Pathology of The Alimentary System - Part 1, Oral cavity Flashcards
The Alimentary system varies in ?
its morphology and function in
different species.
E.g. neoplasia if alimentary system occurs more often in dogs and cats (small animal species). In farm animals, (pigs, ruminants, horses) especially food animals, infectious conditions are very common.
Dogs and cats develop ___________ _________ more often than farm animals
alimentary neoplasia
__________ and _____ develop a wide range of infectious diseases often poorly controlled by vaccination.
Ruminants, pigs
Horses are prone to intestinal ____________ → colic
displacements
Musculoskeletal conditions also occur often in horses.
Normal oral or gastro-intestinal mucosa should be ?
smooth and shiny.
If that is not the case, this may indicate that there is a problem.
What does feces serve as?
The quality and quantity of the
feces is often an early indicator of alimentary dysfunction, as is regurgitation and vomiting.
List the portals of entry of pathogenic agents.
Ingestion (most common)
- Sometimes pathogenic agent is coughed up from lungs, swallowed, and produces lesions in agent.
Coughed up by the lungs and swallowed
Systemic hematogenous route
Migration through the body (parasites)
What are the body’s defense mechanisms against pathogenic agents?
Saliva
- lubricates mouth and prevents bacterial from adhering to teeth and oral mucosa.
Resident flora and fauna
- compete with pathogenic agents
Gastric pH
- acidic –> harsh environment for most microbial survival
Secreted immunoglobulins
Vomiting
Intestinal proteolytic enzymes
Phagocytes and other effector cells within the mucosa/ submucosa
High rate of epithelial turnover
Increased peristalsis resulting in diarrhea
Define cleft palate and cleft lip.
1. What is an alternative name for this condition?
2. Are these conditions common? In what species?
3. Can both conditions be present in the same individual?
4. What causes this condition?
- Cleft palate (palatoschisis) and cleft lip (“harelip”- cheiloschisis).
2-3. Both are common, specially in calves as well as lambs, horses, dogs. - Both can be present in the same individual.
- Often a genetic disorder but toxins (e.g. ingestion of Veratrum californicum (found in california) and other teratogenic plants like lupines, poison hemlock in cattle & sheep) or maternal exposure to drugs during pregnancy (griseofulvin [antifungal] in queens and mares; steroids in primates).
What condition is pictured below?
What is a common complication of this
Cleft palate/cleft lip
Veratrum californicum
In palatoschisis there is a central defect in the midline fusion of the palatine
shelves resulting in communication
between the oral and nasal cavity.
Animal usually dies of aspiration pneumonia. Can not produce proper negative pressure when sucking in during nursing. Milk starts to spill out, especially through the nostrils.
What is the name of this plant? Where can it be found?
Veratrum californicum (found in california)
What condition is pictured below?
Cheiloschisis (“harelip”) - calf
Sometimes, this can be in combination with cleft palate.
What condition is pictured below?
Cheiloschisis, dog
What condition is pictured below?
Cheiloschisis, calf
Malocclusions are defined as?
What may they result in?
Failure to the upper and lower
incisors to interdigitate properly.
May result in difficulties in the
prehension and mastication of
food. Will not gain enough weight.
What condition is pictured below?
Short lower jaw (brachygnathia) = shortening of the mandible.
Also called brachygnathia inferior because it is shortening of the lower jaw. If shortening of the upper jaw it would be called brachygnathia superior. Brachygnathia superior is difficult to differentiate from prognathia.
What condition is pictured below?
Foal, prognathia → protrusion of the lower jaw. In this case, jaw appears to be longer than the maxillary area (upper jaw).
Define dental attrition.
Dental attrition (loss of tooth
structure caused by
mastication).
Carnivores: teeth similar to ours; enamel is confined to the crown of the teeth (outside the gums). Underneath lies the dentin. Enamel is produced by enamlobloasts, dentin produed by odontoblasts. Dentin is darker yellow in color. Cement.
Label accordingly.
The degree of tooth wear depends on what factors?
Abnormal wearing is common in species of THIS dietary restriction?
The degree of tooth wear depends on the tooth, the animal species and the types of food. Loss of dental function due to normal age- associated wear and tear is common in domestic animals. Abnormal wearing is most common in herbivores → results in “step mouth”.
- What condition is pictured below?
- This condition is common in older or younger individuals? Explain why.
- Abnormal wear and tear is common in animals with THIS dietary restriction.
- What happens if there is a problem on one side of an animal’s mouth?
Dental attrition
Normal in older individuals b/c you are using the teeth over time –> wear and tear.
Abnormal wear and tear of teeth = horses –> step mouth
If there is a problem on one side of the mouth –> dental attrition/step mouth.
Periodontal disease is caused by?
Resident bacterial films and the acid and enzymes they produce lead to enamel, gingival and periodontal ligament damage.
Dental plaque = composed of clusters of bacteria adhered to the teeth. Become attached to teeth. Placque = tartar. Can become mineralized and form calculus.
Dental calculus (tartar →mineralized dental plaque)
Bacteria attach to gingival crevices –> chronic periodontal disease.
What condition is pictured below?
Periodontal disease
Supragivngival plaque in crown leads to?
Subgingival dental plaque in crevices at root leads to?
Supragivngival plaque in crown –> cavities
Subgingival dental plaque in crevices at root –> chronic periodontal disease. Loss of alveolar bone.
- Are primary diseases of the oral cavity common? Explain why or why not.
- What is the exception to this rule ^ ?
2A. What species is this condition common in?
2B. What is a common complication of this condition?
- Primary diseases are rare.
- The exception is Actinobacillosis (Actinobacillus lignieresii)
→ chronic stomatitis – the tongue is often involved: “Wooden tongue.”
2A. Occurs primarily in cattle (occasionally in swine & sheep).
2B. Produces inflammation of the tongue called glossitis, stomatitis in general
can also produce inflammation of lymph nodes in region. Very rarely involves the bone.
What condition is pictured below?
Wooden tongue
Very large tongue with nodule lesions
Focal areas of ulceration
Pyogranulomatous type fo glossitis
What do you see microscopically in cases of wooden tongue?
A. lignieresii is a Gram-negative rod
Radiating clubs of amorphous eosinophilic material: Splendore-Hoeppli phenomenon= immune complexes surrounded bacterial clustere.
Large cluster of bacteria = pink thing
- What can be seen in this image?
- What is the causative agent?
- This is often seen in which species? At what age? What part of the body is affected?
- Thrush (Candidiasis)
- Candida spp. (eg. C. albicans) type of fungus
Often is observed in oral cavity (affects mucous membranes) of young animals, especially if they are immunosuppressed (Candida is opportunistic) treated with
antibiotics for long periods of time, or animals with underlying debilitating
diseases.
Involves the stratified squamous epithelium of the oral cavity & upper GI tract (including the forestomach of
ruminants).
Round structure = yeasts
Looking for fungal hyphae.
What can be seen in this image?
What is this caused by?
Ulcerative and necrotizing glossitis, uremia
Lingual lesions are often a manifestation of systemic disease like renal disease (uremic glossitis), BVD or other viral infections like
FMD (discussed later).
Diseases of the oral cavity can be caused by what?
Stomatitis - Etiology
Infectious agents
Trauma
Chemical injury
Auto-immune
Idiopathic