Prevalence and antimicrobial resistance pattern of Salmonella in animal feed produced in Namibia.

The occurrence of Salmonella is a global challenge in the public health and food production sectors. Our study investigated the prevalence, serovar and antimicrobial susceptibility of strains of Salmonella serovars isolated from animal feed (meat-and-bone and blood meal) samples from two commercial abattoirs in Namibia. A total of 650 samples (n=650) were examined for the presence of Salmonella.

Control of tick populations by spraying Metarhizium anisopliae conidia on cattle under field conditions.

Conidia of the entomopathogenic fungus, Metarhizium anisopliae, in oil/water formulation (1 × 10(8) conidia/ml) were sprayed at 3 weekly intervals on Rhipicephalus evertsi evertsi and Rhipicephalus (Boophilus) decoloratus ticks while feeding on Afrikana bulls grazing in paddocks for a period of 1 year. The fungus reduced the on-host tick populations by 83% 3 month after commencement of the experiment. The formulation by itself had only minimal effect on the tick population.

Protection of Metarhizium anisopliae conidia from ultra-violet radiation and their pathogenicity to Rhipicephalus evertsi evertsi ticks.

Metarhizium anisopliae conidia were formulated in water or in olive oil containing 3% commercial sunscreens (Everysun or E45 Sun Block 50) and exposed to an artificial UV source for up to 5 hours. Survival of conidia after 5 h of exposure to UV in oil formulation was 29% when protected with Everysun, 40% when protected with E45, and 4% in control. In comparison, survival of conidia formulated in water was 13% when protected with Everysun, 24% when protected with E45, and 0% in control.

Biological differences within Rhipicephalus appendiculatus Neumann (Acari: Ixodidae populations in Kenya.

Differences in biological parameters of Rhipicephalus appendiculatus Neumann, the brown ear tick, were investigated. They included engorgement weight of larvae, nymphs and females, fecundity, size of unfed females and mean larval and nymphal duration post-repletion on rabbits to completion of the moult. Ticks were collected from four geographically isolated zones in Kenya and from nymphs and females, size of unfed females and weight of egg batches per tick were noted (p < 0.

Performance of a prototype baited-trap in attracting and infecting the tick Amblyomma variegatum (Acari: Ixodidae) in field experiments.

Investigations were commenced to study the potential use of the fungi, Beauveria bassiana, Metarhizium anisopliae, and the attraction-aggregation-attachment pheromone (AAAP) for the control of Ambloyomma variegatum as an environmentally friendly technology. The objective of the study was to develop and test a device, which could be used for pheromone and carbon dioxide delivery and infection of ticks with the fungi in an attempt to control the tick populations in the vegetation. Using a pheromone-baited device treated with the fungi mixture, 79% of the ticks released were attracted and exposed to the fungi and of these, 78% died during incubation in the laboratory.