Week 2 Flashcards
what does the carnivore digestive system consist of?
stomach small intestine - duodeumun, jejuenum, ileum large intestine - ceacum, colon, rectum liver pancreas
what are the 4 layers on oesophagus?
mucosa, submucosa, muscalaris externa, serosa/adventitia
where does the osphogaus begin and finsih?
starts dorsal to cricoid cartilage and runs medial dorsal to trachea enters at Cardia of stomach.
what is the aortic arch and where does it belong?
a section of the aorta running between descending and ascedmning limbs of the aorta. runs along side part of the trachea and oesophagus.
what is peristalsis? and its uses?
basic propulsion of digestive tract contents. 1. constriction of lumen - by angular muscle fibres 2. propulsion - longnitidual muscle fibres 3. stimulation - external nerves and distension
what happens when a oesophageal obstruction occurs?
foreign body due to ingested material leads to suffocation of trouble swallowing
what is the mesentery?
where the peritoneum extends into cavity to wrap and GIT. provided access for vascular, nervous and lymphatic structures.
what are the 5 names of the mesentery attachments to. the GIT of carnivore
mesodurodemun mesojejunum mesoileum mesocolon mesorectum
what is the peritoneum and what does it do?
layer os mesothecila cells with a serous membrane and used to wrap around organs. contains two layer; parietal peritoneum visceral peritoneum includes; GIT, spleen, liver, pancreas, bladder, reproductive
what is the omentum (gastric mesentery)?
forms a ‘sac’ between folds = momentum bursa and causes fat deposition, momentum = serous membrane and used to isolate infection areas.
what blood vessels are involved in the digestive system?
aorta - Arteile supple to digestion system venous drainage - systematic vein to caudal vena cava - liver, terminal rectum hepatic portal system to liver includes GIT, pancreas and spleen.
explain the arterial supply craniely from abdominal aorta?
involves cranial mesenteric activity with pancreas, caudal duodenum, jejunum, ileum, caecum, Ann ascending and transerve colon.
explain the artier supply caudally form abdominal aorta?
C.D mesenteric activity, descending colon and rectum.
how is the systemic drainage system used for arterial supply?
systemic veins in terminal recturm = caudal vena cava, liver = caudal vena cave all other organs via hepatic portal system.
what is the Hepatic Portal system?
carries blood from digestive system to liver. connects systematic veins at periphery. Multiple potential routes for blood through portal system
what are the routes leading to the portal vein to liver?
Splenic vein - spleen, stomach Cranial Mesenteric Vein - DJI in small intestine Gastroduodenal Vein - pancreas, stomach, D Caudal Mesenteric Vein - colon, caecum, ileum
what is portosystemic shunting?
abnormal connecting between portal system and systemic circulation, bypasses the liver.
explain the sympathetic nerve supply for the digestive system?
via ganglia - coeliac craniale mesenteric caudal mesenteric the post ganglionic fibres run with artery decreased GIT activity
explain the parasympathetic nerve supply for the digestive system?
vagus (X) - craniel structures pelvic nerve - colon and rectum Increased GIT activity
what is the stomach?
consists - greater omenteum, lesser ometum gastrophetic ligament, lesser curvature and greater curvature
what are the different sections of the stomach?
fundus, cardia, pylorus, body and oesophagus
what are the 3 mucosal gland regions of the stomach?
gastric gland region pyloric gland region gland region
what is the need for the submucosa and mucosa?
submucosa = vascular plexuses and is very elastic mucosa = columnar epithelium covered in mucus
what is the pyloric sphincter?
makes a sharp transition in GI mucosa
how is the canine intestine layout?
S.I = Duodenum, Jejunum, Ilieum L.I = Caecum, colon, rectum
if you were to ultrasound the canine intestine what would you see?
intestine wall has 4 layers, Serosa, muscularis, submucosa, mucosa.
explain the features of the small intestine (DOG)
consists of DJI, for absorption and digestion products, lined with muscosa and submucosa up into plicate circulares. (especially in jejunum)
what is mucosa made up of?
finger like villi (V) with mucosa between called Crypts of Leiberkuhn (C) Microvilli are present at surface of columnar enterocytes (E)
what is the reason for microvilli and villi in mucosa in the S.I?
used to increase surface area for absorption
what is muscaularis mucaosae (MM)?
smooth muscle lined with villi, separated mucosa and submucosa.
what is muscularis external?
responsible for peristaltic activity in small intestine.
describe the Duodenum?
starts at the Pyloric sphincter, supported by mesoduodenum, first part of S.I, neutralises stomach acid and pepsin to allow for further digestion
what is the bottom of the descending called in the Duodenum?
caudal flexure
describe the Jejunum?
longest section, suspended by greater mesentery Histolgy - longer villi present, increase SA, greater absorption/ bulk absorption.
describe the Ileum?
shortest part of S.I, supported by greater mesentery and ileocaecal fold. contains ‘islands’ of villi that float in the lumen. contains lymphatic nodes and also has immunoprotection
explain the Large intestine?
used for recovery of water and salt from faeces. Propulsion of faeces to rectum for dedication. Fat soluble molecules/vitamines absorbed as-well. consists of Caecum, colon and rectum with 4 layers aswell, Serora, muscularis externa, submucsoa and mucosa.
what are the main differences between S.I and L.I?
