Parâmetros fisiológicos do desempenho de cavalos de alta performance hidratados voluntariamente com água ou solução isotônica contendo carboidrato

During eight weeks, in summer, four endurance trained high performance horses were worked in resistence exercise, recieving two different types of hydratatio, water or an isotonic solution containing carbohydrates, with the objective to compare their performance physiological parameters. Only the RT (rectal temperature), HR (heart rate), RR (respiratory rate), weight, total protein, glucose, the electrolytes K, Ca and the muscular enzyme CK presented distance effect. The others parameters evaluated, there weren't any identified effects of treatment and of the interaction between distance and treatments, with a significancy level of 5%, and it was concluded that the isotonic solution containing carbohydrate didn't have any significant influence on the animal's performance when compared to water.

Aspirado traqueal de cavalos clinicamente sadios da raça quarto de milha após prova de três tambores

The aim of the present study was to evaluate through endoscopy the tracheal aspiration cytology in twenty seven Quarter Horses from Curitiba and surroundings, following the Three Barrel Competittion. Upper respiratory tract secretion was obtained by tracheal aspiration using a polyethylene catheter introduced through the endoscopic fiberoptic working channel, at the level of tracheal bifurcation. Cytologic slides were prepared by smear and stained by diff-quick technique and the differential was performed in 500 cells counting by 1,000X optic microscopy. None of the horses presented abnormality, including epixtasis, at the clinical examination. However, hemosiderophages were detected at cytology in three animals, suggesting that some may be suffering of subclinical pulmonary hemorrhage. Differential cell counting of tracheal aspiration results were, in average: 44.09 ± 35.68% of epithelial cells; 1.10 ± 2.18% of Globet cells; 23.10 ± 35.93% of neutrophils; 0.13 ± 0.37% of lymphocytes; 0.91 ± 2.81% of eosinophils; 30.57 ± 23.62% of macrophages and 0.13 + 0.93% of hemosiderophages. In conclusion, based in the present study, the evaluation of cellular populations with the tracheal aspiration may offer important additional information to the clinician, particularly about the inflammatory processes of lower respiratory tract and pulmonary bleeding.

Correlações entre deslocamento e conformação em eqüinos Mangalarga

The aim of this study was estimate genetic, environmental and phenotypic correlations between movement and conformation traits in Mangalarga horses, in Brazil. The data were provided by Brazilian Association of Mangalarga Horses Breeders, comprised 9865 observations for movement and conformation traits. The data were organized by SAS, and the (co)variance components were estimated by the program MTGSAM. The heritabilities estimates varied from 0.22 (shoulder) to 0.29 (limbs), and the genetic correlations ranged from 0.51 (movement and neck) to 0.31 (movement and limbs).

Estudio cuantitativo de los tiempos en las carreras de purasangre en pistas de tierra y césped en Brasil

This study was conducted to estimate the genetic parameters for race times on turf and dirt tracks of Thoroughbred race horses. Data used were recorded by the Turftotal Ltd. for 343,419 racing performance of 26,713 animals, from January 1992 to January 2003. The model used in analysis included random animal and permanent environmental effects, and age, post position at start, sex and race as fixed effects. The variance and covariance components and the breeding value were estimated using the MTGSAM software. Heritability estimates were 0.29 for time on dirt track and 0.25 for time on turf track, indicating a moderate association between the animals' breeding values and their phenotypic values. Although genetic and environmental variances were smaller in turf tracks, their repeatability was equal to that of dirt (0.56), in terms of the highest estimated phenotypic variance for the latter type of track. The genetic correlation between times on different tracks was high (0.70). Considering the mean breeding value of the progeny of 465 stallions with 10 or more offspring, Spearman's correlation was 0.80, indicating that most Thoroughbred stallions produce offspring suited to both dirt and turf racing tracks.

