Effect of Body Position on the 6-Lead ECG of Dogs

ECGs recorded from dogs show characteristic morphology and changes in morphology with various disease states. These changes are determined by comparing individual recordings to reference ranges established from recordings obtained from normal dogs in right lateral (RL) recumbency. Using these reference ranges for ECGs recorded from dogs in other positions may not be valid. We compared ECG complexes from 39 normal dogs obtained in RL, left lateral (LL), and standing (ST) body positions. ECGs from dogs in ST position showed increased Q-wave and R-wave amplitudes in leads I and II, increased R-wave and S-wave amplitudes in leads aVR and aVL, and decreased R-wave and S-wave amplitudes in lead III when compared with recordings obtained in RL position. ECGs from dogs in LL position showed increased R-wave amplitude in leads II, III, and aVF and S-wave amplitude in lead aVL but decreased R-wave amplitude in lead aVR when compared with recordings obtained in RL position. The mean electrical axis (MEA) shifted to the left in ST position but remained within the normal range in LL position. We determined that both a change in the relative position of the recording electrodes with respect to the heart as well as a change in intrathoracic cardiac position contributed to these changes. P-wave amplitude, P-R and S-T intervals, and QRS complex durations remained unaltered by changes in body position. Our findings indicate that ECGs of dogs recorded in RL, LL, and ST positions yield dramatically different results, and investigators should use position-specific reference ranges to minimize potential misinterpretation of ECG results

Variation in blood selenium and serum vitamin E in reindeer (Rangifer tarandus tarandus) described by location, husbandry, and season

Reindeer (Rangifer tarandus tarandus) are important livestock for arctic and subarctic herders, including those in North America, but as climate change affects traditional herding practices, alternative methods of rearing (such as captive rearing) will likely become common. Proper nutrition is critical in livestock production, but there is minimal information available on circulating nutrient concentrations in reindeer, who are adapted to a unique climate. This study looks at 2 important antioxidants. Blood and serum were taken from female reindeer from three herds:  a free-ranging herd from the Seward Peninsula, Alaska (AK), during the summer, and two captive herds (one in Fairbanks, AK and one in Upstate New York (NY) during the summer and winter. Selenium (Se) and vitamin E concentrations were described stratified on season (when possible), location, and management practices (captive or free range). Herd mean values across seasons for Se ranged from 2.42 to 4.88 µmol/L. Herd mean values across seasons for vitamin E ranged from 5.27 to 6.89 µmol/L.

Povijesno kohortno istraživanje prevalencije paratuberkuloze u stadu mliječnih krava

