Graeme Kirk reports from the 2013 Provimi Nutrition Seminar, held in Barcelona in November
Professor Georg Dusel
Kicking off the swine sessions at Provimi’s Nutrition seminar, Professor Georg Dusel, of Germany’s Fachhochschule Bingen University of Applied Sciences, addressed some practical ways to improve the economics of piglet rearing.
His first goal was to reduce pre-weaning and rearing mortality to less than 10%, and the key to this was correct gestation feeding to achieve piglet birthweights averaging 1.4kg.
Feeding in the prenatal, perinatal and lactation phases had to meet the high performance level of sows with the genetic potential of more than 30 pigs/year. This meant meeting the energy requirement for sows with more than 14 foetuses; providing the right fibre sources during feeding; and feeding to optimise the yield and composition of sow milk in early lactation.
Interestingly, Professor Dusel said that while trials had shown that giving piglets free access to supplemental milk from farrowing didn’t increase their performance, there was evidence that this approach could be used to minimise the loss of body condition score and backfat from the sow, leaving her in better shape for her next parity.
In fact, he suggested there was a good economic case to use the strategy to reduce sow feed costs as they wouldn’t need to each as much to replace backfat lost during lactation.
Professor Dusel also talked about research that had been carried out looking at teat the effect of teat order and location on piglet growth. He said that studies had found that the order that piglets took on the sow’s teats was 55% decided by day two, 80% decided by day three and 97% fixed by day five.
The research showed that the order was governed by birthweight, with the largest pigs at the front and the smallest pigs at the rear. This effect appeared to be carried on by a study that showed a piglet’s position on the teats was directly linked to its growth rate during lactation.
Piglets feeding from teats at the front of the sow, in particular rows one to five, were found to achieve an average daily gain substantially higher than those on rows six to eight. In fact the difference could be as much as 45g/day.
Dr Ruurd Zijlstra
In the first of two presentations he gave at the seminar, Dr Ruurd Zijlstra, of the University of Alberta, addressed the use of milk replacers to optimise the growth potential of pigs.
He said that a USDA study had shown that starvation was responsible for 40% of non-crushing mortality in pre-weaning pigs, and – while acknowledging that solid data was scarce – went on to suggest that the milk requirement of a litter of piglets exceeded the output of the sow from day 10-12 onwards.
Piglets were capable of growing at faster rates than they could achieve on the nursing sow alone, and the problem was only getting worse thanks to larger litter sizes, he added.
Dr Zijlstra said that piglets were limited in what they could eat by the enzymes present in their gut, and that their ability to better deal with vegetable protein developed between the age of four to five weeks. Liquid diets could therefore hold promise of optimising growth performance in early-weaned piglets.
In his second presentation, Dr Zijlstra outlined a vision for modern swine feeding. Because pigs were omnivorous, he said, this meant that it was possible to maximise the opportunities to include feedstuffs that weren’t edible by humans into pig diets.
Among the alternative feeds he suggested were crops including cereals that didn’t make the grade for human consumption; non-oilseed pulses; and oilseed. Co-products that could be used, meanwhile, included dried distillers grains with solubles (DDGS), crude glycerol and oilseed meal or cake from the biofuel industry; and oilseed meal or cake, wheat co-products and sugar beet pulp (among others) from the food industry.
Providing food for thought, he said that behind every product on the supermarket shelf there was at least one co-product.
Dr Zijlstra said that pigs could successfully convert a wide array of feedstuffs into pork, but the key to this using this strategy was to use modern feed evaluation processes to ensure quality and safety, and to let performance targets and economics drive your feed formulation.
It was certainly possible to use co-products to reduce feed costs, but other factors to bear in mind included the fact that there was likely to be a large variability in quality of the feedstuffs, which would take careful management. Specific risks from mycotoxins and residues could be an issue too, and pork quality might also be affected by using novel feedstuffs.
Anyone following this route of feeding needed to be aware that there could be challenges to achieving cost-effective, predictable growth that produced the carcase characteristics and pork quality the market required.
