APPLY PESTICIDES CORRECTLY
A GUIDE FOR COMMERCIAL APPLICATORS
DAIRY
PEST CONThOL
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF PESTICIDE PROGRAMS
WASHINGTON. D.C. 20460
-------
CONTENTS
Acknowledgments 2
Preface 2
Pests of Agricultural Animals 3
Pest Identification 3
Common Dairy Pests 3
Houseflies 3
Horn Flies 3
Stable Flies 3
Face Flies 4
Horse Flies 4
Blowflies and
Wound Infesting Larvae 5
Mosquitoes 5
Heel Flies and
Cattle Grubs 5
Cattle Lice 6
Biting Lice 6
Blood Sucking Lice .. .*. 7
Scabies and Mites 7
Ticks 7
Pesticide Application Techniques 8
Pesticide Safety 8
Pesticide Toxicity 8
Pesticide Formulations 8
Residue Potential 8
Precautions and Suggestions 8
ACKNOWLEDGMENTS
This guide has been developed by the South Dakota
Cooperative Extension Service under Environmen-
tal Protection Agency contract number IGA-EPA-
78-D-F-0471 issued by the District VIII Office of
Pesticide Programs. The leader of this effort was
Wayne L. Berndt, Extension pesticides specialist,
South Dakota State University. Editors were John
L. Pates and Mary Brashier, Agricultural Informa-
tion Office, South Dakota State University.
Contributors were
David Stout, Extension pesticide education
specialist, SDSU
Hollis Hall, director, South Dakota Cooperative
Extension Service
Lou Johnson, head, District VIII Office, EPA,
Denver
Dallas Miller, EPA. Denver
Leland Sudlow. Extension visual aids specialist,
SDSU
Jan Wentz, graphic artist, SDSU
Dewitt Baulch. EPA, Denver
Appreciation is expressed to Shell Chemical Com-
pany for use of insect illustrations.
PREFACE
Pest control through use of pesticide chemicals is
an acceptable and necessary part of pest manage-
ment systems.
Federal and state regulations set standards that
you must meet before you use certain pesticides or
apply them for hire.
This guide contains largely general information
about dairy pests but does not contain specific
recommendations. This is largely avoided since
registry and recommendations are constantly sub-
ject to change. Your State Pesticide Regulatory
Agency and your Cooperative Extension Service by
way of your county agent can give you this informa-
tion.
-------
PESTS OF
AGRICULTURAL
ANIMALS
Agricultural animals are attacked by mites, ticks,
and insects. These pests affect the animals through:
• loss of blood,
• lowered milk production,
• lowered resistance to diseases,
• spread of diseases and parasitic worms,
• slower weight gains, and
• death of some animals.
It is a known fact that certain pesticides used on lac-
tating dairy animals or on crops destined for feed to
those animals can be secreted in the milk. These il-
legal residues can be detected in normal milk
marketing channels.
However, there are certain pesticides that are not
secreted in the milk. If used in a manner prescribed
on the label, they are safe dairy pest controls.
Because a dairy operator must take special care in
his choice of pesticides, he does not need to accept
"second best" from the standpoint of performance.
The "safe" materials are fully effective and will per-
form satisfactorily. The operator only has to use
those pesticides in a responsible manner.
PEST IDENTIFICATION
Pest identification is an important first step in pest
management. Without proper pest identification, a
chemical may be applied at the wrong time, to a
non-economic species, or even to a beneficial
species.
Most producers know • the usual pests. But
sometimes unfamiliar ones may be encountered.
You can get identification aids and publications
from your Extension county agent.
COMMON DAIRY PESTS
Houseflies
Houseflies have been implicated in the spread of
practically every bacterial disease of man and
animal. Their very habitats are inducement enough
to initiate controls about the farmstead, including
the home.
Less familiar are the egg. larval and pupal stages.
Female houseflies lay their eggs on almost any spoil-
Housefly
ing or decaying organic matter. Wet animal
manure is a favorite place.
The eggs hatch in a few hours into larvae, more
often called maggots. After reaching full growth
they pupate to emerge as adult flies in 5 to 10 days.
Sanitation is the most fundamental approach to fly
control: it may even be a satisfactory control alone.
Certainly sanitation is a valuable supportive
measure to chemical controls.
Horn Flies
The horn fly is a blood sucking fly about half the
size of the housefly. Horn flies stay with the cattle
day and night, leaving only to lay eggs or to migrate
to another animal. Constant irritation set up by
feeding activities of horn flies causes restlessness and
subsequent reduced grazing.
Horn flies lay eggs and breed in fresh cattle drop-
pings. A generation is completed in about 21 days
during the summer months.
Sanitation is unworkable as a cultural control in the
case of the horn fly. Control is possible by direct
pesticide applications to the host animal by use of
dusts, back rubbers, and sprays.
Stable Flies
Stable flies look very much like houseflies. are
found in much the same resting places, but are
quickly identifiable by the forward projecting
mouthparts.
