Relationships between the Physico-chemical Water Parameters and Zooplankton Fauna of Tiga Lake, Kano, Nigeria

This study investigated the relationships between zooplankton fauna and physico-chemical water parameters of Tiga Lake, Kano, Nigeria from March 2009 to March 2011. Water transparency, pH, Cl-, SO42- and dissolved oxygen (DO) showed significant positive correlations (p<0.05) with species occurrence, while total solids (TS), total suspended solids (TSS), turbidity, NO3- and PO43- showed significant negative correlations (p<0.05) with species occurrence. There were significant positive correlations (p<0.05) between zooplankton abundance and conductivity, total alkalinity, total dissolved solids (TDS), Ca2+, Na+ and K+. The general chemical characteristics (pH, total alkalinity, conductivity and TDS) and major ions (Ca2+, Na+ and K+) were all within the permissible limits for aquatic life, and they showed direct relationships with the zooplankton fauna of the lake. Physical parameters (water transparency, turbidity, TS and TSS) and nutrient content (NO3- and PO43-) were considered to be limiting on the occurrence and distribution of zooplankton in Tiga Lake. The ecological relationship between zooplankton and physico-chemical parameters of the lake is an indication of its suitability for aquatic life.Keywords: Tiga Lake; relationship; water parameters; zooplankton faun

Diversity and response of Benthic Macroinvertebrates to Natural and Induced Environmental Stresses in Aiba Stream, Iwo, Southwestern Nigeria

Aiba stream, a tropical stream in southwestern Nigeria, was investigated on monthly basis from November 2012 to April 2013 with a view to comparing their response with the Biological Monitoring Working Party (BMWP) score system already in use in some eco-regions. The diversity and response of benthic macroinvertebartes were used in assessing the biological water quality and health status of the stream. Samples were collected from four different stations using the Kick Sampling Technique. All the specimens collected were preserved in 70% alcohol solution and later identified in the laboratory using relevant identification guides. Predatory invertebrates like water scorpions (Nepa and Rana spp.) and dragonfly nymphs (Macromia sp.) were sorted out in-situ and stored separately. Nineteen taxa of macroinvertebrates were recorded comprising three Phyla, four classes and 17 families. The overall Shannon-Weiner diversity and Margalef’s indices of the stream indicated that the stream was organically polluted, as evidenced by the presence of some pollution-tolerant macroinvertebrates (e.g. Families Stratiomyidae, Nepidae, Planorbidae, Chironomidae and Syrphidae). Although there were some similarities between the BMWP score system and the response of the benthic macroinvertebrate families to environmental stress, a disparity was also observed between the two which underscores the need to carry out intensive research in this regard and adapt a BMWP score system for regional freshwaters in the tropics

A study of the physico-chemical water quality, hydrology and zooplankton fauna of Opa Reservoir catchment area, Ile-Ife, Nigeria

This study was aimed at relating the zooplankton fauna of Opa reservoir catchment area (Rivers Obudu, Opa and Esinmirin) to their physico-chemical water parameters and some aspects of their hydrology. Basin perimeter, basin width, total length, number of streams, river order and discharge showed significant positive correlation with species occurrence, while compactness ratio showed significant positive correlation with abundance. Conductivity, total dissolved solids, biological oxygen demand (BOD5) and major ions were generally higher in the dry season than in the rainy season. On the other hand, flow velocity, discharge, total suspended solids, apparent colour, true colour, turbidity, dissolved oxygen (DO), DO saturation, phosphate and organic matter were higher in the rainy season than in the dry season. Cluster analysis indicated a strong relationship among some physico-chemical water parameters. pH, Na+, Mg2+, SO42-, DO, DO saturation, BOD5, Cu, Mn, Cr, Co, Pb, As and PO4 3- all showed significant correlation (p < 0.05) with zooplankton occurrence and/or abundance.Key words: Abundance, basin, hydrology, rivers, water parameters, species occurrence

Composition and distribution of dragonflies and damselflies (Insecta: Odonata) in Iloyin Forest, Akure, Southwestern Nigeria

