Digestive 2

Question 1

What are the functions of salivary glands

where are they found and what do they secrete

Answer 1

• moisten food (assists mastication)
• lubricate bolus (mass of food before swallowing) during deglutition (swallowing)
  • scattered salivary glands in lips, cheeks, soft palate and tongue
• secretions mostly mucous (carbohydrate-rich)
  • majority of saliva from distinct large salivary glands:
• secretions mostly serous (watery and protein-rich)

Question 2

List the 4 main salivary glands

Answer 2

1) parotid gland
2) mandibular gland
3) sublingual gland
4) zygomatic gland

Question 3

parotid gland where located, what species larger in, how does primary duct travel to oral cavity in different animals - what type of secretions

Answer 3

located superficially, ventral to ear
• larger in herbivores than in carnivores relative to body size
• primary duct travels to oral cavity:
- Carnivore - across lateral surface of masseter muscle in dog ⇒ opening in vestibule adjacent to upper fourth premolar tooth (pink in image number 1) - same opening in all species
- Herbivore - medial to ventral border of mandible in horse and ox ⇒ crosses ventral border of mandible laterally then goes through buccanator muscle ⇒ enters oral vestibule as for dog, horses only 3 upper premolars however many have a wolf tooth so still upper 4th premolar
purely serous except dog

Question 4

mandibular gland where located, larger in what animals, where does duct open - what type of secretions

Answer 4

Medial to parotid gland and much more superfical in the dog so more obvious to see, in horse underneath the parotid gland 
• located at angle of jaw
• deeper and larger in herbivores
• duct opens at sublingual caruncle
- mixed serous and mucous

Question 5

Sublingual gland - what parts where found and where does duct open - what type of secretion

Answer 5

2 parts - monostomatic (single primary duct) and polystomatic (multiple ducts) parts in most species right underneath the oral mucosa in oral cavity
• ducts run along floor of oral cavity and open adjacent to frenulum monostomatic in dog
- mixed serous and mucous

Question 6

Zygomatic gland where found, where does duct open, what type of duct system does it have

Answer 6

present in dog and cat lateral to the ear
• medial to zygomatic arch (in orbit)
• duct opens opposite last upper molar
• branching duct system:

Question 7

how does a duct system work what cells are involved

Answer 7

acinus ⇒ intercalated duct ⇒ striated duct (larger) ⇒ interlobular duct (in connective tissues between lobules)⇒ primary duct
• secretory cells arranged in acini (clusters of cells arranged around a lumen) surrounded by basement membrane
• contain serous or mucous acini (secreting cells), or both

Question 8

What are the types of acini and describe their structure and histology

Answer 8

Serous
• cells pyramidal - 2D triangles
• round basal nuclei
• basophilic perinuclear cytoplasm - protein rich
• secretory granules in apical cytoplasm
Mucous
• cells swollen with mucous secretions (carbohydrate - don’t take up H&E stain so clear) at apical part of cell which pushes nuclei basally
• flattened basal nucleus
Mixed glands
• individual acini composed entirely of serous or mucous cells, or both:
• serous demilunes (half-moon shape) in mixed acini

Question 9

the histology of intercalated ducts, striated ducts and interlobular ducts

Answer 9

Intercalated duct: low cuboidal epithelium, thin wall, variable cytoplasm - much less
Striated duct: columnar epithelium with basal striations due to alignment of mitochondria in cytoplasm, more cytoplasm than intercalated ducts
Interlobular duct: first simple columnar and as they merge towards primary duct becomes stratified columnar

Question 10

what innervation is involved with salivary gland secretion

Answer 10

• secretion under autonomic (parasympathetic) control:
o cranial nerve VII (facial) ⇒ mandibular, sublingual, buccal and zygomatic glands
o cranial nerve IX (glossopharyngeal) ⇒ parotid gland

Question 11

pharynx what group of muscles form the wall and innervation

Answer 11

constrictors, dilator, shortener

Motor and sensory: - contributions from cranial nerves IX and X (vagus).

