Piglet anaemia

Anaemia causes ill thrift (wasting) in piglets. Anaemic piglets look pale and accumulate fluid around the throat, brisket and internal body spaces.

Scouring (diarrhoea) is common, and resistance to other conditions and diseases is weaker. Anaemia is responsible for about 10% of pre-weaning deaths in untreated litters.

Cause

A shortage of iron.

Description

In piglets, anaemia is caused by low iron levels in their haemoglobin, the part of blood that transports oxygen through the body.

Until weaning, newborns lack enough iron to maintain satisfactory blood levels of haemoglobin, as sows' milk provides only tiny amounts of iron. Reared under natural conditions, piglets may obtain enough iron from soil, but as they are now generally reared indoors on concrete, metal or wooden floors, they need iron supplements.

Navel bleeding can also cause anaemia through blood loss. Navel bleeding can be inherited, or linked with vitamin-K deficiency, and sawdust or shavings from preservative-treated wood.

Faster growing piglets require more iron to maintain the same level of blood haemoglobin than slower growers. Normal supplement doses will provide enough. Also, earlier weaning will reduce the amount of iron supplements that you need to give. Weaning piglets at less than 21 days requires a high standard of management and nutrition to prevent piglet mortality and ill thrift.

Affected animals

  • pigs

Symptoms

  • Paleness (don't use for diagnosis as it can be misleading).
  • Accumulate fluid around the throat, brisket and internal body spaces.
  • Likely to scour (diarrhoea).
  • Susceptible to other conditions and diseases.

Impacts

Causes about 10% of pre-weaning deaths in untreated litters.

Risk period

Before weaning (once weaned, pigs should get enough iron from their diets).

Monitoring and action

  • Examine unclotted blood samples.
  • Examine smears at post-mortem.
  • Don't diagnose by apparent paleness as can be misleading.
  • Supplement with iron.

Control

Supplement with extra iron by injections (most common), dosages by mouth or by other methods.

Injecting

Inject with iron dextran, iron galactan or other iron compounds.

  • Give injection before piglets are 72 hours old.
  • Inject into the muscle or under the skin. Always follow the manufacturer's instructions.
  • Sterilise needles and syringes before use and clean the injection site.
  • Avoid excessive leakage from the injection site by using a suitable gauge of hypodermic needle.
  • Frequent bruising occurs at the injection site.
  • Injections in the leg can cause lameness, increasing the likelihood of being inadvertently overlaid by the sow.
  • Iron compounds can cause staining of the muscle at the injection site that do not properly cure and are difficult to detect. Frequently they are only detected by consumers, lowering the image of a good quality product.
  • Occasional infections or abscesses may develop at the injection site.
  • Inject in the neck behind the ear rather than in the leg to lessen lameness, staining and infections.

How to inject into the neck

  • Turn the pig's head to one side to stretch the skin and muscle at the injection site. This helps prevent the dose leaking.
  • After injecting, place your thumb over the site and allow the pig's neck to straighten.

OR

  • Hold the piglet between the left elbow and body.
  • Use the left hand to pull the piglets right ear forward, exposing and stretching the skin of the neck.
  • Use the needle to push the skin forward, and then push into the muscle. Pushing the skin forward before injecting helps prevent dose leakage.
  • Withdrawn the needle and release the ear at the same time.

The most suitable needles to use are 18 gauge and 12mm, or 20 gauge for thinner liquids.

Subcutaneous (under the skin) injections can be given over the rib cage.

Injections can only be carried out by competent stockpersons or staff under their direct supervision. Refer to the latest edition of the Model code of Practice for the Welfare of Animals: Pigs.

Oral dosing

Oral doses can avoid staining, lameness and infections caused by injecting but are more costly. They are also unreliable if piglets are scouring as absorption through the gut is less efficient.

How to dose with organic iron prepared with iron galactan:

  • give before piglets are 18 hours old (iron galactan is only absorbed from the gut very early in life)
  • give the full recommended dose
  • give a second dose if the first is regurgitated
  • use an alternative preparation if more than 18 hours old.

Sometimes anaemia can develop even though the piglets have been dosed with iron galactan. The common reasons are ill-timing, incorrect dosing technique or early scouring. Some reports say that oral dosing with iron can itself cause scouring, by enhancing bacterial growth in the gut.

Cheaper inorganic iron (e.g. ferrous sulphate) may be given orally, but amounts that can be absorbed daily are limited, so repeated dosing is needed.

Other methods

These methods may be useful backups but individual dosing is better because you can be sure all piglets get iron supplements.

  • Sprinkle iron compounds and/or uncontaminated soil in farrowing pens.
  • Provide creep feed with a high-iron content.
  • Raise iron levels by piglets licking bare steel fittings in farrowing pens, and from sow udders coated with iron compounds.
  • Raise iron levels in lactating sow diets so that litters receive more iron, sourced not from the sow's milk but her dung.

Further information