This article is from ECHO Asia Note #25
[Ed (AB) note: Keith has practiced sustainable farming at the Aloha House Orphanage in Puerto Princesa for 15 years, producing nutritionally dense, farm-derived food that is consumed both at the orphanage and by local customers. Last May, I had the privilege of visiting Keith and his family at Aloha House, where the 2nd ECHO Asia Philippines Sustainable Food Production Workshop was held. I was impressed by what they are able to achieve in a small area, with very few off-farm inputs. Keith is continually generous and open in sharing his experience and knowledge with visitors and the broader ECHO network. In ECHO Asia Note 20, Keith shared about farm-generated fish feed. In this issue, Keith will share some basics for creating farm-generated hog feed.]
Farm-generated fertility contributes to more sustainable agricultural systems. Crop residues and manures are part of the nutrient cycle and can lower input costs through the use of thermophilic composting, vermiculture, bokashi production, or green manures. Farm-generated feeds can also reduce expenses if farmers manage and utilize resources already available to them. For example, farmers might develop pasture using planned grazing for cattle; make hog feed from crop residue or dairy by-products (such as whey and skim milk); cultivate legume shrubs for cut-and-carry operations; and grow floating ferns and other water crops as feed supplements.
As densities of livestock increase, an industrious farmer finds ways and means to increase his farm’s nutrient stream for the benefit of his system. This article will describe methods and techniques necessary for a
smallholder farmer to succeed with farm-derived hog feeds. As you read, remember that a farmer should first fully exploit the extensive (and more passive) existing systems on the farm, and only then consider intensifying their overall operation (Figure 1).
[Author’s Note: It is important to note that many journals, papers, and guides caution against the tendency to abandon established methods of feed production for a more intensive system, without first assessing and then establishing new technologies with a transition period that is wellplanned, capitalized, and realistic.]
Overview of the Aloha System
As we plan feed regimens for our pigs, we secure both on-farm and off-farm feed sources, in case of contingencies. This is important, but often overlooked. The advice from Skillicorn is noteworthy: “Most farmers do not maintain all the ingredients needed to prepare a complete feed on-site or the equipment to blend and pellet it. They must, therefore, have guaranteed primary and alternative market sources at all times, which is not a simple management activity” (Skillicorn, 1993). At the Aloha House, we purchase our fishmeal, rice bran, and copra meal from local sources. We also have a wide variety of legume shrubs, trees, and floating ferns to supplement any shortfalls in our purchased protein supply.
Our experience is with Landrace, Duroc, and Large White varieties, as well as other modern domestic breeds and crosses that respond well to intensive feed operations. These breeds experience consistent, rapid growth with our fermented feeds. Large White, Duroc and Land Race pigs are readily available from commercial growers and reliable back yard breeders, and they convert well to our system.
In our area of Palawan in the Philippines, native swine are an alternative to modern breeds. They are most economically raised on pasture with planted forage crops and tubers. In a pasture system, the primary challenges with these wild swine breeds are keeping them healthy and keeping them fenced affordably. Their powerful snout and rooting skills enable them to escape if they are not properly fenced. Rather than being pastured, local pigs are typically tethered. They often compete for table
scraps with pets, tend to be stunted with poor growth, and can also be stressed by parasites (Figure 2). Internationally, basic established guidelines exist for swine raised in dirt lots, and tethering is not recommended. The University of Florida recommends 25 square meters per native swine (Meyer, 1993).
In the Philippines, both the Negros Warty Pig (Sus cebifrons negrinus) and the Palawan Bearded Pig (Sus ahoenobarbus) have been crossed with modern breeds with some success, but documentation of feed conversion and weight gain is hard to come by. Wild boar farmers in the UK cross pure wild boar males with domestic pig sows (usually Tamworths) to produce an increase in litter size, from an average of 5 in fully wild animals to 9 in hybrids. Hybrid vigor will contribute to better feed conversion, and hybrid pigs may benefit from fermented feeds. However, even with better feed conversion, increased costs may not justify the added carcass weight.
The remainder of this article will discuss methods for and benefits of lowering feed costs for modern pig breeds that tend to gain weight quickly and that are kept in a managed environment on cement or sawdust bedding. At the Aloha House, we have been using the “no-wash” happy pig protocol, as promoted through various Natural Farming networks. A complete description of the system is discussed in my book A Natural Farming System for Sustainable Agriculture in the Tropics. In this system, hogs are kept on a 1-meter deep sawdust bed and EM is added to the feed and water daily and sprayed weekly on bedding. Even sows enjoy farrowing on the deep beds and fermented feeds (Figures 3 & 4).
