Helminth parasites of Synodontis nigrita at lower Niger (IDAH), Nigeria

The isolation and identification of helminth parasites of Synodontis nigrita and length–weight relationship of the fish in the lower Niger (Idah), Kogi State, Nigeria were carried out in order to describe the pattern of occurrence of the helminth and to establish the well-being of the host fish. A total of 102 randomly sampled fish were studied and three genera of helminths were recovered; 39.1, 48.7 and 12.2% respectively, and were harboured in the fish’ intestine. The three genera of helminths isolates identified include two nematodes (Capillaria and Contracaecum species), Acanthocephala (Acanthocephalus species) and Trematode (Posthodiplostomum spp.). Of the 102 fish studied, 16 were infected with 80 helminth parasite giving a prevalence rate of 15.7%. The overall mean intensity and mean abundance of helminth parasite occurrence for the sampled fish were 13.6 and 1.5, respectively. The mean standard length of the fish was 7.45 ± 2.59 cm. The need for fish seeds from the wild to be examined for the helminth parasites during culture practice and the socio-economic and human health implications of eating infected fish is also recommended.Key words: Acanthocephala, nematode, isolation, trematode, intestine

Nitrogen and weed management in transplanted tomato in the Nigerian forest-savanna transition zone

Weed infestation and inherent low soil fertility are among primary reasons for low yields of tomato in Nigeria. Field trials were carried out during the wet season of 2015 and 2016 to evaluate yield response of tomato to nitrogen (N) application and weed control methods in the forest-savanna transition zone of Abeokuta, Nigeria. Positive relationship exists between growth of weed species and increase in N application. Across the years of study, increase in N up to 90 kg/ha increased weed density by 11–25%, however, the increased N gave the transplanted tomato competitive advantage and thus enhanced weed smothering. Pre-transplant application of butachlor (50% w/v) or probaben® (metolachlor 20% w/v+prometryn 20% w/v) each at 2.0 kg a.i/ha followed by supplementary hoe weeding at 6 weeks after transplanting (WAT) significantly reduced weed density by at least 15% and increased fruit yield of tomato by at least 32%, compared to use of the pre-transplant herbicides alone, across both years of study. The greatest tomato fruit yield of 12.2 t/ha was obtained with pre-transplant application of butachlor at 2.0 kg a.i/ha followed by supplementary hoe weeding at 6 WAT, averaged for both years. In general, this study suggests that increased application of N up to 90 kg/ha, and complementary weed control by pre-transplant herbicide and hoe weeding at 6 WAT would improve yield of tomato in the forestsavanna transition zone of Nigeria

ASPECTS OF THE REPRODUCTIVE BIOLOGY OF HETEROBRANCHUS LONGIFILIS (VALENCIENNES, 1840) IN RIVER OKURA, KOGI STATE CENTRAL, NIGERIA

The reproductive biology of Heterobranchus longifilis was studied from October, 2011 to October 2012. Aspects studied include identification of gonad maturation stages, the sex ratio, breeding season and fecundity of the species. 654 samples of Heterobranchus longifilis were obtained from the local fishermen at Ofejiji. They were caught with gill net (4.5 x 4.5cm mesh size), setline with hooks of various sizes (12, 7, and 4). Samples were weighed and measured using the kitchen weighing balance and a meter rule respectively. The gonads were classified into stages I, II, III, IV, V, VI and VII. There was no significant difference in the female to male ratio (p > 0.05). There were 28 fecund females used for estimation of fecundity. Fecundity ranged from 17,001 (body weight = 625g, SL = 38.6cm) to 97,122 (body weight = 5158g, SL = 71.5cm) with mean value of 37744 ± 21648 eggs. Gonadosomatic index was observed to be highest in October with value of 2.80 ± 0.2 for female and 1.05 ± 0.1 for male. The frequency of occurrence of gonad stage VI was highest in October with value 85.7% and 74.2% for male and female respectively. In February, frequency of occurrence of gonad stage VI (15.6% for male and 16.7% for female) and mean gonadosomatic index peak were observed for female (1.2 ± 0.1) and male (0.4 ± 0.05). Monitoring the mean monthly gonadosomatic index and frequency of gonad maturation stages, spawning occurred mainly in October. The gonadosomatic index peak and presence of gonad stage VI observed in February could possibly be due to the residual left over eggs in the gonads of the species after its breeding season in October.&nbsp

HISTOLOGICAL AND HISTOCHEMICAL OBSERVATIONS ON THE REPRODUCTIVE ORGANS OF Archachatina marginata ovum (GASTROPODA: ACHATINIDAE) AT DIFFERENT REPRODUCTIVE STATES

The histological and histochemical variation in association with morphological variation in the repro-ductive system of Archachatina marginata ovum was the target of this investigation. Forty- five snails were dissected and categorized into 5 different reproductive stages (low mating, high mating, high egg, gravid and post reproductive). The reproductive tracts which include: hermaphroditic duct, albu-men gland, spermoviduct and spermatheca and the ovotestis were processed for histological and histochemical staining. There were some variations in the architecture of the reproductive organs be-tween the active (high mating, high egg and gravid) and non active stages (low mating and post repro-ductive) states. The active states were generally associated with colloidal or granular secretions. Gly-cogen and alkaline phosphatase activities were associated together throughout the epithelium of the reproductive system of A. marginata ovum and they were more strongly indicated in tissues that are intimately connected to the growth and development of gametes. It was concluded that morphological variation in the secreting glands of the reproductive system of A. marginata ovum is closely associated with changes in the functional secretory activities of the glands

