Comparison of Short‐ and Long‐term Function and Radiographic Osteoarthrosis in Dogs After Postoperative Physical Rehabilitation and Tibial Plateau Leveling Osteotomy or Lateral Fabellar Suture Stabilization

Objectives— To compare short‐ and long‐term functional and radiographic outcome of cranial cruciate ligament (CrCL) injury in dogs treated with postoperative physical rehabilitation and either tibial plateau leveling osteotomy (TPLO) or lateral fabellar suture stabilization (LFS). Study Design— Prospective observational clinical study. Animals— Medium to large breed dogs with naturally occurring CrCL injury (n=65). Methods— Dogs with CrCL injury were treated with either TPLO or LFS and with identical physical rehabilitation regimes postoperatively. Limb peak vertical force (PVF) was measured preoperatively and at 3, 5, and 7 weeks, and 6 months and 24 months postoperatively. Stifles were radiographically assessed for osteoarthrosis (OA) preoperatively and 24 months postoperatively. Results— Thirty‐five dogs had LFS and 30 dogs had TPLO. Radiographic OA scores were significantly increased at 24 months compared with preoperative scores in all dogs. Radiographic OA scores preoperatively and at 24 months were not significantly different between treatment groups. PVF was significantly increased from preoperative to 24 months among both treatment groups but not significantly different between treatment groups preoperatively or at 3, 5, 7 weeks, 6, or 24 months. Conclusion— No significant difference in outcome as determined by ground reaction forces or radiographic OA scores were found between dogs with CrCL injury treated with LFS or TPLO. Clinical Relevance— LFS and TPLO remain good options for stabilizing stifles with CrCL injury with all dogs showing significant functional improvement. This study does not support the superiority of either surgical technique.     

Comparison of Multiplate,Platelet Function Analyzer‐200, and Plateletworks in Healthy Dogs Treated with Aspirin and Clopidogrel

Background

Platelet function testing may be warranted to assess response to aspirin and clopidogrel.

Hypothesis/Objectives

To evaluate the effects of aspirin, clopidogrel, or combination therapy using 3 platelet function tests: Multiplate Analyzer (MP), Platelet Function Analyzer‐200 (PFA), and Plateletworks (PW).

Animals

Six healthy laboratory Beagles.

Methods

Randomized double‐blind placebo‐controlled study (crossover design). Dogs were given aspirin 1 mg/kg, clopidogrel 2 mg/kg, or combination therapy for 1 week each, with a washout period of 2 weeks. Platelet function was assessed on days 0 and 7 of each phase using MP (adenosine diphosphate [ADP], arachidonic acid [AA], collagen [COL] agonists), PFA (P2Y, COL‐ADP [CADP], COL‐Epinephrine [CEPI] cartridges), and PW (ADP, AA, COL agonists). Platelet counts were obtained with impedance and optical counters.

Results

For MP, mean aggregation was decreased for COL and AA with combination therapy and for ADP with all treatments. For PFA, mean CT was increased for the CEPI cartridge with aspirin; and for the P2Y and CADP cartridges with clopidogrel or combination therapy. More dogs receiving clopidogrel showed an increase in PFA CT using the P2Y than the CADP cartridge. For PW, mean aggregation was decreased for AA with all treatments; for ADP with clopidogrel or combination therapy; and for COL with clopidogrel. The PW results with the 2 hematology counters showed almost perfect agreement.

Conclusion and Clinical Importance

All platelet function tests detected treatment effects in some dogs and may have utility for monitoring therapy.     

Comparison of milk and plasma pharmacokinetics of meloxicam in postpartum versus mid‐lactation Holstein cows

The objective of this study reported here was determine whether differences occurred in meloxicam pharmacokinetics between postpartum cows and mid‐lactation cows. Preliminary data from a separate study (P. J. Gorden, unpublished data) in postpartum cows demonstrated elevated plasma and milk concentration profiles compared to previously published data (Malreddy, Coetzee, KuKanich, & Gehring, 2013 ). Two different groups were enrolled, each with 10 cows. The treatment group (TRT) was postpartum cows treated with meloxicam, and the positive control (PC) group was cows in mid‐lactation treated with meloxicam. Plasma and milk meloxicam concentrations between the TRT and PC group were compared. Significant differences in meloxicam concentration in plasma were determined at all time points from 8 hr to 120 hr post‐treatment. In milk, there was a treatment (p = .003), time (p < .001), and treatment by time interaction (p < .001). Significant differences in milk meloxicam concentration were determined at all time points from 8 hr to 96 hr post‐treatment, except for the 16‐hr time point. The time needed for meloxicam to no longer be detected in milk of the TRT group was longer compared to the PC group, indicating that a longer milk withdrawal is needed. These data suggest higher bioavailability as the underlying mechanism. Further research is needed to determine the mechanisms underlying differences this outcome.     

Cardiac Troponin‐I Concentration,Myocardial Arteriosclerosis,and Fibrosis in Dogs with Congestive Heart Failure because of Myxomatous Mitral Valve Disease

Background

Few previous studies have investigated the association between biomarkers and cardiac disease findings in dogs with naturally occurring myxomatous mitral valve disease (MMVD).

