Tag Archives: Golden Retriever

The Urinary System

Urinary tract disorders of puppies and kittens may result from heritable (genetic) or acquired disease processes affecting differentiation and growth of the developing urinary tract or from similar processes that eventually affect the structure or function of the mature urinary system. Successful management of urinary tract disorders depends on familiarity with the structure and functions of the kidneys, ureters, urinary bladder, and urethra. Developmental Physiology Although the embryonic kidneys produce urine, maintenance of fetal homeostasis is primarily the responsibility of the placenta. Varying quantities of urine formed by the fetal kidneys pass from the developing urinary bladder through the urachus to the placenta, where unwanted waste products are absorbed by the maternal circulation and subsequently excreted in the mother’s urine (). Fetal urine also passes through the urethra into the amniotic cavity, where urine forms a major constituent of amniotic fluid. The latter part of gestation is characterized by rapid increases in nephron number and size and by maturation of glomerular and renal tubular functions (). Prenatal development of glomerular filtration and renal blood flow appears to parallel increases Read more […]

Congenital and Hereditary Anomalies of the Ureters

Ureteral Agenesis Ureteral agenesis is the congenital absence of one or both ureters due to incomplete ureteral bud formation. Unilateral ureteral agenesis is the most common form observed in dogs and cats and is usually accompanied by ipsilateral renal aplasia (). Ureteral Duplication Ureteral duplication is a congenital disorder involving complete or partial duplication of one ureter. This disorder has been associated with a duplexed kidney and a supernumerary kidney in dogs; ureteral duplication has not been observed in cats (). Ureteral Valves Congenital ureteral valves are persistent transverse folds of vestigial mucosa and smooth muscle fibers forming annular, semiannular, or diaphragmatic lesions in the ureter (). Semiannular ureteral valves have been described in a 6-month-old female collie with unilateral ureterectasis, hydronephrosis, and urinary incontinence (). The etiopathogenesis of urinary incontinence associated with ureteral valves in this case is uncertain. Ectopic Ureters Ureteral ectopia is a congenital anomaly in which one or both ureters terminate abnormally in the urinary bladder. Intramural ectopic ureters contact and enter the bladder wall normally but continue submucosally through the Read more […]

Hypothyroidism

the commonest endocrine disorder of the dog the acquired naturally occurring condition has not been documented in the cat although the extremely rare congenital form has been described the metabolically active thyroid hormones are L-thyroxine (T4) and L-3,5,3-triiodothyronine (T3) Aetiology Primary congenital agenesis (rare) non-functional thyroid tumour (rare) lymphocytic thyroiditis; the most important cause (approximately 90%), an autoimmune disorder which results in thyroid destruction idiopathic thyroid necrosis and atrophy may represent the end stage of lymphocytic thyroiditis Secondary Less common than primary1 causes (less than 5%) TSH deficiency leading to inadequate stimulation of the thyroid gland with subsequent reduction in the production of thyroid hormone congenital hypopituitarism (usually in association with GH deficiency) pituitary neoplasia (may present with other signs, e.g. diabetes insipidus) Tertiary thyrotropin-releasing hormone (TRH) deficiency results in deficiency of TSH and reduction in thyroid hormone production due to hypothalamic lesions — extremely rare other equally rare causes of hypothyroidism include: iodine deficiency defects in thyroid Read more […]

The Eyelids

Developmental Abnormalities Eyelid Agenesis. Eyelid agenesis is a congenital defect of the eyelid margin resulting in absence of varying segments of the eyelid margin, palpebral conjunctiva, and fornices. The agenesis may be unilateral or bilateral, affecting the kitten more often than the puppy. The lateral one third or two thirds of the upper eyelid margin is most frequently involved. Keratitis and ulceration result from direct contact of the cornea with facial hairs and from exposure secondary to imperfect eyelid closure. Small eyelid defects may be successfully managed with ophthalmic lubricant ointments applied three to four times a day to reduce ocular irritation or by performing an entropion procedure to evert the offending hairs. If one third of the eyelid or more is missing, a pedicle graft from the inferior temporal aspect of the lower eyelid can be transposed to the upper eyelid. Distichiasis. Distichiasis is an extra row of eyelashes (cilia) that protrudes from the orifices of the meibomian glands onto the eyelid margin. The upper, lower, or both eyelids may be involved (). Congenital distichiasis often occurs in the English bulldog, toy poodle, miniature poodle, American cocker spaniel, golden retriever, Read more […]

The Globe And Orbit

Congenital Abnormalities Microphthalmos. Failure of the eye to develop to normal size is referred to as microphthalmos. Complete absence of the eye (anophthalmos) is extremely unusual in puppies and kittens. Microphthalmos is characterized by varying degrees of enophthalmos, with or without other ocular defects. Microphthalmos with multiple colobomas is an autosomal recessive trait linked to coat color in the Australian shepherd. In addition to small globes, affected dogs may have persistent pupillary membranes, cataract, equatorial staphylomas, choroidal hypoplasia, retinal dysplasia and detachment, and optic nerve hypoplasia. Vision is frequently impaired. Other breeds in which multiple ocular defects have been associated with coat color include the Great Dane, collie, Shetland sheepdog, and dachshund. Microphthalmos is also associated with inherited congenital cataracts in the miniature schnauzer, Old English sheepdog, Akita, and King Charles Cavalier spaniel. Microphthalmos occurs with retinal dysplasia in Bedlington terriers, Sealyham terriers, beagles, Labrador retrievers, and Doberman pinschers. Administration of griseofulvin to pregnant cats may produce microphthalmos in their offspring. Atypical Eye Position. Read more […]

