Jorge A. Hernandez

Background No available literature supports the claim that the patellar and withdrawal (flexor) reflexes are the only reliable segmental reflexes in dogs. Objective Measure intra‐ and interobserver agreement of 8 segmental reflexes in dogs without clinical evidence of orthopedic or neurologic disease. Animals One‐hundred and one client‐ or staff‐owned dogs between 1 and 10 years of age with no clinical evidence of orthopedic disease, myelopathy, or neuromuscular disease. Methods Descriptive study. The intraobserver proportion of agreement (%) of responses to selected segmental reflexes in right versus left limbs by 3 observers was calculated and reported. The interobserver agreement of 2 observers of responses to selected reflexes was estimated by calculating proportions of agreement, kappa values, and 95% confidence intervals. A segmental reflex with an acceptable agreement was defined as that with a proportion of agreement ≥90% and a Kappa value ≥0.61 in both limbs. Results The intraobserver proportion of agreement for all 3 observers was high (≥95%) for the extensor carpi radialis, withdrawal, patellar, and cranial tibial reflexes. Between observers 1 and 3 and observers 2 and 3, the interobserver proportion of agreement was high (≥ 92%) for the extensor carpi radialis ( κ 0.66, not determined [ND]), withdrawal (both limbs, κ ND), patellar ( κ ND), and cranial tibial reflexes ( κ ND). Conclusions and Clinical Importance The extensor carpi radialis, withdrawal, patellar, and cranial tibial reflexes had a higher proportion of agreement and kappa values between 2 observers.

Background Estrogen modulates the renin‐angiotensin‐aldosterone system (RAAS) in women, but sex differences have not been fully explored in dogs. Objective We hypothesized that the RAAS profile of intact female (IF) Doberman Pinschers (DP) would differ from spayed female (SF) and intact male (IM) DP. Animals Eighteen healthy DP (6 IF, 6 SF, 6 IM). Methods Absolute and indexed RAAS metabolites, angiotensin‐converting enzyme (ACE) and ACE2 activities, and genotypes (pyruvate kinase dehydrogenase 4, titin, and ACE variants) were compared among sex groups using Kruskal‐Wallis or chi‐square tests, and linear regression controlling for age. Data are expressed as median (minimum, maximum) and P < .05 was considered significant. Results The ACE activity was higher in IF DP (656 pmol/L; 436, 784) compared to SF DP (411 pmol/L; 287, 451; P = .01) and IM DP (365 pmol/L; 276, 1200; P = .04) after controlling for age. Angiotensin II, angiotensin I, and plasma renin activity marker (PRA‐S) were higher in IF DP compared to SF DP, but not significantly ( P ≤ .25). After controlling for age, angiotensin 1‐7/angiotensin I was lower in IF DP compared to SF DP ( P = .01). Genotypes did not differ among groups. Most DP (94%) were ACE variant positive. Conclusions and Clinical Significance Sex and reproductive status influenced the RAAS of DP, with IF DP showing genotype‐independent higher ACE activity. These findings hold implications for sterilization practices in female dogs, and support sex and reproductive status as a source of variability in RAAS studies. Additionally, the frequency of the ACE gene variant was very high in this group of DP.

Background Atlantoaxial (AA) cerebrospinal fluid (CSF) collection in standing horses utilizes the controlled narcotic morphine, thereby limiting feasibility in field practice settings. Objectives To compare AA CSF collection time and reaction scores in horses sedated with morphine‐containing and opioid‐free sedation protocols: detomidine + morphine (DM), detomidine + xylazine (DX), detomidine + detomidine (DD), detomidine alone (D0); To develop a novel method for assessing sedation in standing horses using open‐source motion‐tracking software. Animals Six healthy adult horses. Methods Randomized crossover. Atlantoaxial CSF collections were performed weekly for 4 weeks. Horses received sedation protocols in random order. Procedure time and procedure reaction scores were compared between groups using Friedman test. Associations between procedure reaction scores and motion tracking variables (total distance and farthest excursion traveled by horse's head) were examined using scatter diagrams and linear regression. Results Procedure times were lower in horses sedated with DX (median: 36 seconds; range: 28 − 188), compared to D0 (121; 35 − 196; P = 0.04). Procedure reaction scores were lower in horses sedated with DX (median 1.0, range 1.0 to 2.0), or DM (1.8; 1.3 − 3.0) compared to DO (3.0; 2.3 − 3.0; P = .03). Reactions to dura mater puncture were recorded in 3 of 6 horses in D0 and DD groups, and 0 of 6 horses in DX and DM groups. Positive associations were observed between reaction score vs total distance or farthest excursion distance from baseline. Conclusions and Clinical Importance Both opioid‐free and morphine‐containing sedation protocols are acceptable for AA CSF collection. Motion‐tracking software represents a novel method for assessing sedation in standing horses.