Journal of Environmental Extension

Lambda-cyhalothrin toxicity in quails (Cortunix japonica): performance, clinicopathologic changes and effect of garlic

A.O. Omonona — Mon, 03 Oct 2016 00:00:00 +0000

The use of pesticide in modern agriculture has increased tremendously. Pesticides control harmful pests and also affect the delicate balance of the functioning ecosystem. The indicator species of wildlife, such as quails are sentinels in assessing acute and prolonged exposures to pesticides. Lambda-cyhalothrin LCT is the active agent present in many insecticides used to control agricultural pest in Nigeria. Garlic contains a variety of effective compounds needed to increase the welfare of livestock. This study investigates the impact of chronic toxicity of the natural pyrethrin (LCT) on wildlife sentinels and the ameliorative effect of garlic.

Forty quails were exposed to LCT, and to garlic for duration of 6 weeks at different ages. They were divided into 5 groups of 4 birds each according to age (6 and 8 weeks). Blood samples were analyzed using the microhaematocrit and cyanmethaemoglobin methods. Cholinesterase (AchE) was quantified as butyryl cholinesterase activity, oxidative stress markers assayed and tissue changes examined microscopically.

Clinically, there was increased pecking and the rate of food consumption of the quails increased.There was loss of plumage and an increase in faecal droppings of the quails. There was significant change in haematological parameters in the 8 week old quails (p<0.05). The 6 weeks old quails exposed to LCT showed increase in all the parameters except for the lymphocytes and eosinophil that exhibit a mild but continuous decrease. The 8 weeks old showed granulocytopenia and thrombocytopenia. The effect of garlic was also shown on the quails exposed to LCT as there was an increase in the lymphocytes and eosinophil. There was marked decrease in cholinesterase activity and an increase in malonyl aldehyde (MDA) in the LCT only exposed group (p<0.05). Microscopically, there was denudation of villi, cellular debri and infiltrates in lumen of the intestine. Pulmonary congestion and edema in air spaces of the lungs. Severe diffuse vacuolation of hepatocytes in the liver and neuronal necrosis and vascular edema in the brain.

LCT induced moderate toxicity and garlic increased cellular response in the quails. There is need for policy and research in areas of ecotoxicology and environmental pollution of pesticides with adverse consequence on wildlife conservation.

Keyword: Ecotoxicology, Lambda-cyhalothrin, Pesticides, Quails, Wildlife

Environmental and socio-economic impact of aquatic weeds on the water of Awba dam: its effect on ecotourism

Ajani Funmilola — Mon, 03 Oct 2016 00:00:00 +0000

Fresh water is mankind’s most precious resources, the increasing scarcity of clean fresh water through population growth and development, droughts, contamination, and other factors, places greater demands on the very foundation of the society. Unfortunately, invasive plants and algae are progressively disrupting the ecological balance required for maintaining adequate fresh water resources for flora, fauna, and humans. These macrophytes generally have negative impacts on tourism and recreation. This study was aimed at assessing the environmental and socio-economic impact of aquatic weeds on Awba dam and it overall effect on ecotourism.

The physico-chemical assessment of water samples of the dam was done at dry and wet season in replicates. Water samples were collected from weed infested areas and also from the control site devoid of weed, using Standard laboratory methods. Field survey was done to determine the aquatic weed species present on the dam while an interview with a staff of the maintenance unit was used to estimate the economic impact of the weed on the dam.

Result revealed that parameters such as phosphate (0.11;g/ml - 0.12;g/ml), chloride (21mg/l - 37.33mg/l), sulphate (0.13mg/l to 0.19mg/l) were higher than the required limit while nitrate (1.2 - 2.89mg/l) was below the recommended limit. Turbidity (20.6 FTU - 108.8 FTU), Total dissolved solids (114mg/l - 197.67mg/l) and Total suspended solids (207mg/l - 1559.35mg/l) were higher than the recommended limit. The pH value (2.57) for Station A was also below the recommended limit . A total of 22 species of weed were identified on Awba dam, with Eichornia crassipes and Sacerolepis africana which are of serious environmental importance, been the most dominant weed. The interview with the maintenance unit revealed that millions of naira is been expended in managing and controlling the aquatic weeds.