L.I - has crypts but NO vili present Increased number of goblet cells (needed to secrete mucous)
how is the caecum positioned in the body?
small pouch at side of the colon Ileum carries to the colon.
describe the Colon?
supported by mesocolon, absorption of water and electrolytes. thinner walls that small intestine, does NOT have villi. muscular and serosal layers.
Name the 3 parts of colon?
ascending - short section between duodenum and mesenteric root transverse - runs right to left, caudal to stomach descending - longest part runs to pelvic canal, left of abdomen.
describe the Rectum?
intrapelvic part od L.I, supported by mesorectum. serosa reflects laterally into perietal peritoneum, stores faeces prior to excretion.
describe the Anal canal?
invagination of ectoderm,, very narrow lumen, internal anal sphincter - narrowing pf circular muscle of gut external anal sphincter - striated muscle under voluntary nervous control.
describe the Anal Glands?
small glands in mucosa and skin, paranal sacs, that contain small secretion expelled via single duct during defection. carnivores have them.
what is a disease that can occur due to last of opening/closing of anus?
Atresia, failure of a orifice or passage to develop or open. anal membrane/anal canal fails to open no faeces passed.
describe the Spleen functions?
storage of blood, lysis of RBCs, production of lymphocytes
what is red pulp and white pulp?
Red pulp - contains cellular blood, reservoir of blood cells. White Pulp - lymph nodules in reticuloendotheila frame.
what is the capsule in the spleen?
extends trabeculae into pulp, muscular in carnivores, some lymph vessels, contraction of capsule exiles blood cells into circulation (Stitch)
what supplies blood and nerves to Spleen?
Splenic artery and splenic vein sympathetic n.s and parasympathetic runs with arteries and veins.
describe the carnivore Spleen?
elongated, flattened, “dumbbell” shape. left cranial abdomen. head, body and tail of spleen sits to left of kidney and tail is ventral abdomen.
what is Halsted’s Principles?
be gentle to tissue, preservation of blood supply, min tension of tissue, accurate tissue appostose, dead space obligation.
what are the key factors when clipping for surgery?
sharp, clean on flat surface, clip 15-20cm around incision area, use white sticky roller to remove extra hair.
what solitons should be used for skin preparation for surgery?
chlarhexidine gluconate 2-3min contact time povidone iodine isopropyl alcohol sterilium
what method should be used for skin preparation for surgery?
use a target pattern. to and fro, work outward to drive bacteria away from incision site.
how should a surgeon approach getting into abdomen?
skin - contrious trunk muscle - external/internal abdominal oblique muscle - transverse oblique muscle peritoneum.
what are the five ways of entering the abdomen?
midline laparotomy paramedian laparotomy parainguinal laparotomy flank laparotomy laparoscopy
how should the abdomen wall be closed in surgery?
simple continuous suture - fast, easy to do simple interrupted - slower, multiple knots cruciate - slower, can be benefit with tension. subcutaneous closure - needs a simple continuous suture
what will happen if tissue layers are not closed properly?
meticulous haemoatisis
describe mastication?
reduces size of food particles moistens and lubricated food mixes with saliva food stimulates by pressure - sensory cells
what is the different between carnivore and herbivores mastication?
carnivores - allows cutting action herbivores - allows grinding action
what is saliva and what releases it?
saliva is 98% water, ions, enzymes used for lubrication, pH regulation, antibacterial, enzyme digestion. secreted form ACINUS, released form a salivary duct. saliva is hypotonic.
explain how swallowing occurs and where?
Oral cavity, pharyngeal and peristalsis food clumps together, stimulation of palate, swallowing reflex, causes opening of upper osphigeal sphincter and enters oesophagus, lower osphgeal sphincter relaxes and food moves into stomach. wave like contractions.
describe the stomach and the functions?
food storage, food with gastric juice, protein and starch, HCL kills bacteria, intrinsic factor secreted by gastric musical cells.
name the cells in the stomach?
mucin-producing cells-prodsate for HCL parroted cells - HCL intrinsic factor chief cells - pepsinogen neuroendocrine cells - histamine release