Abstract
BACKGROUND
Urinary acidification with ammonium chloride (AC) for urolith dissolution is a common treatment for goats with urolithiasis. Studies have reported increased fractional excretion of calcium (FECa) following AC administration, which could increase calcium-based urolithiasis. D,L methionine (MET) may result in similar acidification with less calcium excretion.
OBJECTIVE
To compare the effects of orally administered MET and AC on urine and blood pH, FECa, and blood HCO3 - concentrations in male goats.
METHODS
Prospective, randomized, crossover study. 12 healthy, 5-to-6-month-old Boer-cross wethers were administered 200 mg/kg of AC or MET orally for 14 days with a 7-day washout period between trials. Venous blood and urine samples were collected every 2 days. The effects of treatment and treatment day on urine and blood pH, HCO3 -, and FECa were assessed using linear mixed models.
RESULTS
Ammonium chloride and MET lowered least squares means (LSM) urine pH on day 6 (LSM, 7.49; 95% CI, 6.44 to 8.54), 8 (LSM, 7.78; 95% CI, 6.73 to 8.83), and 10 (LSM, 7.53; 95% CI, 6.49 to 8.58) when compared to day 0 (LSM, 8.23; 95% CI, 7.18 to 9.28). Some goats’ urine indicated acidification (pH < 7.0) in the first phase of the trial; however, for the entire trial, a significant treatment effect was not detected on urine pH, blood pH, blood HCO3 - or log10 FECa.
CLINICAL RELEVANCE
Ammonium chloride and MET acidified urine of some goats. Dietary cation-anion difference should be considered when treating healthy goats to acidify their urine.
Abstract
OBJECTIVE
To investigate whether a humeral intracondylar fissure (HIF) alters bone strain in the French Bulldog humerus, we developed a quantitative CT-based 3-D finite element (FE) model for virtual mechanical testing. We hypothesized that higher strains would be seen in the intracondylar region and lateral epicondylar crest if there was a HIF.
METHODS
Patient CT scans from 3 (n = 3) French Bulldogs were selected. Dog 1 had a closed distal physis and no HIF. Dog 2 had an open distal humeral physis but no HIF. Dog 3 had an open distal physis and a HIF. A 3-D FE model was built for FE analysis, and pressure was applied to the humerus over the region that contacts the radial head.
RESULTS
The maximum principal bone strain patterns differed in each of the models. A path of strain concentration mimicking the typical pattern of a lateral condylar fracture was only found in dog 3. Maximum principal strain exceeded 1% in parts of the lateral epicondylar crest in all 3 dogs.
CONCLUSIONS
We developed a patient-specific, quantitative CT-based 3-D FE model for virtual mechanical testing. We accepted our hypothesis. Strain concentration occurred in the intracondylar region and along the lateral epicondylar crest only when a HIF was present.
CLINICAL RELEVANCE
The presence of a HIF in French Bulldogs elevates maximum principal bone strain in this region and alters its path in an FE model, which suggests an increased risk of a lateral humeral condylar fracture.
Abstract
OBJECTIVE
Slow hoof growth poses a clinical challenge when hoof wear exceeds natural growth. Many treatment options have been reported without controlled prospective trials. The objective of this study was to evaluate the effect of transdermal CO2 on the rate of growth in treated hooves.
METHODS
A prospective, randomized, blinded, crossover study of 14 Warmblood mares. Horses were randomly assigned a number and allocated for treatment of the front feet with room air or CO2 for 30 minutes 3 times per week, and groups were switched after 5 weeks. Hoof growth was measured on the dorsal midline and the quarters of each front foot. The distance from coronary band to lines made on the hoof wall was measured at the beginning, middle, and end of the study. The percentage of change in length at each location relative to baseline was evaluated at 5 weeks and 10 weeks using nonparametric analyses.
RESULTS
All treatments were successfully administered. The left front medial (P = .028) and right front lateral (P = .03) sites of the CO2-treated hooves increased growth compared to the room air group at the 5-week point.
CONCLUSIONS
The results of this study suggest that repeated, noninvasive transdermal application of CO2 may accelerate hoof growth in normal horses over a 5-week treatment period.
CLINICAL RELEVANCE
This study suggests that transdermal CO2 may increase the rate of hoof growth in normal horses. The mechanism of action of this treatment is unclear, and further studies are required to fully elucidate the potential effects.
Abstract
OBJECTIVE
To assess the performance of transpulmonary thermodilution (TPTD) using room-temperature saline (CORT) and waveform-derived continuous CO (CCO) compared with TPTD using iced saline (COICED) as the indicator for measurements of CO in isoflurane-anesthetized dogs.
