Cattle non infectious GI basics Flashcards
What is cheilognathoschisis
Congenital cleft lip
What is palatoschisis
Congenital cleft palate
How does palate fusion work and what implication does this have if we see a hard palate defect
Closure if from rostral to caudal
So any animals with a hard palate defect also have a soft palate defect
Which breeds of cow might have inherited midline fusion defects
Hereford
Charolais
Treating oral lacerations
Should heal without surgery; do daily lavage, antibiotis and NSAIDs
WHat organisms is mostly responsible for tooth root abscesses
Trueperella pyogenes
Signs and treatment of choke in cows
Signs = neck extension, drooling, no eructation, bloat, dyspnoea
Treatment = don’t feed/water due to aspiration pneumonia risk, resolve bloat, remove blockage
Where is the most common place for blockage; causes choke
Thoracic inlet
- May be foregin bodes inside oes
Could be extra-oesophageal e.g haematoma, abscess, tumour
What signs would we see with oesophageal trauma
Subcutaneous emphyema, anorexa, depression, swelling at site
- Should heal with antibiotics if no food leakage; larger perforations need surgery
What is oesophageal diverticulum
Acquired condition of oesophagus
- May be true diverticula i.e due to scar tissue or false due to defect in oesophageal musculature
Acquired condition: causes regurgitation, dysphagia, may palpate swelling in neck
How can we treat oesophageal diverticulum
Mucosal inversion and reconstrction; gives less risk of leakage post-surgery
Diverticulectomy: more risk of leakage and infection (cut off diverticulum and sew back up )
Which animals do we tend to see simple ruminal indigestion in
Hand fed dairy cattle, beed cattle
Due to variability in feed quantities
> Usually associated with sudden change in ruminal pH or physical impairment due to accumulation of indigestible feed
Treating simple ruminal indigestion
Stop feeding feed
Oral laxative/antacid
If too much urea/protein can give 5% acetic acid to correct the pH
Calcium parenteral
Transfaunation
Which microbes can be supplemented to enhance lactate use in rumen
And what can be used to inhibit lactate producers
Yeast are good at using lactate
Monensin sodium ionophore can be used to inhibit lactate production
what is subacute ruminal acidosis and when would we consider a herd at high rrisk
= intermittent periods of low ruminal pH (5.2-5.6) due to feeding excess rapidly fermentable carbohydrates and too low fibre
See herd effects: decreased milk production, poor BCS, unexplained diarrhoea
Consider herd high risk if >25% of animals tested have a ruminal pH less than 5.5
What complications can arise as a result of subacute ruminal acidosis
Caudal vena cava syndrome [via causing ruminitis and liver abscesses]
Laminitis
Unexplained diarrhoea
Management practices to avoid SARA
- Higher fibre: do 60:40 fibre: carbohydrate
- Gradual introduction of grain
- Supplement diet with yeast to use up lactate
- Add monensin sodium ionophores to inhibit lactate producing bacteria
Pathology of acute ruminal acidosis
Sudden drop in ruminal pH with acute clinical signs and risk of death
- introduction of rapidly fermentable carbs –> increase in gram +ves–> increase lactate production –> pH falls below 5 –> kills other organism, impairs motility of gut + increases osmotic pressure so causes fluid to move into the rumen
Dealing with severe acture ruminal acidosis (pH<5, HR >100, dehydration >8%)
RUmenotomy/rumen lavage immediately
IV fluids with sodium bicarbonate
Antimicrobials
NASIDS
Thiamine (to avoid CCN; polioencephalomalacia), calcium
What does a sluggish palpebral reflex indicate
High plasma D lactate concentrations
What are ruminal drinkers
Where calves on liquid diet get failure of reticular groove to work, so passage of milk into the rumen –> breakdown causes ruminal acidosis, hyper-D-lactaemia, metabolic acidosis
What does milky coloured, sour smelling rumen material suggest
Ruminal acidosis due to ruminal drinking (failure of reticular groove)
What is the cause of primary reticular groove dysfunction (ruminal drinkers)
Stress
WHich demographic do we see chronic ruminal bloat in
Calves <6 months
Probably a developmental defect
What is primary ruminal tympany/frothy bloat
= due to entrapment of normal gases from fermentation in stable foam
Get more stable foam with: soluble leaf proteins; or may get less salivary mucin (normally anti-foaming) on succulent forages
Also more gas on bloat producing pastures
Risk = high grain, legumine pastures/hay, young crops, veg crops
How to treat frothy bloat
Need anti-foaming agents; vegetable oil, polozalene, dimethicone, simethicone
MAy need to do emergency rumenotomy; or pass a rube
What is free gas bloat/secondary ruminal tympany
Due to physical obstruction of eructation
- Oesophageal obstruction, failure of eructation reflex (e.g in lat recumbency), tetanus, failure of oes groove
Will palpate gas on top of solid/fluid contents; high pitched pig
How to deal with free gas bloat
Remove obstruction
Pass stomach tube to immediately relieve bloat
Preventing pasture bloat
hArd; can drench with anti-foaming agents twice daily at milking, apply agents to field/water, do monensin slow release capsiles
What is ruminal parakeratosis
Where there is hardening and enlargement of ruminal papillae
