Midsem 1 Flashcards

1
Q
Left displaced abomasum: 
presenting signs 
clinical signs 
risks 
Treatment
A

Presenting signs:

  • low milk after calving
  • gaunt appearance
  • failing to respond to tx
  • no appetite
  • loss of condition after calving

Clinical symptoms:

  • ping over 9-12th rib on left
  • rumen contractions decreased and rumen sunken in on side of cow
  • ketosis
  • small, soft faeces (+- diarrhea)
  • chronic; hypochloraemic, hypokalaemic metabolic acidosis
  • cannot palpate abomasum in rectal, possibly seen as sprung rib cage

Risks:

  • high concentrate/low fibre-> decreased rumen filling
  • first calf heifers (soon after calving)-> large void left by uterus (not taken up by rumen)
  • dairy
  • abomasal atony: hypocalcaemia- SM contractions and increased VFA
  • increased gases in abomasum- floats upwards
  • decreased rumen motility due to decreased fill and increased VFA causes abomasum to move upwards
  • omentum attached to abomasum stretched
  • decreased peri-parturient feed intake
  • not enough concentrates prior to calving-> papillae and microbes not adapted

TX:

  • rolling and blind tacking
  • SX: right or left paralumbar fossa omentopexy
  • left paralumbar fossa abomasopexy
  • right paramedian abomasopexy (recumbent)
  • oral or systemic calcium, oral electrolytes, oral propylene glycol, IV dextrose (ketosis), Antibiotics, NSAIDs
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2
Q
Right displaced abomasum: 
presenting signs 
clinical signs 
Risks 
Treatment
A

High concentrate/low fibre diet-> Abomasum becomes dilated (atony and accumulation of ingesta)-> dorsally displaced on right
Abomasum twists 180-270 anticlockwise around lesser mesentery->volvulus->irreversible neurovascular and lumen damage

Presenting signs:

  • adult dairy cows (few weeks to any time after calving)
  • not interested in feed
  • reduced/no faeces (+- diarrhea)
  • loss of body condition
  • not responding to other treatments

Clinical signs:

  • increased HR (80-90)
  • sudden abdominal pain
  • dull (no fever)
  • ping on upper right and splashing on lower right last five ribs
  • varying ketosis
  • reduced rumen contractions
  • dehydrated
  • hypochloraemic and hypokalaemic metabolic acidosis (trapped in abomasum)
  • rectal: can palpate in upper right quadrant. rectum empty cut can find autolysed blood

TX:

  • smasmolytic drugs, diet, calcium
  • right paramedian abomasopexy
  • right flank pyloropexy or omentopexy
  • incise, reduce abomasum, replace in abdominal cavity and three layer closure (first stitch including abomasum)
  • (L of paravertebral block) lignocaince, flunixin meglumine (analgesia), aftercare: oxytetracycline, oral propylene glyocol, electrolytes

PX: poor if >15% dehydrated, abomasum is necrotic, HR >120

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3
Q

Differentials for left sided pings

A
LDA
atonic gas 
pneumoperitoneum 
air in uterus (physometra)
check: 
- stomach tube- pH of contents 
- rectal exam (rumen contents) 
-
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4
Q

Differentials for right sided pings

A

RDA (dilation and volvulus)
Dilation, torsion or volvulus of caecum
Distention of proximal colon
Intestinal tympany- post-partum ileus, intussusception or torsion of root of mesentery
Torsion of coiled colon
Pneumoperitoneum, air in rectum and uterus

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5
Q
Abomasal ulceration
Types
Risks 
Clinical presentation 
DD
Treatment
A

Subclinical- erosions with no perforation
Ulceration with intraluminal haemorrhage
Perforated ulceration with local peritonitis
Perforated ulceration with diffuse peritonitis

Risks:

  • dairy cows 6 weeks post calving
  • dairy calves on bucket feeding
  • transition from milk to high fibre feeding
  • silage and concentrate
  • inappetence->low pH
Clinical signs: 
Severe: 
- inappetance and reduced rumen activity 
- low milk yield 
- intermittent diarrhea 
- pain (grinding teeth) esp. on palpation of lower right abdomen below rib 
- ketosis 
- loud fast HR
- fast shallow RR 
- pale mm 
- Weak and collapse 
- melaena (~24 hours) 

Localised peritonitis:

  • mild fever
  • significantly reduced milk
  • pain on right ventral abdomen
  • anorexia
  • reduced rumen activity

Acute diffuse septic peritonitis:

  • cold extremities
  • fast HR, RR
  • intense pain
  • recumbency, death

DDx:

  • intussuscetpion (decreased faeces and increased PCV)
  • duodenal ulceration
  • jejunal haemorrhage syndrome
  • acute traumatic reticuloperitonitis

TX: supportive

  • Iv fluids
  • NSAID contraindicated
  • blood transfusion
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6
Q

Causes of dietary abomasal impaction

A

High fibre (poor quality) in winter
- anorexia
- poor BCS masked by right abdominal distention
- increased RR, HR, expiratory grunt
- dry , scant faeces
DD: vagus indigestion, twins, hydroallantois, chronic peritonitis

Physical impaction: pylorus
large phytobezoars: chronic diarrhea and ill thrift
small phytobezoars: complete obstruction
- sudden milk drop
- gradual distention
- fluid splashing
- pasty and scant faeces

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7
Q

Abomasitis and abomasal distention

A

Uncommon. calves <1 month
Diffuse inflammation and gas accumulation

CS:

  • depression
  • rapid distention
  • high HR
  • colic
  • death

Risks:

  • too much milk
  • poor milk hygiene (clostridium perfringens)
  • irregular feeding times
  • milk temperature

Difficult to reduce with stomach tube

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8
Q

Calves: right sided abdominal distention DD

A

Right dilation and volvulus of abomasum
Abomasal bloat syndrome
Intestinal: torsion, intussusception or obstruction

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9
Q

Abominal examination

A
Visual
Palpate 
Auscultate 
Auscultate + percuss 
Ballot 
Auscultate + ballot 
Rectal 

Special:

  • grunt test
  • stomach tube
  • ruminocentesis
  • abdominocentesis
  • lab work
  • diagnostic imaging
  • ex lap
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10
Q

Ruminal indigestion
Pathophysiology
Risks
Clinical symptoms

A

Microbes not adapted (need 1-2 weeks)

  • wet feed
  • frost, overheated, sour
  • concentrates
  • antibiotics (kill microbes)
  • indigestible roughage

CS:

  • decreased rumen activity (tympany)
  • large doughy rumen
  • afebrile
  • anorexia
  • slight milk drop
  • small faeces and then malodourous
  • rumen pH <6 or >7
  • protozoa number and size in rumen decreased
  • multiple animals

TX;

  • spontaneous recovery
  • good hay
  • 1-2mg/kg epsom salts
  • gastric stimulant powder orally
  • Vitamin B

Prevent:
- gradual adaptation

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11
Q

Primary or frothy bloat

A

Lush, high protein legumes: rye grass, clover and lucerne
excess gas production and increased viscocity in rumen-> Gas bubbles trapped in foam->cannot erructate->cardia doesn’t relax and gas cannot escape to oesophagus

Presenting signs:

  • left paralumbar fossa distention 1 hr post feeding
  • abdominal pain: kicking, up and down, bellowing
  • one animal

Clinical signs:

  • rumen hypomotility
  • severe respiratory distress, tongue out
  • vomit frothy rumen contents

PM:

  • ab distension
  • blood tinged exudate
  • hemorrhage, oedema, congestion of muscles in head and neck
  • bloat line in oesophagus

TX;
- careful remove from pasture and supplement
If not lifethreatening: -> bloat oil (alcohol or pluronic based, or paraffin, mineral or vegetable oil)