Question 12

steps in deglutition

Answer 12

1) Bolus of food prepared by mastication and insalivation
2) apex of tongue pressed against palate
3) rapid contraction of mylohyoideus and extrinsic muscles of tongue (in brown) to propel food into pharynx
4) contact of bolus with pharyngeal mucosa sets off reflexes
5) soft palate raised, glottis (narrowest part of larynx) closed, hyoid apparatus drawn rostrally, pharynx shortened (by pharyngeal shorteners) - bolus doesn’t move but pharynx comes forward to engulf food
6) bolus moved into oesophagus by pharyngeal constrictors - rostral to caudal
7) wave of peristalsis within oesophagus conveys bolus to stomach

Question 13

oesophagus other name, function and structure

Answer 13

• also known as gullet
Function - to conduct food from the mouth to the stomach
Structure- simple muscular tube that runs from the pharynx to the stomach in 3 segments:
o cervical, thoracic and abdominal

Question 14

cervical segment of the oesophagus where is it located and what line does it follow

Answer 14

from pharynx to thoracic inlet (surrounded by 1st ribs, 1st sternebra and 1st thoracic vertebra)
o begins dorsal to cricoid cartilage of larynx (immediately rostral to beginning of trachea)
o follows trachea down neck, initially inclining to left
o medial to left jugular groove (over the surface of the jugular vein)
o returns to median position above trachea at about level of 1st rib

Question 15

thoracic segment of the oesophagus where is it located and what does it follow

Answer 15

o runs within mediastinum in thorax (mediastinum formed from membranes that separate thorax into two pleural cavities and surround unpaired structures such as heart, aorta and oesophagus)
o passes over base of heart (dorsal)
o crosses right side of aortic arch (beginning of aorta as it leaves heart)
o runs dorsal to bifurcation of trachea (branching of trachea into two bronchi)
o diverges slightly to left as it runs caudally in mediastinum ventral to aorta
o penetrates oesophageal hiatus of diaphragm (muscular structure separating thorax from abdomen)

Question 16

abdominal segment of the oesophagus where is it located and what does it follow

Answer 16

very short, especially in ruminant

once goes past diaphragm passes over dorsal border of liver (indenting it) to join the stomach dorsally at the cardia

Question 17

describe the structure of the mucosa of the oesophagus

Answer 17

thrown into prominent longitudinal folds, thus great dilation of tube possible - expansion of oesophagus
composed of 2-3 layers-
1) Epithelium stratified squamous - keratinised or non-keratinised, depending on species (depends on consistency of ingested food -usually keratinised in horse, ruminant and pig but not in carnivore - eating less traumatic substances less likely to damage lining of oesophagus)
2) Lamina propria - connective tissue layer
rich in collagen and elastic fibres; leucocytes; ducts of submucosal glands
3) Muscularis mucosae - in some cases thin layer of smooth muscle in mucosa at caudal end of oesophagus usually absent at cranial end (subject to species variation)- provides localised movement of mucosa

Question 18

describe the structure of the submucosa layer of the oesophagus

Answer 18

Loose connective tissue, mainly collagen and some elastic fibres

• rich in glands - produce mucus for lubrication - secretory cells like similar to mucus secreting cells in salivary glands
• contains glands at cranial end in most species (but along full length of oesophagus in dog

Question 19

describe the structure of the muscularis externa layer of the oesophagus - what types of muscle for different species

Answer 19

• muscle layer which moves food into stomach by contraction
• cranial and caudal oesophageal sphincters (constrict and stop movement of food through oesophagus at either end) suggested capable of maintaining intra-oesophageal intraluminal pressure higher than intra-gastric pressure.
• The caudal “sphincter” in the horse has sufficient tone that it usually remains closed during gastric dilation to the point of gastric rupture without vomiting occurring.) - horses unable to vomit
• Usually thickest layer of wall - Two layers of muscle - difficult to define at cranial end, but at caudal end obvious inner circular and outer longitudinal layers
• dog and ruminant- composed of skeletal muscle throughout; other species usually skeletal at cranial end - becomes smooth at caudal third in herbivores

Question 20

describe when the adcentitia and serosa are present in the oesophagus and what it is

Answer 20

Adventitia - where oesophagus lies outside thorax and abdomen; connective tissue merges with that of surrounding structures
o Serosa - where oesophagus lies within thorax or abdomen; connective tissues covered by epithelial layer - just a cavity surrounding

Question 21

blood and nerve supply to the oesophagus

Answer 21

Blood supply
• branches of common carotid, bronchoesophageal and left gastric arteries, depending on region
Nerve supply - autonomic
• branches of sympathetic and parasympathetic (vagus 10th cranial) nerves

Question 22

list the sites of possible obstruction in the oesophagus

Answer 22

1) Cranial and caudal oesophagus
2) Entrance to thoracic cavity - thoracic inlet
3) Over base of heart
4) Immediately anterior to diaphragmatic hiatus

Question 23

differences of the oesophagus in birds

Answer 23

o oesophagus is located on right side of neck in cervical region.
o crop - a saccular diverticulum (out pocketing) of oesophagus cranial to thoracic inlet.

