Theses and Dissertations Collection

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Alkali treatment of roughages and energy utilization of treated roughages fed to sheep and goats
(University of Dar es Salaam, 1981) Ndelilio, Urio A.,
Two series of experiment were conducted, laboratory scale experiments, and and production experiments. The laboratory scale scale experiments were carried out to develop simple methods of alkali-treatment, and to test the- effectiveness of cheap alternative chemicals lo sodium hydroxide. Pro duction experiments were conducted to tost the effectiveness of an apparently promising "dip" treatment motheJ developed in the laboratory scale experiments. and k.a Ca(CII) The effectiveness of Na9CO3 emu lUn,2 cis roughage treating chemicals were tested in combination with NaOH in a 3 x 3 factorial experiment. The levels of the chemicals tested were 0, 3 and 6 g/100 g of roughage (DM). was used as a test roughage. Wheat straw Neither of the chemicals re- suited in any improvement in the digestibility of the straw’ although Ca(OII)2 showed a slight effect in increasing the enzyme soluble organic matter of wheat straw. Both chemicals showed a somewhat negative interaction with NaOH. Maize stover and Hyparrhenia grass were also treated with increasing levels of Na2COg from 0 to 10 g/100 g of roughage DM. Maize stover did not show any response to Na2CO3 treatment except for its enzyme soluble organic matter which increased with increasing levels of Na2CO3. The enzyme soluble organic matter for the untreated maize stover was 29%, while that for maize stover treated with 10 g Na2CO-/ 100 g of roughage DM was 43.6%. Hyparrhenia grass responded comparatively better to Na?CO3 treatment than maize stover. Addition of herring meal to the roughages resulted in a(X) marked improvement in the digestibility of both roughages. This also improved the response of the roughages to ^2^0^ treatment. Maize stover showed a higher response to the addition of herring meal than IJyparrhenia grass. The chemical composition of 4 samples of local Magadi soda was determined. All the samples had high sodium chloride contents, indicating a possibility of Magadi soda having a positive effect on voluntary feed intake. It was rioted that some samples had rather high fluorine contents. Studies were conducted on the effectiveness of a simple "dip" method which involved dipping straw in a 1.5% NaOH solution overnight, letting it drip, washing with minimum water, and letting it drip again. The lye solution was reused 15 times, the strength of the solution being restored after each treatment. The DM and Na content of the lye solution increased with increasing reuse of the solution. The DM content of the solution increased from 1.9% to 7.2%, while the Na content increased from 0.7 to 1.4%. Both the DM and Na contents of the solution tended to stabilize after the solution had been reused more than 10 times. The IVOMD and ESOM of the treated straw increased with increasing reuse of the solution. The in vivo DM and OM digestibility as well as DE of the straw was improved markedly by the dip method. The digestibility of OM of the untreated straw was 50% as opposed to 73% for the dip treated straw. The diges tibility of DM and OM in vivo was not affected by the reiise of the solution although that of CF tended to decrease slightly after the solution had been reused more than 10 times.(Xi ) In the production experiments a comparative slaughter technique was applied with sheep and goats. Three groups of goats were fed rations based on untreated maize cobs, "dip" treated maize cobs (NaOII-treatment) , and Chlorin gayana hay. The experimental feeding period was 100 days. The DM intake from these rations was the same in the three groups, but the dip NaOII treatment of maize cobs resulted in a higher DM digestibility (G4.1% as opposed to ) higher metabolizable energy intake (4.19 MJ as opposed to 3.40 MJ/d) when compared to the group fed untreated maize The group fed dip treated maize cobs also had sig cobs. nifleant higher gains in liveweight, carcass weight, car- cass fat, and carcass gross energy content. This group, however, did not differ significantly from the group fed Chloris gayana hay in these parameters. It was also observed that, the group fed dip treated maize cobs had a tendency to lay down intestinal fat. Three groups of sheep were also fed on untreated maize stover, dip treated maize stover and ensiled (NaOH-treated) Hyparrhenia grass silage for 100 days. centrate in the DM intake was about 20%. The level of con Although dip treat ment of maize stover increased its digestibility, this did not result in significant differences in performance between the group fed untreated maize stover in all the parameters studied. The groups fed maize stover (untreated or treated) had however significantly bettor performance in all para- meters measured than the group fed NaOII-treated Hyparrhonxa silage.(xii) CorreiaLions wore determined between whole carcass fat Z and carcass weight, and between carcass fat -i and carcass specific gravity. In goats, the correlation coefficient for carcass fat Z on carcass weight was 0.84, while that between carcass fat " and carcass specific gravity was -0.97. These para meters (carcass weight, and carcass specific gravity) can there?fore probably bo used to estimate carcass fat S and consequently carcass energy content in goats. The correlation coefficient between carcass fats and carcass weight in sheep was only 0.52, while that between carcass fat S and carcass specific gravity was -0.79. In addition to those comparatively low relationships in sheep, it was noted that carcass specific gravity was rather sen sitive and difficult to measure in fat carcasses, and liable to technical errors. It is thought that those relationships cannot therefore be applied universally to the heterogeneous sheep of East Africa.
Analysis of diurnal and seasonal dynamics of water quality parameters and their implications on metabolism and physiology of nile tilapia (oreochromis niloticus) cultured in pond.