Odonate fauna of Iloyin Forest was studied from October to December 2009 to have an overview of the species composition and distribution with the threat of deforestation in the area. Adult species were collected once a week using a sweep net throughout the period of the study from three study sites (denoted as I, II and III) with varying levels of anthropogenic disturbance. A total of 76 species belonging to eight families were recorded in the forest. The two most abundant families in the forest were the Libellulidae (Anisoptera) and Coenagrionidae (Zygoptera).  Palpolpeura portia, P. lucia and Congothemis dubia were the dominant species of Libellulidae, while Pseudagrion kersteni was the dominant coenagrionid.   Some species of Odonata usually associated with shaded forests were encountered in two of the study sites. The highest diversity and evenness indices were recorded at Site I, followed by Site II and the least recorded at Site III. Although shade-loving species recorded in the study area was an indication of its richness in forest Odonata, some may have however become locally endangered or extinct as a result of deforestation. A check in the rate of deforestation could preserve the few forest (endangered) species and restore the locally extinct ones that changed habitats. Key Words:     Biodiversity, Conservation, Disturbance, Forest, Freshwater, Odonat

Rapid survey of Dragonflies (Insecta: Odonata) of Kribi forest and Campo Ma'am national Park, Southern Cameroon

A five day survey was carried out to assess the odonate fauna associated with the riverine sections of two forests (Kribi Forest and Campo Ma’am National Park) of southern Cameroon. The primary objective of the study was to determine the species composition and community structure of the odonate fauna occurring in the forests. The goal is to infer the health status of the two forests. Three study sites were selected, one in each of the main water bodies in the forests (Rivers Kienke and Linde in Kribi forest, and River Bitande in Campo Ma’am National Park). All the specimens collected were identified to the lowest taxonomic level. A total of one hundred and ninety four (194) individuals of Odonata were collected in the forests comprising 10 families, 24 species of Anisoptera and 30 species of Zygoptera. Anthropogenic activities were less prevalent at Campo Ma’am National Park, an area in which all the 10 families were incidentally recorded.The community structure of the southern forest revealed that only River Bitande with Shannon-Wiener diversity index (H`) of 3.80 was having a stable environmental condition. Others were close to stable condition (River Kienke H` 2.99 and River Linde H` 2.95) with mild disturbance caused by human activity. Simpson index range (0.94 – 0.98) at the three study sites revealed that the vegetation was matured and stable. The distribution of dragonflies and damselflies revealed a stable environment (Evenness 0.90 – 0.95). Kribi Forest appears to be more impacted by anthropogenic activities as fewer (six) families were recorded there. The relative distribution of the species in the two forest ecosystems seemed to have some relationship with human interference therein. Key Words: Damselfly, Dragonfly, Diversity, Forest, Rive

Preliminary limnological survey of Ori stream, Iwo, Osun State, Nigeria

Ori stream (one of the tributaries of River Oba, Iwo, Osun State, Nigeria) was studied from October to December 2013 with the aim of providing baseline information on its water quality, phytoplankton primary productivity and invertebrate faunal composition. Plankton samples were collected by towing plankton net over a 2 metres horizontal distance, while benthic macroinvertebrate samples were collected by kick-sampling technique. Hydrological and some physico-chemical variables were  determined in-situ, and water samples collected for further physico-chemical analyses in the laboratory. A total of 17 phytoplankton species, seven species of zooplankton and eight species of benthic  macroinvertebrates were recorded. The upper reach of the stream was the most polluted with the presence of biological indicators of poor water quality, while the lower reach recorded some biological indicators of good water quality. Although the upper reach recorded the highest gross primary productivity, the highest net primary productivity was recorded at the stream’s lower reach. Water quality typically decreased from the upper  reach of the stream towards the middle reach but later picked up at the lower reach before discharging into River Oba. The physico-chemical and biotic nature of the different reaches were a reflection of human activities in and around the stream. Keywords: Benthic macroinvertebrates, conservation, headwater stream, plankton; primary productivity, water quality

Treatment Outcomes among Human Immunodeficiency Virus and Tuberculosis Co-Infected Pregnant Women in Resource Poor Settings of South-western Nigeria

