Verification of skin-based markers for 3-dimensional kinematic analysis of the equine tarsal joint

REASONS FOR PERFORMING STUDY: Kinematic studies are usually based on tracking markers attached to the skin. However, complex joints, such as the tarsal joint, function in 3-dimensions (3D), and have therefore necessitated application of the invasive bone pin technique, limiting kinematic studies to the research laboratory. This study investigates the feasibility of using skin-based markers for 3D analysis of tarsal joint motion. HYPOTHESIS: Three-dimensional motions of the tarsal joint can be measured with an acceptable degree of accuracy using skin markers. METHODS: Retroreflective markers were attached over the tibial and metatarsal segments. Markers were tracked automatically at trot. Three-dimensional skin correction algorithms were used for correction of skin displacement, and 3D motions derived from the corrected (CSD) and uncorrected (USD) skin displacement were compared with data from a previous study in which those motions were described using bone-fixed markers (BFM) by correlation, root mean square errors (RMS) and shape agreement (SA) of the curves. RESULTS: The RMS of BFM and CSD were smaller than those of BFM and USD for all motions. The correlation coefficients of BFM and CSD were higher than those of BFM and USD. SA was good or fair for all motions except internal/external rotation and medial/lateral translation. CONCLUSIONS AND POTENTIAL RELEVANCE: With appropriate correction for skin movement relative to skeletal landmarks, skin markers can identify tarsal 3D motions for flexion/extension, abduction/adduction, cranial/caudal translation, and proximal/distal translation, allowing analysis and comparison of information between horses during swing and stance phases.     

Shedding consistency of strongyle-type eggs in Dutch boarding horses

Faeces of 484 horses were sampled twice with an interval of 6 weeks while anthelmintic therapy was halted. Faecal eggs counts revealed that 267 (55.2%) horses had consistently low numbers of eggs per gram faeces (EPG) (EPG < 100 or = 100), 155 (32.0%) horses had consistently high EPGs (EPG > 100). Horses with consistently high EPGs were more often mares with access to pasture, aged less than 6 or more than 23 years, that were dewormed at intervals longer than 6 months, and were treated for the last time more than 3 months before the start of the study. Horses with consistently low EPGs were more often male horses with no or limited access to pasture, that were dewormed at maximally 6-month intervals, and were aged between 6 and 23 years. The results are an indication that some horses have consistently low EPGs and perhaps could be used as non-treated animals in a selective anthelmintic treatment scheme aimed at the prevention of the development of anthelmintic resistance.     

Idiopathic gastric rupture in a Friesian foal

Acute idiopathic gastric rupture resulted in sudden death of a 4.5-months-old healthy Friesian foal. No morphological lesions were present which could explain the preceding gastric impaction. In this case hypodypsia may have been (partially) responsible for the impaction as only a mechanical drinking apparatus, unsuitably for horses, was available.     

Mycobacterium pinnipedii: transmission from South American sea lion (Otaria byronia) to Bactrian camel (Camelus bactrianus bactrianus) and Malayan tapirs (Tapirus indicus)

Tuberculosis infections caused by Mycobacterium (M.) pinnipedii in a South American sea lion, Bactrian camel, and Malayan tapirs kept in two zoological gardens spanning a time period of 5 years are reported. The zoos were linked by the transfer of one tapir. Conventional bacteriological and molecular methods were applied to detect the pathogen. Spoligotyping and MIRU/VNTR-typing performed to assess the genetic similarity revealed identical molecular characteristics of the isolates from all animals involved. Anti-tuberculosis antibodies were detected using ELISA and a recently developed serological rapid test. The study shows that: (i) using molecular methods, the assessment of the genetic relationship of infectious agents helps to confirm the routes of infection, and that (ii) immunological tests may help to detect tuberculosis infections ante mortem more reliably and early. This would prevent the transfer of tuberculosis by asymptomatic animals.     

Effects of hyperbaric oxygen on full-thickness meshed sheet skin grafts applied to fresh and granulating wounds in horses

