Week 2 Flashcards

(158 cards)

1
Q

what does the carnivore digestive system consist of?

A

stomach small intestine - duodeumun, jejuenum, ileum large intestine - ceacum, colon, rectum liver pancreas

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2
Q

what are the 4 layers on oesophagus?

A

mucosa, submucosa, muscalaris externa, serosa/adventitia

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3
Q

where does the osphogaus begin and finsih?

A

starts dorsal to cricoid cartilage and runs medial dorsal to trachea enters at Cardia of stomach.

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4
Q

what is the aortic arch and where does it belong?

A

a section of the aorta running between descending and ascedmning limbs of the aorta. runs along side part of the trachea and oesophagus.

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5
Q

what is peristalsis? and its uses?

A

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

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6
Q

what happens when a oesophageal obstruction occurs?

A

foreign body due to ingested material leads to suffocation of trouble swallowing

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7
Q

what is the mesentery?

A

where the peritoneum extends into cavity to wrap and GIT. provided access for vascular, nervous and lymphatic structures.

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8
Q

what are the 5 names of the mesentery attachments to. the GIT of carnivore

A

mesodurodemun mesojejunum mesoileum mesocolon mesorectum

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9
Q

what is the peritoneum and what does it do?

A

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

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10
Q

what is the omentum (gastric mesentery)?

A

forms a ‘sac’ between folds = momentum bursa and causes fat deposition, momentum = serous membrane and used to isolate infection areas.

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11
Q

what blood vessels are involved in the digestive system?

A

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.

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12
Q

explain the arterial supply craniely from abdominal aorta?

A

involves cranial mesenteric activity with pancreas, caudal duodenum, jejunum, ileum, caecum, Ann ascending and transerve colon.

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13
Q

explain the artier supply caudally form abdominal aorta?

A

C.D mesenteric activity, descending colon and rectum.

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14
Q

how is the systemic drainage system used for arterial supply?

A

systemic veins in terminal recturm = caudal vena cava, liver = caudal vena cave all other organs via hepatic portal system.

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15
Q

what is the Hepatic Portal system?

A

carries blood from digestive system to liver. connects systematic veins at periphery. Multiple potential routes for blood through portal system

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16
Q

what are the routes leading to the portal vein to liver?

A

Splenic vein - spleen, stomach Cranial Mesenteric Vein - DJI in small intestine Gastroduodenal Vein - pancreas, stomach, D Caudal Mesenteric Vein - colon, caecum, ileum

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17
Q

what is portosystemic shunting?

A

abnormal connecting between portal system and systemic circulation, bypasses the liver.

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18
Q

explain the sympathetic nerve supply for the digestive system?

A

via ganglia - coeliac craniale mesenteric caudal mesenteric the post ganglionic fibres run with artery decreased GIT activity

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19
Q

explain the parasympathetic nerve supply for the digestive system?

A

vagus (X) - craniel structures pelvic nerve - colon and rectum Increased GIT activity

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20
Q

what is the stomach?

A

consists - greater omenteum, lesser ometum gastrophetic ligament, lesser curvature and greater curvature

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21
Q

what are the different sections of the stomach?

A

fundus, cardia, pylorus, body and oesophagus

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22
Q

what are the 3 mucosal gland regions of the stomach?

A

gastric gland region pyloric gland region gland region

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23
Q

what is the need for the submucosa and mucosa?

A

submucosa = vascular plexuses and is very elastic mucosa = columnar epithelium covered in mucus

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24
Q

what is the pyloric sphincter?