If in severe resp distress: -> emergency ruminotomy (if large need sutures) + antibiotics
can pass tube easily but no gas
Prevention;
- gradual introduction to (genetically selective bloat safe) pastures
- antifoaming agents: tallow detergents, bloat oil, paraffin,
- alcohol ethoxylate- based preffered
- spray on feed, add in water, on flank, in blocks, oral

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12
Q

Secondary or gaseous bloat
causes
possibilities passing a stomach tube

A

Free gas trapped in dorsal sac of rumen
From physical or functional obstruction
Often chronic and recurrent o

Acute: physical obstruction, oesophageal groove (placenta)

Chronic: lesions affecting cardia (fibro-papillomas), reticulum (peritonitis, vagus indigestion) oesophageal groove (actinobacillus)

tetanus and hypocalacemia
calves following weaning
Recumbency- prevents erructation
Occasionally lesions compressing oesophagus: enlarged Ln and lymphoma

Tubing:

  • easily passed, no gas= primary bloat
  • cannot pass= obstruction
  • passed with resistance, release gas= oesophageal compression, distortion of cardia
  • passed easily, release gas= tetanus, hypocalcaemia, ruminal stasis, ruminitis, weak contractions due to ruminal distention
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13
Q

Per-acute ruminal acidosis

A

Ingestion of readily digestible carbohydrates and not enough saliva
- lactate (D and L) up to 300mmol/L (5 normal)
- defaunation of rumen fluid and overpopulation of G+ acid consuming lactic acid producing (lactobaccilus and streptococcus bovis)
- large amounts of VFA produced, overwhelm the pH regulators
- increased osmolarity in rumen, draws in fluid from EV-> dehydration
- Lactate absorbed in circulation->metabolic acidosis
Decreased pH->ruminal stasis and mild bloat

Fusobacterium can invade during chemical ruminitis->abscess to liver
Laminitis due to vasoconstriction

Risks:

  • digestion rate: wheat>barley>oats>maize>sorghum
  • not adapted to feed
  • fine milling

Clinical signs:

  • not eating, dull, ataxic
  • rumen activity low
  • HR up to 120
  • rumen distented
  • splashing and tinkling
  • colic and bruxism
  • rumen contents: milky green to brown- pH <5
  • malodourous diarrhea
  • Neruo: head pressing, staggering

TX:

  • 5-10L water + 1g/kg of alkalising agent and then every 12 hrs at 0.25-0.5g/kg
  • keep them moving
  • severe: rumenotomy and lavage
  • access to good feed, not water
  • procaine penicillin (rumen and systemic)
  • NSAID (endotox)
  • calcium borogluconate (hypocalcaemia)
  • Vitamin B- prevent PEM
  • Rumen transfaunation (3L)
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14
Q

Subacute ruminal acidosis

A

Sudden change in milk diet: increased starch and inadequate fibre
pH: 5-5.5
Proprionate and butyrate increasing and less acetate
Microflora mainly G-, G+ rising
VFA overwhelm absorption capacity

Herd signs:

  • intermittent diarrhea with undigested food particles
  • low milk fat
  • <50% less cud chewing
  • > 30% have rumen pH less than 5.5
  • laminitis

Ruminal fluid from oral or nasal intubation or rumenocentesis: 20 cranial to last rib at height of patella

Preventing:
- adaptation to diet
- adequate NDF (effectiveNDF >32% and forage supplies 80%)
high risk: buffers (sodium bicarbonate), neutralising agents (magnesium oxide), antibiotics (virginiamycin) and rumen modifiers (monensin sodium)

Putrefection:

  • sour feed ingested
  • rumen stasis, distension and alkalosis, mild tympany, ammonia smelling and foamy rumen contents,
  • milk gulped into rumen and putrefies
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15
Q

Traumatic reticulo-peritonitis

A

Foreign bodies:

  • sit on floor of reticulum
  • cause inflammation and mild clinical disease
  • penetrate and cause peritonitis
  • migrate into peritoneal and thoracic cavity-> vagus indigestion, pleurisy, abscessation