This study shows that aquatic weeds can permanently alter physico-chemical parameters of freshwater ecosystem if allowed to thrive over long periods. Furthermore, the study has revealed the economical challenge of these weeds to the University administration. This calls for proper management strategies in controlling the spread of these weeds if ecotourism potentials are to be fully harnessed.

Keywords: Aquatic weeds, physico-chemical parameters, water resources, recreation

Ecotourism and community development: a case study of Olumirin Waterfall, Erin – Ijesha

O.O. Ajayi, I.A. Ayodele — Mon, 03 Oct 2016 00:00:00 +0000

Ecotourism, one of the fast expanding tourism markets receiving global attention, accounts for a large share of some countries’ Gross Domestic Product; contributes to the livelihoods of many people; as well as encourages community participation and development. This study assessed the contribution of ecotourism to the community development of the host community and her environs. The survey research design relied on primary data collected through the questionnaire instrument. Tourist survey, staff survey, local business sector survey and community members’ survey were used to determine tourists appreciation, sensitivity and participation; tourists patronage; business turnover and ecotourism-related development in the community respectively. Data collected were analyzed using descriptive statistics. The survey showed that employment opportunities generated were mostly as business owners and staff on the tourist site. Over half of the respondents (fifty-five percent) and 36.67% accepted that tourist influx has a ‘good’ influence on trade and business in Erin Oke and Erin Ijesha respectively. Sixty percent and 33.33% of respondents in Erin Oke and Erin Ijesha respectively attributed the development of facilities/infrastructures to the ecotourism of Olumirin waterfall. Olumirin Waterfalls attracts high tourists’ visitation; which aids revenue generation from gate receipts as well as positively influences local trade and businesses. Contributions to the communities are however minimal; majorly in forms of small scale establishments within and outside the ecotourist destination and the few members of the community employed as members of staff. Improved development of the communities such as good road network and recreational facilities construction will increase tourist influx as well as the economic and social welfare benefits to the residents. Revenue sharing policies should also be incorporated into the management policies.

Keywords: Ecotourism, Community Development, Olumirin Waterfalls, Erin-Ijesha

Pysico-chemical parameters of the upper and lower reach of the new Calabar River, Niger Delta, Nigeria

H.E. Dienye, G.N. Woke — Mon, 03 Oct 2016 00:00:00 +0000

The physico-chemical parameters of the upper and lower reach of the New Calabar River across five stations in relation to season were investigated from December 2013 to May 2014.The result showed that the water was slightly acidic across months with pH range of 6.18to7.08 and across Stations. Relatively high Do levels were observed during the study with higher value at the upstream sampled stations than downstream sampled stations. There was no significant variation in Temperature and BOD across Stations and season. Further results revealed that there were variation in salinity values, lowest salinity was recorded in station 5(5.93mg/l) and lowest in station 2(1.08mg/l) while the highest salinity in December (6.01).Dissolved Oxygen decreased across Stations (6.45 to 4.49mg/l) but showed variation across season.

Keywords: New Calabar River, Physico-chemical parameters, seasonal variation

Parasites of cattle egrets (Bubulcus ibis) and the associated haematological and biochemical changes

A.O. Omonona, I.O. Ademola, M.O. Ogunrotimi — Mon, 03 Oct 2016 00:00:00 +0000

Parasitic diseases play an important role for wild animals and it is recognised as a significant factor in the successful conservation of endangered species. Diagnosing parasite infection and load in free-ranging populations traditionally is done via necropsy or coproscopy. Forty cattle egrets (Bubulcus ibis) were captured and used for this study. The birds were examined for parasites and associated ectoparasites were collected and identified. Gastrointestinal content of each bird was also examine for adult and eggs of different helminthes and protozoan cysts while blood smears were examined microscopically to identify the different haemoprotozoa associated with the birds. The haematological parameters and serum biochemistry profile of these birds were also evaluated.

