A barn formula to keep hogs fit and active

Monday, April 2, 2012

An innovative Austrian design offers different floor levels and pens 24 metres long running from fully enclosed straw bedded area through bare slats to fresh air exercise yard

by NORMAN DUNN

Natural ventilation for swine barns is not so well-known on the European continent, so there's a lot of interest in a design pioneered by a farming family in Austria's Steiermark province. It combines straw bedding for lying areas, fully slatted flooring for feeding and exercise, and plenty of fresh air.

Viktor Kickmayer and his family wanted a new barn for their 50-sow, farrow-to-finish organic pork enterprise. They also wanted a design that gave their dry sows, weaners, growers and feeders more action – an environment a little more natural than the usual pens with half a square metre space per animal. The result features pens that are actually 24 metres long, giving the individual animals over two square metres of living room.

Winner of a special prize in Austria for innovative architecture, the Kickmayers' design also won the judges' approval by staying with natural building materials as much as possible. Only the flooring and a few head-high walls are concrete. The framework and most walls are made of locally grown timber.

The layout features a roofed "warm" straw-bedded lying area with a slightly sloping floor so that any liquid runs downhill into the adjacent, unroofed slatted feeding and dunging area with slurry collection tanks below the floor. Self-feeders for dry rations are positioned between the lying area and the slatted section.

From here a series of steps takes the animals down into what Viktor Kickmayer calls a "cold" activity area, which is also straw-bedded. This is roofed, though otherwise completely open to the elements, and allows the animals plenty of sunshine, but also their share of rain and snow.

Generous dimensions means there's 2.3 square metre floor space per animal. This is double the elbow room designated under Austrian law for organic swine operations and four times the minimum for conventional swine raising in the country.

Helping suckling sows to lie down slowly
More attention needs to be paid to farrowing crate dimensions and floor conditions for effective control of piglet crushing during suckling, according to the latest work at the German Köllitsch experimental farm in Saxony.

There, Dr. Eckhard Meyer and his team found in a trial that around 80 per cent of rapid descents by suckling sows – the sudden lying down movement that often catches and crushes piglets – occurred in crates that allowed the sow very little free movement. A slow controlled descent to the nursing position typically took place where there was room in the crate for the sow to lean against one side of the railings on her way down.

Typically, these "careful" mothers went down front legs first and turned as they descended, so that they landed on their side ready for nursing. Where the floor was slippery, the descent was also often too fast, for obvious reasons. In the Köllitsch trials (with 31 sows and 64 movement sequences recorded throughout the farrowing and nursing cycle), the best results in this respect came from sows on plastic flooring, with only 29 per cent of descents classed as rapid and dangerous.

The researchers also found that sow age played an important role, with only 14 per cent of observed descents with first-litter sows being classed as safe and careful. Older sows, although always much heavier, managed to keep 40 per cent of their laying down routines slow and safe.

Genetics are not far behind the crate measurements and floor condition as danger factors for piglet survival, according to the Köllitsch team. The researchers noted that gilts which tended to dump themselves down on litter members without much warning did exactly the same with their next litter, even under conditions that were much more conducive to a slow controlled descent.

For this reason, culling is definitely an option when too many piglets are lost. But so is the adjustment of the farrowing crate width to allow more room for the sow and also the introduction of some sort of non-slip flooring under the farrowing crate.

The Köllitsch experiment in ways to reduce litter crushing deaths also points in an entirely different direction: sow nutrition. The Saxon researchers note that, where sows farrow in less than perfect body condition, they tend to be less co-ordinated in their movements. This inherent clumsiness tends to cause rapid descents to nursing position. Such sows, points out Dr. Meyer, also often have less milk on offer, which in turn means the piglets are more often out of the creep and under the sow looking for something to drink.

Fermenting grain in weaner rations gives swine a flying start
How to get more feed energy out of barley and wheat in weaner rations is an increasing challenge for nutritionists as the cost of cereals rises.

In countries such as Germany and the Netherlands, where hogs are mainly liquid fed, fermenting the grain to help break down more fibre and so release more energy is working well. But how can fermented grain be used effectively in the dry feeding systems much more popular in France, Britain or Scandinavia?

One option looked at by the Danish Pig Centre is the use of a wet mash containing fermented grain for a limited period at weaning – the first three weeks, for instance. Firstly, this could offer a way of easing the often traumatic changeover from mother's milk to a completely dry diet. Secondly, wet mash is a perfect carrier for fermented grain.

