Disturbances that alter cross-habitat food web linkages can lead to whole-scale changes to aquatic systems. In coastal rivers of the Everglades (Florida, U.S.A.), increases in rainfall inundate adjacent floodplains, providing habitat for floodplain fish and macroinvertebrate species. In the dry season, rainfall decreases and floodplains dry, forcing floodplain prey into these river systems. These prey provide a prey subsidy for an estuarine predator, the common snook (Centropomus undecimalis). In 2011, severe drought impacted the region, likely affecting this prey subsidy. In this study, we ask (i) did the 2011 drought affect the magnitude and composition of floodplain prey subsidies to the common snook? and (ii) if species composition changed, were there energetic differences between the pre- and post-disturbance prey species? Results showed that 1 year after the drought, subsidies to the common snook decreased by 75%. On top of that decrease in overall flux, diet composition of the common snook switched from floodplain fishes to drought-tolerant floodplain macroinvertebrates. Lastly, energetic analyses showed that these postdrought macroinvertebrate prey subsidies had 43% less calories than floodplain fishes. Our findings illustrate the importance of considering not only the biomass that transfers from one food web to the next, but also how the species composition of the subsidy may affect incorporation into recipient food webs.

OBJECTIVE To compare use of a 3-level self-locking suture (3LSLS) technique with use of a previously described modified 3-loop pulley (M3LP) technique to repair rupture of the proximal aspect of patellar tendons in limbs from canine cadavers. SAMPLE Paired hind limbs of 6 adult mixed-breed dogs. PROCEDURES A limb from each pair was randomly assigned to be repaired by the 3LSLS technique or M3LP technique with size-2 ultrahigh-molecular-weight polyethylene and size-0 monofilament polypropylene suture, respectively. Limbs were prepared, and each patellar tendon was transected at a site chosen to simulate rupture at the proximal aspect. Tendons were repaired with the assigned techniques and mechanically tested with a biaxial servohydraulic test system; the clamp was distracted until the repair failed. Force at 1 -mm gap formation, 3-mm gap formation, and repair failure and gap size at failure were measured and compared between methods. Mode of failure was recorded. RESULTS There was no significant difference between methods for the force required to produce a 1 - or 3-mm gap in the repair. The 3LSLS technique required a significantly higher load for complete failure; gap formation immediately before failure was significantly greater for this method than for the M3LP technique. Four of 6 repairs with the M3LP technique and 0 of 6 repairs with the 3LSLS technique failed by suture breakage. CONCLUSIONS AND CLINICAL RELEVANCE The 3LSLS technique with size-2 ultrahigh-molecular-weight polyethylene suture was as effective at resistance to 1 - and 3-mm gap formation as the M3LP with size-0 monofilament polypropylene suture.

Although the goat is an established animal model in anterior cruciate ligament (ACL) research, in vivo kinematics associated with ACL deficiency have not been previously described in this species. Three-dimensional knee kinematics were determined before and after unilateral ACL transection in eight goats. Fluoroscopic imaging of the knees during treadmill walking and force-platform gait analysis during over-ground walking were performed prior to ACL transection, and 2 weeks, 3 months, and 6 months after ACL transection. Transient lameness of the ACL-transected limb was noted in all goats but resolved by 3 months post-ACL transection. Increased extension of 8.7°to 17.0°was noted throughout the gait cycle in both the ACL-transected and the contralateral unaffected knees by 3 months post-ACL transection, in a bilaterally symmetric pattern. Peak anterior tibial translation increased by 3 to 6 mm after ACL transection and persisted over the 6-month study period. No changes in axial rotation or abduction angle were observed after ACL transection. Unilateral ACL deficiency in goats resulted in persistent kinematic alterations, despite the resolution of lameness by 3 months post-ACL transection.