Mastitis in Goats
Mastitis may be defined as inflammation of the mammary gland caused by specific disease producing microorganisms. Mastitis in dairy goats, like mastitis in dairy cows, is a disease of considerable economic importance. As in dairy cows, infection is usually spread from infected to non-infected susceptible animals during the milking process.Some aspects of dairy goat mastitis closely resemble mastitis in dairy cows; others resemble the disease in sheep. Subclinical mastitis may be defined as mammary gland infection as revealed by laboratory examination of milk samples. Clinical mastitis is characterized by signs of inflammation: swelling, pain, fever temperature and abnormalmilk secretion. Clinical cases may be acute, where animals clearly show all the characteristic signs of inflammation and chronic, where the infection remains in a more or less quiescent state with recurrent mild to severe attacks.
Mastitis may be defined as inflammation of the mammary gland caused by specific disease producing microorganisms
Mastitis in dairy goats, like mastitis in dairy cows, is a disease of considerable economic importance. As in dairy cows, infection is usually spread from infected to non-infected susceptible animals during the milking process.
Subclinical mastitis may be defined as mammary gland infection as revealed by laboratory examination of milk samples. Clinical mastitis is characterized by signs of inflammation: swelling, pain, fever temperature and abnormal
milk secretion. Clinical cases may be acute, where animals clearly show all the characteristic signs of inflammation and chronic, where the infection remains in a more or less quiescent state with recurrent mild to severe attacks.
The most common organism involved in dairy goat mammary disease is Staphylococcus epidermitis which is commonly found on the skin of human hands and the udder skin of goats. This organism produces progressive chronic mastitis very similar to Streptococcus agalactiae infection in dairy cows. Recurrent attacks where the udder is feverish and painful; the quantity of milk secreted is curtailed and the somatic cell count is greatly elevated (see Diagnosis) depending upon the frequency and severity of attacks.Staphylococcus aureus is also an important organism involved in dairy goat mastitis. It is found in both non
- clinical and acute mastitis cases. Acute or peracute attacks are quite similar to blue bag, the common form recognized in sheep.Gangrene mastitis is not a particular "kind" of mastitis, but most often the result of the most common mastitis' causing bacteria, coagulase
- positive Staphylococcus aureus. Staph aureus can produce alpha toxin, a potent vasoconstrictor that is thought to be involved in the pathogenesis of gangrene mastitis. Other common pathogens are sometimes involved, including coagulase
- negative Staphylococci, and any number of Gram
- positive, Gram
- negative, and coliforms bugs. Clinical acute cases result when infected udders are injured and they are characterized by severe inflammation which may rapidly become gangrenous, with fever, intoxication and gross changes in milk secretion. The milk secretion of a clinical mastitis flare
- up in a gland or the whole udder may become yellow, thick and greatly reduced in quantity.In peracute cases, gangrene quickly develops, often within a few hours and the affected animal may die unless the entire gangrenous gland is surgically removed.Streptococcus agalactiae infection is often reported as a cause of dairy goat mastitis. It and other streptococci are not nearly as prevalent or economically important as they are in dairy cows.Corynebacterium pyogenes mastitis in dairy goats is characterized by the presence of firm round abscesses in the milk producing tissue. The disease is usually progressive; advanced cases of the disease reveal multiple abscess formation with nearly complete destruction of milk secreting tissue.Mycoplasma mastitis is rare in dairy goats. It may be found inanimals suffering from systemic mycoplasma infection. This form of mastitis is not rare in countries where contagious caprine pleuropneumonia occurs in goats.
Causes of mastitis in goats are:
Subclinical mastitis in goats may be identified as it is in dairy
cattle; by laboratory culture and examination of carefully collected milk samples. However, the common pathogen in goats is usually not considered pathogenic in cows. Laboratories which commonly culture cow milk for mastitis may report goat milk samples infected with Staphylococcus epidermitis as negative. That organism is not coagulase
positive or hemolytic on blood agar plate culture.
Staphylococcus aureus is readily identified by laboratory culture of milk samples. Corynebacterium pyogenes may not be detected by laboratory examination if udder lesions are few and well isolated by abscess formation.
The California Mastitis Test (CMT) and Somatic Cell Counts (SCC) of milk are useful monitoring tools to detect the presence of mastitis in the mammary glands of dairy goats.