Menopon gallinae was the only ectoparasite seen with a prevalence of 52.5%. The endoparasites observed include Ascaridia galli with the highest prevalence 14 (35%), Heterakis spp 7(17.5%), Trichostrongylus tenuis and Capillaria spp having the same prevalence 5(12.5%), Fascioloides magna 4(10%) and Syngamus trachea with 3(7.5%) had the lowest prevalence. Haemoproteus spp 9(22.5%) was the most prevalent haemoparasites observed with Leucocytozoon spp having a prevalence of 4(10%) while Plasmodium spp had the least prevalence of 3(7.5%). Eighty percent of the cattle egrets had at least one of the different endoparasites while 52.5% had ectoparasites and 40% had haemoparasites. There was a 22.5% prevalence of the combined co-infection of at least one each of the different endoparasites, ectoparasites and haemoparasites species in the cattle egrets. The risk of a co-infection of only endoparasites was found to be 20% while the infection with only ectoparasites and haemoparasite was found to be 2.5% in both cases. However, 92.5% of the cattle egrets had at least one of the different parasites while a combined infection of both Ectoparasite and endoparasite had the highest co-infection prevalence (25%). The study also showed that there was a significantly higher risk of co-infection of the different types of parasites in cattle egrets. There were significant differences in the haematological parameters and the serum biochemistry profile of the infected cattle egrets compared to the uninfected birds.

This study suggests that cattle egret when living near poultry pen could serve as a reservoir host for the transmission of parasitic diseases. Further research on parasite host interaction of wildlife birds is warranted to determine their possible role in the biological transmission of diseases.

Keyword: Wildlife, Cattle egrets, parasites, haematological parameters, serum biochemistry

Physical masculization and growth performance of Oreochromis niloticus placed on 17α-methyltestosterone treated diet

E.F. Osho, E.K. Ajani, B.O. Omitoyin, V Aniebo — Mon, 10 Jun 2024 00:00:00 +0000

Precocious reproduction of Nile tilapia still remains an impediment to its commercial culture. Various techniques have been used to solve this, including the culture of all male populations. The use of 17 α-methyl testosterone for sex reversal has been practiced but the effective dosage to maximize this technology is yet to be established for Oreochromis niloticus. This study was therefore conducted to evaluate the effect of different doses of 17 α-methyl testosterone (MT) on the sex reversal and growth performance of O. niloticus. Nile tilapia brood stocks with average weight of 220±7g were appropriately paired in happas. After two weeks, fertilized eggs were taken from the mouth of the female and hatched in jars. 300 fry were randomly stocked in 15 plastic aquarium tanks at a density of 33fish/m2, forming five treatments with three replicates. Fry feed of 45% crude protein was treated with different levels of 17 α-methyl testosterone to form five treatments (MT₀, MT₁, MT₂, MT₃, MT₄ with 0mg, 20mg, 40mg, 60mg, and 80mg of MT/kg of feed respectively) fed to the tilapia fry after yolk absorption for 28 days. Percentage Specific Growth Rate (SGR), Mean Weight Gain (MWG), survival rates, and water quality were measured. Sex determination through histological examination was done following the gonadal squash method. Descriptive analysis and ANOVA were used to analyze the data collected. Results revealed that treatment MT₃ had the highest SGR) of 7.57±0.3%, followed in descending order by treatments MT₁, MT₂, MT₀ (control), and (MT₄) with values 7.46±0.3%, 7.31%±0.2%, 7.28%±0.2% and 7.08%±0.5% respectively. The MWG (%) showed that treatment MT₃ had the highest value of 11.0±13.1% while treatments MT₄ had the least MWG of 8.2±21.5%, MT₀, MT₁ and MT₂ had 9.1%±2.8, 10.2±9.9% and 9.3±4.3% respectively. Treatment MT₃ also had the best survival rate percentage of 86.7±5.7% while the least was recorded in MT₄ with value of 70%±5.0. Treatment MT₃ with 60mg/kg of MT diet was the most efficient in sex reversal, resulting in 80±3.34% males, 20.0±7.8% intersex and no female, while MT₄, MT₁ MT₂ and MT₀ had 60±6.2% 50±4.2%, 50±6.9%, 25±2.9% respectively. Results showed that 17 α-methyl testosterone had a significant effect on the sex ratio of the fish. 60mg/Kg of MT in feed was the most effective of all the doses tested.

Keywords: Sex reversal, Monosex, Precocious reproduction, Oreochromis niloticus