Morphine with or without Acepromazine in Horses: A Kinematic Evaluation.

The objective was to demonstrate walking locomotor pattern alterations after co-administration of acepromazine and morphine in horses. Six mature horses receiving four different treatments were used. Treatments consisted of a single dose of saline solution, 0.2 mg/kg bwt of morphine hydrochloride, 0.02 mg/kg bwt of acepromazine maleate, and a combination of 0.2 mg/kg bwt of morphine hydrochloride with 0.02 mg/kg bwt of acepromazine maleate. A three-dimensional accelerometric device was used to collect data. Walking tests were performed 10 min prior to injection, and then at 5, 10, 15, and 20 min after the injection, and then every 10 min for 3 h. Eight variables were calculated including stride kinematic, coordination, and energetic parameters; moreover ground-to-lip distance (GLD), as a tranquilization parameter, was also measured. A significant interaction was observed in all the variables studied but regularity, mediolateral power, the propulsive part of the power, and the GLD. An evident counteraction of the effects caused by both, opioids and phenothiazines, in the gait pattern was observed. The co-administration of acepromazine and morphine could allow a safe opiate administration while minimizing the possible central nervous system (CNS) excitation and reducing potential locomotor adverse effects.

Accelerometric Evaluation of the Locomotor Pattern After Administration of Morphine in Conscious Healthy Horses.

The objective of the present study was to compare, using accelerometry, the gait changes produced after administration of a dose of 0.2 mg/kg of morphine at the walk in healthy horses. Six mature horses were used, and all animals received two different treatments with, at least, two weeks interval in between. Treatments administered consisted of a single dose of 10 ml of saline solution or a total of 0.2 mg/kg of morphine diluted in 10 ml of saline solution. A three-dimensional accelerometric device was used to collect data continuously while horses were walking. The walking test was performed 10 min prior to injection, and then at 5, 10, 15 and 20 min after injection and then every 10 min for 3 h. Eight variables were calculated including stride kinematic, coordination and energetic parameters. Additionally, the force of acceleration and three components of the power were calculated. Significant interaction was only observed for stride length, propulsion power and the propulsive part of the total power with a reduction in values after morphine administration. Compared to baseline values, stride length values were significantly reduced for 80 min and again 110 min after injection of the opioid and at 5, 15, 20, 30 and 40 min in the case of propulsion power values. For the propulsion component of power, these differences were observed for 20 min when compared to baseline values. The administration of 0.2 mg/kg of morphine to conscious healthy horses produces limited effects on the gait pattern of horses and the effects on locomotor activity are minimal at this dose, not being an important concern for the administration of analgesia in a clinical setting.

Prevalence and characteristics of osteochondrosis in 309 Spanish Purebred horses.

Articular osteochondrosis (OC) is commonly reported in horses but there are no reports of its prevalence in the Spanish Purebred (SP). The objective of this study was to assess the prevalence and characteristics of OC of the tarsocrural, dorsal metacarpo-metatarsophalangeal and femoropatellar joints in the SP in a retrospective study. The data were obtained from the radiographs of 309 SP horses and the prevalence and characteristics of lesions were calculated. Osteochondral lesions at predilected sites were diagnosed in 48.8% of the horses. It was more common to find the presence of fragments (28.8%) than flattening of the subchondral bone contour (20.1%). The percentage with abnormal articular margins was 1.3% for the femoropatellar joint, 33.3% for the tarsocrural and 25% for the dorsal fetlock region, where flattening was more common than the presence of fragments; in the tarsus and stifle, fragments were more common. The severity of the disease in the dorsal fetlock area was higher in hindlimbs than in forelimbs. Femoropatellar lesions were rare. Osteochondrosis is a common disease in the SP and this study provides information about the prevalence of osteochondrosis lesions in the breed and the interrelationships between the joints.

The use of low doses of acepromazine as an aid for lameness diagnosis in horses: An accelerometric evaluation.

OBJECTIVES: The aim of the present study was to quantify by accelerometry the trotting pattern of adult horses sedated with two different doses of acepromazine, in order to assess the use of this drug in equine lameness evaluations. METHODS: Seven mature horses were used and three treatments were administered to each horse: saline solution, acepromazine (0.01 mg/kg), and acepromazine (0.02 mg/kg). The portable gait analyzer used consisted of three orthogonal accelerometers that measure accelerations along the dorsoventral, longitudinal, and lateral axes. Baseline values were obtained and after treatment, accelerometric recordings were repeated every five minutes during the first 20 minutes after the injection and then every 10 minutes thereafter for two hours. Ground-to-lip distance was also measured. RESULTS: Administration of acepromazine decreased some of the variables investigated and differences between doses were observed. Speed, stride frequency, and stride length were significantly reduced following treatments. For coordination parameters, no significant differences among values were observed. Energetic variables suffered only weak reductions whereas ground-to-lip distance values were significantly decreased up to 120 minutes after treatment. CLINICAL SIGNIFICANCE: Acepromazine produces significant alterations in the gait pattern with differences between doses, but it does not affect coordination variables in normal unexcited horses, and at a dose of 0.01 mg/kg may be the tranquilizer of choice for evaluating lameness in this setting.

