Anatomy Flashcards
Equine Anatomy
What side of the body does the equine stomach mostly lie on?
The left side
Equine Anatomy
What is the saccus cecus in the equine stomach?
the “blind pouch” where esophagus opens into stomach @ a tight angle
Equine Anatomy
What structure is the non-glandular part of the equine stomach in contact with?
The base of the spleen (gastrosplenic ligament)
Equine Anatomy
ID the hepatic lobes (equine) on the parietal surface
Equine Anatomy
What structure divides the glandular and non-glandular portions of the equine stomach?
Margo plicatus
Equine Anatomy
Describe the equine greater and lesser omentums
Greater: short & attached to transverse colon
- gastrophrenic lig. (cardia to crura)
- gastrosplenic lig.
- phrenicosplenic lig.
- renosplenic lig.
Lesser: hepatogastric lig. and hepatoduodenal lig.
Equine Anatomy
What is the suspensory ligment of the equine spleen?
the phrenicosplenic lig. + the nephrosplenic lig.
Equine Anatomy
How is the equine spleen in contact with the left kidney and the stomach?
Left kidney: nephrosplenic lig.
Greater curvature of the stomach: gastrosplenic lig. (part of greater omentum)
Equine Anatomy
Renosplenic entrapment in equines
when left colon becomes displaced//lodged within space formed by the renosplenic lig. (renosplenic space)
Equine Anatomy
Describe the equine liver:
- position
- features
- its attachment to the diaphragm
- located entirely within thoracic cage, mostly on the right side, and is completely overlapped by the lung
- NO right lobe divisions; NO gallbladder; NO papillary process of the caudate lobe
- right & left triangular ligaments continue bilaterally as the coronary ligaments -> converge into the falciform ligament -> attaches liver to diaphragm
Equine Anatomy
What are the portal ring and pancreatic ring in the equine pancreas?
The portal vein//portal ring perforates thru the pancreatic body -> the right + left pancreatic lobes fuse around the portal vein, forming the pancreatic ring
Equine Anatomy
Right versus left equine kidneys
Right: heart-shaped and in contact with caudate hepatic lobe (cannot be palpated rectally)
Left: bean-shaped
Equine Anatomy
Unique features of the equine kidneys
- Terminal Recesess (2 large collecting ducts in each kidney that drain urine from papillary ducts in each pole, into the renal pelvis)
- Mucous Glands (located in renal pelvis + proximal ureters that make equine urine a normal cloudy/frothy/turbid consistency)
Equine Anatomy
What is the hepatopancreatic ampulla cavity in the equine duodenum?
cavity in the major duodenual papilla where bile (hepato) and pancreatic ducts empty into
Equine Anatomy
What ligaments are present in the equine transverse duodenum?
the caudal duodenal flexure = transverse duodenum – surrounds the cranial mesenteric artery, caudally
- cecoduodenal lig.
- renoduodenal lig. (rt. kidney)
Equine Anatomy
Consequence of the equine’s long jejunum (22m) and long mesojejunum (4m-6m)?
prone to intussusception into epiploic foramen or tunica vaginalis (via inguinal canal)
22m = 60-70ft
Equine Anatomy
What is the significance of the ileal papilla in the equine ileo-cecal orifice?
Formed by this orifice, it is a muscular sphincter valve that contains a network of veins that, when engorged with blood, narrow the ileo-cecal orifice (act as a vascular sphincter) –> can become a site of INTUSSUSCEPTION
Note the cecocolic orifice as well, which is a slit-like, non-muscular-sphincter valve formed by two mucosal folds
Equine Anatomy
Describe the position of the equine cecum
- BASE = in right paralumbar fossa
- BODY = lies on abdominal floor
- APEX = points to xiphoid process
Equine Anatomy
What are the 4 cecal taenia (bands) of the equine cecum?
bands = thickenings of external muscularis
- Dorsal band = provides attachment for ileocecal fold (joins cecum to ileum)
- Lateral band = where the lateral cecal artery (LCA) is located, and provides attachement for cecocolic fold (joins cecum to asc. colon)
- Medial band = where the medial cecal artery (MCA) is located
- Ventral band = is free
Equine Anatomy
How can the equine cecum lose its blood supply?
If the cranial mesenteric artery or ileocecal arteries become obstructed (LCA and MCA originate from cecal br. of ileocolic a.)
Equine Anatomy
Equine Ascending Colon
- start/end
- order of structures
- surfaces
- Starts/ends @ cecocolic orifice/transverse colon
- RVC -> sternal flexure -> LVC -> pelvic flexure -> LDC -> diaphragmatic flexure -> RDC
- Ventral colons = sacculated; dorsal colons = smooth
Equine Anatomy
What tightly binds the equine transverse colon to the dorsal body wall? What fixes it to the ascending duodenum?
