Mimeo Report VY70-3
TOXICITY PROBLEMS IN BEEF CATTLE
Paul T. Cardeilhac, D.V.M., Ph.D..
Department of Veterinary Sciehce
University of Florida
Gainesville, Florida 32601 U.S.A.
This paper was presented at the
Training Program for County
Extension Directors and Extension
Agents-Livestock in Beef Cattle
Production and Marketing.
I'ay 27, 1970
A number of toxicity problems are known to occur in beef cattle.
These problems can be roughly divided into 4 classes.
1) Poisoning from the accidental ingestion of toxic amounts
of agricultural chemicals and drugs.
2) Poisoning as a result of contamination of feedstuffs from
improper handling of feed or as the result of the growth
of microorganisms in the feed.
3) Poisoning from inorganic substances.
4) Poisoning from the ingestion of poisonous plants.
Poisoning by Agricultural Chemicals
The possibilities for poisoning in this group are large and grow-
ing each year as the chemical industry and commercial agriculture
combine to develop and release biologically active agents directed
toward specific agricultural problems. These agents are usually
safe when properly applied, but because of their biological activ-
ity, present a hazard to cattle (Table 1). Cattle may acciden-
tally come in contact with agents such as rodenticides, insecti-
cides and herbicides used in the control of pests. This contact
may result in death or poor performance of the animals.
Poisoning as a result of the contamination of feedstuffs.
The contamination of feedstuffs can occur in several ways. Natural
toxic products may be produced under certain circumstances by the
plant itself (Table 2). These toxic products may not ordinarily
be produced or would usually be removed by processing. Occasion-
ally, insects which contain toxic substances have been reported to
occur in high concentrations in hay or feed. Grains which were
intended for planting have found their way into feedstuffs. Seed
grains may have been treated with a fungicide and these fungicides
have.poisoned both animals and humans. A recently recognized and
more serious problem in the contamination of feedstuffs results
from the growth of toxin-producing microorganisms in the feed.
Contamination from microbial toxins usually results from improper
handling of the feed.
Poisoning from Inorganic Substances
The poisoning of animals by inorganic substances is one of the
oldest areas of toxicology. Lead and arsenic are still common
causes of poisoning and present a hazard to beef cattle in the
form of paints, pesticides, discarded batteries and other materials.
Cattle are particularly susceptible to acute lead poisoning.
Fluorine and selenium can be serious localized problems when
industrial contamination or other special circumstances such as a
seleniferous range are encountered. Nitrates are normal constit-
uents of many plants and nitrate concentrations often increase
after the plants have been sprayed with a weed killer such as
2, 4-D or after heavy fertilization.
Poisonous Plants (Table 4)
The effects of poisonous plants on livestock continue to produce
losses each year. Cases of plant poisoning in cattle usually
follow droughts and overgrazing. Cattle do not usually prefer
the poisonous plant to forage plants and avoid the poisonous
plant even though they are mixed with forage plants.
Specific conditions may result in animals ingesting poisonous
plants as follows:
1. Hungry animals released into a pasture containing
2. Poisonous plants and poisonous seed mixed with good
hay and grain during harvest.
3. Overgrazed pastures.
4. 'Animals watered after a long period of water restriction.
It is apparent that toxicity problems in beef cattle will probably
increase. Older problems remain and new problems arise as new
agents and methods are developed to combat agricultural problems.
Cardeilhac, P. T. Mycotoxicoses of Importance to the Bovine
Practioner. The Bovine Practioner No. 4, 20-25 (1969).
Radeleff, R. D. Veterinary Toxicology, Lea & Febiger, Philadelphia
Garner, R. J. Veterinary Toxicology, 2nd Fd., Williams and
Wilkins, Baltimore, (1963).
PESTICIDES WHICH PAY CAUSE TOXICITY PPOPLFMS IN PFEF CATTLE
AGENT EXAMPLES COMMON SRYPTOM FIRST AID
Cyanoses, Edema of Lungs
Salivation, labored breathing,
Irritation of unpigmented areas
of the skin and eye, Depression
Depression, weakness, diarrhea
I I" 7
rapid breathing, depression
death, depression, inanpetance
AGENTS WHICH MAY CAUSE POISONING DY CONTAMINATING FEEDSTUFFS
AGENT EXAMPLES COMMON SYMPTOM FIRST AID
Ergot or tall fescue
Paw lineseed meal
Rapid breathing, shivering,
Eight loss, death
Rapid breathing, depression
Decreased growth rate (young)
V 1 G. 9;
Remove (red clover hay)
POISONING OF BEEF CATTLE BY INOPGAPIC COMPOUM.DS
2'.GEN T ESTIMATED OCCURRENCE COTTON SYMPTOMS FIRST AID
Animals very weaK and
Labored breat'ling, convulsions
Depressed, gr'inting, constipation
Changes in teeth and bones
Violent diarr'iea, shock,
POISONOUS PLANTS WFICH MAY AFFECT BFEF CATTLE
OCCUPRENCE IN FLOPIDA COMMON SYMPTOMS
Northern Diarrhea, dehydration, depression
Usually planted Papid death, bright red blood
South to Lake Figh temperature, stand with head
Okeechobee down and drool. Ploody fluid
Common in Northern Dry mouth, rapid pulse and
Common Sluggishness, extreme weakness
South of Orlando bloody feces, skin irritation
Old gardens & homesites
All of Florida Naus6a, vomiting, purging
1 xative feeds