Evaluation of skin sensitivity in dogs bearing allergic dermatitis to standardized allergenic extract of house dust and storage mites

The objective of the study was to evaluate whether allergenic extracts of five house dust and storage mite species standardized for humans might be used for the diagnosis of canine atopic dermatitis (CAD). Extracts of Dermatophagoides pteronyssinus (Pyroglyphidae), D. farinae (Pyroglyphidae), Blomia tropicalis (Glycyphagidae), Lepidoglyphus destructor (Glycyphagidae) and Tyrophagus putrescentiae (Acaridae) were evaluated by intradermal testing in 20 healthy dogs (control) and 25 dogs with allergic dermatitis. A significant difference in the response was observed between the two groups (p<0.05). Only one dog (5%) in the control group reacted to the intradermal test, whereas 14 dogs (56%) in the allergic group were positive for at least one extract (odds ratio = 24.2). Most of the positive reactions observed in the allergic group occurred against the extracts of T. putrescentiae or L. destructor, each inducing reactions in 10 dogs (40%). D. farinae, D. pteronyssinus e B. tropicalis extracts induced reactions in 7 (28%), 3 (12%) and 3 (12%) dogs, respectively. The allergenic extracts standardized for humans evaluated in the present study may be used as a tool to complement the diagnosis of the disease, as well as to select potential allergen candidates for allergen-specific immunotherapy.

Treatment of ununited anconeal process in 8 dogs by osteotomy and dynamic distraction of the proximal part of the ulna

A surgical technique for the treatment of ununited anconeal process in dogs treated by osteotomy and dynamic distraction of the proximal part of the ulna using a linear external skeletal fixator was evaluated. In all cases the osteotomy was distracted 1mm each day after the surgery until desired distraction had been achieved. Eight dogs and 9 joints diagnosed with ununited anconeal process were treated. The success of the procedure was determined by comparing clinical signs of lameness and degree of arthrosis at the time of diagnosis to 6 months after the surgical intervention. Radiographic union occurred in 88.9% of the affected joints between 21 and 42 days after the surgical procedure. Clinically, six elbows were classified as good, two as satisfactory and one as unsatisfactory. Six months after surgery two elbows had no arthrosis, one had Grade 1, two Grade 2 and one Grade 3. It is concluded the combination of ulnar osteotomy and dynamic distraction of the olecranon by a linear external skeletal fixator is a feasible procedure for the treatment of ununited anconeal process in dogs.

Technological development of 40mg furosemide tablets: equivalence and bioavaibility study in dogs

Furosemide (40mg) was administered to 20 street dogs, 10 males and 10 females, in two different pharmaceutical forms: (1) compressed furosemide 40mg formulated at the Federal University of Pernambuco (UFPE-tablet), and (2) a commercial formulation with equal bioequivalence produced by the Laboratory for Pharmaceutical Technology of Pernambuco State (LAFEPE), the LAFEPE-furosemide. The study aimed to evaluate the kinetics of dissolution of the UFPE-tablet in order to analyze the behavior of bioavailability of the best formulation for veterinary use. The plasmatic concentrations of furosemide for the determination of parameters of pharmacological kinetics were analyzed by high-performance liquid chromatographic method (HPLC). The in vitro study accomplished through physiochemical analyses demonstrated that the formulas of the furosemide tablets attained the pharmaceutical requirements in agreement with USP 23 and the Brazilian Pharmacopoeia. The evaluation accomplished in dogs with UFPE-tablets given in only dose demonstrated uniformity in blood levels indicating stability in maintenance of the pharmaceutical formulation and efficiency in absorption of the active compound. These values are not significantly different in relation to the 5% confidence limit. Regarding maximum concentration (Tmax) time and global bioavaibility assessed by AUC means, there were no considerable differences as well. UFPE-furosemide displayed 743.492µg/mL.h as AUC average value whereas LAFEPE-furosemide had an average of 537.284µg/mL.h.

Total intravenous anaesthesia with propofol-racemic ketamine and propofol-S-ketamine: a comparative study and haemodynamic evaluation in dogs undergoing ovariohysterectomy

Total intravenous anaesthesia (TIVA) with propofol and ketamine proved to be very satisfactory from a clinical point of view. This blind randomised controlled trial was designed to compare induction and maintenance of anaesthesia under continuous infusion of propofol-racemic ketamine (PRK) with that of propofol-S-ketamine (PSK) and evaluate their haemodynamic, metabolic and ventilatory effects. Seven female dogs undergoing ovariohysterectomy were involved in each group. Anaesthesia was induced: in Group PRK, with propofol (4.0mg kg-1) and racemic ketamine (2.0mg kg-1) intravenous (i.v.), followed by i.v. infusion of propofol (initial dose of 0.5mg kg-1 min-1) and racemic ketamine (0.2mg kg-1 min-1); in Group PSK, with propofol (4.0mg kg-1) and S-ketamine (1.0 mg kg¹) i.v., followed by i.v. infusion of propofol (initial dose of 0.5mg kg-1 min-1) and S-ketamine (0.1mg kg-1 min-1). Parameters were assessed before anaesthesia and in 6 time points after induction. In both groups, heart rate increased significantly at all time points. There was a slight decrease in systemic blood pressure, cardiac output and cardiac index in both groups. The systolic index decrease significantly and intense respiratory depression was observed in all groups, making assisted ventilation necessary.

