Title: ACBS 405/505: Principles of Livestock Health Management
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ACBS 405/505:
# Principles of Livestock
# Health Management
> Dr. Margie Snchez -Vega
# IV. Goats/Sheep diseases and disorders
We will discuss the following
diseases and disorders:
Bluetongue (sore muzzle)
Caseous lymphadenitis
Enterotoxemia
Foot abscess (bumblefoot)
Foot rot
Lamb dysentery
Mastitis
Scrapie
Tetanus
Vibriosis (campylobacteriosis)
Nutritional problems
Milk fever
Urinary calculi (water belly,
urolitiasis )
External parasites
Internal parasites Before we start with the diseases
Goats graze on poor land with browse plants and have good ability
to control weeks and undesirable plants
In some islands of the Caribbean, like Grenada, Sheep and goats are used
in cemeteries maintenance to keep grass low.
Sheep are raised in every state in the U.S.
Range production is concentrated mostly in western states while native, or
farm flock, production is found in the rest of the country
Small flocks of fewer than 100 head account for more than 90 percent of
all sheep operations but only about 35 % of the inventory
Range production accounts for more than 50 % of the total sheep
> Large flocks of 1,000 to 1,500 ewes are common in these areas
> The production of feeder lambs and wool is located mostly in the southern part of
> the area
Small sheep operations tend to be secondary enterprises Before we start with the diseases (cont.) Before we start with the diseases (cont.)
Many of the western state producers are using mixed grazing, raising cattle and sheep
on the same land
Advantages of mixed grazing
Provides more opportunity to increase livestock production than raising cattle or sheep alone
Wool and lambs provide extra income
Initial costs are low
Enterprise doesnt require expensive housing or equipment
Sheep make use of pasture crops that might otherwise be wasted
Sheep can be fed on roughages and small amounts of grain
Market lamb returns compete well with other meat animal enterprises
Sheep can improve the pasture mix
Lamb, wool, and beef prices fluctuate independently
Disadvantages of sheep enterprises
Sheep are susceptible to internal and external parasites
Predatory animals such as coyotes and dogs prey on sheep
Increased labor and management requirements
Wool prices are quite variable Before we start with the diseases (cont.)
Selecting native or western ewes
Native ewes
Those produced in other parts of the U.S. beyond the western states
Have medium, long, or crossbred wool breeding
Produce a more muscular, leaner carcass
Have a larger lamb crop
Costs are generally less, and these ewes are better adapted to local conditions
Western ewes
Those produced in the western range area of the U.S.
Have a high percentage of fine wool breeding
Less likely to have parasites
Often more uniform in size and are generally hardier and have longer productive lives
Indications of poor health
Dark, blue skins
Paleness in the lining of the nose and eyelids
Lameness
Lack of vigor Before we start with the diseases (cont.)
Sheep and goats do not respond well to treatments; thus, prevention must be a
priority
When they become ill, they frequently do no recover
Sick goats and sheep are hard to identify and often are in late stages of disease before
symptoms are evident
Several diseases in goats and sheep are common also to cattle although the
symptoms show some differences
Actinobacillosis (wooden tongue)
Anthrax
Blackleg
Bloat
Brucellosis
Johnes disease
Leptospirosis
Listeriosis
Malignant edema
Pinkeye
Shipping fever Bluetongue (sore muzzle)
Caused by a virus (a self -reproducing
agent that is considerably small than a
bacterium and can multiply only
within the living cells of a suitable
host)
Occurs mainly in the western U.S.
