The Netherlands looks to natural swine housing

Wednesday, August 10, 2011

While Europe tends towards intensive swine barns with forced ventilation and expensive air filtering systems, Dutch engineers are emphasizing more natural means

by NORMAN DUNN

By focusing on natural ventilation, continual manure removal and outdoor access for animals, the swine sector in the Netherlands is investigating an even more sustainable approach to production.

The watchwords in a new housing concept being developed by a consortium of Dutch farm building companies and livestock farming experts at Wageningen University are low energy demand, minimum emissions and higher animal welfare.

The so-called Starplus 4 PPP barn is steel-framed with large windows. Flooring is mainly solid because straw litter is foreseen as an important factor in animal welfare and emission control. An underground canal with slatted cover runs through all pens and houses a conveyor belt for regular manure removal.

"The manure is automatically taken out of the housing in this way at least every three hours," explains Hans Hutten, who works with Wopereis Staalbouw, one of three agricultural engineering firms involved in the project.

"Regular removal of manure reduces free ammonia in the swine building. Thus, ammonia emissions are avoided as well as those of other climate damaging gases. The manure is subsequently fermented for biogas production, so we are also producing energy in a way that protects the environment."

A channel under the manure belt separates urine and this flows naturally into an enclosed storage through a transmembrane chemo-sorption ammonia stripper. The stripper leaves a concentrated liquid ideal as fertilizer.

No exact building costs are available so far because the project, which has already been awarded a top sustainability certificate from the Dutch Ministry of Economic Affairs, Agriculture and Innovation, is still in prototype mode. A small unit for 60-70 hogs is currently being completed at Sterksel Pig Research Station, the leading farm-based swine research centre in the Netherlands. Two further Starplus buildings for 200 and 2,000 hogs respectively are to be completed this year. Wopereis Staalbouw claims that costs will work out slightly lower per animal place than those for conventional slatted floor and forced ventilation housing.   

Running costs will be significantly lower, however, according to Hutten, mainly because the natural ventilation system and the large window areas save a lot on power. The first buildings this year will be for feeding hogs only. Later, Starplus buildings adapted for sows and weaners will be introduced.

"We'll be lobbying for the pork produced from such housing to be specially labelled and sold as a brand. This means that the hogs fed through such a welfare-based system should earn a bonus at the store counter," concludes the engineer.

Virtual farming in England – an online hit
It was the idea of Britain's National Trust (NT), an organization with the life-purpose of preserving traditional countryside, along with stately homes and castles. The NT is itself a landowner and has now opened up one of its farms so that thousands of "online farmers" can help manage the business, including swine production. After just a few weeks of existence subscriptions for membership of the "MyFarm" website had already moved into the four-figure realm.

The NT says it wants all participants to get involved and up to around 10,000 are expected to join in the initial year. They'll be encouraged to contact the real farm manager, Richard Morris, with management and business suggestions and, through this, to get involved in day-to-day decision making. One good result, says the NT, will be a better understanding of farm production and its problems by members of the public, people who previously had little to do with hog production or any other farm enterprises.

But this online farming isn't really a game. The right to manage the very real 1,200-acre farm near Cambridge in eastern England is bought with subscription equivalent to C$50 a year. But there are lots of perks, such as free visits to the farm with the family to check up on the stock.

Young sows benefit from extra feed after service
Giving your young sows extra feed after service following their first or second litter is worth at least two extra piglets in the subsequent litters, according to work at Sterksel Pig Research Centre in the Netherlands and Wageningen University Livestock Research. There, researcher Lia Hoving and her team divided 197 young sows into four groups and fed them different diets from the second day in-pig to day 32.

The first group acted as control with a standard gestation feed at 2.5 kilograms per day. Sows in the second group had this ration increased by 30 per cent, while the third batch was offered the standard 2.5 kilograms but with 30 per cent higher protein content. Standard rations used in group one were also fed to the fourth group, although litters from these sows had been weaned a week earlier than the rest: i.e. at three weeks.

The results showed no real advantage for the extra protein and earlier weaning strategies. But the sows on 30 per cent more daily rations came through gestation in better condition and had average litter sizes of 15.1 born alive compared with 13.1 for the control group members. The sows with the 30 per cent higher rations produced a lower percentage of litters with 10 or less piglets and a higher than average number of litters with 17 or more born alive.

The strategy wasn't a complete success, however. The researchers at Sterksel report that sows in the second group showed a higher return to service after first insemination compared with the control sows: 23 per cent against just 10 per cent. It is reckoned, however, that this could well be a one-off result and not have any bearing on the extra feed. 

