RESUMO
External ear canal volumes of 50 dogs were measured by tympanography. Comparison between each dog's weight and ear volume revealed a linear increase in volume with increasing weight up to 10 kg. At weights greater than 11 kg, ear volumes did not increase. After ear canal measurement, the tympanic membranes of 30 of the dogs were punctured, permitting determination of the combined volumes of the external ear canal and middle ear. This combined volume increased with increasing weight.
Assuntos
Cães/anatomia & histologia , Meato Acústico Externo/anatomia & histologia , Orelha Média/anatomia & histologia , Testes de Impedância Acústica/instrumentação , Testes de Impedância Acústica/veterinária , Animais , Peso Corporal , Feminino , MasculinoRESUMO
The pattern of innervation of the caudal thoracic and cranial lumbar vertebral column of the dog is described. Frozen sections stained with Schofield's silver impregnation method show that the dorsal longitudinal ligament is profusely innervated, while the anulus fibrosus contains a few nerves limited to its outermost layers; no nerves are present in the nucleus pulposus. Following injection of horseradish peroxidase (HRP) into the anulus fibrosus of the thoracolumbar intervertebral disc and subsequent removal and staining of dorsal root ganglia, the reaction product is found in ganglia as far as two segments cranially as well as caudally, demonstrating that the disc is innervated by nerves arising from several spinal cord segments. A meningeal ramus, which innervates the discs of man, could not be found by gross dissection. Dissections show each vertebral articular facet innervated by the medial branches of two contiguous spinal nerves, a pattern further confirmed by injections of HRP into facet joints with subsequent staining of dorsal root ganglia. The dorsal rami of spinal nerves often divide into medial, intermediate, and lateral branches rather than the traditionally described division into only medial and lateral branches.
Assuntos
Cães/anatomia & histologia , Vértebras Lombares/inervação , Vértebras Torácicas/inervação , Animais , Feminino , Gânglios Espinais/anatomia & histologia , Peroxidase do Rábano Silvestre , Disco Intervertebral/inervação , Masculino , Nervos Espinhais/anatomia & histologiaRESUMO
In a survey of 250 dogs, a lymph node, designated buccal lymph node, was identified in 8.8% of the dogs examined. Anatomic features and drainage patterns are described.