Evaluation of intra-abdominal pressure in horses that crib

Objective: To measure intra-abdominal pressure (IAP) in horses that crib and compare it with IAP in horses that do not have this vice. Study Design: Cohort study. Animals: Healthy cribbing horses (cribbing cohort, n=8) and 8 healthy noncribbing horses (noncribbing cohort). Methods: A microsensor catheter was introduced into the peritoneal cavity through the right paralumbar fossa, using local anesthesia, for measurement of IAP. These pressures were recorded in 1-minute intervals for 2hours, while the horses were standing tied in a stall. IAPs of cribbing horses were compared to the noncribbing cohort. Results: Baseline IAPs were not significantly different between cribbing and noncribbing cohorts (P=.076); however, IAPs in the cribbing cohort were significantly increased when compared with the noncribbing cohort, during active cribbing behavior (P=.0016). Frequency of cribbing was not associated with increased IAP (P=.35). IAPs in the cribbing cohort remained significantly elevated compared with the noncribbing cohort, even after the behavior had ceased (P=.0002). Conclusion: Cribbing is associated with increased IAP in the horse, both during and after the behavior. © 2013 by The American College of Veterinary Surgeons

Direct Measurement of Intra-abdominal Pressures in a Horse by using a Solid Microsensor

Current techniques to measure intra-abdominal pressures in horses use metal cannulas. Concerns that the metal cannula could puncture abdominal viscera if left in place prevent continual pressure measurements. The aim of this study was to validate the use of a solid microsensor and digital monitoring system in the measurement of direct intra-abdominal pressure in horses by comparing its values with the ones simultaneously obtained by means of an intraperitoneal cannula. Ten healthy adult horses had intra-abdominal pressures measured simultaneously through an intraperitoneal cannula zeroed midway between the height of the tuber ishii and point of the shoulder and by the use of an intraperitoneal solid microsensor placed within the abdomen at the same level as the metal cannula. Three repeated intra-abdominal pressure measurements were obtained at rest, after placement of a nasogastric tube, and after placement of 5-L increments of water into the stomach, up to a total volume of 20 L of water. The difference between values obtained (after conversion) was 3.6 mm Hg. The correlation coefficient was 0.825. Direct intra-abdominal pressure monitoring with a solid microsensor allows continuous monitoring without concern for gastrointestinal perforation, is simple to use and to calibrate, and is minimally invasive. © 2013 Elsevier Inc

Surgical Technique and Short-Term Outcome for Experimental Laparoscopic Closure of the Epiploic Foramen in 6 Horses

Objective: To describe a laparoscopic technique for, and short-term outcome after, closure of the epiploic foramen (EF) in horses. Study Design: Descriptive, experimental study. Animals: Healthy, adult horses (n=6). Methods: Laparoscopic portals to approach the EF were identified in standing horses. Under laparoscopic observation, the gastropancreatic fold and right lobe of the pancreas were grasped with Babcock forceps and secured to the caudate hepatic lobe using helical titanium coils to obliterate the EF. Surgical procedure time and intra- and postoperative complications were recorded. Serial analysis of select serum enzymes was used as an indication of involvement of the pancreas and liver. Closure was reevaluated at 4 weeks using repeat laparoscopy, and necropsy was performed immediately after. Results: At initial surgery, EF closure was successful in all 6 horses; median surgical time was 40.5minutes (range, 22-110minutes). Serum gamma-glutamyl transferase (GGT) and sorbitol dehydrogenase (SDH) were not significantly altered by the surgical procedure; however, aspartate aminotransferase (AST) and amylase (AMY) were transiently increased. At repeat laparoscopic reevaluation, closure was complete in 5 horses, with partial closure of the EF observed in 1 horse. No complications related to the procedure were noted during or after surgery in any horse. Conclusions: EF closure in the standing horse can be accomplished without complications to the surrounding organs and vessels. © 2013 by The American College of Veterinary Surgeons

Ex-vivo evaluation of a modified Teno Fix® device repair pattern versus a 3-loop pulley for repair of equine flexor tendons

Objective: To compare the load to ultimate failure, load to a 2 mm gap, mode of failure, and gap at failure (mm) of the Teno Fix® (TF) to the 3‐loop pulley (3LP) for repair of equine tendon lacerations. The use of 4TF devices versus 5TF devices on load to ultimate failure and load to a 2 mm gap was also compared. Study Design: Ex vivo biomechanical study; unbalanced incomplete block (horse) design. Samples: Cadaveric equine forelimb superficial digital flexor tendon (n = 20 paired tendons). Methods: Ten tendon pairs were selected randomly and repaired with a 3LP and 4TF pattern, and 10 tendon pairs repaired with a 3LP and 5TF pattern. Load to ultimate failure, load to a 2 mm gap, mode of failure, and gap at failure were obtained using materials testing. Results: The 3LP had a significantly greater ultimate load to failure (P < .001, respectively) and a significantly higher load to a 2 mm gap than both TF repairs (P < .001, respectively). The most frequent mode of failure was suture pull‐out for the 3LP and anchor pull‐out for the TF. Gap at failure was significantly larger in the 3LP than both TF repairs (P < .001). The ultimate load to failure was significantly higher for the 5TF than the 4TF (P = .004) but there was no significant difference in load to a 2 mm gap, or gap at failure between both TF repairs (P = .11, P = .15, respectively). Conclusions: Neither TF repair was stronger than the 3LP in load to ultimate failure and load to a 2 mm gap. Addition of a fifth TF device significantly increased the load to ultimate failure but did effect the load to a 2 mm gap over the 4TF

Nitrogen pollution interacts with heat stress to increase coral bleaching across the seascape

Climate change is increasing the frequency and magnitude of temperature anomalies that cause coral bleaching, leading to widespread mortality of stony corals that can fundamentally alter reef structure and function. However, bleaching often is spatially variable for a given heat stress event, and drivers of this heterogeneity are not well resolved. While small-scale experiments have shown that excess nitrogen can increase the susceptibility of a coral colony to bleaching, we lack evidence that heterogeneity in nitrogen pollution can shape spatial patterns of coral bleaching across a seascape. Using island-wide surveys of coral bleaching and nitrogen availability within a Bayesian hierarchical modeling framework, we tested the hypothesis that excess nitrogen interacts with temperature anomalies to alter coral bleaching for the two dominant genera of branching corals in Moorea, French Polynesia. For both coral genera, Pocillopora and Acropora, heat stress primarily drove bleaching prevalence (i.e., the proportion of colonies on a reef that bleached). In contrast, the severity of bleaching (i.e., the proportion of an individual colony that bleached) was positively associated with both heat stress and nitrogen availability for both genera. Importantly, nitrogen interacted with heat stress to increase bleaching severity up to twofold when nitrogen was high and heat stress was relatively low. Our finding that excess nitrogen can trigger severe bleaching even under relatively low heat stress implies that mitigating nutrient pollution may enhance the resilience of coral communities in the face of mounting stresses from global climate change