Comparison of sedation with dexmedetomidine administered subcutaneously at 2 different locations on the head in dogs.

Objective: This study aimed to compare the sedative effects of dexmedetomidine administered to dogs subcutaneously (SC) at the Governing Vessel 20 (GV20) acupuncture point and at another point on the head. Animals and procedure: Ten client-owned dogs were included. Dogs were sedated 2 times, 14 d apart, with 200 µg/m2 of dexmedetomidine, SC, at GV20 and at a point at the base of the ear (SC-head). The sedation was assessed with a sedation scale and a Dynamic and Interactive Visual Analogue Scale (DIVAS). The ease of performing radiographic studies, physiological parameters, and adverse events were recorded. Statistical linear mixed-effect models (ANOVA) were applied. Statistical significance was set at P < 0.05. Results: The time to sedation and sedation scores were similar for both groups. The level of sedation achieved was adequate to perform orthopedic radiographs for 9/10 (90%) cases in the GV20 group and 8/10 (80%) cases in the SC-head group. Heart and respiratory rates decreased significantly over time in both groups (P < 0.001). Adverse events were infrequent and self-limiting. Conclusion: Our study provides evidence that SC administration of dexmedetomidine on the head, at the GV20 point or at the base of the ear, is easy and provides a sufficient level of sedation to obtain orthopedic radiographs in dogs.

Comparaison de la sédation avec de la dexmédétomidine administrée par voie sous-cutanée à deux sites différents sur la tête de chiens. Objectif: Cette étude a pour but de comparer les effets sédatifs de la dexmédétomidine administrée par voie sous-cutanée (SC) au point d'acupuncture VG20 et à un autre point sur la tête, non lié à la relaxation/sédation, chez le chien. Animaux et procédure: Dix chiens de clients ont été inclus dans cette étude clinique, prospective, croisée, randomisée et à l'aveugle. Les chiens ont été sédatés deux fois, à 14 jours d'intervalle, avec une injection de 200 µg/m2 de dexmédétomidine sous-cutanée au point d'acupuncture VG20 et à un autre point sur la tête, à la base de l'oreille (SC-tête). La durée et la qualité de la sédation ont été évaluées avec une échelle de sédation et une échelle analogue visuelle dynamique et interactive (DIVAS). La facilité de réaliser des études radiographiques, les paramètres physiologiques et les effets secondaires ont été enregistrés. Des modèles statistiques linéaires à effet mixte (ANOVA) ont été réalisés. Les résultats étaient considérés comme significatifs quand P < 0,05. Résultats: Le temps nécessaire pour atteindre un niveau de sédation adéquat et les scores de sédation étaient comparables entre les deux groupes. Le niveau de sédation était adéquat pour réaliser des radiographies orthopédiques chez 9/10 (90 %) des cas dans le groupe VG20 et 8/10 (80 %) des cas dans le groupe SC-tête. Les fréquences cardiaque et respiratoire diminuaient significativement dans le temps pour les 2 groupes (P < 0,001). Les effets indésirables étaient peu fréquents et auto-limitants. Conclusion: Notre étude suggère que l'administration sous-cutanée de dexmédétomidine sur la tête, que ce soit au point VG20 ou à la base de l'oreille, est facile et permet d'obtenir un niveau de sédation suffisant pour réaliser des radiographies orthopédiques chez des chiens sains.(Traduit par les auteurs).

Residual volume of extruded disc material and residual spinal cord compression measured on postoperative MRI do not predict neurological outcomes in dogs following decompressive surgery for thoracolumbar intervertebral disc extrusion.

Published studies on the validity of using quantitative MRI measures of pre- and postoperative spinal cord (SC) compression as prognostic indicators for dogs undergoing surgery for intervertebral disc extrusion (IVDE) are currently limited. The aim of this retrospective analytical study was to describe the volume of postoperative residual extradural material (VREM) and the ratio of the cross-sectional area (CSA) of maximum SC compression to the CSA of SC in a compression-free intervertebral space as MRI measures of preoperative and postoperative compression (residual spinal cord compression, RSCC), and to compare these measures between the neurological outcome in a group of dogs. Inclusion criteria were dogs that underwent surgery for thoracolumbar IVDE, were imaged pre- and immediately postoperatively by MRI, and had a neurological follow-up examination 2 to 5 weeks postoperatively. Two blinded observers independently performed measurements in pre- and postoperative MRI studies. Dogs were classified into positive outcome (PO) and negative outcome (NO) groups based on follow-up neurologic examination scores. Seventeen dogs were included (12 PO, 5 NO). Interobserver agreement for MRI measurements was good to excellent (ICCs: 0.76-0.97). The prevalence of residual extradural material in postoperative MRI studies was 100%. No significant differences in mean preoperative SC compression, mean RSCC, mean SC decompression, or VREM were found between outcome groups (P = .25; P = .28; P = .91, P = .98). In conclusion, neither postoperative VREM nor RSCC could predict successful neurological outcomes.

