The use of agitated saline as contrast agent in a contrast-enhanced cystosonography for detection of urinary bladder rupture in animal cadavers.

OBJECTIVE: To determine the value of microbubble contrast cystosonography in the diagnosis of bladder rupture in animals. DESIGN: Prospective, method comparison study from November 2019 to October 2020. SETTING: University teaching hospital. ANIMALS: Thirty-four ethically sourced cadavers of dogs, rats, and rabbits. INTERVENTIONS: In a prospective and blinded study, the cadavers were divided into 2 randomized groups: with bladder rupture (CR), and without bladder rupture (SR). Urinary catheterization was performed in all cadavers. Through the urethral catheter, bladders in CR group were ruptured using a rigid stainless steel guide wire. Microbubble contrast was infused into the bladder through the urethral catheter, while a single, blinded observer sonographically assessed the bladder. The time to diagnosis and the number of attempts needed for diagnosis were recorded. MEASUREMENTS AND MAIN RESULTS: The study included cadavers of 16 female Wistar rats, 6 female dogs, 11 male dogs, and 1 male rabbit. Time to diagnosis in dogs (2.25 ± 0.91 min) was statistically higher when compared to rats (1.15 ± 0.75 min; P = 0.03). Of the 34 cases, incorrect diagnosis of bladder rupture was made in only 2 dogs (6%), indicating a diagnostic sensitivity of 88.88%, specificity of 100%, and an accuracy of 94%. The positive predictive value was 1 and the negative predictive value was 0.9. CONCLUSIONS: Our study showed that the described method is accurate, sensitive, and specific for the detection of bladder rupture in animal cadavers of different species, size, and sex.

Sedative effects of an intramuscular or intranasal combination of sufentanil and midazolam in New Zealand White rabbits.

OBJECTIVE: To evaluate the sedative effects of a combination of sufentanil and midazolam administered intramuscularly (IM) or intranasally (IN) prior to induction of anesthesia with propofol in New Zealand White rabbits. STUDY DESIGN: Prospective, randomized, crossover, experimental study. ANIMALS: A total of 11 adult New Zealand White rabbits. METHODS: Sufentanil (0.5 µg kg-1) and midazolam (2 mg kg-1) were administered to rabbits via IM or IN route. The righting reflex was assessed, and sedation was scored. Heart rate, respiratory rate (fR) and temperature were recorded prior to treatment administration and after loss of the righting reflex. RESULTS: Measured variables remained within normal physiologic ranges for all rabbits. The only statistically significant change was for fR, which was significantly lower after sedation for both routes. The time to loss of righting reflex was 14.8 ± 6.5 and 12.5 ± 7.4 minutes and sedation scores were 6 (4-8) and 7 (6-8) for IM and IN routes, respectively, with no difference between treatments. No adverse effects were observed during the experimental period. CONCLUSIONS AND CLINICAL RELEVANCE: Sufentanil combined with midazolam administered either IM or IN resulted in moderate to deep sedation in New Zealand White rabbits at the dose rates studied.

Novel Anaplasmataceae agents Candidatus Ehrlichia hydrochoerus and Anaplasma spp. Infecting Capybaras, Brazil.

We amplified Ehrlichia and Anaplasma DNA from Amblyomma dubitatum tick-infested capybaras (Hydrochoerus hydrochaeris) in southern Brazil. Sequencing of 16S rRNA, sodB, and groEL indicated a novel Ehrlichia species, and sequencing of 16S rRNA from 2 capybaras indicated a novel Anaplasma species. The tick vectors remain unknown.

'Candidatus Mycoplasma haematohydrochoerus', a novel hemoplasma species in capybaras (Hydrochoerus hydrochaeris) from Brazil.

Three different species of hemoplasmas have been described in rodents, Mycoplasma coccoides, 'Candidatus Mycoplasma haemomuris' and 'Candidatus Mycoplasma haemosphiggurus'. Additionally, potentially novel hemoplasma species have been detected in wild rodents from Brazil, including capybaras (Hydrochoerus hydrochaeris). Capybaras are the largest rodent in the world and are well adapted to live within close proximity to humans, which increases the risk to spread of zoonotic pathogens. Herein, we investigate the occurrence and genetic diversity of hemoplasmas infecting free-ranging capybaras from southern Brazil. Blood samples and ticks from 17 capybaras were collected. Packed cell volume and total plasma protein were measured, DNA was extracted, and further screened by species-specific and pan-hemoplasma PCR assays targeting the 16S rRNA gene of hemoplasmas. Sixteen out of 17 (94.12%; 95% CI: 73.02-98.95%) were anemic. Only one young female was hypoproteinemic. All capybaras were infested by adults and nymphs of Amblyomma dubitatum ticks. Using the PCR assay targeting the 16S rRNA gene of M. coccoides, 13/17 (76.47%; 95% CI: 52.74-90.44%) capybaras were positive for hemoplasmas. When DNA samples were tested by the pan-hemoplasma PCR, 16/17 (94.12%; 95% CI: 73.02-98.95%) animals were positive. One out of 11 (9.09%) adult ticks salivary glands tested positive for hemoplasma by the pan-hemoplasma PCR assay. Sequencing and phylogenetic analysis of the 16S and 23S rRNA gene fragments confirmed that animals were infected by a novel hemotropic Mycoplasma sp. previously reported in capybaras from Brazil. Additionally, sequencing and phylogenetic analysis of the 23S rRNA gene from three hemoplasma-positive capybaras samples from a previous study performed in midwestern Brazil also confirm our findings. Based on phylogenetic and Neighbor-Net network analysis of the 16S rRNA and 23S rRNA genes, the name 'Candidatus Mycoplasma haematohydrochoerus' is proposed for this novel organism.

