Farm animal neonatal disease Flashcards
Role - colostrum
- IMMUNE: primary protection vs neonatal septicaemia and joint/ navel ill, protect vs enteropathogens, protect against enzootic pneumonia
- NUTRITION: first feed, with additional vitamins and trace elements
What % calves die?
8.8% (i.e. 176,000 calves)
Main causes death in calves - 3
- diarrhoea
- pneumonia
- FPT
Phsyiology - colostrum
4-6 wks before calving there is Ig transfer into udder, IgG1 is actively transferred to colostrum, following ingestion of colostrum by calf, Ig is absorbed by epithelial cells of SI and passes via lymphatics to peripheral blood circulation
Outline the systemic and local protection that colostrum offers
- SYSTEMIC: with IgG1 and IgM
- LOCAL protection of GIT: re-secretion of IgG1 into GIT lumen, passage of IgA in colostrum/ milk through gut lumen
How much IgG1 is needed?
- 5g/L in plasma (protection)
- 10g/L in plasma (no dz)
What is the dz triad?
- immunity
- agents
- environment
How much blood is in the average mammal?
8% BWt
What factors influence uptake?
- first milking: rapid decrease after each milking
- milk yield: only 29% holsteins have 100g Ig in 2 L of colostrum
- dairy vs beef
- pre-calving milking or leaking of milk
- short dry period
- premature calving/ abortion
- heifers vs cows (heifers have reduced milk yield thus increased concentration but pathogens that Ab covers are less varied as less exposure d/t younger age)
What are the 3Qs?
Regards colostrum: quality, quantity, quick
Are beef and sheep young able to suckle to get sufficient colostrum?
usually ok because need a small volue of concentrated colostrum
Are dairy young able to suckle to get sufficient colostrum?
often rely on suckling but probably not best:-
- 2L at first feed traditional
- 3-4L for 45kg calf from holstein dam more effective
What 3 main factors affect the volume of colostrum a calf sucks?
- CALF (weak, acidosis, dystocia, mouth problem e.g. tongues of belgian blues being double mm)
- UDDER (sore teats, teat alignment, teat shape/size, dropped udder)
- MOTHER: poor mothering, heifers, disturbance/ stress, overcrowing of calving area, c-section, milk fever/ downer cow, slippery floors
How do you ensure a calf gets enough colostrum?
- assisted suckling (20-30 mins continuous suckling to ingest 2L)
- bottle and teat and patience!
- oesophageal feeder 3-4L (Not a stomach tube!)
What does closure of gut wall depend on?
- presence of protein in GIT (negative feedback loop: presence of proteins causes gut wall closure)
- time after calving
What is one of the most important risk factors for hypogammaglobulinaemia?
delay in suckling
What determines colostrum quality?
- exposure of dams to pathogens
- vaccination (e.g. rotavirus): store colostrum and allow it to ferment, feed stored colostrum for several days (IgA)
How do you assess colostrum quality?
- IgG cut-off point of 50g/L
- Specific gravity (good if >1.048): use hygrometer, cave: temperature sensitive
- Brix refractometer: aim for > 22%
- thicker the better
How do you assess colostrum UPTAKE?
CALF SERUM:
- IgG of >10g/L
- gammaGT (200IU/L on day 1, 100IU/L on day 4)
- TP > 55g/L (some argue > 60g/L)
- Zinc sulplate test = ZST (>20g/L)
- Sodium sulphite >18g/L solution
What if colostrum managment fails?
- feed stored colostrum OR
- feed a commercial colostrum supplement
How long can colostrum be stored?
- 15 degrees = 24 hrs
- 4 degress = 7 days
- 20 degrees = 60 months +
How to thaw colostrum
thaw at room temperature so proteins and enzymes and immunoglobulins etc aren’t destroyed
How to store colostrum
- in 1 or 2 L aliquots
- collect from first milking only
- fermented colostrum is not suitable for first feed, but useful for IgA for rotavirus
What is ‘anaemia’?
Not a CS but a lack of erythrocytic haemoglobin
CS - anaemia
- pallor
- exercise intolerance
- weakness
- haemic murmur
- dependent oedema
- red urine (ddx haematuria)
- jaundice
- black faeces
- swollen udder
Which MM should you check?
- mouth
- eyes (conjunctiva and sclera)
- nose
- vulva
- FA MM are often pale in comparison with other spp
Clinical pathology - anaemia
- low PCV
- low Hg
- immature erythrocytes (smear)
- evidence of regenerative / absence
- jaundice
Normal PCV - cattle
24-46%
Normal PCV - sheep
27-45%
Normal PCV - swine
22-38%
What should you always interpret PCV in conjunction with?
