Entries on Microbiology
ABSTRACT: A total of 4650 domestic chickens, comprising 1410 cocks (30.3 %), 2550 hens (54.8 %) and 690 chicks (14.8 %), d sp ayed for sales between February and May 2008 at Eke-Awka market in Anambra State, south-eastern Nigeria were systematically examined for ectoparasites. Most of the cocks originated from the North while the hens and chicks were raised on nearby farms in Anambra and Enugu States. Overall, ectoparasites infested about 40.5 % of the chickens examined. The wing louse, Lipeurus caponis moderately infested 1935 chickens (41.61 %). The shaft louse, Menopon gallinae, extensively infested 2205 (31 90 %), while the fluff louse Gonoicotes gallinae ghtly infested 471 (7.07 %) chickens. The st ckt ght f ea, Echidnophaga ga inacea, at acked the head reg on of 3087 (69.37 %) wh e the symptoms of scaly leg mite, Knemidocoptes mutans, was observed on 1679 (27.70 %) of the birds, respect vely. Market survey revealed a depreciation of about 10 to 20 % in the selling prizes of the affected chickens, a positive indication that ectoparasites on chickens are associated with financial losses incurred by operatives of the poultry industry in Nigeria.
ABSTRACT: Experiments were conducted to determine the effects of the interactions of two environmental parameters, pH and salinity on the survival of juvenile Clarias gariepinus (4 – 12 g) under laboratory conditions. The pH values used were 3, 3.5, 4, 7 and 10 while salinity values varied thus: 0, 5 10 15 and 20 ppt in each o the pH values Three and 3 5 pH had lethal effects in all salinities. The corresponding Lt f . . 50 values obtained at 5 and 10 ppt were higher than those obtained at 0, 15 and 20 ppt. At 4 and 7 pH, mortalities occurred only in the higher salinities, 15 and 20 ppt. At 10 pH, Lt50 values at salinit es 10, 15 and 20 ppt were considerably low. The lower LT50 values i i i recorded at 3, 3.5 and 10 pH with the higher sal nity values ndicated the lethal effects of the interactions of both parameters on fish.
Mosquito control strategies adopted by the residents of two Ishiagu Communities (Okue and Ihie)were investgated. 53 households in Okue and 54 in Ihie were sampled. Simple structured questionnaires were prepared and administered. Percentages and chi square (X2) test of significance was employed in analysing the data. The result revealed that 429 % of the residents of the two communities used insecticides, 25.2% used mosquito coils, 6.5% used smoke of local herbs and 5.6% were insensitive to mosquito nuisance and careless about mosquito control. Choice of control measures by residents of the two communities were not statistically significant (P > 0.05). Occupational related preferences revealed that farmers ranked highest in the use of insecticides and coils (21.5%) each. 131% of teachers use insecticides and 37% use nettings. Statistical analysis of the occupational related choice patterns was significant (P < 005).
Octanol/water partition coefficient and bioaccumulation index of Bonny light crude oil, having a ractonal percentage composition of 81.11 saturate, 7.20 aromatcs, 2.48 ashphaltene and 9.21 residues, were studied in microcosm aquaria using a fresh water catfish Clarias agboyiensis. The partition coefficient (Kf iiii tow) of the crude oil was evaluated to be 0.74. The mean bioaccumulation values of the petroleum hydrocarbons (PHCs) in the homogenates of the whole fish, liver and kdney at intervals of 24, 72 and 120 hours were respectvely 0.845 ± 0.118, 11.0 ± 0.058 and 15.0 ± 0.064 after exposing the whole fishto sedimentand water, respectively containing 31 μg/g and 190 μg/l of the crude oil in the aquarium. The mean bioaccumulation values of petroleum hydrocarbons (PHCs) in the tissue homogenates of the exposed fish were higher than in the control (p<0.05), thus suggesing that Bonny light crude oil with Kow of 0.74 could be lipophilic.