Many quality feed ingredients are available in most countries. Make sure you locate the best quality possible. Also, note that many feed programs in the industrial paradigm are not viable or profitable in developing countries!
Choosing High-Quality Inputs
Corn-fed pork is a phenomenon that came about through a glut of low-cost maize production in industrialized countries. Modern corn has a higher carbohydrate level and a corresponding lower level of protein. By contrast, rice bran has twice the crude protein of corn, and is often less expensive. In a natural feed system, protein is the number one limiting factor in performance and growth of livestock; it is also the most expensive to purchase. If you keep the target protein level appropriate for the age of the animal, everything else will balance out with your natural feed. In creating your pig feed, you pay for protein. Old corn-based feed formulas are based on corn varieties that had more protein than the modern dent corn that permeates our supply chain (which also contains glyphosate residues and is often genetically modified). On Palawan, where Aloha House is located, corn is approximately twice the price and contains half the protein of rice bran, making corn protein four times more expensive than rice protein. We want natural feed supplies for our hogs to be economical and to assure the best end product.
Unique Uses of Crops and Crop Residues Around the World
Innovative feeding solutions are found in various countries. Peanut tops, corn stalks, cabbage waste, and banana stalks are examples of useful
agricultural byproducts used in the Philippines for hog feed production. Dried cassava is also used in Mindanao and Luzon islands. In Palawan, the large singular leaf of a wild aroid called Amorphophallus paeoniifolius is harvested from the understory of wetland forests and sliced or chopped for feed (Figure 5). In India, varieties of these aroids (called elephant foot yams) are grown for their edible tubers.
In Thailand, banana stalks are fermented for pig feed. Fresh sliced or shredded banana stalks are mixed with sugar and rock salt (at a ratio of 100 kg chopped stalks : 4 kg sugar : 1 kg rock salt) and fermented for three days in a bucket. Various naturally-occurring cultured microorganisms are added to enhance the fermentation process. After three days, the fermented produce is mixed with an equal amount by weight of high-protein brans and fish meal (Tancho, 2015). [Eds.’ Note: For further reference and details on these natural farming pig feed recipes, please see Dr. Arnat Tancho’s “Natural Farming” and “Natural Farming Cartoon” books, which are available in English, Thai, and Khmer at the ECHO Asia Office.]
In Kenya, sweet potato vines are a valuable byproduct for livestock. Vines are chopped and fermented with EM1. Additional corn meal and protein are added to enhance performance (The Organic Farmer, 2015).
Cut and Carry Legumes and Grasses
Grasses can be an important forage source for animals. According to Dr. Martin “about 75% of forage consumed in the tropics is grass” (Martin, 1993). At the Aloha House, we grow a biodiverse spectrum of fodder crops that we bring to our hogs as cut and carry (Figure 6; Table 1). Compared to rooting livestock, people are better able to harvest carefully and leave plants intact. We grow Chrysopogon zizanioides (Vetiver) for slope stabilization and swale management in our water harvesting system. We also use it as a forage; we can harvest the young Vetiver with some frequency during the rainy season and maintain forage nutritional value. We have also utilized fresh cut Pennisetum purpureum (Napier) as a forage for hogs and cattle.
At the Aloha House, we have utilized the Sloping Agricultural Land Technology (SALT) system since 2001. This system uses legume tree and shrub perennials to stabilize soil along hillside contours, also incorporating annual alley crops. The fermentable legumes are important sources of protein and vitamins, as well as enzymes that boost feed digestibility (Watson, 1985). Over the years, we have been able to save seed from these prolific producers and expand from our starting stocks. We have established stands and contours of Desmodium rensonii (Local name: Ticktrefoil), Flemingia congesta (Malabalatong), Indigofera, Gliricidia sepium (Kakawate or Madre de Cacao), Leucaena leucocephala (Ipil-Ipil), and Mangium acacia. All of these legume species are valuable for fermented feeds (Agroforestry.org, 2008).
Crop residues can be used to lower feed costs. At Aloha House, legumes such as peanut tops, Gliricidia sepium, Leucaena leucocephala, Flemingia congesta, Desmodium rensonii, and Pueraria lobata (Kudzu) have been used successfully. Moringa and floating ferns are also used. Within the Korean Natural Farming (KNF) network, certain additives are avoided in hog feed due to alleged detrimental effects. We apply the KNF hog system at Aloha House, and therefore do not use bean vines or cassava leaves because of reports of bad side effects. The side effects are not well documented, but we avoid these as a precaution, and we have many alternatives. The protocol for introducing a new ingredient in a formula is to go slow and add one new ingredient at a time, to be able to tell which ingredient is having what effect. Be on guard for ill effects. Track weight gain and compare with normal growth. If scouring (diarrhea) occurs, remove the experimental ingredient and return to proven feed components.
