MSUIR Collection:https://cris.library.msu.ac.zw//handle/11408/2942024-03-28T16:59:46Z2024-03-28T16:59:46ZThe effects of stocking density on the growth perfomance, survival and feed conversion ratio of nile tilapia (orechromise niloticus) fry reared in conccrete tanks.Alifa, Stanleyhttps://cris.library.msu.ac.zw//handle/11408/41382022-06-27T13:49:05Z2019-01-01T00:00:00ZTitle: The effects of stocking density on the growth perfomance, survival and feed conversion ratio of nile tilapia (orechromise niloticus) fry reared in conccrete tanks.
Authors: Alifa, Stanley
Abstract: The study was conducted to evaluate the effect of different stocking densities on growth performances, survival rate and feed conversion ratio on the production potential of Nile tilapia fry (Oreochromis niloticus) reared in concrete tanks for 30 days from 10 November to 8 December 2018 at Lake Harvest Aquaculture, Kariba. A total of 120 000 fry (0.02 ± 0.002g) were collected, weighed and stocked in 16 tanks (each of 3.2 m² size) at four stocking densities of 3000 fry/ tank (T1), 6000 fry/ tank (T2) and 9000 fry/tank (T3) and 12000 fry/tank (T4). Each stocking density was replicated four times using a completely randomized design. Fry were fed with 17α- methyl testosterone hormone mixed with formulated feed 6 times a day at an initial rate of 15% of their body weight and adjusted to 10% of their body weight towards the end of experiment. Water quality parameters were monitored and found to be within suitable range for freshwater aquaculture. At the end of trial period, One -Way (ANOVA) using SPSS was used to test for significant variations (P<0.05).There were significant differences for growth parameter across all stocking densities. All growth measures were inversely proportional to stocking density. Weight gains were 1.03 ± 0.22g, 0.92 ± 0.08g, 0.65 ± 0.36g and 0.48 ± 0.46g for T1 to T4 respectively. Daily weight gains were 0.34 ± 0.0007g, 0.30 ±0.0002g, 0.22 ±0.0012 g and 0.16 ±0.0015g from T1 to T4 respectively. Specific growth rates per day were 0.13 ± 0.0007%, 0.13 ± 0.000, 0.12 ± 0.0018% and 0.11 ± 0.0029% from T1 to T4 respectively. Survival was indirectly proportional to stocking density. The highest survival rate was 81.55% ± 0.36 in T1 and the lowest survival was 55.17% ± 1.98 in T4. Increase in FCR was directly proportional to increase in stocking density .FCR was best in T1 with mean of 1.08 ±0.22.The worst FCR was found in T4 with an average of 2.26 ± 0.19. Cost based analysis showed highest feed loss directly proportional to stocking density. The lowest feed loss was 0.82 grams in T1. Feed loss increased across all treatments to 10.23 in T4. Net profit was highest in T2 followed by T1, T3 and lowest in T4.The study concluded that stocking 6000 fry per tank is beneficial for optimum growth, survival and good feed conversion ratio and farmers can stock 6000 fry in 3.2 m² concrete tanks for beneficial and optimum production of fry.2019-01-01T00:00:00ZAlifa, StanleyIdentifications and antibiotic Susceptibility patterns of Urinary Tract infections in patients presenting at the Zvishavane District HospitalNyakunhuwa, Beloved S.https://cris.library.msu.ac.zw//handle/11408/39142022-06-27T13:49:05Z2018-06-01T00:00:00ZTitle: Identifications and antibiotic Susceptibility patterns of Urinary Tract infections in patients presenting at the Zvishavane District Hospital
Authors: Nyakunhuwa, Beloved S.