The prevalence of caprine strongyle infections and the diagnostic efficacy of some culture media in supporting the recovery of strongyle larvae were evaluated using 840 faecal sampes collected from goats during slaughter at Maiduguri Metropolitan abattoir. Faecal examination conducted by the modfied McMaster technique revealed that outof 840 goats examined, 708 (83.8 %) shedded strongyle eggs in their faeces. The prevalence of infection was significantly (P < 005) higher among female, young and diarrhoeic goats than their corresponding male, adult and non-diarrheic counterparts. Faecal culture and larval recovery using the test tube filter paper technique revealedthat the direct culture o faecal samples without any additional culture medium supported the recovery of the largest number of nematode infecve larvae from the faeces. When this was used as a standard (100% egg hatch or 0% reduction in egg hatch), larval recovery was highest (P<0.05) from goat faeces (98.4 %) folowed respectively by sheep faeces (57.7 %), cow faeces (52.4 %), horse faeces (42.3 %) and so (18.6 %) as culture media. The results therefore indicatethe superor diagnostic quality o goat faeces as a culture medium for the recovery of infective nematode stages in goat faeces.
Tails of three groups of the Gekkonid lizard, Hemidactylus flavivirdis, were amputated (group I) orautotomized (groups II and III). The animals were exposed to 12 hours of ight and 12 hours of darkness. Ingroup I experiment, previously regenerated tails were amputated (repeated autotomyRA) with a pair of sharp scissors, after anesthetizing the animals with ice cubes, at point equivalent to three autotomy segments. The orginal planes of autotomy have been replaced by ependymal tubes and there were noblood exudates,. In group II the spinal cord at thelocal site of autotomy was carefuly removed (spinal cord removed, SCR), with dissecting instruments, for a length equal to one autotomy segment Lizards in group III served as controls (NormalLizard NL). The results show that the initiation o regeneration, the growth rate, the total length of new growth (regenerate) produced, and the total percentage replacement of the lost (amputated/autotomized) tails 30 days after excision were all signiicantly less in lizards of group II (p < 001) and insignifcantly less in group I lzards, when compared with the controls (group III). The results show that for complete regeneration of the lizard tai neural tissue must be present.
Laboratory bioassays were conducted to evaluate the pupicidal activity of neem (Azadirachta indica) seed kernel extracts (NSKE) on Aedes aegypti. The neem seed kernel powder was sequentially extracted with hexane, benzene, ethyl acetate, acetone, DMSO, 2-propanol, ethanol, methanol and dstiledwater. Ten concentratons (0.0, 0.25, 0.5, 1.0, 2.0, 4.0, 50, 10.0,15.0 and 20.0%) of the neem extracts were used for the bioassays. Each treatment was replcated five times. Twenty-laboratory strains of Aedes aegypti pupae were exposed to each concentration Pupae were not fed durng the exposure periods. Pupal mortality was assessed after 1 and 24 hoursof exposure. The results of the effects of 1h exposure indicated decreased pupicidal mortality whdecreasing extracts toxicity thus: ethyl acetate (LC i l i . i . i it . i l i l l l 50 = 0.06%) > acetone > (LC50 = 0.29%) > benzene (LC50 = 0.82%) > hexane (LC50 = 3.13%) and propanol (LC50 = 763%). No pupal mortality was observed with extracts from Dimethyl sulfoxide (DMSO), ethanol, methanol and distilled water. The results of the effect of extract for 24h exposure indicated pupicidal mortality in2-propanol (LC50 = 0.67%) and ethanol (LC50 = 1.70%). No pupcida mortality was observed wth hexane, benzene, ethyl acetate, acetone, Dimethylsulfoxide (DMSO), methano and distiled water extracts. The ability of some neem extracts to kill Aedes pupae at relativey low concentrations presents an alternative to the use of synthetic pesticides for control of mosquitoes. This techniqueis environmental friendly, biodegradable, less expensive, and locally available in mosquito endemicarea. Potentials for adoption in mosquito management programmes cannot be overemphasized.