Question 24

defence mechanisms in the oral cavity

Answer 24

1) saliva
2) resident flora
3) secreting immunoglobulins
4) phagocytes and offer effector cells
5) high rate of epithelial turnover
6) lysozyme and secretory phospholipase
7) taste buds that potentially reject toxic material based on taste and feel

Question 25

colour change of oral mucosa and possible reasons

Answer 25

black - normal melanin with age or melanoma yellow - jaundice white - anaemia blue/purple - cyanosis - decreased venous drainage - heart disease red - inflammation brown - systemic problems

Question 26

list the two types of facial clefts and why they occur and results of this abnormality

Answer 26

failure of fusion during embryogenesis Include cleft palate (palatoschisis) and cleft lip/hare lip (cheiloschisis) usually occur together. Palatoschisis is due to failure of closure of the lateral palatine processes of the maxillary bones. Important sequelae to the host are starvation due to inability to create a negative pressure in the mouth and resultant failure to suckle - generally when noticed and aspiration pneumonia (no effective separation between nasal and oral cavity).

Question 27

what is Brachygnathia - inferior Brachygnathia – superior Agnathia

Answer 27

short mandible “parrot mouth”. Top jaw overriding the bottom jaw. Occurs in cattle, sheep, horses and dogs. short maxilla. Heritable in dog, swine and cattle breeds. Progressive with age absence of mandible. Most common in lambs, usually associated with other facial abnormalities

Question 28

define stomatitis, glossitis, gingivitis, cheilitis, pharyngitis

Answer 28

stomatitis = diffuse inflammation of the oral cavity Glossitis - inflammation of the tongue Gingivitis - inflammation of the gingiva Cheilitis - inflammation of the lips Pharyngitis - inflammation of the pharynx

Question 29

define erosions, ulcers, vesicle, papule, granuloma

Answer 29

Erosions: partial loss of epithelium, forming a shallow indentation - doesn't extend into lamina popria - most superficial of the lesions Ulcers: full thickness loss of epithelium forming a deep indentation - in through basement membrane into submucosa and lamina popria Vesicle: A thin walled, raised, fluid-filled lesion, typically above basement membrane - can easily rupture and appear as a erosion which may become an ulcer - soft white to pink in colour, hard to find · Papule: raised flat topped lesion · Granuloma: collection of macrophages often surrounding a necrotic centre (inflammation)

Question 30

clinical signs of oral cavity inflammation

Answer 30

``` · anorexia · hypersalivation (ptyalism) · bad breath (halitosis) · reddening, swelling, exudates affecting the oral tissues (indicating inflammation) · ulcers, erosions, masses ```

Question 31

causes of stomatitis

Answer 31

``` Infectious agents Chmeical injury Auto-immune disease - in smaller animals most common Systemic disease Idiopathic ```

Question 32

causes of vesicular stomatidities

Answer 32

Causes are most commonly viral - cell lysis occurs which leads to a blister (vesicle - bulla is a vesicle larger than 1cm in diameter) then rupture leading to erosion or ulcer depending on damage and so body responds to cellular infiltration and then it heals, but also toxic and auto-immune.

Question 33

Foot and mouth disease from what family of virus what type of oral disease what species does it effect and what does it cause

Answer 33

Picornavirus - vesicular stomatidities - most economically important, extremely infectious effects ruminants and pigs - effects muzzle, oral mucosa, tongue, coronary bank on the hooves

Question 34

Vesicular stomatitis what family of virus, what does it affect and what does it cause

Answer 34

Rhabdovirus Infects horses, cattle, pigs, humans, lab animals, wildlife. Animals are bright and alert. Generally, only one foot is affected; primarily get extensive tongue ulceration that heals rapidly

Question 35

swine vesicular disease what type of oral disease what family virus belongs to what species found, clinical signs

Answer 35

vesicular stomatidities, picornavirus only found in pigs clinically indistinguishable from FMD vesiculo-erosive disease mainly affecting the feet, but can cause stomatitis, myocarditis and meningitis

Question 36

pemphigus vulgaris and pemphigus erythematosus what type of disease and what do they cause

