the tanks and grown for 166 days. Results indicated that treatment had significant effect (p  0.001) on water Dissolved Oxygen (DO), conductivity, total dissolved solids, nitrate and phosphorus but not on pH, salinity, temperature, ammonia and alkalinity. Fish cultured under the combination of feeding and fertilization had higher (p  0.0001) weight gain (257.37 ± 5.71 g), growth rate (1.50 ± 0.04 g/day), yield (13,128.35 kg/ha/year) and lower Feed Conversion Ratio (FCR) (1.89 ± 0.03) than those reared under feeding alone and fertilization alone. It is concluded that the combination of weekly fertilization and concentrate feeding at 2.5% of fish body weight is better than either weekly fertilization alone or feeding alone at 5% of fish body weight.
Effects of inorganic fertilizer application and supplementary feeding on water physico-chemical parameters, growth performance and yield of Nile Tilapia (Oreochromis niloticus) cultured in earthen ponds
(International Journal of Fisheries and Aquatic Research, 2020) Shabani, Salimu; Munubi, Renalda N; Chenyambuga, Sebastian W; Madalla, Nazael A.; Quagrainie, Kwamena; Frimpong, Emmanuel; Egna, Hillary
This study was carried out for 180 days to assess the growth performance, water physico-chemical parameters, yield and profitability of Nile tilapia (Oreochromis niloticus) culture in earthen ponds. The fish were reared in nine earthen ponds with average size of 177 m 2 and subjected to three treatments i.e. pond fertilization alone (T 1 ), concentrate feeding alone (T 2 ) and a combination of pond fertilization plus concentrate feeding (T 3 ). Sex- reversed Nile tilapia fingerlings were stocked at a density of 3 fish/m 2 . For T 1 and T 3 , urea and Diammonium phosphate (DAP) fertilizers were applied in pond water weekly at a rate of 3 g/m 2 and 2 g/m 2 , respectively. For T 2 and T 3 the fish were fed a diet containing 25.1% crude protein (CP) at a rate of 5% and 2.5% of body weight, respectively. Pond water physico-chemical parameters were measured weekly. A total of 30 fish from each pond were harvested biweekly and individually measured for body weight and length. Dissolved oxygen (DO), pH, Secchi disk reading, conductivity, salinity, phosphorous, nitrate and alkalinity differed (p ≤ 0.05) but temperature did not differ (p > 0.05) among treatments. In all treatments the water quality parameters were within the acceptable range for tilapia culture. Within a 24 hours period, DO, pH and temperature were highest at 1500 hours and lowest at 0600 hours. The fish reared under T 3 showed higher (p < 0.05) body weight gain (194.1 ± 4.5 g), growth rate (GR) (1.5 ± 0.1 g/day), estimated yield (13 065 ± 458 kg/ha/year) and gross margin (12 364.41 ± 1 376.75 USD/ha) than those under the other treatments. The FCR was higher (4.1 ± 0.3) for the fish subjected to T 2 and lower (2.0 ± 0.1) for the fish reared under T 3 . The highest condition factor (K) (2.54 ± 0.0) was observed for the fish reared in ponds under T 1 whereas fish under T 2 had the lowest value (2.05 ± 0.0). It is concluded that, the combination of pond fertilization plus concentrate feeding (T 3 ) is the best strategy for rearing Oreochromis niloticus, since it reduces feed utilization and results into higher growth performance and profit.
