Feed and Nutrition Across Every Stage

Feed is typically 60 to 70 percent of the total cost of producing a pig. Everything else you do, housing, breeding, health, matters mainly through its effect on feed use. So the first skill in nutrition is arithmetic, not chemistry.

Feed conversion ratio

FCR is kilograms of feed eaten divided by kilograms of live weight gained.

FCR = feed eaten (kg) / weight gain (kg)

Example method: a pig goes from 20 kg to 90 kg, gaining 70 kg. Over that period it ate 210 kg of feed. FCR = 210 / 70 = 3.0.

Lower is better. Well managed commercial units on balanced feed commonly achieve FCR in the region of 2.5 to 3.5 from weaning to slaughter. Smallholder systems using a lot of unbalanced local feed often run 4.0 to 5.0 or higher, which is the real reason those pigs take so long to finish.

Feed cost per kilogram of gain

This is the number that actually decides which feed to buy.

Feed cost per kg gain = feed price per kg x FCR

A cheaper bag with a worse FCR often costs more per kilogram of pork produced. That is why bag price alone misleads people constantly. Work it out with your own currency and your own prices, both feeds side by side.

The comparison procedure

1. Get the price per kilogram of each feed, not per bag. Divide the bag price by the bag weight, and check the bag weight, because it varies.
2. Run each feed on a pen of similar pigs for a set period. Weigh the pigs in and out. Weigh or count the feed used.
3. Calculate FCR for each.
4. Multiply each FCR by its own price per kilogram.
5. Compare the two feed costs per kilogram of gain. The lower one wins, whatever the bag price says.

Days to market matter too

A feed that grows pigs faster also frees the pen sooner and cuts the fixed costs, labour and risk carried per pig. If two feeds cost the same per kilogram of gain, take the faster one.

Build your own price survey

Never take a number from a course, a website or a neighbour as your price. Prices for maize, soya, concentrate, bran and brewers waste move month by month and differ hugely between towns.

1. List every ingredient and every finished feed you might buy.
2. Phone at least three suppliers for each: a large feed company or its agent, a local mill, and a farmer or cooperative that sells surplus.
3. For each, write down: price, unit and true weight, moisture or wetness if it is a by product, minimum order, transport cost to your gate, and availability next month.
4. Convert everything to price per kilogram, delivered, on a dry basis where the ingredient is wet.
5. Repeat monthly. Keep it in one book or one sheet with dates.

Transport is often the difference between a bargain and a loss. Cheap wet brewers grains 40 km away can cost more delivered than a bag of balanced feed from the shop in town.

Wastage is invisible cost

Feed spilled from an overfilled trough, blown out of an open bag, eaten by rats or spoiled by damp is feed you paid for and never converted. Check for: troughs that pigs can root feed out of, bags stored on the floor against a wall, holes in the store, no lid on the mixing drum. Reducing wastage improves your effective FCR without changing anything about the diet.

Every bag of manufactured feed should carry a label or tag. Most farmers look only at the name on the front. The information that decides whether the feed will work is on the tag.

What the tag should tell you

• Product name and stage. Pig creep or starter, weaner, grower, finisher, sow gestation, sow lactation. Feed named for the wrong species or stage is the most common and most expensive mistake. Poultry feed is not pig feed.
• Complete feed or concentrate. This matters enormously. A complete feed is fed as it is. A concentrate must be mixed with your own energy source, usually maize meal, at a stated ratio. Feeding a concentrate straight will harm pigs and waste money. Feeding a complete feed diluted with maize will starve them of protein.
• Crude protein, minimum percent. The headline figure, but only part of the story. See the next lesson on lysine.
• Crude fibre, maximum percent. High fibre in a young pig feed is a warning. Young pigs cannot digest it.
• Crude fat or oil, minimum percent. Energy.
• Moisture, maximum percent. Feed sold wet is feed sold with water in it. Higher moisture also means shorter shelf life.
• Calcium, phosphorus and salt. Structural minerals and electrolytes.
• Lysine, and ideally methionine and threonine. Good manufacturers state lysine. Its absence is not proof of bad feed, but its presence is a good sign.
• Ingredient list. Some labels list ingredients, some list only categories. Ask.
• Medication or additives. If a feed contains a medicinal additive, the tag must say so and state a withdrawal period before slaughter. Read it, follow it, and record it.
• Manufacture or expiry date and batch number. Vitamins degrade with time and heat. A feed sitting in a hot store for months is not the feed on the label.
• Manufacturer name and address. Unlabelled feed from an unknown source is a gamble with your whole herd.

Reading it against your stage

Take the tag and ask three questions in order.