A

makes a sharp transition in GI mucosa

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25
how is the canine intestine layout?
S.I = Duodenum, Jejunum, Ilieum L.I = Caecum, colon, rectum
26
if you were to ultrasound the canine intestine what would you see?
intestine wall has 4 layers, Serosa, muscularis, submucosa, mucosa.
27
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)
28
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)
29
what is the reason for microvilli and villi in mucosa in the S.I?
used to increase surface area for absorption
30
what is muscaularis mucaosae (MM)?
smooth muscle lined with villi, separated mucosa and submucosa.
31
what is muscularis external?
responsible for peristaltic activity in small intestine.
32
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
33
what is the bottom of the descending called in the Duodenum?
caudal flexure
34
describe the Jejunum?
longest section, suspended by greater mesentery Histolgy - longer villi present, increase SA, greater absorption/ bulk absorption.
35
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
36
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.
37
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)
38
how is the caecum positioned in the body?
small pouch at side of the colon Ileum carries to the colon.
39
describe the Colon?
supported by mesocolon, absorption of water and electrolytes. thinner walls that small intestine, does NOT have villi. muscular and serosal layers.
40
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.
41
describe the Rectum?
intrapelvic part od L.I, supported by mesorectum. serosa reflects laterally into perietal peritoneum, stores faeces prior to excretion.
42
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.
43
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.
44
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.
45
describe the Spleen functions?
storage of blood, lysis of RBCs, production of lymphocytes
46
what is red pulp and white pulp?
Red pulp - contains cellular blood, reservoir of blood cells. White Pulp - lymph nodules in reticuloendotheila frame.
47
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)
48
what supplies blood and nerves to Spleen?
Splenic artery and splenic vein sympathetic n.s and parasympathetic runs with arteries and veins.
49
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.
50
what is Halsted's Principles?
be gentle to tissue, preservation of blood supply, min tension of tissue, accurate tissue appostose, dead space obligation.
51
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.
52
what solitons should be used for skin preparation for surgery?
chlarhexidine gluconate 2-3min contact time povidone iodine isopropyl alcohol sterilium
53
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.
54
how should a surgeon approach getting into abdomen?
skin - contrious trunk muscle - external/internal abdominal oblique muscle - transverse oblique muscle peritoneum.
55
what are the five ways of entering the abdomen?
midline laparotomy paramedian laparotomy parainguinal laparotomy flank laparotomy laparoscopy
56
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
57
what will happen if tissue layers are not closed properly?
meticulous haemoatisis
58
describe mastication?
reduces size of food particles moistens and lubricated food mixes with saliva food stimulates by pressure - sensory cells
59
what is the different between carnivore and herbivores mastication?
carnivores - allows cutting action herbivores - allows grinding action
60
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.
61
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.
62
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.
63
name the cells in the stomach?
mucin-producing cells-prodsate for HCL parroted cells - HCL intrinsic factor chief cells - pepsinogen neuroendocrine cells - histamine release
64
explain Hydrochloric acid secretion?
H+ ions formed in parietal cells, CO2 + H20 converted into HCO3- by enzyme carbonic anhydrase HCL contains pepsinogen.
65
why does the conversion of H2O + CO2 to HCO3- causes HCL to be secreted?
when HCO3- is produced it causes Cl- to pass into parietal cells, this causes H+ ions to move by A.T out into the gland lumen creating a concentration gradient in the lumen which causes K+ to move back into the parietal cells. CL- moves into gland lumen via diffusion and CL- + H+ bind to create HCL.
66
what is the purpose fo Chief cells?
store and release pepsinogen, pepsin is a stomach acid and hydrolyes proteins and breaks peptide bonds.
67
name the 3 substances that stimulate glandular cells?
ACh by cholingeric neurones Gastrin - from goblet cells Histamine - ECG cells stimulates Hydrogen pump.
68
explain gastric juice secretion?
vagal nerve stimulated of sight of food - triggers secretion of gastric juice via gastrin and secretory cells - food enters, distention + peptide stimulation by parietal and goblet cells
69
what is stomach churning?