Added feed cost was around C$6 per sow for the group two sows at Sterksel.

PRRS: a quick way to test the whole herd
No clinical signs of PRRSV (Porcine Respiratory and Reproductive Syndrome Virus) in the herd doesn't, of course, mean the disease is not there. That's why blood tests are needed so that status can be estimated.

So far, blood tests of relatively large numbers of animals are needed. This, along with the subsequent rt PCR/ ELISA analyses only add to the expense.

But there's now a much cheaper way of spotting sub-clinical infection thanks to a recent breakthrough in the Netherlands. The new way means only relatively few blood tests are required – and just from a certain age of animal.

A veterinary team working for GD Animal Health Service took 10 test herds with both breeding and feeding animals and analyzed over 100 blood serum samples per farm from five age groups – sows during early and late gestation, weaners at nine weeks old, and feeders or gilts at 16 and 22 weeks.

The ELISA results indicated PRRSV presence in nine of the herds. Working out the odds of identifying herd infection in one particular age group, the scientists found that almost 100 per cent proof of virus existence in the whole herd could be found by analyzing the blood serum of the hogs between nine and 16 weeks of age.

This detection strategy worked for eight of the test herds. A total of 12 blood samples was taken from this age group by the researchers, half from nine-week-old hogs and the rest from animals at 16 weeks. Both rt PCR and ELISA tests were carried out with the result giving a cost-effective first evaluation for PRRSV infection where no clinical signs were present.

An automatic feeding unit that can handle 8,500 hogs at a time
It's the biggest in the country: fully slatted with capacity of 8,500 hogs at a time and a staff of just two. The Decoy unit, designed and run by swine breeder JSR, pens feeders in groups of 350-400. But they are still on phase feeding because the animals have to pass through a weighing sluice gate every time they go to the trough. Then, depending on weight, they are directed to one of three dry feeding areas, each with a different ration. After feeding, they move automatically back into the main group.

The fully computerized system uses this continual weighing to assess weekly slaughter numbers six weeks ahead. When slaughter weight is reached, the sluice gates simply direct the hogs into the appropriate holding pen with the information sent straight to the unit office.

The C$3.33 million JSR Decoy unit takes weaners in groups of 800 and splits them into single-sex pens of 120-150. After 12 weeks of growing-on with rations that change from initial wet mash to dry feed, the hogs move on to the giant finishing pens for a final 12-14 weeks.

Management policy is to provide plenty of space with 0.47 square metres flooring per animal right through the system. Welfare strategies include minimum changes for each hog. Original group members remain together right through the system, although groups are joined, still remaining single-sex, for the finishing period.

JSR measures its efficiency mainly on the final conversion rate: kilograms of pork produced from one ton of feed. And, at the moment, it says this figure is 325 kilograms with the hogs slaughtered at an average liveweight of 108 kilograms, deadweight 83 kilograms, the market in Britain being for comparatively lightweight carcasses.

Searching for the contented pig
Drs. Sandra Düpjan and Birger Puppe from the animal behavioral physiology department of Dummerstorf Research Institute in northern Germany are seeking scientific evidence that swine have feelings – that they can be contented and what we humans would understand as happy.

Now, this is dangerous ground for any scientists who want to be taken seriously by the farming sector. There are plenty of people who have spent a lifetime managing swine who would say the claim that they have feelings just like us is – well, hogwash.

But, on the other hand, why not? The two Dummerstorf researchers are scientifically cautious with their discoveries so far. They point out, though, that if a feeling of well-being can be scientifically recognized then this would be of great value in design of swine housing and management systems – especially nowadays when there's so much interest in animal welfare from pork consumers and others.

Düpjan and Puppe are testing the reactions of swine to the different vocalizations of other swine, and to varying physical conditions, through recorded heart beat frequency and variability, and the level of so-called stress hormones in the blood.

They point out that alarm, fright or fear and perhaps warning calls were always at least superficially recognizable and that the rapidly expanding science of analyzing swine sounds with computer software (often developed at Dummerstorf) is closely mapping this area of knowledge at the moment.

But now a breakthrough points the way ahead to identifying the feeling of well-being. This started off with experiments featuring laboratory rats in Britain, where a method was discovered of analyzing whether animals were optimistic or pessimistic under precisely defined situations.

For instance, if they fail to find feed in a certain container, will they keep looking? Or will they just give up? In human medicine, optimism as a characteristic has long been associated with a certain satisfaction with one's current situation – or contentedness, if you like. This association seems to have been proved with the rats in the British trials.

Now the scientists at Dummerstorf are trying to establish the same link with swine, perhaps a step further down the road to treating animal welfare as an exact science. BP