Bridging the post-weaning growth gap

Saturday, August 8, 2015

Irish research suggests that daily gain, feed consumption and feed conversion ratio through to 10 weeks were all significantly better for the piglets weaned at five weeks rather than three or four

by NORMAN DUNN

Irish research is taking a good look at the negative dip in the piglet growth curve after leaving the farrowing pen and the solutions include a longer suckling period or supplementary milk replacer.

On paper, adding another week to the suckling period threatens a big dent in hog production profitability. Certainly, this strategy improves weaning weight and general health – a welcome boost to help bridge the usual performance gap in the first few days post-weaning.  

Ireland's swine production advisory department recently reviewed a series of trials testing better ways of maintaining weaner growth in this early period. At a conference hosted by the republic's Agriculture and Food Development Authority (Teagasc), researchers and advisers presented solutions for this profit stealer.

Weaning in Ireland is usually at around 26 days. In 2013, Dr. Lisette Leliveld tested the effects of weaning at three, four and five weeks in Teagasc trials and found that the last group handled the post-weaning challenge much better than the rest. Daily gain, feed consumption and feed conversion ratio (FCR) through to 10 weeks were all significantly better for the piglets weaned at five weeks.

Predictably, the weight of the five-week weaners was much higher, an increase of 45 per cent over three-week weaning and 22 per cent more than the four-week weaners. The post-weaning performance dip was largely ironed out by later weaning. Average liveweight at 10 weeks was eight per cent higher for the five-week weaners over the average for the rest. Daily liveweight gain for the five-week weaners was just short of 20 per cent higher than the average of the other two classes. Feed consumption was 13 per cent more and FCR was 1.43 against an average 1.56 for the others. Mortality to 10 weeks in this trial was 14 per cent for the three-week weaned group and only four per cent for the five-week group.   

The Irish research underlines a series of other strategies which have a positive effect on immediate post-weaning piglet performance. One of the most important, and easiest to activate, is ensuring a comparatively high water intake. Think about it: before weaning, daily water intake equivalent per piglet is around 680 millilitres. In the first day after weaning, a trial recorded intake ebbing to around 290 millilitres and only averaging 442 millilitres over the first week. Crucial here, say the Irish advisers, is adequate access for every weaner to always clean and fresh water – and no restrictions to flow rates in the first weeks. After all, numerous trials have proven that restricted water can reduce weaner weight gain by as much as 15 per cent.

As for feed, the advice for weaners in their first days includes pushing as much energy as possible into the rations. At the Teagasc Food Research Centre in Moorepark, pre-weaning growth rates to 26 days are as high as 260 grams per day. Feed intake immediately post-weaning has to be extremely good to keep up an increase in this performance. Once again plenty of water is crucial, as is using high-energy rations with milk products. Irish research in 2005 showed that the time taken to reach a 97-kilogram slaughter weight was reduced by five days when the post-weaner starter diet contained a high level of dairy product ingredients, such as dried whey.

Also emphasized in trials is great performance potential if milk replacer is offered post-weaning. It is definitely labour-intensive, but Irish work shows that offering this liquid plus starter diet for four days after weaning can increase daily gain by 20 to 30 per cent in the first week, compared with feeding a dry starter on its own. The part-liquid approach encourages dry feed intake.

Dissection of weaners on this diet reveals that more fat and protein is converted into body tissues and that intestinal villi tend to be better developed than in pigs still suckling with their mothers or already on a dry diet.  It is accepted that low post-weaning feed intake can be responsible for poorly developed villous height and that this, in turn, impacts growth rates after weaning. Offering milk-based feeds during this period appears to maintain good gut development and helps beat the post-weaning growth dip.

These strategies naturally come with heavy costs. So any improvement has to be checked against extra expenditure, warn the advisers. But, especially where lighter born piglets are already a problem, beating the post-weaning performance dip could be the key to better overall returns.

Egg labelling system for pork?
The European Union production codes for store-sold eggs should also be applied for pork, says the influential European Green Alliance party. The egg code was introduced in 2004 and is applied Europe-wide with information printed on every shell giving country and farm of origin along with production method: organic; free range; deep litter or cages.

The movement to secure similar information for pork labelling has started in Germany where the Green (ecological protection) party with 63 seats (10 per cent) in parliament has tabled a motion to this effect. The suggested pork code for adding to labels is 0 = organic; 1 = access to outdoors or free-range, and straw bedding in housing; 2 = pen space over and above legal minimum standards; 3 = legal minimum standards only. Current minimum standards in hog production include a minimum space of 0.75 square metres per feeding hog from 50-100 kilograms and a minimum 2.50 square metres for an older sow during gestation. Under point 2, the Green party wants to see 30 per cent more pen space per hog.