Spread from sheep to sheep by a small
gnat, a tiny biting midge
Weakens resistance to other diseases
Death (5 %) is usually due to secondary
infections (e.g., pneumonia)
Symptoms include:
Lose appetite
Become sluggish
High fever
Ears, head, muzzle, and lips become
swollen
Tissues inside the mouth become red and
blue
Tongue develops ulcers
Difficulty eating
Lameness
Swelling around the hoof
Bad odor
Discharge from the nose and eyes
No treatment for the disease; can treat
the secondary infections
Vaccination is available
All ewes and rams at shearing time
Replacement lambs at 3.5 months of age Bluetongue (sore muzzle) Caseous lymphadenitis
Contagious disease caused by bacteria
In both goats and sheep
Abrasions or injury to skin, including those incurred during shearing and
castration, can allow entry of the bacteria into the body
Symptoms include:
Abscesses in or near the lymph nodes
May burst open, exposing other animals
Once burst occurs, the bacteria can survive in the soil, on bedding, and on structures for several
months
Best to cull from the herd any animal with an abscess, prior to the abscess bursting
Supplemental information:
If the abscess is sliced in half, the characteristic onion ring profile is evident
Caused by Corynebacterium pseudotuberculosis
Once the abscess is encased in a cyst that hardens, antibiotic likely ineffective
Zoonotic
Thus, if abscess is opened and squeezed, be sure to wear gloves and prevent abscess material from
contaminating any surface (squeeze into a bag that can be sealed shut and properly disposed of) Caseous lymphadenitis Enterotoxemia (overeating disease)
Caused by a bacterium
Toxemia is a condition resulting from the spread of bacterial toxins through the bloodstream
Affects both goats and sheep, with lambs and kids being more severely affected
Symptoms
Dead animal
Head drawn up in an arched and extended position due to convulsions
If the animal is having convulsions (involuntary muscular contractions), death will follow shortly
No treatment once symptoms appear
Controlled through
Good management
Proper feeding
Steady intake of feed or milk
Gradually adjust rations of lambs/kids when increasing the concentrate level
Clean drinking water Enterotoxemia (overeating disease) (cont.)
Vaccination
Ewes/does at 4 weeks and 2 weeks prior to lambing/kidding to prevent the
disease in nursing young
In sheep
After ewes have been vaccinated, annually vaccinate once about 2 to 3 weeks before lambing
Lambs will obtain immunity through colostrum milk
Vaccinate late -weaned lambs twice before weaning, once late in the nursing period and again 2
to 3 weeks later
When practicing early weaning (at 40 days), vaccinate lambs about 10 days before weaning and
again about 10 days after weaning
In goats
Kids should be vaccinated starting at 8 weeks, if still receiving goat milk, and every 21 days
after that for a total of 3 vaccinations
Kids being fed cow milk should be given first of 3 vaccinations at 5 to 6 weeks of age with the
following vaccinations 21 and 42 days after the first vaccination
Dairy goats should be vaccinated twice per year after the initial vaccination
Chilling and stress increase incidence, especially in ewes/does that are
milking heavily and nursing singles
Diagnosed in the laboratory by examination tissues of animals that died suddenly Enterotoxemia (overeating disease) Foot abscess (bumblefoot)
Affects the soft tissue of the foot
Infectious but, unlike foot rot, it is not contagious
It may occur in connection with foot rot when animals
> Are in wet or muddy conditions
> Have had their feet severely trimmed in wet weather
> Are put on stubble pasture
Bacteria enter the foot through injuries, causing pus pockets or abscesses
Symptoms include:
Visible swelling but only if it occurs in the heel
> If in toe or sole of the foot, visible swelling is unlikely
Lameness
Treatment is by draining the abscesses, applying a medicated dressing, and
using systemic antibiotics
Isolate infected animals on soft, clean footing or slotted floors until healing is
complete
Prevent by correcting conditions that cause foot injury Foot abscess (bumblefoot) Foot rot
Caused by the presence of two different bacteria
Both bacteria must be present for the disease to develop
Affects both goats and sheep
It is not the same disease that affects cattle, and it is caused by different bacteria
Extremely contagious
Majority of herd will be affected if outbreak occurs
More likely to occur when animals are exposed to
Irrigated pastures
Wet lowland pastures
Areas with high rainfall
In concentrated enclosures
Less likely to occur when animals are exposed to
Sandy, well -drained soils
Areas with low rainfall
Death loss is low Foot rot (cont.)
