Management of Lean Genotype Sows
Newly weaned pigs arriving at weaner pens are the highest – health – risk animals in a production unit. This makes their initial management and care vitally important. This paper will attempt to summarise steps to take in the successful transition of vulnerable weaners at 21-28 days of age to healthy juveniies of 33-35kg at 70 days of age.
1.1. Before arrival
Managing weaner pigs begins before their arrival. The room and all equipment must be properly washed and disinfected. Ventilation controls should be checked for functionality and properly set, allowing time for the rooms to become warm and dry before the piglets arrive.
1.2. Upon arrival
Piglets weaned between 21 and 28 days of age generally range in weight from 6 to 9 kg At arrival, pigs should be sorted according to size and body condition. Grouping by weight allows to more closely match the pigs’ weight to the diet provided. This is important because of the expense of these initial diets and the range in the digestive capabilitY of the pigs.
1.3. First 36 hours after placement
During the first 36 hours afterweaning, pigs need to find the water and feed. Pigs should NOT be limit-fed after arrival. Feed can be provided several times per day. Pigs should be observed to ensure they have found the water and are beginning to develop feeding behaviour.
1.4. 36 to 60 Hours after placement
This is a critical period for identifying pigs that may require extra attention. Two to 4% of pigs will be candidates for individual attention, and identifying them is always the most difficult part of the process. To identify at-risk pigs while taking a walk-through of the weaner pool, look for:
Small pigs with low body-fat reserves must have a ready source of energy to keep small pigs from starving. In high-health-status pigs, signs of anorexia, depression, and dulleness are more likely to be caused by lack of energy than infectious disease.
1.5. Remainder of weaner period
Routine observation during the whole weaner period remains vital for the early observation, identification, and treatment of disease.
1.6. Eating behavlour of pigs and feeder space requirements
Understanding the eating behaviour of pigs can help producers maximise feed intake and, as a result, promote pig performance. How often pigs eat is related to theirageand size. Finishing pigs eat approximately 7 to 9 meals per day, weaner pigs eat more frequently, and recently weaned pigs eat 15 to 20 meals per day. Management factors also can influence meal frequency. For example, individually housed pigs eat more often than pigs housed in groups, and as group size increases, eating frequency decreases.
2. Weaning weights
In general terms the better the weaning weight of a piglet the better the performance in the immediate post-weaning period. Mahan and Lepine (1991) reported that by improving the weaning weight from an average of 4.5kg to 80kg the days to slaughter at 1 05kg were reduced by over 10 days for sows farrowed indoors and nearly 20 days for outdoor reared sows. Similar results were reported by Campbell (1989) who demonstrated that an extra 1,8kg at weaning was worth over 5kg at 78 days of age.
This work has been substantiated by analysis of data from SCA FEU collected during 1999 using over 6000 piglets. As weaning weight increased, the daily liveweight gain in the post weaning period improved, from below 300 grams a day with the lightest pigs to in excess of500 grams a day for the heaviest piglets, during the 25 days post-weaning. This resulted in a difference in liveweight of over 13 kilograms in less than 7 weeks of life. The most efficient way of feeding the piglet to optimise weaning weight is to feed and water the sow correctly in order to maximise milk production. However, even when sows are milking well, milk intake and hence nutrient supply can vary from piglet-to-piglet depending upon which teat they suck (Hoy and Puppe 1992). This variation can be eliminated somewhat by the practice of creep feeding, which provides a direct supply of nutrients and acclimatises the piglet to solid food before weaning, so helping to optimise weaning weight and post-weaning performance.
Post-weaning gain in the first seven days post-weaning was increased from 180 grams per day to 240 grams per day as a result of increasing creep feed intake from 400 to 600 grams a day. Piglets that received creep feed prior to weaning, not only had increased weaning weights that directly led to betterpost-weaning performance. but also had inhanced post-weaning performance due to the enhanced development of their digestive system. Piglets that have had experience of creep feed are not so challenged by the process of weaning. They are familiar with the smell and taste of the postweaning diet and have better development of the enzymes needed to digest solid food.
3. Practical appllication of nutrition concepts
3.1. Immaturity of the digestive function
The ear1ier the pigs are weaned the more the alternative feed should emulate the composition of sows milk. The 20% of solids in sows milk is made up roughly of 8% fat, 6% protein, 5% lactose, 1% minerals and other components, and is completely digestible. Each piglet commonly received around 1000 grams of milk/day (approx. 200 grams of milk solids) and converts this at betterthan 1.1. So the suckling pig is attuned to utilising milk fat and lactose for energy and milk proteins for its amino acid supply.
3.2. Marginal acid secretion
The gastric acid secretion of piglets is at best marginal and in the presence of thigh acid binding feed stuffs can prove inadequate. In this situation gastric pH rises, the pH barrier to indigested bacteria (especially E. Coli) is relaxed, the activation of pepsinogen to pepsin is compromised and the digestive efficiency is impaired allowing more undigested material to flow to the lower gut. This combination results in bacterial proliferation, diarrhoea, dehydration, enterotoxaemia and possibly death. By providing supplementary organic acids via the feed or water the gastric pH barrier is maintained, digestion is more complete.
3.3. Feed intake
When we consider that sow’s milk has a digestible energy value of around 25MJ/kg dry matter, is provided in frequent (hourly) small serves and is rapidly digested, it is not difficult to understand why the shift to dry feed post weaning results in net reduction in nutrient intake. The key to the successful transition to post weaning diets is the combination of high nutrient density, high digestibility and factors that promote intake (e.g. Palatability, physical form of the feed, frequent feeding, prior experience of feed, familiarity with the drinker nipples, minimal stress, etc.) Material which are digested quickly and completely move out of the gut quicker than materials of lower digestibility and this helps to overcome the volumetric ingestive limits of the pigs stomach.There is good evidence to suggest that exposure to solid feed
4. The cost of the diet
This is important to appreciate because there is an investment to consider when we put together management and nutrition programs in the postweaning period. In order to maximise post-weaning gain, high quality diets have to be used. These are never the cheapest feeds but in the lifetime of the pig they are the most cost effective. If we consider that only a very small percentage, of the total feed consumed in a pig’s lifetime is eaten in the immediate post-weaning period, but this can affect
5. Modern diets
Todays diets offer extremely well balanced, palatable feeds. New words like iso- energetic, iso-nitrogenous, milk and whey powders, pre- and probiotics, plasma proteins, starch gelatinisation, palatants, extrusion, micronisation, expansion, fractionated fibres and acid oils are all terms used for products that make up the modern diet. An enormous amount of time and research has gone into the new Meadow pig feeds.
In summary the successful weaning process offers the producer a “window of opportunity” to really add value to the lifetime performance of the pig. He should concentrate on: Weaning pigs as heavy as possible within his production unit – this entails feeding and watering the sow correctly and improving on pre-weaning creep intakes.
The first 5 days in the weanerpool (this always occurs over the weekend). Temperature control, feed quality, supply and intake and management are paramount.
Continuously monitoring and checking and benchmarking and seeking ways to improve. Evaluating diets in a scientific manner and remembering the added advantages of additional early improved mass for down the track performance.
Feeding the piglet during the suckling and immediate post-weaning period. Gary Arnold, Meadow Feeds In house publication, August 2003.
Swine News, Nolth Carolina Coop Extention Service, February 2003
Weaner Nutrition Review, A C Edwards. Pig Production p 153-155 Proceedings 28517-21 February 1997
Recent advances in the feeding and nutrition of the piglet. Variey and Cole, SCA Nutrition
Date published: 2004-02-01
Dr PJ Grimbeek