Tag Archives: Basset Hound

The Lymphoid System

The Lymph Nodes In dogs, the primordial structure of the largest lymph nodes is present at 35 to 38 days of gestation, and lymphocytic colonization of the nodes is prominent at 52 to 53 days of gestation (). At birth, puppies and kittens have readily recognizable lymph nodes with a loose reticular structure, low lymphocyte density, and limited organization into cortex and medulla that rapidly proliferates into cortical nodules and medullary cords. Lymph nodes and lymphatic vessels vary in location and number, but their primary function is to participate in immunologic reactions by filtering lymph and recirculating the lymphocytes (). Antigens that gain access to particular body tissues are ultimately found in lymphatic vessels that drain these tissues, making it logical that elements of the immune system are strategically positioned along lymphatic vessels. Although lymph node architecture is relatively uniform throughout the body, nodes near portals of entry of external antigens (mandibular and mesenteric lymph node areas) are often more reactive than nodes in other locations. Lymph Node Disorders As a major site of immunologic recognition, lymph nodes are expected to respond to various local and systemic inflammatory, Read more […]

Congenital and Hereditary Disorders of the Kidney

Structural Anomalies of the Kidney RENAL AGENESIS Renal agenesis is the complete absence of one or both kidneys. Bilateral renal agenesis is fatal and is a cause of early death in puppies and kittens (). Unilateral renal agenesis is more frequendy observed in puppies and kittens than is bilateral agenesis (). Unilateral renal agenesis may affect either kidney and is usually accompanied by ipsilateral ureteral agenesis. The etiopathogenesis of renal agenesis in dogs and cats is uncertain. A familial predisposition for renal agenesis in beagles, Shetland sheepdogs, and Doberman pinschers supports a genetic basis for the anomaly (Table 17-1). Unilateral renal agenesis may remain clinically silent, provided the contralateral kidney undergoes sufficient compensatory change to maintain normal hemostasis. Clinical findings may include an inability to palpate both kidneys or to detect a kidney by ultrasonography or contrast urography. Because of close associations in the development of the urogenital system, findings of abnormal or absent vas deferens, epididymal tails, or uterine horns at the time of castration or ovariohysterectomy should arouse suspicion of concurrent unilateral renal agenesis. Because unilateral renal 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 Anterior Uvea

The irides of the puppy and kitten are often a different color than those of the adult. The blue-gray iris of puppies and kittens usually changes to the adult coloration within a few weeks. Iris color is ultimately related to the degree of stromal pigmentation and is influenced by coat color. Congenital Abnormalities Persistent Pupillary Membranes. Persistent pupillary membranes are strands of tissue that arise from the anterior iris surface and represent remnants of an embryonic vascular system. The persistent pupillary membranes may be confined to the iris surface or may extend from the iris to the cornea or lens (). Persistent pupillary membranes are inherited in the basenji. Iris Cysts. Iris cysts are floating, fluid-filled vesicles that arise from the posterior iris epithelium and are usually found in the anterior chamber. Iris cysts may be unilateral or bilateral and singular or multiple in number. Pupillary Abnormalities. A notch-like defect (coloboma) is occasionally seen in the ventronasal pupillary border of young dogs and cats, resulting in a keyhole-shaped pupil. An eccentric pupil (corectopia) may accompany multiple ocular defects, as occurs in the Australian shepherd. Eccentric pupils are usually Read more […]

Epistaxis

Basic Information Definition Bleeding from the nasal cavity Synonyms Hemorrhagic nasal discharge, nosebleed Epidemiology Species, Age, Sex. Dependent on underlying cause: Young purebred animals: coagulopathies Young to middle-aged animals: infectious diseases, trauma Middle-aged animals: acquired immune-mediated diseases Older animals: neoplasia Genetics, Breed Predisposition, and Risk Factors Immune-mediated thrombocytopenia: young to middle-aged, small to medium female dogs Rickettsial disease: dogs living or traveling to endemic areas Thrombasthenia: otter hounds Thrombopathia: basset hounds von Willebrand disease: Doberman pinscher, Airedale, German shepherd, Scottish terrier, Chesapeake Bay retriever, and many other breeds; cats: Himalayan Hemophilia A: German shepherd and many other breeds; cats Hemophilia B: Cairn terrier, coon-hounds, Saint Bernard, and other breeds; cats Nasal lesions: – Aspergillosis: German shepherd, dolichocephalic breeds – Neoplasia: dolichocephalic breeds Contagion & Zoonosis Fungal infections (transmission potential appears low). Clinical Presentation History, Chief Complaint: (Some or all may be present.) Nasal hemorrhage Sneezing Pawing Read more […]

