Where loose housing brings more piglets per sow

Wednesday, August 1, 2012

The coming Jan. 1 deadline for the end of dry sow stalls is presenting problems for some
countries. But others have been running loose housing systems for years with good results

by NORMAN DUNN

Animal welfare pressure groups and member governments in the European Union (EU) have decreed that it's "goodbye" to dry sow stalls as of January next year. Non-restraint group housing of the gestating animals has already been completely introduced in many countries. But, from January on, more floor space per sow will also be written into the EU rule books –  from the present 1.84 square metres per sow to 2.25 square metres for groups of up to 39 sows.

The forerunners in this respect – Britain and Sweden and (outside the EU) Switzerland – were put under pressure first by their respective welfare organizations and have had national legislation banning dry sow stalls in place since the beginning of the millennium.

But, with just six months to go at time of writing, only 60 to 70 per cent of Germany's sow population was in group housing and just a tick more than this in Dutch and Danish herds. In southern Europe, the situation is feared to be much worse. Many observers say that there's no way many of the countries will be able to meet the group housing deadline.      

That apart, how will the new system – with confinement only allowed for the initial insemination period and a few days before farrowing – affect performance? Farmers looked to Britain at the time of its changeover to try and assess what might happen.

There's no doubt that sow performance there tumbled when loose housing was adopted. But a lot of other factors were involved at that time, including foot-and-mouth outbreaks and other disease problems. The latest available figures (2010) still put Britain and Sweden at the tail end of the European performance league table for annual production of weaners per sow with 22 and 23.3 respectively. The leaders in this respect are Denmark with 28.1 weaners per sow, the Netherlands with 27.7 and France with 26.6.

On the other hand, as swine expert Martin Looker tells me from England, the development of loose housing systems has encouraged breeding companies to go for more docility in their sow lines over the last 10 years, which has made management easier all round with some hybrids.

More encouragement for loose housing comes from practical experience in the Netherlands, where a multiplier changed the dry sows in his 280-sow herd to loose housing in 2011. In a report for veterinary producer Boehringer Ingelheim, farmer Ad van de Pas showed how he had increased his weaner per sow figure over the 2009 national average of 27.3 to 28.9 (although the last figure had only been collected over a three-month period).

In fact, problems with aggression between sows at the beginning of the system's introduction gave a poor average for the whole of 2010 of just 26.3 in this respect. Again, compared with the national average (the majority of Dutch dry sows were still in crate or stall confinement systems at that time), his sow fertility figures were consistently better with 2.45 litters per sow per year instead of 2.37 and a farrowing rate of 89 per cent (against 86 per cent).

Two years of testing loose housing systems by the Westphalia Chamber of Agriculture at its Haus Düsse Centre for Agriculture featured a large dynamic group in a single barn with lying bays and central slats. Groups of 12 sows join the main group every week three to four days after serving.

First-litter gilts were not run with the large group. The system was introduced in 2005 and, here too, after about a year of starting problems, performance improved to surpass that achieved when the dry sows were kept in stalls (2004 figures) with 2.35 litters per year compared with 2.29 and 22.74 piglets weaned per sow per year versus 21.05.

Main initial problems, according to the Chamber of Agriculture, included aggression and biting at the electronic feeding stations. These problems were less evident later on. Feet and leg problems seemed to increase with loose housing, too.

The researchers felt that more intensive selection was needed to overcome this problem. The Haus Düsse scientists employed an automatic heat-detecting system via the earmark transponders with the length of time that the sows hung around before adjacent boar pens recorded by the computer. If this period lasted more than 10 minutes, the sow was electronically tagged as a return to service.
Weeding out aggressive gilts

Is it realistic to weed out aggressive gilts before they start breeding with the aim of reducing fighting and injuries amongst loose-housed sows later on?

"Yes," say University of Kiel researchers. But – wouldn't you know it? – the female trouble-makers were also found to be the best performers in the associated north German university trial.   

Especially now that EU swine producers are preparing for universal loose housing of dry sows by the beginning of next year, there's plenty of discussion on ways to avoid the significant losses that can be caused by biters and fighters in the breeding herd.

