Fonterra farmers should be familiar with FEI or Fat Evaluation Index. In 2018 the Fonterra Co-op established this index to encourage their farmers to produce milk with fat levels that are more suitable for processing into dairy products. Milk with a high FEI can reduce the quality of products that can be made.
How does grading work?
Fonterra farmers receive an FEI classification for each pick-up. It works on an A-D scale. (see chart)
A grade of A, B, C, or D will be provided to farmers daily and will reflect a 6-day rolling average. Milk that receives an FEI grade of C or D for three consecutive days will be retested to confirm the grade. Demerits will be only be applied if this second test results in a grade of C or D. This means there is plenty of time for you to take action and change the feeding regime to reduce your FEI.
Why all the fuss about PKE?
PKE is an important and convenient feed option for most farmers, especially in tough conditions. Unfortunately, PKE is the main driver for increased FEI. It has a high plant fat content ranging from 3-10%. This varies depending on origin, manufacturer, supplier, and shipment.
What else affects FEI? How can it be managed?
Track your FEI graph. If you are approaching a ‘B’, check how much PKE is being fed and consider what else is being offered.
- Think about the proportion of PKE in the diet i.e., if a cow is eating 3kg PKE in a 14kgDM diet, this is much higher than a cow in peak lactation eating 18kgDM/day. This generally goes hand in hand with the stage of lactation.
- a. Aim to keep PKE feeding at no more than 20% of total intake i.e., no more than 3kg in a 15kg diet.
- b. The general rule is no more than 3kg PKE/cow/day regardless – learn what level your farm, herd and feeding approach can allow.
- Consider alternative supplements instead of PKE for milking cows and allocate more PKE to dry cows.
- Think about the other supplements you are offering as feeding PKE with other feeds high in starch (maize) or sugar (molasses) can also increase FEI levels.
- Consider your transition onto crops. If done poorly the rumen flora don’t have time to adapt to the new feed resulting in a short-term increase in FEI.
- Going OAD can affect the FEI. Check FEI levels closely when switching to once a day (OAD) milking.
- Jersey cows naturally produce milk with higher fat content, so changes in dietary fat (PKE) can have more of an impact than in other breeds.
If you are having trouble managing your FEI, talk to your vet who can help you with some options to get things back on track.