-------
Horn Fly
Although they are blood sucking flies, stable flies do
not remain with the animal for any great length of
time. Adult stable flies spend their time roosting on
shady vertical walls or fences. As animals move into
the vicinity, the flies leave their roosting places for
the animals, usually congregating on the lower
body and the legs. There they work down into the
hairs and feed rather aggressively for a short period
of time. After taking on a good blood meal, the flies
leave the animal and seek a roosting place to rest
and digest their meals.
The feeding activities of the stable fly are painful to
the animal.
The breeding site for stable flies is rotting vegetable
matter—including rotted hay, bedding, or feed.
Stable Fly
Regular disposal of manure assures a good measure
of control against both the stable fly and housefly.
Recommended residual sprays are equally effective
for both stable flies and houseflies.
Face Flies
Face flies are relative newcomers to this continent.
and they are now important pests of livestock in the
Midwest. The face fly is very closely related to the
housefly, although their breeding and feeding
habits are not similar.
Face flies feed on the moist mucous membrane
around an animal's eyes, nose, and mouth. They
may also be found on other parts of the body,
feeding on saliva or wounds from heavy horn or
stable fly breeding.
Face flies feed when the host animals are in
sunlight: when the animals reach shaded areas or go
into sheds the flies leave to roost on nearby vegeta-
tion or fences.
Chemical control is generally impractical. Daily
hand treatment of animals or daily forced use of
dust bags or oilers gives the animals some relief.
Horse Flies
Horse flies are known for their vicious biting at-
tacks. These flies have slashing knife-like
-------
Carcass and offal disposal is another way to cut
down fly breeding in the neighborhood.
Sprays and medicated smears are effective in con-
trolling wound infestations in animals.
Horse Fly
mouthparts rather than piercing, sucking
mouthparts. To feed, the horse fly makes a cut in
the animal's skin and laps up the blood as it oozes
from the wound.
The female fly must feed on animal blood;
however, the males feed on nectar from flowering
plants.
Horse flies breed in standing shallow water contain-
ing a high amount of organic matter. Eggs are laid
by the female fly on plants overhanging water.
When the eggs hatch, the larvae drop into the water
and feed on microscopic animal life in the mud.
Adult flies emerge from the pupal cases, thus com-
pleting the cycle. Populations are more numerous
during early summer.
Control of horse flies is poor at best; however,
sprays and drainage programs wherever possible
will give animals some relief.
Blowflies and
Wound Infesting Larvae
Blowflies are otherwise known as blue bottle or
green bottle flies. They have a preference for
wounds and animal carcasses upon which the larvae
breed. The female fly lays her eggs in infected
wounds; the eggs soon hatch into maggots which
burrow into the wound. Like most of the other flies,
the life cycle is about 21 days.
If the infestation is not treated promptly, damage
may be serious enough to cause death.
Early medication of wounds and sores before fly
season is the most effective treatment. Time wound-
producing operations early and medicate the
wounds thoroughly.
Blowfly
Mosquitoes
Mosquitoes are most abundant in areas where an
abundance of standing water provides suitable sites
for egg laying and larval breeding.
Mosquitoes attack cattle day or night, causing
enough discomfort to stop grazing. Besides the
distress they cause, mosquitoes can transmit such
blood parasite diseases as anaplasmosis,
encephalitis, and malaria.
The most often recommended control is elimination
of breeding sites—the standing water. No one
chemical control method is effective; a broad adult
and larval control program is required for
reasonable effectiveness.
Heel Flies and Cattle Grubs
The larval stages of heel flies are more familiar as
cattle grubs or ox warbles in the backs of cattle.
There are two main species of heel flies (or cattle
grubs) in the United States: while their life cycles
differ, we can consider them together.
The life cycle begins with the mated female fly lay-
ing eggs on the cow's hair over the legs and flanks.
It is this egg-laying activity that causes cattle to
-------
Mosquito
react in a characteristic manner, running wildly
with the tail arched over the back or spending the
day standing in water.
The larvae hatch in a few days, burrow through the
skin, and migrate into the animal's tissues. After a
number of months the larvae of one species (the
northern grub) localize near the spinal cord,
migrating later to subdermal positions in the
animal's back. Here they make holes in the skin
through which they breathe and later emerge. Once
fully developed the larvae emerge, drop to the
ground, and pupate to emerge later as adult flies.
There is only one life cycle per year.
Control of cattle grubs can be achieved by use of
systemics on dry cows and replacement heifers.
Lactating dairy cows cannot be treated.
Cattle Lice
Generally, cattle lice are more abundant during
winter months and scarcer during the summer.
Enough lice remain on animals in the summer to act
as a reserve population for the succeeding winter
months.
Cattle lice spend their life cycle entirely on the host
animals; they spread through the herd by close con-
tact with infested animals.
Heel Fly
(Common Cattle Grub)
When infestations become heavy cattle will be seen
rubbing fences, posts, trees, and other solid objects
in an effort to relieve the intense irritation. If the in-
festation is untreated and the case becomes more
advanced, the cattle become unthrifty, lose weight,
and, in the case of sucking lice, become anemic and
subject to disease.
If the infestation is allowed to advance further, the
animals may die.