Comparação dos efeitos da romifidina e de uma emulsão de amitraz na sedação e na atividade locomotora espontânea de eqüinos

Amitraz (AM) and romifidine (RMF), two alpha-2 adrenoceptor agonists, produce sedative effect and decrease spontaneous locomotor activity (SLA) of horses. The behavioral effects and sedation after intravenous injection of RMF (0.06mg/kg) or AM 0.1mg/kg (AM 0.1) or AM 0.4mg/kg (AM 0.4) were compared in horses. RMF caused head ptosis (HP) until 45 min. The lower AM dose induced HP from 45 to 60 minutes and from 120 to 150 minutes, and the higher dose induced HP until 180 minutes. Data concerning changes in SLA were not conclusive. RMF or AM 0.4 caused a greater sedation than AM 0.1 until 20 min. After 20 minutes, the sedation caused by AM 0.4 was greater than that of RMF or AM 0.1. Romifidine caused consistent sedation until 45 minutes. The amitraz emulsion produced a dosedependent sedation until 180 minutes. Comparing to romifidine, the emulsion of amitraz induced a more substantial sedation. At dosages and dilution applied, amitraz is an effective sedative for horses.

Aplicação da espirometria durante teste padrão de exercício progressivo em esteira para avaliação da troca gasosa respiratória de equinos da raça árabe

The current study evaluated equine gas exchange responses through spirometry, by measuring oxygen uptake (VO2), carbon dioxide production (VCO2), respiratory exchange ratio (R) and maximum oxygen uptake (VO2max) of Arabian horses during a standard incremental exercise test performed on a high-speed treadmill. Six clinically healthy Arabian horses were submitted to a standard incremental exercise test, performed on a high-speed treadmill at a 6% slope, and initial speed of 1,8 m.s-1 for 5 minutes, then 4,0 m.s-1 for 3 minutes, 6,0 m.s-1 for 2 minutes and 8,0 m.s-1, 9,0 m.s-1, 10,0 m.s-1 and 11,0 m.s-1 for one minute for each of these speed. The end of the exercise test was defined as the point in which the horse was no longer able to keep pace with the treadmill. Gas exchange was measured through respiratory analyses horse mask on the last 10 seconds at the end of each speed transition and at 1, 2 and 3 minutes after the end of the exercise, defined as experiment moments. During exercise, it was noticed an increase on both VO2 and VCO2 with linear relationship between exercise and speed. Arabian horses VO2max was 114,9 mL.kg-1.min-1. The respiratory exchange ratio increased over 1,0 by the speed of 9,0 m.s-1, indicating the preponderance of the anaerobic metabolism, and remains at a high level on the post-exercise period.

Comportamento exploratório de potros e éguas mediante a introdução de novos objetos em seu meio

Exploratory behavior is done by animals to increase their interaction to the environment after be stimulated by curiosity, when animal feels that is in a secured place. The objective of this study was to evaluate exploratory behavior of foals front of introduction of new objects in their environment. Four foals and mares were observed in seven day sections of 60 minutes each one, always with a new object. No differences were verified about frequencies of looking, going to or touching into foals and mares. Total time of touching was 45,6 minutes, divided in 64 touches, mainly in first 20 minutes of each observation. However there is no statistical difference into solitary or impaired approaches and in impaired approaches there is no differences into foals or mares initiatives, foals done more solitary approaches than mares. Four animals touched the objects in first place, suggesting predisposition to this position based in individual differences. So, we concluded that new objects can stimulate similarly foals and mares to exhibit exploratory behavior, but foals show more manipulation activity, suggesting that are more curious than mares and predisposition to touch objects first depends of individual differences.

Resposta plasmática de glicose e insulina em eqüinos alimentados com diferentes fontes de amido

This study was aimed to measure the plasmatic response of glucose and insulin of horses fed diets containing different starch sources, like corn, oat, sorghum and a mix of corn and oat in equal parts. Four standarbred gelding 36 month old an weighing average of 350 kg were used in a Latin Square 4 x 4 (four animals, four treatments and four period) trial design. No statistical differences were observed in plasmatic glucose levels either before or after ingestion between treatments. Maximum plasmatic level of glucose was observed in all diets two and a half hours post ingestion. Insulin plasmatic level was significantly lower before ingestion in horses treated with the mixed corn and oat diet, when compared with the other treatments. In the other hand, the insulin plasmatic level in horses fed corn-formulated diet was statistically higher than the others treatments at three hours and a half after ingestion. Diets containing different sources of starch had no effect in time neither quantity of glucose absorbed in small intestine. Variation observed in insulin plasmatic levels indicate that a proper feeding can have a regulatory effect of this hormone, avoiding undesirable's behaviors.