(Sokoine University of Agriculture, 2024) Hamad M. I
Aquaculture production of Nile tilapia (Oreochromis niloticus) has attracted considerable attention around the world because of their fastest growth rate, good quality meat, and fascinating physiological characteristic that allow them to adopt and strive in a broad range of production systems. Because of these characteristics, Nile tilapia has been adopted as the key aquaculture species in Tanzania. Nile tilapia production in Tanzania takes place primarily in earthen ponds, mostly under a semi-intensive system without the use of water treatment technology. In Tanzania more than 80% of the aquaculture produced fish comes from Nile tilapia raised ponds. The production of Nile tilapia in ponds has for long time been unsuccessful due to poor growth performance. This is because, unlike in other production systems such as Recirculating Aquaculture Systems (RAS), in small water bodies such as earthen ponds water quality parameters vary considerably on a daily basis, depending on the equilibrium reached with the regular physical and chemical characteristics of the surrounding environment. These variation are likely to considerablly effect physiology and welfare of the cultured fish. Unfortunatly, the extent of diurnal, and seasonal variation in water quality parameters in the production ponds across the country are not yet known. This makes it difficult for estimating the influence of changes in fish ponds water quality influences on physiology and performance of cultured Nile tilapia. This study was carried out to determine the current status and dynamics of the diurnal, and seasonal fishpond water quality parameters in Tanzania. It was also carried out to assess the effects of the observed water quality variation on the physiology, metabolism and performance of the pond-cultured Nile tilapia. To achieve the study objectives, a field survey of fish onds and three laboratory experiments were performed. The diurnal and seasonal trends in pond water quality parameters were documented and the effect of changes of some selected water quality parameters on the Nile tilapia physiological characteristics and performances were reported. Study 1. A field survey was conducted between June 2019 and April 2021 in Tanzania. Four agroecological zones (Easter, Southern Highland, Northern, and Lake Zones) were selected as study sites. A total of 120 fish farmers were interviewed using a well structured questionnaire to collect information on the current general farm characteristics and farming practices. In addition, a fish farm with identical ponds stocked with Nile tilapia was selected in each agro-ecological zone, and an in-situ measurement of the water parameters was carried out for one year, covering two seasons (the cold: June to September and the warm season November to January). Results revealed significantly difference in mean pond water temperature between the study zones (p <0.001) with the highest in the Eastern and the lowest in the Southern Highland zones. Results show that the temperature in the Northern zone and Southern highlands during the cold season (June to September) was below the level required for Nile tilapia growth. Other water quality parameters (pH, DO, turbidity, and TDS) varied between seasons within zones, but, were within the range suitable for Nile tilapia growth. The annual fish yield was higher in the Lake zone (629 ±124 kg/ha/yr) suggesting a positive relationship between temperature and fish yield. High net primary production during the warm season in all zones indicates the need for good water quality management to prevent algae blooms, which may result in acute and prolonged stress from hypoxia and hypercapnia, which are the primary physiological stressors for fish. The available data from the survey study was used as a baseline in a series of experiments conducted in the lab at Denmark Technical University (DTU-aqua) to critically assess the effects of the variation in water parameters on the physiology and performance of the cultured Nile tilapia. Experiment 1. High level s of dissolved carbon dioxide (CO 2 ) occurs nightly in earthen ponds characterized by high respiration rates. Exposure to high CO 2 conditions (hypercapnia) leads to acidosis in fish, which can be compensated by an accumulation of HCO 3- to recover intra - and extracellular pH levels, with a capacity that appears to be species-specific. For Nile tilapia, a freshwater tropical teleost traditionally produced in earthen ponds, little information is available on the tolerance to dissolved levels of CO 2 and associated acid-base disturbances. Here, we investigated first the effects of acute and progressively increasing CO 2 , from normocapnic conditions to 60 mg CO 2 L -1 , on oxygen uptake rates (MO 2 ). This was followed by exposure to three concentrations of CO 2 ; 10, 30, and 60 mg L -1 (equivalent to pCO 2 of 5.4, 16.2, and 32.4 mmHg) against a normocapnic control (pCO 2 0.3 mmHg), to investigate acute (1h) or prolonged (24h) effects on standard (SMR) and maximum metabolic rate s (MMR), haematology, and extra - and intracellular acid-base status in adult Nile tilapia (mean BM 435 ± 16 g ±SE). Acute exposure to hypercapnia led to concentration-dependent decreases in both SMR and MMR. Fish were able to fully or partially recover MMR and metabolic scope (MS) after 24h, while depression of SMR persisted at all CO 2 levels. Acute exposure to CO 2 caused intra-and extracellular pH levels to decrease by up to 0.5 units in a concentration-dependent manner. Only the lowest hypercapnic treatment (pCO 2 5.4 mmHg) was able to fully recover within 24h. Changes in haematological variables appeared minor, being restricted to increasing haematocrit, haemoglobin concentration, and mean cell volume in the highest CO 2 treatments after 24h exposure. Although the Nile tilapia is generally considered a species able to tolerate poor water quality, the modest or slow acid-base regulation following hypercapnic exposure suggests sensitivity to hypercapnia. Experiment 2. Dissolved gases (carbon dioxide and oxygen) in earthen ponds exert strong opposing effects due to photosynthesis and respiration. This leads to daily conditions that fluctuate between being hyperoxic and hypocapnic during the day and becoming severely hypoxic and hypercapnic at night. The interacting effects of hypoxia and hypercapnia and fluctuating conditions on pond-farmed Nile tilapia have not received any attention. This study evaluated the effects of daily variations in dissolved O 2 and CO 2 on the appetite and feed utilization in Nile tilapia using groups reared under normoxic - normocapnic conditions (control, C), diurnal hypoxia (HO), diurnal hypercapnia (HC), or combined diurnal hypoxia and hypercapnia (HO × HC) in a digestibility system. Results show that hypoxia and hypercapnia exerted strong individual effects on appetite, specific growth rate, and feed conversion and that simultaneous hypoxia and hypercapnia amplified these effects. Appetite depression induced by nocturnal hypoxia or hypercapnia was restored at mid-day, but simultaneous exposure resulted in a day-long loss of appetite. Hypoxia and hypercapnia reduced specific growth rates by up to 40% and increased feed conversion ratio by up to 80%, while combined exposure to hypoxia and hypercapnia reduced specific growth rates by >60%. Surprisingly, the digestibility of dry matter, protein, and lipid was improved in groups exposed to single or combined diurnal variation in dissolved oxygen and carbon dioxide. This study concludes that nocturnal exposure to hypoxia or hypercapnia has adverse effects on the growth performance of Nile tilapia driven by a combination of reductions in appetite and poor feed utilization. The results emphasize that there is a need for careful management of dissolved gases in pond culture. Application of aeration technology, combined with management of the nutrient status of the pond and sludge accumulation to control oxygen consuming and CO 2 liberating processes, is likely able to greatly improve production performance. Experiment 3. Temperature plays a significant role in controlling oxygen solubility in water and its availability to aquatic breathing species including fish. In fish ponds, the water temperature can increase gradually during the day resulting in elevated temperature and an extended period of low dissolved oxygen. In this study, the response of Nile tilapia (Oreochromis niloticus) interms of thermal tolerance limit (CTmax), metabolic rate (SMR), Cardiac performance (ƒ H ), and ventilation frequency (ƒv) to the acute increase in temperature upon changing dissolved oxygenv saturation was investigated. Nile tilapia were experimentally exposed to an increased temperature of 0.1 °C min -1 at 100% DO saturation (Normoxia), 70% (hypoxia), and 130% (hyperoxia) from 26 °C (Optimum) until the onset of loss of equilibrium (LOE). Oxygen consumption rate (MO 2 ), heartbeat, and opercula activity were averaged at each temperature increase for three DO saturation levels. Results show that high DO saturation (130%) increased Nile tilapia’s Critical Thermal Maximum (CTmax) by 10%. The Nile tilapia metabolic rate (SMR) varied significantly with the changing DO saturation at acute increased temperature levels (One-way ANOVA; F(2,44) = 4.596, P = 0.016). Temperature-DO-limited metabolic relationship affected cardiorespiratory activities and maximum thermal tolerance (CTmax) in Nile tilapia (one-way ANOVA; F (2,44) = 0.34, P = 0.713). Different levels of DO saturation were found to significantly affect Nile tilapia’s respiration ability (Opercula beats min -1 ) (P < 0.001). This study is concluding that diurnal and seasonal pond water quality varies significantly between zones and between seasons within the investigated zones and affectsthe production performance of the pond-cultured Nile tilapia. Nile tilapia might only be stocked in the warm season in the Northern and southern highland zone if farmers are to achieve the best growth of Nile tilapia. Although the Nile tilapia is generally considered a species able to adapt to and tolerate poor water quality, the modest or slow acid-base regulation following hypercapnic exposure suggests that it is quite sensitive to CO 2 exposure. Although Nile tilapia is considered resilient to environmental stress, feeding and feed utilization, oxygen uptake, and Critical thermal maximum are strongly influenced by daily fluctuations in dissolved CO 2 , O 2 and Temperature.
Assessment of anticholinesterase contaminants in Ruvu river using cholinesterase biomarker in African sharptooth Catfish
(Sokoine University of Agriculture, 2017) Katto, T. M.
