FEEDING NEWLY WEANED PIGS NON-MEDICATED FEEDS.

Martin Clunies. PhD. Swine Nutritionist.

Growing concerns about drug residues in meat products and the perceived risk of disease organisms resistant to in-feed antibiotics, has caused a great deal of debate concerning the use of growth promotants and medications in feeds used for livestock animals. With the safety concerns about our food source, there is the call for elimination of the use of non-therapuetic antibiotics in animal feeds. This call for reduction in medication is balanced on the other hand by the need to produce meat products efficiently, while reducing the risk of transmission of organisms, such as Salmonella sp. to human populations. This debate has pork producers investigating many alternatives to the traditional use of medicated feeds. The greatest concern in eliminating the use of medicated feeds throughout pork production systems are the risks associated with feeding newly weaned pigs such feeds. Young, newly weaned piglets by their naive immune systems are prone to disease lacking the antibodies to fight off infectious organisms.

One Ontario Pork producer family have become a pioneers in the feeding of newly weaned pigs non-medicated feeds. Peter and Jane Rombouts of Thedford are feeding non-medicated liquid feeds to their baby pigs immediately following weaning, approximately 21 days of age. It was back in October 1997, that Peter first began to investigate the possibility of feeding liquid feeds to nursery pigs. Initially this was in an attempt to reduce the lag in growth that occurred when pigs were transferred from dry feed in the nursery unit to liquid feeds in the growing/finishing unit. Peter first discussed the idea with Jerry Koert of JD Bettermix, Wartburg Ontario, who had installed the liquid feeding system for the growing/finishing unit at Peter's farm. After tossing ideas back and forth for a few months the system they decided upon used a liquid fermented feed to provide a nutrient rich broth for newly weaned pigs. Then in February 1998 it was off to the United Kingdom to see one of the systems in operation. The system was being used to feed baby pigs following weaning, and the producer seemed quite happy with the results. There were, however, some differences to what Peter and Jerry had planned. First, Peter would be weaning younger pigs, 18 - 24 days of age, compared to what he saw in the UK. Secondly, the UK producer was using the system with by-products as a way of reducing costs, while Peter planned to use corn and soybean meal as the basis for his feed. With everything they had seen and heard, the decision was made to purchase the equipment upon returning to Canada. The equipment arrived last summer and was installed in November 1998.

The principle of the system is based on fermenting two feeds in two separate vats. The feed from the first vat is fed immediately after weaning while the feed from the second vat is the last feed used in the nursery phase. The two feeds are then blended in various proportions to fit the stage of pig growth in the nursery. Each feed vat has its own dedicated feed line which blends the feeds at a valve above the feeder. The fermentation is done by lactic acid producing bacteria which use the feed to grow and produce acid. When the fermented feed broth is fed to pigs these lactic acid producing bacteria compete with other pathogenic bacteria for nutrients and sites of attachment in the digestive system. In addition they create an environment of low pH that pathogenic bacteria do not tolerate well.

The nursery unit comprises of 8 rooms, each with one large pen, which holds 80 pigs. Specialized feeders (one per room), imported by JD Bettermix, allow many pigs access to feed at the same time, much like the litter on a sow. The feed is provided by a computerized, self managed system which provides the pigs with frequent meals. The computer checks sensors installed on the feeders every 10 minutes from 5:30 am - 8:00pm. Between 8:00 pm - 5:30 am the feeders are checked at 10 minute intervals for 30 minutes with 1.5 hour rest intervals between. In this manner the system offers the pigs small amounts of feed at frequent intervals, much like a sow, and increases the feed as the pigs need. With such a high feeding frequency the system operates like one sow with many litters. The computerized system keeps a record of the feed consumption for the last two days and the total feed per pen. It does so for the proportion of each feed used.

Initially the feeds were dry blended from a commercial supplement which was mixed with corn and soybean meal on the farm. The resulting dry feed was then added to the respective vat for the fermentation process. Due to the fact that the feeds are fermented no medication could be added to the mixture as this would kill or significantly reduce the viability of the bacteria required for fermentation.

In order for the fermentation to result in a consistently, high quality feed broth many factors needed to be controlled. The first was to control the temperature in the vat so that the fermentation proceeded exactly as planned. The second was to control the rate at which feed is used and replaced in the vat, so as to avoid shock to the organisms fermenting the feed. The fermenting broth is regarded as a living unit and for optimum growth and quality control, conditions have to be kept as uniform as possible over time. A local plumber developed an energy efficient system for heating and maintaining an ideal water temperature for a more optimized fermentation to proceed rapidly. The fermentations vats are filled 3 times daily, and care is taken not to replace more than 25% of the vats contents at any one time. Replacing more than 25% of the contents reduces the rate of fermentation.