Symptoms include:
Lameness
Loosening of the hoof wall
Foul -smelling discharge
It does not form abscesses on the foot
Affected animals move around on their knees
Controlling involves
Regular inspection
Proper trimming of feet
Keeping animals out of wet areas
Keeping bedding dry
Regular use of a footbath
Use a footbath solution
Copper sulfate or zinc sulfate
> Copper poisoning could occur if ingested
> Such solutions corrode metal
> Zinc sulfate solutions are nonirritating and less
> toxic than copper solutions
Keeping areas around feed troughs dry
Treating wet areas with disinfectants or drying
agents
When an outbreak occurs
Separate infected animals from the rest of the
flock/herd
Put affected animals in a clean, dry area
Trim the feet, if necessary
Treat affected feet in a footbath solution
Severe cases involve injection with an antibiotic
Treat every 3 days for at least 4 treatments
Be sure animals are completely free of foot rot
before returning to the unaffected flock/herd
Vaccination is available Foot rot Lamb dysentery
Affects sheep
Mainly lambs 1 to 5 days of age with high death losses
Caused by a bacteria
Symptoms include
Loss of appetite
Depression
Diarrhea
Sudden death
Prevention
Follow strict sanitation practices
Have birthing occur in clean, dry housing and on clean pasture
Vaccination
Ewes should be vaccinated a few weeks prior to lambing
Antibodies are passed to the lamb through colostrum milk Mastitis
Affects goats and sheep, well as cows, mares, and sows
Caused by
Bacteria
Injury to udder
Symptoms include
Swollen udder that becomes hard, hot, and sore
Straddling walk
Milk is thick, yellow, and clotted
Baby animal cannot nurse Mastitis (cont.)
Special considerations for goats and
sheep
Milk production in the ewe reaches a
peak after 4 weeks of lactation and
gradually declines through the 10th to
12th week of lactation
Lambs typically are weaned between 8 to
12 weeks
Lambs can develop enterotoxemia
(overeating disease) if weaned improperly
Thus, lambs should be vaccinated
prior to weaning with Clostridium
perfringens, bacterin, Types C and D
Ewes exhibiting mastitis should have their
lambs weaned as early as feasible
Gangrenous type, referred to as blue bag
is accompanied by fever and, if untreated,
sloughing off of the affected portion
Lambs can pass mastitis to other ewes;
therefore, affected ewes should be
separated from other healthy ewes
Treatment
Antibiotics
Prevention (see also Dairy Cattle for
additional guidance that may pertain
to goats and sheep)
Remove objects in the barn or pasture
that could cause bruises (e.g., high door
sills)
Sanitation
Tag wool from the udder area
Use proper milking procedures Mastitis Scrapie
A disease that affects the central nervous system of goats and sheep
The exact nature of the causative agent is unknown
> There appears to be spreading from ewe to lamb by way of the placenta and placental
> fluids
A test may be used to determine an animals genetic resistance to scrapie
One of a class of diseases called transmissible spongiform encephalopathy
(TSE)
No cure or vaccine
Always fatal
Estimated to cost the U.S. sheep industry more than $20 million each year
Has a long incubation period of 2 to 5 years
> Generally, affects older animals
# Scrapie (cont.)
Symptoms include:
Change in behavior
Scratching or rubbing against fixed objects
Loss of coordination
Walking abnormally, typically high stepping with the forelegs, hopping like a rabbit,
swaying the back end
Weight loss
Wool loss
Lip smacking
Biting at the feet and legs
Under stress, the animal will tremble or go into a convulsive -like state
Confirmation of the disease is by microscopic examination
On the dead animals brain
> Presence of an abnormal prion protein in the brain confirms
On the live animals lymphoid tissue biopsy taken from the inside of the third eyelid Scrapie (cont.)
There appears to be some genetic susceptibility associated with acquiring the
disease and the length of incubation period the Suffolk breed is more
commonly affected although all breeds can become infected
In the U.S., the Animal and Plant Health Inspection Service (APHIS), has
programs in place to control scrapie
A voluntary program since 1992 to bring scrapie under control
Participants certify the origin of their flocks from scrapie -free flocks
Involves a cooperative effort between producers, veterinarians, state health officials, and APHIS
Interstate movement of sheep from scrapie -infected flocks is restricted
The National Scrapie Eradication Program (NSEP) since 2001
Goal is to identify and eliminate the last remaining scrapie cases in the U.S. by 2017
Surveillance will be maintained at sufficient levels for 7 years so that by 2024, the U.S. can meet the
World Organization for Animal Healths requirement for scrapie freedom
Since 2003, the program has reduced the prevalence of scrapie by more than 96 %
Certain classes of goats and sheep must be identified with USDA -approved tags and tattoos Scrapie Tetanus
Affects goats and sheep
Caused by bacteria that produce the tetanus toxin