A cross sectional study was conducted to assess the extent of exposure of anticholinesterase contaminants in Ruvu river using cholinesterase biomarker in African Sharptooth Catfish. Questionnaire interviews were used to collect sociological data from 200 respondents, also Ellman‟s method and 5, 5‟-dithiobis-2-nitrobenzoic acid chromophore was used to establish cholinesterase activities in plasma and brain of 40 Claria gariepinus. The sociological findings showed that all respondents (100%) use pesticides in agriculture and 62.5% were males with primary level of education (69%). Organophosphates pesticides were mentioned to be mostly used in the area. With regards to the proper use, awareness on the effects and disposal of pesticides, it was observed that most farmer know how to use the pesticides and were aware of the effect of pesticides in human and pests but not to the environment. Also mishandling and poor disposal of pesticides and their leftovers were reported. There was no significant difference between the levels of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in plasma. AChE and BChE activities in brain showed insignificant difference (P > 0.05) among fish from the study sites and the control. The brain AChE activities were significantly lower (P ˂ 0.05) in fish from Ruvu Darajani compared to the control. This study revealed differences in AChE and BChE activities in the study area. Such differences could be ascribed to the environmental contamination due to agrochemicals used by the farmers around Ruvu river basin.
Assessment of effects of effective microorganisms on broiler chicken performance and malodour reduction In poultry house
(Sokoine University of Agriculture, 2011) Mgunda, Honorius Dismas
The study was conducted to assess the effects of Effective Microorganisms (EM) as feed additive in broiler chicken production on growth performance, health and foul smell control in poultry house. The experiment involved two hundred and ten, day old hybro broiler chicks which were randomly allocated to 14 pens each with 15 birds in seven treatments with two replicates. The main treatment (EM) was provided to experimental birds in two levels: 10mlEM2/l and 20mlEM2/l either in drinking water or by spraying in litter material or both in water and litter. After 42 days of the experiment 70 live chickens were selected and 5 birds/pen from each replicate were slaughtered for carcass assessment. There were significant difference between treatments on growth performance and carcass yield. EM treated groups had significant higher body weight gain, cumulative body weight gain and average daily body weight gain compared to no-EM control group. Carcass yield percent were comparatively higher in EM treated birds than control groups. T7 had significantly high carcass yield percent (79.13%) compared to other treatments and control group (73.91%). Internal organs such as gizzard and liver had significantly higher weights for EM treated birds compared with no-EM control birds. The overall mortality rate of birds was 12.8% and the highest mortality rate occurred in the first week (9%) and in the second week (3.3%), due to sudden death syndrome, salmonellosis, and huddling. Significant differences were also observed between treatment effects and treatment combinations on ammonia concentration. Pens with birds receiving 20mlEM/l both in water and litter had significant low ammonia levels compared with control group. It is concluded that EM had growth promoting effects, reduced mortality rates and reduced significantly the ammonia levels in poultry house in higher dose of 20mlsEM2/l concurrently supplemented in water and sprayed in litter.
Assessment of factors affecting performance of dairy cattle kept in smallholder farms in peri-urban areas of Temeke municipality
(Sokoine University of Agriculture, 2013) Chaussa, Karume Semfuko
There was a lack of detailed information of factors affecting the performance of dairy cattle kept in smallholder farms in Temeke municipal. Two approaches were employed to identify factors that affect the productivity and reproductive performance of dairy cattle kept in the study area. The first approach used structured questionnaire which were administered to 84 dairy farmers using a cross sectional survey technique to collect data from 12 villages. The second approach was a longitudinal monitoring where 16 lactating dairy cattle from four streets owned by dairy farmers that filled the questionnaire were monitored for thirty days where feed intakes and milk yield were measured and recorded. Feed samples were collected for quality evaluation. The daily milk yield of lactating cows under cross sectional survey and longitudinal monitoring was 8 litres with range of 4- 13 litres and 9 litres with range of 5-13 litres per cow per day, respectively. The major limitations to improved production identified by farmers were diseases and erratic extension services. The overall percentage of crude protein (CP), calcium (Ca), Phosphorus (P), In vitro dry matter digestibility (IVDMD) and Metabolisable energy (ME) contents of mixed forages fed to the animals were 6.38, 0.2, 0.17, 44.77 and 7.14, respectively. IVDMD and ME contents of mixed forages fed to cattle in Mbutu village were significantly (P<0.05) higher than those from Kizani, Kidagaa and Kwachale villages. The overall daily nutrient intakes of ME, CP, Ca and P for a cow weighing 420kgs in the study area were 87.5, 758g, 22.9g, and 18.5g per cow per day, respectively which did not meet the requirement for the production of 12 litres of milk per day. According to NRC (2001) a cow weighing 420kg requires 108 ME, 1357gCP, 46.2gCa and 34gP. Therefore supplementary ration of 20.5ME, 599gCP, 23.3g Ca, and 15.5gP per day will be required to cover the shortfall of 3 litres of milk per day.
Assessment of feeding practices and performance of dairy cattle in Kibaha district, Tanzania
(Sokoine University of Agriculture, 2009) Dawson, N. D.
Two studies were carried out in Kibaha District to investigate feeding practices and performance of dairy cattle kept by smallholder farmers. In experiment 1, formal survey which aimed at assessing the existing feeding practices, performance and constraints, involved 30 dairy farmers from 3 wards. In experiment 2, twenty four (24) lactating cows from two wards, that is 12 cows from each ward, were monitored for one month where intakes and milk yield were measured. In experiment 1; the performance in terms of reproduction and milk yield of cows under both zero and full grazing, was low during wet and dry seasons. Major constraints identified were nutritional related causes by the existing feeding practices. In experiment 2, the overall percentages of crude protein (CP), in vitro dry matter digestibility (IVDMD), neutral detergent fibre (NDF), calcium (Ca), Phosphorus (P) and overall means of Metabolizable energy (ME MJ) contents of mixed forages under full grazing were 6.18, 48.01, 73.58, 0.25, 0.16 and 6.88, while those under zero grazing were 6.09, 49.08, 74.2, 0.24, 0.18 and 7.02, respectively. The overall daily nutrient intakes (g/ kgW0.75) of zero grazed cows were 120, 7.48, 0.26, 0.21 and 0.86 MJ for DM, CP, Ca, P and ME respectively. The daily milk yield of lactating cows under full grazing and zero grazing systems measured during monitoring experiment were 5.45 and 6.59 l/cow, respectively. Production performance of dairy cattle observed during wet season was suboptimal, probably due to underfeeding attributed by lack of adequate supplementation. It is, therefore proposed to supplement the animals with concentrate that will supply 41.6 MJ, 1012g CP, 38g Ca, and 22g P per cow/ day for optimal milk production.