METHODS
8 Beagles aged 1 to 2 years (7.4 to 11.2 kg) were enrolled in this experimental study from March 21 to 31, 2023. Dogs were anesthetized with 0.01 mg/kg acepromazine, 5 to 6 mg/kg propofol, and isoflurane and were mechanically ventilated. Dogs were instrumented with a central venous catheter and a femoral arterial catheter equipped with a thermistor. The COICED, CORT, and pulse wave-derived CCO values were obtained at baseline, during infusions of phenylephrine and norepinephrine, and during blood withdrawal and replacement. Data were analyzed with a mixed effect model, Bland-Altman plots, and concordance. Percent error was calculated. P < .05 was used for significance.
RESULTS
Data were collected from 8 dogs. Significant effects of time and the interaction of time and method were found. Bland-Altman plots showed negligible bias with limits of agreement between −0.35 and 0.25 L/min for CORT versus COICED and −1.23 and 1.15 L/min for CCO versus COICED. Percent errors were 17.7% and 66.6%, respectively. In the 4-quadrant plots, the concordance rate was 95% and 68% for measurements obtained with CORT and for CCO, respectively.
CONCLUSIONS
Transpulmonary thermodilution using room temperature saline was accurate and able to track changes in CO. Continuous CO had a large percent error and low tracking ability.
CLINICAL RELEVANCE
Transpulmonary thermodilution using room temperature saline is reliable for monitoring CO and obviates the need for iced preparations in clinical scenarios.
Abstract
OBJECTIVE
To compare multiple noninvasive ECG methods in pond sliders based upon repeatability, ability to recognize standard waveforms, and measurability.
METHODS
The study was performed from November 2023 through January 2024. Ten healthy adult pond turtles were enrolled in the study. ECG tracings were obtained using 4 previously reported and 1 novel ECG methodology, using adhesive patches applied to the prehumeral fossae and abdominal scutes. The 50 ECG tracings were blinded by method and turtle, randomized for evaluation by 4 observers, and assessed for quality on a scale from 0 to 3.
RESULTS
Interobserver and intraobserver intraclass correlation coefficients for all tracings were 0.84 and 0.97, respectively, indicating an almost perfect agreement. The average score amongst the observers for each tracing was then averaged by method, ranging from 0.875 to 2.15. The novel method demonstrated a collective average of 2.15 and was the highest scoring method for 8 of 10 turtles.
CONCLUSIONS
Electrocardiogram utilizing methods that apply adhesive patches to the prehumeral fossae and either the abdominal scutes of the plastron or prefemoral fossae in pond turtles can be performed to produce recognizable waveforms.
CLINICAL RELEVANCE
Diagnostic tools, such as ECGs, are imperative to enhance veterinary care in nonconventional species, particularly with the rising trend of exotic pets worldwide.
Abstract
OBJECTIVE
To explain the relationship between cartilage erosion and medial patellar luxation (MPL) and to identify risk factors in dogs.
METHODS
A retrospective review was conducted on 90 dogs (103 stifles) surgically treated for MPL between January 2006 and March 2024. Data collected included signalment, side of operated stifle, patellar luxation grade, symptom duration, and lameness score. Cartilage erosion was evaluated for extent and location on the patella and femoral trochlea. Statistical analyses were conducted to identify risk factors.
RESULTS
The prevalence of cartilage erosion of the patella and femoral trochlea was 47.6% (49/103) and 54.4% (56/103), respectively, increasing with a higher grade of patellar luxation. Lesions were most prevalent in the distolateral patella and proximomedial trochlea, with generalized lesions more prevalent in grade IV. The extent of both lesions was significantly associated with age, patellar luxation grade, and symptom duration, while body weight significantly correlated only with the cartilage erosion of the patella. No significant correlation was observed with sex, side of operated stifle, or lameness score.
CONCLUSIONS
Many patients with MPL exhibited cartilage erosion in the patellofemoral joint, likely due to biomechanical mechanisms. Surgery can be indicated for patients with MPL, as it may prevent cartilage erosion while improving patellofemoral alignment and gait. When selecting surgical candidates, it is important to consider risk factors, such as patellar luxation grade, body weight, age, and symptom duration.
CLINICAL RELEVANCE
Early surgical treatment is recommended, especially for dogs with higher body weight and higher grade of MPL, to prevent cartilage erosion and secondary osteoarthritis.
Abstract
OBJECTIVE
Evaluate the incidence of Borrelia burgdorferi in cases of equine nuchal bursitis (NB) and investigate the relationship between elevated serum outer surface protein A (OspA) antibodies and the molecular identification of B burgdorferi in bursal tissue or synovial fluid. Additionally, describe clinical cases and compare the histologic changes in NB with and without detection of B burgdorferi.