- transverse colon tightly bound to dorsal body wall via transverse mesocolon
- transverse colon fixed with the asc. duodenum via duodenocolic fold
Equine Anatomy
How can the equine descending colon be identified?
- Sacculated (fecal balls appearance)
- LONG descending mesocolon!
- 2 tenia
Equine Anatomy
Where are the potential points of obstruction in the equine GIT?
where sudden diameter changes; where flexures occur
- ileoceco orifice
- cecocolic orifice
- pelvic flexure
- diaphragmatic flexure
- transition from asc. to transverse colon
Equine Anatomy
Where is the epiploic foramen located in the horse?
At base of caudate hepatic lobe, bounded dorsally by caudal vena cava and ventrally by the portal vein & prt. pancreatic lobe
epiploic foramen = potential space of communication b/w peritoneal cavity and omental bursa in the right cranial abdomen
Is a SITE OF ENTRAPMENT!!
- Antegrade (R->L – more common) : jejunum herniates thru
- Retrograde (L->R – less common) : jejunum pushes greater omentum thru
Equine Anatomy
Describe the cranial mesenteric artery supply to the equine colon
- Colic br. supplies ventral colon (asc. colon NEAR cecum)
- Right colic a. supplies dorsal colon (asc. colon AWAY from cecum)
Equine Anatomy
Equine Verminous Arteritis
Strongylus vulgaris larvae migrate from the SI to the cranial mesenteric artery –> cause aneurysms, thrombosis, and obstruction of blood supply to portion of the SI or cecum –> necrosis
Ruminant Anatomy
ID stomach chamber and arrows
Bovine Rumen
- left arrow = ruminal papillae (present everywhere but the roof)
- right arrow = ruminal pillar
Ruminant Anatomy
ID stomach chamber
Bovine Reticulum
Ruminant Anatomy
What are the 3 openings of the ruminant reticulum?
1. Cardiac opening (@ 8th ICS)
2. Ruminoreticular opening
3. Reticulo-omasal opening (in lower right wall of reticulum)
Ruminant Anatomy
What view is this? What structures are removed? ID the numbers.
- Right view
- omasum and abomasum are removed
- Rumen
- Cranial ruminal sac
- Reticulum
- Reticulo-omasal opening
Ruminant Anatomy
In the bovine, the omasum is __?__ than the reticulum. In the small ruminant, it is the opposite.
In the bovine, the omasum is larger than the reticulum. In the small ruminant, it is the opposite.
Ruminant Anatomy
What is the position of the omasum on in ruminants/small ruminants? What covers it?
- Ruminants: Entirely on the RIGHT side. Covered by the lesser omentum.
- SR: Entirely on the RIGHT side but NO contact with Rt. body wall; the liver sits between/completely covers it
Ruminant Anatomy
Describe the interior of the omasum.
Papillated omasal laminae are arranged in four levels. In between laminae are interlaminar recesses.
Image:
- 31 = base of omasum
- 32 - omasal laminae
- 33 = interlaminar recessess
- 34 = papullae
- 35 = omasal groove
- 36 = omaso-abomasal orifice
- 39 = fundus
Ruminant Anatomy
Where is the Abomasum positioned?
- RIGHT side (7-11 ribs)
- directly contacts abdominal floor
- sits behind the xiphoid cartilage
Ruminant Anatomy
Where can the pyloric part of the abomasum be found?
On the right side in b/w greater & lesser omenta (which are attached to abomasum’s greater & lesser curvatures).
Ruminant Anatomy
What is the torus pyloricus?
a normal projection at the pylorus that may be mistaken for an obstruction lesion or a tumor.
42 = torus pyloricus
Ruminant Anatomy
ID red arrow
Omaso-abomasal orifice
- the two folds at the orifice form a valve: vela abomascia
Ruminant Anatomy
What is Right side Torsion of the Abomasum (RTA)?
Occurs with RDA
- RDA: damages vagal nerves (located along lesser curvature of abomasum) and twists them with the torus pyloricus –> leads to vagal indigestion
RDA: abomasum moves from ventral abd. to a position lateral to omental sling on cow’s right side
Ruminant Anatomy
ID the numbers
- dorsal curvature
- ventral curvature
- left longitudinal groove
- left accessory groove
- cranial groove
- caudal groove
- dorsal sac
- atrium
- ventral sac
- recess of ventral sac of rumen
- left dorsal coronary groove
- left ventral coronary groove
- caudodrosal blind sac
- caudoventral blind sac
- ruminoreticular groove (yellow broken line)
Ruminant Anatomy
ID the numbers
RIGHT side
- caudal groove
- dorsal sac
- atrium
- ventral sac
- right dorsal coronary groove
- right ventral coronary groove
- caudodorsal blind sac
- caudoventral blind sac
- right longitudinal groove
- right accessory groove
- insula ruminis
Ruminant Anatomy
Describe the attachments of the greater omentum
- Superficial layer @ LEFT longitudinal groove
- Deep layer @ RIGHT longitudinal groove
- Layers are continuous @ caudal groove
greater omentum runs over dorsal ruminal sac -> attaches spleen to rumen, attaches dorsal ruminal sac to sublumbar region -> stability
Ruminant Anatomy
Supraomental Recess
- location
- function
- A V-shaped hammock (omental sling) formed by the greater omentum
- is open caudally- where intestine can leave & pregnant uterus can enter
- Is the space in between deep layer of G.O. and the rumen
- provides a place for GI tract to sit in: jejunum/mesojejunum; spiral colon (to the LEFT of mesojejunum)
What structures of the GIT can be seen on right lateral view with an intact greater omentum?
