A COMPARISON OF RADIOGRAPHY, COMPUTED TOMOGRAPHY, AND MAGNETIC RESONANCE IMAGING FOR THE DIAGNOSIS OF PALMAR PROCESS FRACTURES IN FOALS

The relative sensitivity of radiography, computed tomography, and magnetic resonance imaging for detecting palmar process fractures of the distal phalanx in foals was determined and the imaging findings were compared with histomorphologic evaluations of the palmar processes. Compared to radiography, computed tomography and magnetic resonance imaging did not improve the sensitivity for detection of palmar process fractures. Statistical agreement for palmar process fracture diagnosis was excellent among the three imaging modalities. Histomorphologic evaluations were more sensitive for diagnosis of palmar process fracture than any of the imaging modalities. Three-dimensional image reconstructions and volume measurements of distal phalanges and palmar process fracture fragments from computed tomography studies provided more complete anatomical information than radiography. Magnetic resonance imaging confirmed that the deep digital flexor tendon insertion on the distal phalanx is immediately axial to the site where palmar process fractures occur, and differentiated cartilage, bone, and soft tissue structures of the hoof.     

Molecular and genetic comparisons of two serotypes of epizootic hemorrhagic disease of deer virus

The virus-specific double-stranded genome RNA of 2 serotypes of epizootic hemorrhagic disease of deer virus (EHDV) was evaluated by use of coelectrophoresis in polyacrylamide and agarose gel systems. The molecular weights of virion RNA segments were 0.32 to 2.57 X 10(6) for EHDV-1 and 0.33 to 2.54 X 10(6) for EHDV-2. Seven of 10 double-stranded RNA segments of the 2 serotypes had different electrophoretic mobilities in the polyacrylamide-gel electrophoresis system. Although the individual RNA segments of each serotype contained unique RNA sequences determined on the basis of 2-dimensional polyacrylamide-gel electrophoresis analysis of oligonucleotides, the corresponding segments of the 2 serotypes were found to be comparable and at least 1 pair of RNA segment was almost identical. Virus-specific polypeptides for the 2 serotypes were compared by use of gel electrophoresis. Eleven polypeptides were detected for EHDV-1 and 10 for EHDV-2. Six corresponding polypeptides of these 2 serotypes had different electrophoretic mobilities, indicating that these corresponding polypeptides differ in their molecular weights. A genetic relationship was not determined between the 2 EHDV serogroups and the blue-tongue serogroup viruses, using oligonucleotides mapping.     

Some factors in the separation of polychlorobiphenyls (PCB's) from organochlorine pesticides by column chromatography combined with gas-liquid chromatography

Retention volumes for polychlorobiphenyls (PCB's) and organochlorine pesticides have been measured on “Florisi”^b and silicic acid in various activity states using petroleum spirit eluant. The majority of organochlorine pesticides can be separated from PCB's by column chromatography. The exceptions areheptachlor, aldrin and BHC (apart from the gamma-isomer), and the separation of DDE from PCB's was only achieved with highly active silicic acid. With PCB residues normally found, the separations not secured by column chromatography were obtained by gas chromatography.     

Autoecological Studies on Mottra (Clinogyne dichotomy Salisb)

Clinogyne dichotoma , Salisb, belonging to the family Marantaceae, is a perennial crop with remarkable morphological characteristic. Present study on the anatomical features revealed their adaptability in waterlogged low-lying marshy lands unsuitable for the cultivation of any other crop.     

Seroepidemiological survey of maedi-visna virus infection in sheep and goat flocks in Quebec.

Maedi-visna, a chronic viral disease of adult sheep characterized by progressive dyspnoea or neurological manifestations, was first recognized and described clinically in Canada in 1970. Seroepidemiological study was conducted in sheep and goats in various areas of Quebec. Sera of 10% of the animals of selected flocks were collected and specific antibodies against maedi-visna virus were tested by a modified direct complement fixation test. Results show seropositive rate of 67.6% for Sherbrooke sheep; of 40.5, 41.1 and 47.1% for Quebec, Saint-Hyacinthe and Nicolet sheep respectively and only 29.2 and 20.0% positive sera in l'Assomption and Rimouski animals. Prevalence rate of positive goats varied according to geographic areas (0 to 36.8%). Statistical analysis of various factors, e.g. age, breed, mode of raising, origin and size of flock showed no relation between these factors and the geographic areas. But, some clinical problems in the sheep flocks such as cough, rapid breathing, mortality and abortion were associated with high infection rate (greater than or equal to 50%) to maedi-visna virus. In goats, no correlation was demonstrated between these clinical signs and serological results. Our results suggest that it is important to consider this disease in an adequate program of preventive medicine in Quebec.     

Cervical and Thoracic Vertebral Malformation ("Weak Neck") in Colombia Lambs

The purpose of this study is to describe a developmental defect of the caudal cervical and cranial thoracic vertebrae in 11 purebred Colombia lambs. The lambs were either affected at birth, or developed the condition within the first 18 days of age. Cervicothoracic kyphosis, with a compensatory cervical lordosis and ataxia were common; 8 lambs had abnormal head posture, characterized by inability to lift the head from the ground. One lamb had rigid head and neck, and had to move the entire body to look to the left or right. Neurological signs included ataxia, tetraparesis, diminished conscious proprioception, and increased patellar and triceps reflexes. One lamb had inspiratory stridor because of compression of the trachea in the area overlying the abnormal vertebrae (cervical vertebrae 6 [C6] and 7 [C7]). Radiographic and pathological abnormalities included malalignment and malarticulation of the caudal cervical and cranial thoracic spine, rounded cranioventral margins in the bodies of vertebrae C7 and T1, wedging of the intervertebral disc spaces between C6 and T1 vertebrae, and hypoplasia of the dens. Pathological changes in the soft tissues included hypoplasia of the cervical epaxial and hypaxial musculature, with associated focal areas of myodegeneration. Mild Wallerian axonal degeneration, compatible with a mild cord compression syndrome, was found in 3 lambs in the cervicothoracic spinal cord adjacent to the vertebral anomalies. The concentrations of copper and selenium in blood, plasma, or tissues were normal in 10 of 11 lambs. All but one of the lambs in which pedigree information was provided were genetically related. Siblings born as twins to 5 of the affected lambs were normal, but both lambs from one twin pregnancy were affected. Owners reported that breeding stock had been shared among the ranches. Because of the close familial relationships of the affected lambs, the condition is suspected to have a hereditary basis.