Cellular localization of androgen synthesis in equine granulosa-theca cell tumors: Immunohistochemical expression of 17α-hydroxylase/17,20-lyase cytochrome P450

Elevated blood testosterone concentrations, often accompanied by male-typical behaviors, is a common signalment of mares with granulosa-theca cell tumors (GCTCs), but no definitive information exists regarding the cellular differentiation of tumors associated with androgen secretion. This study was conducted to localize and thereby define the cellular expression of 17α-hydroxylase/17,20-lyase cytochrome P450 (P450c17), the enzyme most directly responsible for androgen synthesis, in 30 GTCTs and control tissues (gonads and adrenal glands) using immuno-histochemistry (IHC). Immuno-reactivity for P450c17 was evident in approximately half of 30 specimens examined, was most consistent in the interstitial cells surrounding existing or developing cysts, and was less intense in cells within cysts in the smaller proportion of specimens where this was observed. In control tissues, the expression of P450c17 was localized primarily in theca interna of normal ovarian follicles, in theca-lutein cells of some corpora lutea, but not in granulosa-lutein cells. Testicular interstitial cells and islands of adreno-cortical cells located in the adrenal medulla of the adrenal cortex further established the specificity of the antisera used. These data provided the first substantive evidence that polyhedral cells identified previously in GTCTs by histopathology have the potential to synthesize and secrete androgens, similar to theca interna and theca lutein cells in normal equine ovaries. © 2010 Elsevier Inc.

Efeitos da fenilbutazona na cicatrização de feridas cutâneas experimentais em equinos

The purpose of this study was to investigate phenylbutazone effects on second intention wound healing, and to compare the healing process between the thoracic and lumbar areas. Ten horses were submitted to circular full-thickness wound produced on both sides of the thoracic and lumbar areas. Animals were gathered into two experimental groups, one receiving daily IV injections of phenylbutazone (4,4mg/kg) and the other (control group) distillated water for five days. All wounds were daily treated with local Dakin's solution. The wound contraction rates were determined by serial measurements each 72 hours. At the 6th and 15th post surgical days, biopsies were performed for histological analysis. Thoracic and lumbar wound contraction was decreased in the phenylbutazone group. The time to complete healing was significantly greater in phenylbutazone group (49 days) than in control group (37 days). There was no significant difference between thoracic and lumbar area in the same group. Gross and histopathology analysis showed the inhibitory effect of phenylbutazone on the second-intention wound healing when compared to the control group.

Avaliação radiográfica da aplicação do polímero de mamona em falhas ósseas induzidas em equinos

It was evaluated the radiographs alteration of the castor oil bean polymer applied for the filing of induced bone fault in horses. Five animals were evaluated, subjected to a local anesthesia and sedation, proceeding to a surgical induction of a hole in the radio bone, in both members with three centimeters depth perforations. It was used a drill of eight millimeters of diameter. The right member served as a control, without filling induced holes. The holes in left radio were filled with the commercial polymer derived from the castor oil bean. We evaluated the localized swelling and radiological aspects as: the establishment of scores for bone filling, sclerosis and a morphometric analysis of the sclerosis area, in 15, 45, 90 and 180 days of lesion evolution. There was more swelling in local members whose injuries were filled with polymer from castor oil bean. By comparison, the radiographic examination showed better bone filling in the gaps of members control. We concluded that the completion of castor oil bean polymer in bone holes induced in radio of horses, delayed the bone healing, in the radiographic evaluation.