These bacteria live in the soil
Enter the animals body through abrasions and wounds
Symptoms include
Stiffness
Walking with a straddling gait
Inability to eat
Rigid jaw and tail
Muscle spasms
Respiratory failure
Death
No treatment after symptoms appear
Prevented by
Sterilization of docking, castrating, and shearing instruments
Use of disinfectants on open wounds
Vaccinations for the prevention of enterotoxemia will sometimes
contain a vaccine for tetanus
Recommended for farms where tetanus is known to exist Vibriosis (campylobacteriosis)
Affects goats and sheep
Caused by bacteria
The bacteria is different than the bacteria causing
the cattle disease
Symptoms include
Abortion
One or two ewes out of the flock will abort, followed
by a rapid increase in the rate of abortion within the
herd
Ewes will breed normally again
Management practices to control
Isolate ewes that abort and properly dispose of the
aborted fetus
Move unaffected ewes to a clean area
Vaccination is available
Annually Nutritional Problems: Milk Fever
Caused by lack of calcium in the blood
Affects goats and sheep
Lambing ewes affected
In goats, it occurs shortly after kidding, or it may occur a month or so later in the
lactation period
Symptoms include:
Loss of appetite
Restlessness
Muscle tremors
Difficulty standing
If untreated, can lead to coma and death
Treatment by:
Veterinary care
Prevention by:
Good ration during gestation
Mineral supplement during gestation Nutritional Problems: urinary calculi
# (water belly, urolithiasis)
Caused by formation of small stones (calculi) in the urinary tract
Calculi block the urethra, causing retention of urine
If not treated quickly, the bladder may rupture, causing death
If the bladder does not rupture, the animal may die of uremic poisoning
Affects male goats and sheep on high -concentrate rations
Wethers castrated at a young age have a much smaller urethra and penis and are
more likely to suffer from blockage than intact males
Caused by a narrow ratio of calcium to phosphorus in the diet
The ratio should be 2 parts calcium to 1 part phosphorus
This ratio may drop to 1:1 in a high -concentrate diet
Cold weather
Reduced salt intake
Reduced water intake Nutritional Problems: urinary calculi
# (water belly, urolithiasis)
Symptoms include:
Standing with arched backs
Depression
Low feed intake
Straining to urinate
Calling out kicking at the belly
Abdomen may be swollen, especially if the bladder is ruptured
Penis may be swollen if the rupture has occurred in the urethra
Treatment
If diagnosed early, surgery
Prevention by
Maintaining a proper diet (possibly rely upon chemical analysis of the diet)
Calcium carbonate (limestone) may be added to the ration to increase calcium level
Adding ammonium chloride or ammonium sulfate to the diet may help prevent formation of calculi
Provide plenty of clean, fresh water at all times
In cold weather, maintain temperature at 45 to 50 degrees Fahrenheit to increase consumption
If an outbreak occurs, add up to 4 % salt in the ration to increase urine output and dilute the mineral content of the
urine (but be sure to also make water readily available) External parasites
Several attack both goats and sheep
Cause losses
In production of wool, mohair, meat, and milk
May cause death
Prevention by
Combination of sanitation and correct use of insecticides help control the
most common parasites
Producers being aware of university entomologists, county extension
personnel, or local veterinarian for current information on permissible
control measures External parasites
Blowflies
Lice
Mange and scab mites
Sheep botfly (larvae found
in nasal cavities)
Sheep ked (not a true tick -
it is a bloodsucking
wingless fly)
Ticks Internal parasites
Affect goats and sheep
Cause serious health problems for sheep and
goats
Cause economic loss due to low weight gain,
low milk production, poor wool growth,
wasted feed, lower breeding efficiency, and
death
Symptoms include:
Rough hair coat
Weight loss
Slow gains
Loss of appetite
Diarrhea
Anemia
Swelling beneath lower jaw
Constant cough
Young animals are affected more severely than
older animals
Treatment
Drenching
Oral administration of a liquid medication
Given through the mouth
A syringe or an automatic drenching gun is used
The animals head must be kept in a level
position during drenching
Hold the fingers under the muzzle and the thumb
over the nose
Lift the upper lip with the thumb and carefully insert
the nozzle along the side of the mouth
Administer the dosage and release the animal so that
it can swallow
Prevention
Good management is key to prevention
Two significant contributing factors are overgrazing
and failure to rotate pastures
Eggs of parasites are present in the feces of
infected animals and are deposited in pasture
grasses
Rotating pastures allows time for parasites to die
prior to consumption by grazing animals
Anthelmintics are available for deworming Internal parasites
Coccidia
Liver fluke
Lungworms
Stomach and intestinal worms Questions?
# ?