food churned by waves in stomach, made into chyme, food mixes thoroughly, peristatlic weaves, force chyme formed
70
how is chyme expelled by stomach?
propulsion, grinding, retropulsion.
71
what are pacemaker cells?
interstitial cells of Cajal - produce spontaneous oscillators in stomach and intestine
72
what are the 2 types of signal for pacemakers?
Reflexes - short reflexes wall of stomach long reflexex by vagus nerve - EACh released - contractions - stomach expands - rapid emptying Gastrin hormone - secreted by epithelium cells of goblet cells - gastric contractions - reflex pyloric sphincter - gastric emptying.
73
what normally protects lining of stomach form HCL acid?
HCO3- and mucous form a protective barrier.. BUT if HCL breaks down barrier then stomach will produce 'gastric ulcers' common in equine and dogs
74
label this diagram
A-caudate process of caudate lobe B-left lateral lobe C-left medial lobe D-quadrate lobe E-right medial lobe F-right lateral lobe
75
label this organ
A - left lobe B - C - gall blader
76
label this section
A-sinusoids B-hepatocytes C-centr
77
label this image
A-papillary process of caudate lobe B-caudate process of caudate lobe with renal fossa C-right lateral lobe D-right medial lobe E-hilus or porta hepatis F-quadrate lobe G-left medial lobe
78
label this image
A-portal vein B-artery C-bile canuliculi D-hepatic vein
79
label this region of the abdomen
A-body of stomach B-small intestine and omentum C-liver
80
A-hepatic vein B-caudal vena cava
81
A-stomach B-L limb of pancreas C-pancreas body D-descending duodenum E-right limb pancreas
82
describe fatty degeneration of hepatocytes.
this is when instead of the fatty droplets within liver cells being transient, they are pernament - loss of functional liver tissue
83
describe what the liver is used for?
84
what is the liver capsule for?
85
explain the blood supply to the liver?
hepatic artery = 1/3 portal vein = 2/3 enters at hilus and both discharge into hepatc sinusoids
86
descibe what the Hepatic Lobules do?
hexagnoal shape, used for movement of blood form outside in.
87
what are hepatocytes?
**chief functional cells of the liver and perform an astonishing number of metabolic, endocrine and secretory functions. Roughly 80% of the mass of the liver is contributed by hepatocytes.**
88
how is Bile transported from hepatocytes?
transported to pheriphery of the lobule in the OPPOSITE direction of blood flow
89
what are the 4 major cell types in liver?
hepatocytes (HCs), hepatic stellate cells (HSCs), Kupffer cells (KCs), and liver sinusoidal endothelial cells (LSECs)
90
desicbe what Kepfter cells do?
91
descibe what Hepatic Stellate cells do?
store Vit A, producytion of extracellular matrix + collagen.
92
describe what the Billary System does?
**liver, gall bladder and bileducts, and how they work together to make, store and secrete bile**
93
describe the Gall Bladder
sac lined by non-secretaory simple columnar epithiulum
94
what does the presence of lipids cause in duodenum?
release of cholecystokinin is the presence of fat in the duodenum. Once released, it stimulates contractions of the gallbladder and common bile duct, resulting in delivery of bile into the gut.
95
describe the Pancreas?
exocrine - digestive system endocirne - humoral priduced by Islets cells L shaped organ, soft and slighly lobular
96
explain what the pancretic duct does? and the arterial/venous supply?
smaller duct, joins bile and runs into pudeuanl papillae somtimes abscent in dogs
97
what are hindgut fermentors and foregut fermentors?
Equine = hindgut (caecocolic) ruminant = foregut (gastric)
98
what does the Ruminant stomach consist of?
large, 4 chambers, take up most of abdomen, vascualr supply via coelic artery Reticulum Rumen Omasum Abomasum 60-100 litres in cow
99
descibe the Reticulum?
take drainage from oespsphagus, opening into omasum, muscosa - 1cm ridges with HONEYCOMB appearence small papillae
100
what is the reticular grove?
1. conveys milk from oesophagus - omasum - abosmasum 2. bypasses reticulum + rumen (milk would sit and curdle in rumen)
101
descirbe the Rumen?
largest chamber, subdivided into sacs by pillars dorsal and ventral sacs. Craniel seperation of dorsal sac - Artium Ruminis. Mucosa - papillated surface, increased SA for absorption of microsial digestion
102
what contratcion occurs in the rumen and what is it controlled by?
Primary contraction - biphasic reticular contrtacion allows for mixing! Secondary contraction - caudal - cranialm, RUMEN only, gas into oesphagsi and excrued. controlled by Vagus nerve.
103
how are ruminanats able to eat forgein bodies and not b affected?
forgein bodies can be forced through ruminorectiular wall by contraction. but can cause abseces and infection e.g) pericarditis
104
what is Suppurative Pericarditis
indiscriminate feeding of cattle. Objects become lodged in the rumen and are then forced by ruminal contractions into the reticulum and cranially into the diaphragm and pericardium. They may also penetrate the liver.
105
describe the Omasum?