Description and genetic analysis of three sets of monozygotic twins resulting from transfers of single embryos to recipient mares

Case Description-3 sets of monozygotic twins resulting from transfers of single embryos to recipient mares were examined. Clinical Findings-In all 3 recipient mares with twin pregnancies, only 1 embryonic vesicle was detected before day 25 of gestation. In 1 recipient mare, 2 apparent adjacent vesicles, each containing an embryo with a heartbeat, were visualized on ultrasonographic examination on day 37 of gestation. The other 2 recipient mares underwent ultrasonographic examination on day 30 of gestation, at which time only 1 vesicle and embryo was identified. In these latter 2 recipient mares, however, a thorough ultrasonographic examination for a second conceptus on day 30 had not been performed, as only 1 embryo had been transferred and visualized on early ultrasonographic examination. Treatment and Outcome-All twin pregnancies resulted in death of both fetuses. Genetic analysis confirmed that each set of monozygotic twins originated from the transferred embryo. Clinical Relevance-Monozygotic twin pregnancy may occur after embryo transfer; thus recipient mares should be examined thoroughly for multiple conceptuses, especially between 25 and 30 days of gestation. At this time, the allantoides of monozygotic twins should be visible ultrasonographically and effective management may still be possible.

Protocolo de exame físico para a coluna toracolombar de equinos

Thoracolumbar injuries represent a challenge to the veterinarian that seeks to eliminate the pain, reinstitute the athletic use of the horse and minimize economic losses. The percentage of lost training days due to orthopedic conditions in race horses is of 72.1% and within those conditions is back pain, whicht represents from 4.35% to 20% of the lameness cases. The present study searched to establish a protocol based on score points for the thoracolumbar physical exam, by which it is able to determine the possible affected areas and the seriousness of the injuries. Along with the physical exam, it was performed an ultrasonographic exam of the thoracolumbar region to characterize and classify the injuries found, as to accompany its evolution after treatment. It was observed a clear reduction in the physical exam score sum in all animals between the exam days being that the exam of most of the animals presented a zero score at 60 days after the treatment. Relating the evolution of the clinical exam with the ultrasonography image tests, there was a positive association between the reduction score in the severity scale and the evolution of the ultrasonographic image of the evaluated structures. Thus, it can be concluded that gradation of the physical exam showed to be efficient and allowed the monitoring of the clinical evolution, as the answer of the injuries to the suggested treatment. Besides that, the results showed that 60 days is the ideal time for the first reevaluation of the animal after the treatment.

First defection of the equine herpesvirus 1 neuropathogenic variant in Brazil

This report describes the first detection of an equine herpesvirus 1 (EHV-1) neuropathogenic variant (G 2254/D 752) in Brazil from a case of fatal equine herpesvirus myeloencephalopathy (EHM) in a mare. The results of nucleotide sequencing of the EHV-1 ORF30 gene showed that two other Brazilian EHV-1 isolates from EHM cases are representatives of the non-neuropathogenic variant (A 2254/N 752), suggesting that other unidentified factors are probably also involved in the neuropathogenicity of EHV-1 in horses. These findings will contribute to the epidemiological knowledge of EHV-1 infection in Brazil.

Detecção de anticorpos anti-Toxoplasma gondii em cavalos carroceiros da região metropolitana de Curitiba, Paraná, Brasil

Toxoplasma gondii, the agent for toxoplasmosis, has worldwide distribution. Horses normally play a secondary role in its life cycle, but movement around urban areas, feeding on grass and the increasing use of carthorses for gathering recyclable material in some urban areas of Brazil may increase their exposure to T. gondii infection. The aim of the present study was to investigate the frequency of anti-T. gondii antibodies in carthorses in the metropolitan region of Curitiba, PR. IgG antibodies against T. gondii were detected using the indirect fluorescence antibody test (IFAT) (titers ≥ 64). Seventeen (17.0%) of the 100 horses sampled were seropositive. There were no statistical differences in relation to sex (p = 0.28) or age (p = 0.15). Our findings suggest that carthorses are exposed to T. gondii infections and that no associations with age or sex exist.