Culicoides vectors of bluetongue virus in Chester Zoo

On four nights in June 2008, light traps were operated for Culicoides biting midges, the vector species for bluetongue virus (BTV), at five sites in Chester Zoo in north-west England. Over 35,000 Culicoides midges, of 25 species, were captured, including high densities inside animal enclosures. Over 94 per cent of all the Culicoides trapped were females of the Obsoletus group, which is implicated as the vector of BTV serotype 8 in northern Europe. The mean catch of this group per trap per night was over 1500, suggesting a potential risk of BTV transmission if the virus is introduced to Chester Zoo in the animals or midges in the summer.     

Factors that influence the decision to pursue an internship: the importance of mentoring

The purpose of the present study was (1) to determine if students from one veterinary school who participated in a mentoring/employment program with clinical faculty were more likely to pursue internship training than their peers and (2) to determine factors via survey that were influential to veterinary interns in making their decision to pursue post-graduate clinical training. Our hypothesis was that a mentoring relationship with clinical faculty was an important influence on the decision to participate in an internship. From 2006 to 2010, graduating students who participated in a mentoring/employment program with a clinical faculty member were 6.3 times more likely than non-participating students to pursue an internship. The majority of the participating students (90%) were initially hired/mentored as first- or second-year veterinary students. In the survey, interns ranked clinical faculty as having a greater influence than basic science faculty, private practice veterinarians, or house officers on their decision to pursue an internship; 82.8% reported that clinical faculty were most responsible for encouraging them to apply for an internship. Employment by their veterinary teaching hospital (41.5%) or directly by clinical faculty (26.2%) was commonly reported. Most interns (37%) decided to pursue an internship during their fourth year of veterinary school, 29.2% decided during their first year, and 15.3% decided in their second year. These results suggest that clinical faculty play a key role in a student's decision to pursue an internship and that it might be valuable to inform students about internships early in the veterinary curriculum.     

Fluid dynamics in suspension-feeding blackfish

Measurements of flow patterns and water velocities inside the oral cavity of blackfish (Orthodon microlepidotus), made with a fiberoptic endoscope and thermistor flow probe, revealed that gill-arch structures act in blackfish as barriers that direct particle-laden water to the mucus-covered roof of the oral cavity, where particles are retained. Gill-arch structures have previously been assumed to be the site of particle retention in suspension-feeding fishes. Water does not pass between these structures in blackfish, and they do not serve as filters that separate particles from the water. These results emphasize the importance of directly assessing flow velocity and direction inside the oral cavity of vertebrate suspension feeders, particularly at the level of the filtering elements.     

International conservation policy delivers benefits for birds in Europe

Conservation of the planet's biodiversity will depend on international policy intervention, yet evidence-based assessment of the success of such intervention is lacking. Poor understanding of the effectiveness of international policy instruments exposes them to criticism or abandonment and reduces opportunities to improve them. Comparative analyses of population trends provide strong evidence for a positive impact of one such instrument, the European Union's Birds Directive, and we identify positive associations between the rate of provision of certain conservation measures through the directive and the response of bird populations. The results suggest that supranational conservation policy can bring measurable conservation benefits, although future assessments will require the setting of quantitative objectives and an increase in the availability of data from monitoring schemes.     

Amber with Insect and Plant Inclusions from the Dominican Republic

An amber-bearing formation observed in the Dominican Republic in 1959 is described, and several insect orders, spiders, and plants found in amber are noted. An amber trace is recorded for Haiti, and the known fossil-bearing amber deposits or sites in the New World are summarized.     

Biosecurity for reproductive diseases.

Application of rational principles of risk management in designing an effective biosecurity plan for reproductive diseases can be an important part of a profitable operation. Knowledge of the disease status of the particular herd, the effective strategies for disease exclusion including test performance and reservoirs is necessary. Vaccination can be an effective part of a biosecurity program by increasing herd immunity and decreasing the impact of an outbreak, but by itself will not prevent infections and losses. A more comprehensive approach to disease control is needed. Development and implementation of a biosecurity program is an individualized effort undertaken for a particular operation. Knowledge of the disease status of the herd for each agent of concern and prioritization of the diseases most important in the herd is necessary. The biosecurity plan is then specific for the herd and the particular agent(s) of concern. Practitioners can apply knowledge of the epidemiology and ecology of disease agents to identify and implement logical control points for the individual herd. Many control strategies may be effective for more than one disease. A comprehensive look at the operation is necessary to make sure that the cost of the biosecurity plan does not exceed the return in prevented disease and increased production over the planning period.     

Effect of time of desiccation on seed potato yield and size distribution

Field studies in 1981 and 1982 determined the effect of time of top desiccation on yield and size distribution of seed potato (Solanum tuberosum L.) tubers. Kennebec, Sebago and Bintje were top desiccated with diquat at four times (7-day intervals) during the linear tuber bulking phase. The yields and size distributions of tubers harvested 2 wk after spraying were compared to the yield and size distribution in reference plots harvested at the time of spraying. Ease of top desiccation increased with later diquat applications. There was no interaction between the yield increase after spraying and time of spraying. Increases in total yield occurring after diquat application varied with year and among cultivars and averaged 2.3, 3.0, and 3.2 t/ha for Kennebec, Sebago, and Bintje, respectively. There were significant interactions between cultivars and time of desiccant application for yield of seed tubers (35–65 mm). Both time of harvest and desiccation resulted in a decrease in the percentage of total yield of small tubers and an increase in the percentage of large tubers.