Estimating the risk of exposure of British livestock to foot-and-mouth disease associated with the importation of ship and aircraft waste

A quantitative risk assessment model was developed to estimate the frequency with which meat waste from ships or aircraft might expose British livestock to infection with foot-and-mouth disease (fmd), and investigate the factors that might contribute to the risk. In the model, the total weight of waste introduced that was contaminated with fmd was estimated to be 26 kg per year, with 90 per cent certainty that it would be between 10 and 53 kg. As a result, it was estimated that there would be a mean of 1429 years between outbreaks of fmd due to ship and aircraft waste, with a 90 per cent certainty that the interval would be between 500 and 10,000 years. These estimates were affected by three principal uncertainties: first, the prevalence of fmd; secondly, the probability of the waste being removed and fed to pigs; and thirdly, the probability that overboard dumping of contaminated waste might expose livestock to fmd. The effect of these uncertainties on the model was investigated in a sensitivity analysis.     

VACCINATION OF PIGLETS AGAINST ESCHERICHIA COLI ENTERITIS

An immunisation procedure involving intraperitoneal followed by oral administration of a killed Escherichia coli vaccine was used to reduce losses associated with colibacillosis in young pigs reared under commercial conditions. Mortality was reduced in both the preweaning and postweaning period. The mortality rate among vaccinated piglets was half that of unvaccinated controls and by 3 weeks after weaning the total weight of pigs produced was 33% higher in the vaccinated group than in the control group.     

Simulation modelling as a tool for evaluating surveillance programmes for detection of the Asian honeybee mite (Varroa destructor) in the South Island of New Zealand

AIM: To use a simulation model of the spread of the Asian honeybee mite (Varroa destructor) amongst apiaries, to evaluate a series of detection surveillance programmes for the South Island of New Zealand.

METHODS: Five potential incursion sites into the South Island were selected. A stochastic spatial simulation model, Varroa_sim, was adapted to simulate spread of the mite from these sites as a series of silent-phase propagating epidemics. The study population comprised all apiaries in the South Island registered in the Ministry of Agriculture and Forestry's (MAF's) apiary database in 2003. Six different surveillance programmes were simulated to try and detect the mite. Three of these were the actual multi-stage sampling plans conducted during the autumn (March–May) of 2001, 2002 and 2003, and the other three involved simple random sampling with sampling fractions equivalent to the actual numbers of apiaries tested in each of those years. The relative performances of the different surveillance plans were evaluated in terms of their ability to detect the mite early before it had spread too far and whilst there might still be a chance of eradication.

RESULTS: There were 13,798 registered apiaries in the South Island with valid map coordinates in the apiary database at the time of the study. The model generated 50 epidemics against which the various surveillance programmes were evaluated. The actual surveillance programmes conducted during the autumn of 2001 and 2002 generally performed fairly well in detecting the mite. The programme conducted in autumn 2003 detected the mite reasonably well in high-risk areas, but was very poor in low-risk areas. The simple random sampling strategies performed surprisingly well, and their relative rankings were proportional to the sampling fractions employed.

CONCLUSIONS: This study showed the value in using a spatial simulation model to generate plausible silent-phase epidemics, against which detection surveillance programmes could be evaluated, in ways that would otherwise not be possible.     

Hydrogen radicals, nitrogen radicals, and the production of O3 in the upper troposphere

The concentrations of the hydrogen radicals OH and HO2 in the middle and upper troposphere were measured simultaneously with those of NO, O3, CO, H2O, CH4, non-methane hydrocarbons, and with the ultraviolet and visible radiation field. The data allow a direct examination of the processes that produce O3 in this region of the atmosphere. Comparison of the measured concentrations of OH and HO2 with calculations based on their production from water vapor, ozone, and methane demonstrate that these sources are insufficient to explain the observed radical concentrations in the upper troposphere. The photolysis of carbonyl and peroxide compounds transported to this region from the lower troposphere may provide the source of HOx required to sustain the measured abundances of these radical species. The mechanism by which NO affects the production of O3 is also illustrated by the measurements. In the upper tropospheric air masses sampled, the production rate for ozone (determined from the measured concentrations of HO2 and NO) is calculated to be about 1 part per billion by volume each day. This production rate is faster than previously thought and implies that anthropogenic activities that add NO to the upper troposphere, such as biomass burning and aviation, will lead to production of more O3 than expected.     

Treatment of renal nephroblastoma in an adult dog

An 8-year-old Labrador retriever was diagnosed with a unilateral malignant nephroblastoma and hypertrophic osteopathy. The histopathologically malignant tumor was confined to the renal capsule, but the sarcomatous component was anaplastic, resulting in its classification as a Stage I tumor with unfavorable histopathology. The dog was treated with unilateral nephrectomy, vincristine, and doxorubicin. This dog has remained disease free for >25 months. Reported treatments of renal nephroblastoma in the dog have not described disease-free intervals of >8 months.     

Immunological response of male cockroaches to injection of Tetrahymena pyriformis

After injection of living tetrahymena into the hemocoels of male cockroaches, recovered hemolymph immobilizes washed ciliates. The immobilizing material is sensitive to heat and acid, and can be separated with ammonium sulfate. Hemolymph from immune animals confers protection in another animal into which it is injected. Immobilizing activity of the hemolymph from immune animals is associated with a nonreactive, normal protein component present in hemolymph from nonimmunized insects.     

Early central andean metalworking from mina perdida, peru

Copper and gold artifacts in contexts dated to approximately 3120 to 3020 carbon-14 years before the present ( approximately 1410 to 1090 calendar years B.C.) recovered in excavations at Mina Perdida, Lurin Valley, Peru, show that artisans hammered native metals into thin foils, in some cases with intermediate anneals. They gilded copper artifacts by attaching gold foil. The artifacts show that fundamental elements of the Andean metallurgical tradition were developed before the Chavin horizon, and that on the Peruvian coast the working of native copper preceded the production of smelted copper objects.     

Oestrous Synchronization,Ovarian Superovulation and Intraspecific Transfers From a Closed Breeding Colony of Inbred SLA Miniature Pigs

The inbred SLA miniature pig is a unique animal model developed for organ transplantation studies and pre‐clinical experimental purposes. Reported oestrous synchronization and superovulation treatments were examined in two SLA haplotypes (AA and DD) to allow collection of embryos for both practical embryo transfer and experimental technologies from a closed breeding colony. Pre‐puberal miniature pigs were poor responders to oestrous synchronization treatments, while post‐puberal sows were equivalent to commercial sows. Following superovulation, the ovulation number (corpora .hemorrhagica) was higher (p < 0.05) in the cycling sows when compared with non‐cycling sows. Ovulations were equivalent to commercial pre‐puberal gilts and non‐cycling sows (p > 0.05). No difference in ovulation number between haplotypes was observed, which differs from the previous report (DD>AA). Collection of zygotes for pronuclear injection was the highest in the non‐cycling post‐puberal miniature pig group (p < 0.05), although significantly lower when compared with the commercial pig treatment groups (p < 0.05). The incidence of cystic endometrial hyperplasia in our colony was equivalent to rates observed in commercial pigs. Pronuclear visualization following centrifugation was the highest in the non‐cycling miniature sow group and approximates to about 25% of ovulations and about half the rate observed in the commercial pigs (50%). Miniature pig embryos transferred between SLA haplotypes and transfer of DD embryos to commercial pigs resulted in live births at a higher efficiency than previously reported. This study demonstrates the feasibility of undertaking assisted reproductive technologies in a closed breeding colony of inbred SLA miniature pigs without compromise to the breeding programmes.