Abstract: Urinary tract infections (UTIs) are the most common type of infections encountered in medical practice today. Effective treatment of these infections is being hindered by antibiotic resistance of UTI pathogens. Prevalence of UTIs differs with geographical location, seasons, and gender. Therefore, it is important to isolate and identify the uro-pathogens causing UTIs in an area and determine their antibiotic susceptibility patterns. In this study, a total of 92 mid-stream urine samples from patients who were presenting at the Zvishavane District Hospital (ZDH), were examined for UTIs using standard microbiological techniques during the period May 2017January 2018. Of the 92 samples examined 12 (13%), comprising nine from females and three from males, were infected with UTIs. Escherichia coli was the most prevalent uro-pathogen isolated comprising 58% of the isolates, followed by Klebsiella spp (17%) while three other isolates, S. saprophyticus, S. aureus, and P.aeruginosa had the same prevalence of 8%. Chloramphenicol was the most effective antibiotic being effective against 10 out of the 12 (83%) isolated uro-pathogens, followed by Gentamicin which was effective against 8 out of 12 (67%). Fusidic acid was the least effective antibiotic because all isolates (100%) were resistant to it. Only 2 out of 12 isolates were sensitive to Nalidixic acid. Five out of 12 isolates were resistant to the drug combination of Nalidixic acid and Fusidic acid, (resistant pattern or antibiotype Nalidixic AcidR Fusidic AcidR), suggesting that, this treatment combination should not be prescribed for UTIs. Chloramphenicol and Gentamicin were equally effective against most isolates because there was no significant difference in the proportion of the isolates that were sensitive to both of them (Chisquare, p = 0.001). The take home message from this study is that the most common UTIcausing pathogen in patients presenting at ZDH was E. coli and most pathogens were resistant to Nalidixic acid and Fusidic acid but sensitive to Gentamicin and Chloramphenicol. Therefore, Gentamicin and Chloramphenicol are recommended for UTIs treatment. A relatively low prevalence of 13% suggests that UTIs are not a risk to the residents of Zvishavane.2018-06-01T00:00:00ZNyakunhuwa, Beloved S.Cadmium from sludge and effluent from Gimboki Sewage Treatment Plant accumulates in the vegetable Telfairia occidentalisHlupo, Munyaradzi Phttps://cris.library.msu.ac.zw//handle/11408/39112022-06-27T13:49:05Z2018-06-01T00:00:00ZTitle: Cadmium from sludge and effluent from Gimboki Sewage Treatment Plant accumulates in the vegetable Telfairia occidentalis
Authors: Hlupo, Munyaradzi P
Abstract: Use of sewage sludge and effluent in cultivation of crops and vegetables is a common practice in Zimbabwe. However, high concentrations of heavy metals such as Cadmium (Cd) in sewage sludge and effluent does not only result in environmental contamination, but may lead to elevated heavy metal uptake by crops, which may affect food quality and safety. The current study aimed to investigate if high concentration of Cd in sludge and effluent from Gimboki Sewage Treatment Plant translates into high concentration of Cd in the leaves of the vegetable Telfairia occidentalis. A total of 20 vegetable samples were analysed for presence of Cd using an Atomic Absorption Spectrophotometer (AAS). Telfairia occidentalis leaves grown under a combination of sludge and effluent had the highest Cd concentration of 24 ± mg kg-1, which was 100 times higher than the EEC (European Economic Commission Regulation) permissible limit of 0.2 mg kg-1. This was followed by leaves of plants grown under effluent only with 6.92 ± mg kg-1, which also exceeded EEC permissible limit by 35 times. Remarkably, T. occidentalis leaves of plants grown with neither sludge nor effluent did not have any detectable Cd concentration. It can be concluded that high concentrations of Cd in sewage effluent and sludge led to accumulation of Cd in pumpkin leaves thereby compromising the quality and safety of the vegetables for human consumption. I therefore recommend that farmers at Gimboki Sewage Treatment Plant should desist from using sludge and effluent for manuring and watering their crops.2018-06-01T00:00:00ZHlupo, Munyaradzi PAn investigation of the susceptibility of three Acacia species to Viscum articulatum infectionMandaza, Melodyhttps://cris.library.msu.ac.zw//handle/11408/37402022-06-27T13:49:05Z2019-01-01T00:00:00ZTitle: An investigation of the susceptibility of three Acacia species to Viscum articulatum infection
Authors: Mandaza, Melody
Abstract: Acacia species are indigenous trees which are of great importance in Zimbabwe. They can be used for various purposes for example making pulp and tannin, as cattle feed, as fuel (charcoal and wood) and for timber production which can be used for construction purposes. However, Acacia species are being affected by Viscum articulatum in Zimbabwe especially in Greystone Park, Mazowe district, Glen Lorne and some parts of Midlands province. At present, Acacia trees affected by the Viscum articulatum are pruned to remove all the infected parts. The removed parts are buried to control the parasite and in heavily infested cases they are cut down and burnt as a way of controlling the Viscum articulatum parasite from spreading. A study was carried out at Forestry Commission to investigate the susceptibility of three Acacia species (Acacia sieberiana, Acacia polyacantha and Acacia nilotica) to Viscum articulatum infection between mid-January 2018 and mid-February 2019. Samples of Viscum articulatum parasite were collected from Hakuna Matata Primary School and Gaydon road in Greystone park form Acacia hosts. Inoculation of parasite was done by watering with infected water and by means of air layering for a period of four months. Five seedlings of each of the three Acacia species were used. Susceptibility of the species to the infection was determined by the development of the mistletoe and growth retardation of the seedlings. It was observed that Acacia sieberiana and Acacia polyacantha showed greater retardation by the infection especially on the seedlings which were inoculated by air layering compared to watering. Acacia sieberiana which was inoculated by means of air layering developed mistletoe which grew up to a mean height of 19 µm and recorded highest proportion (100%) of seedlings showing signs of infection after a four months period. The controls, which were the untreated seedlings, were not affected. Findings from this study shows that Acacia nilotica is less susceptible to Viscum articulatum whilst Acacia sieberiana and Acacia polyacantha are susceptible, therefore growing Acacia nilotica which is less susceptible to the infection can be a method of choice as it is environmental friendly other than making use of chemicals.2019-01-01T00:00:00ZMandaza, Melody