The introduction of forage legumes into grass pastures has generally improved grazing animal production by increasing total edible biomass and nutrient profiles. An experiment was designed tostudy the performance of sheep grazing Brachiaria decumbens, Panicum maximum and Pennisetum purpureum in combination with Gliricidia sepium. Eighteen paddocks of approximately 0.03 ha were used in the tra Nine of the paddocks had Gliricidia sepium alley planted in rows 4 mapart and interplanted with 4 rows of either Brachiaria decumbens, Panicum maximum, or Pennisetum purpureum. The other nine paddocks had only the grass species withoutthe Gliricidia sepium. The paddocks were each grazed by 3 sheep. The pure grass stands without the Gliricidia sepium served as controls for the grass species in combination with Gliricidia sepium. The three grasses and their combinations within the alley plots were replicated three times.The animals weregrazed continuously for 28 days in the sub plots. Sheep grazing the Gliricidia/Panicum plot had a higher (P < 001) growth rate (38 g d-1) than those animals grazing both the Gliricidia/Bracharia (23 g d-1) and Gliricida/Pennisetum (21 g d-1) plots respectively. There was no significant difference (P > 0.05) between sheep grazing the Gliricidia/Bracharia and Gliricidia/Pennisetum plots. The total dry matter intake of sheep on the Gliricidia/Panicum plot was higher (P < 005) (1.33 kg DM d-1) than that of sheep on Gliricidia/Bracharia (0.86 kg DM d-1) and Gliricidia/Pennisetum (0.43 kg DM d-1) plots respectivey. The total biomass from the Gliricidia/Bracharia (23 t ha -1)and Gliricidia/Panicum (21 t ha -1) plots respectively were higher (P < 001) than the total biomass from the Gliricidia/Pennisetum ( 13 t ha -1) plo. These results demonstrate that grazing West African dwarf sheep in a Gliricidia sepium/Panicum maximum plot improved their growth rate during dry season when feed supplies are limited. It also underscores the poor performance of animals
Hereditary disorders of erythrocytes are common in many areas of the world, including Cameroon Limited knowledge on the consequences of high incidences of sickle haemoglobin (HbS) and glucose-6-phosphate dehydrogenase (G6PD) deficiency genes in the Cameroons might have been responsible for the haemoglobin genotype mismatched marriages among the sickle heterozygotes and drug-induced anaemia among the G6PD deficient individuals ignorantly treated wth oxidant drugs having high redox potential. The situation therefore, informed the random screening of the populace of the North West and South West populatons of Cameroon for these genes wth a view not only to reveal their current incidences and level of interaction but also to educate the people onthe consequences of these genetic defects. Our results revealed the total incidences of 32.20 % sickle and 1161 % G6PD deficiency genes. The percentage frequency of the sickle cell gene was higher in the South western (1880 %) than in the North West (1451 %) populations. The percentage incidence o G6PD deficiency was 921 % and 120 % for males and females respectvely in the North West and 10.85 % and 1.46 % for males and females respectively in the South West. The interaction was not sgnificant (P > 0.01) between G6PD deficiency and HbS for the North West and South West populatons. These genetic defects must have reached polymorphiclevels due to natural selection through survival advantage against death from malaria and consanguineous marriages.
Man often causes ecosystem changes due to activities such as agricultural clearing, rangeland grazing, urbanisation, road construction and mining (Majer and Beeston, 1996). Such activities can affect genetic diversity, species diversity and ecosystem diversity (WRI, IUCN and UNEP, 1992). Loss of biodiversity is a great problem of environmental and ecological consequences and humanity depends on biodiversity for fuel, food medicine and raw materials. The continuous removal of forests for various agricultural and industrial purposes has caused the loss and degradation of the primary tropical forests, leaving only man-made ones. This destruction causes extinction or loss of richness for those species whose habitats have been altered by man (Adebayo, 1995).
F. gigantica is a parasite of the liver and bile ducts of cattle, sheep, goats and wild ruminants in Africa and Asia. It is of great veterinary importance, causing the disease fascioliasis in cattle, accounting for considerable economic loss annually (Ukoli, 1990).
Virulence is an important property of microorganisms in relation to their pathogenicity and is defined as the capacity of the organism to invade tissues, multiply and produce toxic effects.