Goats are well known for their ability to pasture on anything from grass to scrubby woods, where they can eat young trees and shrubs. A common misconception is that goats can eat any form of grass and shrubs. As a matter of fact, goats should not feed on a variety of plants.  This is because they have a delicate immune system despite their ability to digest inedible feed. They can therefore become ill and die very quickly: a matter of hours can mean the difference between life and death. Note that although there are several plants that can be poisonous to goats, the severity of plant poisoning depends on the quantity of the plant that was eaten, the amount of ground moisture, the health of the animal prior to consuming the toxic plant, and the size and age of the animal that consumed the plant.

Avocado Plants

Avocados are highly famed form their nutritional value hence are an important part of human dietary plans. Despite their benefits to human health, goats should not feed on avocado plants. Avocados contain persin, a fungicidal substance and toxin that seeps into the flesh of avocados from its seeds. Goats are not able to tolerate persin present in avocados. This also applies to the leaves and trees of avocado trees. In fact, persin is found in high quantities in avocado trees and leaves, hence should be avoided. Goats should not feed on avocados as they develop non-infectious mastitis. The symptoms include gastrointestinal irritation, diarrhoea, respiratory distress, congestion and fluid accumulation around the tissues of the heart. When not handled appropriately and timeously, goats can even die. It is therefore recommended for farmers to make sure that grazing fields are free from avocado trees. If for some reason goats consume avocado leaves, a veterinary medical professional must be consulted.

Rhubarb Plants

Rhubarb leaves contain oxalic acid which is a toxic compound. As such, when consumed in large amount, animal health can be significantly compromised. The digestive system of a goat has the unique ability to breakdown toxic substances, converting them into less harmful compounds. However, despite their superior ability to tolerate toxic plants, goats should not feed on rhubarb leaves. Symptoms of rhubarb poisoning in goats include diarrhoea, depression, trembling, and drinking and urinating more frequently. When consumed excessively, rhubarb leaves can cause kidney failure and even death. Goats do not normally prefer rhubarb leaves to other plants. They often resort to rhubarb leaves when there is a shortage of food and if their nutrient proportions are unbalanced. Goats can also eat rhubarb leaves during drought periods or when pastures have been over grazed. For this reason, farmers should ensure that livestock are provided with appropriate feed, rich in essential nutrients and in proper quantities.

Nightshade Plants

Goats should not feed on plants belonging to the nightshade family. These are formally referred to as solonaceae. They include eggplants, tomatoes, peppers and potatoes. Tomato leaves, stems & blooms (uppers), green potato skins, and upper plant parts from nightshade plants all contain concentrations of toxic compounds referred to as alkaloids. The major toxin is solanine; along with other glycosides and atropine, these have numerous and powerful effects on animal health. Early symptoms are nausea, colic, diarrhoea, blindness, muscular weakness, confusion, overheating and vision issues which can head into convulsions. Some farmers have reported chronic cases whereby animals experience severe symptoms leading to death. As such, it is highly unadvisable for goas to feed on nightshade plants. Similar to most toxic feed, goats do not opt for such plants under ideal circumstances. In fact, most plants that belong to the nightshade family are not palatable and so are only eaten when there is shortage of feed. Although some nightshade plants are not as poisonous as others, various agricultural research have dismissed nightshade leaves as appropriate goat feed.

Rhododendron Plants

These can be toxic to goats even in small amounts. Rhododendron plants are among the leading causes of goat poisoning. Therefore, goats should not feed on these plants. The first signs of rhododendron poisoning include gastroenteric signs such as salivation, diarrhoea, colic, and bloat. Excess consumption causes additional signs which may include abnormal heart rate and rhythm, loss of coordination, and convulsions, followed by coma and death. Toxic dosages of rhododendron plants range between 0.1 to 0.2% body weights which equates to about 136g for a 68kg goat. Note that goats should not feed on any part of these plants, including leaves as they contain a higher amount of toxins. Goats do not readily eat rhododendron plants, however, they can may consume them while grazing hence the need for grazing areas to be inspected from time to time. If animals consume rhododendron plants, a veterinarian should be engaged as soon as possible.

Excess Grain

Goats should not feed on too much grain. Farmers usually assume that grains are suitable for animal feed despite the quantity. This is however not the case. The effects of grain overload include depressed appearance, diarrhoea, dehydration and thirst, bloating (of the left side of the abdomen), tender gait and ‘sawhorse’ stance or even death. Grain overload occurs when goats eat large amounts of grain, causing carbohydrates to be released in the rumen resulting in fermentation instead of normal digestion. Lactic acid is therefore produced resulting in the slowing down of the gut, dehydration, and in acute cases death. Grain overload is often experienced when goats graze in new pastures or when there is a sudden switch in their dietary plans to include grain feed.

Conclusion

Goats are naturally browsers and so toxic plans pose a real concern for farmers. Goats should not feed on plants that contain toxic elements or overfeed on grain.  The impact of animal poisoning may result in irreversible damage which has adverse effects on productivity. In severe cases, the damage continues to escalate such as in progressive liver or kidney disease eventually leading to death. A significant agricultural investment is therefore lost including veterinary bills, costs related to productivity: decreased weights for meat producers, loss of dairy production or milk quality, reproductive losses and deformities in new born calves among numerous others. Fortunately, with some knowledge, awareness, and effort, farmers are able to prevent goat poisoning. In simple terms, goats should not feed on anything that contains the previously mentioned toxic compounds. If farmers are uncertain about certain plants, it is recommended not to avail them until acquiring adequate information about their chemical composition.