Factors associated with the prevalence of Otodectes cynotis in an ambulatory population of dogs

The objective was to evaluate the factors associated with the prevalence of Otodectes cynotis infestations in dogs assisted at the Dermatology Service of the Veterinary Hospital, Universidade Federal Rural do Rio de Janeiro. A total of 250 dogs were examined through direct smear of ear samples using a stereoscopic microscope, for the parasitological diagnostic. All dog owners were interviewed and data regarding the animals and their environments were individually recorded. Mite infestation was observed in 15 animals, with a prevalence of 6%. The variables were tested regarding their association with the mites, using the χ2 test and, when appropriate, the Fisher exact test. There were no evidences that age (p = 0,20), sex (p = 0,31), breed (p = 0,50), shape of ear (p = 0,66), type (p = 0,19) and length of hair (p = 0,14) and contact with other animals (p = 0,06) could act as potential risk factors for O. cynotis infestation. However, living environment (p = 0,03) and frequency of environmental cleaning (p = 0,005) may facilitate the infestation. The occurrence of pruritus was associated to the presence of mites (p<0,001), suggesting to be an effect of the parasitism.

Morphological analysis of the corneal endothelium in eyes of dogs using specular microscopy

Both healthy eyes of 10 six-year-old male and female mongrel dogs were studied. With a contact specular microscope the corneal endothelium was examined. Endothelial cells were analyzed in the central and peripheral cornea. Morphological analysis with regard to polymegathism and pleomorphism was performed. Three images of each region with at least 100 cells were obtained. The analysis showed that polygonal cells formed a mosaic-like pattern uniform in size and shape. The predominant number of cells was hexagonal. The polymegathism index was 0.22. The study demonstrates that the morphology of the normal corneal endothelial cells of dogs is similar to that found in the human cornea.

An enzyme-linked immunosorbent assay (ELISA) for the detection of IgM antibodies against Leishmania chagasi in dogs

Visceral leishmaniasis is an emergent zoonosis with an increasing number of new cases in Brazil where the domestic dog is an important parasite reservoir in the infectious cycle of Leishmania chagasi. An enzyme-linked immunosorbent assay (ELISA), based upon the use of a total soluble antigenic preparation of L. chagasi, was adapted for the detection of IgM antibodies in the serum of infected dogs. Optimal dilutions of the antigen, using positive and negative reference sera, were determined by checkboard titrations. The specificity and sensitivity of the ELISA were 100 %. A total of 110 serum samples were taken from dogs in Belo Horizonte, Minas Gerais, Brazil, and examined for anti-L. chagasi IgM antibody by ELISA and indirect fluorescent antibody test (IFAT). About 25% (n=27) of all the dogs tested were found serologically positive for L. chagasi by IFAT, while 89.09% (n=98) were seropositive by ELISA. The results obtained by ELISA and IFAT were significantly different (P<0.01). The combined use of ELISA and IFAT is recommended in order to enable veterinary services to more efficiently detect canine visceral leishmaniasis.

Outflow occlusion for circulatory arrest in dogs

The purpose of this study was to evaluate the possibility of producing circulatory arrest by occlusion of the pulmonary trunk as an alternative to the venous inflow occlusion through the left hemithorax. Eight healthy mongrel dogs were divided in two groups. Group I underwent 4 minutes of outflow occlusion and Group II was submitted to 8 minutes of circulatory arrest. Outflow occlusion was performed through left thoracotomy and pericardiotomy by passing a Rumel tourniquet around the pulmonary trunk. Physical examination, electrocardiography, echocardiography, blood gas analyses, hemodynamic, and oxygen transport variables were obtained before and after the procedure. The dogs from Group I did not have any clinical, electrocardiographic, echocardiographic, or hemo-dynamic abnormalities after anesthetic recover. In the Group II, only one dog survived, which had no clinical, electrocardiographic, or echocardiographic abnormalities. In this last dog, just after releasing the occlusion, it was detected increases in the following parameters: heart rate (HR), systolic, diastolic and mean arterial blood pressure (SAP; DAP; MAP), pulmonary artery pressure (PAP), pulmonary wedge pressure (PWP), central venous pressure (CVP), cardiac output (CO), systolic index (SI), cardiac index (CI), left and right ventricular stroke work (LVSW; RVSW), oxygen delivery index (DO2), oxygen consumption index (VO2), and oxygen extraction (O2 ext). Moreover, the oxygen content of arterial and mixed venous blood (CaO2; CvO2), and the arterial and mixed venous partial pressure of oxygen (PaO2; PvO2) were decreased 5 minutes after circulatory arrest. Outflow occlusion is a feasible surgical procedure for period of 4 minutes of circulatory arrest.

