Increasing feed efficiency and reducing costs are priorities for most pig businesses. However, with sights firmly set on boosting sow productivity and raising numbers weaned, Jane Jordan asks if compromising diet quality is a wise option when feeding your breeding herd
Today’s prolific dam lines have the capability to produce large litters, given the right management and correct feeding regime. But optimising efficiency in the long-term takes foresight and a clear understanding of the intricate relationship between body condition and productivity.
Independent feed specialist Alan Ford says significant improvements could be made to breeding herd performance if producers took a more long-term approach to sow nutrition. Providing good-quality diets should be the foundation of sow and gilt-feeding strategies, as relying on least-cost formulations, where nutritional values may fluctuate, can cause problems.
“There’s an enormous temptation to choose cheaper feed options, given the high price of raw materials,” he explains. “But short-term savings could have a considerable impact further down the line. Maintaining diet quality is the best way to sustain sow performance and the economics do stack up.
“Chasing low-cost ingredients may cut feed costs now, but it could end up costing you dear later on when productivity falters.”
With BPEX now urging every herd to ‘Breed +3′ more pigs per sow per year, sow nutrition warrants careful consideration.
Alan says breeding herds need to evaluate the potential losses associated with any fall in Farrowing Index (FI), litter performance or an increase in empty days, all common trends when sow nutrition is compromised. The cost of such losses will usually far exceed the investment that could have been made in a diet capable of sustaining performance.
Consider these simple calculations based on 330-sow breeding/finishing herd, with a FI of 2.25, producing 742 litters a year, weaning 10.5 pigs per litter. The loss of one farrowing a week could potentially cost the business up to £21,840 a year – assuming DAPP at £1.60 and the herd is producing 546 x 8kg pigs valued at £40 each.
If FI slips to 2.09, then 690 litters would be produced a year, a loss of 52 litters. If an 8kg piglet is worth £40 at weaning (DAPP at £1.60) then a litter is worth £420. If the piglets are worth £32.50 each (DAPP at £1.30), then a litter is valued at £341.25. This would, therefore, equate to a loss of between £17,745 and £21,840 a year, equivalent to a cost of between £2.45-3.01 for every pig sold. For the same number of bacon-weight pigs valued at £125, this amounts to a loss of £68,250.
The primary objective for a pig business should be to produce maximum output, and although a low-cost ingredient may seem sensible on paper, will it work in practice?
“Will sows have to eat more to satisfy their nutritional needs; can they achieve the intakes required to sustain productivity?” asks Alan. “These are key considerations and in most cases quality is preferable to quantity.”
More in, more out
As productivity increases, so will a sow’s nutritional requirements, which can create challenges when feeding highly prolific sows. The Stotfold Lactation Feeding Scale, developed in the mid 1990s, proved how sow productivity could be optimised by better nutrition management. As lactation progressed, rations increased exponentially to match milk production and piglet growth.
Producers were astounded by how much food lactating sows could eat each day, and the resulting improvements to weaning weights and rebreeding intervals were equally impressive. The Stotfold scale has become an industry standard.
Alan says that feeding sows three times per day from day 14 post-farrowing does pay dividends with heavier weaning weights and maintenance of body condition. However, water, the important vital and cheapest nutrient, must be provided in sufficient quantity so not to compromise feed intake and milk production. And this is pertinent advice, given that today’s genotypes, and the way breeding herds are managed, are radically different from 20 years ago.
Nowadays batch production is common; outdoor herds account for 40% of the national herd; dam lines are more prolific and piglets are weaned at four weeks of age.
“Our dam lines are lean with fewer body reserves, yet are producing far more pigs,” says Alan. “Sows need to be fed well if they are to maintain condition, wean heavy, strong piglets and avoid subsequent losses in the next cycle.”
It’s worth considering if the drop in sow productivity often seen in second and fourth litters – as highlighted at BPEX’s recent seasonality meetings – is due to a poor understanding of nutritional needs?
In practice, Alan has found that higher-density diets allow his clients to better manage sow condition; helping them avoid the weight-loss/weight-gain roller coaster so often associated with highly productive females. The philosophy works as most of these herds are rearing in excess of 27 pigs per sow per year with an average weaning weight of about 9.3kg.
Stimulating nutrients
But tailored nutrition isn’t just for lactating sows. Science is finding that the physiological demands of increased prolificacy also affects energy requirements at specific periods in the reproductive cycle. Some herds have found that providing an energy boost before service and farrowing can benefit performance.
Producers using DextroSow, a glucose-based supplement that includes specific vitamins such as E, B and folic acid, report improvements to sow productivity. These nutrients are known to benefit reproductive performance during the mating/early gestation period and results from herds using the supplement indicate positive benefits. Weaned sows demonstrate stronger heats and 95% of them are served successfully by four/five days post-weaning.
Developed by Frank Wright Trouw Nutrition, the supplement is top-dressed onto the ration at 150g/sow/day for five to seven days. It provides sows with a brief nutritional boost at critical periods in the reproductive cycle, when perhaps a regular sow diet may not offer quite enough. It costs about 14p/sow/day.
The main ingredient, dextrose, is a very digestible glucose that, once absorbed into the bloodstream, stimulates insulin production. In turn this stimulates the release of luteinising hormone (LH) and follicle stimulating hormone (FSH). These promote the onset of oestrus and encourage the production of large, better-quality follicles, which influences subsequent litter size and uniformity.
“The difference between using a sugar rather than fat or oils as an energy source during the weaning-to-service interval relates to insulin production,” explains Alan. “Fats will increase sow condition, but they don’t stimulate peak insulin levels after consumption like a sugar does, so the effect on LH and FSH release is not the same.”
Late gains
During gestation a sow’s dietary needs are not flat rate, either. Research by Leo den Hartog and Coen Smits, which looked at sow nutrition in relation to piglet development, indicated that foetal weights triple during the final month of gestation. Therefore, providing enough of the correct diet is vitally important at this stage.
Alan agrees that sows rations should be increased during the final four weeks of pregnancy to help optimise sow condition and piglet growth. And it may also reduce the potential risk of low birthweight and non-viable piglets.
“It’s accepted that with higher numbers born, piglets may be smaller and there’s also a greater risk of non-viables,” he adds, “but these factors could also relate to the quantity of feed fed to the sows during the final stage of their pregnancy.”
Most high-performing herds are using gestating sow diets of between 9.48-9.79 MJ/NE at about 2.4-3.4kg/day, depending on the time of year and stage of pregnancy. Some herds are adding DextroSow to sow rations to boost energy levels in the run up to farrowing. With larger litters, the birth process naturally takes longer, and that can deplete a sow’s energy reserves. This slows down farrowing and increases the risk of stillbirths and lethargic piglets. Those using DextroSow say that most sows maintain an active farrowing and numbers born alive have improved as a result.
There’s potential to increase sow output in UK herds and improve efficiency. However, to achieve higher targets producers must not lose sight of the fundamental nutritional requirements needed by their breeding herds. Good management and stockmanship must be underlined by a clear understanding of sows’ nutritional needs at every stage of the reproductive cycle. A feeding strategy founded on good quality diets is a sensible investment.