The Institute for Animal Breeding and Management at Kiel University decided to look at the lifetime history of the brawlers to see if they could be identified early on.

Using video monitoring over 48-hour periods, the research started with a batch of swine right after weaning. Then the same groups were monitored again 40 days later. Lastly, gilts from the groups were monitored for behaviour just before being mated for the first time.

The Kiel researchers note a significant correlation of the aggressive members identified 40 days after weaning and again as breeding gilts. But the trial report finds no real link between earlier weaner behaviour and later aggressive traits. Scrapping for very young piglets was mainly play, they argue. Later on, the motives were deemed to be more feed-based (who gets their snout into the feeder first), or general group hierarchy struggles.

The young females that started fights most often at around 70 days of age were the same ones responsible for biting and bullying in the breeding herd later on. But these animals also returned the highest liveweight gains in the trial. So far, though, there seems to be no significant difference between aggressors and lower ranks in later breeding performance.

Interesting is the Kiel conclusion that the dominant and most aggressive young gilts ended up with more scrape and bite injuries than the animals they continually attacked. Less surprising was the finding that the swine starting the fights were nearly always the ones that won them.

Producing your own high quality replacements
Commercial hog farms in Denmark and Britain are increasingly harnessing breeding company computer data to breed quality replacement hybrids from their own stock. The available computer capacity has made analyzing the breeding potential of their top sows much easier, and the breeding companies match up the best boars to complete the process. Main advantage: no import of animals onto the farms and the associated dramatic reduction of disease risk.

The Danish breeding company DanBred offers commercial breeders its GenePro selection system to analyze the breeding value of sows in the herd. Highest ranking sows in terms of fertility, reproduction and offspring performance can be identified as great grandparent stock, less highly placed females as GP sows to produce the F1 gilts for each commercial herd.

This approach, says DanBred development manager Simon Guise, now allows commercial producers to breed the same quality of females that so far have only come from specialist multipliers, although it certainly needs AI input from top-ranking sire lines. Built around a worldwide genetic database, the Danish system uses weekly inputs on herd performances and an analyzing system that pinpoints the most suitable matching of boar and sow for herd-internal progress.

Another relatively recent introduction for herd-internal replacement stock is a Best Linear Unbiased Prediction (BLUP) breeding program adapted by the Irish-based breeding company Hermitage Seaborough. This needs careful herd performance recording – for instance, litter size, numbers weaned, farrow-to-service interval. Help in this respect is available from a dedicated herd management program offered by the breeding company. All details are then fed into the worldwide BLUP database and the end result is a performance index for all sows in the respective breeding herds. Also computed is an appropriate mate selection index giving the best AI boar for crossing with each particular sow.    

Swine herds that have so far introduced this herd-internal replacement system report some pretty dramatic results. For instance, one unit using a criss-cross breeding policy between large White and Landrace, backed by the BLUP recording and breeding index, reports weaner production per sow had risen from 23 in 2010 to 26.6 by the beginning of 2012. In the feeding houses, feed conversion of the slaughter offspring from the herd had also markedly improved.

The companies involved say the programs are increasing farmer interest in more intensive recording as well as reducing overall costs usually charged for importing new gilts from multipliers.

Coming soon: Intelligent temperature control for creeps
According to the designer, there's up to 30 per cent power savings – as well as improved piglet performance – from a so-called "intelligent piglet creep cover" now launched on the Swiss market. The creep,  complete with two 150-Watt heating lamps and infrared sensors that continually measure the temperature, continually reacts to changing conditions. The sensors and supporting software not only alter the height of the creep cover but also can dim or brighten the heating lamps for even more temperature control.

Standard setting for the cover is 90 centimetres above the insulated creep floor. But, when the piglets are young, the cover is lowered via a pulley and cord system to reduce the volume of air that has to be heated. The heat energy emitted is mostly direct radiation, according to the manufacturer, Globogal. This means the piglets themselves are heated rather than the surrounding air, another reason why heating costs are claimed to be reduced by the creep design. BP