Evaluation of the Immunoprotective Capacity of Five Vaccine Candidate Proteins against Avian Necrotic Enteritis and Impact on the Caecal Microbiota of Vaccinated Birds.

Avian necrotic enteritis is an enteric disease of broiler chickens caused by certain pathogenic strains of Clostridium perfringens in combination with predisposing factors. A vaccine offering complete protection against the disease has not yet been commercialized. In a previous study, we produced five recombinant proteins predicted to be surface-exposed and unique to necrotic enteritis-causing C. perfringens and the immunogenicity of these potential vaccine candidates was assessed in broiler chickens. In the current work, the relative contribution of the antibodies raised by these putative antigens to protect broiler chickens was evaluated using an experimental necrotic enteritis induction model. Additionally, the link between the immune response elicited and the gut microbiota profiles in immunized birds subjected to infection with virulent C. perfringens was studied. The ELISA results showed that the IgY antibody titers in vaccinated birds on days 21 and 33 were significantly higher than those on days 7 and 14 and those in birds receiving the adjuvant alone, while the relative contribution of the specific immunity attributed to these antibodies could not be precisely determined using this experimental necrotic enteritis induction model. In addition, 16S rRNA gene amplicon sequencing showed that immunization of birds with recombinant proteins had a low impact on the chicken caecal microbiota.

Morphological Evaluation of Transscleral Laser Retinopexy in Rabbits: Comparison of Optical Coherence Tomography and Histologic Examinations.

Transscleral retinopexy is a preventive technique used against retinal detachment. Fundus examination can allow the monitoring of morphological retinal changes in the progression of photocoagulation lesions, without offering details on the morphological changes by the retinal lesion. The aim of the study was to assess the progression of photocoagulation lesions induced by transscleral retinopexy (840 nm diode laser), by comparing the optical coherence tomography (OCT) and histological images over a period of six weeks on eight pigmented New Zealand healthy rabbits (four males and four females; n = 16 eyes). All rabbits underwent transscleral retinopexy on their left eye on day 0 (D0). Measurements of the photocoagulation lesions were obtained in vivo on D0, D7, D15, D21, and D42 by acquiring OCT images of both eyes from all rabbits. On D1, D7, D21, and D42, two rabbits were euthanized, and their eyes were enucleated. A significant effect by time on the decrease in the central retinal thickness of the photocoagulation lesion was observed from D1 to D7 (p = 0.001); however, no such effect was observed on the horizontal length ((HL) p = 0.584) of the lesion surface. The reliability between the OCT and histological measurements, which were evaluated using intraclass correlation coefficients, was excellent for measuring the retinal thickness at the center (ICC = 0.91, p < 0.001), moderate for the right side of the retinal lesions (ICC = 0.72, p = 0.006), and not significant for the left side and HL (p = 0.055 and 0.500, respectively). The morphological changes observed in the OCT and histopathological images of the photocoagulation lesions were qualitatively described over time. OCT is an effective tool for monitoring changes in photocoagulation lesions. Some measurements and qualitative changes showed an adequate correlation between the OCT and histological findings.

Effects of Transfixation Pin Positioning on the Biomechanical Properties of Acrylic External Skeletal Fixators in a Fracture Gap Model.

OBJECTIVE: The aim of this study was to evaluate the biomechanical effects of transfixation pin positioning in acrylic columns of external skeletal fixators (ESF). STUDY DESIGN: Twenty-four type I acrylic ESF were built simulating a fracture gap-model. Transfixation pins were placed centric (n = 12) or eccentric at » of the column diameter (n = 12) in the acrylic columns. Six constructs from each group were subjected to axial compression and four-point bending tests. Stiffness, yield load and mode of failure were recorded. RESULTS: Stiffness was not influenced by centring (p = 0.373), but it was higher in four-point bending than in axial compression (p < 0.001). Pin positioning had no influence on the yield (p = 0.535) and failure loads (p = 0.715) in axial compression, nor on the yield load in bending (p = 0.135). Eccentric pin positioning decreased failure loads by 28% in bending (p < 0.001). CONCLUSION: Eccentric position of transfixation pins within the acrylic columns alters the biomechanical properties of type I ESF constructs. While acrylic offers several advantages, when forming the columns, frame strength will be optimized if pins are centrally located.

