Comparison of magnetic resonance imaging and myelography in 18 Doberman pinscher dogs with cervical spondylomyelopathy.

Eighteen Doberman pinscher dogs with clinical signs of cervical spondylomyelopathy (wobbler syndrome) underwent cervical myelography and magnetic resonance (MR) imaging. Cervical myelography was performed using iohexol, followed by lateral and ventrodorsal radiographs. Traction myelography was performed using a cervical harness exerting 9 kg of linear traction.

Correlation of motor evoked potentials with magnetic resonance imaging and neurologic findings in Doberman Pinschers with and without signs of cervical spondylomyelopathy.

Objective: To establish the reference ranges for motor evoked potential (MEP) latency and amplitude in clinically normal Doberman Pinschers, compare the MEPs of Doberman Pinschers with and without clinical signs of cervical spondylomyelopathy (CSM; wobbler syndrome), and determine whether MEP data correlate with neurologic or magnetic resonance imaging (MRI) findings.

Animals: 16 clinically normal and 16 CSM-affected Doberman Pinschers.

Procedures: Dogs were classified according to their neurologic deficits.

Morphologic and morphometric magnetic resonance imaging features of Doberman Pinschers with and without clinical signs of cervical spondylomyelopathy.

Objective: To compare morphologic and morphometric features of the cervical vertebral column and spinal cord of Doberman Pinschers with and without clinical signs of cervical spondylomyelopathy (CSM; wobbler syndrome) detected via magnetic resonance imaging (MRI).

Animals: 16 clinically normal and 16 CSM-affected Doberman Pinschers.

Procedures: For each dog, MRI of the cervical vertebral column (in neutral and traction positions) was performed.

Neurogenesis of oxytocin-containing neurons in the paraventricular nucleus (PVN) of the female pig in 3 reproductive states: puberty gilts, adult gilts and lactating sows.

Evidence suggests that neurogenesis occurs in the adult hypothalamus, including centers containing oxytocin and vasopressin producing neurons. The present study was undertaken to look at one of these centers, the paraventricular nucleus (PVN), to describe its morphology, confirm the presence of neurogenesis and examine the effect of reproductive status on the incidence of neurogenesis. Serial sections of the paraffin-embedded hypothalamus were made from five puberty gilts, four adult gilts and four lactating sows.

Schistosomus reflexus syndrome: a heritable defect in ruminants.

Schistosomus reflexus (SR) is a rare and fatal congenital disorder. Primarily observed in ruminants, its defining features include spinal inversion, exposure of the abdominal viscera because of a fissure of the ventral abdominal wall, limb ankylosis, positioning of the limbs adjacent to the skull and, lung and diaphragm hypoplasia. Variable components of SR include scoliosis, cleft sternum, exposure of thoracic viscera, and abnormalities of the digestive and urogenital systems.

A proposed mechanism for intermediate atresia ani (AA), based on a porcine case of AA and hypospadias.

Background: Atresia Ani (AA) is one of the most common malformations of the lower gastrointestinal tract. It occurs in 1 in 1500 to 1 in 5000 human births. These patients suffer physically and psychologically from this disorder, and thus there is a research interest in the condition.

The use of proliferating cell nuclear antigen immunohistochemistry with a unique functional marker to detect postnatal neurogenesis in paraffin-embedded sections of the mature pig brain.

Until recently, evidence supporting postnatal neurogenesis was controversial. Much of the debate has centered on the identification of the dividing cells as neurons versus glia. Because neurogenesis has become a well-documented phenomenon, there is a need for reliable protocols to identify recently divided neurons in a wide range of situations.

Postnatal neurogenesis in the vasopressin and oxytocin-containing nucleus of the pig hypothalamus.

The vasopressin and oxytocin-containing nucleus (VON) of the pig hypothalamus demonstrates dramatic postnatal growth in nucleus size, both volume and neuron number, during puberty, and continues to increase in size in the adult sexually mature female pig throughout its reproductive prime. This study was designed to show that postnatal neurogenesis is responsible for the VON growth that occurs between adolescence and maturity. Recently divided neurosecretory cells of the hypothalamus were identified in adolescent and mature non-lactating female pigs using a sequential immunohistochemistry double-labeling technique with monoclonal mouse antibodies to detect vasopressin and proliferating cell nuclear antigen (PCNA), a protein associated with the S phase of the cell cycle.

Correlation between severity of clinical signs and motor evoked potentials after transcranial magnetic stimulation in large-breed dogs with cervical spinal cord disease.

Objective: To evaluate use of transcranial magnetic motor evoked potentials for assessment of the functional integrity of the cervical spinal cord in large-breed dogs with cervical spinal cord disease.

Design: Randomized, controlled, masked study.

Animals: 10 healthy large-breed control dogs and 25 large-breed dogs with cervical spinal cord diseases.

Single ventricle, total transposition, and hypoplastic aorta in a calf.

A purebred Ayrshire calf was born with multiple congenital cardiac defects. The major defects included absence of an interventricular septum (i.e.

Abdominal situs inversus in a Holstein calf.

Situs inversus is a rare congenital anomaly wherein the normal, left-right organ location is inverted. The anatomical inversion (heterotaxy) is usually detected in routine radiography or other medical interventions. A 5-month-old Holstein heifer calf was identified as a suspected situs inversus totalis during abdominal surgery.

Functional MRI activity in the thalamus and occipital cortex of anesthetized dogs induced by monocular and binocular stimulation.