Answer 36

vesicular stomatidities - auto immune disease damage the cement that holds individual cells together - generally attacks mucosal surfaces - around eyes and anus - can get vesicles and ulcers forming Vulgaris - most common Erythematosus - begin variant of the autoimmune disease

Question 37

Photoirritation what type of disase what causes it and what occurs

Answer 37

vesicular stomatidities Parsnip and some weeds have photoactive agent that when animals such as pigs rub it on themselves - if exposed to strong sunlight get photoactive dermatitis - on mucosal surface

Question 38

vesicular exanthema what type of disease, what family of virus, what species and clinical signs

Answer 38

vesicular stomatidities - calicivirus pigs only identical clinical disease to FMD

Question 39

characteristics of erosive and ulcerative stomatidities, causes and association with vesicular stomatidities

Answer 39

Ulcers are typically red and depressed. They are painful and often lead to excess salivation and/or decreased food intake. Causes include viruses, metabolic diseases such as renal failure and ingestion of irritating chemicals such as paraquat (herbicide). *Also with vesicular stomatidities, erosion and ulceration can occur; in those however ulceration/erosion is preceded by vesicle formation and rupture.

Question 40

Bovine viral diarrhoea virus (BVDV) what type of disease, how prevalent, what family of virus, pathology

Answer 40

erosive and ulcerative stomatidities - mucosal disease - flavivirus and endemic australia different forms depending on genotype of virus there is initial transplacental (in utero) infection of the early fetus with the non-cytopathic virus results in the birth of a calf that has a lifelong persistent viraemia (persistent infection). These calves (and only these calves) may later develop mucosal disease as a result of superinfection with a “homologous” cytopathic BVDV. In the field, mucosal disease usually affects animals of six to 18 months of age. In these animals, characteristic lesions include sharply demarcated erosions and ulcers in the tongue, gingiva, palate, oesophagus, rumen, abomasum and coronary band of the hooves. Severe diarrhea and frequently die

Question 41

Feline Calicivirus what type of disease, how prevalent, pathology

Answer 41

erosive and ulcerative stomatidities endemic disease in Australia. Generally, produces a respiratory disease in cats, but the condition may be complicated by oral ulcers that start out as vesicles.

Question 42

Bluetongue and Rinderpest what type of disease what animals effect, pathology

Answer 42

erosive and ulcerative stomatidities Bluetongue - sheep/cattle red/swollen muzzle, frothy exudate, congested oral mucosa, red/swollen lips and dental pad Rinderpest - ruminants and pigs - produces ulceration of oral cavity, lips, face, explosive diarrhoea - animals die quickly

Question 43

uraemia - what type of disease and what causes it, pathology

Answer 43

erosive and ulcerative stomatidities - metabolic causes systemic disease with secondary involvement of the tongue 1) renal failure - 2) uraemia (increase in blood urea nitrogen (BUN)) 3) vasculitis (inflammation of blood vessels) and thrombosis (blot clot) 4) necrosis of epithelium - generally of the tongue also produce nitrogenous waste that can change oral composition of the mouth leading to ulcers

Question 44

photosensitization what type of disease, what it effects, pathology

Answer 44

erosive and ulcerative stomatidities - metabolic causes This most commonly affects the skin but tongue may be affected as well if exposed to sunlight. Necrosis of the skin, Liver damage - looks like severe sunburn, underside of the tongue get exposed when licking sore parts of the nose and skin

Question 45

papular stomatidities what is the cause and the two types of diseases that result in these pathology of the disease

Answer 45

Due to Parapox viral infections, and include Orf (contagious ecthyma) of sheep and goats, and bovine papular stomatitis. - initially produce papillomatous lesions (wart-like) which become ulcerative, and then form proliferative scabs prior to healing, can scar and heal up ORF - In lambs may die as can't suckle properly

Question 46

feline lympho-plasmacytic stomatitis what causes it, what species, clinical signs

Answer 46

idiopathic condition of cats named on the basis of the histological appearance of the lesion. chronic condition characterized by red, inflamed gums, fetid breath, and inappetence. The oral mucosa is hyperplastic and ulcerated. Associations between this condition and the presence of bacteria or calicivirus associated with Feline Leukaemia Virus (FeLV) and Feline Immunodeficiency Virus (FIV).