Evaluation of traction stirrup distraction technique to increase the joint space of the shoulder joint in the dog: A cadaveric study.

The objective of this study was to evaluate technical feasibility and efficacy of a joint distraction technique by traction stirrup to facilitate shoulder arthroscopy and assess potential soft tissue damage. Twenty shoulders were evaluated radiographically before distraction. Distraction was applied with loads from 40 N up to 200 N, in 40 N increments, and the joint space was recorded at each step by radiographic images. The effects of joint flexion and intra-articular air injection at maximum load were evaluated. Radiographic evaluation was performed after distraction to evaluate ensuing joint laxity. Joint distraction by traction stirrup technique produces a significant increase in the joint space; an increase in joint laxity could not be inferred by standard and stress radiographs. However, further clinical studies are required to evaluate potential neurovascular complications. A wider joint space may be useful to facilitate arthroscopy, reducing the likelihood for iatrogenic damage to intra-articular structures.

An accelerometric measure of the gait pattern in horses after the administration of sublingual detomidine.

The locomotor pattern alterations produced after the administration of a sublingual detomidine gel was measured by an accelerometric method in horses. Using a randomized two-way crossover design, all animals (n = 6) randomly received either detomidine gel or a placebo administered sublingually. A triaxial accelerometric device was used for gait assessment 15 minutes before (baseline) and every 10 minutes after each treatment for a period of 180 minutes. Eight different parameters were calculated, including speed, stride frequency, stride length, regularity, dorsoventral, propulsion, mediolateral, and total power. Force of acceleration and the three components of power were also calculated. Significant statistical differences were observed between groups in all the parameters but stride length. The majority of significant changes started between 30 and 70 minutes after drug administration and lasted for 160 minutes. This route of administration is definitely useful in horses in which a prolonged sedation is required, with stability being a major concern.

Accelerometric comparison of the locomotor pattern of horses sedated with xylazine hydrochloride, detomidine hydrochloride, or romifidine hydrochloride.

OBJECTIVE: To evaluate the duration of effects on movement patterns of horses after sedation with equipotent doses of xylazine hydrochloride, detomidine hydrochloride, or romifidine hydrochloride and determine whether accelerometry can be used to quantify differences among drug treatments. ANIMALS: 6 healthy horses. PROCEDURES: Each horse was injected IV with saline (0.9% NaCl) solution (10 mL), xylazine diluted in saline solution (0.5 mg/kg), detomidine diluted in saline solution (0.01 mg/kg), or romifidine diluted in saline solution (0.04 mg/kg) in random order. A triaxial accelerometric device was used for gait assessment 15 minutes before and 5, 15, 30, 45, 60, 75, 90, 105, and 120 minutes after each treatment. Eight variables were calculated, including speed, stride frequency, stride length, regularity, dorsoventral power, propulsive power, mediolateral power, and total power; the force of acceleration and 3 components of power were then calculated. RESULTS: Significant differences were evident in stride frequency and regularity between treatments with saline solution and each α2-adrenoceptor agonist drug; in speed, dorsoventral power, propulsive power, total power, and force values between treatments with saline solution and detomidine or romifidine; and in mediolateral power between treatments with saline solution and detomidine. Stride length did not differ among treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Accelerometric evaluation of horses administered α2-adrenoceptor agonist drugs revealed more prolonged sedative effects of romifidine, compared with effects of xylazine or detomidine. Accelerometry could be useful in assessing the effects of other sedatives and analgesics. Accelerometric data may be helpful in drug selection for situations in which a horse's balance and coordination are important.

Effects of single hyperinflation using a sustained high pressure manoeuvre during inhalation anaesthesia in horses.

The effect of a single hyperinflation using a sustained high-pressure manoeuvre (SHPM) during inhalation anaesthesia was evaluated in horses. Twenty-eight client-owned male horses were recruited; 14 were operated on in dorsal recumbency and 14 in lateral recumbency. For each category, horses were randomly allocated to either the 'breathing spontaneously' or 'mechanically ventilated' group. After 30 min of anaesthesia, baseline cardiorespiratory parameters were collected and a SHPM of 50 cmH2O during 50s was undertaken. In the group of horses breathing spontaneously and positioned in dorsal recumbency, venous admixture developed significantly more than in other groups and a single SHPM only partially and transiently improved arterial oxygenation. No benefit of the respiratory manoeuvre was observed in the other groups.

Gait analysis using 3D accelerometry in horses sedated with xylazine.

