equine and swine

horse overview

• small stomach with glandular and non glandular areas

• enlarged caecum produce lots of VFAs

• enlarged complex ascending colon

horse stomach

• 2 regions

• what separates

• type of epithelium

• what is the blood supply and where does this drain into?

• non glandular- keratinised stratified squamous epithelium

• margo plicatus

• glandular- ruggae and gastric pits, simple columnar epithelium

• gastric artery- blood supply.

• all gastric veins drain into hepatic portal vein

small intestine

• what are the 2 types of papillae and what empty

• has lesser papllea- lesser pancreatic duct empties

• greater papillae- greater pancreatic duct and bile duct empty

caecum

• what side

• main fermentation chamber

• right hand side of the body (rumen is left)

• ‘comma’ shape

• blind sac apex points towards the head

• folds

caecum development and what is the caecocolic orific

• strippled part is homologous with other species

• non strippled part is annexed first part of colon

• caecocolic orifice is a constriction of the ascendng colon

ileocaecocolic junction comparison

Horses: separated ileocaecal orifice and caecocolic orifice

Carnivores: major is ileocolic orifice and ileocaecal fold

liver

• bile is released slowly throughout the day

• no gall bladder

• only 4 lobes instead of 64 Lobes: Right, Left (Medial & Lateral), Quadrate, Caudate Lobe

• evident renal impression

spleen

• structure

• blood supply

• which part of the kidney is is connected to through which ligament

• elongated

• broad at base and narrow

• recieves blood from splenic artery which is a branch of the celiac artery

• part of spleen is connected to left kidney through the nephrosplenic ligament/renosplenic ligament

pancreas

• where does it open

• where is it embedded

• compare to carnivores

• opens in lesser and greater papilla

• embedded in mesentery- sits on top/within

• more lobulated than carnivores

what can be felt on renal palpation

• descending colon- ball of faeces

• caudal border of spleen

• nephrosplenic ligament

• caudal pole left kidney

• root of mesntery

• caeccum- base and ventral taenia

• pelvic flexture- a sharp, narrow hairpin turn in the horse's large colon where the left ventral colon folds back on itself to connect to the left dorsal colon, creating a bottleneck where food (digesta) slows down and can become impacted, leading to painful colic

• small intestine loops normally too soft but can feel ifdistended

• right kidney cannot be felt

colic and causes

• abdominal pain

• stretch of gut wall

• ischaemia

• inflammation

• build up of gas due to blockage of bloakcga itself

• torsion leading to tension in mesentery and cut off blood supply

• cn x damage can cause limited motility leading to gas accumulation

pig digestive tract overview

• simple stomach

• somewhat enlarged caecum

• complex ascending colon

• omnivores

development of the ascending colon in the pig

sphincters in equine stomachs- 2 types

• cardiac sphincter prevents reflux and vomiting

• pyloric sphincter controls outflow of the small intestine

what is the ansa spiralis

• coiled shape of the ascending colon

swine stomach anatomy

• 4 distinct areas

• oesophageal, cardiac, fundic and pyloric regions

• in oesophageal, ulcer formation occurs

• in cardiac portion mucus is secreted and mixed with digested food

• fundic region- gastric glands secrete hcl and also pepsinogen is secreted

• pyloric region- secrete mucus to line digestive membrane and regulates chyme secretion

A- the ileum

B- caecum

C- right ventral colon

This moves cranially and twists over to the left side to form a flexure called the sternal flexure.

D- left ventral colon

this then twists upwards from ventra to dorsal

E- pelvic flexure

F- left dorsal colon

this moves from the pelvic region cranially again to the right to form the diaphragmatic flexure

G- right dorsal colon which sits on top of the right ventral colon

H- transverse colon

I- descending colon

caecocolic orifice

cecum into ascending colon (right ventral colon)

caecal tympany

dilation of the caecum due to accumulation of gases

caecal impaction

fluid filled or solid filled in the caecum

solid filled: impaction of dehydrated ingesta.

fluid filled: functional failure of the cecum to empty

caecocolic intussucception

base of the caecum invaginates into the proximal part of the right ventral colon (ascending colon)

another simular condition to this is the caeco caecal, which intussusception results from uncoordinated peristalsis allowing the apex of the caecum to invaginate into the base. this is a relatively rare cause of colic, accounting for only 3-5 percent caecal disease in the horse