How wild onion poisons your sheep and goats
Spring is that time of the year when farmers are crossing fingers in the hope for the (coming) rainy season.
However, this is also the time that those sneaky poisonous plants are abundant and kill our livestock in numbers. These days, farmers are complaining about their small stock dying from poisoning after eating wild onions. These onions are scientifically called Dipcadi glaucum which is the malkopui (mal- crazy, kop-head, ui-onion) in Afrikaans.
Other local names for this onion are dronkui, slangkop ui, groenlelie, gifui, gifdronkui and wildeui or simply onjanga in some African dialects.
Just like most poisonous plants, the malkopui poisoning is common when grazing is scarce. The plant grows quickly after the first rains especially in September and October when there is very little else to eat. For some reason, poisonous plants are always the ones that grows greener first after the winter season and animals tend to succumb to the green leaves. In Namibia, the plant mostly grows in sandy areas like in Omaheke and Otjozondjupa regions.
Animals that are poisoned by the malkopui become restless depressed and tend to lag behind or far from the rest of the flock. In fact, the poisoned animal isolates itself and will stand alone quietly in a corner in the kraal or field. When touched or frightened, they then suddenly run away wildly. Typical of the name “crazy head” onion, the affected sheep/goats usually behave crazy and often run into obstacles and pushing them as if they can run passes through the obstacles. Even a fence seems to be nothing when a frightened animal tries to force its way through it. In addition to disorientation and dyspnoea, your animal will develop severe diarrhoea and fever, and pregnant ewes may abort.
Another characteristic sign that animals are poisoned by the wild onion is that they will just stand with their heads down in a water trough without drinking. Eventually, the poisoned sheep are unable to stand up after lying down, goes into a coma and die. Cattle are rarely affected but if they do eat the plant, they get disorientation and eventually become lame in their hind limbs, are unable to stand up, commencing with knuckling over of the fetlocks, causing them to stumble.
If you open the carcass, you won’t find much of a typical sign, except the leaves or seeds of the plant in the rumen (big stomach). Thus, the diagnosis is mostly based on the presence of the wild onion that was obviously eaten in the field around where the animals graze and the typical crazy clinical symptom that the animal shows.
Sometimes, the crazy behaviour may be confused with rabies. Pregnancy toxaemia (“domsiekte”, that we have discussed in a previous article), is also another disease that can be confused with malkopui poisoning, but the disease affects heavily pregnant ewes especially with twins, and the liver is fatty and yellowish as compared to the wild onion poisoning.
Like most plant poisoning, there is basically no effective treatment. However, if malkopui poisoning is suspected, you should isolate the affected animals especially away from the field where the plant grows.
Most farmers who deal with toxic plants in animals’ advice is to withhold water from the animals for a day or two, so that the poison is not distributed fast in the body. But is this practical especially when you are dealing with many sheep/goats that need the grazing on a daily basis? Try giving the poisoned animal activated charcoal, a cup in half litre force fed to the animal.
This is supposed to keep the poison from not going fast in the body. Other anti-poison remedies like kaolin and Hypo are also used by farmers after any suspected plant poisoning. Some even mix these remedies in water before the animals go out to graze every day, but this doesn’t help much and besides, it is not practical to do this on a daily basis.
Other “try and error” type of treatments that villagers claim to help is to give the home-made beer (tombo) to a poisoned animal to help to cure it.
Since there is no effective treatment, the best way is to prevent animal grazing in a camp where these poisonous plants grow. (But tell that to a villager without any means of separating his/her animal in camps, it’s impossible). Destroying the toxic plant might help but some grow faster the next season because during the process of destroying it, seeds are distributed at a larger scale.
Poisonous plants are a “curse” in Namibia especially during this time of the year and there’s a variety of them and they affect livestock differently. Thus, be on the lookout to know and identify these plants in your grazing fields so that you can equip yourself in the prevention of toxicity. Don’t look at the animals only, look on the ground too.