Benign ureteral obstruction in cats: Outcome with medical management.

BACKGROUND: Limited information is available regarding the outcome of medical management (MM) of benign ureteral obstruction in cats (BUO). HYPOTHESIS: Describe clinical characteristics and outcome of MM of BUO. ANIMALS: Seventy-two client-owned cats with 103 obstructed kidneys. METHODS: Medical records of cats diagnosed with BUO between 2010 and 2021 that received >72 hours of MM were retrospectively reviewed. Clinical data, treatment, and outcome were reviewed. Outcome was classified as success, partial success, or failure based on ultrasound findings. Factors associated with outcome were assessed. RESULTS: Seventy-two cats with 103 obstructed kidneys were enrolled. The causes of obstruction were uroliths in 73% (75/103), strictures in 13.5% (14/103), and pyonephrosis in 13.5% (14/103) of affected kidneys. Median serum creatinine concentration at presentation was 4.01 mg/dL (range, 1.30-21.3 mg/dL). Outcome after MM was considered a success in 30% (31/103), partial success in 13% (13/103), and failure in 57% (59/103) of kidneys. Success was reported in 23% (17/75) of kidneys with uroliths, 50% (7/14) with pyonephrosis, and 50% (7/14) with strictures. Median time to a successful outcome was 16 days (range, 3-115 days). Distal and smaller uroliths (median length, 1.85 mm) were significantly associated with success (P = .05 and P = .01, respectively). Median survival times were 1188 days (range, 60-1700 days), 518 days (range, 7-1812 days), and 234 days (range, 4-3494 days) for success, partial success, and failure, respectively. CONCLUSIONS AND CLINICAL IMPORTANCE: We found a higher success rate for MM of BUO than previously reported. Smaller distal uroliths (<1-2 mm) were more likely to pass.

Immunization of broiler chickens with five newly identified surface-exposed proteins unique to Clostridium perfringens causing necrotic enteritis.

Since the ban or reduction on the use of antibiotic growth promoters (AGPs) in commercial broiler chickens in many countries, avian necrotic enteritis (NE) caused by Clostridium perfringens has re-emerged as one of the biggest threats for the poultry industry worldwide. While the toolbox for controlling NE in the absence of antibiotics consists of a limited number of alternatives for which the overall effectiveness has yet proven to be suboptimal, an effective vaccine would represent the best control strategy for this often-deadly disease. Using a comparative and subtractive reverse vaccinology approach, we previously identified 14 putative antigenic proteins unique to NE-causing strains of C. perfringens. In the current work, the in silico findings were confirmed by PCR and sequencing, and five vaccine candidate proteins were produced and purified subsequently. Among them, two candidates were hypothetical proteins, two candidates were prepilin proteins which are predicted to form the subunits of a pilus structure, and one candidate was a non-heme iron protein. Western blotting and ELISA results showed that immunization of broiler chickens with five of these proteins raised antibodies which can specifically recognize both the recombinant and native forms of the protein in pathogenic C. perfringens.

VALIDATION OF ENZYME-LINKED IMMUNOSORBENT ASSAY TECHNIQUES TO MEASURE SERUM DEHYDROEPIANDROSTERONE (DHEA) AND DHEA-S IN NARWHALS (MONODON MONOCEROS).