CS:

  • anorexia
  • sudden milk drop
  • mild ruminal tympany
  • arched back, abdominal tension, pain, grunt
  • 40-40.5 degrees
  • increase HR >90, vagus indigestion <70
  • shallow and rapid breathing
  • constipation
  • symptoms last few days and stop when fibrosis stops movement
  • neutrophilia + left shift
  • decreased protein: fibrin
  • lymphocytopenia

Pericardium involved:

  • oedema (ventral, submandibular and brisket)
  • muffled heart sounds
  • jugular vein distended
  • fluid splashing

TX;

  • week antibiotics
  • cage rest
  • rumen magnet
  • Exploratory laparotomy and removal
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16
Q

Vagus indigestion

A
Chronic onset 
Damage to vagus never, Mechanical restriction to Reticulum motility or oesophageal groove dysfunction 
- anterior peritonitis 
- liver or mediastinum abscess 
- fibropapilloma on cardia
- LN 
- ruptured diaphragm 
- actinobacillus on reticular wall 
- pleurisy 
- outflow problems (RDA, AV) 

CS:

  • papple shaped abdominal (forestomach) distention- ventral sac extends to right side- L shaped
  • gradual milk loss
  • bradycardia <50
  • poor BCS
  • pasty faeces, diarrhea, scant
  • froth in rumen
  • failure to
  1. obtruction to cardia or oesophagus
  2. failure of omasal transport
  3. failure of abomasal outflow

TX:

  • treat underlying cause
  • rumenotomy- explore
  • ruminal fistulations if chronic bloat
  • stomach tube to relieve distention
  • salvage slaughter
17
Q

Rumen fluke: paramphistomonas

A

No problem in rumen and reticulum as adults
Weakness, diarrhea and death in larval states migrating through SI and abomasum
Mainly younger animals
- Oxyclozanide

18
Q

Colic

A
Severe ruminal tympany 
ruminal acidosis 
Intussusception 
Phytobezoar 
Incarceration 
Volvulus 
Intestinal and abomasal volvulus 
Caecal tosion, volvulus and dilation 

CS:
- uneasy, treading hind limb, kicking at abdomen, up and down, twisting and turning, throwing themselves on the ground

Spasmolidic: spontaneous

  • observed in dairy cows at milking and calves at feeding
  • spasmolytic drug
19
Q

Abdominal pain not associated with GIT

A

Urolithiasis, pyelonephritis
Peritonitis
Photosensitisation
uterine torsion

20
Q

Intussusception
Presenting signs
Clinical signs
Treatment

A

Most common cause of SI obstruction
calves: diarrhea and strong straining

Presenting signs:

  • colic (sawhorse stance)
  • sudden drop of milk production
  • signs will decrease as the intussusception sloughs
  • scant faeces->blood and thickened mucous

Clinical signs:

  • distended right abdomen
  • rectal: empty but can feel distended loops
  • Increased HR, RR->normal->HR increases again
  • dehydration-> hypochloraemic, hypokalaemic metabolic acidosis

TX:

  • right flank laparotomy-> exteriorise and resect intussuscepted bowel with good margins -> cushings for end to end anastamosis-> flush with saline-> close
  • pre-op analgesia, paravertebral nerve block and antibiotics
21
Q

Intestinal volvulus

A

Calves 3-6 weeks old- red gut (rapid fermentation lactose forming gas)

Presenting signs:

  • sudden milk drop
  • colic
  • bilateral ab distention
  • occasionally right paralumbar fossa distended
  • normal and then scant or mucoid faeces

Clinical signs:

  • increasing HR
  • increased temp
  • rectal: distended loops
  • definitive Dc rare (fast progression)
  • dehydrated and recumbent (circ failure)
  • sudden death in calves

TX:

  • IV fluids and antibiotics
  • right paralumbar fossa- liberal incision
  • untwist volvulus
22
Q