Evaluation of biofilter performance with alternative local biomedia in pilot scale recirculating aquaculture systems
(Elsevier, 2022) Munubi, Renalda N; Pedersen, Lars-Flemming; Chenyambuga, Sebastian W; Mnyoro, Samwel Mang’era
Plastic is commonly used as biofilter media in recirculating aquaculture systems. Because plastic is relatively expensive and may erode and emit microplastics to the environment, efforts are being made to test and develop more sustainable materials. Five alternative locally available biofilter media were compared with commercial plastic media and evaluated in duplicate in 1 m 3 two pilot scale Recirculation aquaculture system. Ammonium chloride and sodium nitrite were added to the systems for 4 weeks followed by stocking 20 kg of Nile tilapia in each system. Volumetric total ammonia nitrogen (TAN), nitrite and oxygen conversion rates were assessed for ten weeks. All biofilters with local media matured and reached full capacity after six weeks, while commercial plastic biomedia matured after seven weeks. This study found that the performance of commercial plastic biomedia was similar to performance of coconut shells in terms of volumetric TAN conversion rate (VTR), volumetric nitrite conversion rate (VNR) and volumetric oxygen conversion rate (VOCR). The highest VTR recorded in this study was 599 ± 15.8 g TAN/m 3 /d from coconut shells while the lowest was 343 ± 8.9 g TAN/m 3 /d from cattle horns. Biofilters with commercial plastic media had the highest VNR (704 ± 50.3 g NO 2 –N/m 3 /d) while media made of cattle horns was the lowest (457 ± 46.1 g NO 2 –N/m 3 /d). Biofilters containing coconut shells demonstrated the highest oxygen consumption around 3.0 g/m 3 /d and biofilters containing charcoal consumed less than 1.0 g/m 3 / d of oxygen. This study suggests that coconut shells can be used in place of plastic materials in simple recir culation aquaculture system biofiltration. This study also recommends further studies on comparing coconut shells with other biomedia and assessing its effects on water quality parameters and durability.
Evaluation of performance of different tilapia species
(University of Arkansas, 2011) Chenyambuga, Sebastian W; Meiluidie, Ester; Madalla, Nazael; Mnembuka, Berno V; Lochmann, Rebecca
A growth trial was carried out for 90 days to compare the growth performance and survival rate of Nile tilapia (Oreochromis niloticus) and Jipe tilapia (Oreochromis jipe), Wami tilapia (Oreochromis urolepis hornorum) and Ruvuma tilapia (Oreochromis ruvumae).. The study was conducted on-station at Sokoine University of Agriculture (SUA) and on-farm in ponds of small-scale fish farmers at Mkuyuni, Morogoro, Tanzania. In the on-farm experiment, the mean final weight, weight gain, growth rate, final length and final width differed significantly (P<0.001) among the species. Nile tilapia (O. niloticus) gained more weight (61.3g) than O. hornorum (35.3g) and O. ruvumae (13.8g). The final weight, length and width of O. niloticus exceeded that of O. hornorum by 26.2g, 2.4cm and 0.7cm, respectively. The mean final weight, length and width of O. hornorum were higher than those of O. ruvumae by 23.6g, 2.7cm and 1cm, respectively. The results from the on-station experiment showed that there was no significant (P>0.05) difference between O. niloticus and O. hornorum, but the two species differed significantly (P<0.01) from O. ruvumae and O. jipe. The O. niloticus had the highest weight gain (24.2 g), growth rate (0.3g/d), final length (11.5cm) and final width (3.3cm) and it was followed by O. hornorum. The O. ruvumae and O. jipe showed poor performance in all parameters. The growth performances of O. niloticus and O. hornorum were significantly (P<0.05) higher in the on-farm experiment than in the on-station experiment, but that of O. ruvumae were not significantly (P≥0.05) different between the two locations. The highest survival rates (85.6% (on-farm) and 100% (on-station)) were observed on O. niloticus, followed by O. ruvumae. Oreochromis urolepis hornorum had the lowest survival rate (63.5 – 66.7%) in both experiments. For all species, fish reared at the on-station showed higher survival rate (66.7 – 100%) compared to those reared in farmers’ ponds (63.5 – 85.6%). The results for chemical composition of the fish bodies indicated that the species did not differ significantly in dry matter (DM) and ash contents, but differed significantly (P<0.05) in crude protein (CP) and fat (EE) contents for the on-farm experiment. Oreochromis urolepis hornorum had the highest CP content (58.09%) and EE (30.12%) while O. niloticus had the lowest values (52.23% CP and 16.83% EE). For the on-station experiment, the DM, CP and ash contents of the species were not significantly (P≥0.05) different. It is concluded that Oreochromis niloticus is superior to Oreochromis urolepis hornorum, Oreochromis jipe, and Oreochromis ruvumae in terms of growth performance and survival rate.
