Phosphorus is a vital mineral that is required by the animal body.It plays a key metabolic role and has more physiological functions than any other mineral. These functions involve major metabolic processes such as: tissue and bone development,development and maintenance of skeletal tissue,maintenance of osmotic pressure and acid base balance,energy utilization and transfer,Protein synthesis, transport of fatty acid and amino acid exchange. Phosphorus compounds are involved, directly or indirectly, in all major physiological functions and therefore play part in or rather are responsible for intestinal absorption, glycolysis and direct oxidation of carbohydrates, renal excretion, transport of lipids, exchange of amino acids, etc. Phosphorus is also a component of a large number of coenzymes.


Phosphorus is one of the most important minerals in animal nutrition. It is the second most abundant element in an animal’s body after calcium, with 80% of phosphorus found in the bones and teeth, with the remainder located in the body fluids and soft tissue.

Phosphorus deficiency is a disease especially of domesticated cattle caused by inadequate feed intake, intake of dietary phosphorus or inadequate phosphorus content in the ration over an extended time. It is a disease that is widespread throughout the world and country and is due to a low phosphorus in the soil in arid regions which is of course lower in content in some areas than others. It is a syndrome that is more common in grazing species and the mineral is most likely to be deficient mostly in beef cattle. It also affects small stock too.


Primary: – caused by deficiency of phosphorus in soil hence in forage.

Secondary: – caused by poor absorption of phosphorus from the gut or loss as a result of gut problems caused by internal parasites or inflammation.

Note – primary and secondary hypophosphatemia in this country are usually combined.

The disease can manifest in different ways as it is needed for many functions in the body for various uses. It can come as the common

  • Hypophosphatemia- these is the earliest stage where by blood levels of inorganic phosphate are low or marginal. The calcium: Phosphorus ratio is lower than it should be (2:1) therefore animal shows signs of inappetence, stiffness as well as low milk production.
  • Rickets and Osteomalacia (bone softening) may occur in prolonged deficiency with bones becoming fragile and some even fracturing like ribs.


  • A Vitamin D deficiency or an excess in dietary calcium will reduce the absorption of phosphorus. The most critical need for phosphorus is the last trimester of pregnancy (2-3 months pre-calving) and the period immediately prior to breeding season.
  • History of very limited superphosphate application on soils naturally deficient in phosphorus.
  • Lactating females and young growing animals are more prone as the mineral is deposited in milk production and if it is deficient in the mother, the young will have a deficit and stunted growth, rickets as well as soft bones may occur.



  • A common symptom of phosphorus deficiency is often seen as an abnormal habit of eating or chewing foreign substances such as dirt or wood which is also known as pica which predisposes them to botulism.

Phosphorus deficiency can result in

  1. low conception rates,
  2. Incoordination in movement
  3. reduced feed intake due to in appetence,
  4. Lameness
  5. poor feed efficiency,
  6. Unthriftness
  7. lower growth rate in young animals,
  8. Stiffness
  9. reduced milk production,
  10. Scouring
  11. reproductive failures,
  12.  Anorexia
  13. Softening of bones that can result in fractures
  14. Recumbency in cattle.
  15. Skeletal abnormalities such as rickets.
  16. Animals appear weak



  • Visual symptoms such as Pica (eating bones and other rubbish), poor growth, soft bones and fractures, infertility, post calving red water are diagnostic features/ abnormalities for the disease.
  • Pasture samples, soil samples and blood samples from affected animals can also be useful, as well as a clinical response-to-treatment trial.


Supplement regularly especially livestock in their trimester of calving.

Most effectively treated by providing sufficient amounts of feed with adequate phosphorus content.

Mineral licks to correct mineral imbalances such as:

  • Di-calcium phosphate
  • Monosodium phosphate
  • Report the case to the veterinary officer who will give injections of phosphamine.

In animals grazing on phosphorus-deficient soils, depletion may be prevented by fertilizing the soils with phosphorus or by supplementing feeds or the water supply with phosphate salts.