Sourcing Mill Byproducts
To create a successful feed mix for your pigs, you must properly source high quality inputs, most often from local mills. “D1” rice bran (explained in more detail below) is considered the premium grade for livestock. Other lesser grades (D2 to D4) should be avoided, because protein content is lower and the percent of indigestible fibers (i.e. cellulose) is higher. See the Rice Mill Primer in the notes section of my book for more information (Mikkelson, 2005). Other brans (corn, wheat, etc.) can be used, but beware of compromising crude protein levels. Top quality rice bran is 12% to 14% crude protein, while most modern corn varieties contain only half this amount of crude protein.
Copra meal is the by-product of coconut fat extraction and can be obtained at oil mills. Copra meal contains up to 24% crude protein, but it should be limited to 10% of your formula by weight. It contains good quality protein but also a high amount of fat (similar to Black Soldier Fly larvae). Too much fat in the diet can cause scouring (diarrhea), and it will also sacrifice weight gain by reducing consumption of carbohydrates and protein. Copra meal is still worth including in our formula at 10% maximum by weight, because in our area it has a favorable price point. Fermentation (discussed below) further boosts digestible protein of copra meal. If copra meal is not available, increase the amount of fish meal used.
Rice Mill Challenges
Large Cono Mills are able to produce highly polished rice (often labeled
“WMR” for Well Milled Rice), leaving a waste byproduct that is valuable for feed formulation (Figure 7). Compared with other rice byproducts, this D1 rice bran has the highest vitamin, mineral and protein content. In many areas, only small mills (sometimes called “Satake Mills”) are available. These mills do not highly polish their rice, and may label it “RMR” (Regular Milled Rice). Satake Mills produce only D2 rice bran; it is inferior to D1 bran, but can be used in the Aloha House formula if it is supplemented at an increased rate of 25% more fishmeal than the basic formula by weight.
Many floating ferns and aquatic plants are high in protein. Aquatic plants can grow well in ponds that have adequate fertility to support them. They can be utilized for hog feed and are excellent as a cost-saving supplement when expensive purchased feeds are used. Floating ferns such as Azolla spp., duckweed (various genera and species), and even Salvinia spp. can be utilized if they are cultured and harvested efficiently. Omnivores such as swine and poultry readily eat large quantities of these greens as a feed source. Options for production include separate dedicated ponds, containers or troughs, and net-protected rafts within the fish culture. Remember, any fodder crops grown within the fishpond
must be protected or isolated from the fish; otherwise the fish will overgraze and deplete the crop (Figure 8)! In addition, if one goal of the pond is algae production, plants growing on the surface will block sunlight and prevent growth of algae and other phytoplankton. It is difficult to produce both protein sources (i.e. algae and water plants) to their full potential in the same column of water.
In experimental trials in India that compared Lemna minor (common duckweed), Ipomoea reptans (kang kong or morning glory), Trapa natans (water caltrap), and Salvinia cucullata (often mistaken for Azolla), both duckweed and morning glory had good feed conversion ratios and high protein: 28% and 32% respectively. (Kalita, 2007). Both of these can be great fodder crops. Azolla (Azolla caroliniana), with a reported protein range of 19-30%, is another fast-growing floating fern that I wish had been included in the India study.
Be careful not to overharvest these crops, or production will not be sustainable. As a general rule of thumb (under ideal conditions), you should harvest no more than half of the floating biomass per week (or 1/7 of the total biomass per day). The trick is to keep the plant in the rapid vegetative stage, so you will have to monitor which method of harvest is more productive in your system. Azolla tolerates moving water better than duckweed. Salvinia grows the fastest, but can be very invasive.
If you seek to intensify hog production, use of concentrated feeds is worth considering. However, commercial feeds are very expensive. The ECHO Technical Note on fish farming (Murnyak, 2010) lists a variety of supplemental feeds that are commonly used: rice bran, mill sweepings, termites, table scraps, maize bran, and many green leaves (Murnyak, 2010). Pelletized feeds are not necessary, despite marketers that portray pellets as more “modern” or “scientific.” The added cost of management and labor to make pelletized feeds outweigh the gains in growth. Hogs will readily consume a mash or crumbled fermented feed with great interest.