Management and value chain of nile tilapia cultured in ponds of Small-scale farmers in Morogoro region, Tanzania
(2012) Chenyambuga, Sebastian W; Madalla, Nazael A; Mnembuka, Berno V
A study was carried out to assess production performance and value chain of Nile tilapia grown in ponds of small-scale farmers in Morogoro region, Tanzania. Information was collected through individual interviews of 30 fish farmers. The main reasons for culturing fish were provision of animal protein food for home consumption (66.7%) and generation of income (23.3%). Fish farming contributed 10.6% of household annual income and was ranked second to crop production (50%). The majority of the farmers were fertilizing their ponds with chicken manure (30.0%) and cattle manure (23.3%). Most farmers (73.3%) cultured pure stand of Nile tilapia and only few (26.7%) practiced polyculture of Nile tilapia and African catfish. All farmers depended on natural food as a source of feed for their fish. Moreover, the farmers were feeding maize bran (96.7%), vegetables (66.7%), and kitchen leftovers (13.3%) as supplementary feeds. Men were responsible for purchasing and stocking fingerlings (60.0%), feeding (40.0%), pond maintenance (53.3%), harvesting (60.0%) and selling (43.3%). Women were mainly involved in fish processing (76.7%). The average period from stocking to harvesting was 5.75 ± 0.18 months for Nile tilapia and the mean yield was 6,946.2 kg/ha per year. About 22.2% of the harvested fish were consumed at home and the remaining (77.8%) were sold. The main actors in the value chain of cultured Nile Tilapia were fingerling producers, fish farmers and consumers. Most farmers sold fresh fish directly to neighbours (70.0%) and consumers in the local market within the village (30.0%). It is concluded that small-scale fish farming is important for provision of animal protein food and income and is done mostly by men, and it is characterized by low productivity due to improper pond fertilization and feeding. The major problems to Nile tilapia farming under small-scale fish farming is lack of funds, stunted growth of stocked fish, inadequate knowledge on fish farming and unavailability of concentrate feeds.
Prevalence and risk factors associated with theileria parva Infection in cattle in three regions of Tanzania
(Springer Science+Business Media, 2017) Kerario, Isack I; Simuunza, Martin C; Chenyambuga, Sebastian W; Koski, Marja; Hwang, Seong-Gu; Muleya, Walter
Ticks and tickborne diseases (TBDs) are serious constraints to cattle production in Tanzania and other tropical and subtropical countries. Among the TBDs, East Coast fever (ECF) is the most important as it causes significant economic losses to the cattle industry in Tanzania. However, control of ECF in Tanzania has continued to be a challenge due to inad- equate epidemiological information. The main objective of this study was to determine the epidemiological situation of Theileria parva infections in cattle kept under pastoral and agro-pastoral farming systems in Mara, Singida, and Mbeya regions of Tanzania. Blood samples were collected from 648 cattle in the three regions. Genomic DNA was extracted and amplified in a polymerase chain reaction (PCR) using T. parva-specific primers targeting the 104-kD antigen (P104) gene. In addition, information was collected on the possible risk factors of T. parva infection (animal age, region, animal sex, tick burden, tick control method, and frequency of acaricide application). The prevalence of T. parva across the three regions was 14.2%. There was variation in prevalence among the three regions with Mara (21.8%) having a signifi- cantly higher (p = 0.001) prevalence than the other regions. Moreover, Mbeya exhibited relatively lower prevalence (7.4%) compared to the other regions. Factors found to be significantly associated with an animal being PCR positive for T. parva were region (p = 0.001) and tick burden (p = 0.003). Other factors were not found to be significant predictors of being PCR positive for T. parva. The present study showed high variation in tick burden and T. parva prev- alence across the regions. Therefore, different strategic plan- ning and cost-effective control measures for ticks and T. parva infection should be implemented region by region in order to reduce losses caused by ticks and ECF in the study area.