Initially the fermentation relied on the natural bacteria in the grain corn to ferment the feed, much like the natural yeasts of the grape providing the fermentative power for wine. However because of the variability associated with corn and the lack of ability to correct for that variation, the fermentation was not as controlled. At that time Peter and Jerry thought that Grand Valley Fortifiers, with their natural probiotic philosophy to feeding pigs, could provide technology of benefit to the fermentation system. Dr. Martin Clunies suggested that a high inclusion premix/supplement, which contained a probiotic, may be a way of ensuring that the fermentation was uniform from batch to batch. Also, with the temperature controls put in place, an enzyme with known pH and temperature optimums were added to predigest some components of the grain and soybean meal, improving their nutritional value. This latter technology allowed less costly ingredients to be used thereby significantly reducing the cost of the ration and improving the performance of the pigs. With the fermentation process so critical to the success of the feeding program, in-feed buffers were used to control the pH during the initial phase of fermentation following the introduction of dry feed to the vat. The levels of probiotics in the supplement/premixes initiated a good start to each batch fermentation following charging of the vat with dry feed.

With most of the problems of the feed seemingly solved Peter turned his attention to the management and flow of pigs through the nursery unit. Each week Peter weaned approximately 110 -120 pigs, between 18-24 days of age. With eighty pigs per room, there was a two week maximum fill time per room. During the initial phases of the project Peter had set aside one room a carry over for undersized pigs. As the problems related to feed were resolved and the number of under sized pigs reduced, the need for the flush room was eliminated. At the present, with the nursery sort size variation very low, all pigs are transferred to the growing/finishing unit where they are sorted into pens by size. Whereas before these smaller pigs did not do very well now, because they have been previously feed liquid feeds, they seem to do very well. As the management in the nursery unit was fine tuned, to streamlined the pig flow, the schedule of feeding each phase of feed was adjusted. As a result mortality was improved further. At present mortalities are very good, between 2 - 3 % in the nursery. Although the mortality is low, there is still the need to treat 2 - 4 pigs per pen with injectable medication for a number of ailments, which include respiratory problems, Strep. sius, swollen joints, etc. Possibly the some of best results have been achieved by carefully phasing the feed mixtures for the weight of pig at the beginning of the nursery phase. These final feed adjustments have eliminated all traces of scours and the performance of the pigs has been further improved. This was done through constant communication between Peter, Jerry and Martin who each viewed the process as a learning experience. At the present pigs Peter is moving 20 kg pigs to the grower/finisher unit after 35 days in the nursery, on a fairly consistent basis. With the information the system provided on feed intake along with monitoring pig weights decisions were easier to make, and changes subsequently evaluated for success.

While the initial results suggest the system has been successful, it will take a greater length of time to determine the overall success of this project. Certainly a number of advantages have been realized to date, and they may be summarized as follows:
• The use of in-feed medications have been eliminated in the nursery unit.
• The cost of feed and the cost of feeding the nursery pig have been significantly reduced.
• The original objective of reducing the lag in initial growth in the finishing unit has been accomplished. Already Peter sees less variation in the growth of the market pigs.


DAIRY

Maximizing CORN SILAGE QUALITY
by Mark Bowman, Grand Valley Dairy Nutritionist.

Corn silage quality is influenced by many variables, some that can be controlled by the dairy producer, and others that cannot. Decisions made several months ago regarding selection of silage hybrids, planting dates and planting densities will affect yield, starch content and NDF digestibility of the silage that is made this fall. At this point these choices have been made, right or wrong, and the results cannot be changed for this year. However, opportunities still exist at harvest time for producers to significantly influence corn silage quality.

This year, with the lack of sunshine and heat we will be challenged with corn silage that is low in starch and energy content because it may not mature before a killing frost. Within this context corn silage harvest decisions that affect quality include:

• Harvest at 30 – 35 percent dry matter. Due to the weather this year, getting corn silage dry enough may be a challenge. Corn harvested below 30% DM will not likely be mature enough and yields of starch and DM will be reduced. Wet corn silage may also reduce fermentation quality and feed intake. Corn that is too dry will be less digestible (both starch and NDF), resulting in less energy for milk production.