Documented Problems with Soy and GMO Crops
Aloha House is a soybean-free operation due to the detrimental health effects of soy. The phytoestrogens and enzyme inhibitors of soy are problematic for both livestock and humans. Concerns documented with soy include the following:
• High levels of phytic acid in soy reduce a body’s assimilation of calcium, magnesium, copper, iron, and zinc. Phytic acid in soy is not neutralized by traditional preparation methods such as soaking, sprouting, and long, slow cooking. Diets high in phytic acid have caused growth problems in children.
• Trypsin inhibitors in soy interfere with protein digestion and may cause pancreatic disorders. In test animals, consumption of soy containing trypsin inhibitors resulted in stunted growth.
• Soy phytoestrogens (i.e. plant estrogens) disrupt endocrine function, and can potentially cause infertility and promote breast cancer in adult women.
• Soy phytoestrogens are potent anti-thyroid agents that cause hypothyroidism and may cause thyroid cancer. In infants, consumption of soy formula has been linked to autoimmune thyroid disease.
• Vitamin B12 analogs in soy are not absorbed, and actually increase the body’s requirement for B12.
[Eds.’ Note: See the “Soy References Cited” section for more information.]
GMOs (genetically modified organisms) are also potentially problematic. A recent study linked cancer in hogs to their consumption of GMO soy and maize (Carman, n.d.). With so many other crops to choose from, we have chosen to avoid GMOs at the Aloha House.
On-Farm Production of Hog Feed & Formulas
With experimentation and careful recordkeeping, hog farmers can produce their own high-quality feed. In many countries, farmers can purchase readily available ingredients for production of cost-saving feeds. However, farm-generated ingredients make hog feed even more economical! At Aloha House, two people can produce 200 kg of moist feed in less than an hour.
Benefits of Fermentation The fermenting activity of certain beneficial microorganisms during the production process can enhance digestibility and shelf life of hog feeds. According to one study, the use of microorganisms increased the crude protein in copra meal from 17.24% to 31.22%. The amino acid profile was also found to be greatly improved (Cruz, 1997).
[Author’s Note: In addition to hog feed, at Aloha House we also ferment our feed for chickens, ducks, and fish with the help of diverse probiotic groups of microbes. However, we do not use fermentation for our ruminant feeds (this will be covered in another upcoming AN).]
When fermenting your feed, be sure to use proven strains that are not cross-contaminated with wild pathogens. We use EM-1, a commercial product that undergoes laboratory testing and is approved for livestock and aquaculture by the Department of Agriculture and by the Bureau of Fisheries and Aquatic Resources in the Philippines. EM-1 was formulated by Dr. Teruo Higa in Ryukyus University, Okinawa, Japan, and is readily available in over 100 countries. Thailand now consumes more EM-1 than Japan.
EM-1 contains cultures of robust lactobacilli, photosynthetic bacteria, beneficial yeast, and more. The microorganisms feed on sugars and other carbohydrates, while creating secondary metabolites that increase the nutrient range of the feed. The probiotic value is very high. My book, A Natural Farming System for Sustainable Agriculture in the Tropics, is a user’s guide to EM technology. It is available online as a free PDF download or can be obtained through the ECHO bookstore.
If EM-1 is not available, try using cheese whey or yogurt whey, sourced from a local creamery. Start small by substituting the whey at the same rate as EM-1 in the formula below, and add more in subsequent batches if it did not have an effect. Good fermentation should create a sweet and sour smell after two weeks. If foul odors such as rotten eggs (sulfides) or black molds occur, do not feed it to your hogs. Instead, add your small failed experimental batch to the compost heap and use it as fertilizer.
Another alternative to EM-1 is to use indigenous microorganisms (IMOs). In the KNF (Korean Natural Farming) system, “materials are mixed with sugar, salt, and IMO solution.” [Eds.’ Note: For more information on the creation and use of IMOs, please see the presentation “An Introduction to Asian Natural Farming” on ECHOcommunity.org.]
Table 2 below is a good recipe starting point for creating your own feed. Be sure to keep notes and adjust the ingredients based on your available feedstock and the performance of your farm-made feeds! Costs listed are relevant for our location and might differ elsewhere.
