Identification of a Mycoplasma ovis-like organism in a herd of farmed white-tailed deer (Odocoileus virginianus) in rural Indiana

Mycoplasma ovis is a hemoplasma parasite of sheep, goats, and reindeer; however, natural hemoplasma infection in white-tailed deer has not previously been reported. Subsequent to finding many coccoid, bacillary, and ring-shaped organisms, consistent with hemotropic mycoplasmas, on RBCs from a 72-day-old female white-tailed fawn, we sought to (1) identify the putative hemoplasma observed in blood from the fawn, (2) evaluate others in the herd for hemoplasma infection, and (3) identify clinicopathologic characteristics of hemoplasma-infected white-tailed deer. EDTA-anticoagulated whole blood was collected from the fawn and 8 apparently healthy does in the same herd. CBCs were performed on 7 nonclotted samples from the fawn and 6 does. DNA was extracted from all samples, followed by PCR amplification of bacterial (16S rDNA) and protozoal (18S rDNA) genes. The nearly complete 16S rDNA product from the fawn's sample was directly sequenced and compared with known sequences in the GenBank database. Samples from the fawn and 7 of 8 does were PCR-positive using hemoplasma-specific and M ovis-specific protocols. The fawn was PCR-negative for Anaplasma spp., Babesia spp., and Theileria spp. The 16S rDNA sequence from the fawn (GenBank accession number, FJ824847) was most closely related to M ovis (AF338268), having 98.5% sequence identity. The fawn had a mild nonregenerative anemia, a neutrophilic left-shift with toxic change, aspiration bronchopneumonia, and gastrointestinal disease. Hematologic values, including blood film evaluation, in infected does were unremarkable. The M ovis-like organism may have acted as either an opportunistic or primary pathogen in the fawn. The high occurrence of subclinical infections in the does suggests that white-tailed deer may act as wildlife reservoirs for M ovis.     

Monitoring the impacts of mountain pine beetle mitigation

Since 1999, the mountain pine beetle (Dendroctonus ponderosae Hopk. [Coleoptera: Scolytidae]) has impacted over 13 million hectares of pine forests in western Canada. Successful mitigation of the beetle depends on the accurate and timely identification of currently infested trees and on sustained control activities over several successive years. We monitored the success of mitigation activities in reducing damage caused by mountain pine beetle at two sites (A and B) on the leading edge of the current beetle epidemic in western Canada. Using three years of digital high spatial resolution aerial imagery (2006–2008) and one season of field measurements (2008), we estimated retrospective ratios of trees attacked by beetle in the current year (green attack) to trees attacked in the previous year (red attack), hereafter referred to as G:R. Our results indicate that mitigation activities slowed the rate of population growth, with G:R found to be decreasing or stable over sites A and B while mitigation was ongoing in 2005 and 2006 (site A 1.06:1; site B 0.32:1). When mitigation was discontinued over site A in 2007, the G:R increased markedly (1.94:1), while continued mitigation at site B in 2007 further reduced the G:R (0.22:1). Despite the cost associated with mitigation, its efficacy is rarely assessed and even more rarely documented. The approach presented herein enables a sample-based appraisal of mitigation efforts.     

Tensor Cubic Smoothing Splines in Designed Experiments Requiring Residual Modelling

Modelling response surfaces using tensor cubic smoothing splines is presented for three designed experiments. The aim is to show how the analyses can be carried out using the asreml software in the R environment, and details of the analyses including the code to do so are presented in a tutorial style. The experiments were all run over time and involve an explanatory quantitative treatment variable; one experiment is a field trial which has a spatial component and involves an additional treatment. Thus, in addition to the response surface for the time by explanatory variable, modelling of temporal and, for the third experiment, of temporal and spatial effects at the residual level is required. A linear mixed model is used for analysis, and a mixed model representation of the tensor cubic smoothing spline is described and seamlessly incorporated in the full linear mixed model. The analyses show the flexibility and capacity of asreml for complex modelling.Supplementary materials accompanying this paper appear online.     

Flight activity of <Emphasis Type="Italic">Cryptolestes ferrugineus</Emphasis> in southern New South Wales,Australia

Spatial and temporal aspects of flight activity of the rusty grain beetle, Cryptolestes ferrugineus (Stephens), were investigated in a grain-growing district in southern New South Wales, Australia. This species is now considered an important economic pest in Australia due to the development of a high level of resistance to phosphine. Flight activity was monitored at 4-weekly intervals near and away from grain silos. We present data for the first time from trapping with a commercial aggregation pheromone lure (active trapping phase), as well as data on C. ferrugineus by-catch from trapping using an aggregation pheromone lure for another species (passive trapping phase). There was a strong seasonal pattern to flight activity, with no flight detected during the winter months of June, July, or August. This appears to be primarily related to ambient temperature, with maximum temperatures above 20 °C initiating flight. Beetles were trapped both near and away from grain storages, demonstrating flight dispersal in the farm environment. The results of this study in southern New South Wales also show that C. ferrugineus beetles of both sexes are flying in the farm environment. During the passive trapping phase, the sex ratio of trapped beetles did not deviate from 1:1, but during active trapping, the sex ratio was biased to females (3:1). While more work is required, information garnered from this study provides a basis for management strategies for the control of C. ferrugineus in south-eastern Australia.     

Surveillance of equine respiratory viruses in Ontario

The objective of this project was to develop and implement an active surveillance program for the early and rapid detection of equine influenza viruses in Ontario. For this purpose, from October 2003 to October 2005, nasopharyngeal swabs and acute and convalescent serum samples were collected from 115 client-owned horses in 23 outbreaks of respiratory disease in Ontario. Sera were paired and tested for antibody to equine influenza 1 (AE1-H7N7), equine influenza 2 (AE2-H3N8), equine herpesvirus 1 and 4 (EHV1 and EHV4), and equine rhinitis A and B (ERAV and ERBV). Overall, the cause-specific morbidity rate of equine influenza virus in the respiratory outbreaks was 56.5% as determined by the single radial hemolysis (SRH) test. The AE2-H3N8 was isolated from 15 horses in 5 outbreaks. A 4-fold increase in antibody levels or the presence of a high titer against ERAV or ERBV was observed in 10 out of 13 outbreaks in which AE2-H3N8 was diagnosed as the primary cause of disease. In conclusion, AE2-H3N8 was found to be an important contributor to equine respiratory viral disease. Equine rhinitis A and B (ERAV and ERBV) represented an important component in the equine respiratory disease of performing horses.     

‘Friendly islands’ in an unfriendly system: Examining the process of Tonga's WTO accession

Tonga became the 151st member of the World Trade Organization (WTO) in July 2007. This article considers the issues that Tonga faced during its WTO accession process, and the potential impact of the reforms it has made in compliance with the terms of its accession. It notes that WTO membership may offer some benefits to Tonga, including improved market access for its exports and the provision of technical assistance. The taxation and regulatory reforms necessitated by accession might also have some positive development effects. However, this article argues that the costs of WTO accession outweigh these benefits. This is because Tonga faced numerous challenges during its accession process, which led it to agree to substantial trade concessions. In addition, the ‘special and differential’ (S&D) treatment provisions intended to assist developing countries like Tonga once they become WTO members are inadequate. While this article focuses on Tonga, the issues raised are relevant to other Pacific SIDS engaged in WTO accession negotiations, including Vanuatu and Samoa.