Aim

To investigate if histopathological changes at necropsy could be reflected by in vivo circulating concentrations of cTnI and aldosterone, and renin activity, in dogs with naturally occurring congestive heart failure because of MMVD.

Animals

Fifty privately owned dogs with MMVD and heart failure.

Methods

Longitudinal Study. Dogs were prospectively recruited and examined by clinical and echocardiographical examination twice yearly until time of death. Blood was stored for batched analysis of concentrations of cTnI and aldosterone, and renin activity. All dogs underwent a standardized necropsy protocol.

Results

cTnI were associated with echocardiographic left ventricular end‐diastolic dimension (P < .0001) and proximal isovolumetric surface area radius (P < .004). Furthermore, in vivo cTnI concentrations reflected postmortem findings of global myocardial fibrosis (P < .001), fibrosis in the papillary muscles (P < .001), and degree of arterial luminal narrowing (P < .001) Aldosterone or renin activity did not reflect any of the cardiac disease variables investigated.

Conclusion and clinical importance

Cardiac fibrosis and arteriosclerosis in dogs with MMVD are reflected by circulating cTnI concentration, but not by aldosterone concentration or renin activity. Cardiac troponin I could be a valuable biomarker for myocardial fibrosis in dogs with chronic cardiac diseases.     

Isolation of Campylobacter spp. from Client‐Owned Dogs and Cats,and Retail Raw Meat Pet Food in the Manawatu,New Zealand

Campylobacter causes acute gastroenteritis in people worldwide and is frequently isolated from food, animals and the environment. The disease is predominately food‐borne but many routes of transmission and sources of infection have been described, including contact with pets. The prevalence of Campylobacter spp. in dogs and cats varies widely, and data on New Zealand pets are limited. This study aimed to investigate the prevalence of Campylobacter spp. in dogs, cats and retail raw meat pet food products in New Zealand and to characterize Campylobacter jejuni isolates using multilocus sequence typing (MLST). Ninety dogs and 110 cats examined at the Massey University Veterinary Teaching Hospital for elective procedures, and fifty locally purchased retail raw meat pet diets were sampled. Two culture protocols combining Bolton broth enrichment and mCCDA and CAT agars in a microaerobic atmosphere at 42°C and 37°C with species identification using PCR were performed. The prevalence of Campylobacter spp., C. jejuni, Campylobacter upsaliensis and Campylobacter helveticus was 36%, 13%, 23% and 1% in dogs and 16%, 5%, 5% and 7% in cats, respectively. One dog had Campylobacter lari confirmed, and three dogs and one cat had multiple Campylobacter spp. detected. Significantly more animals tested positive using CAT than mCCDA agar (P < 0.001). Being neutered, vaccinated for Bordetella bronchiseptica, fed dry diets and brought in for neutering were protective factors for dogs, whereas attendance for dental treatment was a risk factor for cats. Campylobacter spp. were isolated from 28%, C. jejuni 22%, C. lari 6% and Campylobacter coli 6% of food samples. Six isolates positive by Campylobacter genus PCR were identified as Arcobacter butzleri. Poultry meat was more likely to be positive than non‐poultry meat (P = 0.006). Of the 13 C. jejuni pet isolates with full MLST profiles, eight were of different sequence types (ST) and all nine food isolates were of different STs.     

Effects of 6% Tetrastarch and Lactated Ringer's Solution on Extravascular Lung Water and Markers of Acute Renal Injury in Hemorrhaged,Isoflurane‐Anesthetized Healthy Dogs

Background

Tetrastarch can cause acute kidney injury (AKI) in humans with sepsis, but less likely to result in tissue edema than lactated Ringer's solution (LRS).

Objectives

Compare effects of volume replacement (VR) with LRS and 6% tetrastarch solution (TS) on extravascular lung water (EVLW) and markers of AKI in hemorrhaged dogs.

Animals

Six healthy English Pointer dogs (19.7–35.3 kg).

Methods

Prospective crossover study. Animals underwent anesthesia without hemorrhage (Control). Two weeks later, dogs hemorrhaged under anesthesia on 2 occasions (8‐week washout intervals) and randomly received VR with LRS or TS at 3 : 1 or 1 : 1 of shed blood, respectively. Anesthesia was maintained until 4 hour after VR for EVLW measurements derived from transpulmonary thermodilution cardiac output. Neutrophil gelatinase‐associated lipocalin (NGAL) and creatinine concentrations in plasma and urine were measured until 72 hour after VR.

Results

The EVLW index (mL/kg) was lower at 1 hour after TS (10.0 ± 1.9) in comparison with controls (11.9 ± 3.4, P = 0.04), and at 4 hour after TS (9.7 ± 1.9) in comparison with LRS (11.8 ± 2.7, P = 0.03). Arterial oxygen partial pressure‐to‐inspired oxygen fraction ratio did not differ among treatments from 0.5 to 4 hour after VR. Urine NGAL/creatinine ratio did not differ among treatments and remained below threshold for AKI (120,000 pg/mg).

Conclusions and Clinical Importance

Although TS causes less EVLW accumulation than LRS, neither fluid produced evidence of lung edema (impaired oxygenation). Both fluids appear not to cause AKI when used for VR after hemorrhage in healthy nonseptic dogs.