Breeding for the high-survival sow

Monday, December 5, 2011

British and French research suggest that scoring newborn piglets for vitality and selecting the sows and boars producing the liveliest litters for breeding stock can lead to improved results

by NORMAN DUNN

The aim is producing the high-survival litter. With this target, Dr. Emma Baxter from the Scottish Agricultural College (SAC) in Edinburgh has developed a system that looks at the vitality of piglets in the first 15 seconds of life. But other important survival factors, such as time before the first colostrum drink, are added. And, naturally, the all-important birthweight is not neglected in calculating the piglet survival stakes.

British research has agreed recently that this birthweight should be around 1.6 kilograms, with the emphasis on a uniform litter. "A newborn piglet much heavier than this is not going to help matters much," explains Dr. Baxter. "This usually means there are also much smaller piglets in the batch."

But, getting back to piglet vitality, trial results indicate that a good proportion of this vitality depends on farrowing speed. The Baxter scoring system offers a way of identifying sows with long birth sessions and therefore often larger proportions of weaker and slower piglets in the litter.

Research in France by feed company Lallemand Animal Nutrition confirms the scoring accuracy. Trials in a 400-sow commercial herd there showed that the longer the farrowing procedure lasts, the more low-vitality piglets are produced.

Here's how Dr. Baxter classifies vitality. The first 15 seconds of life is the period used. Zero is the lowest classification and means the piglet has not moved or breathed during this time. Piglets with a score of 1 have also not moved, but have at least attempted to breathe, or have coughed. Resuscitation is usually required for these two classes. Score 2 is awarded to litter members that move and breathe freely, or seem about to start breathing. The top rating (3) is earned by the piglets that everyone loves – active almost the second they hit the ground, with good breathing and attempts to stand within 15 seconds.

In the French herd, the piglets scored as vital were well ahead of litter mates by the third day of life with average daily liveweight gain 30 per cent higher than the worst performers – although most of the survivors in the litter caught up with the leaders in terms of daily weight gain by weaning time in the trial mentioned here. But here, too, the best performers were almost always among the first few piglets born in the litter. Piglet vitality dropped markedly for piglets born three hours or more after farrowing began. 

Back in Britain, Dr. Baxter adds other criteria to the survival calculation. These include the time taken to get that first drink of colostrum. "We've found that a piglet that doesn't get to the udder within the first 25 minutes after birth is more likely to die. For highest survival chances, these piglets should have found a functioning teat soon after that and be suckling their first colostrum within 50 minutes of birth."

There's also a direct link to the age of the sow giving birth. The French research showed that the vitality proportion was highest with young sows up to the fourth farrowing. After five farrowings, low vitality piglets formed a much larger proportion of the litter.

Birthweight in the French herd recorded by Lallemand was almost the same for piglets scoring 2 and 3 (from 1.3 to 1.4 kilograms). Mortality up to day 3 was 42 per cent for 0 score piglets but respectively only nine, six and four per cent for the other scores. By day 21, 53 per cent of the 0 score piglets had died, 33 per cent of score 1, 21 per cent of score 2 and 19 per cent of the piglets scoring 3 for vitality.

One final point made by Dr. Baxter is that sow stress levels can be critical to the length of farrowing and therefore the proportion of vital piglets. Various trials have indicated that a sow that's not confined in a farrowing crate (or is only confined just before birth) and is given straw so that she can make a nest, is much more likely to be less stressed at farrowing with a faster birth taking place.
 
Free feed for forest swine in Germany
Fritz Schäfer from the Vöhler Forest in Hessia, central Germany, is farming swine just like they did 1,000 years ago.

Fritz runs his sows and their offspring through the fall in the 21,000-acre Kellerwald-Edersee forest park. It's the biggest stretch of deciduous woodland in Europe. Trees are mainly oak and beech. This is great for Fritz and some supporting friends, who have formed a special interest club to run around 50 swine in a section of the forest where the fallen acorns and beech mast represent plenty of free feed for the animals.

"This is the way swine were farmed in our great broadleaf forests over thousands of years in central Europe. In fact, fall feeding with acorns and beech mast was still practiced 60 to 70 years ago here," explains Fritz, who also runs a dairy farm on 250 acres nearby. Records from the Middle Ages indicate that more money was earned from the swine in the forest than from timber production!