Due to decreased ruminal pH and increase in VFAs in finishing cattle fed high concentrate diet
Or in calevs with prolonged ruminal acidosis
Causes reduced weight gain and ruminal tympany but usually identified post mortem
What neoplasias can affect the rumen/reticulum
- Fibropapillomas from bovine papillomaviruses 1,2,5
- Squamous cell carinoma; when bracken fern is ingested can get malignant transformation of fibropapillomas
- Lymphosarcoma from BLV or spontaneous
Can cause some interference with eructation depending on where mass is
What is traumatic reticuloperitonitis
Where sharp objects rae injected, penetrate reticulum wall and cause localised peritonitis
See anorexia, fever, milk drop, rumen hypomotility, +ve grunt test for abdominal pain
Treatment/prevention for traumatiic reticuloperitonitis
Treatment = administer oral magnet, antibiotics, NSAIDs; i this doesnt work go for surgery to look at peritonisit, lance abscesses, remove foreign body
TO prevent: give reticulo-ruminal magnet to all cows over 1 year and bulls, good disposal of waste, put electromagentic device in feed mixer
What are some complications of traumatic reticuloperitonitis
reticular abscesses
Traumatic reticulopericarditis
Traumatic reticlosplenitis (left) and hepatitis (right)
Diagnosing omasal impactin
Due to feeding tough fibrous feed esp wheat straw
See recurrent bouts of indigestion, pain response and hard distended omasum when palpating right hand side 7th-9th intercostal space
Increase in serum gastrin and motilin
Treating omasal impaction
Give mineral oil e.g liquid paraffin for a few days
If detected during rumenotomy, can pass tube into omasum and do a omasal flush to break up the impacted feed (knead through medial rumen wall)
What is Hofland’s syndrome
Vagal indigestion
Does vagal indigestion require damage to the vagal nerve
No
Some causes of vagal indigestion (categoried)
Vagal damage: trauma, megoesopahus/oes abscess, reticuloperitonitis, RDA or AV
Vagal impairment: mediastinal LN enlargement, neoplasia
Non-vagus: impairment of reticular/ruminal motility due to adhesions/abscesses, uterus limiting intestines in late pregnants, obstruction of any orifices b/w compartments with rope/placenta/masses
When would we do an atropine test (in relatino to vagal indigestion)
Where there is bradycardia and chronic indigestion
- TO differentiate whether bradycardia is vagal in origin or due to cardiac disease
If subcut atropine causes a significant increase in heart rate suggests some vagal nerve dysfunction
How can we use rumen chloride concentrations to distinguish between proximal stenosis and distal stenosis
PRox: 20mmol/l Cl-
Distal: 57mmol/L Cl-
When would we not bother surgery with vagal indigestion due to too poor prognosis
+ve atropine test
If it developed in days following RDA/AV surgery
When would we attempt to deal with vagal indigestion with guarded prognosis
Mechanical obstruction of reticulo-omasal orifice, reticuloperitonitis, abscesses,, later pregnancy
What are non-dietary cases/secondary impaction causes of abomasal impaction
Hypomotility in post parturient dairy cows
Mechanica interaction between pregnant uterus and abomasum
Vagal indigestion reducing motility.emptying
Traumatc reticuloperitonitis causing neurological or mechanics, obstruction of outflow from pylorus
Outflow disturbance due to abomasal volvulus, adhesions masses
Signs of abomasal impaction
Detect large firm mass on right flank palpatino
BIochem changes relating to reduces emptying: metabolic alkalosis, hypochloraemia, hypokalaemia,
Treating abomasal impaction
Minteral oil lubricant (could put this directly into abomasum via rumenotomy)
Laxative
Prokinetic
Induction of parturition
Are abomasal intraluminal obstructions common
No because the reticulo-omasal orifice works as a filter to large opjectsq
WHat is the basic principle of abomasal displacement syndromes
Reduction in abomasal emptying due to hypomotility or atony
–> Get gas accumulation causing abomasum to become buoyant and float dorsally
Key = reduction in motility + increase in gas
90% of time goes to left (LDA)
10% of time goes right (RDA or AV)
How can high concentrate feeding predispose to abomasal displacement
Ruminal content osmolality increases, draws water in and causes more rapid passage into abomasum
Get undigested material in abomasum and digestion leads to gas production
How does parturition predispose to abomasal displacement and at which stage do we see the different types
- ABomasum has been distorted by uterus
Post calving get freeing up of lots of space
Most RDAs/Avs seen post-parturitent; most LDAs seen in early lactation
Signs with LDA
mild drop, inappetance, change in faeces, less ruminal contraction, distended abdomen may be visible
High pitched ping + fluid splash on left side
Transrectal may feel that rumen has been pushed medially away from left body walll
Biochem: metabolic alkalsis, hypochloraemia/kalaemia
Is rolling a good treatment for LDA
No because recurrence very likely
What signs do we see in abomasal volvulus and how is it different to LDA/RDA
More acute onset and more severe
Much more distended abomasum; can see sprung rib cage; hear ping even cranially to 10th rib (covers 8th to 13th)
Colic, weakness, signs of shock and endotoxaemia due to ischaemia of abomasum ( can get necrosis), tachtcardai etc
