Brachycephalic syndrome (BS) in dogs is characterized by the combination of primary and secondary upper respiratory tract abnormalities and may result in significant upper airway obstruction. It can trigger inspiratory dyspnea, culminating in secondary respiratory distress, soft tissue edema, upper airway obstruction, turbulent airflow, inspiratory noise, and even death. These changes lead to increased resistance of the air passages, which can cause elevation of pulmonary pressure and clinical manifestations attributable to pulmonary hypertension. The consequence is right-sided cardiac remodeling (Cor pulmonale) with possible progression to right congestive heart failure. To investigate the effects of BS on the cardiovascular system, 28 animals were recruited for a prospective study and assigned to either the Brachycephalic Group (BG), composed of 22 French bulldogs with BS or the Control Group (CG), which was composed of 6 healthy Beagle dogs. All animals underwent a detailed physical examination, as well as laboratory analyses, electrocardiography, echocardiography, chest radiography and indirect measurement of systemic arterial blood pressure. The most relevant finding was a lower PaO2 (90.6±12.9mmHg) in BG as compared to CG (104.9±5.2), (p≤0.05), possibly attributable to hypoventilation due to anatomical alterations.

Little information is available comparing the i-STAT and the YSI 2300 Stat Plus devices to determine the lactate concentration [Lac] in dogs undergoing intense exercise. The reproducibility of the YSI 2300 for quantifying the [Lac] in canine blood [Lac]b and plasma [Lac]p samples has been observed. In addition, the i-STAT handheld device was used to quantify [Lac] in dogs subjected to exercise, and the results were compared with that of YSI 2300. Venous blood samples of Beagle and American Pit Bull Terrier dogs were obtained during an intense exercise training on a treadmill. [Lac]p and [Lac]b were quantified using the YSI 2300 instrument to determine the reproducibility of the results. A total of 52 specimens were compared for both plasma and whole blood. For comparing the devices (YSI 2300 vs i-STAT), 96 samples were used. Ordinary least products regression, the correlation coefficient, and Bland-Altman plots were used to assess the agreement of using the i-STAT device. The relationship between duplicate measurements of both [Lac]b and [Lac]p by YSI 2300 was strong (r=0.99). A correlation between the data obtained using the i-STAT and YSI 2300 instruments was observed for both the [Lac]p (r=0.97) and [Lac]b (r=0.88). The i-STAT exhibited a small constant bias (-0.25 mmol/l) compared to YSI 2300 ([Lac]b). There were proportional biases of 0.89 mmol/l for [Lac]p and 1.22 mmol/l for [Lac]b when using YSI 2300 vs i-STAT. We confirmed the reproducibility of the YSI 2300 for canine lactate blood/plasma samples. The results obtained by the i-STAT and YSI 2300 analyser were highly correlated, but a small constant bias was observed between them. The i-STAT device can be used in clinical evaluations, and it is also adequate for designing and monitoring fitness programmes.

The structure and function of crocodilian lungs are unique compared with those of other reptiles. We examined the extent to which this and the semi-aquatic lifestyle of crocodilians affect their respiratory mechanics. We measured changes in intratracheal pressure in adult and juvenile caiman (Caiman yacare) during static and dynamic lung volume changes. The respiratory mechanics of juvenile caiman were additionally measured while the animals were floating in water and submerged at 30, 60 and 90 deg to the water's surface. The static compliance of the juvenile pulmonary system (2.89±0.22 ml cmH 2 O −1 100 g −1) was greater than that of adults (1.2±0.41 ml cmH 2 O −1 100 g −1), suggesting that the system stiffens as the body wall becomes more muscular and keratinized in adults. For both age groups, the lungs were much more compliant than the body wall, offering little resistance to air flow (15.35 and 4.25 ml cmH 2 O −1 100 g −1 for lungs, versus 3.39 and 1.67 ml cmH 2 O −1 100 g −1 for body wall, in juveniles and adults, respectively). Whole-system dynamic mechanics decreased with increasing ventilation frequency (f R), but was unaffected by changes in tidal volume (V T). The vast majority of the work of breathing was required to overcome elastic forces; however, work to overcome resistive forces increased proportionally with f R. Work of breathing was higher in juvenile caiman submerged in water at 90 deg because of an increase in work to overcome both elastic and flow resistive forces. The lowest power of breathing was found to occur at high f R and low V T for any given minute ventilation (V E) in caiman of all ages.