The California Mastitis Test is a simple rapid means for detecting mammary gland infection and irritation. It has had wide acceptance and used by veterinarians and dairymen in routine mastitis prevention and control programs. There is widespread belief that a higher CMT is normal for goats than for cows. Until that argument is definitely settled, a CMT of 1 or higher should be cause for concern in goats.
Somatic Cell Counts are a more accurate measure of udder health. Healthy dairy goat herds can be expected to produce milk with a somatic cell count under 500,000. The presence of mastitis infection in dairy goat herds is reflected in bulk tank milk samples with a CMT of 1 or higher and a somatic cell count exceeding 1,000,000 cells per milliliter.
Regular use of the CMT or SCC can give both the owner and the milk consumer confidence that the milk is produced by healthy animals.
- Tachycardia, rapid pulse, high heart rate
- Anorexia, loss or decreased appetite, not nursing, off feed
- Cyanosis, blue skin or membranes
- Fever, pyrexia, hyperthermia
- Generalized weakness, paresis, paralysis
- Inability to stand, downer, prostration
- Mammary gland swelling, mass, hypertrophy udder, gynecomastia
- Reluctant to move, refusal to move
- Dullness, depression, lethargy, depressed, lethargic, listless
- Pain mammary gland, udder
- Abortion or weak newborns, stillbirth
- Agalactia, decreased, absent milk production
- Bloody milk, red, pink, brown milk
- Cold mammary gland, cool udder
- Edema of mammary gland, udder
- Firm mammary gland, hard udder
- Mastitis, abnormal milk
- Slough of mammary gland, udder
- Warm mammary gland, hot, heat, udder
- Cracked skin, fissure
- Foul odor skin, smell
- Moist skin, hair or feathers
- Skin crusts, scabs
- Skin erythema, inflammation, redness
- Skin fistula, sinus
- Skin necrosis, sloughing, gangrene
- Skin ulcer, erosion, excoriation
- Warm skin, hot, heat
Prevention and Treatment
Tender loving care may be the most important basic requirement for
mastitis prevention and treatment. Dairy goats are very sensitive,
intelligent animals. When the person milking the goat likes the animals
and handles them gently, quietly and patiently, goats willingly and
eagerly participate in the milking procedure. With ideal milking
management, goats show abundant evidence of affection for the
person doing the milking job, letting their milk down for maximum ease
and speed of milking.
Modern milking machine equipment, if properly cleaned and used,
will milk goats rapidly without injury when used by trained operators
who like the animals.
Rough hand milking which pulls on the teats and excessively strips
after milk-out can be stressful and injurious as bad machine milking.
Good hand milking requires full hand milking and no tug and pull on
Both hand and machine milking require good milking preparation -
clean dry teats and clean dry hands and/or teat cup inflations. Rough
handling, irregular milking times, overmilking or inadequate
preparation for milking all take their toll in providing stress and
injury. These directly affect mastitis resistance and susceptibility.
Mastitis in dairy goats, like mastitis in dairy cows, is rarely an
important disease in herds where animals are thoroughly prepared for
milking by massaging and washing udders. The use of a bactericidal
solution to cleanse the udder and teats also stimulates good milk
let-down. Dry the udder and teats with an individual paper towel before
milking begins. With hand milking, it is very important that milkers'
hands be thoroughly washed and dried before milking.
Milking machine teat cups should not be attached to the goat until
udder and teats are thoroughly washed and massaged, cleaned and
Hand or machine milking which is hurtful or excessive beyond normal
let-down contributes to teat end injury and the spread of mastitis from
goat to goat in the milking procedure.
This procedure has been found useful for preventing spread of
mastitis from infected to susceptible glands in dairy cow herds. It is
equally effective and useful in dairy goats. However, some teat dipping
solutions tolerated by dairy cow teats may be too irritant for dairy
goats. Teat dipping solutions should not be used for dairy goats if
they produce drying or irritation of the skin of the teats.
Dry- cow mastitis treatment udder infusion formulations are
recommended for goats which have had evidence of mastitis infection
before drying off and they may be at least as effective in preventing
mastitis attack during the dry period. A single dry- cow quarter udder
infusion dose is recommended for each udder half in the goat.
In severe acute attacks of mastitis, systemic administration of
antibiotics by intravenous or other parenteral means is indicated.
Frequent udder massage with gentle hand milking may be helpful to
relieve pressure in the affected gland to aid recovery. Strict
attention should be paid to milk witholding instructions on the label
of the product used. When mastitis cases are treated by a
veterinarian, be sure that you follow milk witholding instructions