Tag Archives: Maltese

Anatomy and Normal Reproductive Physiology

1) When should I expect my male dog to be fertile? That depends on his breed. Animals of most species go through puberty and become sexually mature when they reach about 80% of their adult body weight. For a Maltese, that may occur when he is 4 months old. For a Leonberger, that may not occur until he is almost 2 years old. The only ways to know for sure that a male is fertile are either to breed him or to collect semen for evaluation. 2) My dog has poor libido. Does he have a testosterone deficiency? No. I have never documented lack of testosterone as a cause of poor libido in dogs nor has anyone else, to my knowledge. Embryology and anatomy of the male reproductive tract Determination of gender is dependent on the type of sex chromosomes present in the embryo. All dogs have 78 chromosomes, two of which are sex chromosomes; in females both are X chromosomes, and in males there is one X and one Y chromosome. Two tubular tracts are present in the developing embryo: the mullerian (paramesonephric) duct system, which goes on to form the female reproductive tract, and the wolffian (mesonephric) duct system, which goes on to form the tubular portions of the male reproductive tract. In the presence of a Y chromosome, Read more […]

Generalized Tremor Syndromes

Generalized tremors are surprisingly common in dogs (). This type of tremor can occur secondary to intoxications, drug therapies, congenital myelin abnormalities, storage diseases, encephalitis, or may arise without a definable cause. Degenerative diseases Lysosomal storage diseases Lysosomal storage diseases of the nervous system may have tremor as a presenting abnormality. Examples include globoid cell leucodystrophy, mannosidosis and gangliosidosis. The numerous storage diseases and their associated characteristic clinical signs have been described elsewhere (). Clinical signs: These diseases are often breed-related () with clinical signs first appearing in animals <1 year of age, but they can occur at any age. Many of these diseases involve the cerebellum and are associated with intention tremors. Pathogenesis: Accumulation of metabolic byproducts within neurons or the surrounding neuropil usually results from an inherited deficiency of a specific catabolic enzyme. The accumulation causes dysfunction of the cells and regions of the nervous system affected. Diagnosis: Ante-mortem testing for many of these diseases often results in negative or normal findings. CSF analysis is often normal, although Read more […]

Central vestibular diseases

Degenerative diseases Lysosomal storage disorders and neurodegenerative diseases Lysosomal storage disorders are inborn errors of metabolism in vhich specific deficiencies of degradative enzymes cause substrate accumulation and result in cellular and clinical dysfunction. Neurodegenerative disorders are diseases associated with an abnormality in the metabolic pathway that leads to early death of the neuron. Several of these conditions can present with ataxia and incoordination suggestive of vestibular disease. () Anomalous diseases Chiari-like malformations Chiari-like malformations are congenital defects characterized by caudal displacement of part of the cerebellum through the foramen magnum. This occurs as a result of occipital bone dysplasia causing the caudal fossa to become abnormal in size or shape. This malformation can cause compression of the brainstem and cerebellum, and result in signs of central vestibular disease. Neoplastic diseases Brain tumours Of the primary brain tumours seen in dogs, meningiomas and choroid plexus papillomas have a site predilection for the caudal lossa. As such, vestibular signs are commonly encountered in affected animals. Dermoid and epidermoid cysts are occasionally Read more […]

The faults and defects of the breeds: Toy Dogs

Affenpinschers Patella luxation, either medial or lateral; Legg-Calves Perthes disease Brussels Griffon Shoulder dislocation Cavalier King Charles Spaniels Patella luxation; Episodic weakness and collapse, a rare, inherited disorder Chihuahuas (Long and Smooth coats) Shoulders dislocation; Patella luxation, medial or lateral; Hypoplasia of dens, which produces atlantoaxial subluxation, causing neck pain and quadriplegia Chinese Cresteds Medial patella luation; Legg-Calves Perthes disease English Toy Spaniels (Blenheim/Prince Charles and King Charles/Ruby) Patella luxation, medial or lateral can occur with medial the most common, Congenital Femoral Shift Italian Greyhounds Predisposed to forelimb fractures Japanese Chin Dwarfism Maltese Patella luxatin Miniature Pinschers Shoulders dislocation; Legg-Calves Perthes disease; Epiphyseal dysplasia; Decreased long-bone growth; OIsteopenia Papillons Patella luxation Perkingese Hypoplaisa of dense (Odontoid Process, an atlantoaxial subluxation, causes neck pain and quadriplegia); IVD (intervertebrate disk disease); Swimmers syndrome; Atypical pannus; Legg-Calves Perthes disease Pomeranians Patella luxation, either medial or lateral; Dwarfism; Read more […]