RESUMO.-[Exame eletrocardiográfico em pacas fême-as (Cuniculus paca).]Considerando a limitada informação sobre a fisiologia cardíaca em roedores neotropicais e a importância desta informação para estudos fisiopatológicos e de conservação desta espécie, objetivou-se com este estudo avaliar a atividade elétrica cardíaca de pacas saudáveis mantidas em cativeiro, sob restrição química, devido à natureza selvagem destes animais. Onze fêmeas adultas foram avaliadas clinicamente e por meio do hemograma e testes bioquímicos no intuito de descartar qualquer co-morbidade associada. Cada animal foi submetido a três períodos experimentais a cada 15 dias. Após a restrição química com Considering the limited physiological information available on neotropical rodents and the importance of this information for pathophysiological and conservation studies of these species, the aim of this study was to evaluate the cardiac electric physiology of healthy captivity spotted pacas (Cuniculus paca) under chemical restraint, due to wild nature of these animals. Eleven adult female pacas were evaluated by blood count and biochemical dosage to rule out any associate disease. Each animal was evaluated in three periods every 15 days. After chemical restraint with intramuscular midazolam 0.5mg/kg and ketamine 25mg/kg, animals were subjected to a computerized electrocardiogram, where bipolar (DI, DII and DIII) and augmented unipolar leads (aVR, aVL, aVF) were obtained. Descriptive statistics were calculated for each parameter and built the confidence interval (CI) at significance level of 95%. The electrocardiographic examination was performed without difficult. ECG tracing in DII represents a QRS complex with positive polarity, preceded by a P wave of the same polarity and proceeded by T wave of variable polarity. Heart rate mean was 150±17 bpm, and cardiac electrical axis 33.4±21.9°. All animals showed sinusal rhythm. The ECG recording technique associated with chemical restraint was well tolerated, allowing quick acquisition of reliable ECG tracings with high repeatability, which produced sufficient results to determine the heart rhythm and suggest measures of ECG complexes duration and amplitude.

ResumenLas membranas biológicas se emplean como implantes en cirugía veterinaria reconstructiva con el objetivo de restablecer la función y la estructura de tejidos dañados. Diversos tejidos obtenidos de animales, conservados por diferentes técnicas e implantados en receptores de la misma o de diferente especie, permiten reparar heridas en las que es evidente la extensa pérdida tisular o la imposibilidad de inducir cicatrización por primera intención. Aunque las bondades de las membranas biológicas son mayores que sus desventajas, su uso en la rutina clínica y quirúrgica no es frecuente, en gran parte por el desconocimiento de sus características, manipulación e implantación. La presente revisión pretende recopilar los aspectos generales que envuelven las membranas biológicas, desde su obtención hasta las posibles complicaciones de su uso, a través de estudios experimentales y reportes de caso relatados con anterioridad, e incentivar su uso como biomaterial de implante en defectos anatómicos, heridas traumáticas, postoperatorios oncológicos y traumas en general.Palabras clave: animales, cirugía, membranas biológicas, reconstrucción, reparación. Biological membrane implants in veterinary reconstructive surgery: Basic aspects and conservation methods AbstractBiological membranes are used as implants in veterinary reconstructive surgery in order to restore the function and structure of damaged tissues. Various tissues from animals, kept by different techniques and implanted in recipients of the same or different species, help repair wounds where extensive tissue loss or the inability to scarring is evidenced. Although the benefits of biological membranes outweigh their disadvantages, their use in clinical and surgical routines is rare, largely due to ignorance of their characteristics, handling and implantation. The present article aims to review general aspects on biological membranes, from procurement to possible complications of their use, through experimental studies and previously reported cases, and to encourage their use as a biomaterial implant in case of anatomical defects, traumatic wounds, oncological postoperative care, and traumas in general.