Evaluation of left ventricular diastolic echocardiographic parameters in healthy dogs by pulsed-wave Doppler

Left ventricular diastolic dysfunction plays an important role on heart failure progression. In order to obtain additional reference values of left ventricular diastolic parameters and investigate influence of common variables, peak E wave (peak E), peak A wave (peak A), E/A ratio (E/A), E wave deceleration time (EDT) and isovolumic relaxation time (IRVT) were studied in 40 clinically healthy dogs, by pulsed wave Doppler. The following values were obtained: peak E = 0.747 ± 0.117 m/s, peak A = 0.487 ± 0.062 m/s, E/A = 1.533 ± 0.198, EDT = 88.7 ± 9.2 ms and IRVT = 0.080 ± 0.009 s. Some parameters were influenced by heart rate (peak E, peak A and IRVT), by age (peak A and E/A) and by body weight (TRIV). Gender influence was absent. Values obtained can be used as reference for canine specimens but its interpretation should consider on the influence of related variables.

Laparoscopic versus open splenectomy in dogs

In the last few years, the use of laparoscopy in veterinary medicine has expanded and consequently so was the need for studies that establish the advantages, disadvantages and possible complications of each procedure. The purpose of the current study was to describe a laparoscopic splenectomy technique and the alterations due to this access, and compare it to the open procedure in dogs. A total of 15 healthy female mongrel dogs were used, with mean weight of 17.4±2.5kg. The animals were distributed into three groups: Group IA of open splenectomy (laparotomy) using double ligation of the vessels of the splenic hilum with poliglicolic acid, Group IB of open splenectomy (laparotomy) with bipolar electrocoagulation of the splenic hilum, and Group II of laparoscopic access with bipolar electrocoagulation of the splenic hilum. Operative time, blood loss, size of incisions, complications during and after surgery were evaluated. Other parameters included pain scores, white blood cell (WBC) counts and postoperative serum concentrations of alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatine kinase (CK), C-reactive protein (CRP), glucose and cortisol. No differences were found in the evaluation of parameters between both open splenectomy techniques employed. Laparoscopic access presented significant differences (p<0,05) when compared with open surgery: Longer operative time, smaller abdominal access, decrease in blood loss, lower concentrations of CRP, higher levels of CK and ALP, and lower scores in the pain scale. Laparoscopic surgery showed fewer complications of the surgical wound. No significant differences were observed between groups in the postoperative temperature, WBC, ALT, cortisol and glucose concentrations. In conclusion, the laparoscopic technique is useful for splenectomy in dogs, being advantageous in terms of blood loss, surgical stress and surgical wounds. However, it expends more operative time and causes transitory increase in hepatic and muscular enzymes.

Chorion biopsy in mongrel dogs

With the great development of the gestational studies in all of the species, we noticed the necessity of adaptations of these techniques for prenatal diagnosis in dogs. Based on this, we studied the feasibility of chorion biopsy guided by ultrasound. Our results demonstrated accuracy on the sex determination being 2 males and 12 females, as well as it would be possible to identify chromosome alteration due to the quality of samplings. Sex determination was accomplished with the identification of Y gene chromosomes in PCR technique. After the collection, fragments were prepared for light microscopy studies and revealed fetal chorion tissue, blood colloid and erythrocyte. In the whole material we found hemosiderin impregnations due to the hemolysis and to the residue of blood of the placental marginal hematomes. The submitted female dogs to this technique demonstrated normal puppy births without death.