The aim of the present study was to verify the efficacy and sensitivity of an accelerometric device in detecting and quantifying the degree of movement alteration produced in horses sedated with xylazine. Horses (n=6) were randomly administered either xylazine or a control by intravenous injection, with at least 1 week between each treatment. A triaxial accelerometric device was used for the accelerometric gait assessment 15 min before (baseline) and 5, 15, 30, 45, 60, 75, 90, 105 and 120 min after each treatment. Eight different accelerometric parameters were calculated, including speed, stride frequency, stride length, regularity, dorsoventral power, propulsion power, mediolateral power and total power, with the force of acceleration and the dorsoventral, mediolateral and craniocaudal (propulsive) parts of the power then calculated. Administration of xylazine decreased many of the parameters investigated, with significant differences for speed, stride frequency, dorsoventral power, propulsion power and total power at 5, 15, 30 and 45 min after injection. There were no significant differences in stride length values at any time point. Decreases in regularity values were evident with significant differences at every time point from 5 to 120 min following xylazine injection. Force values were also significantly reduced from 5 to 30 min after treatment and a redistribution of the total power was observed 5 min after injection as the mediolateral power increased significantly, while the dorsoventral power decreased. Accelerometry offers a practical, accurate, easy to use, portable and low cost method of objectively monitoring gait abnormalities at the walk in horses after sedation with xylazine.

Evaluation of the local analgesic effect of ketamine in the palmar digital nerve block at the base of the proximal sesamoid (abaxial sesamoid block) in horses.

OBJECTIVE: To evaluate the local analgesic effect of ketamine in a palmar digital nerve block at the base of the proximal sesamoid (abaxial sesamoid block) in horses. ANIMALS: 36 mature healthy Andalusian horses. PROCEDURE: Horses were randomly assigned to 4 groups of 9 horses each and received an abaxial sesamoid block in a randomly chosen forelimb with 1 of the following: saline (0.9% NaCl) solution, 1% ketamine solution, 2% ketamine solution, or 3% ketamine solution. To determine analgesia, the radiant heat lamp-hoof withdrawal model was used as a noxious thermal stimulus. Before each nerve block, baseline hoof withdrawal reflex latency (HWRL, time between lamp illumination and withdrawal of the hoof) was determined; after the nerve block, local analgesic effects were determined by measuring HWRL at 2 and 5 minutes after injection and then every 5 minutes for a total period of 1 hour. RESULTS: Significant differences in HWRL were found between baseline values and values at 2 to 15 minutes following a nerve block with ketamine. Significant differences were found between HWRL values at every time point from 2 to 10 minutes following a nerve block with saline solution, compared with 1 or 2% ketamine solution. Similarly, significant differences were found between HWRL values at every time point from 2 to 15 minutes following a nerve block with saline solution, compared with 3% ketamine solution. CONCLUSIONS AND CLINICAL RELEVANCE: Abaxial sesamoid block with ketamine ensures adequate analgesia in horses with an onset of action of 2 minutes and a maximal duration of action of 15 minutes.

[Endodontics in horses. An experimental study]. / Endodoncia en equidos. Estudio experimental.

A total of 44 experimental endodontic treatments were performed in incisors of eight horses of different ages. Four different endodontic pastes were used: Cloropercha, AH26 De Trey, Eugenol-Endometasone, and Universal N2. Gutta-percha points were also included in the last two treatments. Access to the pulp cavity of incisors was gained through their vestibular and occlusal faces. Holes drilled in vestibular faces were sealed with composite and those drilled in occlusal faces were sealed with Amalgama. Animals were observed during eighteen months at least after endodontics. Radiographic controls were done just after surgery and before slaughtering. Treated incisors and alveoli were studied histopathologically. During the experiment all animals were in good condition. They ate apparently without trouble, and neither clinical nor radiological signs were present.

[Comparative study of two different types of dental implants in dogs. Experimental study]. / Estudio comparativo de dos tipos diferentes de implantes dentarios en Perros. Estudio experimental.

Mandibular incisors were taken out in 13 adult dogs. Twenty days after the extraction, two implants either of titanium or hydroxylapatite were placed in a second operation. The clinical, pathological and radiological results suggest that metallic implants produce fibrous tissue around the implant. In most cases, fibrous tissue does not ossify and this facilitates the formation of a malunion and the mobilization of the implant. However, the results with hydroxylapatite implants appear to be satisfactory due to the formation of an osseous tissue mandibular bone. This tissue prevents the mobilization of the implant allowing support to a dental prostheses.

Comparison of two orthodontical techniques for the correction of lingual deviation of upper incisors in the dog.

Two different orthodontic treatments were applied to dogs exhibiting lingual deviation of maxillary incisors. Two dogs were treated by means of an orthodontic device consisting of an acrylic plate fitted with a counteracting spring. The results were disappointing. These animals and two other dogs were treated with Schwarz's orthodontic device. After 3 to 4 months of treatment, lingual malposition of incisors was successfully corrected. Orthodontic therapy induced problems were unimportant and with collaborating owners could be easily overcome.