Adaptation and limitations of established hemagglutination inhibition assays for the detection of porcine anti-swine influenza virus H1N2 antibodies.

Hemagglutination inhibition (HI) has been a reliable method for determining porcine antibody levels to the well-characterized swine influenza virus (SIV) H1N1 and H3N2 subtypes. However, the recent emergence of the novel H1N2 serotype of SIV and the persistence of 2 other serotypes (H1N1 and H3N2) in the United States swine population represents a significant challenge to diagnostics. Both standardized and modified HI protocols were used in a blinded study to examine a collection of 50 control sera representing a total of 12 swine that were experimentally inoculated with one of the 3 SIV subtypes. Using these control sera data, a statistical basis for analysis was established in an attempt to classify 30 field sera with known case histories or seroprevalance into SIV serotype categories. By this approach 57% of the field sera could be classified into specific categories. The remaining samples that could not be classified reliably were most likely composed of heterogeneous anti-SIV antibody populations. These results indicate that although serological differentiation might be possible in a controlled environment, applications of these methods to field samples are currently problematic. Approaches other than HI will be required to fulfill the current need for SIV diagnostics and surveillance when specific serotype identification is required.     

Vaccination against the avian infectious bronchitis virus affects sperm concentration, sperm quality and blood testosterone concentrations in cockerels

1. It was previously found that cockerels vaccinated with live attenuated avian infectious bronchitis virus (AIBV) have decreased serum testosterone concentrations, epididymal stones and reduced fertility. The objectives of this study were twofold: to determine if reduced fertility following vaccination with live attenuated virus was the result of reduced sperm concentration or reduced sperm quality and to determine if vaccination with a killed strain of virus caused a similar reduction in sperm function in vivo. 2. Specific-pathogen-free Single Comb White Leghorn cockerels were divided into three treatment groups: no vaccination (NONVAC), vaccination with killed AIBV virus (KVAC) or vaccination with live attenuated AIBV virus (LVAC). Semen was collected daily from 17 to 27 weeks of age, and semen quality was assessed frequently by analysing sperm concentration, viability, motility, and ability to reach and interact with the ovum in vivo. Blood plasma was assayed for testosterone concentration. 3. Differences in sperm analysis among treatment groups were limited. Sperm viability was increased in NONVAC during week 20 which then decreased in week 22 when compared to vaccinated cockerels. Acrosome damage was increased in vaccinated cockerels in week 22, and decreased in weeks 25 and 27 when compared to controls, which correlate to the period of epididymal stone development. Plasma testosterone concentrations and sperm concentrations among treatment groups were different only at 16 and 19 weeks of age, respectively. There were no differences across treatment groups in sperm mobility through Accudenz or in numbers of sperm holes in perivitelline membranes of eggs following insemination with semen from 27-week-old cockerels. No differences were observed in viability or acrosome integrity between cockerels with and without epididymal stones within treatment groups. 4. In conclusion, pre-pubertal vaccination against AIBV and subsequent epididymal stone formation had a limited effect on sperm concentration, sperm quality and plasma testosterone concentrations. Vaccination with killed AIBV vaccine did not diminish effects on sperm function in vivo.     

Assessment of a point-of-care lactate monitor in emergency admissions of adult horses to a referral hospital

BACKGROUND: Blood lactate concentration [LAC] is considered a useful indicator of disease severity in horses. Agreement of point-of-care (POC) lactate monitors with laboratory standards has not been established for clinically abnormal horses. Hypothesis: It was hypothesized that results from a POC lactate monitor would be in agreement with a laboratory-based measurement of [LAC]. ANIMALS: The study included adult horses presented for emergency evaluation. METHODS: A prospective observational study was performed. [LAC] was measured with whole blood (AWB) and plasma (APL) by means of a POC monitor (Accutrend) and compared with results from whole blood measured by a laboratory blood gas analyzer (NOVA). RESULTS: Samples from 221 horses were used to compare the 2 lactate measurement techniques. Agreement (p +/- SE) was closest between APL and NOVA (0.97 +/- 0.01); an average observed difference of 0.15 +/- 0.89 (mean +/- SD) and 95% limits of agreement (LOA) -1.89, 1.59 also were found. Agreement was preserved and 95% LOA further decreased in horses with NOVA [LAC] of <5 mM and PCV <40%. Agreement was modest when testing whole blood samples on the POC monitor with increased 95% LOA. CONCLUSIONS AND CLINICAL IMPORTANCE: Results indicate close agreement between NOVA and the POC monitor when [LAC] was measured with plasma. Results were less consistent at higher [LAC] but sufficiently reliable to follow trends. Although whole blood may be used with the POC monitor to identify clinically important hyperlactatemia, results may be insufficiently reliable to monitor trends.     