Assessment of feeding practices and performance of dairy cattle in Kibaha district, Tanzania
(Sokoine University Of Agriculture, 2009) Dawson, Nkenwa Darlington
Two studies were carried out in Kibaha District to investigate feeding practices and performance of dairy cattle kept by smallholder farmers. In experiment 1, formal survey which aimed at assessing the existing feeding practices, performance and constraints, involved 30 dairy farmers from 3 wards. In experiment 2, twenty four (24) lactating cows from two wards, that is 12 cows from each ward, were monitored for one month where intakes and milk yield were measured. In experiment 1; the performance in terms of reproduction and milk yield of cows under both zero and full grazing, was low during wet and dry seasons. Major constraints identified were nutritional related causes by the existing feeding practices. In experiment 2, the overall percentages of crude protein (CP), in vitro dry matter digestibility (IVDMD), neutral detergent fibre (NDF), calcium (Ca), Phosphorus (P) and overall means of Metabolizable energy (ME MJ) contents of mixed forages under full grazing were 6.18, 48.01, 73.58, 0.25, 0.16 and 6.88, while those under zero grazing were 6.09, 49.08, 74.2, 0.24, 0.18 and 7.02, respectively. The overall daily nutrient intakes (g/ kgW0.75) of zero grazed cows were 120, 7.48, 0.26, 0.21 and 0.86 MJ for DM, CP, Ca, P and ME respectively. The daily milk yield of lactating cows under full grazing and zero grazing systems measured during monitoring experiment were 5.45 and 6.59 l/cow, respectively. Production performance of dairy cattle observed during wet season was suboptimal, probably due to underfeeding attributed by lack of adequate supplementation. It is, therefore proposed to supplement the animals with concentrate that will supply 41.6 MJ, 1012g CP, 38g Ca, and 22g P per cow/ day for optimal milk production.
Assessment of genetic diversity and population trend of frigate tuna (auxis thazard) in Tanzania marine waters
(Sokoine University of Agriculture, 2022) Maduhu, Elizabeth Mayunga
Frigate tuna (Auxis thazard) is one of the most harvested marine fish in Tanzania and contributes to food security of the people living in the coastal areas and the country’s economy in general. Frigate tuna is highly exploited due to its better meat property and there is a danger that, in a long run it will be depleted. Therefore, there is a need to establish strategies for sustainable utilization and conservation of the overexploited tuna species. Establishment of conservation strategies requires information on genetic diversity and the distinctiveness of the species. Furthermore, effective management of frigate tuna requires information about population size and dynamics. This study assessed the stock genetic diversity and structure of frigate tuna (Auxis thazard) populations using mitochondrial displacement loop (mtDNA D-loop) sequences. Furthermore, the study assessed population trends in Tanzanian marine waters using secondary data obtained from the Ministry of Livestock and Fisheries and collected for a five-year period from 2015 to 2019. Also, the size of frigate tuna caught in Tanzania’s marine waters was determined. For the genetic diversity study, a total of 100 frigate tuna were collected from small-scale fishermen at Dar es Salaam (20 fish), Tanga (30 fish), Mtwara (30 fish) and Zanzibar (20 fish) landing sites. For each fish, a muscle tissue sample (approximately 50 g) was collected from the area above the lateral line of the fish and near the dorsal fin and put in a vial containing 95% ethanol, and the vial was labelled. DNA extraction was done using a genomic DNA mini-extraction kit (Quick-DNA Kit). DNA quantification was done by using a spectrophotometer. The DNA concentration was adjusted to 50 ng and then stored at 4 o C. The DNA samples were sent to the Agricultural Research Council-Biotechnology Platform, South Africa for polymerase chain reaction (PCR) amplification and sequencing. A fragment of 432 bp containing the first half of the mitochondrial DNA control region (D- loop) was amplified using the following primer set. The forward primer sequence was 5′- CCGGACGTCGGAGGTTAAAAT-3′ and reverse primer sequence was 5′- AGGAACCAAATGCCAGGAATA-3′. Sequencing of the purified PCR fragments was performed using the same primers. The sequencing was done using an ABI PRISIMTM 3100 Genetic Analyzer (Applied Biosystems). A total of 88 haplotypes were identified in the four populations. Hyplotype diversity was high in all populations. The haplotype diversity of Mtwara and Zanzibar populations were the highest (1.000 ± 0.010) while the Dar es-Salaam and Tanga populations had the lowest haplotype diversity of 0.993 ± 0.021 and 0.992 ± 0.012, respectively. The Tanga population had the highest nucleotide diversity (0.078 ± 0.018), followed by Zanzibar (0.027 ± 0.014), Mtwara (0.025 ± 0.014) and Dar es Salaam populations (0.016 ± 0.009). Results from AMOVA indicated that variation within the populations was higher (90.35%) than the variation among populations (9.64%). According to the results for F ST , genetic differentiation between populations was greatest between Tanga and Dar es Salaam (0.17828), followed by Tanga and Zanzibar (0.14633) and Tanga and Mtwara populations (0.13865). The genetic distance between the Dar es Salaam population and the Tanga population was the highest (0.01001), followed by the genetic distance between Tanga and Zanzibar populations (0.00873) and Tanga and Mtwara (0.00827), while the genetic distance between Mtwara and Zanzibar was the lowest (0.0004). The results for the rate of migration among the populations showed high gene flow as revealed by the number of immigrants per generation. Gene flow between Mtwara and Zanzibar populations showed the highest number of immigrants (Nm = 18.31), followed by Dar es Salaam and Zanzibar populations (Nm = 15.83), while the lowest number of immigrants was found between Tanga and Dar es Salaam populations (Nm = 1.18), between Tanga and Zanzibar populations (Nm = 1.47) and between Tanga and Mtwara (Nm = 1.55). The phylogenetic tree reconstructed based on the 88 haplotypes grouped the haplotypes into two major clusters. Cluster 1 consisted of nine haplotypes, of which eight were solely from the Tanga population and one from reference sequences of Euthynnus affinis (Kawakawa tuna). Cluster 2 included haplotypes from Dar es Salaam, Mtwara, Tanga, and Zanzibar populations. There were no population-specific sub-clusters. Population history was assessed using Fu’s Fs and Tajima’s D, and the results indicated negative values. Population expansion of A. thazard was suggested based on the results of neutrality tests. In the second study, data from 4906 tons of frigate tuna were obtained from the Ministry of Livestock and Fisheries and used to assess the population trend in the four localities for the period from 2015 to 2019. The data were further subjected to ANOVA to test the significance of the difference in catches among years and locations. Over a five-year period, a total of eight species of tuna, namely Auxis thazard, Euthynus affins, Istiompax indica, Rachcentron canadum, Rastrelliger kanagurta, Scomberomorus plurilineatus, Thunnus obesus, and Xiphias gladius, were caught in the study locations. The quantity of catch differed among species (p = 0.001), whereby Rastrelliger kanagurta was the most caught species (13,473 tons for the period of five years), followed by Scomberomorus plurilineatus (7,489 tons for five years). In the case of A. thazard, the average mean catch over a five-year period was 981.16 t, contributing 19.99% of the total tuna species caught. The catch was higher in 2015 than in any other year afterward in all localities. A total of 240 frigate tuna (48 fish from each site) were collected from fishermen and measured for total body length (in cm) and body weight (in g) to assess the size of fish caught. The total length ranged from 36 to 38.0 cm, while the body weight ranged from 461 to 1612 g. The fish from Mtwara had the smallest mean body weight (792.284 ± 33.092 g) while those from Dar es Salaam had the largest mean weight (977.692 ± 25.841 g). It is concluded that there is high within population genetic diversity, but the genetic differentiation of frigate tuna populations is not significant among the four sites, hence, they can be regarded as a single stock unit for management purposes. Also, the production trend of A. thazard showed a decreasing trend over the five year period from 2015 to 2019 and the relationship between body length and weight was linear and positive. The length and weight of A. thazard exhibited isometric growth by which fish grow in weight as length increases, and the condition factors were > 1 in all sampling sites. The condition factor greater or equal to one is good, indicating a good level of feeding, and proper environmental condition.