Phytobezoars

A

Usually fibre balls in abomasum, can move to prox duodenum or any SI if small enough

Presenting signs:

  • colic
  • milk drop

Clinical signs:

  • green rumen fluid at nose
  • mayonaise like faeces
  • fluid splashing

Treatment:

  • right paralumbar laparotomy
  • paracostal nerve block
  • feel for pylorus and then down (commonly in ascending duodenum)
  • incise over ball, then use double inverting cushing, connell with 0-dexon, swaged on, round needle
23
Q

Trichobezoars

A

Hair ball in abomasal or blocking pylorus

- lice and winter coat

24
Q

Caecal dilation, volvulus and torsion

A

High concentrates, low roughage (or not adapted)
Undigested starches into caecam->VFA reduce motility ->lower pH-> gas trapped ->dilation (and displacement) or volvulus (apex moves cranially)
if impacted->torsion

Presenting signs:

  • high producing dairy cow within 60 days of parturition
  • reduced milk, feed intake
  • mild abdominal pain
  • reduced faeces

Clinical signs: dilation

  • right abdomen distended
  • ping from tuber coxae to rib 11
  • RECTAL: blind end of caecum into pelvic cavity pathognomonic
  • fluid splashing
  • normal rumination

Clinical signs: volvulus (more acute)

  • increased HR, RR
  • sharp milk decline
  • anorexia
  • ping in larger area than dilation (paralumbar)
  • rectal: distended caecum
  • dehydration
  • scant faeces

Medical TX for dilation only:

  • SX if >90HR, abdominal pain doesn’t subside
  • buscopan IV (spasmolytic) and calcium borogluconate withhold feed for 24 hours and then good quality hay

SX:

  • pre-op analgesia
  • right flank laparotomy
  • exteriorise and drain caecum (milk intra-abdominal portion towards incision)
  • close and replace
  • pull omentum over caudally

Torsion:
same SX, more difficult
- may need to resect devitalised tissue

25
Q

Jejunal haemorrhage syndrome

A

Risks: silage, high energy diets, lactation
Jejunum haemorrhage-> can clot and obstruct
sporadic and clusters

Presenting signs:

  • suddenly ill
  • anorexic
  • recumbent, systemic collapse
  • vocal, kicking, teeth grinding
  • abdominal distention
  • severe milk drop

Clinical signs:
- HR>100
- scant faeces, bloody
- dehydrated, pale mm, slow CRT- shock
- abdominal percussion: fluid splashing, low pitch ping
- rectal: distended bowel loops
PM: intestinal necrosis, jejunum distended with haemorrhage

DD:

  • acute diffuse peritonitis
  • salmonella
  • intussuscption
  • abomasal ulceration, haemorrhage and volvulus

TX:
- fatality high and PX poor

26
Q

Causes of many cases of acute diarhhoea, in young calves

A

Salmonellosis
Coccidiosis
Nematodes (GI parasites) + crypto and giardia
Nutritional accidents (e.g. toxins, rumen acidosis, molybdenum toxicity)
Iatrogenic (e.g. trace element overdosing)
Bovine viral diarrhoea (as an acute infection or as an outbreak of superinfection of PIs)

27
Q

Causes of sporadic acute diarrhoea in young calves

A

Salmonellosis
Yersiniosis
Mucosal disease
Malignant catarrhal fever- ovine herpes 2
Type II ostertagiosis (~18-30 months)•Clostridium perfringens(Type A)
Toxins: Arsenic, Salt, Mercury, Nitrate, Molybdenum, Mycotoxins (e.g. Fusarium)

28
Q

Causes of acute diarrhea in many cases of adults

A

Salmonellosis
Winter dysentery
Dietary: Copper deficiency, Acute copper toxicity, Cobalt deficiency, Selenium deficiency, Lush, rapidly growing pasture (low NDF) –NZ
Rinderpest (not any more)
Nutritional accidents (e.g. toxins, rumen acidosis, molybdenum toxicity)
Iatrogenic (e.g. trace element overdosing)

