Download Diseases of the Beef Cow Herd

Diseases of the Beef Cow Herd
By
David R. Hawkins
Michigan State University
Diseases That Impact
Reproduction
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Brucellosis
Leptospirosis
Campylobacteriosis
Trichomoniasis
Respiratory Viruses
– IBR & BVD
Brucellosis
• Bacteria – Brucella abortus
• Localized infection in uterus, udder, testes &
joints – abortion in last trimester of pregnancy
• Diagnose with blood or fetal tissue sample
• Transmissible to humans – undulant fever
• Federally monitored
• Prevent with calfhood vaccination – 4 to 8 mo.
(recommended but not required). Must be done
by DVM – records at MDA
Leptospirosis
• Bacteria – 5 strains
• Fever, off feed, abortion at any time,
anemia, clotted milk & bloody urine
• Diagnose with blood or fetal tissue sample
• Annual vaccination is recommended in
Michigan
• Deer and wildlife can carry the bacteria
Campylobacteriosis
• Bacteria – Vibrio fetus
• Irregular heat cycle (fetus dies after
fertilization and is reabsorbed) (4 to 7 mo.)
• True venereal disease that is spread via
natural service.
• Diagnose with vaginal or preputial mucous
• Vaccinate prior to breeding season
Trichomoniasis
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Protozoa – Trichomonas fetus
True venereal disease
Diagnose with vaginal or preputial mucous
Use A.I., virgin bulls and vaccinate prior to
breeding season.
Respiratory Disease Complex
• Same as earlier discussion with feedlot
cattle.
• IBR, BVD, PI3
• BRSV
• Pneumonia
• IBR and BVD can cause abortion
Calf Scours
• Chronic &/or acute diarrhea of calves – usually
occurs in the first two weeks after birth.
• Causative agents
– E. coli
– Rota/corona viruses
• Sanitation & Colostrum are very important.
• Vaccinate cows prior to calving &/or calves at
birth.
Calf Scours (continued)
• Treatment
– Prevent dehydration with electrolytes
• 8% fluid loss = depression, 12% = death
• 1 quart orally every 4 to 6 hours
– Antibiotics and sulfa boluses.
– Keep calf warm and stress free
– Isolate infected calves to prevent infection of
other calves.
Tuberculosis
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Mycobacterium bovis
Somewhat transmissible to humans
Federally monitored
Michigan was declared free of TB in 1979.
TB found in deer in 1994 and in other wildlife
since then.
• Pneumonia and abscessed lymph nodes.
• Diagnose with caudal fold test.
Tuberculosis (continued)
• Several positive cases have been diagnosed
in northeastern part of lower peninsula.
• Michigan lost it’s “TB free” status, but now
is hoping to achieve “split state” status.
• All bovine in state are being tested. Whole
herd annual test is recommended.
• May take 20 years or longer to eradicate.
Johnes
• Mycobacterium paratuberculosis
• Chronic diarrhea and weight loss
• Incubation period can be several years
before symptoms appear.
• Diagnose with blood & fecal tests
• Cull infected animals and prevent fecal
contamination.
• Some herds are doing annual tests.
Anaplasmosis
• Blood disease spread by ticks, flies and
mosquitos in southern U.S.
• High fever, anemia and death
• Vaccinate &/or treat with antibiotics
• Some states (WI) and Canada require a
negative test before entry
Bluetongue
• Viral disease in western U.S. spread by ticks
& flies
• Ulcers in mouth, fever & lameness
• Vaccinate or treat with antibiotics and sulfa.
Pinkeye
• Inflammation of mucous membranes near the eye
followed by opaque cornea. Acute cases result in
permanent loss of sight.
• Face flies are the primary carrier.
• Vaccinate or treat with cortisone and antibiotics.
Eye patch will protect eye during recovery period
• Breeds lacking pigmentation around eyes are more
susceptible.
Fly Control
• Spraying, dusting, dipping, ear tags & oral
larvacides
• Sanitation – remove breeding sites of flies
• Ear tags impregnated with insecticides have
been very effective
• Change brands each year to avoid resistant
strains.
Lice & Grubs
• Usually apply a “pour-on” organophosphate
compound in the fall.
• Some products are effective for both
internal and external parasites.
– Ivermectin, Dectomax, Eprinex, etc.
• Others are effective only against lice –
Lysoff
• Observe cut off dates for your area
Internal Parasites
• Roundworms, tapeworms and flukes
• Anemia, reduced performance and rough
haircoats are symptoms
• Several anthelmintics (de-worming agents)
are available as bolus, paste, injectable, etc.
• Usually de-worm the breeding herd twice
per year to break the life cycle of the
parasites
Nutritional Diseases
• Michigan is deficient in iodine, cobalt, selenium
and marginal in copper. Most of these can be
supplemented in trace mineral salt.
• Grass tetany is due to a magnesium deficiency in
lush growing forage. Include MgO in mineral
mix, if it is a problem.
• Legume bloat – Poloxalene may help.
• Toxins – some pasture plants can be toxic.