## FEED CONVERSION RATIO'S: WHAT DO YOU NEED TO KNOW?

As an industry we are obsessed with figures: Pigs weaned per sow per year, Replacement Rates, Farrowing Rates, Mortality, Average Daily Gain (ADG) etc. But the most financially important of these figures, if you finish your pigs, is Feed Conversion Ratio (FCR).

FCR is calculated by dividing the kg of feed eaten daily, by the kg of live weight gained daily. For example, if a pig ate 1kg of feed a day and put on 0.5kg in weight his FCR = 2. In my head I directly translate the FCR number as the kg of feed the pig would need to eat to gain 1kg in weight, therefore the lower the FCR the better!

The thing with FCR is that a little change in the number can make a big difference. For example, if your finishing period (40kg – 110kg) FCR goes up from 2.8 to 2.9, it doesn’t seem very significant. But if you finish 15,000 pigs annually that is an extra 105 tonnes of feed a year, if we take a rough cost of finisher feed as £175 per tonne that’s £18,375 a year extra that you have to spend!

### A simple equation or complex balance?

Growing takes energy, and that energy comes from feed.

• ADG = Energy Intake – Energy for bodily functions – Energy for movement

So, to improve growth we can either increase feed intake, which is expensive, or we can reduce the energy that pigs are wasting elsewhere hence improving FCR. Now obviously we can’t change their basic bodily functions and we don’t want to restrict their movement, but there are some areas we can target:

• Correct Temperature. If a pig’s environment is too cold, it will use energy to keep itself warm. For every degree below its thermo-neutral zone a growing pig will lose 12g of growth per day. Set the correct temperature, or provide kennelling, curtains and extra bedding if naturally ventilated, to ensure the pig isn’t wasting energy keeping itself warm.
• Decrease unwanted movement. We want to pigs to express natural behaviour, mobilise and play, but we do not want them to fight or ride. To reduce these things we can split sex, keep pigs in constant groups from weaning, or consider using Improvac.
• Keep them healthy! Fighting disease is very energy consuming so keep your pigs as healthy as possible via vaccination, good management, good housing and good biosecurity.
• Appropriate feed rations. Always feed the correct diet so pigs are absorbing the optimal nutrition from what they eat.

True FCR can only be changed by altering pig management and nutrition, but most people calculate FCR based on feed delivered to a farm, not feed actually eaten. This means some people have a higher FCR just through feed wastage. Ensure all feed delivered to your farm actually reaches the pigs by keeping feed bins, augurs, pipes and feeders in good condition to avoid any wastages. A little waste each day can add up to an awful lot!

For further information please contact Zoetis UK Limited, Walton Oaks, Dorking Road, Tadworth, Surrey KT20 7NS. www.zoetis.co.uk Customer Support: 0845 300 8034. Use medicines responsibly (www.noah.co.uk/responsible). Date of preparation: August 2017. AH607/17