Results so far show that this theory is right on target. With equal measures of wheat and barley making up the fermented grain part of the weaner ration, daily liveweight gain (dlwg) and feed conversion were both improved by six per cent post-weaning with 1,700 piglets in the Danish trial.

The trial design had half the animals on a wet mash with unfermented grain in the mix and the rest on mash with fermented grain. After three weeks, both trial and control piglets were transferred to a conventional Danish weaner diet of dry pelleted milled grain, soybean meal, vitamins, minerals and supplementary amino acids.  

During the first three weeks post-weaning, the piglets on the fermented grain returned an 18 per cent better dlwg compared with the control (181 grams against 153 grams). And the fermented grain piglets continued to perform better after both groups changed to the conventional pelleted dry feed, although weight gain performance then was only three per cent better for the former fermented grain weaners.

But the flying start on fermented feed over the first three weeks ensured that, from weaning to eight weeks later, the fermented feed group still returned an overall 5.8 per cent improvement in weight gain. Feed conversion for the fermented grain group was 1:1.94 against 1:1.98.

No inoculation was applied for the fermented grain rations. The grain was simply mixed with water and kept warm for four days in a heated container with agitation. A population of lactobacillus quickly built up and began to degrade the fibre in the grain. Lactic acid content also increased rapidly. The non-fermented grain fed to the control piglets was fed immediately after mixing with water.

Previous work by the Research Centre team has indicated that the efficient degradation of grain fibre by bacteria significantly increases the content of digestible energy of the feed. In fact, when fed to finisher hogs in another trial, fermented grain supplied enough additional energy to allow a two-to-three per cent reduction of grain in the ration.

An extra feed outlet adds up to better average hog performance
Giving the less dominant hogs in feeder pens a break when it comes to getting their fair share of feed can be difficult in conventional liquid systems where a single downpipe per trough is the standard. Everyone knows the scene: the pump starts and the boss hogs are ready and waiting around the downpipe. Naturally, the system is designed so that every hog gets a bellyful, but the dominant ones still get more than the average. Result: a lot of aggravation with injuries and uneven weights in pens when it comes to slaughter time.

How much better would the pen dlwg be if feeding was more balanced? Farmer's son Stefan König teamed up with swine researcher Eduard Burkhard from the animal husbandry department of the Inforama College in Bern, Switzerland, to find out. They added a second downpipe at the other end of the conventional 6.5 metre long trough in a 50-hog feeding pen on the König family farm.

Based on average performances for the same age of hogs in other pens with single downpipes, the mean dlwg did indeed increase – by 20 grams. As expected, this was mainly due to dramatically increased performances by the less dominant hogs. The dlwg of the 25 per cent lightest hogs in the pen shot up by 70 grams.

Two other advantages were immediately apparent, according to Burkhard: There was much less stress and fighting in the pen at feeding time, and the sizes and weights at the end of the feeding period were also much more uniform, meaning less sorting work at loading time.

Extra milk at suckling saves the stress of fostering Instead of investing in a "mechanical sow" for automatic milk to foster piglets where litters are too big, Andreas Paessens from Geldern in northwest Germany prefers to offer additional milk to the litters from day one.

While he does do some fostering between simultaneously farrowing litters, he told the specialist magazine TopAgrar that he manages an average 27 weaned/year/sow from his 170 sows, mainly with the help of careful monitoring during farrowing and through offering supplementary warm milk replacer fresh from day one. He fills round bowls with the extra milk up to three times daily, or according to demand. The supplementary milk is fed up to day 10, with prestarter mixed in with the milk from day 7.

Also investigating this simpler alternative to mechanical sows and fostering is the German Boxberg Centre for Pig Rearing and Pig Breeding, where a system of permanent tip-troughs and pipeline from an automatic milk replacer (Förster Technik) is in place as part of a trial. Sensors trigger automatic refill of the troughs when they are emptied.

Here, supplementary milk is offered in the farrowing pen from day two to day 10 and it's found that the weaker piglets who have failed to establish a place at the mother's teats are usually quick to turn to the alternative supply.

Litter performance at Boxberg has been compared between pens with supplemented milk and those relying on mother's milk alone. Prestarter feed is offered from day 10 in both cases. Some 80 sows and litters took part in the first trials and those with supplementary milk returned 1.8 per cent less mortality to weaning with a four per cent better dlwg to day 21, an average of 306 grams. BP