1. Is it for pigs, and for this stage? If not, stop.
2. Is it complete or a concentrate, and what is the mixing ratio? Get this in writing on the tag or from the manufacturer, not from the shop assistant's memory.
3. Do the protein and fibre figures fit the stage? Broad expectations are covered in Lesson 3. A weaner feed with a low protein figure and a high fibre figure is not a weaner feed regardless of the name printed on it.

Check the physical feed, not only the paper

• Smell. Fresh feed smells of grain. Musty, sour or paint like smells mean mould or rancid fat. Reject it.
• Look. Caking, lumps, visible mould, insects, or a dusty grey bloom are all rejection reasons.
• Feel. Feed should feel dry and run through your fingers. Damp feed spoils fast.
• Consistency between bags. Big colour or texture differences between bags of the same product suggest poor mixing or a substituted batch.

Questions to ask the seller

• What is the guaranteed lysine level of this feed?
• Is this a complete feed or a concentrate, and at what inclusion rate?
• When was it manufactured, and how long has it been in your store?
• Has the formulation changed since my last purchase? Formulations change with ingredient prices, and a change can explain a sudden drop in growth.
• Does it contain any medicinal additive, and what is the withdrawal period?

Keep one tag from every batch you buy, stapled into your record book with the date. When growth suddenly changes, that file tells you what changed.

Crude protein on a label is a crude measure. It tells you roughly how much nitrogen is in the feed, not whether that protein contains the building blocks the pig actually needs.

The limiting amino acid

Pigs do not need protein as such. They need about ten essential amino acids that they cannot make themselves. Growth stops at whichever essential amino acid runs out first, no matter how much of the others are present. In cereal based pig diets, the first one to run out is almost always lysine. This is why lysine, not crude protein, is the real currency of a pig diet.

The practical consequences:

• A high protein feed made from poor sources can support less growth than a lower protein feed that is properly balanced for lysine.
• Excess protein above what the amino acid balance can use is not stored as growth. It is broken down, the nitrogen is excreted, and it costs you money and puts load on the gut and the kidneys.
• After lysine, the next limiting amino acids in typical diets are usually methionine, threonine and tryptophan.

Working ranges by stage

These are widely used ranges for balanced diets. Treat them as targets to check a feed against, not as precise formulation values, and remember that ingredient quality changes what the same percentage delivers.

Reading the pattern

Requirements fall as the pig grows. A young pig is laying down lean muscle fast on a small feed intake, so its diet must be nutrient dense. A finisher eats far more each day and is depositing more fat, so it needs a lower concentration. Feeding starter feed to finishers wastes expensive protein. Feeding finisher feed to weaners stunts them. Both mistakes are common on farms that buy one bag for everything.

The one bag trap

Buying a single grower feed for all pigs looks simpler and cheaper. In practice it under feeds the young pigs, where the return on good nutrition is highest, and over feeds the finishers, where protein is wasted. If you can only carry two feeds, carry a starter or weaner feed and a grower or finisher feed, and be strict about which pigs get which.

Sows are a special case

A gestating sow fed a grower diet gets too fat, which causes farrowing problems and poor appetite in lactation. A lactating sow fed a gestation diet cannot support milk production and strips her own body, which shows up later as a long wean to service interval and a smaller next litter. If there is one place to keep two separate sow diets, this is it.

Protein sources

Soyabean meal is the standard high quality plant protein and is well supplied with lysine, but raw soyabeans must be heat treated before feeding because raw beans contain factors that block protein digestion. Sunflower cake, cottonseed cake and groundnut cake are useful but lower in lysine and higher in fibre, so they cannot simply replace soya kilo for kilo. Fishmeal is excellent quality but expensive and often adulterated, so buy only from a source you trust. Where you use a commercial protein concentrate, follow the manufacturer's mixing ratio exactly.

Protein gets the attention, but energy is what a pig eats for. A pig eats to meet its energy need and stops when it is met, which is why the energy density of a feed controls how much of everything else the pig takes in.

Energy

• Main sources are cereal starch (maize, sorghum, wheat, cassava) and fats or oils.
• Fat carries more than twice the energy of starch per kilogram, so a small oil inclusion lifts density substantially. It also reduces dust. But fat goes rancid, so use fresh oil and do not store fatty feed for long in the heat.
• If energy density is low, the pig tries to eat more feed to compensate. If the feed is also bulky, it physically cannot, and growth slows. This is the mechanism behind slow growth on high bran diets.
• Cold pigs burn energy on heat instead of growth. Housing is a nutrition issue.

Fibre

Pigs are not ruminants. They have limited ability to extract energy from fibre, and that ability increases with age.

