Grazing Weeds in Pasture


Wet summer increases weed pressure in grazing pasture

As the temperatures begin to rise, most pastures will begin to mature, leading to a decline in digestibility, energy, protein and many vitamins and minerals. The low value of this feed creates an alternative and more appealing appetite for freshly growing green feed. This can be in the form of weeds in pasture, irrespective of the presence of anti-nutrient factors.

Some common summer weeds in pasture can be toxic to livestock

Common summer weeds in pastures, Hairy panic, heliotrope and caltrop are prolific in this region, and can regularly contain up to 12-20% protein (NSW DPI) and 7-10MJ ME/kg DM. However, these weeds can be toxic to livestock when consumed. Restricting access to these weeds is often the best management practice. However, in a time of limited feed availability; avoiding infested paddocks can be difficult. If toxicity can be managed, the energy and protein supplied by these common weeds can be partitioned towards growth.


Spraying weeds in pasture can increase weed palatability

A common management strategy such as spraying weeds in pasture can be beneficial, however, spraying can increase the palatability of some weeds and in some cases predispose stock to greater toxin overload.

Grazing management

In regards to on-farm efficiency, avoiding certain paddocks for grazing on the basis of weed risk is not a viable prospect. With the application of simple grazing management practices, the stock may be able to utilise the nutritive value of weeds while avoiding consequences commonly attributed to the ingestion of weed toxins.

Dilute weed toxins with hay or straw

Dr Paul Meggison, Chief Nutritionist, at AusFarm Nutrition Products recommends dilution as the most organic form of dealing with livestock grazing toxic weeds in pasture. “By feeding hay or straw to livestock in high-risk paddocks you can somewhat offset the concentration of toxins and the animal’s reliance on nutrients present in weeds.”

Toxin binder supplements can reduce the effect of toxins

Offering a mineral supplement like StockMins-Detox, containing effective toxin-binding technology, antioxidants and essential trace elements and minerals, can assist in reducing the effect of toxins, repairing damaged tissue and clearing the toxin from the system.


There are many varying signs of toxicity from grazing different weed varieties that pop up in pastures; the most common initial indications include photosensitisation, head and eye swelling, drastic weight loss and jaundice. This chiefly stems from a dysfunctional or damaged liver caused by the ingestion of alkaloids and/or other toxins. Other, longer-term symptoms of toxicity, particularly in sheep, include ill thrift, permanently depressed growth rates, abortion in ewes and, in many cases, mortality.


Unlike other diseases, many of the signs and symptoms of weed toxicosis are quite noticeable, and if diagnosed early, corrective action can be adopted before significant damage is done. Sheep presenting with clinical signs of photosensitisation should be removed from the offending paddock and placed into a well-shaded area with access to clean fresh water and cereal hay. It is important to restrict the affected animal’s access to “green feed” as the damage incurred to the liver reduces its capacity to appropriately process chlorophyll (green pigment) subsequently compounding the severity of photosensitisation.


StockMins-Detox is the first product of its kind, available for cattle and sheep, and can reduce the effects of toxins in three distinct ways:
• Protecting against the absorption of a variety of harmful toxins.
• Stimulating and supporting enhanced liver function.
• Assisting with tissue recovery and repair.
Additionally, StockMins-Detox contains AusFarm Nutrition Products’ proprietary blend of key minerals and trace elements that promote optimal health, improve feed conversion efficiency and elevate immune response. Through the three distinct mechanisms, StockMins-Detox offers farmers an additional management tool to help maximise the use of summer pastures without the threat of toxins impacting animal health, welfare, and productivity.

Early reports suggest that StockMins-Detox is effective against grazing St John’s Wort

Mounting anecdotal evidence suggests that StockMins-Detox has been effective in helping offset toxic insult from St John’s Wort in sheep.


StockMins-Detox Product Summary

Call AusFarm Nutrition Products on 0412048055