Pork is already following eggs this year with the introduction of a European label code giving country of slaughter and rearing and feeding location. Despite yearlong pressure from national consumer organisations, the European Union still refuses to make country of origin (i.e. location of birth) mandatory on meat labelling. However, programs to protect national pork production in some countries, notably Britain, have resulted in some retail outlets agreeing to country of origin on labels.

The swine sector in Britain and meat retailers there also promote a range of production certification schemes, including the "Red Tractor" program with standards in some cases above the mandatory requirements. For instance, a Red Tractor rule prohibits castration for male hogs, a practice still allowed in most European countries

Tired of fostering? Try a cuppa!
Supplementary milk substitute in the farrowing pen is causing more interest in Europe. The trend means large litters no longer need to be split-up – with all the associated extra work of fostering.

There are now various cup systems for automatic metering of fresh-mixed milk substitute to piglets in farrowing pens and they are certainly not cheap. But intensive testing by agricultural institutes in Germany indicates the systems can offer solid extra profit at the end of the day.

Extra-large litters are becoming a big problem. For example, where University of Giessen scientists went to test a one cup system, they chose a 1,000-sow commercial unit with Danish DanAvl sows. Random selection of 132 sows for the experiment all produced 19 live piglets per birth, or more (average 19.4).

Normal farm routine would mean fostering and/or removal of batches to pens with mechanical milk substitute feeding. The attraction of supplementary milk with a cup, or small trough system in the pen is that this should work with the large litter kept entire.

One point already established for the cup systems is that they help nursing sows, too. At the German Boxberg State Swine Breeding Institute (LSZ), researcher Stefanie Baumann found that sows lost an average 37.58 kilograms in bodyweight over a suckling period with no supplementary milk feeding system. Where extra milk was available to litters, sow weight loss under the same conditions (weighted for litter size) was 10 per cent less at 33.89 kilograms.

The LSZ work, carried out four years ago, also showed piglet losses to weaning with such a cup system were reduced by an average 1.82 per cent and that piglet weight at weaning was 0.23 kilograms more. This trial, however, showed no significant difference in post-weaning performance between control litters and those that had been offered supplementary milk during suckling.
Advantages in litter growth and survival are more clearly defined in the Giessen University trial. The financial side was also looked into and the result was a definite economic advantage for the best performing herds.

The 132 sows selected were split into two groups. One had milk substitute offered to litters from day 2. Both groups were offered pre-starter rations from the second week, with weaning after four weeks. Litter weight at weaning averaged 84.1 kilograms for the milk supplement group and just 64.4 kilograms for the control. Some of the advantage won by the "milk cup" litters was due to far better survival figures.  Losses to weaning averaged 15.4 per cent for the supplemented group and 22.5 per cent for the control litters, unusually high for this farm. Main cause of death in the latter: crushing.

If the cup system was to be used for all 1,000 sows on this farm and capital investment depreciated over 10 years, costs for extra labour, electricity (for mixing and pumping the milk substitute), and for the milk powder itself come out at about $3.97 per piglet. However, this still leaves around €70,000 more profit from more piglets and heavier weaners. Breaking even for this system under German costs would mean that weaner numbers per litter would have to increase by 0.9. The farm helping the Giessen scientists with their trial managed an extra 1.9 weaners per litter.

A computer warning system for farrowing
University of Kiel scientists in Germany are completing a computerized early-warning system for farrowing, based on sow ear tags that record the animal's head movements. The latest versions of these tags also monitor sow temperature.

The background to this development is that sows generally become more agitated as birth approaches and, a few hours before farrowing begins, often add to general unrest by starting typical nest-making movements. Based on the movement patterns, the Kiel researchers have fine-tuned software so that the build-up in movements right up to farrowing time can be fairly accurately predicted and a suitable warning given to herd manager or farmer via computer or cell phone.

The software is flexible enough to permit a predetermined time lag for early warning, for instance four or eight hours before farrowing begins. There's even the opportunity for two-step alarms so that staff can plan even better to be present at farrowing. All information from the ear tags (from MKW Electronics in this case) is sent direct to the herd computer via a router in the farrowing house. This enables graphic presentation of the movement patterns for individual sows so that the trends can be monitored over a matter of days, allowing plenty of time for management planning. BP