Also see high L lactate
What would drainage of abomasal fluid/blood from an area of cellulitis suggest is going on
abomasal fistula has developed after ventral surgical or blind abomasopexy
Where do we see abomasal ulcers in adult cattle vs milk fed calves
In adult cattle = fundus
In calves = pyloric antrum
Grading abomasal ulcers basic
U1 = non-perforating with minimal haemorrhage (subdivided into a-d)
U2 = non-perforating with erosino of large blood vessel and massive intraluminal haemorrhage
U3 = perforating with local peritonitis
U4 = perforating with generalised peritonitis
U5 = oerforating into omental bursa, causing omental bursitis
What type of ulcers are more common in calves; bleeding or perforating
Perforating
Which microbes are important in abomasal tympany
Gas forming ones; esp clostridia
C perfringens A important
How does abomasal tympany syndrome/abomasitis/abomasal bloat/brazy-like disease work
Mild fed calves 2-6 weeks old
Related to large milk quantities at infrequent intervals or high glucose/salt solutions which delay abomasal empying
Get sudden filling of abomasum and delayed emptying which allows gas producting microbes to proliferate e.g C perfringens A so get gas build up and tympany
What is a good antibiotic with clostridial efficacy e.g for abomasal tympany syndrome in calves
Procaine penicillin
Which demographic do we tend to see abomasal trichobezoars in
Milk fed calves (veal); lack fibre
What is the difference between volvulus and torsion
Volvulus = rotation of viscera around its mesenteric attachment
TOrsion = rotation around own axis
Volvulus/torsion of the mesenteric root effects
Involves most of the intestine; leads to rapid ischaemic necrosis, cardiovascular shoc
High mortality
Volvulus of the jujunoileal flange
Dont commonly get arterial occlusions due to fat deposits; more so get venous occlusion; causes oedema, shunting of blood and then iscahemia
Signs relate to obstruction (c/f cardiovascular shock)
On rectal palpation feel distended intestine loops and excessive tesion on intestinal mesentery
What demographic is most commonly affected by intussusception
Calves <2 months old
Which area of the gut might we have to do manual reduction of intussusception due to difficulty of resection and anastomosis
Spiral colon
Signs of intussusception
Slowly appears over days; mild colic, anorexia, then pain subsides and get progressive lethargy and depression
On rectal feel distended loops of intestine; may feel intuscuception as a hard sausage like structure
How to treat an intussusception
Right flank laparotomy, exteriorise segment and do resection and anastomosis
Low survival
Dealing with intestinal entrapment
Cut the tight band; then check intestine for signs of ischaemia; if ischaemic should do resection and anastomosis
What is gut tie/pelvic hernia
Rare condition in castrated steeds/bulls where the cord forms obstructures that incarcerate the intestine; or traction can tear peritoneal fold of ductus deferens and allow loops of jejunum into pelvic cavity to get entrapped
When are we likely to see obstruction of small intestine/spiral colon by trichobezoars
When infected with lice/mange, during coat shedding, in cattle on low fibre diet e.g veal calves
What are classic biochem changes with any gut obstruction
Metabolic alkalsos, hypochloraemia, hypokalaemia
What demographic is caecal dilation/dislocation seen in
Dairy cattle during lactaton; may be related to hypoclacaemia
What is atresia colon and what signs do we get
= absence of a portion of the colon; usually ascending colon at midspiral loop
Likely due to vasculature compromise in early embryogenesis
[Seems to be inherited in holstein freisian studies]
In first few days of life see anorexia, abdominal distension, depression, absence of faecel, colic, tachycardia
Ultrasound shows intestinal ileu
Treatment for atresia coli
Anastomosis of proximal spiral colon to descending colon to create bypass
Poor prognosis
IF FPT involved then give plasma before surgery
When should we euthanise a cow with a rectal laceration
If there is a full thickness tear communicating with the periteonal cavity; will get septic peritonitis
Which demographic do we typically see rectal prolapse in
Feed lot cattle between 6 months and 2 years old
Classifying rectal prolapses
1 = just mucosa prolapses through anus
2 - complete prolapse of rectum layers
3 = complete prolapse of rectum layers + intussusecption of colon into the rectum
4 = Get some prolapse of intussuscepting descendign colon
What surgery might we do for a type IV rectal prolapse
Laparotomy, resectino of affected tissue and end to end anastomoses
What suture do we use to retain a rectal prolapse
Purse string; remove after a wekk
+ give topical lidocaine to stop straining
What is atresia ani
Heritable condition where no anal opening; can’t defecate and get subcutaneous bulge forming where anus would be
Do reconstruction under caudal epidural
What GI condition can fat necrosis lead to
Extraluminal obstructions
What might be described as ‘floating corks’ on rectal palpation
Fat necorsis masses
What are risk factors for fat necrosis
Overconditioning, lack of exercise, genetics (channel island cattle, japanese), fescue pastures (infected with endophyte neotyphodium coenophialum)
