Immature acorns can lead to serious livestock problems 

By LYNN MONTGOMERY | East Texas Edition

Horses can be negatively affected by acorns, but cattle often suffer the worst problems after eating them. Sheep and goats are rarely affected from the nuts. -- Staff photo by Montgomery

Dec. 8, 2005 -  Oak tree leaves are dropping their fall-colored leaves, as well as something else which can be deadly to some animals – acorns.

�Cattle are the most susceptible to developing acorn poisoning from immature acorns, but horses may also be affected if enough acorns are eaten.

�Acorn poisoning is caused when the animal over-eats the oak�s nuts, which contain a chemical called tannins within its shell.

��You don�t need to have that much concern with white oak or live oak trees,� Dr. John Reagor, Texas Veterinary Medical Diagnostic Lab�s head of diagnostic toxicology, said. Acorns from these trees have less tannins than other oak trees.�

�How much an animal can eat before getting sick depends upon the quality of that animal�s diet, according to Van Zandt Extension Agent Brian Cummins. �The quantity tolerated by an animal is influenced by the protein content of its diet, with the higher protein intake allowing the consumption of more acorns without poisoning symptoms.�

�Cummins added cattle usually become sick eight to 14 days after they begin to eat the acorns. These animals will appear �dull, have a poor appetite, become constipated, suffer weight loss and look gaunt. They may also pass blood in the manure and/or bleed from the nostrils. Diarrhea may follow after the constipation. Affected animals may drink large amounts of water.�

�Symptoms in horses are different. Horses will have colic-like symptoms, be depressed, and �over a period time, more liver and kidney damage, than a cow,� Reagor said.�

�Dr. Pete Gibbs, Texas A&M equine specialist, noted there is a �bigger chance of (the immature nuts) causing problems for a horse that has not been around the acorns as they start to come off (the tree), compared to a horse that has been turned out in the location for a long time, has plenty of grazing and/or hay, and is less likely to eat a large amount in a short time period.�

�Other animals are not as susceptible to the acorn�s potential poison effects. Reagor added, �We very seldom see problems with sheep or goats.�

�What does a cattle producer do when there are oak trees are in their pastures?

�Cummins suggests providing supplemental feed which contains hydrated lime (calcium hydroxide) and protein, which are antidotes for tannins. The feed mixture, which should be fed at the rate of four pounds per head per day, includes 1,040 pounds of cottonseed meal, 640 pounds of dehydrated alfalfa meal, 160 pounds of vegetable oil and 200 pounds of hydrated lime.�

�The hydrated lime makes the rumen less acid and lets the animal pass the acorns through without becoming toxic,� Cummins concluded.

Reagor stated he didn’t know of a company which still makes the feed because the hydrated lime is very corrosive.

He suggested producers can rather make sure there is plenty of good quality forage or feed for the animals to eat.

�With cattle, make sure the feed supplement is a natural protein versus an urea feed. Over the years, we have seen lots of wrecks with the urea,� Reagor said.

The main focus for animals in pastures with oak trees is to make sure there is something beside the acorns for them to eat.