Good feed is essential for animal growth, health maintenance and the production of good quality meat. For this reason, farmers should aware of appropriate feed stocks for pigs. An important factor often ignored is the types of food that pigs should not feed on. In fact, a popular assumption is that have dietary plans that are similar to humans. This is however not the case. There are various food that pigs should not feed on despite their suitability for human diets. Pigs are not able to filter out toxins from food or indigestible materials. Instead, the toxins are kept as fat storage thereby allowing them to consume a surprisingly high level of toxins. With time, animal health is compromised. As important as it is to know what to feed pigs, it is just as important to know what not to feed pigs.

Wild Mushrooms

Pigs are well known for their ability to forage day and night, consuming a variety of materials including that which contains toxins. As such, it is essential for farmers to ensure that the pigsty is free from toxic materials such as wild mushrooms. Commercially grown mushrooms are generally safe for pigs. However, pigs should not feed on wild mushrooms such as the death cap as well as the parasol. These are highly toxic; they account for about 90% of death in some countries like Australia. In fact, a single mushrooms contains enough toxins to kill an adult. Pigs should not feed on these mushrooms despite being cooked. An important point to remember is that all parts of the mushroom are toxic. Onset symptoms often occur about 6 to 24 hours after consumption; sometimes it takes a few more hours for the effects to be visible. Symptoms may subside for 1 to 2 days giving a false impression of recovery. When this occurs, the liver is already damaged and death can occur days after. Veterinary medical assistance must therefore be sought soon after consumption.

Raw Potatoes

Potatoes contain natural toxins known as glycoalkaloids. These are found in high concentration in the green parts of a potato. The levels are usually low but higher levels are found in potato sprouts, and the peel of potatoes that tastes bitter. For this reason, pigs should not feed on raw potatoes. The amount of glycoalkaloids founds in raw potatoes depends on the variety and growing conditions. Potatoes are often exposed to a variety of herbicides during their entire growing season. To add on, these compounds are not destroyed by cooking. Pigs tend to develop severe stomach pains after consumption of raw potatoes. Though highly limited, cases of death due to poisoning have been reported. Furthermore, pigs should not feed on green potatoes as they contain solanine which destroys red blood cells and can cause diarrhoea and heart failure. The leaves and skin also contain toxic compounds. They have trypsin which is an inhibitor to digesting proteins. Other foods that pigs should not feed on when raw include tomatoes and most members of the nightshade family as they contain potentially harmful toxins. It is therefore advisable to make sure that pigs do not have access to raw potatoes.

Fruit Seeds

Pigs should not feed on apple and pear seeds as they contain a naturally occurring and potentially toxic substance called amygdalin which is a cyanogenic glycoside. This substance can release hydrogen cyanide in the stomach causing discomfort or illness. If seeds are consumed in excess, the effects can be fatal. Note that the severity of the effects depends on the size and age of the pig as well as the amount of feed ingested. As stated earlier, pigs have the ability to tolerate a large amount of toxins. None the less, if over-consumption of seeds occur and they are chewed up, the pigs are most likely to develop acute symptoms. This is because chewing eliminates chances of excretion. Since farmers cannot determine if pigs are to chew seeds, it is advisable to remove them prior to providing apple or pear feeds.

Parsnip

Pigs should not feed on parsnip, celery, celery roots and parsley as they contain a group of natural toxins known as furocoumarins. These are produced by plants as a protective measure against stress. The concentration of furocoumarins is usually highest in the peel or surface layer of the plant or around any damaged areas. Parsnip plants do not cause animal mortality but pigs can become ill. In most cases, consumption leads to photosensitivity which can cause severe burns on pigs who eat large amounts. As such, farmers are advised to cook the plant and remove damaged parts. Heat decreases the level of toxins hence the need for cooking prior to providing these plants as animal feed.

Shelled Nuts

Pigs should not feed on shelled nuts with the exception of unsalted peanuts. Other nuts pose a danger of damaging part of the gastrointestinal tract due to their hard shells. In addition, some raw nuts such as almonds contain cyanide which can build up to toxic levels affecting animal health. This often occurs when large amount of nuts are consumed. Note that store bought almonds are treated thus are not a threat. In addition, pigs should not feed on raw cashews. They contain an allergenic phenolic resin, anacardic acid. When consumed excessively, animal health can be compromised.

Meat

Most countries have banned the consumption of meat by pigs. This is due to the transmission of infectious diseases which in turn affect human health. Therefore, pigs should not feed on waste materials that contain raw meat. Consumption of prohibited feed has led to some devastating outbreaks throughout the world, for example the foot and mouth disease outbreak in South Africa (2000). Farmers are hence advised to ensure that pigs are not provided with any form of meat. Diseases that can be spread by feeding food waste containing meat and dairy products to pigs include:

  • Foot and Mouth Disease
  • African Swine Fever
  • Classical Swine Fever
  • Swine Vesicular Disease
  • Transmissible Gastroenteritis

Conclusion

Food poisoning is said to be among the leading causes of compromised animal health as well as low productivity. Dissimilar to popular assumptions that pigs can generally eat anything, some types of food are highly toxic and can even result in increased mortality. In fact, according to agricultural research, many farmers across the globe experience a reduction in pig population due to toxic compounds found in food. An important factor to keep in mind is that human and pig diets are not the same and pigs have increased nutritional demands in comparison. As such, it is recommended that farmers strictly adhere to the outlined feed recommendations about what pigs should and should not feed on.  In cases of food poisoning, a veterinary medical professional should be engaged as soon as possible.