The objectives of the current study were to quantify laying hen sternal carina (keel) and tibiotarsal bone and muscle quality using clinical CT, tissue level, and biomechanical measures; test associations among muscle transverse sectional area, bone mineral density, and biomechanical measures of bone quality; and determine whether CT measures of bone and muscle quality would be predictive of biomechanical measures of tibiotarsal bone quality.
60 40-week-old Hy-Line brown laying hens were used.
Associations among CT imaging, tissue level, and biomechanical measures of tibiotarsal and keel bone and muscle quality were tested using multivariate correlational analyses. Bivariate and generalized regressions were performed to determine whether CT measures were predictive of biomechanical measures of tibiotarsal bone quality.
Low positive correlations were identified between tibiotarsal muscle transverse-sectional area (cross-sectional area [CSA]) and bone mineral density (BMD) in the proximal location of the bone (r = −0.11 to 0.31). Tibiotarsal muscle CSA was also low to moderately correlated with biomechanical measures of bone quality (r = 0.20 to 0.41). Keel muscle CSA values were not correlated with keel BMD values, but they were correlated with biomechanical measures of tibiotarsal bone quality (r = 0.18 to 0.40). Keel CT measures of bone quality were not correlated with tibiotarsal CT measures of bone quality. At the proximal location, muscle CSA and tibiotarsal BMD were predictive of biomechanical failure load (F = 9.68, P = .0003muscle CSA; F = 9.13, P = .004tibiotarsal BMD).
Findings supported using noninvasive CT measures of muscle and bone quality in longitudinal research studies evaluating the effects of interventions on laying hen welfare.
To determine setting and temperature properties of diluted polymethyl methacrylate (PMMA) bone cement in vitro to assess utility for vocal fold augmentation in horses.
4 dilutions of PMMA equivalent to volumes of 15 mL, 20 mL, 25 mL, and 30 mL PMMA powder (PMMAp) in 10 mL solvent.
For each volume PMMAp, setting times (tset), peak temperatures (Tmax), and times to peak temperature (tmax) were determined using a temperature data logger in a 4-mL volume of PMMA. Injectability was assessed in vitro by documenting the force required to inject 0.2 mL PMMA through an 18-gauge 3.5-inch spinal needle attached to a 6-mL syringe at 1-minute intervals. Working time (twork) was calculated from a linear regression of injectability.
Peak temperatures increased with increasing volume of PMMAp: 56 °C, 86 °C, 99 °C, and 101 °C. Times for tset, twork, and tmax were inversely proportional to PMMA concentrations, resulting in tset of 23, 21, 17, and 14 minutes; twork of 22.75, 12.25, 7, and 4 minutes; and tmax of 28, 24, 19, and 16 minutes, respectively, for 15, 20, 25, and 30 mL PMMAp. Pairwise comparisons for all analyses were significant apart from Tmax for 25 and 30 mL PMMAp (P = .96) and twork for 20 and 25 mL PMMAp (P = .06).
Decreasing the concentration of PMMA bone cement resulted in longer working times and setting times; however, peak temperatures did not differ between the 2 strongest concentrations. Further research is warranted to quantify diluted PMMA properties for in vivo use for vocal fold augmentation in horses.
Treatment options for human dementia remain limited, and additional research is needed to develop and validate translational models. Canine cognitive decline (CCD) is common in older dogs and a major source of morbidity. The decline includes physiological and behavioral changes comparable to those in humans diagnosed with dementia. There are also corresponding changes in plasma neurodegenerative biomarkers and neuropathology. Biomarkers for both human and canine cognitive decline can be used to identify and quantify the onset of behavioral data suggestive of CCD. Successful correlations would provide reference values for the early identification of neurodegeneration in canine patients. This could allow for the subsequent testing of interventions directed at ameliorating CCD and offer translational value leading to safe and effective treatment of dementia in people. Research can help exploit, track, and provide benefits from the rapid progression of spontaneous naturally occurring CCD in a large heterogenous community of companion dogs. Research efforts should work to deliver information using blood biomarkers, comorbidities, and wearable technologies to track and evaluate biometric data associated with neurodegeneration and cognitive decline that can be used by both human and companion animal researchers. The synergistic approach between human and veterinary medicine epitomized in one health underscores the interconnectedness of the well-being of both species. Leveraging the insights gained from studying CCD can not only lead to innovative interventions for pets but will also shed light on the complex mechanisms of human dementia.
This retrospective clinical study was performed to determine the suitability and success rate of endodontic treatment of equine incisors presenting with apical and periapical disease.
All horses presented to a referral equine dental clinic between March 2013 and December 2019 specifically selected as candidates suitable for endodontic treatment were included in this study.
Initial clinical and radiographic presentation of incisor disorder cases suitable for endodontic treatment were recorded (88 incisors) and follow-up examination for long-term viability (8 months to 5 years) was performed in cases involving 32 incisors in total.
A total of 68 horses with 88 incisors were included in this study for endodontic restorative treatment. Different dental materials were used, with a temporary 3-layered technique using calcium hydroxide apically and temporary cement and resin composite occlusally most commonly used at the first treatment. Complete obturation with resin composite was performed in 48% of the cases requiring second treatments (50 incisors). Follow-up examination involving 32 incisors showed that successful endodontic treatment was achieved in 75% of the teeth treated.
Endodontic treatment of diseased incisors is a viable option in equid patients with a success rate comparable to humans in practice. The use of flowable resin composite as an obturation material has been shown to be successful at either the second treatment or in carefully selected patients at the first treatment.