Melatonin enhanced the restoration of biochemical profile in chlorambucil treated-rats: examination of after-withdrawal effects of the drug

Background: In the wake of global prevalence of different types of cancer, the widespread use of chemotherapy poses threat to the integrity of the reproductive system. Although chlorambucil (Chrm) has anti-calcinogenic action, its administration has been associated with reproductive damage. Similar to chlorambucil, melatonin has anti-cancerous effect. Moreover, the hormone is claimed to protect the reproductive tissues from the insult of different disruptors of their functionality and histoarchitecture. Therefore, the present study investigated the effects of post-administration of melatonin in Chrm treated rats, with an interest in examining the after-withdrawal effects of the drug.Methods: Forty rats of ten animals per group were used for the study which lasted for six weeks. The control group received normal saline (vehicle; 0.1 ml/day, p.o.) for six weeks, while group 2 was administered saline for three weeks and then Chrm during the subsequent three weeks. However, in groups 3 and 4, Chrm was administered during the first three weeks; thereafter, they were administered saline and melatonin respectively during the subsequent three weeks. Chrm and melatonin were administered at 0.2 and 10 mg/kg b.w./day (p.o.) respectively.Results: The administration of Chrm significantly decreased gonadotrophin releasing hormone, follicle stimulating hormone, luteinising hormone, testosterone and antioxidant enzymes, but significantly elevated pro-oxidant and pro-inflammatory markers compared to the control group. Moreover, it was accompanied with selected significant alterations of semen parameters and lipid indices. However, restoration of baseline status of testosterone, catalase, total antioxidant capacity, malondialdehyde, lactate dehydrogenase, uric acid, sperm count, and free fatty acid was simply enhanced by the withdrawal of the drug, while that of gonadotrophin releasing hormone, testosterone, semen parameters, superoxide dismutase, catalase, c-reactive protein, lactate dehydrogenase, and high density lipoprotein cholesterol was facilitated by the administration of melatonin.Conclusion: The restoration of biochemical profile after chlorambucil treatment could be enhanced by the administration of melatonin.Keywords: chlorambucil; melatonin; reproduction; toxicit

INTEGRATED GEOPHYSICAL METHODS IN THE CHARACTERIZATION OF SUBSURFACE CONDITIONS OF LAPITE DUMPSITE IN IBADAN, SOUTHWESTERN NIGERIA

Groundwater contamination within the vicinity of dumpsites has elicited public health concern in recent time. Studies have shown that contaminants may infiltrate into the groundwater through permeable soils, weathered and fractured bedrocks. Lapite village, underlain by Basement Complex rocks, hosts one of the largest and most active dumpsites in Ibadan. The dumpsite came into existence without prior hydrogeophysical evaluation of its suitability as a landfill site, especially its likely impacts on the surrounding groundwater. This study was designed to assess the suitability of the dumpsite for waste disposal by evaluating hydrogeophysical properties of rocks in the area. Geological field mapping was carried out around Lapite dumpsite to determine various rock types. Very Low Frequency-Electromagnetic (VLF-EM) measurements consisting of four transverses and sixty-one Vertical Electrical Soundings (VES, using Schlumberger array) were carried out along the 200.0 and 400.0 m of the dumpsite. Banded and migmatite gneisses were the underlying rocks in the area. The VLFEM pseudo-section showed high conductivity zones indicating the presence of fluid-filled fractures in the rocks. The VES geoelectric section revealed four layers namely, topsoil (33.6-973.7Ωm), lateritic sand (82.0-520.4Ωm), weathered layer (11.9-133.0Ωm) and fractured/fresh bedrock (387.0-3767.4Ωm) with thicknesses (m) of 0.1-2.8, 0.8-4.8, 1.2-49.2 and undeterminable respectively. The presence of fractured basement as indicated by VLF-EM pseudo-section and VES geoelectric section may act as a transmitting medium for leachate that may emanate from waste dump into the surrounding groundwater. Lapite dumpsite is located on weathered and fractured bedrocks and these may permits infiltration of contaminants into the surroundinggroundwater. Thus, the present condition of waste dumpsite is not suitable for an ideal waste dumpsite.&nbsp

Biodegradation of Wastes using Partially Purified Cellulose-Enzyme from Gut of Oryctes rhinoceros larvae from Rafia Palms in Itokin, Lagos State, Nigeria

Conversion of urban wastes to utilizable sugars is very important as a vital step towards reduction of environmental pollution. Consequently, this work was aimed at obtaining cellulase from the gut of Oryctes rhinoceros larvae from raffia palms in Itokin, Lagos State, Nigeria to evaluate its degradability potential on different plant leaves and selected plastic bottles. Cellulase from Oryctes rhinoceros larvae was partially purified by a combination of precipitation with ammonium sulphate and fractionation with gel filtration on Biogel P- 100. The cellulase degradability potential was examined on tree leaves from cashew, banana, maize, lemon, cassava, pawpaw, mango, almond and palm respectively, while the plastics were from bottles of teem,pepsi, eva, mirinda, cascade, still, coke, devana and nestle respectively. Data obtained show that the enzyme- cellulase has a specific activity of 2.38 Unit/mg with 32% yield with higher degradability potential on samples from plant origin than the materials from industrial wastes