TP as dehydration may raise the PCV
Name 3 types of anaemia
- Blood loss/ haemorrhagic anaemia = REGENERATIVE
- Erythrocyte destruction/ haemolytic anaemia = REGENERATIVE
- Inadequate erythrocyte production (BM) = NON-REGENERATIVE
Main cause - haemorrhagic anaemia - 3
- Enzootic haematuria
- Haemonchosis
- Fasciolosis
Other causes - haemorrhagic anaemia
- Enzootic haematuria
- Haemonchosis
- Fasciolosis
- CdVC syndrome
- ruptured uterine artery
- ruptured aorta
- lice, mites, ticks
- pyelonephritis
- abomasal ulcer
- intraluminal intestinal haemorrhage
- gastric ulceration in pigs
- proliferative haemorrhagic enteropathy in pigs (PIA)
Main causes - haemolytic anaemia
- leptospirosis
- Protozoa (Babesia, Eperythrozoon)
- Chronic copper poisoning
Other causes - haemolytic anaemia
- leptospirosis
- Protozoa (Babesia, Eperythrozoon)
- Chronic copper poisoning
- postparturient haemoglobinuria
- bacillary haemoglobinuria
- cold water ingestion
- Brassica poisoning
- drug induced
- blood transfusion
- autoimmune HA
Main causes - depressed erythrocyte production - 3
- deficiency of cobalt or copper
- fasciolosis
- anaemia of inflammatory dz
Other causes - depressed erythrocyte production
- deficiency of cobalt or copper
- fasciolosis
- anaemia of inflammatory dz
- iron deficiency
- acute bracken posioning (enzootic haematuria)
- lymphosarcoma
- chronic renal dz (amyloidosis, pyelonephritis)
- radiation damage
Tx - anaemia
- BLOOD TRANSFUSION: adult cow may need 5L of blood, first transfusion should be safe
- HAEMATINICS (support RBC synthesis) : Fe, Cu, vit B12, high protein, fresh foods
CS - enzootic haematuria
- haematuria with blood clots
- frequent urination
- thickened bladder that may or may not be palpable per rectum
- other signs of chronic progressive anaemia
- internal bleedings
Cause - enzootic haematuria
bracken fern is commonest cause of enzootic haematuria in cattle
Dx - enzootic haematuria
- bracken fern is commonest cause of enzootic haematuria in cattle
- pyelonephritis also causes haematuria but not necessarily anaemia
Causes - abomasal ulcer - 3
- sand
- DA
- stress
Dx - abomasal ulcer
- occult blood in faeces/ black stinking dung
- free air in abdomen
- abdominal pain
Describe Fe deficiency anaemia
- young animals (milk has low Fe)
- diet and injectables
- other micronutrients
Describe anaemia of inflammatory disease
- alterations in Fe metabolism
- depressed BM response
- shorter RBC lifespan
Outline chronic Cu poisoning - signalment
- spp and breed susceptibility variation
- sheep»_space; calves (moderately susceptible)» adult cattle
- Texels and suffolks»_space; Sc Blackface and merinos
What happens in chronic Cu poisoning?
Cu is stored and accumulated in liver –> some centrilobular necrosis occurs as liver Cu concentrations rise (750ppm) –> ultimately sudden release of Cu from liver into blood –> acute fatal syndrome develops.
- THUS chronic Cu poisoning is an acute dz following chronic absorption and accumulation of Cu
Sources - Cu
- DIET (main cause of chronic poisoning): concentrates, phytogenous (pasture), hepatogenous (liver damaged by PA)
- ACCIDENTAL OVERDOSAGE:more likely to cause acute poisoning
When are sheep most prone to Cu poisoning?
- when sheep are fed concentrate feeds
- particularly if fed for prolonged periods (milking ewes)
- particularly if no effort is made to counter Cu absorption (with Molybdenon)
What levels of Cu are normal / cause poisoning?
- levels 12ppm may be dangerous (depends on breed, length of time fed and presence of inhibitors). Many commercial sheep feeds exceed this. Cattle and pig feeds typically exceed this level by far.
CS - chronic Cu poisoning
- jaundice (the yellows, toxaemic jaundice)
- pallor
- haemoglobinuria
- depression
- death in 24-48 hr of haemolytic event
Clinical pathology - chronic Cu poisoning
- blood Cu elevated (but after release of Cu)
- liver Cu elevated (Blood can predict)
- as for other causes of acute haemolytic anaemia
- increased plasma AST (d/t liver damage)
Necropsy – chronic copper poisoning
- swollen yellow liver
- swollen ‘gunmetal’ kidneys
- jaundice everywhere
- take liver for Cu assay and histopath
Ddx - chronic Cu poisoning
- haemoglobinuria (bacillary and postparturient, rape and kale poisoning, leptospirosis)
- jaundice (fascioliasis, lupinosis)
- anaemia (haemonchosis)
Tx - chronic Cu poisoning - 4
- ammonium tetrathiomolybdate (ATM), give 2.7mg/kg at 2-3 d intervals for 3-6 tx
- ammonium molybdate 100mg + sodium sulphate 1g ORAL daily
- sodium calcium edetate 70mg/kg IV for 2 d
- Somnulose 10ml IV (euthanasia?)
Prevention - chronic Cu poisoning
keep dietary Cu in normal range