Assessment of genetic purity and diversity of farmed tilapia fish in Tanzania mainland
(Sokoine University of Agriculture, 2021) Shabani, Mashaka
Fish farming in Tanzania is done in ponds and cages by commercial and smallholder farmers, mostly using tilapia species. The productivity of fish farming is believed to be strongly influenced by the quality of the strain cultured. In Tanzania tilapia culture is mainly dominated by Oreochromis and Coptodon spp, and most authorities consider the fast-growing Oreochromis niloticus to be the most appropriate species for aquaculture in various parts of the country. However, there other species that are farmed in some areas such as Oreochromis urolepis and Oreochromis leucostictus. These species are known to hybridise with Oreochromis niloticus. This study assessed the purity and genetic diversity of tilapia fish in hatcheries and farms in Tanzania Mainland. The study focused on three specific objectives which were; i) assessment of sources of tilapia broodstocks and fingerlings in hatcheries and farms, ii) identification of farmed tilapia fish species and hybrids using single nucleotide polymorphism (SNPs) and iii) assessment of within-and between-population genetic diversity of Nile tilapia broodstock in hatcheries and farms. Information on the sources of tilapia broodstock and fingerlings in hatcheries and farms in Tanzania Mainland was collected through face-to-face interview using structured questionnaires. A total of 248 and 16 respondents from fish farms and hatcheries, respectively, were interviewed. Data on sources of tilapia broodstock and fingerlings were analyzed using Statistical Package for Social Sciences (SPSS.Version, 21) to derive descriptive and inferential statistics. Significant differences were judged at a probability level of p ≤ 0.05. Tilapia species and hybrids cultured in hatcheries and farms were determined through SNP analysis. Species identification was facilitated by inclusion of reference samples of Oreochromis niloticus and O. leucostictus from Lake Albert in Uganda and O. urolepis from the lower Wami River in Tanzania in the analysis. A total of 536 tilapia pectoral fin samples were collected from 10 fish hatcheries and 59 fish farms3 located in seven agro-ecological zones of Tanzania Mainland. Following euthanasia, clips of the pectoral fin were cut and placed into labelled vials containing 95% ethanol. The vials were put in a cool box packed with ice and transported to a laboratory where they were stored at -20 o C, until DNA extraction. Overall, analysis was carried out on 190 fin clips, which were selected from the initial collection of 536 tilapia specimens. DNA extraction from fin clips was done using the BioArk extraction kit and SNP genotyping was performed by LGC Genomics GmbH campany in Berlin. The SNP assay was originally calibrated with three species of Oreochromis (O. niloticus, O. urolepis and O. leucostictus), not with Coptodon. A pseudo-reference set for Coptodon was generated using four specimens for which clear photographs of Coptodon were available. These were then coded as reference samples and used to identify the genotypic profile of Coptodons in the analysis, in an attempt to identify Coptodon specimens among the non- photographed samples. Principal component analysis (PCA) was done using SNPRelate package in R v4.01 software and used to preliminary identify the species and hybrids present in the collected tilapia samples. Ancestry analysis was done using Admixture v1.3.0 software to determine the proportion of ancestral admixture for assigning appropriately the different types of species and their hybrid present in both fish hatcheries and farms. A threshold of 80% cluster membership was used to classify samples as pure species. Individuals with cluster membership of less than 80% were considered to be potential hybrids. Based on cluster membership criterion, a total of 50 O. niloticus were identified out of 190 genotyped samples, whereby 31 and 19 O. niloticus individuals were from fish hatcheries and farms, respectively. These were then selected as samples for the study of assessment of within and between population genetic diversity of Nile tilapia broodstocks in hatcheries and farms. The population structure of the fish samples was analyzed using Structure v.2.3.4 Software with K values ranging from 2 to 5. Markov4 Chain Monte Carlo (MCMC) of 100 000 iterations with a burn-in period of 10 000 was carried out for each K value. Observed (Ho) and expected (He) heterozygosity parameters were used to assess the within population genetic diversity for the hatchery populations. Similarly average individual inbreeding coefficient (F IS ) for O. niloticus identified in fish hatcheries were estimated using stacks v2 software. The R package StAMPP was used to perform Analysis of Molecular Variance (AMOVA) using 1 000 permutations. Also, the principal component analysis (PCA) was carried out using the R package Adegenet version 2.1.1. The results on sources of tilapia fingerlings and broodstock indicate that, the main sources of tilapia broodstocks in fish hatcheries were other hatcheries within the country (45.5%). However, some fish hatchery managers (12.3%) were importing broodstock from Uganda and Thailand. The results revealed that fish hatcheries and natural water bodies were used as sources of fingerlings in all agro-ecological zones, but the extent of utilization differed significantly among the agro-ecological zones. Fingerlings from the wild were more utilized in the Northern, Western and Lake Zones while the use of fingerlings from hatcheries predominated in the Eastern zone. The results on tilapia fish species and hybrid identification in fish farms and hatcheries, indicate that 91.52% of the fish farms and 70% of the hatcheries were not culturing pure O. niloticus, but hybrids or tilapia of other species. The pure O. niloticus (percentage of pure individuals in brackets) were observed at Ruvu fish farm (12.90%), Safina bigfish (12.90%) and 821KJ-Bulamba (51.61%). Likewise the results for within and between population genetic diversity of Nile tilapia broodstocks in hatcheries and farms indicated that pairwise F ST values varied from 0.072 to 0.359 in some of fish hatcheries. The lowest F ST values were found between 821KJ- Bulamba and populations from Mwamapuli, Ruvu fish farm, and Safina bigfish. The highest F ST values were observed between 821KJ-Bulamba and Faiza fish farm. Admixture was detected at Mwamapuli, Faiza fish farm, Ruvu fish farm and Safina5 bigfish, but was not detected at 821KJ-Bulamba. In fish farms admixture was detected at SUA-Morogoro and Babati populations. Result on Analysis of molecular variance (AMOVA) show that 17.71% of genetic variation was found among populations, -7.69% among individuals within populations and 89.98% of variation was within individuals. Principal component analysis indicated one genetic group of O. niloticus clustering to O. niloticus reference with no any individual clustering with either O. urolepsi reference or O. leucostictus reference. This study concluded that, the main sources of tilapia broodstock for fingerlings production in hatcheries are other hatcheries within and outside Tanzania as well as wild sources. The main sources of tilapia fingerlings for stocking fish farms in Tanzania mainland are hatcheries within Tanzania, wild sources and recruits from other fish farms. A large number of sampled fish farms (91.52%) and hatcheries (70%) do not culture pure Oreochromis niloticus, instead they culture hybrids and a mixture of either Oreochromis niloticus with other species of tilapia or unknown tilapia species. There is high number of hybrid individuals both in fish farms and hatcheries than any pure single species. The high level of genetic impurity in farmed tilapia fish in both hatcheries and farms is contributed by existence of O. leucostictus, O. jipe, and O. urolepsi and Coptodon species. There is high genetic diversity within populations than among Nile tilapia populations. Based on the findings of this study it is recommended to establish certified hatcheries in each agro-ecological zone to increase accessibility of quality seeds. Also it is recommended to establish a practical tilapia breeding program for maintaining the purity of different tilapia strains as well as conducting regular training to fish farmers and hatchery managers on how to handle and manage tilapia broodstock.
