By: Eddie Ayers, County Extension Agent

The drought last fall has led to the lack of quality forages for cattle.in our area and because of this, cattle are feeding on plants that they normally do not eat. One of those plant species is oaks and their acorns and they can be toxic. While most cattle might find acorns unpalatable, hungry cattle might eat enough acorns to cause potential death. With grazing so limited it is more likely that cattle might get into oaks that border pastures and graze on acorns looking for additional nutrition so producers need to understand what acorn toxicosis looks like in cattle and how to prevent it.

Oaks, like many nut-bearing trees, produce tannins. These tannins are complex chemical compounds that are responsible for the flavors in things like nuts, coffee, tobacco, and wine. When cattle consume acorns that contain tannins, the chemical compounds are metabolized into tannic acids that cause ulcerations in the mouth, esophagus, gastrointestinal tract, and kidneys. Because of the effect on the animals’ kidneys, renal failure is a common problem preceding death resulting from acorn toxicosis.

In cow herds, calves would likely be the first ones to exhibit acorn toxicosis. Tannins concentrate in milk, so nursing calves could be exposed to tannic acids without having eaten the acorns themselves. Initial symptoms will likely include constipation and decreased feed intake. Continued exposure will result in increased ulceration of the gastrointestinal tract, which will become apparent through the symptoms of black, watery diarrhea (that may or may not contain blood) and be characterized by an extremely foul odor. Calves will likely be lethargic with edema (swelling) in the abdomen and extremities. In the advanced stages, blood may drain from the nose, and calves may have difficulty urinating and defecating, marked by straining. In adult animals symptoms will be similar with the addition of agalactia (reduced lactation) in lactating cows, and potential birth defects in calves born to poisoned, pregnant cows. Producers should understand that the symptoms of acorn toxicosis are very similar to Bovine Viral Diarrhea (BVD) Type 2. The major differentiating factor is the presence or absence of a fever. Type 2 BVD is characterized by highly elevated body temperature, while acorn toxicosis will likely be present with little or no fever at all.

There is no known medical treatment to combat the acorn toxicosis itself. However, moving animals off of acorns and providing proper care can reduce the likelihood of death in some adults and calves. Contacting your veterinarian at the first sign of symptoms is recommended. Administering fluids and electrolytes to preserve kidney function is important. If urination stops, kidney failure is likely and death could occur soon after. If constipation is observed, administering mineral oil can help as a laxative. A veterinarian should be consulted if considering administering a broad-spectrum antibiotic to combat infection from ulcers formed by the tannins.

As with dealing with any toxic plants in pastures and hayfields, prevention is the best method of control. Moving cattle off of pastures where oaks or acorns are present is important. You could simply move them to another pasture or sacrifice paddock to feed hay or temporarily fence cattle away from oak trees. If removal from the area is not possible, feeding a combination of hydrated lime, molasses, soybean meal, and corn could help prevent the effects of acorn toxicosis, though consultation with a veterinarian and careful feeding is recommended. Feeding high quality forage, feed, baleage, or winter grazing would be the best way to prevent cattle from scavenging on acorns or being overly hungry when near oaks.

For more information on this subject and about poisonous plants, contact me in the Gilmer County UGA Extension office. UGA Extension Cattle Team Member Adam Speir provided information for this article.

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