The neuroanatomy of the mammalian visual system has received considerable attention through electrophysiological study of cats and non-human primates, and through neuroimaging of humans. Canine neuroanatomy, however, has received much less attention, limiting our understanding of canine vision and visual pathways. As an early step in applying blood oxygenation level dependant (BOLD) functional magnetic resonance imaging (fMRI) for veterinary use, we compared visual activity in the thalamus and occipital cortex of anesthetized dogs presented with binocular and monocular visual stimuli.

Anatomy of the lumbosacral spinal cord in rabbits.

This study provides an accurate, anatomical description of the rabbit's lumbosacral spinal cord. Following humane euthanasia, 64 rabbits were radiographed and dissected. The number of thoracic (T) and lumbar (L) vertebrae was 12T/7L in 43.

Parapagus conjoined twin Holstein calf.

Background: Conjoined twins with a doubling of all cranial structures, having two vertebral columns along their entire body length yet with a single pelvis, have not been described in the literature. The cause of conjoined twinning is incompletely understood; however, two main theories (fission and fusion) have been proposed and disputed.

Methods: A dicephalus, tetrabrachius (parapagus) conjoined twin Holstein heifer calf was studied.

Agonadal presumptive XX/XY leukochimeric pig.

Background: XX/XY chimeric pigs are uncommon and their reproductive anatomy is variable and unpredictable.

Method: A piglet was identified by its enlarged vulva as a possible intersex. Venous blood was collected at 1.

Conjoined twin piglets with duplicated cranial and caudal axes.

Background: Twins with doubling of the cranial and caudal poles, yet having a single thorax, are rare.

Methods: One set of diprosopus, dipygus porcine conjoined twins was studied.

Results: In addition to the conjoining anomaly, these twins also exhibited ambiguous internal reproductive features.

Prevalence and types of birth defects in Ontario swine determined by mail survey.

Preweaning mortality in piglets constitutes a major loss to the swine industry. Congenital defects account for a small but significant proportion of these losses. To implement appropriate strategies to reduce such losses, it is necessary to identify the specific causes and their relative importance.

Magnetic motor evoked potentials for assessing spinal cord integrity in dogs with intervertebral disc disease.

Magnetically elicited transcranial motor evoked potentials (MEPs) were studied in 37 dogs with type 1 intervertebral disc (IVD) disease. The waveforms were recorded from both cranial tibial muscles before and after surgery. The latencies and amplitudes obtained were compared to those of a control population (n = 14).

Bilateral thalamic glioma: review of eight cases with personality change and mental deterioration.

Purpose: To describe the clinical, radiographic, and neuropathologic features of bilateral thalamic glioma.

Methods: We searched our hospital records (1963 to present) to identify patients diagnosed as having the disease.

Results: Our search revealed eight patients, ranging in age from 8-63 years, with bithalamic tumor diagnosed by angiography, CT, and/or MR.

Ultrastructure of the ventral lateral geniculate nucleus (LGNv) receiving tectal afferents in the cat.

The ultrastructure of the ventral lateral geniculate nucleus (LGNv) associated with the superior colliculus was investigated. In addition to normal synaptic morphology tectal input was examined following unilateral ablation of the superior colliculus at survival times of 2 to 12 days. Eight cats were used (six experimental, two control).

Role of the medial and lateral septum in a variable goal spatial problem solving task.

Rats with lesions to the medial (MS) or lateral septal (LS) nuclei were compared to normal controls (CNT) in the acquisition of a spatial working memory task. In this task, animals were first allowed to explore the unbaited three-table apparatus before being fed on one of the two possible goal tables. Animals were then tested on their ability to return to the table where they just had been fed.

Comparison of androst-16-ene steroid levels determined by a colorimetric assay with boar taint estimated by a trained sensory panel.

A group of 17 intact male pigs and 3 gilts ranging in weight from 96 to 260 kg was selected for sensory evaluation of boar taint in loin chops. Samples were evaluated by 10 trained judges using a 10-cm graphic scale for rating off-aroma, off-flavor, pork flavor, softness, tenderness, juiciness, and residual tissue. In addition, a fry test for taint was conducted by four experienced testers on fat samples from all animals.

Attempts to restore abduction of the paralyzed equine arytenoid cartilage. III. Nerve anastomosis.

The purpose of this project was to attempt restoration of abduction of a recently denervated left dorsal cricoarytenoid muscle in the horse by anastomosing the first cervical nerve to the abductor branch of the left recurrent laryngeal nerve. Ten horses were used in the study. In six horses the left recurrent laryngeal nerve was transected and ligated while the ventral branch of the left first cervical nerve was anastomosed to the abductor branch of the left recurrent laryngeal nerve.

Attempts to restore abduction of the paralyzed equine arytenoid cartilage. II. Nerve implantation (pilot study).

The purpose of this project was to attempt restoration of abduction of a recently experimentally denervated left dorsal cricoarytenoid muscle by implanting a transected nerve-end into the paralyzed muscle. In six ponies the cut end of the second cervical nerve was implanted into a slit made in the left dorsal cricoarytenoid muscle. The nerve end was secured in place with one 5-0 polypropylene suture connecting the epineurium to the epimysium.

Attempts to restore abduction of the paralyzed equine arytenoid cartilage. I. Nerve-muscle pedicle transplants.

The purpose of this project was to adapt a surgical technique from humans and dogs to horses in which a portion of an accessory muscle of respiration and its nerve supply is transplanted to a denervated dorsal cricoarytenoid muscle. Anatomical dissections in seven horses revealed two possible donor nerve-pedicle grafts: the omohyoid and the sternothyrohyoid, both innervated by a branch of the first and second cervical nerves. Histochemical evaluations in two ponies of the dorsal cricoarytenoid, omohyoid and sternothyrohyoid muscles revealed similar proportions of fiber types 1 and 2 in all three muscles.