Clinical characterization of chronic chagasic cardiomyopathy in dogs

On the American continent, almost 15 million people are affected by Chagas disease, resulting in important economic and social damages. Dogs are considered to be an excellent experimental model to study Chagas' disease; as a result, in this research, the characterization of cardiovascular abnormalities was performed in dogs experimentally infected with Trypanosoma cruzi (the Colombian strain) that were at chronic stage. Thirteen adult female dogs were evaluated by electrocardiographic, echocardiographic, hematological and biochemical analyses in the chronic phase. For the electrocardiographic studies, respiratory sinus arrhythmia was the predominant rhythm during the entire research period (49.55% to 67%), with a low prevalence of right bundle branch block (0-13%) and first-degree atrioventricular block (0-14%). The spectral Doppler echocardio-graphy showed E and A mitral wave reversal (0.71±0.17), confirming the diastolic dysfunction present in all dogs. An increase in the enzymes activities was detected in the serum analysis, indicating myocardial injury by the infection. Six dogs died during the follow-up. In this way, the clinical characterization of experimentally infected dogs, as described here, increases the knowledge and allows for recognition of the behavioural modifications present in Chagas' disease in affected dogs.

A and B mode ultrasonography in preoperative evaluation of lens and posterior segment of dogs eyes with cataract

Ultrasonography of the lens and posterior segment is an indispensable step in the preoperative evaluation of dogs with cataracts, since ophthalmoscopy is not feasible when there is opacification of the lens. This study evaluated the echographic conditions of cataractous lens and fundus of the eye in dogs affected by cataracts. The study was conducted in 30 dogs (56 eyes), 10 males and 20 females, with different types of cataracts at different stages of development. Echography in A and B modes, simultaneously, was carried out for the examination of the lens and posterior segment. The examinations revealed anterior cortical, posterior cortical and nuclear cataract in 12 eyes (21.4%), anterior cortical, posterior cortical, nuclear and posterior capsular in 23 eyes (41%), anterior cortical, posterior cortical and posterior capsular cataract in one eye (1.7%), anterior cortical and nuclear cataract in one eye (1.7%), anterior cortical, nuclear and posterior capsular cataract in five eyes (8.9%), and anterior cortical cataract in seven eyes (12.5%). Abnormal ultrasonographic alterations were observed in the posterior segment in 26 eyes evaluated (46.4%). Vitreal degeneration was detected in 12 eyes (21.4%), images of vitreal exudate or hemorrhage in seven eyes (12.5%), persistence of hyaloid artery in four eyes (7.1%) and lens subluxation in three eyes (5.3%). The results obtained reiterate the importance of ultrasonography in canine patients presented for cataract surgery given that alterations of the posterior segment are difficult to identify in a clinical examination when the lens is opacified.

Canine distemper virus detection in asymptomatic and non vaccinated dogs

A quantitative real time polymerase chain reaction (PCR) revealed canine distemper virus presence in peripheral blood samples from asymptomatic and non vaccinated dogs. Samples from eleven domestic dogs with no signs of canine distemper and not vaccinated at the month of collection were used. Canine distemper virus vaccine samples in VERO cells were used as positive controls. RNA was isolated with Trizol®, and treated with a TURBO DNA-free kit. Primers were designed for canine distemper virus nucleocapsid protein coding region fragment amplification (84 bp). Canine b-actin (93 bp) was utilized as the endogenous control for normalization. Quantitative results of real time PCR generated by ABI Prism 7000 SDS Software showed that 54.5% of dogs with asymptomatic canine distemper were positive for canine distemper virus. Dissociation curves confirmed the specificity of the real time PCR fragments. This technique could detect even a few copies of viral RNA and identificate subclinically infected dogs providing accurate diagnosis of this disease at an early stage.

Risk factors and presence of antibodies to Toxoplasma gondii in dogs from the coast of São Paulo State, Brazil

Toxoplasmosis is caused by the obligate intracellular protozoan parasite Toxoplasma gondii and affects warm-blooded vertebrates, including pets and man. Dogs are epidemio-logically important since they act as sentinels for the infection in humans. The present study aimed to determine the presence of antibodies to T. gondii in 205 serum samples from dogs in Ubatuba, Sao Paulo state, Brazil, through indirect immunofluorescence reaction (IFAT), as well as the risk factors related to toxoplasmosis in the animals such as breed, age, sex, access to outdoors, homemade food ingestion, access to untreated water, and contact with rodents. Toxoplasmosis-positive samples accounted for 52/205 (25.4%), with titers ranging from 16 to 256. The serological results presented significant association (P<0.05) with homemade food ingestion (45/118; 38.1%; CI95% 29.9%-47.2%) (OR=7.0; CI95% 3.0-16.6), and with access to outdoors where those that do not have access to the street were prevalent (37/121; 30.6%; CI95% 23.1%-39.3%) (OR=0.5; CI95% 0.2-1.0). These results show that toxoplasmosis in this region is related to problems of sanitary education, mainly concerning the appropriate cooking of foods, since most positive animals did not show significant association with the presence of rodents or untreated water consumption but showed, instead association with ingestion of homemade food. Thus, toxoplasmosis is a public health problem in the studied region, and sanitary measures are needed to control the infection due to the strict relationship between man and dog and the presented risk factors