The objective of this retrospective cohort study was to evaluate the efficacy of selected Johne’s-disease control measures on a dairy farm. The Dairy Comp 305 archive files for 455 Holstein dairy cows born in 1996, 1997 and 1998 were used. The tested heifers were grouped into annual birth cohorts. Kinetic ELISA (KELA) results and fecal-culture results for solid- (HEYM) and liquid-media systems (ESP Culture System II) were described and compared between birth cohorts. Only one animal had a high KELA score. Nevertheless, the fecal-culture results showed that there were animals shedding in the highest category even in test year 2001 in all birth cohorts. The 1997 birth cohort showed a lower rate of fecal positive culture results compared to the 1996 and 1998 cohorts. Out of 455 cows in the study, 43 were culled because of Johne’s disease clinical signs or high fecal-culture results. This cause-specific cull risk was 20% (21/105 animals) in 1996, 12% (12/100 animals) in 1997 and 10% (10/100 animals) in 1998. Survival analysis, where animals were classified according to the KELA and fecal-culture results for all animals tested as heifers, showed that heifers with the highest KELA value and/or the highest fecal-culture results had the shortest survival time in the herd. Analysis of birth cohorts led to an enhanced understanding of the response to the Johne’s-control procedures. In this herd, early shedding led to short herd-survival.Svrha ovoga povijesnoga kohortnoga istraživanja bila je procijeniti djelotvornost predloženih kontrolnih mjera za paratuberkulozu (Johneovu bolest) na farmi mliječnih krava. Rabljene su arhivske datoteke iz računalnog programa Dairy Comp 305® za 455 krava holštajnsko-frizijske pasmine, oteljenih 1996., 1997. i 1998. godine. Pretražene junice bile su svrstane u skupine prema godini kada su bile oteljene. Opisani su rezultati kinetičkoga imunoenzimnoga testa (KELA) i rezultati izdvajanja uzročnika iz izmeta na čvrstoj (HEYM) i tekućoj hranjivoj podlozi (ESP Culture System II) te uspoređeni između promatranih skupina. Samo jedna životinja bila je pozitivna KELA testom. Usprkos tome rezultati izdvajanja uzročnika pokazali su da su postojale životinje s pozitivnim nalazom u promatranoj 2001. godini u svim istraživanim skupinama. Skupina životinja oteljenih 1997. godine pokazala je manju stopu bakteriološki pozitivnih uzoraka fecesa u usporedbi sa skupinama iz 1996. i 1998. godine. Od 455 krava promatranih u istraživanju, 43 su bile izlučene zbog kliničkih znakova paratuberkuloze ili zbog pozitivnih rezultata pretrage fecesa. Uzročno specifični rizik za izlučivanje bio je 20% za životinje oteljene 1996. godine. Za životinje oteljene 1997. godine uzročno specifični rizik za izlučivanje bio je 12%, a 1998. godine spustio se na 10%. Analiza preživljavanja u kojoj smo životinje svrstali prema rezultatima KELA i izdvajanja bakterije iz svih životinja koje su bile pretražene kao junice, pokazala je da junice s najvišim pozitivnim nalazom KELA i bakterija imaju najkraću stopu preživljavanja u stadu. Analiza skupina prema godini teljenja omogućila je bolje razumijevanje učinkovitosti programa mjera za kontrolu paratuberkuloze u stadu. Rana pojava i pravovremena dijagnostika paratuberkuloze dovodi do skraćenja životnoga vijeka životinja u stadu

The Sleep of Shelter Dogs Was Not Disrupted by Overnight Light Rather than Darkness in a Crossover Trial

Dogs in shelters may be unattended at night. The purpose of this study is to describe the night-time behavior of dogs in a shelter and to determine if artificial light affected their sleeping patterns. Ten dogs were video-recorded under both light and dark conditions and their behavior recorded using focal animal sampling. The dogs were lying down 649 ± 40 min (mean ± SD) in the light condition and 629 ± 58 min in the dark condition each night. They awoke, stood up, turned around and then lay down again every 48 to 50 min. There was no significant difference in time spent lying between the two conditions (p > 0.05). Light did not seem to affect their behavior. The conclusion is that dogs in shelters may sleep in the absence of people and that light does not disrupt their sleep patterns

Evaluation of metaphylactic RNA interference to prevent equine herpesvirus type 1 infection in experimental herpesvirus myeloencephalopathy in horses

Objective-To evaluate metaphylactic RNA interference to prevent equine herpesvirus type 1 (EHV-1) infection in experimental herpesvirus myeloencephalopathy in horses and to determine whether horses infected with a neuropathogenic strain of the virus that develop equine herpesvirus myeloencephalopathy (EHM) have differences in viremia. Animals-13 seronegative horses. Procedures-EHV-1 strain Ab4 was administered intranasally on day 0, and small interfering RNAs (siRNAs [EHV-1 specific siRNAs {n = 7} or an irrelevant siRNA {6}]) were administered intranasally 24 hours before and 12, 24, 36, and 48 hours after infection. Physical and neurologic examinations, nasal swab specimens, and blood samples were collected for virus isolation and quantitative PCR assay. Data from the study were combined with data from a previous study of 14 horses. Results-No significant difference was detected in clinical variables, viremia, or detection of EHV-1 in nasal swab specimens of horses treated with the EHV-1 targeted siRNAs (sigB(3)-siOri(2)) versus controls. No significant differences in viremia were detected between horses that developed EHM and those that did not. Conclusions and Clinical Relevance-Administration of siRNAs targeted against EHV-1 around the time of EHV-1 infection was not protective with this experimental design. Horses infected with the neuropathogenic EHV-1 strain Ab4 that developed EHM did not have a more pronounced viremia