Margin to craton expansion of late ordovician benthic marine invertebrates

A biostratigraphic survey of 57 Late Ordovician marine shelly invertebrates from the Climacograptus manitoulinensis zone of eastern Canada supports suggestions that throughout the Early Phanerozoic benthic marine speciations occurred preferentially in marginal marine environments. The species subsequently spread onto the craton. There is no obvious positive correlation between the times of first appearance of new associations or novel communities along the continental margin and the first appearance on the craton of the species making up these communities. Taxonomic similarities between marine communities that occupied both marginal and cratonic regimes may reflect a more static local ecology than the evolutionary dynamics of a piecemeal species-by-species reassembly.     

Pemphigus foliaceus of the footpads in three dogs

Severe hyperkeratinization and villous hypertrophy of the footpads were seen in 3 middle-aged dogs. Peeling, fissuring, swelling, and ulcerations were noted on the margins of severely affected pads. Pain was evident in palpation and ambulation. Lesions were compatible with the traditional diagnosis of "hard pad disease". Histopathologic findings were diagnostic for canine pemphigus foliaceus in all 3 dogs, and direct immunofluorescence in an intercellular pattern was seen in both dogs that were tested. All 3 dogs responded to immunosuppressive dosages of corticosteroids.     

Radial-intermediate Carpal Bone Fusion in a Horse

The radial carpal and intermediate carpal bones were found to be fused in a four year old Quarterhorse stallion having a subtle forelimb lameness. Clinical examination, diagnostic local anesthesia, radiography and arthroscopy were used to arrive at the diagnosis. A cause could not be established, although perinatal deformation of cartilagenous carpal bone templates is suspected. A similar case of carpal bone fusion was found among carpi collected for an anatomical study, indicating this condition may be more common than expected. Clinicians should carefully evaluate the flexed lateral view of the carpus for proximal movement of the intermediate and ulnar carpal bones in young horses presented for carpal lameness. The significance of this condition will remain uncertain until its incidence and relationship to lameness are better defined.