• Harvest at 1/3 – 2/3 milk line. Again due to the weather this year, corn may not mature enough before a killing frost. Yields of starch and DM will be reduced if harvested before this stage of maturity. Corn harvested beyond this maturity will have harder kernels and lower digestibility.

• Optimal chop length. Corn silage should be chopped at a theoretical length-of-cut of 1/2 - 3/4 inch, on the shorter side if not processed and on the longer side if it is processed. Optimizing the length of chop will result in better packing in the silo and effective fibre for the cows.

• Consider an increased cutting height. As cutting height increases the ratio of grain to stover in the silage increases, resulting in higher starch and energy content. The lower sections of the plant contain higher levels of ADF and NDF so that increasing the cutting height results in lower ADF and NDF as well as greater NDF digestibility. Increased cutting height reduces yield by approximately one tonne/acre per 6 inches. If one has enough forage supply, substantially raising the cutting height can help to increase the starch and lower the NDF closer to normal levels in corn silage that fails to mature adequately before a killing frost.

• Process corn silage if possible. When corn silage is 35% DM or higher processing will improve digestibility and milk production. Regardless of DM content it allows for longer chopping length and more uniform particle size to improve effective fibre content and reduce sorting.

• Use a silage inoculant. Silage inoculants will ensure more rapid and complete fermentation of silage by increasing lactic acid production and reducing silage pH. Research also shows that inoculants reduce DM losses by 2 – 3 percent, increase NDF digestibility, increase intake and result in more milk production.

• Packing and covering. Silage in bunker silos must be packed and covered properly to drive out air and keep it out. Higher packing density and sealing with plastic is strongly associated with reduced DM losses and improved feeding quality.

• Let the silage ferment before feeding. Changing the cows to fresh and fermenting silage can lead to digestive problems and reduced milk yield. Try to let the silage ferment at least 4 weeks before feeding. If not possible to do this year, plan ahead for next year to ensure that you can do this in the future.


Balancing Rations With New Corn Silage

There may be large differences in corn silage quality between the old crop and new crop, especially in a year with very different growing conditions than normal. This year we may anticipate corn silage with lower starch and energy content and higher NDF content due to the lack of sunshine and heat.

Sample and analyze your fermented silage to determine the nutrient content and feeding value. Silage changes during the fermentation process, so it is best to test fermented samples rather than fresh. A comprehensive corn silage assay should include DM, CP, ADF and NDF contents, as well as starch, sugar and mineral contents and calculated Net Energy Lactation content. For more accurate digestibility and energy estimates, digestible NDF may also be analyzed, using an In-vitro method.

Rations should be balanced for all groups of cows and heifers based on the nutrient content of the corn silage and other forages. Corn silage with lower starch and higher NDF content will result in rations with lower forage and higher grain contents to balance.

Adding Grand Valley Fortifiers bakery meal, a highly digestable source of starch and sugar, may help to increase milk yield with poor quality corn silage.

We at Grand Valley Fortifiers are your source for direct, to-the-farm Kaster bakery meal. Kaster bakery meal is a consistent, well-processed product, which can be delivered in 40 tonne truck loads or a minimum of 10 tonnes on a GVF delivery vehicle. Talk to your Dairy Specialist or call 1-800-567-4400 for more information and current pricing.

Optimize HM Corn Feeding Value

HM shelled corn or HM corn & cob meal are the major source of added grain and starch in many Ontario dairy rations. When harvested, stored and processed properly these are among the best quality and most economical energy sources available.

Stored in oxygen limiting bottom unloading silos, HM corn should be in the range of 22 to 30 percent moisture at harvest. For increased digestibility and milk production it should be ground with a hammer mill before feeding in a TMR. When top dressed rather than fed in a TMR HM corn should be rolled rather than ground.

HM corn or corn & cob stored in open tower silos or bunker silos should be harvested at 30 to 36 percent moisture for best results. HM corn and cob should be ground into meal and at this moisture content HM shelled corn should be rolled for best feeding value.

This year we may see HM corn that is low in starch and high in moisture content due to the growing conditions and this will lead to feeding challenges. HM corn that is too wet can more easily result in rumen acidosis, off feed and low fat test and lower starch content will result in less energy and milk. HM corn above 30% moisture should be rolled rather than ground to slow down starch digestion. The amount of very wet HM corn fed should be limited and replaced with dry corn if possible.