Hybrid varieties of rye could provide an excellent new source of nutrition for pig producers, especially in light-land areas
New, higher-yielding hybrids now in UK trials could help rye complement wheat, barley and oats in animal feed, improving gross margins and bringing major rotational benefits as a result.
With all the evidence suggesting an equivalent nutritional feed value compared to wheat or barley, the crop, which is currently only grown for the limited rye-bread market and as a biogas feedstock, could replace other grains in pig and other livestock rations.
According to Denmark-based KWS agronomist Jacob Nymand (pictured above), hybrid rye is already poised to become the main grain source for cattle and pigs in his country, and there’s no reason why it shouldn’t become a major feed source in the UK as well.
“Across 22 trials in Denmark on a range of soils between 2009 and 2012, hybrid rye produced mean yields that were up to 17% ahead of wheat and triticale, and 22% ahead of winter barley,” he says. “Furthermore, with advances being seen from new plant breeding material every year, I’d expect the yield gap between other cereals and hybrid rye to continue to rise to around 33% by 2018.
“Alongside these significant yield improvements, KWS has also introduced Pollen Plus Technology, a combination of genes bred into its newest hybrids to boost pollen supply during the flowering period, effectively negating any serious ergot threat. As a result, the animal feed market has taken off.”
Feeding value
While rye has a lower feeding value than wheat (4-5% less MJ/100kg of grain) and a 1-2% lower protein content, its higher yield generates more feed value/ha on light soils than wheat. With no historic feed price for rye in Denmark, the industry equated an equilibrium price for the crop based on its ability to finish pigs at the same rate as wheat based on 40% rye in the diet.
Assuming wheat at £133/t, and taking into account rye’s slightly lower feed value, the equivalent price for rye is about £120/t. However, with light land rye costing about £46/t less to grow than wheat, farmers quickly realised the potential and the feed industry also took note.
“While rye has a similar fibre content to other grain, the fibres are very slow to breakdown. So, in the same way that rye bread makes us feel fuller for longer, the same applies to pigs,” Mr Nymand says. “While this is a potential negative in pig production, using a wet feed system where the rye is fermented enables intakes of 20-40% in the ration and has the benefit of leaner meat, improving marketability.”
The Danes are currently ad-lib feeding slaughter pigs at rates of up to 40% rye. While daily liveweight gains are a little lower than normal, the meat is leaner and secures a higher price.
As a result, about 150,000ha of rye is now grown for both human and animal feed purposes in Denmark, and the area is expected to grow further – largely at the expense of second wheats. And winter barley and triticale are now rarely used in Danish compound feeds.
UK benefits
According to KWS’ UK sales manager, Bill Lankford, UK farmers who could benefit most from hybrid rye are those on light land and where second wheats are failing to deliver.
“There’s an immediate local market for rye for pigs, given that many outdoor units are also on lighter, less-fertile ground, across large areas of East Anglia, the south coast and Yorkshire,” he says. “And with hybrid varieties yielding 0.5t/ha more than the best feed wheats in our trials, and yet costing less to grow, there are significant advantages to be gained.
“We have seen how our Continental colleagues have developed the grain market for a crop that is ideally suited to difficult growing conditions, and recognise that the time might be right in the UK as well.”
KWS claims that while plant breeding advances are generating another 0.3-0.5t/ha to UK wheat yield potential every year, the best new hybrid rye varieties in East and Northern Europe are accelerating yields by about 2% annually and this could benefit growers here.
Mr Lankford says that in trials during the past two seasons where the best wheats and hybrid ryes were grown alongside each other, rye typically outyielded wheat.
“As a second cereal in the Yorkshire Wolds and Dorset, we’ve seen it outcompete our best wheat by 1.5t/ha, and in a first-cereal situation in Cambridgeshire hybrid rye has achieved 12.2t/ha in trials.
“While there’s no market price for rye at present, assuming it’s traded at a 10% discount to wheat – as in other European countries – and a base feed wheat price of £122/t, rye yielding 5% more than wheat would produce an output that is just £40/ha adrift.
“Factor in reduced fertiliser, herbicide and fungicide costs compared to a winter wheat, and even with a higher seed price, the crop is still £70/ha cheaper to grow, producing a higher gross margin as a result. This makes hybrid rye a very exciting prospect and one that the industry ought to re-examine.”
Other advantages
Jacob Nymand says that the Danes are also benefiting in other ways from the adoption of hybrid rye.
“A number are using its straw for fuel and, with a 2t/ha higher straw yield than wheat, they’re gaining £30-50/ha more from rye. Hybrid rye requires 30% less water than other cereals, so is extremely drought tolerant. And being deeper rooted to 1.5m, it’s better able to utilise nitrogen reserves; with fertiliser quotas imposed on Danish farmers this is a major plus point.”
Typical N use in Denmark is 130-150kg/ha in three applications, and trials suggest that the crop is able to utilise about 122kg/ha of this N in straw and grain, whereas wheat in comparison uses closer to one third of all applied N.
While growth regulation is important, fungicide use is much reduced. With an excellent tillering ability, rye physically smothers grass weeds such as blackgrass; combine this with an allelopathic effect, where its roots produce chemicals that hinder the development of other plants, and herbicide savings are likely as well.
UK trials have also shown that rye out-competes blackgrass in the autumn and that any seed that’s produced is less viable. While rye is no silver bullet, it can be another tool in the armoury to help overcome blackgrass problems.
KWS expects the area of hybrid rye to grow again this autumn, with varieties such as KWS Progas and KWS Magnifico taking the lion’s share.
“We are keen to develop links with those in the industry, particularly the animal feed sector and with livestock farmers to explore the potential further,” Mr Lankford says.