Trace Minerals Flashcards
What are the trace minerals?
- Iron
- Copper
- Zinc
- Selenium
- Cobalt
- Molybdenum
- Iodine
- Manganese
What is the major function of iron in the body?
Haemoglobin production
How is iron stored in the body?
- Ferritin - spleen, liver, kidney and bone marrow
2. Haemosiderin
Where do animals get iron from?
Diet - green leafy material, especially leguminous plants.
Is milk a good or bad source of iron?
BAD
What causes iron deficiency?
- Insufficient iron intake
- Poor dietary intake - rare
- Decreased absorption, e.g. chronic blood loss - parasites
- Decreased iron transport - e.g. decreased Cu or protein levels
How does iron deficiency present?
Microcytic hypochromic anaemia
Is iron deficiency common in lambs and calves? Why?
No, as management practices rarely allows them to be raised on an unsupplemented milk diet
How is iron deficiency diagnosed?
- Microcytic hypochromic anaemia
2. Decreased serum iron concentration - <110-150ug/dl
How do we treat iron deficiency?
Give oral ferrous sulphate or parenteral iron dextran
What causes iron toxicity?
Prolonged oral administration of iron
Is iron toxicity common in farm animals?
No
How does iron toxicity affect the body?
By generating excess oxygen-based free radicals, contributing to oxidative stress in cells -> lipid peroxidation
What are the clinical signs of iron toxicity?
- Trembling and convulsions
- Vocalisation
- Bruxism
- GIT disturbances and colic
- Reduced growth
- Concurrent potassium deficiency
What is the function of copper?
- Haemoglobin function
- Oxygen metabolism
- Protein formation
- Metalloenzymes
- Growth and metabolism
Where is copper stored?
In the liver
Are copper levels high in milk?
No!
What causes copper deficiency?
- Copper deficient soils
2. Molybdenum toxicity
How does copper deficiency affect the body?
Microcytic, hypochromic anaemia
What are the clinical signs of copper deficiency?
- Anaemia
- Poor growth
- Bone disorders
- Scouring and GIT disorders
- Depigmentation of hair and wool
- Brain stem and spinal cord disorders
What is enzootic ataxia or swayback?
A disorder seen in lambs due to copper deficiency causing lesions on the brain stem and spinal cod, causing muscular incoordination
How is copper deficiency diagnosed?
Low serum copper - <0.7ug/ml
What causes copper toxicity?
- Over ingestion of copper containing products
2. Ingestion of plants causing copper retention, e.g. sub-terraneal clover
What animals are most likely to be affected by copper toxicity?
Sheep - used in anthelmintic drenches
How does copper toxicity affect the body?
Accumulates over a chronic period, causing necrosis of the liver cells and acute intravascular haemolysis
How much copper needs to be ingested daily for chronic toxicity?
3.5mg/kg
What are the clinical signs of copper toxicity?
- Severe gastroenteritis
- Abdominal pain
- Inappetence and anorexia
- Diarrhoea and dehydration
- Shock
- Anaemia
- Dark brown urine
What congenital lesions are seen in copper toxic ewes?
- Absence of limbs
- Brachygnathia
How do we diagnose copper toxicity?
- Elevated copper levels in the liver
- Elevated liver enzymes - AST, LDH, ALT
- Anaemia
How do we treat copper toxicity?
- Ammonium molydenate - 50-500mg (reduces absorption and increased excretion)
- Sodium sulphate - 0.3-1g
- 20% lysine
- Symptomatic
- Zinc - increases excretion
- Vitamin C - reduced oxidative chages
What is the function of zinc?
- Enzyme systems
- Cell replication and differentiation
- Production, secretion and storage of many hormones
- Immunity
- Electrolyte balance
What is the dietary recommendation of zinc?
23-63mg/kg DM