Question 47

Eosinophilic stomatitis (Oral eosinophilic granuloma, rodent ulcer) what cause, what species, pathology

Answer 47

unknown but though to possible immune-mediated mechanism to flea antigens without oral cavity occur frequently cats rare in dogs Lip lesions are commonly visible near the philtrum and may extend through the adjacent haired skin. Oral lesions may occur anywhere in the mouth including gingiva, hard and soft palate, oral and nasal pharynx, tongue. - in dogs (rarely), more frequently in the lateral margins of the tongue. Histologically eosinophilic granulomas are characterized by eosinophilic, giant cell and mast cell infiltrate ulcer can eat into the face of the cat

Question 48

Deep stomatidities what do they produce what do they involve and causes

Answer 48

produce deep damaging ulcerations Deep stomatitides involve layers beneath the epidermis (connective tissue, muscle and bone). These can be due to viruses, bacteria, chemical or thermal injury. Conditions in domestic animals often become necrotic and include:

Question 49

oral necrobacillosis what type of disease what species occurs in what caused by, what called in calves, when most likely to occur, what does it generally start as

Answer 49

Deep stomatidities occurs in cattle, sheep and pigs calf diphtheria where it causes an acute, necrotizing ulcerative inflammation of the buccal and pharyngeal mucosa caused by fusobacterium necrophorum occur in outbreak in feedlot when on hard food stars as respiratory disease - leaves scars

Question 50

actinobacillosis - wooden tongue | what type of disease, occurs in what animals, due to infection of what, pathology

Answer 50

Deep stomatitides Occurs in cattle (also pigs and sheep), due to infection with Actinobacillus lignieresii which often gains entry through traumatic injuries of the mucosa - from abrasive food. It is a granulomatous inflammation (macrophages are the main cell infiltrate) and it affects lymphatics. Once develops tongue feels like wood

Question 51

Actinomyces bovis – lumpy jaw | what type of disease, what species occurs, due to what virus, what does it infect and pathology

Answer 51

Deep stomatitides Occurs in cattle and many species due mainly to Actinomyces bovis. The bacterium infects soft tissues of the oral cavity (connective tissue and muscle) and typically spread to bone, causing osteomyelitis (inflammation of bone). Inflammation is typically pyogranulomatous (macrophages and neutrophils)

Question 52

foreign body granulomas what type of disease what causes it and what occurs

Answer 52

Deep stomatitides Implanted foreign material eg plant awns can stimulate a focal chronic granulomatous response (macrophage rich) anywhere in the oral cavity, with or without secondary bacterial infection.

Question 53

Fibrous hyperplasia (Gingival hyperplasia) what type of disease, what occurs what species

Answer 53

Hyperplastic disease Benign overgrowth of gingival mucosa, which can be mild to severe where it buries the adjacent teeth. Common in brachycephalic dogs such as Boxer dogs. Grossly it is indistinguishable from other tumors in particular from epulides

Question 54

Epulides what type of disease, what are the two types and describe how they work, treatment

Answer 54

Hyperplastic disease Epulis = generic and clinical term for tumour-like masses on the gingiva. Can be hyperplastic or neoplastic (benign). the most common are the fibromatous and the acanthomatous. 1) fibromatous (characterized by submucosal proliferation of fibrous tissue) arises from the periodontal ligament and has a benign behaviour. 2) acanthomatous is characterized by proliferation of epithelium and has a malignant/infiltrative behaviour as creates cords that invade submucosa, lymph nodes and bone and can be destructive. Resistant to chemotherapy generally just surgical procedures

Question 55

Oral papillomatosis (warts) what type of disease, what species, pathology

Answer 55

Hyperplastic disease occurs primarily in puppies, and less so in foals, calves and rabbits. The lesions are transmissible and occur in young animals less than 1 year. Lesions are papilliform or cauliflower-like, white and friable and occur throughout the oral cavity and can go down into the oesophagus. Lesions usually regress spontaneously and immunity is long lasting.