OBJECTIVE: To determine the effects of hyperbaric oxygen therapy (HBOT) on full-thickness skin grafts applied to fresh and granulating wounds of horses. ANIMALS: 6 horses. PROCEDURES: On day 0, two 4-cm-diameter circular sections of full-thickness skin were removed from each of 2 randomly selected limbs of each horse, and two 4-cm-diameter circular skin grafts were harvested from the pectoral region. A skin graft was applied to 1 randomly selected wound on each limb, leaving the 2 nongrafted wounds to heal by second intention. On day 7, 2 grafts were harvested from the pectoral region and applied to the granulating wounds, and wounds grafted on day 0 were biopsied. On day 14, 1 wound was created on each of the 2 unwounded limbs, and the wounds that were grafted on day 7 were biopsied. All 4 ungrafted wounds (ie, 2 fresh wounds and 2 wounds with 1-week-old granulation beds) were grafted. The horses then received HBOT for 1 hour daily at 23 PSI for 7 days. On day 21, the grafts applied on day 14 were biopsied. RESULTS: Histologic examination of biopsy specimens revealed that grafts treated with HBOT developed less granulation tissue, edema, and neovascularization, but more inflammation. The superficial portion of the graft was also less viable than the superficial portion of those not treated with HBOT. CONCLUSIONS AND CLINICAL RELEVANCE: The use of HBOT after full-thickness skin grafting of uncompromised fresh and granulating wounds of horses is not indicated.     

A novel clinical scoring system for outcome prediction in dogs with acute kidney injury managed by hemodialysis

BACKGROUND: No reliable tool to predict outcome of acute kidney injury (AKI) exists. HYPOTHESIS: A statistically derived scoring system can accurately predict outcome in dogs with AKI managed with hemodialysis. ANIMALS: One hundred and eighty-two client-owned dogs with AKI. METHODS: Logistic regression analyses were performed initially on clinical variables available on the 1st day of hospitalization for relevance to outcome. Variables with P< or = .1 were considered for further analyses. Continuous variables outside the reference range were divided into quartiles to yield quartile-specific odds ratios (ORs) for survival. Models were developed by incorporating weighting factors assigned to each quartile based on the OR, using either the integer value of the OR (Model A) or the exact OR (Models B or C, when the etiology was known). A predictive score for each model was calculated for each dog by summing all weighting factors. In Model D, actual values for continuous variables were used in a logistic regression model. Receiver-operating curve analyses were performed to assess sensitivities, specificities, and optimal cutoff points for all models. RESULTS: Higher scores were associated with decreased probability of survival (P < .001). Models A, B, C, and D correctly classified outcomes in 81, 83, 87, and 76% of cases, respectively, and optimal sensitivities/specificities were 77/85, 81/85, 83/90 and 92/61%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: The models allowed outcome prediction that corresponded with actual outcome in our cohort. However, each model should be validated further in independent cohorts. The models may also be useful to assess AKI severity.     

Validation and standardization of virus neutralizing test using indirect immunoperoxidase technique for the quantification of antibodies to rabies virus

A virus neutralizing test using an indirect immunoperoxidase technique (VNT-IIP) for rabies has been developed for the titration of dog and cat serum samples in Japan. The VNT-IIP has the advantage that results obtained can be viewed by the naked eye. The purpose of this study was to validate the VNT-IIP and compare it with one of the international standard methods, the fluorescent antibody virus neutralization test (FAVNT). The VNT-IIP showed satisfactory repeatability, high analytical specificity and good accuracy. Regarding the comparison between the VNT-IIP and the FAVNT, the VNT-IIP showed good agreement (91.9%), high sensitivity (92.8%) as well as specificity (87.0%) and good correlation (r = 0.92). As described above, the validation of the VNT-IIP was satisfactory and the performances of the test proved to be equivalent to those of an international standard method.     

Selection on multiple QTL with control of gene diversity and inbreeding for long-term benefit

The purpose of this study was to develop and investigate selection strategies that aim at maximizing long-term genetic response while conserving gene diversity and controlling inbreeding in populations of limited effective size, assuming complete knowledge of all genes affecting a quantitative trait. Three selection strategies were proposed to select on 100 quantitative trait loci (QTL) and compared with truncation selection on breeding value. Alternative selection strategies aimed at maximizing the average breeding value of parents with a penalty on (1) the number of unfavourable QTL genotypes among parents (OS-I), (2) the negative of the logarithm of the frequency of the favourable allele at each QTL among parents (OS-II), and (3) the average pedigree relationship among parents (OS-III). When all QTL and their effects were known, the strategies examined were able to obtain extra long-term responses, conserve QTL diversity and reduce inbreeding, compared with truncation selection. Strategy OS-II was the most effective in conserving QTL diversity and OS-III in reducing inbreeding. By changing the magnitude of the penalties applied, the impact on long-term response, inbreeding and diversity can be controlled. Extra long-term responses over truncation selection of OS-I and OS-II were even greater when effects of QTL were estimated rather than assumed known, indicating the applicability of results to practical strategies for marker-assisted selection. Extra responses are expected to be reduced for larger population sizes.