• Young pigs (creep, weaner): keep fibre low. High fibre reduces energy density and digestibility exactly when the pig needs the opposite. This is why heavy maize bran inclusion in weaner diets fails.
• Growers and finishers: tolerate moderate fibre. Some fibre supports gut health and firmer dung.
• Gestating sows: the one class that genuinely benefits from higher fibre. A gestating sow is fed a restricted amount to stop her getting fat, and she is hungry. Bulky fibrous feed such as vegetable forage, bran or well processed local greens fills her, keeps her calmer, and reduces stereotypic behaviour. This is where cheap fibrous local material earns its place on a smallholding.

Minerals

• Calcium and phosphorus build bone and must be in the right balance with each other, not just present. Too much calcium relative to phosphorus causes problems even when both are adequate. Much of the phosphorus in plant material is bound as phytate and poorly available to pigs, which is why commercial diets add mineral sources or the enzyme phytase.
• Salt is essential, commonly included around 0.4 to 0.5 percent of the diet. Do not overdo it, and never restrict water on a salted diet, because salt poisoning happens when water is limited.
• Trace minerals including zinc, copper, iodine, selenium and manganese are needed in small, precise amounts and are supplied through a premix. Home mixed diets without a premix will eventually show deficiency problems.
• Iron for suckling piglets is covered in Module 7 and is the one mineral you inject rather than feed.

Vitamins

Vitamins A, D, E and K plus the B group are supplied in premixes and in green forage. Two practical points: vitamins degrade with heat, light and time, so old feed stored in a hot shed is weaker than its label says; and pigs kept entirely indoors get no vitamin D from sunlight, so it must come from the diet.

Water - the forgotten nutrient

Water is the cheapest input and the one most often limiting. A pig short of water eats less, immediately.

• Rough daily intake guides: weaners a few litres a day rising with size; growers and finishers in the region of 5 to 10 litres; a lactating sow can drink 15 to 30 litres or more in hot weather.
• Flow rate matters as much as availability. A nipple that dribbles will not water a growing pig in the time it is prepared to stand there.
• Set drinkers at about shoulder height and raise them as pigs grow.
• Water must be clean enough that you would consider drinking it. Cover tanks, clean them, and check for algae.
• In hot weather, water is also cooling. Shade, wallows where appropriate, and plenty of drinking water prevent heat stress, which cuts feed intake and, in boars and sows, fertility.

Local ingredients are how smallholders survive high feed prices. Used well they cut cost. Used carelessly they slow growth, cause disease, and cost more per kilogram of pork than the bag you were avoiding.

Four questions to ask about any local feed

1. How much protein, and of what quality? Most cheap local ingredients are energy or bulk, not protein.
2. How much fibre? High fibre means low energy density and a limit on inclusion, especially for young pigs.
3. How wet is it? A wet by product priced per kilogram is partly priced water. Compare on a dry basis.
4. Can I get it consistently? An ingredient you can only get some weeks should be a small part of the diet, never the backbone.

Maize bran and milling by products

Cheap, available everywhere, and the most misused ingredient in the region. It is an energy and bulk source with modest protein, commonly around 8 to 11 percent crude protein, and relatively high fibre. Fine bran from a commercial mill differs a lot from the coarse husky sweepings sold at a village hammer mill, so inspect what you get.

• Do not build weaner or starter diets on bran. Fibre and low energy density are exactly wrong at that age.
• Moderate inclusion suits growers and finishers, and higher inclusion suits gestating sows where bulk is an advantage.
• Bran goes mouldy or rancid quickly because of its oil content. Buy fresh, store dry and off the floor, use within weeks.
• Bran plus greens is not a pig diet. It produces a slow, thin pig and a long feeding period.

Sweet potato vines and green forage

Vines, cassava leaves, amaranth, lucerne and similar greens are genuinely useful, particularly for gestating sows and to a lesser extent growers.

• Sweet potato vines carry useful protein on a dry matter basis, commonly reported in the region of 14 to 20 percent, but they are very wet and fibrous, so a pig fills up on water and fibre long before it gets much of that protein.
• Wilt them for a day in the shade and chop them before feeding. This cuts moisture, reduces bulk and improves intake.
• Cassava leaves and roots contain cyanogenic compounds and must be dried, chipped and sun dried, or soaked and fermented before feeding. Never feed fresh bitter cassava.
• Treat greens as a supplement and a vitamin and gut benefit, not as the protein source for growing pigs.
• Never cut forage from land recently spread with pig manure.

Brewers waste and distillers grains

Spent grain from commercial and local brewing is common and can be very good value.

