Injecting newborn piglets with iron may be a routine procedure on most indoor units but, in outdoor herds, it is often perceived that enough iron is obtained from the soil.

Outdoor sows are now more prolific, producing larger litters. These piglets also have a higher growth potential, which means there is more blood to manufacture – of which iron is an important constituent. It is thought piglets need about 10mg of iron a day for maintenance and growth, whereas sows’ milk only provides 1mg iron/litre.

A trial showed that supplementary iron could boost weaning weights significantly on outdoor units: weights were increased by 0.6kg in some months, with an average improvement of 0.26kg.

The trial involved splitting an 1,800-sow herd in two, so half the herd’s piglets received 200mg of elemental iron within 48 hours of birth. Piglets were weighed at weaning. Results included:

• Increased weaning weights by 0.26kg
• Reduced days to finish
• Return on investment of 10:1.

Producers should discuss with their veterinarian before providing additional iron to piglets as, even when soils have been tested for iron content, it can be difficult to interpret the information accurately, as iron can be bound up with different elements.