Assessment of improvement of chemically and biologically treated maize stover and subsquent utilization of treated materials for beef production
(Sokoine University of Agriculture, 2016) Mushi, P. V.
Two studies were conducted to evaluate effectiveness of CaO, enzymes, microbes and Ca(OH)2 in improving the feeding value of maize stover (MS) for beef animals. Study I involved five treatments; untreated MS (T1), CaO treated MS (T2), CaO + enzymes treated MS (T3), CaO + microbes treated MS (T4), CaO + enzymes + microbes treated MS (T5). Study II involved untreated MS (T6) and MS treated with Ca (OH)2 (T7). The treatments were evaluated for chemical composition, degradability, gas production, digestibility and animal performance. Differently treated MS were fed to 80 steers and 32 steers in study I and II respectively. There was increase in CP, CF, ash and calcium while NDF was reduced in treated MS. Disappearance values at 48hrs ranged 40 to 51% units for dry matter (DM) and 40 to 47% units for organic matter (OM). The `a’ values for DM and OM degradability were 3.17% and 9.44%, 1.02% and 4.71% in untreated and treated MS respectively while the `c’ value was 0.012%/h and 0.02%/h, for treated and for untreated MS. Gas production values at 24hrs ranged 22 to 35 ml/g DM. The `b’ values were 36.2% in untreated and 42.54% for treated MS. T3 had the highest In vitro organic matter digestibility (OMD) (55%) while T5 had the lowest (48.2%). T1 had the highest Metabolizable Energy (ME) (7.2 MJ/kg DM) while T4 had lowest (5 MJ/kg DM). Dry matter intake, final body weight and average daily gain were higher for T1 and T6 than T2, T3, T4, T5 and T7. The steers on T7 had higher DM digestibility (70.2%) than those on T6 (55.7%). It is concluded that the lime treatment was effective in solubilizing the cell wall constituents and improve the digestibility of MS but had a negative effect on intake and body weight gain.
Assessment of levels and effects of selected heavy metals onimmunityof wild fish in Kafue river, Zambia
(Sokoine University of Agriculture, 2018) Chimba, N.
The current study aimed at establishing the levels and effects of heavy metals on immunity of fish in the Kafue River basin. The heavy metals analysed in fish muscle and soil included Copper, Zinc, Cobalt, Nickel, Chromium, Lead, Iron, Cadmium and Manganese using Atomic Emission Spectrophotometer. The study found the concentrations of heavy metals to be lower than set standards by FAO and WHO with Copper being the only metal showing significant differences between the sexes (p=0.009). There was a significantly lower level of Copper in fish muscle of fish (> 150g) that was collected upstream of the Copperbelt mining area. The study shows that Copper accumulation is dependent on size, weight, sex and species of fish. Heavy metal concentrations in soil were comparable between sites. However, Copper and Iron indicated higher concentrations (65.1±0.283 and 283.70±1.74 respectively) than WHO/FAO thresholds for agricultural soils. Multiple regression for lysozyme in kidney against sex and Copper was statistically significantly predicted lysozyme levels, F (2, 51) = 3.54, p< .0365, R2 = 0.12. p<0.05. The results show a significant interaction between lysozyme activity, sex of fish and Copper. A significantly higher (P<0.0028) condition factor was observed downstream the mining area indicating wellbeing of fish with the Chipata site (within the Copperbelt mining area) having the least coefficient of condition which could be attributed to metal contamination at the site. The haemoglobin concentrations were also reduced showing signs of anaemia and an increase in WBC was also indicated. A significant decline in RBC count was also detected at Mitunda site which may be attributed to various environmental effects but further studies would be needed to link this with heavy metal toxicity.
Assessment of presence of Oestrogen E1, E2 and EE2 in Lake Kariba, Zambia
(Sokoine University of Agriculture, 2017) Njobvu, L.
Oestrogens are hormones, naturally produced by mammals or synthetically produced as drugs used in hormone therapy or as contraceptives. In the recent past years, oestrogens have gained much recognition due to their detrimental effect to aquatic life, which ranges from induction of intersexuality to complete reproductive failure of fish. Their main source in the aquatic environment is attributed to human and livestock waste and residues of oestrogens are found in water downstream of waste water treatment plants (WWTP). As such, this research sought to investigate the presence of these hormones in Lake Kariba as well as identify the anthropogenic activities leading to their introduction. A structured questionnaire, was administered in order to identify anthropogenic activities that would lead to oestrogen introduction in Lake Kariba. Siavonga’s harsh terrain precludes its involvement in intensive animal husbandry activities thereby leaving only human wastewater as the main source of oestrogens in the lake. The synthetic hormone 17α-ethinyl estradiol (EE2) was undetected in all of the samples collected evidently due to low usage of oestrogen containing contraceptives and high usage of pit latrines in the area. On the contrary, natural oestrogens were detected in all sites in the range of 0.38 ng/L to 6.68ng/L in water samples and 0.01 ng/g to 2.74 ng/g in sediment samples. Source of the detected oestrogens could be a result of waste water discharge into the lake as well from terrestrial and aquatic animals. Further investigations are required to identify other sources of oestrogen introductions in sparsely populated areas that recorded oestrogen levels as high as sites receiving waste water as well as the biological effects in aquatic animals.
Assessment of production performance and market chains of village chickens in Meru district
(Sokoine University of Agriculture, 2011) Wilson, Ng’wiza Martha
This study was conducted in Meru District, Arusha region. Specifically, the study assessed production performance of VCs; identified market chains and market opportunities; analyzed gross market margins and profit margins at different stages in the market chains. Data were collected from 90 farmers, 78 traders and 33 consumers, who were purposively sampled. Production performance of VCs was computed through descriptive statistics and cross tabulations. Results that indicated the mean eggs laid per hen during dry and wet seasons were 17.0 ± 0.5 and 12.9 ± 0.4 respectively. This difference was statistically significant (p < 0.05). Survival rates of chicks 8 – 10 weeks of age were 70.9% during dry season and 67.5% during wet season. Adult’s survival rates were 87.4% and 86.1% during wet and dry season respectively. Chick mortalities were due to diseases and predators. Most farmers vaccinated their flocks against Newcastle disease. Market opportunities were identified. Marketing and profit margins were found to vary among different actors along the market chain. The results obtained indicated farmers were adequately rewarded in cocks, hens and eggs but not for growers. Hotels, restaurants/bars obtained higher marketing margins. Consumers were constrained by high price during high price seasons. The study revealed that performance of VCs was good in terms of: average age at first lay (5.7 ± 1.8 months old), hatchability percent, and adult survival rates. However, performances of VCs were poor in terms of: the number of egg laid per hen per clutch, number of clutches per hen per year, and poor performance in chick survival rates. To sustain and improve productivity it is thus recommended that special support should be provided to enable poor rural VCs producers to expand their production.
