Fodder beet is a high-energy crop giving 12MJ/kg dry matter (DM). It far outyields other forage alternatives. This is great for production and profit, but careful management is needed when adapting beef cattle to the crop.
New Zealand-based ruminant nutritionist, vet and fodder beet specialist Dr Jim Gibbs and SAC Consulting beef and sheep consultant Kirsten Williams set out systems for finishing cattle at 14-16 months or at 26-30 months, and for feeding suckler cows, at a webinar organised by Scotland’s Farm Advisory Service.
Two feeds in one
When cattle graze fodder beet they get two very different feeds. The leaf provides protein and minerals, especially calcium and phosphorus, while the bulb is an “energy bomb” of sugar and digestible fibre. In an agronomically well-managed crop, 25% of the plant’s DM is in the leaf. It’s essential to get a balance of bulb and leaf to maintain intake and, ultimately, profit.
While fodder beet is the primary diet, a small supplement of grass, silage, hay or, in the case of suckler cows, straw, is needed.
But restricting feeding of fodder beet or giving more or unrestricted supplement to avoid rumen acidosis or subclinical acidosis is not needed. In fact, it is counterproductive – feeding more supplement will reduce beet intake, slow overall intake and reduce profitability. A proper transition to a fodder beet diet will avoid acidosis.
14-16 month finishing system
Begin with 270kg liveweight animals at 175-200 days old
Step 2 – autumn
Graze on fodder beet and roughage supplement for 130-150 days until 400kg liveweight
Step 3 – mid-spring
Put out to pasture when grass is growing well and feed at maximum intake for 90 days to slaughter at 530kg liveweight
How to do it
Plan a two-week pre-transition to fodder beet:
- Train the youngstock to the electric fence
- Give them good-quality feed to help adapt their rumen for when they go on to fodder beet
- Vaccinate them against clostridial disease
- Check their trace element status (selenium, copper, cobalt and iodine). They will be growing fast so demand will be strong. Bolus or injection is best to meet any deficits.
Fodder beet offers a rapidly available and fermentable carbohydrate. Adapting cattle to eat it is similar to adapting them to a diet of cereal grains.
Teaching the animal to regulate its intake at a rate the rumen can handle is the most important part of the whole regime, more so within beef finishing systems than any other livestock class. Get transition wrong and you will see a very wide variation in liveweight gains at the end of the season.
- Start with 0.5kg DM fodder beet and 3-4kg roughage supplement an animal a day
- Don’t increase the fodder beet ration until you are confident the whole group is eating the bulb – this can take a week
- To help with transition, consider taking beet out to pasture and running over it with a tractor to smash it up
- Increase fodder beet by 0.5kg DM an animal every second day
- Keep increasing until they are leaving beet behind
- Youngstock are fussy, slower to learn and have a higher protein requirement than older cattle. They respond best to leafy, green palatable crops
- Once transition is complete, they should be on unrestricted fodder beet, and the supplement should be no more than 1kg DM an animal a day.
- Giving more than 1kg DM supplement will reduce beet input, daily liveweight gain (DLWG) and profit.
- Strip grazing grass is best. Avoid poor quality hay, silage or straw
26-30 month finishing system
Begin with 18-month-old 440kg-plus liveweight cattle
Step 2 – mid-autumn
Graze on fodder beet and roughage supplement for up to 100 days. Pasture is not needed in this system. Expect a daily liveweight gain (DLWG) of more than 1.3kg.
Step 3 – winter or early spring
Slaughter directly off the crop at target 550kg liveweight
How to do it
- Transition to allow the rumen to adjust:
- Start with 1-2kg DM fodder beet and 7kg roughage supplement (usually co-grazing) an animal a day
- Once the whole group is eating bulb, increase beet by up to 1kg DM an animal every second day
- Work up to unrestricted intake – this may take 14 days or more – with 2-3kg DM/day supplement
- If transition is poor, intake will be slow and DLWG affected
- As with younger stock, check trace element status and correct if needed, as demand will be strong
A peculiarity of fodder beet intake is that maximum intakes are only achieved when there are three days of the crop left behind on the ground. If you can’t see three days of beet the cattle haven’t got enough, and their allocation needs to be extended. If not, their intake – and your profitability – will fall.
- Leave 25% – or one in four beet – from the day before
- Leave 10% from the day before that
- Leave 5% from the day before that
Conversely, except in very wet weather, if you look behind you and see more than three days of beet, intakes are at their maximum and there is no benefit in allocating more.
Feeding fodder beet to suckler cows is a much easier and less aggressive system than for finishing cattle. They can be fed beet throughout their gestation and moved to grass or into housing before calving.
Cows are very good at getting beet out of the ground, so take this into account when calculating allocations. They will dependably eat their ration and routinely gain 0.5-1 in body condition score.
What they need
- 2.2% of their bodyweight, for example, a 650kg cow needs 12kg of beet and 2kg of supplement
- Choice of supplement is less important for sucklers – hay, straw, silage, or a mix
- Restricting supplement to very low levels is not such an issue as with finishing systems
- 12-13% protein is adequate and easily achieved on beet
Cows are less fussy than finishing cattle. But they can also eat themselves into a poor situation more easily, so are more prone to acidosis.
- Start with 1kg DM fodder beet and hold off increasing allocation until all the cows are eating it
- Allocate beet carefully and make sure there’s enough supplement
- Transitioning in lactation is a slower process. Expect cows to remain on early allocations for an extended period.
To allocate the crop you need to know the yield. To measure 5sq m of crop:
1. Measure 5m* along the row in a random sampling area, avoiding end riggs
2. Lift the whole plant (bulb and leaf) from either side of the measuring tape
3. Use a knife to separate leaf and bulb
4. Weigh leaf and bulb separately, including all brown, slimy leaves in the leaf measurement
5. Repeat over the field (five sampling areas of 5m x 1m = 25sq m)
*If row width is 50cm, measure 5m along the row; if it’s 45cm, measure 5.5m.
Example of how to calculate yield of fodder beet
|A||Total fresh weight of samples (FW)||262kg||158kg|
|B||Tonnes FW/ha – A x400 + 1000||104.8t/ha||63.2t/ha|
|C||Dry matter (DM)*||15%||10%|
|D||Tonnes DM/ha (B x C)||15.72||6.32|
|E||Tonnes DM yield (D bulb + D leaf)||22.04|
|*Dry matter of crops varies greatly. Testing is available at forage analysis laboratories|