Mixing Sequence and Moisture Content
Make sure you have a clean, smooth concrete surface for mixing your feeds. When we ferment hog feed, first we pre-mix all our dry materials (rice bran, copra meal, etc.). Then we mix in the greens (e.g. salvinia, azolla, and legumes) and crop residues, so that the dry material coats the moist greens. Next we add 100 ml. each of EM-1 and molasses, diluted in 10 liters of water. We want the moisture content of the mixture to be between 30 and 50%; you may need to add additional water to reach this target moisture range.
A simple field test for moisture content in the 30-50% range is the “Ball Test.” Take a portion of the feed in two hands and form a ball with mild pressure. If it sticks together without dripping, it is in the target range. Congratulations! If the ball does not stick together, the mixture is too dry. Carefully add water a little at a time and test again. If it is dripping wet, it is over the moisture target range and you need to add additional formula-balanced dry materials to lessen moisture. Do not just add rice bran as a drying agent because you will compromise the recipe and it will not perform well.
After completely mixing all ingredients to 30-50% moisture content, we compress it in airtight pails and ferment for two weeks (Figure 9). This will ensure more uniform moisture content of the materials and achieve a better end product than a fresh feed mix.
Formulas for Modern Hogs
When creating your feed, be sure to measure and weigh each component accurately and record the performance of each trial mix. Keep some of your hogs on the current feed system (as an experimental control) so you have something with which to compare. After one month, compare the weight of hogs with your new feed and with the control.
We encourage you to use ingredients that are available in your area. Learn to optimize your own blend based on regular testing. A spreadsheet is useful for adjusting inputs and formulating feeds. After many months of record keeping, you will be able to evaluate the benefits of your farm-generated feeds. Crude protein is a good starting point; we find that if we formulate our mix based on crude protein, the rest takes care of itself.
Earlier I discussed floating ferns and their use as a fresh feed or for fermenting. Floating ferns are good for biodiversity and can create a broader range of inputs. You can use a combination of duckweed, azolla, and salvinia as a component of your low-cost, high-quality hog feed. Learn to culture these ingredients. Purchasing them is very expensive! Spirulina (a cyanobacterium, also known as blue-green algae) is a possible alternative to floating ferns. Over 30% of worldwide spirulina production goes to non-human feed stuffs (Belay, 1996). Other substitutions have been explored with mixed results, including water hyacinth in Nigeria (Igbinosun, 1988). I have not experimented with water hyacinth and would not recommend it due to its poor results in this study, but if you do, please send us your results!
Vitamins and Minerals
Finely crushed rock powder from gravel mills will have a range of minerals to supplement any deficiencies in cut greens or floating ferns (Murnyak, 2010). If we do not have rock powder, we add our organically grown moringa at 1% by weight of the mixture. Finely ground livestock-grade limestone from an agricultural supplier of feed store can also be added for bone growth support and lactating sows.
Hog Feeding Schedule and Protein Adjustments
Protein is the expensive part of an intensive feed operation, and you
should not use more than you need. If fresh greens are not used as cut and carry, then follow a protein reduction schedule based on the developmental stage of the hog in order to use less of the more expensive feed (Table 4). We follow well-established swine nutrition guidelines from the University of Missouri (Rea, 1993). Hogs need different amounts of protein depending on their stage of growth. To minimize costs, be sure to remove your most expensive protein as levels are adjusted. In our case, fishmeal costs the most and is what we would reduce based on our animals’ developmental requirements. Starter feed (Table 2) is used from weaning
to 18 kg, and contains 18% protein (Table 3). This high protein feed prevents stunting in the early stages. Protein is reduced to 16% for hogs in the “Grower Stage” (18-50 kg); we reduce fishmeal by three kg in this stage. To further economize production, hogs in the “Finishing Stage” (50 kg. to harvest) require only 14% crude protein. Finisher feed can be adjusted by reducing fishmeal by two more kg in our formula. All other ingredients remain the same. Greater savings and better animal health can be obtained with on-farm production of fermented hog feed, compared to commercial feed (Table 2).
At Aloha House we choose to maintain the starter ration throughout the life of our hogs and reduce overall protein by increasing the amount of vegetative feed that we offer. Figure 11 outlines the schedule for developmental stages of swine used on our farm. Weaners do not participate in cut and carry. As hogs mature, they are fed more “free food” from the farm in the form of crop residue and cut and carry.
Small-scale hog feed production can be managed by the careful use of locally grown and farm-generated inputs. Planning production two weeks in advance will assure a steady supply of nutritious fermented feeds. If you supply yourself with high quality inputs through efficient production and harvesting, and produce your own feeds, you will have more profits due to less capital input.
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