Assessment of reproductive performance of smallholder dairy cattle in Rungwe district, Tanzania and possible interventions
(Sokoine University of Agriculture, 2006) Gimbi, A A
A study was conducted aimed at establishing causes for suboptimal reproductive performance in smallholder dairy cattle and investigate on possible interventions. Experiment 1 was carried out to identify management, productive and reproductive status of the animals. The data were analysed using descriptive and Chi-square test. Monitoring was done (Experiment 2) to evaluate nutritional, productive and reproductive status of animals. Body weight (BWT), body condition score (BCS), plasma urea nitrogen (PUN), calcium (Ca), phosphorus (P) and copper (Cu) were determined. Several reproductive performance indices were calculated and association between them and the nutritional parameters were determined by Pearson’s correlation coefficients. Effect of supplementation on productive and reproductive performance was evaluated (Experiment 3) using similar parameters as in experiment 2. General linear model was applied for analysis of variance of variables in experiments 2 and 3. Chi-square test was used to determine the relationship between proportions of animals in categories of reproductive parameters and diseases in different seasons and treatment groups. Experiment 1 showed that most respondents practised zero grazing, bred animals by natural mating and dried cows 1-3 months precalving without steaming up. On average farmers fed 1.9 kg of concentrate per day for 19.2 days in a month with 23.8 g/day of minerals included in 13.7 days in a month. The observed (Means ± SD) ages at puberty, first mating, first calving (AFC) and CI were 20.5±1.0, 21.5±1.8,30.8±1.8 months and 526±123 days, respectively. In experiment 2, BWT and BCS (Means ± SEM) were 320.8 ± 3.9 kg and 2.2 ± 0.0, respectively. Concentrations (Means ± SEM) of PUN, plasma Ca, P and Cu were 8.4 ± 0.2, 7.7 ± 0.1, 4.3 ±0.1 mg/dl and 0.44 ± 0.01 pg/ml, respectively. Ovarian cyclicity resumed before 90 days postpartum in 29.4% of the animals and days to first visual oestrus (DPO) were 178.7 ±19.6 (Mean ± SEM) with 22.9% of cows showing visual oestrus before 90 days postpartum. Mean (Mean ± SEM) SC and CI were 1.5 ± 1.2 and 485.7 ± 20.1 days, respectively. The DPO was significantly correlated with BWT (r = -0.315; P<0.05), BCS (r = -0.424; P<0.01) and body condition score at calving (BCSC) (r — -0.348; P<0.05) while CI was significantly correlated with BCS (r = -0.394; P<0.05). Supplementation significantly (P<0.05) reduced DPO by 43.6 days and significantly (P<0.001) improved BWT, BCS, PUN, and milk yield by 37.9 kg, 0.3, 2.2 mg/dl, and 2.5 L/day, respectively. In addition, supplementation significantly (P<0.05) increased BCSC, plasma P, Cu, and calf birth weight by 0.4, 0.6 mg/dl, 0.07 pg/ml, and 2.6 kg respectively. Reproductive performance of the cattle was suboptimal and was attributed to nutritional deficiencies. Concentrate supplementation and body condition scoring were recommended but further research is needed to refine the feeding strategy in relation to plasma P and Cu and to establish the optimum body condition score for daily cattle production and reproduction in the area. More research is also needed to identify risk factors that contribute to cattle dystocia in Rungwe district.
Assessment of sheep production status in nkasi district, Rukwa region
(Sokoine university of Agriculture., 2011) Kapongo, Reuben Yohana
This study was conducted in two divisions namely Namanyere and Mkwamba of Nkasi district in Rukwa region in order to assess sheep production status for smallholder farmers. Eight wards namely Namanyere, Mtenga, Chala, Swaila, Kipande, Sintali, Kate and Isale were surveyed from November 2010 to April 2011. The random sampling technique was adopted to get 20 respondents from each of the selected wards. This means two villages from each ward were chosen randomly whereby in each village 10 respondents were interviewed. A structured questionnaire was used to collect data from smallholder farmers keeping sheep and was complimented by secondary data from the district council offices. The results showed that sheep strains mostly kept by smallholder farmers were variant crosses of local strains and Red Maasai. The strains were deemed to be tolerant to diseases/parasites, heat, drought and had better carcass. Extensive grazing system was adopted by most of smallholder farmers both during dry and wet seasons. Breeding was uncontrolled however, rams were selected basing on their body sizes, conformation and performance (e.g. number of lambs per ewe’s life time, age at first lambing and lambing intervals). Traits such as disease tolerance, drought and heat tolerance scored higher for most strains. Average age at first lambing was 6.5 months, the lambing interval was 3 months and the average number of lambs per ewe’s lifetime was 14 lambs. The constraints to sheep production mostly were poor market availability, endemic diseases and mortality of lambs. On marketing, fewer sheep were sold in the market compared to goats and the price was 22% lower than that of goats.
Assessment of technology adoption for free range local chicken improvement in Mzumbe ward Mvomero district Morogoro
(Sokoine University of Agriculture, 2011) Masha, Emmanuel Mbonea
The assessment of technology adoption for free range local chicken improvement was carried out using a sample of one hundred and twenty (120) farmers, fifty trained farmers, fifty neighbouring farmers and twenty control farmers. A structured questionnaire was used. Other data were obtained by direct measurement of eggs and adult live birds. Multiple Range Test (MRT) was used to separate the means especially for the production data. Results indicated that adoption rate among the trained farmers were high, being 92%, 88%, 92% and 56% in use of supplementary feeds, disease control, chick management and improved housing respectively. As for neighbours the values were 60%, 68%, 54% and 50% respectively. Much lower adoption was observed in control group values ranging from 20-55%. Record keeping was lowly adopted by all groups. Availability` of extension services, education level and veterinary services influenced adoption rate significantly (P<0.05). Trained farmers group had significantly (P<0.001) higher values for eggs weight and (P<0.05) flock size than the other categories. Male and female adult bird weights were significantly (P<0.001) higher for trained farmers than untrained farmers. Mature laying hens in the flock increased from 16% to 40%. Eggs laid/hen/cycle increased from 8- 15 to 15-25, chicks hatched/hen/cycle increased from 9-12 to 10-16, chick mortality was reduced from 65% to 30%, while grower mortality was reduced from 50% to 20%. It is concluded that, relatively simple interventions such as feed supplementation, disease control and housing, in small-scale free range local chicken production, may significantly improve their production within a relatively short period of about 1-2 years.