The Lens and Vitreous

The lens develops rapidly in the early stages of embryogenesis, during which time it is nourished by the hyaloid vessel. The fully developed lens is avascular; by the second week of life, no remnants of the hyaloid system should remain. The normal lens often exhibits minor imperfections that can be easily detected with magnification in dogs and cats younger than 1 year. These include prominent anterior and posterior Y sutures and minute granules in its nucleus and cortex. A mosaic of brown pigment spots is occasionally seen on the anterior lens capsule near the center of the pupil, representing remnants of embryonic mesoderm. Disease of the vitreous would be expected to influence the lens or retina because of its attachments at the posterior lens surface and the optic disc. Congenital Abnormalities Congenital lens abnormalities include alterations in size or shape. Congenital absence of the lens (aphakia) is uncommon. In microphakia, the margin of the abnormally small lens along with elongated ciliary processes may be observed after pupillary dilation. Microphakia occurs along with other ocular defects in the Saint Bernard and beagle and in cats. Luxation of the microphakic lens may cause glaucoma. Lenticonus is a Read more […]

The Trachea and Major Bronchi

Cough is the most common clinical sign associated with tracheal and bronchial disease. Following a history and thorough physical examination to rule out infectious tracheobronchitis, thoracic and soft-tissue cervical radiographs may be indicated. Thoracic radiography is perhaps the single most important diagnostic test in the evaluation of the puppy or kitten that presents with cough as its primary complaint. Tracheal hypoplasia, extraluminal compressive diseases, diseases causing tracheal stenosis, intraluminal masses, and tracheal collapse may be apparent radiographically. Tracheoscopy with a small-diameter endoscope (approximately 3.5 to 5 mm in diameter or a rigid arthroscope) is useful in evaluating the trachea when obstructive or mucosal disease is suspected. It is especially useful in the diagnosis of tracheal collapse, tracheal foreign body, tracheal stenosis, parasitic tracheobronchitis, and tracheal osteochondroma. Congenital Disorders PRIMARY CILIARY DYSKINESIA Primary ciliary dyskinesia is a congenital respiratory disorder that is characterized by absent or deficient mucociliary clearance (). The ciliary dysfunction reduces mucociliary transport, which frequently leads to persistent or recurrent rhinitis, Read more […]

Pregnancy

Physiology and Endocrinology The eggs released by the bitch are fertilized in the uterine tubes and move into the uterus 8 to 9 days after ovulation. The conceptus implants and the placenta begin to be formed 16 to 18 days after ovulation. High concentrations of progesterone must be present throughout pregnancy. Progesterone during pregnancy decreases uterine contractility; stimulates secretions of the endometrial glands, which presumably provide nutrients to maintain the conceptus before implantation; and stimulates mammary development. Prolactin concentrations begin to rise at midgestation. Concentration of relaxin, released from the placenta, also rises beginning at midgestation (). The body of the bitch responds to the presence of the enlarged uterus and developing fetuses with processes designed to maintain function in the bitch while promoting development and growth of the puppies. Physiologic changes in the bitch that occur during normal pregnancy include the following: • Increased heart rate • Increased packed cell volume (% of the blood made up of red blood cells) • Increased oxygen consumption • Slower gastric emptying time • Increased blood flow to the kidney Superfecundation Read more […]

Intention tremors due to cerebellar disorders

Tremors that occur when an animal intends to move in a goal-orientated activity are most often the result of cerebellar disease (). Degenerative diseases Cerebellar cortical degeneration Cerebellar cortical degeneration, also termed cerebellar abiotrophy, is usually an inherited disease in dogs () with few reports in cats. Primary cerebellar cortical degeneration refers to degeneration and loss of Purkinje cells, molecular cells and granule cells. Clinical signs: These diseases are recognized syndromes in American Staffordshire Terriers, American Pit Bull Terriers, Kerry Blue Terriers, Gordon Setters, Rough-coated Collies, Border Collies, Brittany Spaniels, Bullmastiffs, Old English Sheepdogs and occur rarely in Samoyeds, Airedales, Finnish Harriers, Labrador Retrievers, Golden Retrievers, Beagles, Cocker Spaniels, Cairn Terriers, Great Danes, Scottish Terriers and others (). Clinical signs usually begin between 3 and 12 months of age. However, a subset of adult onset diseases occur with signs starting from 2-8 years of age in the Brittany Spaniel (), Gordon Setter (), Old English Sheepdog (), American Staffordshire Terrier () and Scottish Terrier (). Other signs of cerebellar disease that accompany cerebellar Read more […]

Aggressive Behavior

Characteristics of Dogs That Bite: Age and Sex The etiology of aggressive behavior presents considerable variation from dog to dog. Aggressive behavior is most frequently exhibited by socially mature and intact male dogs (), but young puppies can have serious precocious aggression problems, as well. Mugford (1984) reported that among 50 English cocker spaniels the mean average age of dogs with dominance-related aggression was 7.4 months (range, 3 to 24 months). In another group of golden retrievers treated by Mugford (1987), 24 with aggression problems averaged 2.9 years of age (range, 0.7 to 8.0 years). Of the 24 dogs treated by Mugford, 19 were males, two of which had been castrated. Beaver (1983) found that of 120 dogs with aggression problems (various diagnoses) the mean age was 3 years (range, 9 weeks to 11 years). She reported that 60.1% of the dogs were intact males (14% castrated), with 15.4% intact females (10.5% spayed). Wright (1985) found that the average age of dogs involved in severe attacks was 3 years (range, 0.67 to 10.5 years). All 16 dogs were males. These statistics suggest that considerable variation exists with respect to the time of onset associated with aggression problems. Although most dogs Read more […]