METHODS
This was a retrospective multicenter cohort study (2013 to 2022). Medical records from horses with a diagnosis of NB and B burgdorferi PCR testing on NB tissue or synovial fluid were reviewed. The study population included 11 horses with a postmortem diagnosis of NB, 19 horses from the northeastern US with an antemortem diagnosis of B burgdorferi PCR–positive NB, and 15 healthy controls without evidence of NB and unvaccinated for B burgdorferi. Where serum was available, Lyme multiplex assay results were compared with controls and ELISAs targeting individual B burgdorferi antigens were performed. Histologic findings in nuchal bursa tissue were compared between NB cases with and without B burgdorferi PCR detection.
RESULTS
Serum OspA antibody values in B burgdorferi–positive NB cases (n = 13) were significantly elevated (P < .001) compared to controls (15), and OspA was the predominant antigen detected by ELISA (8). Histopathology did not vary between NB cases with (n = 9) and without (6) B burgdorferi PCR detection.
CONCLUSIONS
The presence of B burgdorferi in the nuchal bursa of horses is associated with increased serum OspA antibodies.
CLINICAL RELEVANCE
The role of B burgdorferi in equine NB may be underestimated, and targeted therapy requires investigation.
Abstract
OBJECTIVE
To evaluate sedation and IV xylazine requirements to achieve 45% of baseline head height above ground measurements following oral (PO) administration of 2 trazodone dosages.
METHODS
8 healthy, adult mares of various weights and breeds belonging to a university teaching herd were utilized in a blinded, crossover study design. Horses were randomly assigned to 1 of 3 PO treatments: control (no trazodone), trazodone at 3 mg/kg (low dose [LD]), or trazodone at 6 mg/kg (high dose [HD]). Before treatment, cardiac auscultation, EquiSed sedation score, and head height above ground (HHAG; cm) measurements were performed (baseline) followed by feeding of the treatment mixture. After 120 minutes, sedation score and HHAG were recorded. Xylazine was administered IV (0.25 mg/kg bolus followed by 0.1 mg/kg/min) until HHAG reached 45% of baseline or a total dose of 1 mg/kg was reached. Individual data for xylazine dosage, sedation scores, and HHAG were analyzed using mixed linear models with repeated measures.
RESULTS
Sedation scores were significantly improved (LD, P = .045; HD, P = .01) and HHAG was lowered (LD, P = .045; HD, P = .09) by trazodone administration. Xylazine dose requirements were increased by LD trazodone administration (increase of 0.26 ± 0.26 mg/kg; P = .03) and unchanged by HD (increase of 0.13 ± 0.25 mg/kg; P = .38).
CONCLUSIONS
Oral trazodone administration increases quantifiable sedation in horses. Xylazine requirements are significantly increased by LD trazodone administration.
CLINICAL RELEVANCE
Oral administration of LD trazodone may increase xylazine requirements. Further clinical studies are required to fully assess the clinical relevance of this finding on other parameters such as cardiovascular physiology.
Abstract
OBJECTIVE
To report local progression and survival in dogs following surgery and postoperative definitive radiotherapy (dRT) for management of soft tissue sarcoma (STS) and to evaluate risk factors for local progression and survival.
METHODS
Records were retrospectively reviewed at 9 referral hospitals for dogs managed with postoperative dRT between January 1, 2010, and January 1, 2020, following surgery for STS. Data related to presentation, surgery, dRT, systemic therapy, and outcome were abstracted. Selected variables were assessed for association with local progression and overall survival.
RESULTS
272 dogs were included. Histologic grade was reported in 249 dogs: 102 were grade 1 (40.9%), 120 were grade 2 (48.2%), and 27 were grade 3 (10.8%). Local progression was suspected or confirmed in 56 dogs. Local progression rates were similar for grade 1 (24 of 89 [26.7%]), grade 2 (23 of 111 [20.7%]), and grade 3 tumors (6 of 22 [27.3%]). Previous recurrence (P = .010) and subsequent distant metastasis (P = .014) were associated with more frequent local progression; intensity-modulated radiotherapy was associated with decreased local progression (P = .025) compared to other forms of delivery. Age (P = .049), grade (P = .009), previous recurrence (P = .009), and institution type for surgery (P = .043) were associated with overall survival.
CONCLUSIONS
Outcomes for most dogs were good; however, the frequency of local progression indicates an ongoing need to critically appraise local management strategies, particularly for low-grade STS. Intensity-modulated radiotherapy was associated with lower rates of local progression and may be preferred to less precise forms of delivery.
CLINICAL RELEVANCE
These data may guide clinicians when making decisions regarding dRT for management of STS.