Occurrence of Escherichia coli O157 in a river used for fresh produce irrigation in Nigeria

Concerns about the persistence of Escherichia coli O157 in irrigation waters and its transmission to fresh produce makes investigation of irrigation waters imperative. The prevalence of this pathogen and seasonal levels of water quality parameters in Kubanni River were studied, using standard methods, over a 10-month period. Detection rate for E. coli O157 confirmed by slide agglutination was 2.1%. Faecal coliform counts (FCC) exceeded acceptable limits and was significantly higher in the dry season than during the rainy season (p<0.05). Remarkably, nitrate level was significantly higher in the rainy season than dry season (p<0.05). A significant (p<0.05) correlation was established between FCC and each of nitrate (r = 0.25), biochemical oxygen demand (r = 0.51) and electrical conductivity (r = 0.55). It was concluded that the Kubanni River represents a potential public health risk, being unfit for fresh produce irrigation. Perhaps, this is the first report on the isolation of E. coli O157 from water sources in Nigeria

Toxicity test and bacteriophage typing of Staphylococcus aureus isolates from food contact surfaces and foods prepared by families in Zaria, Nigeria

Strains of Staphylococcus aureus isolated from foods prepared in five families in Zaria Local Government Area were screened for enterotoxin production and phage pattern. Toxigenic strains of S. aureus were screened by the cat toxicity (emetic response), coagulase and DNase production tests and later phage typed by group I, II, III and IV phage sets at RTD (routine test dilution). Out of 44 S. aureus strains tested for enterotoxin production, 10 (22.7%) were toxigenic by the cat emetic response, 30 (68.2%) were β-haemolytic, 12 (27.3%)  α-haemolytic while 24 (54.5%) and 20 (45.5%) coagulated human and sheep plasma, respectively. All the 44 strains were DNase positive. Forty two (95.5%) were typable at RTD with 35 (83.3%) and 7 (16.7%) strong and weak lysis, respectively. Most (54.8%) of the typable strains were lysed by group III phages while a small portion 8 (19.1%) were lysed by Group IV phages. About 7 (16.7%) were of mixed phage group. Contamination of foods in the families by toxigenic strains could be said to be low, however, the prevalence of phage group III and  α-haemolytic strains of S. aureus calls for concern since these groups have frequently been implicated in food borne diseases. Effective hazard analysis critical control point (HACCP) evaluation is suggested as a means of preventing contamination of products by toxigenic strains of organisms.Keywords: Staphylococcus aureus, enterotoxin production, phage typing, haemolysis and food poisonin

The effect of the interaction of various oil types with different culture media on biomass production of Psathyrella atroumbonata Pegler

Psathyrella atroumbonata, an indigenous mushroom species, was cultured on six different media that were inoculated separately with three different grain spawns and amended with six different oils at five different rates. The results revealed that the interaction of the various oils with the different culturemedia produced a highly significant effect (p<0.01) on the dry weights and stipe and pileus diameters of P. atroumbonata. The widest mean stipe diameters were produced by the interaction of coconut x animal bedding and rice as well as butterfat x sawdust media. Both the heaviest mean dry weight and widest pileus diameters were induced by coconut x animal bedding and rice medium

The effect of the interaction of various spawn grains and oil types on carpophore dry weight, stipe length and stipe and pileus diameters of lentinus squarrosulus (mont.) singer

Lentinus squarrosulus, an indigenous Nigerian mushroom species, was cultured on six different media that were inoculated separately with three different spawn grains and amended with six different oils at five different rates. The results revealed that the interaction of the different spawn grains with the various oil types produced a highly significant effect (

Nutritional studies with Lentinus squarrosulus (Mont.) Singer and Psathyrella atroumbonata Pegler: I. Animal assay

Lentinus squarrosulus and Psathyrella atroumbonata, two edible indigenous mushroom species, were dried, ground and used in nutritional studies. According to the results L. squarrosulus and P. atroumbonata had significantly lower protein efficiency ratio (PER) values than the standard casein diet but gave rise to net protein retention (NPR) values which were at par, but slightly higher than that of the standard casein diet. In addition, the mean albumin and bilirubin levels were significant at p<0.01 while the total serum protein level was significant at p<0.05. The animals fed the protein free and P. atroumbonata diets produced comparable total serum protein levels that were significantly higher than the comparable total serum protein levels produced by the animals fed L. squarrosulus and the standard casein diet. The albumin levels produced by mice fed the protein free diet were at par with those of the P. atroumbonata diet, but significantly higher than the albumin levels of animals fed L. squarrosulus and the standard casein diets, which were similar.Keywords: Lentinus squarrosulus, P. atroumbonata protein efficiency ratio, net protein retention ratio, total serum protein, albumin, bilirubi

Energy intake and anthropometry: A case study of families in Zaria, Nigeria

Energy intake and nutritional status of 44 members of 5 families in Zaria Local Government Area of Kaduna State were evaluated for 6 consecutive days. The socioeconomic activities and health condition of the participants was determined by the administration of questionnaire interviews. Food samples were analyzed by the standard AOAC methods to determine their energy and proximate composition while nutritional status was determined by anthropometric measurements. The mean energy intake (EI) of the subjects from the families were 2435-4558 kj/d for age groups 1-5 years; 4446-4996 kj/d for age groups 6-15 years; 5632-6493 kj/d for age groups 16-35 years and; 5547-10,883 kj/d for age groups 36 years and above. Fifteen (42.9%) of the subjects from the families had a normal body mass index (BMI) of 20-25 kg/m2, 10 (28.6%) were underweight with BMI of 18.4 kg/m2 and below while 5 (14.3%) were of thin weight with BMI of 18.5-19.49 kg/m2. Energy intake contributed approximately 22% (r = 0.22) to the BMI

Study of the bacteriological and physicochemical indicators of pollution of surface waters in Zaria, Nigeria

This study investigates the pollution level of surface waters in Zaria, Nigeria. The bacteriological and physicochemical analyses performed were in accordance with standard procedures. Out of 228 samples from different sites, 128 (56.1%) had counts higher than the standards. Samaru stream was themost polluted. The frequency of contamination of samples with Escherichia coli O157 was only 2.2%. There was a positive correlation between faecal coliform count with most of the physicochemical parameters. The use of the surface waters as raw water for drinking, irrigation of food crops for rawconsumption and for recreational activities may be hazardous. The study therefore, stresses on the need to control the faecal pollution of the bodies of water

Applications of Laboratory Technology in the Evaluation of the Risk of Rabies Transmissions by Biting Dogs and Cats

While rabies is not a common disease in domestic animal species of the United States, potential exposures to rabies in the form of bites are very common and increasing. A nationwide study conducted among general hospitals shows that 1 percent of emergency room visits are for animal bites, of which 80-90 percent are inflicted by the dog (Callaham 1980). This figure is conservative, as the study did not include pediatric hospitals, the bite of victims that progress only to a physician\u27s office, or those that receive no medical care at all. In Missouri alone, this study would infer about 1500 dog bites per year reaching only the general hospital. The number of dog and other animal bites across the country is unknown but may safely be assumed to be staggering in magnitude