"The acorns and beech mast provide a valuable feed for our animals, although they also eat roots, insects and earthworms. The sows are wintered in a normal barn and farrow in spring with access to pasture through the summer. Traditionally, St. Bartholomew's Day (Aug. 14) is when they are driven into the forest. They usually stay there over four months before they are brought onto the farms again."

By this time, adds Fritz, some of the growers are ready for slaughter. "There's great demand for the meat, especially from local restaurants," he says. Hams are cured and air-dried for sale in local stores, as are some farmhouse sausages made from the forest swine.

This farmer hasn't calculated the financial returns. "It's not really that kind of enterprise," he admits. "We started off to see if the old farming method was still workable. It was. Then we saw forest feeding as a way of promoting some of the old traditional swine breeds that can live outside without problems. This is why we have sows from the Schäbisch-Hällische, Bentheimer Landschweine and German Saddleback breeds."

He adds that these breeds are dying out in Europe and forming herds to feed through other European forests each fall could help prevent their complete disappearance from the farm animal gene pool.

Quality pork schemes pay off for Dutch producers
The management and swine health checks required as part of a national pork quality assurance system in the Netherlands pay real dividends in overall herd performance. It's no coincidence, say management advisers, that over 90 per cent of Dutch farmers are involved in comprehensive pork quality schemes, while the country also regularly tops European swine production performance charts in efficiency and output.

Last year, national average output was a fantastic 26.5 hogs sold per sow. Each sow in the country produced a total 2.4 tonnes of carcass meat in 2010. And this production had the highest lean meat content average in Europe at 56 per cent (1.36 tonnes of lean meat/sow). As usual, the Dutch farmers were closely pursued in these annual results by the French (1.35 tonnes lean meat/sow), Italians (1.31 tonnes), Belgians (1.3 tonnes) and Danes (1.29 tonnes).

At the same time, though, the 7,000 swine producers in the Netherlands managed to keep mean production costs well below the European average. According to InterPIG, the international working group of swine industry organizations, European production costs levelled at the equivalent of C$2.22 per kilogram of deadweight. InterPIG put the production cost average for the Dutch swine sector at 11 per cent below this, or just C$1.98 per kilogram of pork. There were more efficient producers on a national basis: the French, for example, managed C$1.95 per kilogram. But most were well below the Dutch figure.

According to InterPIG, the Dutch swine sector has real advantages in its structure. Feed delivery and transport of swine to pork processing plants involve relatively low mileages. Economies of scale don't play a great role for the Dutch, however. Dutch sow herds averaged 348 head in 2009, while piglet production units in Ireland averaged around 550 sows and in Denmark nearer 600.

Tight hygiene and management control is the answer to much of the Dutch success, according to the country's Integral Chain Management (IKB) organization, which checks feed, veterinary treatments, hygiene standards and animal welfare on-farm, during transport and at the slaughter house. Maybe the key to IKB's success from the farmers' point of view is that all this control is linked to good sound advice on best management practices for efficient production from every sow in the herd.

IKB is still voluntary for farmers and paid for by levies on slaughter pigs. But the fact that over 90 per cent of Dutch swine producers are members nowadays says it all.

Synchronized feeding boosts weaner intake
It's not so long ago since this column spotlighted a successful experiment at the Dutch University of Wageningen showing that piglets eat most dry feed when they can see their mothers feeding at the same time.

Now, the 300-sow Swine Innovation Centre at Sterksel in the same country (also part of Wageningen University) has taken this concept a step further. Researcher Nienke Dirx is testing systems that deliver piglet starter feed at precisely the same time as the sow gets her feed. To help attract the piglets' attention, a buzzer is sounded each time the feed for sow and litter is automatically delivered by pipeline. This helps towards simultaneous intake.

Piglets certainly eat more with this system, says Dirx. And first results indicate that the eating habit continues after weaning, with the increasing dry matter intake for the simultaneously fed weaners meaning faster weight gain and better overall performance.

"We don't have any solid figures so far, but our observations indicate that weaners from the simultaneous feeding farrowing pens are eating more and certainly feeding faster than piglets from conventional litter feeding."

Next year, a more comprehensive trial is planned to compare weights of weaners and subsequent performance. Also to be tried in 2012: experiments on commercial farms where both sow and litter will get simultaneous feeding with liquid diet. "We expect the weight gain performance for piglets in this variation to be the best of all," adds Nienke Dirx. BP