Knock‐on effects of national risk assessments on the conservation of global biodiversity

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Application of a quantitative algorithm to restriction endonuclease analysis of Aujeszky's disease (pseudorabies) virus from a geographically localized outbreak.

A retrospective epidemiologic study was conducted to evaluate the application of an objective quantitative algorithm for estimating genetic similarity from restriction endonuclease analysis data. The analysis was performed to assist the determination of chronologic trends in an Aujeszky's disease viral epidemic in a geographic region. DNA from each viral isolate obtained during the epidemic was digested with 4 restriction endonucleases and molar ratio labeled to generate separate fragment patterns that were simultaneously compared using the algorithm. The resultant estimates of genetic similarity were then used in conjunction with time of virus isolation and specific geographic location of the outbreaks to identify the probable sources of infection and the patterns of spread among swine herds. This type of quantitative analysis enabled a more precise and objective approach than previously has been applied to the interpretation of restriction endonuclease data, thereby demonstrating the benefit of this methodology for the investigation of infectious disease outbreaks.     

Safety of long-term administration of a 0.01% fluocinolone shampoo in allergic dogs

Nine dogs with allergic dermatitis were bathed twice weekly with a 0.01% fluocinolone shampoo for 6 months to evaluate the shampoo's effects on the adrenal–pituitary axis, serum chemistries, complete blood counts and cutaneous histology. A group of 5 normal control dogs were bathed twice weekly for 6 months with the shampoo vehicle to determine whether or not the stress of bathing would have any effects on the monitored indices. Skin biopsies were evaluated at the beginning and end of the study, and serum chemistries and serum cortisols postadrenocorticotrophic hormone administration were evaluated every 8 weeks. There was no effect of the drug over time on serum chemistries or cortisol. Individual dogs in the treatment group had decreased epidermal and dermal thickness as well as decrease in size or number of sebaceous glands after treatment. None of the dogs exhibited the combination of morphologic changes characteristic of an atrophic dermatosis due to hyperadrenocorticism.     

Effects of agri-environment management for stone curlews on other biodiversity

Two-hectare unsown, tilled fallow plots put in place under agri-environment schemes for stone curlews Burhinus oedicnemus in England were surveyed for other bird species, brown hares Lepus europaeus, carabid beetles, vascular plants, butterflies and bumblebees. The results were compared with those from surveys within the crop in the same field and in neighbouring fields. This was done to test whether agri-environment management targeted at a single species also provided benefits to wider biodiversity. All groups except carabid beetles were more abundant, more likely to be recorded, or more species rich on plots than within the crop. Carabid beetle activity–density and species richness did not differ between the plot and the crop; activity–density of one functional group (predators) was lower on plots than in the crop. Six rare arable plant species were recorded, predominantly from plots, and the plots are considered to perform comparably to other agri-environment options available in England designed specifically for arable plants. One red-listed bird species of conservation concern (skylark Alauda arvensis) was more abundant on plots than in the crop, and three other red-listed species (linnet Carduelis cannabina, yellowhammer Emberiza citrinella, corn bunting E. calandra) were more likely to be recorded on plots than in the crop. A fifth (lapwing Vanellus vanellus) was almost exclusively recorded from plots, and was more likely to be recorded on plots categorised as in good condition for stone curlews. These results demonstrate that fallow plots that have been put in place for the recovery of stone curlews have considerable value for a range of other farmland biodiversity, although management for stone curlews may be detrimental to some taxa, such as carabid beetles, that are sensitive to the relatively frequent spring tillage that these plots receive.     

Interspecies comparison of morphology, ultrastructure, and proteome of mammalian keratin fibers of similar diameter

Sheep wool has traditionally been viewed as the representative mammalian keratin fiber for the purposes of describing morphology and protein composition. We have investigated narrow fibers from the under-hairs of a range of species both closely and distantly related to sheep, comparing structure and protein composition. Within this group, curvature was negatively correlated with diameter for all but mohair. The cortical cell types present in alpaca, rabbit, and mohair fibers differed structurally from wool, primarily in terms of their macrofibril architecture. Except for rabbit, each species' fibers contained three cell types, and except for mohair, cell types were distributed asymmetrically across the cortex. In mohair, the cell types were distributed annularly, and each cell type had regions in which intermediate filaments were packed into highly aligned hexagonal mosaics, much like the mesocortex in wool. Coupled with this, were differences in the protein profiles; the rabbit fiber contained extra keratins and keratin associated proteins, while only subtle differences were noted between mohair and Merino fibers. In both rabbit and mohair fibers, the relative abundance of keratin K85 was lower than that of Merino. These results suggest that there may be links between relative protein composition and fiber morphology, albeit complex ones.