Abomasum and descending duodenum
Where is the lesser omentum?
attached to the lesser curvature of the abomasum, covering the omasum
Clinical significance of the pig’s ear of the lesser omentum
Is a free slip that appears like a pig’s ear, which can be used in omentopexy and in ID of abomasum in LDAs
Ruminant Anatomy
What is the main blood supply to the ruminant stomach?
Celiac Artery
- splenic br., left gastric br., and hepatic aa.
Ruminant Anatomy
Gastric/esophageal groove
- location
- parts
- function
- Location: begins at cardia orifice (esophagus), goes thru the reticulo-omasal orificeand extends all the way into the abomasum, ending near pyloric region
- 3 Parts: reticular groove, omasal groove, abomasal groove (named after groove’s location as it extends)
- Function: When suckling animals feed on milk, the right and left lips of the reticular groove contract, forming the duct-like structure -> milk can bypass rumen and reticulum, avoiding abnormal fermentation
Ruminant Anatomy
Location of ruminant spleen
entirely on left side, firmly attached to craniodorsal aspect of rumen (via G.O.)
Ruminant Anatomy
Ruminant hemal nodes
receive and filter blood instead of lymph; found especially along the aorta; are dark brown in color
Ruminant Anatomy
ID organ and the two regions
Ruminant liver (pushed & rotated 90º by the rumen)
- Dorsal = RIGHT lobe
- Ventral = LEFT lobe
Ruminant Anatomy
ID the numbers on the visceral surface of the small ruminant liver
- Left lobe
- Papillary process of caudate lobe
- Caudate process of caudate lobe
- Cystic duct
- Right lobe
- Gallbaldder
- Quadrate lobe
- Renal impression
Ruminant Anatomy
What is the difference between the large ruminant and small ruminant pancreas?
Large Ruminant: NO pancreatic duct (major duodenal papilla is for common bile duct only), and the accessory pancreatic duct = main duct, opening @ minor duodenal papilla
Small Ruminant: DO have a pancreatic duct, opening with the common bile duct @ the major duodenal papilla
Ruminant Anatomy
ID 2, 3, 4, and 14
2. Sigmoid loop of the duodenum
3. Jejunum (on rt. side in supraomental recess)
4. Ileum (ileocecal fold = 6)
14. Mesenteric lymph nodes (found along attached border of mesojejunum)
Ruminant Anatomy
Where is the ruminant cecum located? Where is the apex directed?
In the right paralumbar fossa; apex directed caudally towards the pelvic inlet (different from equine cecum, where apex is directed toward xiphoid cartilage)
Ruminant Anatomy
ID the red, blue, and green parts of the ruminant ascending colon
red = proximal loop
blue = spiral loop
- a. inner = centripetal coils
- b. central flexure
- c. outer = centrifugal coils
green = distal loop
Ruminant Anatomy
What is unique about the descending colon in large ruminants?
The sigmoid shape // S-shaped curve just before the rectum starts
Ruminant Anatomy
Small Ruminant Intestinal tract: ID the numbers
- descending duodenum
- ascending duodenum
- jejunum
- cecum
- proximal loop of ascending colon
- spiral loop of ascending colon
- descending colon
- mesojejunum (recall the spiral loop lays on the RIGHT side of this)
- Ileocecal fold
Ruminant Anatomy
Describe position of the right bovine kidney
- Pendulous/floating: is suspended from abdominal roof by renal vessels, and is enclosed by fat-filled peritoneum
- Rumen pushes LK towards midline
Ruminant Anatomy
Bovine Kidney
- ID numbers 1-7
- What structres are missing?
- Lobe of kidney
- Cortex
- Medullary pyramid
- Renal papilla projecting into calix
- Minor calix
- Major calix
- Ureter
Bovine kidneys LACK a renal crest and renal pelvis!
No fusion of renal papillae (-> no renal crest)
No central urine-collecting chamber (-> no renal pelvis)
Ruminant Anatomy
Small ruminant kidney
- ID the colors
Pink = cortex
Orange = medullary pyramid
Blue = renal crest
Yellow = renal pelvis
Renal crest: formed by fusion of renal papillae, forming ridge (crest)
Renal pelvis: central urine-collecting chamber -> ureter
