Normal electrocardiographic QT interval in race-fit Standardbred horses at rest and its rate dependence during exercise

ObjectivesCardiac repolarization, measured as QT and T_peak to T_end (T_pT_e) intervals on the ECG, is important, as irregularities caused by diseases, ventricular hypertrophy, drugs and genetic defects can trigger arrhythmias which predispose human patients to syncope and sudden cardiac death. In horses, repolarization is not well described and therefore QT analysis cannot yet be used diagnostically. Therefore, we sought to describe reference values for the normal QT and T_pT_e intervals in Standardbreds and to determine the best method for heart rate (HR) correction.Animals30 Standardbreds.MethodsQT and T_pT_e intervals were measured during rest and exercise and plotted against HR converted to R_peak to R_peak interval (RR). Data were fitted with relevant regression models. Intra- and inter-observer agreement was assessed using Bland–Altman analyses.ResultsData were best described by a piecewise linear model (r² > 0.97). Average prediction error of this model was smaller than for both Bazett and Fridericia corrections. Coefficient of repeatability of intra- and inter-observer variability was 8.76 ms and 5.64 ms respectively and coefficient of variation was 1.77% and 2.76% respectively. T_pT_e increased with RR in stallions.ConclusionsThe QT interval in Standardbred horses shortens with decreasing RR interval (increasing HR) as in humans, but in a markedly different order as it clearly follows a piecewise linear model. The equine QT interval can be measured easily and there is small intra- and inter-observer variability. This model of the equine QT interval provides clinicians with a method that could support a diagnosis of repolarization disturbances in horses.     

Influence of pollen feeding on body weight and body size of the predatory mite Amblyseius swirskii (Acari,Phytoseiidae)

Journal of Plant Diseases and Protection - The nutritional quality of pollen was assessed measuring biomass and body size of freshly emerged, 1, 3, and 30 day old adult Amblyseius swirskii...     

Immunoglobulin concentrations in feline colostrum and milk, and the requirement of colostrum for passive transfer of immunity to neonatal kittens

The purpose of this study was to clarify whether cats have a colostral and milk phase of lactation differentiated by concentrations of immunoglobulins, and whether colostrum ingestion by newborn kittens is essential for optimal transfer of passive immunity. Milk from specific pathogen-free queens was analyzed for IgG and IgA concentrations from parturition through 6 weeks of lactation. Serum IgG and IgA concentrations from birth through 8 weeks of age were determined for colostrum-fed kittens, colostrum-deprived kittens that were fed a milk replacer, and colostrum-deprived kittens that were fostered onto queens in the milk phase of lactation. The total IgG and IgA concentrations in milk were significantly higher on the day of parturition than on day 7 of lactation, indicating cats do have a colostral phase of lactation. The predominant immunoglobulin in both colostrum and milk was IgG. The serum IgG concentrations in colostrum-deprived kittens fostered on queens in the milk phase of lactation were similar to colostrum-deprived kittens fed a milk replacer, and the concentrations were significantly lower than in colostrum-fed kittens for the first 4 weeks of life. The serum IgA concentrations in both colostrum-deprived groups were significantly lower than colostrum-fed kittens on day 2 after parturition, but were similar thereafter. Colostrum-deprived kittens fostered onto queens in the milk phase of lactation had failure of passive transfer of maternal antibodies. Protective concentrations of immunoglobulins can be restored in kittens with failure of passive transfer of immunity by parenteral administration of adult cat serum, but not by fostering on queens in mid-lactation.     

Correlation of antigen-specific IFN-γ responses of fresh blood samples from Mycobacterium avium subsp. paratuberculosis infected heifers with responses of day-old samples co-cultured with IL-12 or anti-IL-10 antibodies

Paratuberculosis is a chronic infection of the intestine of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). Early stage MAP infection can be detected by measuring cell-mediated immune responses using the interferon gamma (IFN-γ) assay. Whole blood samples are cultured overnight with specific MAP antigens followed by quantification of IFN-γ by ELISA. It is recommended that the time interval from sampling to culture does not exceed eight hours but addition of the co-stimulating cytokine interleukin 12 (IL-12) or anti-IL-10 antibodies to culture have been demonstrated to enhance IFN-γ responses of cultures stimulated with Johnin purified protein derivative (PPDj). Here we examined the correlation of IFN-γ production in response to PPDj and 15 recombinant antigens in day-old blood samples from heifers 10-21 months of age from a MAP infected herd with addition of either recombinant bovine IL-12 or anti-bovine IL-10 antibody with IFN-γ production in sample day samples. IFN-γ responses of sample day samples showed high correlation with responses to some antigens in day-old samples with addition of IL-12 or anti-IL-10 antibodies to cultures, indicating that day-old protocols can be applied as an alternative to the conventional IFN-γ protocol. Immunogenicity of the novel antigens was generally low for day-old samples. The most promising antigen using the day-old protocol with addition of IL-12 was latency protein LATP-2 as correlations, immunogenicity and diagnostic specificity collectively was high. The latency protein LATP-1 was the most promising antigen in the day-old protocol with addition of anti-IL-10 antibodies.     

Combining isotopic signatures of n(Sr)/n(Sr) and light stable elements (C,N, O,S) with multi-elemental profiling for the authentication of provenance of European cereal samples

The aim of this work (from the FP6 project TRACE) was to develop methods based on the use of geochemical markers for the authentication of the geographical origin of cereal samples in Europe (cf. EC regulations 2081/92 and 1898/06). For the first time, the potential usefulness of combining n(⁸⁷Sr)/n(⁸⁶Sr) and δ¹³C, δ¹⁵N, δ¹⁸O and δ³⁴S isotopic signatures, alone or with key element concentrations ([Na], [K], [Ca], [Cu] and [Rb], progressively identified out of 31 sets of results), was investigated through multiple step multivariate statistics for more than 500 cereal samples collected over 2 years from 17 sampling sites across Europe representing an extensive range of geographical and environmental characteristics.