29
Q

Causes of acute diarrhea in sporadic cases of adults

A

Salmonellosi
Yersiniosis
Toxins
Diarrhoea not associated with enteritis: Diseases of forestomachs or abomasum, Toxaemia, Hepatitis, including chronic fasciolosis, Ragwort poisoning, Peritonitis, Congestive heart failure (RHF), Renal amyloidosis

30
Q

Causes of chronic diarrhea of many cases

A

Parasitism (younger animals)
Copper deficiency (often younger animals)
Salmonellosis
Selenium deficiency

31
Q

Causes of some cases of chronic diarrhea

A

Parasitism (younger animals)
Mucosal disease (younger animals)
Salmonellosis
Ragwort toxicity

32
Q

Chronic isolated cases of chronic diarrhea in aged animals

A

Toxaemia, peritonitis
Endocarditis
Diarrhoea associated with chronic passive congestion
Hepatitis
Renal amyloidosis
Bracken fern-induced alimentary carcinoma (rare)
Enzootic bovine leukosis (lymphosarcoma –enteric form)

33
Q

Diarrhea and its pathogenesis

A
Intestinal malabsorption: 
oosmotic; e.g. grain overload 
exudative; e.g. salmonellosis
secretory; e.g. enterotoxigenic E. coli
abnormal intestinal motility

Result in dehydration, and electrolyte and acid-base abnormalities
Age related-> type II ostertagiosis)

34
Q
Salmonellosis 
Types 
Source and risks 
CS 
Syndromes 
TX 
PV
A

Salmonella typhimurium:

  • predominant species affecting cattle in Australia
  • not host specific
  • enteritis
  • carriers for 3-4 months

Salmonella dublin:

  • host-adapted to cattle (not a zoonotic risk)
  • latent carriers- lifelong

Salmonella brandenburg:

  • sheep in New Zealand-> cattle
  • acute enteritis and septicaemia, abortion (disease in humans)

S.morbificans and S. hindmarsharealso, (NZ.) S.bovismorbificans, S.montevideo, S.newport, S.zanzibarand

Source: faecal-oral

  • infected animals, chronic carriers
  • water, feed
  • aborted material
  • environment
  • in macrophages, LN

invade enterocytes-> inflammation-> malabsorption and maldigestion

Risks:

  • overcrowding
  • Sudden dietary changes
  • Concurrent infections –BVD, IBR, liver fluke
  • Poor body condition
  • parturition- immune
  • effluent on pasture
  • Magnesium oxide supplement
  • post surgery

Syndromes:
acute: enteritis/dysentery, bacteraemia, pyrexia
Peracute: septicaemia and death
Chronic: Diarrhoea ±dysentery, weight loss, inappetence
Carrier: Asymptomatic
Sporadic: Mild diarrhoea
Abortions Dublin and brandenburg;
Calves: septicemia, meningitis, enteritis/dysentery

CS adults: severity varies

  • Sudden & severe drop in milk
  • Dull, loss of appetite
  • Profuse, foul-smelling, watery diarrhoea –shreds of mucosa and fibrin casts
  • elevated temperature
  • Dehydration, weight loss and death

CS calves: 2-6wks

  • Fever, dull, loss of appetite
  • Fever
  • Brown/grey pasty scour, foul-smelling with blood, mucus, sloughed mucosa
  • Dehydration, weight loss, weak, gaunt
  • Septicaemia/bacteraemial->pneumonia, meningitis and arthritis

DX:

  • faecal swabs (intermittent shedding)
  • PM: haemorrhagic enteritis, pseudomembranes
  • swab intestine and GB (bacterial culture)
  • Sample liver, spleen, lungs, mesenteric lymph nodes and intestines (for culture & histopathology)

TX:

  • Broad spec: trimethoprim-sulphonamide, ceftiofur, oxytetracycline (prognosis reasonable if started early)
  • Fluid therapy –orally or hypertonic saline (2-2.5 litre7% NaCl) i/v followed by water via stomach tube (20-40 litres)
  • NSAIDs (e.g. flunixin)

Prevent:

  • Isolate
  • Reduce stocking rate
  • Prevent contamination of feed/water
  • Spell pastures for 4-5 weeks after spreading effluent
  • Closed herd policy
  • Vaccination (Bovilis S®), - outbreak likely, 8 and 3 weeks prior to calving (colostral ab)
  • Rodent & bird contro
  • Take care with MgO supplementation
  • Careful sourcing of calves; closed herd policy; avoiding sale yards; quarantining introduced stock
  • Strict hygiene –pens, utensils, staff
  • Effective colostrum management
  • ‘all-in all-out’ polic
  • Vaccination: passive antibody protection (cow)
  • calves at any age and boost 3-4 weeks later
35
Q

Johne’s disease
Pathogenesis
Clinical signs

A

Mycobacterium avium sbs paratuberculosis
Chronic granulomatous enteritis, Lymphangitis of mesenteric lymphatics, enlargement of mesenteric lymph nodes (involves all organs) presenting after 4 years, 1% mort

Transmission: 
Horizontal (before 6 months of age-resistance to infection increases with age) 
- faecal-oral route 
- colostrum & milk from infected cows 
- water borne 
- semen, faeces, urine, respiratory 

Vertical (in utero –transplacental)

  1. resistance
  2. intermittent shedding
  3. clinical disease, shedding high amounts

Presenting signs: clinical disease

  • Production losses and lower milk production
  • Chronic weight loss, normal appetite
  • Diarrhoea intermittent then continuous hose-pipe
  • no fever or inappetence, normal rumen activity
  • Malabsorption and protein-losing enteropathy- submandibular, ±brisket oedema
  • Coat depigmentation
Clinical signs: 
Stage 1: silent infection
Stage 2: subclinical infection 
Stage 3: clinical disease → 4-6 years
•Stage 4: advanced clinical disease
- ‘hose-pipe’ diarrhoea 
- submandibular oedema (protein-losing enteropathy) 
- smildly anaemic 
- death 
PM: corrugated intestinal mucosa 
- acid fast actinobacilli
36
Q

Detection and prevention of Johne’s disease

A

PCR good
Serology: antibodies in progressed
bacteria in serologically positive
ELISA: screening, specific, not sensitive

Individual:
Check test: 50 cows
Sample test: 200-300
HEC: herd environmental

Control:

  • isolate and destroy
  • reduce faecal contamination on pastures
  • Calf program: calf removed from cow within 12hr, reduced faecal matter, place on pastures with no previous exposure (1yo)
JBAS: johne's beef accreditation score 
score 0-1 no plan
score 2-6 some management 
score 7, 8 actively managing 
Livestock production accreditation- needs bioesc plan

vaccinate in heavily infected herds

37
Q

Yersinia

A

Yersinia pseudotuberculosis, enterolitica
mostly yearlings in good condition
gut inhabitant (+ faecal result not indicative)
Stress, bad weather
Birds, rats reserviour
selenium and copper deficiency

Clinical signs:

  • green, brown chronic diarrhea
  • anorexia
  • dehydration
  • fever
  • poor growth, wasting

Diagnosis:

  • faecal culture
  • neutrophilia with left shift
  • hypoproteinaemia and anaemia
  • PM: ulcerative enterocolitis, villous atrophy, microabscessation

TX:

  • Trimethroprim-sulphonamide, oxytetracylcline
  • oral fluids
  • fair PX
38
Q

BVDV

infection

A

Type 1 in Aus
spread through nasopharyngeal, semen, urine but not faeces

in utero:
<40 EED
d40-120 PI
~d150 abort and foetal abnormalities

naive animals: transient
- diarrhea, immunosuppression, inappetant, reproductive loss
-