the 'Bible' - 100 laminae layers sheets (thin like paper) covered in papillae, assit in movement of ingestion move and squeeze
106
describe the Abomasum?
sits on abdominal floor, feeds the omaso-abdominal opening, smooth, slimly lining, has a doubel layer of muscle present
107
which part of the stoamch is glandular?
only glandular part of stomach
108
what is the greater omentum?
dorsal of oesophagus, attaches to reticulum, abomasum and proximal deuoduemum.
109
110
what is the lesser omentum?
passes from visceral surface of liver to reticular groove, proximal dueodemum
111
explain the nerve supply for the omentum?
vagus nerve (cranial nerve X) parasymtoathic, dorsal vagal trunk - rumen wall, reticular groove, omasum, abomasum
112
descibe the Intetsines?
situated left of abdomen, complex coiling s.intestine and l.intestine
113
describe the Ruminent DJI?
Duodenum - runs vertically behind liver, supported by greater omentum Jejunum - multiply short coils, deep in stomach Ileum - short, joined to caecum by ileocaecal fold.
114
describe the ruminant Lage intestine?
Caecum - widest part, blunt, bind-ending sac into canal Colon - ascending transverse and descending colon, centrifugal and centperhieal aganist right flank. Rectum - wider and more muscleuar than desceding colon limits movement possible. Anal canal - mucsosal folds assist in closure, pelvic 'diaphram'
115
describe the vascular supply for intestines?
Cranial mesenteric artery - proximal duodemun for coelic artery, descending colon from mesenetric artery.
116
describe the venous drainage of intetsines?
portal system, mainly cranial mesenteric vein
117
describe the lymphatic draiange of intestines?
giant jejunal chains, with multipul nodes.
118
describe the Ruminant Liver?
left quadrate and rigjt caudal lobes. contains Gall bladder, vascualr supply = 1/3 hepatic artery (O2) 2/3 portal vein - rich blood for interstinal tract. blood drians via hepatic veins to vena cava
119
describe the Ruminant pancreas?
ventral to liver cows = one pancreatic duct enters duodenum distal to to bile duct. smaller ruminants = pancreatic duct enetrs with bile duct
120
describe how post-natal devopelment works for a milk diet?
ABOMASUM = 60% of stomach = biggest at birth. means milk must get to the abomasum via the reticular groove which transports milk bypassing rumen and omasum. at 2-3 weeks old - abomasum gets smaller, ruemn, reticulum and omasum 2x size. solid food adaptation from 3-8 weeks old
121
explain the equine GIT?
stomach, large and small intetstines, covered by ribcage, cardia - string sphincter and makes vommiting very diffuclt in horses. Margo Plicatus - gap between glandular and non-glandular areas.
122
name the 3 parts of the equine stomach?
fundas, body, pylarus
123
describe the S.I in equine?
short dueodenum, attached via mesentrary. major pancreatic and bile dutcs with surronding ampulla minor pancratic ducts, small papillae and concave margin.
124
describe the Equine Jejunum?
long mesentrary, left dorsal abdomen loops may lue between L.I
125
describe the equine Ilueum?
Very short, thicker wall that jejumn, opens into base of caecum.
126
describe the large intetsine (hindgut)
caecum ascending colon transverse colon descending colon rectum
127
describe the equine caecum?
Distal to ileocaecal junciton, caecocolic orifce - construction of colon, 1m long 30L capacity in large intetsine
128
what are Tenial bands/funciton?
external longnitudal muscle and elastic fibres into circumferal bands. gives L.I a sacculated appearance allows firm control of fermentaion
129
what are the 4 limbs of the large colon?
four limbs - right ventral colon, left ventral colon, left dorsal colon, right dorsal colon. to remeberr RVC comes first (like the vet school)
130
describe the pelvic flexure in the large colon in equine?
Narrowing of colon - Separation into sacs - Small particles pass - Water resorbed - Site of impaction - Palpable per rectum
131
describe the transverse colon and how it joins onto the small colon?
arises from right dorsal colon, passes in fornt of mesnetric root, small colon, Small sacculations form faecal balls
132
describe the Rectum and Anal canal in equine?
rectum become retroperitoneal, losses sacculation and widens before anal canal. anal canal closed by longnitdunal musocal folds
133
describe the arteial supply for the colon in equine?
all leads from the aorta - coelic artery - liver,spleen,stomach,pancreas etc cranial mesenteric artery - ileocolic artery, right colic artery (ascending colon), middle colic artery(transverse), jejunal and cd pancreaticoduodenal artery (pancreas and the lesser curvature of the duodenum) caudal mesenetric artery - left colic artery, craniel rectal artery. internal illiac artery - caudal rectal artery.
134
describe the equine liver?
in cranial abdomen, 2/3 midlien 1/3 otherside less dividied 4 lobes- left lobe, quadrate lobe, right lobe, caudate lobe NO GALL BLADDER pressent bile opens into major duodenal papilla.
135
describe the equine Pancreas?
largely right side of abdomen, attached to caecal base and right dorsal colon, has two opeings into dueodenum.