Narwhals (Monodon monoceros) are increasingly exposed to anthropogenic disturbances that may increase their stress levels with unknown consequences for the overall population dynamics. The validation and measurement of chronic stress biomarkers could contribute toward improved understanding and conservation efforts for this species. Dehydroepiandrosterone (DHEA) and its sulfated metabolite DHEA-S are collectively referred to as DHEA(S). Serum DHEA(S) concentrations combined in ratios with cortisol [cortisol/DHEA(S)] have been shown to be promising indicators of chronic stress in humans, domestic animals, and wildlife. During field tagging in 2017 and 2018 in Baffin Bay, Nunavut, Canada, 14 wild narwhals were sampled at the beginning and end of the capture-tagging procedures. Serum DHEA(S) were measured with commercially available competitive enzyme-linked immunosorbent assays (ELISA) developed for humans. A partial validation of the ELISA assays was performed by the determination of the intra-assay coefficient of variation, confirmation of the DHEA(S) dilutional linearity, and the calculation of the percentage of recovery. Mean values (nanograms per milliliter ± standard error of the mean) of narwhal serum cortisol, DHEA(S), and cortisol/DHEA(S) ratios, at the beginning and at the end of handling, respectively, are reported (cortisol = 30.74 ± 4.87 and 41.83 ± 4.83; DHEA = 1.01 ± 0.52 and 0.99 ± 0.50; DHEA-S = 8.72 ± 1.68 and 7.70 ± 1.02; cortisol/DHEA = 75.43 ± 24.35 and 84.41 ± 11.76, and cortisol/DHEA-S = 4.16 ± 1.07 and 6.14 ± 1.00). Serum cortisol and cortisol/DHEA-S were statistically higher at the end of the capture (P= 0.024 and P= 0.035, respectively). Moreover, serum cortisol at the end of handling was positively correlated to total body length (P = 0.042) and tended to be higher in males (P = 0.086). These assays proved easy to perform, rapid, and suitable for measuring serum DHEA(S) of narwhals and that calculated cortisol/DHEA(S) are potential biomarkers for chronic stress in narwhals and possibly other cetaceans.

Clinicopathological findings of FeLV- positive cats at a secondary referral center in Florida, USA (2008-2019).

OBJECTIVES: The aim of this study was to describe the seroprevalence, presenting complaint, clinicopathological changes, co-morbidities and outcomes of feline leukemia virus positive cats presented to a specialty referral center in Florida, USA. METHODS: In this retrospective study, medical records of 8050 cats presented to a private referral center from August 2008 to September 2019 were reviewed. Inclusion criteria required was a positive result for feline leukemia virus by point-of-care antigen testing or immunofluorescence assay. RESULTS: Forty-one cases met the inclusion criteria. Of 2002 cats that were tested, 41 cats (2%) met the inclusion criteria. One cat had a negative point of care antigen test result and positive bone marrow IFA result. The mean age at diagnosis was 9 years. The main reasons for presentation were abnormal complete blood cell count results (35%), followed by pleural effusion (18%), and anorexia (15%). The most common laboratory abnormalities included anaemia (71%), of which 74% had a nonregenerative anemia, thrombocytopenia (52%), elevated aspartate aminotransferase (50%), hyperbilirubinemia (35%), and hypokalemia (35%). Seven percent of cats (3/41) were also positive for feline immunodeficiency virus. The most common diagnoses were neoplasia (76%) and bone marrow disorders (12%). Cats with neoplasia were significantly younger. Survival to discharge was 88%. CONCLUSION AND RELEVANCE: Results of this study show that feline leukemia virus is uncommon in secondary referral center, even if this represents a population of unhealthy cats. The most common associated diagnosis was neoplasia, which was more likely to be seen in younger cats (< 4 years of age). The mean age of cats positive for feline leukemia virus was also older than previously published data. These findings support the current guidelines which indicate that cats presented with clinical illness should be tested for FeLV at the time of presentation.

Linking genetic, morphological, and behavioural divergence between inland island and mainland deer mice.

The island syndrome hypothesis (ISH) stipulates that, as a result of local selection pressures and restricted gene flow, individuals from island populations should differ from individuals within mainland populations. Specifically, island populations are predicted to contain individuals that are larger, less aggressive, more sociable, and that invest more in their offspring. To date, tests of the ISH have mainly compared oceanic islands to continental sites, and rarely smaller spatial scales such as inland watersheds. Here, using a novel set of genome-wide SNP markers in wild deer mice (Peromyscus maniculatus) we conducted a genomic assessment of predictions underlying the ISH in an inland riverine island system: analysing island-mainland population structure, and quantifying heritability of phenotypes thought to underlie the ISH. We found clear genomic differentiation between the island and mainland populations and moderate to high marker-based heritability estimates for overall variation in traits previously found to differ in line with the ISH between mainland and island locations. FST outlier analyses highlighted 12 loci associated with differentiation between mainland and island populations. Together these results suggest that the island populations examined are on independent evolutionary trajectories, the traits considered have a genetic basis (rather than phenotypic variation being solely due to phenotypic plasticity). Coupled with the previous results showing significant phenotypic differentiation between the island and mainland groups in this system, this study suggests that the ISH can hold even on a small spatial scale.