Evaluation of injection volumes for the transversus abdominis plane block in dog cadavers: a preliminary trial.

OBJECTIVE: To evaluate staining of nerve branches after the injection of different volumes during ultrasound-guided transversus abdominis plane (TAP) block in dog cadavers. STUDY DESIGN: Prospective randomized study. ANIMALS: A total of 15 frozen/thawed adult dog cadavers. METHODS: Hemiabdomens were randomly allocated to one of four groups. In groups G0.3, G0.6 and G1.0, ropivacaine-methylene blue solution (0.3, 0.6 and 1.0 mL kg-1 in seven, eight and eight hemiabdomens, respectively) was injected at the midpoint between the iliac crest and the last rib at the height of the shoulder. In group G0.3×2 (seven hemiabdomens), two injections (0.3 mL kg-1) were performed, caudal to the last rib and cranial to the iliac crest at the same height. Total time for injection was recorded; after 30 minutes, cadavers were dissected and spread of dye was evaluated. RESULTS: Accuracy of injection site was 80% and injection time was 71 (48-120) seconds for all groups together. Craniocaudal spread was 6.4 ± 1.6, 9.1 ± 2.6, 11.4 ± 2.3 and 11.2 ± 3.8 cm for G0.3, G0.6, G1.0 and G0.3×2, respectively [G0.3 to G0.3×2 (p = 0.044) and G1.0 (p = 0.034)]. There was no difference in dorsoventral spread among groups. Number of ventral nerve branches stained was 3 (2-4), 3 (2-4), 3 (3-4) and 3 (2-4) for G0.3, G0.6, G1.0 and G0.3×2, respectively, including nerve branches from twelfth thoracic to third lumbar (L3) in different proportions among groups. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that a single-injection TAP block, using 0.3 mL kg-1, stains comparable number of nerve branches as higher volumes or two-point injection. Despite the volume or technique, consistent staining of the innervation of the caudal abdomen (L1-L3) was observed. Additional cadaveric studies are necessary to identify the optimal technique for complete abdominal wall staining.

Normal sonographic anatomy of the abdomen of coatis (Nasua nasua Linnaeus 1766).

BACKGROUND: The use of ultrasound in veterinary medicine is widespread as a diagnostic supplement in the clinical routine of small animals, but there are few reports in wild animals. The objective of this study was to describe the anatomy, topography and abdominal sonographic features of coatis. RESULTS: The urinary bladder wall measured 0.11 ± 0.03 cm. The symmetrical kidneys were in the left and right cranial quadrant of the abdomen and the cortical, medullary and renal pelvis regions were recognized and in all sections. The medullary rim sign was visualized in the left kidney of two coatis. The liver had homogeneous texture and was in the cranial abdomen under the rib cage. The gallbladder, rounded and filled with anechoic content was visualized in all coatis, to the right of the midline. The spleen was identified in the left cranial abdomen following the greater curvature of the stomach. The parenchyma was homogeneous and hyperechogenic compared to the liver and kidney cortex. The stomach was in the cranial abdomen, limited cranially by the liver and caudo-laterally by the spleen. The left adrenal glands of five coatis were seen in the cranial pole of the left kidney showing hypoechogenic parenchyma without distinction of cortex and medulla. The pancreas was visualized in only two coatis. The left ovary (0.92 cm x 0.56 cm) was visualized on a single coati in the caudal pole of the kidney. The uterus, right adrenal, right ovary and intestines were not visualized. CONCLUSIONS: Ultrasound examination of the abdomen of coatis may be accomplished by following the recommendations for dogs and cats. It is possible to evaluate the anatomical and topographical relationships of the abdominal organs together with the knowledge of the peculiarities of parenchymal echogenicity and echotexture of the viscera.

Conjunctival effects of canine distemper virus-induced keratoconjunctivitis sicca.

OBJECTIVE: This study compared the histopathology of canine distemper virus (CDV)-induced keratoconjunctivitis sicca (KCS) to non-infectious KCS in conjunctival tissues. ANIMALS STUDIED: Forty mongrel dogs were assigned to three distinct groups: (i) non-infectious KCS (G1, n = 10), (ii) CDV-induced KCS (G2, n = 20), and (iii) healthy animals without any ocular alterations (G3, n = 10). PROCEDURE: IgG titers and physical and ophthalmic examinations (e.g. Schirmer tear test [STT], tonometry, biomicroscopy, indirect biomicroscopy, and fluorescein test) were performed on all dogs. Conjunctival biopsies were collected and examined microscopically. RESULTS: Non-infectious and CDV-induced KCS demonstrated similar histopathological changes. Both types of KCS correlated with low STT, conjunctival hyperemia, mucopurulent ocular discharge, predominant lymphoplasmacytic infiltration, and acantholysis and keratinization of the ocular surface. G1 had lower conjunctival goblet cell counts than G3. Inclusion bodies were sporadically found in conjunctival samples of dogs from G2. The severity of ocular lesions in G1 and G2 did not correlate with the histopathological findings. CONCLUSIONS: Dogs with non-infectious and CDV-induced KCS had very similar conjunctival histopathology. Our findings suggest that the pathophysiology of CDV-induced KCS is likely to be the same as non-infectious KCS, that is, a result of lacrimal deficiency and inflammation of the ocular surface.