136
describe the Porcine GiT?
omnivores - very similar sturtures to dogs. elongated cone-shaped ascending colon and large caecum. GIT fairly lossly achored. lies in caudaventral abdomen.
137
describe the Porcine Liver?
simialr to dogs, Left lateral lobe L medial lobe Quadrate lobe R medial lobe R lateral lobe Caudate lobe
138
what are the 4 ways for CHO breakdown?
small intestine - pancreatic amylase enzymatic breakdown of dissaccarides into monosaccarides - enzymes on brush border of S.I Monosaccharides from enthrocytes into blood by facillaited diffusion. transport and upatke of glucose by target cells.
139
describe emulsificaiton of lipids?
triglycerides, phosopholipids and cholesroles. lipids = hydrophobic, lump together in S.I, broken down and held in suspension = emulfification
140
how are lipids broken down?
fat(lipids) broken down by bile acting as a detergent, lipids become coated in bile salts/phosopholipids. Chylomicrons - lipoprotein complexes (lipid+protein)
141
describe the breakdown of TAGs?
lingual lipase - seceted in mouth, lipid digestion in mouth. Gastric lipase - secreted in stomach Lipprotein lipase - releases fatty acids from lipids (TAGs) to tissues.
142
how does TAG digestion occur?
Pancreatic lipase attacks TAGs via gaps in chylomicrons = partial degernation. the TAGs are now bound to chylomicrons and can be taken up. TAGs are resynthesized with choletsrol + phosplipids = chylomicrons chylomicrons move by exocytosis into lymphatic system. Hydorlysised by lipoprotein lipase (LPL) LPL hydoryles TAGs to free fatty acids + glycerol (lipolysis)
143
descibe the exocrine pancreas structure and fucntion and how it contirbutes to digestion?
produces pancreatic juice for dogetsion. 2main cell types - interclated cells - secretion rich in HCo3- nutralises acidic content, provdes optinla pH for pancretaic enzymes - acinar cells - produces enzymes for breakdown of macromolecules.
144
what does pancreatic juice contain?
Proteases, endopeptidases, amylase, nucleases, lipase, bile salts
145
descibe the phases of pancreatic secretions?
cephalic phase - increases as food increwases, vagal activty increases for gastric release from stomach gatric phase - distention of stomach casues a relfex stimulating further secretion. intersital phase - chyme enters duodeum, causes vagal and hormonal signals depending on compostion of food
146
describe what secretin is and what its function is?
regualtes duodenum pH, inhitits gastric acid secretion from parietal cells, stimulates liver to produce bile. HCO3- production.
147
what is Cholecystolcinin (CCK)?
increased fatty acids and pepties, increase CCK. stimulates enzyme-pattened cells enzymes enhance prodiction - increases release
148
describe some difffernces betwene species in pancreas?
Ruminants - continually release pancreatic secretion after feeding at a constant rate Horses - contoinous 35L/day but increases after feeding, low enyme conc Cats/Dogs - little jouce secreted in S.I but increases vastly after feeding
149
descibe what the liver does?
produces bile by hepatocytes, and bile is stored in gall bladder. contaisn kupffer cells - star shaped macrophages bile secreted into S.I via bile canaliculi, nessasory for degenertaion and abosorption of fat.
150
explain the regulation of bile secretion?
conc of bile salts in portal blood ⬆️ ⬆️ in bile salt secretion ⬆️ bile production
151
epxlain why horses and ruminants do NOT have a gall bladder?
constantly digesting food and grazing, requires a constant supply of bile salts so gall bladder not required for storage.
152
explain how the small intestine motility occurs?
mix, ensure contact with membrane of epithial cells, transport chyme along digestive tract. types of movement = mix and segmentation = propulsive movements (peristalsis)
153
explain the regulation of motility?
interstitial cells of Cajal - pacemaker cells of inststial tract, produce action potenicals, which propogate from muscle cells via gap juncitons. Ileocaecal sphincter - ensuring expansion of L.I causes sphincter to close, emptying is a highly contolled process.
154
explain the large intetsine motility?
segmentation, peristalsis, retoperistalsis, mass movement (propel chyme to reaction) contractions regualted by instertial cells of cajal.
155
what happens when rectum is full?
distention stimulates stetch recpectors in the wall, can cause rectum to contract propusivily = mass movement
156
what is hindgut fermentation?
anerobic breakdown of fatty acids, high fibre feeds, pectin etc hind gut = caecum and colon. Hindgut functionally akin to the reticulo-rumen – importance of the microbiome! Hindgut = 85% efficiency cf. the rumen –Digestive efficiency in the hindgut of the horse: * 75-85% cell-wall CHOs * 15-30% soluble CHOs * 30% dietary protein
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what inflences the passage rate?
physical form of food, forage v grain physical form of food - parical size processing, growth stage
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