A global pig technology specialist with Cargill, Simon Tibble’s presentation reinforced how the correct management at weaning helped pigs achieve their best possible lifetime performance.
He said there were a number of challenges to post-weaning performance as the number of piglets weaned had increased significantly in recent years, leading to a decline in piglet weaning weights.
However, the key to success was maximising daily liveweight gain as the piglets that grew fastest post-weaning would also be those that grew fastest to slaughter.
Early post-weaning growth was a reflection of the adaptation process the piglet made from sow’s milk to solid feed, Mr Tibble said, and post-weaning performance could explain up to 30% of the variation in growth through to slaughter. Explaining that the post-weaning feeding programme represented just 6% of the total feed cost, he made the point that this was a small investment for a better return at finishing.
Describing the ideal post-weaning diet, he said it should contain highly digestible raw materials that complimented the immature digestive system of the piglet , while stimulating consumption to help in gut maturation.
It should also maximise consumption to ensure the piglet consumes sufficient energy and nutrients to avoid the mobilisation of body reserves, and it should adjust the piglets to a simple and relatively lower cost diet as quickly as possible.
Mr Tibble suggested following different feeding strategies for small piglets, with the smallest 20% getting targeted nutrition and offered a higher-quality digestible feed for a longer period. A gruel/soup feed post weaning would also stimulate appetite.
But he also warned that big piglets needed careful management as they were at risk of living of body reserves and making a slow transition to solid feed.
Professor Bas Kemp and Dr Lia Hoving
Sustaining the performance of sows with high genetic potential, and then passing that performance potential on to future generations, was the topic addressed by Dr Lia Hoving of Provimi and Professor Bas Kemp of Wageningen University.
Dr Hoving looked at sow performance and made the point that pre-mating condition could affect subsequent litter uniformity.This could be compromised by severe condition loss during the previous lactation.
One reason for weight loss in sows was having the temperature in the farrowing room too high. Feed intake was depressed by 2.4MJ DE/degree C for every degree above 16C, she said, adding that the ideal temperature was at or below 18-12C.
Professor Kemp’s portion of the presentation looked at ways of influencing piglet behaviour through their interaction with the sow, and through perinatal flavour learning.
It’s long been known that human babies can pick up flavours through the amniotic fluid in the womb. Research in France showed that newborn babies recognised the smell of carrot juice when their mothers had drunk it during their pregnancy.
This same process can be used in piglets to reduce the neophobia effect when they’re introduced to new foods, making the switch to solid diets easier.
In trials, aniseed was added to gestating sow diets and later to the diets of their piglets. Because the piglets recognised the flavour and they linked it with the safe environment of the womb, the stress usually linked to the introduction of new feedstuffs was reduced and intakes were increased.
Professor Kemp also spoke about trial work where piglets were given the opportunity to learn how to eat from their mother.
When exposed to new feedstuffs in the presence of the sow, where they all had access to the feed trough, the piglets displayed less neophobia; were quicker to touch the food (19 seconds versus 111 seconds when the sow wasn’t present); and consumed more food.
Further work explored whether the sow needed to participate in this social learning approach to teaching piglets about new foods or whether simply letting the piglets see the sow eat was enough. It was found that both observing and participation were effective in reducing neophobia.
Just observing the sow feed from a trough would reduce neophobia in piglets exposed to feed in a similar trough, but if given the opportunity, the piglets would prefer to eat from the same trough that they saw the sow using.
Summing up, Professor Kemp said that perinatal exposure of piglets to flavours in the sow diet could facilitate the weaning process if the flavour was also present in the perinatal environment. He suggested that the aromatic qualities of the added ingredient was probably more important than taste, but an additive that had both would be best.
He added that allowing the piglets and sow to eat together at the same place using a similar-flavoured diet was another way to get the same effect, and suggested that this was an approach that could be taken in some freedom farrowing set-ups where the sow had more opportunity to move around and interact with the piglets.
The most important message of the work, however, was that producers had to find ways to stimulate the early onset of creep feeding during lactation to maximise the opportunity for feed intake at weaning and prevent any check in growth rates at that important stage.