• Wet spent grain is often around 70 to 80 percent water, so most of the weight you buy and transport is water. Always calculate cost per kilogram of dry matter before deciding it is cheap.
• On a dry matter basis it carries useful protein, commonly reported around 20 to 25 percent, with moderate to high fibre.
• It spoils very fast. In warm weather it can sour and mould within one to three days. Use it fresh, keep it covered and out of the sun, and never feed a load that smells sour or shows mould.
• Residues from local spirit distilling may contain alcohol. Do not feed these, particularly to pregnant sows.
• Introduce it gradually over about a week and keep the proportion stable. Sudden changes cause scour.

Other common local materials

• Market vegetable and fruit waste: acceptable if it is plant material only, fresh, and free of mould and packaging. It is watery, so it is a supplement.
• Oilseed cakes (sunflower, cotton, groundnut): real protein, but variable, fibrous and lower in lysine than soya. Cottonseed cake contains gossypol and must be limited, especially for young and breeding pigs. Groundnut cake is highly prone to aflatoxin.
• Raw soyabeans: heat treat before feeding.

Mixing at home

If you mix your own feed, buy a protein concentrate or a vitamin and mineral premix and follow its stated inclusion rate exactly. Mix the premix into a small quantity of meal first, then into the whole batch, until the colour is uniform. Mix only what you will use within a couple of weeks and store it dry, off the floor, away from rodents.

Some feeds are not a nutrition question at all. They are a survival question for your herd and your neighbours' herds.

Swill and kitchen waste

Swill means food waste containing or contaminated with meat or animal products: restaurant and hotel leftovers, kitchen scrapings, market meat waste, plate waste, waste from a butchery.

African swine fever is the reason this matters more in this region than almost anywhere else. ASF is a viral disease of pigs with very high mortality in domestic pigs, no widely available effective vaccine in most countries, and no treatment. It is endemic across much of sub Saharan Africa. Once it enters a herd, the usual outcome is that the herd is lost.

The virus is unusually tough. It survives for long periods in uncooked, chilled, frozen and cured pork products. A piece of pork from an infected pig, put in a bin, mixed into scraps and fed to pigs, is a proven route of introduction, and swill feeding is one of the main ways ASF has been carried into new areas and across borders worldwide.

The rule

Do not feed swill, kitchen waste, catering waste, plate waste or any material that has been in contact with meat. In many countries in the region this is not just advice, it is a legal prohibition. Find out the law where you farm.

If you take this rule seriously, it must be a rule for everyone, not just for you:

• Tell every worker and every family member. One person emptying a plate into the pig trough is enough.
• Keep the household kitchen bin physically away from the pig area.
• Never accept a donated bucket of hotel or restaurant waste, however cheap or free.
• Do not let pigs scavenge around cooking areas, market stalls or dumping sites.
• Do not feed dead pigs, pig offal, or dead animals of any kind to pigs. This is how disease is recycled.

Where heat treatment of catering waste is legally permitted in a particular country, it involves a controlled, monitored boiling process at prescribed temperatures and times in an approved facility, not a pot on a fire. For a smallholder, the practical answer is simply not to feed it.

Other ASF entry routes to close at the same time

• Visitors, traders and their boots, clothes and vehicles. Keep a boundary and a boot change.
• New pigs bought in without quarantine. Isolate new arrivals well away from the herd.
• Shared equipment, borrowed wheelbarrows and shared transport crates.
• Ticks in some settings, and contact with free ranging or wild pigs.

Mould and mycotoxins

Mouldy feed is the other thing you must refuse. Moulds growing on maize, groundnut cake, bran and stored feed produce mycotoxins, including aflatoxins, fumonisins and zearalenone. Pigs are among the most sensitive farm animals to several of these.

Effects seen include reduced feed intake and growth, liver damage, immune suppression so ordinary vaccines and defences work less well, abortions and reproductive failure, and in the case of zearalenone, swollen vulvas in young gilts and reproductive disruption in sows.

You cannot see or smell most mycotoxins reliably, and cooking does not destroy them. Prevention is the only practical control.

• Buy grain that is properly dried and store it dry. Moisture is what allows mould to grow.
• Store bags off the floor on pallets, away from walls, in a ventilated store with a sound roof.
• First in, first out. Do not let old stock sit at the back for months.
• Reject any delivery with caking, visible mould, a musty smell, or heating in the bag.
• Clean feeders and mixing equipment. Caked residue in a corner of a trough is where mould starts.
• Be especially careful with groundnut cake and with maize from a bad harvest year.
• Never feed obviously mouldy material to breeding animals, and do not feed it to any pig. Discarding a bag is cheaper than losing a pregnancy.

A short list of other things not to feed

• Raw soyabeans, untreated.
• Fresh bitter cassava or cassava leaves that have not been dried, soaked or fermented.
• Material contaminated with pesticide, treated seed dressed for planting, or fertiliser.
• Salt heavy waste with no free water available.
• Any feed of unknown origin in an unlabelled bag.