Classifying Aggression: Motivational Considerations

Significant debate surrounds the question of how to organize and classify the dog’s aggressive behavior into functionally discrete and logically coherent categories. Most trainers and counselors have adopted some variation of Moyer’s classification system () — a system that has resulted in a great deal of confusion and misunderstanding (). Other authorities have argued with varying degrees of cogency for a more simple classification system. O’Farrell (1986), for instance, has proposed a bipartite system, suggesting that canine aggression can be divided into two broad functional categories: dominance aggression and predatory behavior. This scheme places fear-elicited aggression under the same heading with dominance aggression: “‘Fear-biting’ is commonly distinguished from dominance aggression, possibly because it is felt to be understandable and excusable in a way that dominance aggression is not. It is, however, a variant of dominance aggression” (). Although simplicity is often desirable, this arrangement is not very edifying or useful when one considers the numerous motivational assumptions it takes for granted and the equally numerous distinctions that it blurs for the sake of Ockham’s razor. Further, the scheme Read more […]

Fundamental Behaviors of Dogs

The influence of human culture on the domestication of dogs evolved into man being the owner and the animal belonging to man, just like any object that can be bought, sold or even traded. This type of relation, even though replete with affection and positive interactions, began in the domestication stage and remains true today. The domestication process involves changes in morphologic characteristics and also drastically changes some aspects of behavior. When dogs (“wolf”) were wild, they had characteristics and needs that were suppressed and eliminated by human requirements to serve people. According to Hemmer (1990), the animal began to lose its original “perceptual world”. Behaviors such as rapid stress reactions for survival in the wild were overshadowed by characteristics such as docility, less fear and more tolerance of stress reactions. Domestication has led breeds to underdevelop certain important behavior traits such as intra- and inter-specific social behavior. The morphologic consequences are strictly related to the consequences of the behavior. Different physical traits exhibited in behavioral signaling among conspecifics were rendered impossible because of morphologic modification. An example is Read more […]

The Eyeball

The eyeball (bulbus oculi) is formed by three concentric coats: the fibrous tunic (tunica fibrosa bulbi), the middle vascular tunic (tunica vasculosa bulbi), and the inner nervous tunic (tunica interna bulbi). In the dog, the eyeball is nearly spherical, differing little in its sagittal, transverse, and vertical diameters. The size of the eyeball varies among breeds, but the diameter is usually approximately 20 to 22 mm. In one study, the radius of the canine eye varied across breeds from 9.56 to 11.57 mm and was correlated with the width and length of the skull. The transparent cornea forms the anterior one-fourth of the eyeball, and because it has a smaller radius of curvature (approximately 8.5 to 9 mm) than the rest of the eye, it bulges anteriorly. The vertex of the cornea is designated the anterior pole of the eye (polus anterior). The point directly opposite this is the posterior pole (polus posterior). The latter is a geometric point and does not correspond to the exit point of the optic nerve, which lies ventrolateral to the posterior pole. The line connecting the anterior and posterior poles and passing through the center of the lens is the axis bulbi. In the mesaticephalic dog the axis forms an angle of Read more […]

Ovaries: Estrous Cycle

Estrus in the bitch usually occurs twice a year, in the spring and again in the fall, although it may occur in any month of the year and may vary in occurrence from year to year. Sokolowski et al. (1977) report that Basset Hounds and Cocker Spaniels have mean interestrous intervals of approximately 5 months, whereas the German Shepherd Dog has the shortest interestrous interval, 149 + 28.5 days. The mean occurrence of estrus for the German Shepherd Dog is 2.4 times per year and for other breeds it is 1.5 times per year. Neither natural nor artificial light has any effect on estrus. Periods of sexual receptivity in the bitch can be recognized by behavioral patterns: lordosis, presenting to the stud, excitement of the stud, cytologic changes in the vaginal epithelium (blood cells and cornification as seen in a smear), visual changes of the vaginal epithelium as seen with an endoscope (), and more recently by hormone levels, particularly luteinizing hormone (LH) in the circulating blood (). The changes through which the nonpregnant uterus passes were designated by Heape (1900) as proestrum, estrum, metestrum, and anestrum. These terms were used by Evans and Cole (1931), Griffiths and Amoroso (1939), and other early investigators Read more […]

Discospondylitis / Osteomyelitis

Clinical signs: Spinal pain is the most common initial clinical sign in this disease, which is most frequently seen in large intact male middle-aged dogs. Although it can occur in any animal, the condition is less common in toy and chondrodystrophoid breeds of dog’, as well as in cats. Approximately 30% of dogs have signs of systemic illness such as fever and weight loss. Pathogenesis: Discospondylitis is due to infection of the intervertebral disc and adjacent vertebrae; if the infection is confined to the vertebral body, it is called vertebral osteomyelitis or spondylitis (). Staphylococcus intermedius is the most common aetiological agent of canine discospondylitis; other less commonly identified organisms include Streptococcus spp., Escherichia coli, Actinomyces spp. and Brucella canis, as well as Aspergillus spp. Young German Shepherd bitches seem to be predisposed to aspergillosis (), whereas young Basset Hounds contract discospondylitis due to systemic tuberculosis (). Haematogenous spread from distant foci of infection, penetrating wounds, surgery, or plant material migration can cause direct infection of the disc space or vertebrae, which is usually seen at the level of L2-4. Immunosuppression due to factors Read more […]