Two main types of lice may infest cattle: sucking
lice, commonly referred to as blue lice, and biting
lice, more commonly called red lice.
Biting Lice
Feeding activity by biting lice is confined to skin,
scales, and hair. This feeding activity causes intense
irritation and loss of hair coat, reducing the
animal's ability to withstand extreme winter
temperatures. Resistance to diseases is also lowered.
The biting louse is very small, reddish brown, and,
even under average conditions, seen and identified
with difficulty. Symptoms are usually apparent
before the lice are visible.
The life cycle is fairly short. Eggs are laid by fertile
females, each egg being glued singly to the cow's
hair. Eggs hatch into nymphs and, after a series of
molts, become fully developed adults. The life cycle
takes about 3 weeks.
-------
Biting Louse
Blood Sucking Lice
The primary damage caused by sucking lice is the
loss of blood. Heavy, untreated infestations result in
anemia and, in advanced cases, death of the host.
Sucking lice are large; and infestation is easily
detectable. When sucking lice are fairly numerous,
the host animal takes on a dirty, greasy appearance.
Close inspection discloses the lice next to the skin
and multitudes of eggs glued to the hairs.
The life cycle of sucking lice is very similar to that of
biting lice.
Blood Sucking Louse
Scabies and Mites
Scabies is a specific skin condition caused by a mite.
The mites that cause scabies are microscopic and
cannot be seen by the naked eye. Scabies mites bur-
row into the epidermis, feeding as they go. Infested
animals spend a good deal of time scratching and
rubbing in an attempt to relieve the intense itching.
Further symptoms include scabs, scaliness, and ex-
cessive hair loss.
Scabies is transr litted by contact with an* nals or by
grooming and 'waning tools.
Scabies treatment is regulated by state and ederal
quarantine laws. If scabies is detected in a herd it is
mandatory to report the infestation to the Livestock
Sanitary Board.
Treatment of infested animals by dipping in
specified pesticide materials is the prescribed prac-
tice.
'flGS
Cattle Scabies Mite
Ticks
Ticks are blood sucking pests of livestock but are not
true insects. Ticks are large and hard shelled. They
live free for a large part of the life cycle, going to
the host only long enough to secure a blood meal.
The life cycle begins when a fertile female lays her
eggs on the ground; the eggs hatch into small "seed
ticks" which will climb onto vegetation and feed on
small rodents and then molt and grow to a larger
size nymph. These nymphs feed on larger mammals
such as foxes, coyotes, dogs, and cattle, dropping
off to grow and become sexually mature adults. The
-------
Brown Dog Tick
adults mate and the female lays her eggs on the
ground, completing the life cycle.
This blood feeding habit coupled with a continual
transfer from animal to animal set up ideal condi-
tions for transmission of virus diseases from animal
to animal and from animal to man. A number of
tick borne diseases can be easily transmitted in cat-
tle.
Dips and sprays are somewhat effective for the con-
trol of ticks. Clearing underbrush in a pasture, thus
reducing harborage, will help with tick problems.
Pesticide Application
Techniques
When using contact pesticides for external
parasites, it is imperative that the pesticides reach
the pest. When using power equipment, you may
need to increase the pressure to get sufficient
penetration through the hair coat.
For applying liquid contact pesticides, use:
• power sprayers,
• knapsack sprayers,
• compressed air sprayers,
• rubbing devices (back and face rubbers), or
• pour-on treatments.
Dusts may be applied by:
• power dusters,
• knapsack dusters,
• rubbing devices, or
• individual hand treatments.
Systemic pesticides, which are transported
throughout the animal's system, are applied as:
• pour-ons
• spot treatments,
• sprays,
• feed additives, or
• dips.
Pesticide Safety
Pesticide Toxicity
Pesticides can protect animals from pests, but they
may be toxic to the animals being treated as well as
to the pests. Apply correctly to prevent adverse ef-
fects. Poisoning signs usually include excessive
• salivation,
• eye watering,
• defecation,
• urination, and
• muscle twitching.
Do not treat animals which are under stress. Be
careful not to overdose young or smaller animals.
When planning a pesticide application, choose the
pesticide which has the least risk of adverse effects
and will give good control.
Pesticide Formulations
Consider how the pesticide formulation will affect
the animals. Sprays are generally suited for treating
most animals, except in freezing weather. Some
pour-ons, smears, and dust formulations are recom-
mended in cold weather. Do not let oil sprays
penetrate the hair to the animal's skin in any
weather, unless directed on the label.
Residue Potential
Follow the label recommendations closely for time
intervals between application of pesticides and
slaughter or marketing. Failure to do this can result
in illegal residues in meat, milk, or eggs. The
animals or animal products may be confiscated and
you could be prosecuted.
Precautions and Suggestions
1. Treat only with pesticides specifically labeled for
dairy premises.
2. Read and heed all label instructions.
3. Do not treat any lactating animal without first
reading the label.
4. Cover all feed and feeding equipment and
utensils before spraying.
-------
5. Observe specified withdrawal periods in the case
of pregnant cows about to calve.
6. Use clean pesticide application equipment, and
clean again after use.
------- |