Calf MOD Flashcards
What is navel ill?
Infection via navel or oro-respiratory route
May involve umbilical arteries, veins, urachus
Swollen navel
May result in peritonitis, septicaemia, polyarthritis (joint-ill)
What are some risk factors for navel ill?
Pathogen load (hygiene at calving) Was iodine used on navel? Immune status of calf (colostrum intake)
How do you diagnose navel ill?
Swollen and hard navel
Abdominal palpation to see if umbilical vessels are abcessed
Probe
Ultrasound (follow umbilical artery to bladder towards aorta, and vein to liver)
How do you treat navel ill?
Antibiotics
Drainage
Surgery (remove infected umbilical arteries and urachus. If veins affected- poor prognosis)
What is joint ill?
Septic arthritis Usually a sequel to navel I'll Risk factors: hygiene at calving, FPT (failure of passive transfer) Single or multiple joints Poor prognosis
How do you treat joint ill?
Long course of antibiotics
Joint lavage (hard to do as needles plug up with fibrin)
Arthrotomy (opening a joint) and flush joint
Antibiotic impregnated beads after flushing or arthrotomy (amoxicillin, clindamycin)
What is the difference between bacteraemia and septicaemia?
Bacteraemia= bacteria in blood, secondary to mucosal damage eg rumen acidosis, mastitis
Septicaemia= bacteria multiplying in blood. Concurrent endotoxaemia, fatal
What is the primary cause of septicaemia in calves?
Lack of colostral antibody
When do calves usually get septicaemia?
From 0-5 days old (failure of passive transfer)
Few cases at days 5-14 (decline in IgM, allows bacteria to spread from navel to blood circulation)
What are the main antibodies in colostrum?
IgG and IgM
Decline in IgM after 5 days
What are the clinical signs of septicaemia?
Collapsed
Shock (endotoxaemia)
Very congested conjunctiva (petechiae, DIC)
CNS signs sometimes
What are the risk factors for septicaemia?
Pathogen load (hygiene at calving and in calf-rearing area) Immune status (colostrum intake)
How do you perform a cerebro-spinal fluid tap?
What would you see in an abnormal sample?
Put calf in sitting dog position
Lumbosacral junction, at level of ilium (‘thumb notch’)
2” 19G needle
Abnormal= high protein, ‘froth’, due to ‘shot’ blood-brain barrier
How do you treat septicaemia?
Very rarely successful Antibiotics NSAIDS (flunixin) Corticosteroid 1mg/kg Fluid therapy Supportive nursing, warmth, feeding etc
Describe calf diphtheria including treatment
Fusiformis necrophorum
Oral lesions (sore mouth, salivation and foul smell, ulcerative lesions)
Caused by poor hygiene eg dirty buckets
Tx= penicillin
Give the cause of abdominal swelling in each case:
Left-sided swelling
Right-sided swelling
Left-sided swelling: bloat, free gas in rumen
Right-sided swelling: ‘abdominal catastrophe’ eg volvulus, torsion, laparotomy indicated, very serious
What is atresi coli?
Gradual distension of colon over first few days of life, due to part of bowel being blocked off from rectum, unable to defecate
Euthanasia
How do you treat calf bloat?
Relieve distension with tube/trocar (‘red devil’ trocar used to release gases)
Correct underlying risk factors
What is ETEC diarrhoea caused by?
When do calves get it?
E. coli
Less than 5 days old
If a calf has diarrhoea and is over 6 days old, what are the most likely causes?
Rotavirus, coronavirus, crypto
Give the causes of metabolic acidosis
Loss of bicarbonate
Addition of acid and neutralisation of bicarbonate
Dilution of bicarbonate (inappropriate fluid therapy)
Why must there be sufficient surfactant in the lungs at birth?
So the lungs can inflate to take the calfs first breath
What is the stimulus for breathing at birth?
Change from placental to lung oxygenation
Stimulus for breathing is build up of CO2 (respiratory acidosis)
Give two causes of foetal hypoxia
Compression of umbilical cord
Premature placental separation
How does dystocia lead to acidaemia and hypoxaemia?
Dystocia -> hypoxia (compression of umbilical cord or premature placental separation) -> lactic acid production -> metabolic acidosis -> severe respiratory acidosis -> acidaemia and hypoxaemia
How long should it take for a newborn calf to get into sternal recumbency?
Less than 5 minutes
Over 9= increased risk of death
What is in colostrum?
High energy, protein, fats, vitamins
IgG, IgA, IgM are main immunoglobulins
Growth factors eg insulin, IGF-1, IGF-2, GH
Large number of inflammatory cells
When do colostral antibodies run out once inside the calf?
5-10 days old
What percentage of calves do not get enough colostrum?
30-50%
Why might a calf not get enough colostral antibodies?
Failure to suck eg poor teat conformation (too big)
Mothering ability of cow
High genetic merit dairy cows have poor quality colostrum
Weak (acidotic) calves don’t suck enough and don’t absorb antibodies from colostrum
Should have colostrum within 6 hours of birth
Give some factors that affect quality and quantity of colostrum
When colostrum is collected (decreased in antibodies over time) Breed of cow (dairy vs beef) Parity? Pre-partum nutrition Length of dry period (
Explain the ‘Teflon effect’
Antibodies from colostrum (IgA and IgG1)are absorbed from the gut into the bloodstream, then are re-secreted into the gut for 5 days
How can you assess passive transfer of maternal antibodies?
Measure serum immunoglobulins
- Refractometer: TP should be >55g/l
- ZST (zinc sulphate turbidity): over 20 units
- SST (serum separated tube): over 20g/l
- ‘Nasal stick test’ measures IgG