Question 56

neoplastic disease of the oral cavity characteristics

Answer 56

neoplasms are usually malignant and can invade aggressively

Question 57

Squamous cell carcinoma (SCC) what type of disease, what species common, what occurs within those species where

Answer 57

neoplastic disease most common in older cats, also common in dogs. In cats, tumour is generally located on the ventrolateral surface of the tongue and generally ulcerate and can aggressively move into the submucosa In dogs, they are frequently located on the tonsils, and less commonly, the gingivae. arise from the squamous epithelium (lining) of the oral cavity

Question 58

Melanoma what type of disease, what species, characterised by, what caused by and the types

Answer 58

neoplastic disease most common oral tumour in dogs, over 90% are malignant, and most are considered to have metastasised (spread to other parts of the body) by the time of diagnosis to regional lymph nodes and lung. Characterised by rapid growth, with necrosis and ulceration common. arise from resident melanocytes of the mucosa; some tumors have pigment (melanin); a large proportion of oral melanomas doesn’t have pigment (amelanotic melanoma) so grey colours. Amelanotic forms are extremely malignant and generally not beign.

Question 59

Fibrosarcoma what type of disease what species, where occur, what shape and colour what arises from

Answer 59

neoplastic disease | Frequently seen in dogs

Question 60

problems with healing in the oesophagus and clinical signs of oesophageal disease

Answer 60

it lacks a serosa, therefore perforations due to foreign bodies will not seal themselves off, nor will sutures seal an incision. If have condition where mucosa and submucosa is infiltrated then holding power is really low of muscle so very difficult surgically to correct as also cannot be rested Clinical signs sinclude ptyalism (excessive production of saliva), regurgitation, vomiting, dysphagia, inadequate growth rate in young animals, weight loss and aspiration pneumonia.

Question 61

megaoesophagus two causes, what species, result from

Answer 61

Can be congenital or acquired, and occurs in dogs, cats and horses. Results from segmental or diffuse dysfunction of oesophageal musculature, producing a dilated, flaccid oesophagus. Uncoordinated or insufficient peristaltic movements mainly affect the mid and cervical oesophagus. Ingesta accumulate in the lumen and are regurgitated. results in a ventral displacement of the heart on radiography.

Question 62

what causes and results from congenital and acquired megaoesophagus

Answer 62

Congenital conditions are generally idiopathic - failed to develop the nerves needed. A specific cause is a persistent right fourth aortic arch. This results in oesophageal dilation cranial to the heart, whereas all other megaoesophageal conditions produce dilation cranial to the stomach. Occurs in dogs, occasionally in cats, rarely in other species. Acquired - may be idiopathic and/or attributable to neurological disorders, partial physical obstructions to stenosis, secondary to inflammatory diseases of oesophageal musculature. Specific disease conditions include lead poisoning, snakebite, neck trauma or brain stem disease.

Question 63

oesophagitis - what type of disease - what can it cause, what causes it and what can result from this

Answer 63

can be erosive or ulcerative and may be associated with ulcerative intraoral disease gastric reflux or exposure to irritant chemicals (paraquat, oak toxicosis). The most serious sequelae to chronic oesophagitis is stenosis (narrowing of the lumen) due to scarring. Superficial epithelial damage heals uneventful, but deep lesions produce scar tissue, which upon contraction leads to stenosis.

Question 64

choke how does it occur where does it occur, what can it lead to

Answer 64

oesophageal obstruction due to impaction, or is secondary to stenosis or motility disorders. Large, or inadequately chewed food material, such as potatoes, corn cobs, apples, bones - sharp, masses of grain, lodge in the oesophageal lumen. Commonly occurs where the diameter of the oesophagus is the smallest: larynx; thoracic inlet; heart base; anterior to diaphragm. Obstruction leads to mucosal damage (due to pressure necrosis and ulceration - allows access for pathogenic material into oesophagus and deeper tissues) which then leads to perforation and/or stenosis as fibrosis occurs

Question 65

oesophageal perforation how does it occur and what occurs

Answer 65

can occur with obstructive lesions or with ingestion of sharp foreign bodies (e.g. bones in carnivores). - Ulceration is worse as gone right through the wall so better access into deeper tissues

Question 66

List 3 parasitic diseases that occur in the oral mucosa, what species, where reside and what occurs

Answer 66

1) Sarcocystis spp = protozoa that parasitise striated and cardiac musculature of various herbivores such as sheep. Affected muscles include the oesophagus where ovoid, 1 cm long, white nodules project from the musculature - no pathogenic significance 2) Gongylonema spp affects ruminants, pigs, horses. They reside under the mucosa and can be seen as thin red serpentine structures. 3) Trichomonas spp commonly affect the oral cavity, oesophagus and crop of birds leading to formation of inflammation and formation of caseous plaques on the mucosal surfaces.

Question 67

oesophageal leiomyona what is it

Answer 67

tumor of the connective tissue