The complex interactions between Human Immunodeficiency Virus (HIV) and Tuberculosis (TB) infections may be magnified, in the presence of another potentially stressful condition like pregnancy. Though co-infection among pregnant women is rare, treatment outcomes may depend on accessibility to comprehensive treatment modalities. The objective of this study is to determine treatment outcomes among pregnant HIV and TB co-infected pregnant women in Lagos, South-western Nigeria. This retrospective, analytical study was carried out among ninety four (94) eligible pregnant women co-infected with HIV and TB at selected health-care facilities in Lagos state between January, 2008 and December, 2009. A standard checklist for data collection was used and analysis was carried out using the EPI info software. Mean age of respondents was 30.8 (±3.9) years. Sixteen (17.1%) TB cases were clinically diagnosed for tuberculosis. Among tuberculosis cases identified through sputum microscopy, 60(63.8%) were acid fast bacilli (AFB) positive and 21(22.3%) were identified in the first trimester. The mean percentage adherence to anti-retroviral drugs was 95.9% (±5.3). None of the participant smoked cigarette. Seventy three {73 (77.7%)} had contact with TB infected or suspected person in the last three months. Treatment outcome in mother showed that 74(78.7%) were cured, 8(8.5%) relapsed while 12 (12.8%) had treatment failures. Among the babies, 83(88.3%) were born alive. Women with both poor adherence (<90%) and with positive TB contact, but neither factor alone, were half-fold less likely to be cured compared with women with both good adherence (>95%) and no TB contact (OR=0.59, CI=0.45-0.95 and p=0.014). Cure rate was substantially lower in this study. This calls for extra strategies such as routine TB screening in antenatal clinics, strict adherence to national guidelines in the treatment of HIV/TB co-infections, focused antenatal care and comprehensive Prevention of Mother to Child Transmission (PMTCT) care and treatment

Hydrology and water quality characteristics of a stressed lotic freshwater system in southwest Nigeria

The hydrology and water quality of Aiba stream were investigated from November 2012 to April 2013 on monthly basis. This was with a view to assessing the status of the stream sequel to its last study which indicated a poor physico-chemical water quality. Four sampling stations were established for the study along the longitudinal axis of the stream, covering both the upper and lower reaches. Hydrological input from the upstream reservoir was observed to be considerably low during the dry season, a situation which further exacerbated the water quality as indicated by very low dissolved oxygen concentration, high BOD5, high conductivity value and high ionic concentrations. High nutrient (PO43- and NO3-) level recorded in this study indicated a eutrophic freshwater system. Generally, the physico-chemical nature of the water in the dry season indicated that the stream fell short of the standards required for freshwater life. Urgent steps need to be taken to mitigate the impacts of natural and man-induced stresses on the stream in order to safeguard the ecosystem and the surrounding terrestrial ecosystems.Keywords: channel width, discharge, flow velocity, hydrological characteristics, lotic system, spatio-temporal, stress, water qualit

Haemorheological factors in diabetes mellitus patients in Obafemi Awolowo University Teaching Hospital Complex (OAUTHC), Ile-Ife, Nigeria

A study on haemorheological factors in diabetes mellitus patients was carried out. Fifty blood samples were analyzed, comprising of thirty (30) diagnosed diabetes mellitus patients attending chemical pathology Clinic in OAUTH Ile-Ife and twenty (20) from apparently health individuals. The haemorheological parameters determined in this study were Packed cell volume (PCV); Erythrocyte Sedimentation Rate (ESR), Plasma Fibrinogen Concentration (PFC), whole blood viscosity (WBV), Plasma Viscosity (PV), and plasma glucose. Microhaematocrit, the Westergren's and Ingram's (1961) methods were used respectively for analysis, while technique of Reid and Ugwu (1987) was used for whole blood and plasma viscosity. Glucose-oxidase method was used for plasma glucose estimation. The mean ± S.E.M values obtained for the patients are: PCV 39%, ESR 35mm Westergren in 1 hour, PFC 55.50g/m., WBV 6.12, PV 1.97 and glucose 7.39mmol/L while those of controls are: PCV 42.45%, ESR 6.80, PFC 31.60g/ml, WBV 3.84, PV 1.56 and glucose 3.94mmol/L. All the parameters were statistically significant (