Trace element deficiencies Flashcards
Name 3 macro elements/minerals
Ca, Mg, P
Name some micro minerals
Co, Cu, Se/Vit E, I, Fe, Mn, Zn
What are trace elements/TEs/micrnutrients/microminerals?
elements essential for normal function (livestock). they depend on soil and plants for this.
Which TEs are limiting in temperate grassland?
Cobalt, selenium/vit E, copper, iodine
How can TE deficiency occur?
PRIMARY = soil/plant deficiency (Co, Se, I, Cu)
SECONDARY = lack of absorption in animal (Cu) Cu binds to Mo, S and Fe in rumen.
Local knowledge and experience is important!
Remember there is variation between individual animals as to their susceptibility.
Outline TE deficiency progression
Depletion –> deficiency –> dysfunction –> disorder
What factors can affect mineral levels? 8
variation in the proportion available animal ability to absorb varies contamination with soil seasonal changes selective grazing uneven distribution in plant and pasture disease in animal
Why is Co important?
essential component of Vit B12 which is part of a co-enzyme involved in the propionate –> glucose pathway. Deficiency thus leads to a shortage of glucose –> poor thrift. Rumen microbes incorporate Co into Vitamin B12
Clinical signs of Co deficiency? What is it often associated with?
Sheep most susceptible
Non-specifici signs, usually seen as poor thrift in weaned lambs, lethargy, poor growth rates, poor appetite, poor BCS, pale MM/anaemia in late disease, eye discharges and epiphora (cheek staining).
Often associated with concurrent parasitism and/or under-nutrition
How do you diagnose Co deficiency? 5
Vit B12 assay on blood samples (compare with reference values)
URINE (methylmalonic acid/MMA >5.0 micromol/l is abnormal)
LIVER SAMPLE - look at vit B12 DM content per kg
SUPPLEMENTATION TRIAL - feed Co supplement over 8-10 weeks and see if significant difference in weight gain in lambs compared with control
PCR - low indicates Co deficiency but non-specific
What might you find on PME with Co deficiency?
non-specific, emaciation, bone marrow hypoplasia, liver enlarged in severe cases
Treatment of Co deficiency?
Combine vit B12 injection with cobalt sulphate oral drench
Monthly drenching with Co (sometimes in anthelmintic drenches)
Cobalt oxide boluses
Why are Se/Vit E important? What happens in deficiency?
help protect cells as they are cellular antioxidants which protect against free radicals.
Deficiency –> membrane damage, tissue necrosis. Skeletal, cardiac and respiratory muscle and RBC susceptible.
What are clinical features of Se/Vit E deficiency?
Also called white muscle disease, stiff lamb disease, nutritional muscular dystrophy.
No real species or season predilection.
Clinical disease may be obvious
Sub-clinical disease is more subtle
Clinical signs of Se/Vit E deficiency?
white muscle disease that is congenital causing stillbirths and neonatal deaths or more usually at 2-6 weeks with a sudden onset of stiffness), lambs are bright but appear in pain and have lowered head carriage, deteriorate, recumbent, painful and swollen muscles, can be associated with recent stress.