Assessment of the effectiveness of rumen liquor from slaughtered cattle as inoculum for estimation of in Vitro digestibility
(Sokoine University of Agriculture, 2016) Mpemba, Charles
A study was conducted to validate the use of rumen liquor from slaughtered cattle as an alternative source of inoculum for estimation of in vitro digestibility of ruminant feedstuffs. The experiments were conducted in three (3) different institutions, namely Sokoine University of Agriculture (SUA), Tanzania, National Livestock Resources Research Institute (NALIRRI) Uganda and Rwanda Agricultural Board (RAB) in Rwanda. Each institution evaluated 4 diets of different nutritional quality. The dry matter digestibility (DMD) and organic matter digestibility (OMD) of the diets were determined using in vivo total collection method and in vitro two stage technique of Tilley and Terry (1963). The in vivo experiment was conducted using four rumen fistulated steers which were allocated to the 4 diets for 4 periods in a 4 x 4 Latin square design. The in vitro technique followed 2 x 4 factorial arrangement in which the 4 diets were incubated in 2 different sources of rumen liquor; that is rumen liquor collected from fistulated and from slaughtered cattle. The obtained in vitro results using rumen liquor from fistulated and slaughtered cattle from all institutions were regressed against those determined by in vivo technique to derive prediction equations. The rumen liquor collected from the experimental animals at SUA was assessed for pH and concentrations of ammonia nitrogen (NH3-N) and total volatile fatty acids (VFAs). The pH value (6.59±0.06) of the rumen liquor from fistulated cattle was not different (P > 0.05) from that of slaughtered cattle (6.53±0.06). Rumen liquor from slaughtered cattle contained higher (P < 0.05) concentration of rumen NH3-N (122.74 ± 1.71 versus 111.34 ± 1.71 mg/l) and total VFAs (151.84 ± 7.75 versus 124.04 ± 7.75 mmoles/l) than that from fistulated cattle. The in vivo DMD of the different diets at SUA ranged from 51.6% - 61.8% while in vivo OMD ranged 51.4 – 62.2% and were both significantly (P < 0.05) different. There was no significant difference (P > 0.05) on the in vivo DMD and OMD of the diets used at NALIRRI. The in vivo DMD of the diets used at RAB ranged from 84.7% - 90.5% and in vivo OMD ranged from 82.1% - 87.9% and they were both significantly (P < 0.05) different and relatively higher than the values obtained from the other institutions. The in vivo DMD and OMD of the diets in all institutions were significantly (P < 0.05) higher than the in vitro values obtained using rumen liquor from fistulated and slaughtered cattle. The in vitro DMD (42.6%) and OMD (38.8%) obtained using rumen liquor from slaughtered cattle at SUA were significantly (P < 0.05) higher than those obtained using rumen liquor from fistulated cattle (DMD = 40.0% and OMD = 36.2%). In the other institutions, there was no significant difference on the values of in vitro DMD and OMD obtained using rumen liquor from the two sources. There was also no significant difference (P > 0.05) on the prediction equations when rumen liquor from fistulated or slaughtered cattle is used in in vitro technique for predicting in vivo DMD and OMD. From this study it is concluded that, rumen liquor from slaughtered cattle may be used for estimating in vitro digestibility of ruminant feedstuffs.
Assessment of the extent of utilizing crop residues as ruminant feed in crop – livestock farming systems in Babati district, Tanzania
(Sokoine University of Agriculture, 2017) Alphonce, H. I.
Two experiments were conducted in Babati district to assess types and quality of crop residues and other feed resources available for feeding livestock, crop residue handling, quantity fed, milk yield and manure handling and use within the farming system. Experiment one covered three different villages across different agro-ecological zones, involving 143 farmers in six focused group discussion and 54 farmers in individual quantitative questionnaire while experiment two involved 24 farms. It was observed that 0.52 to 8.25Mt./Ha of different crop residues were produced annually. About 14.6% of the crop residues were included in the animals’ diet yearly, hence contribute 1.44%, 1.36% and 1.63% of Dry matter (DM), Metabolizable energy (ME) and Crude protein (CP), respectively in the diet. All the respondents used maize stover to feed animals, while 81.5% used beans haulms and 59.3% fed pigeon pea chaffs. The average milk yield of the lactating cows under zero grazing was 11.2 kg/cow/day. The nutrient content of analyzed crop residues ranged from 4.31 to 13.9% CP and 28.8 to 65.3% In-vitro dry matter digestibility (INVDMD). Higher levels of CP were observed in leguminous than cereal crop residues. The analyzed diets from the monitored farms had a nutritive value range of 6.99 to 10.5% CP and 36.6 to 49.9% INVDMD; and the ME range of 5.69 to 8.61 MJ ME/kgDM. Considerable amounts of crop residues were available in Mid-March to May where irrigated maize was harvested and in July to October which was the major crop harvesting season. It was observed that 83.3% of household hipped manure under trees, 66.7% used manure to fertilize homestead farms and vegetable gardens while 12.5% used manure for animal beddings. It is concluded that more of the available crop residues could be used as animal feed while manure could be used for nutrient recycling, when proper technologies are impacted to farmers.
Assessment on the potential of using fish guts in broiler chicken diets
(Sokoine University of Agriculture, 2017) Juma, R. R.
The study was carried out at Fuoni Village in Magharibi ‘B’ District of Zanzibar for period of six weeks, to evaluate the potential of using fish guts in broiler chicken diets. The two hundred and forty broiler chicks were used in four dietary treatments. Each treatment contained 60 chicks which were randomly allocated into four brooding pens and each treatment was replicated 3 times with 20 chicks each. Weight of feeds and refusal were measured daily whereas chick body weight was measured once per week. The DM intake was significantly (P < 0.05) higher for the birds fed diets containing 0% and 40% fish guts during the 2nd and 5th week of age, where as no significant differences were observed during the other weeks. There was significant effect (P < 0.05) for average feed conversion ratio and it was higher for birds fed diets containing 40% and 60% fish guts. The observed body weight and average daily gain were significantly (P < 0.05) heavier in birds fed diets 0% and 20% fish guts. However, no significant differences (P > 0.05) were observed for carcass weight, dressing percentage, meat tenderness and cooking loss between the four dietary treatments. The results on the chemical composition of meat showed that there was no significant (P >0.05) effect for percentage dry matter, crude protein and ash content while ether extract was highly significant (P < 0.05) in the meat of birds fed diets containing 40% and 60% fish guts. The study revealed that feed cost was low for diets containing 60% fish guts being Tshs 649.7 per bird while gross margin of Tshs 349.5 per bird was higher than control diet. The present study showed that 20% fish guts is an optimum level to replace fish meals in broiler diets without affecting performance significantly.
Changing livelihoods and adaptive capacity of agro-pastoralists evicted from Ihefu in Tanzania
(Sokoine University of Agriculture, 2014-10-04) Msigwa, G. B.
There are numerous incidences of impoverishment and livelihood change in pastoral societies following transformation in land use and ownership and their livelihoods. Both in theory and practice, pastoral production has demonstrated flexibility in adapting to different risks. This study sought to investigate the changing livelihoods and adaptive capacity of the agro-pastoralists evicted from Ihefu Basin in Mbarali District, Tanzania. Specifically, the study sought to: (i) Examine the planning and implementation modalities of resettling pastoralists; (ii) Assess stakeholders’ perception of and attitudes towards the eviction process; (iii) Investigate what changes took place in the livelihoods of pastoralists as a result of resettlement; (iv) Examine the livelihood strategies used by agro-pastoralists to adapt to resettlement areas; and (v) Analyze the determinants of agro-pastoralists’ adaptive capacity in the resettlement areas. Structured Questionnaires, life histories, key informant interviews and focus group discussions were used to collect data from a sample of 176 respondents. The data were analyzed using the Statistical Package for Social Sciences (SPSS) computer software version 16. Descriptive and inferential analysis (Chisquare, t-test and ANOVAs and F-test) were conducted. Developed indexes were used to examine livelihood changes and adaptive capacity ofthe resettled pastoralists. The results indicated that the government and its institutions had insufficient preparation plans to accomplish pastoralists’ resettlement process. This led to the majority of resettled pastoralists having a negative attitude to the whole eviction process. The results further revealed that there were positive changes in the livelihoods majority of resettled agropastoralists. The majority of resettled agro-agro-pastoralists adopted different adaptive strategies and were able in accessing several livelihood capitals and institutional process. Such capabilities were considered to be good adaptive capacity. Availability of good iii pastures and water, different skills, culture and traditions, government and institutions The study recommends that in order to enhance the livelihoods and adaptive capacity of resettled agro-pastoralists; policy and decision-makers should revisit the planning and implementation modalities for resettling agro-pastoralists. Infrastructure such as rural roads, water supply, schools, extension and veterinary services and marketing information should be improved.