Dairy : Detection and Management of Pests Affecting Dairy Cattle

Detection and Management of Pests Affecting Dairy Cattle

The following outline is intended as a quick reference guide for detection and management of cattle pests. Pesticide information is accurate as of February 11, 1991. Always read the label carefully before applying any insecticide. Consult with your local extension agent or specialist
for updated control information.

House Fly:
Pest Status: Sanitation, nuisance, "public relations "
Detection: Place 3"X5" index cards in areas of fly activity in barn
Threshold: 100 spots per card per week (fewer in high-density residential areas)
Management:
Cultural: remove fly breeding areas (esp.calf bedding) weekly
Mechanical: Sticky ribbons, light traps
Biological: Releases of wasps are effective if combined with manure management and
avoidance of certain insecticides. A void use of residual fly sprays, especially permethrin
(Ectiban, Atroban) and Ciodrin until August to conserve beneficial insects even if you are
not making releases. If purchasing wasps, buy locally and insist that you receive Muscidifilrax raptor .
Chemical: Flies are becoming resistant to most of the insecticides that we use to
control them. Resistance problems are aggravated by relying on a single insecticide
year-round, year after year. You can help prevent resistance by alternating
insecticides, using different kinds to handle different problems. Some usage examples:
* Baits such as Improved Golden Malrin and' Apache are highly
effective against small to moderate fly populations.
* Space sprays with pyrethrins or Vapona provide rapid and effective control but have no residual activity. Good for managing sudden outbreaks of flies with minimal damage to
beneficial insect populations.
* Residual premise treatments should be used as a last resort for control problems in late summer: Use Rabon or Ciodrin through late July; switch to permethrin (Ectiban, Atroban) in August if control is unsatisfactory .
Stable Fly:
Pest Status: Blood-feeding causes. direct production losses, animal discomfort.
Detection: Cattle stamp their feet to shake flies off their legs and ankles. Appearance
similar to house fly except for stiletto-type mouthparts.
Threshold: 10 flies per animal (count flies on animal.s' legs.)
Manaegement: Same as for house fly. Whole animal sprays, dust bags, backrubbers also
will relieve immediate problem.

Horn Fly:
Pest Status; Blood feeding causes direct production losses, poor gain in replacements.
Detection: Small flies on pastured animals' sides and backs
Threshold: 50 flies per side.
Management: Ear tags such as Ectrin, Atroban, Guardian (wait until July);Boluses
such as Vigilante (wait until July); Backrubbers and dust bags (ciodrin, Rabon, Ectiban); Whole animal sprays for short-term control (Atroban, CioVap).
Face Fly:
Pest Status: Annoyance causes production losses, poor gain; also transmits pinkeye
bacteria and eyeworms.
Detection: Count flies on pastured animal's faces. Will not enter barns.
Threshold: 10 flies per face.
Management: Difficult to control. Ear tags (see horn fly) provide partial control. Whole
animal sprays and dust bags are reasonably effective.

Cattle Grub (=Heel Fly):
Pest Status: Adult flies terrify animals. Migration of larvae damages tissue. Warbles damage hide. Reduced gain of replacements.
Detection: Look for warbles on backs (February & March) or eggs on legs (July &
August).
Threshold: Not known.
Management: There is NO legal treatment for lactating animals. U se systemics
(Tiguvon, Neguvon) in mid-September through mid-October on pastured heifers.
Lice:
Pest Status: Annoyance leads to hair loss, production losses, poor gain; infested
animals are irritable an more hazardous for human handlers.
Detection: Part hairs on neck and tail base area and examine for lice with the aid of a
flashlight. Pay particular attention to calves. Monitor animals regularly throughout the
year; don't wait until hair loss makes the infestation obvious.
Threshold: 10 lice per square inch of skin. Treat the entire herd if more than 25% of
animals are infested .
Management:
Cultural: Use of calf hutches eliminates 90% of infestations on young animals. Be
careful when buying replacement animal; isolate and treat (if needed) before allowing
them to mingle with herd. Inspect heifers and treat (if needed) before moving them in
with milkers. Calves born in August and September are rarely infested.
Chemical: Use whole animal sprays such as Atroban, Taktic, or pyrethrins in the
warmer months. A void chilling in winter by using dusts (eg. CoRal) or an oil pour-on
(eg. DeLice). Read the label! If a second treatment is recommended 10-14 days after
the first, be sure to do it (the eggs are insensitive to insecticides). Dust bags are effective if positioned so that animals make frequent contact with them.

Sarcoptic Mange Mites:
Pest Status: Sarcoptic mange is reportable disease that has very severe effects on
animals health and performance.
Detection: The appearance of hair loss, scabbiness, or crusty or bloody skin lesions
suggests the presence of sarcoptic mange. The mites are microscopic and live deep under the skin, so proper diagnosis requires the services of a veterinarian or other trained professional.
Threshold: One mite on one animal.
Management: Herd placed under quarantine until every animal has been treated under
the supervision of a state veterinarian. Home remedies with lice and fly sprays are ineffective.

Chorioptic Mange (=Barn Itch) Mites
Pest Status: Itchiness, dermatitis causes production losses, poor gain, hazards to
humans wo!king around animals.
Detection: Symptoms vary but overlap with those for sarcoptic manage. As with Sarcoptic mange, the mites are very small, so proper diagnosis requires the services of a veterinarian or other trained professional.
Threshold: Not known.
Management: Use Taktic or Ciodrin applied
as a whole spray.

A WORD ABOUT IVOMEC. Many farmers ask whether they can use Ivomec on their heifers and dry cows. The answer is "no", the label restriction states that it may be used on "dairy cattle of breeding age".

WRITTEN BY: C. I. Geden, Department of Entomology, Comell University.