2. INTRODUCTION
• Inflammation of the udder/mammary gland
• Almost always due to infection by micro-organisms
• Affects different animal species (e.g. cattle, goats, sheep, buffalo,
camels) and humans
3. INTRODUCTION
• Mastitis is the inflammation of the mammary gland and udder tiisue in
animal and it is a major endemic disease of dairy cattle.
• It usually occurs as an immune response to bacterial invasion of teat
canal by variety of bacterial sources present on the farm and can also
occur as a result of chemical, mechanical or thermal injury to the
udder.
• Milk secreting tissues and various ducts throughout the udder can be
damaged by bacterial toxins and sometimes permanent damage to the
udder occurs.
• Once udder become infected with bacterial infection its said that its
never become free of the organism.
4. AETIOLOGY
• Caused by infectious micro-organisms
• Bacteria
• Yeast/fungi e.g. Candida spp, Aspergillus fumigatus, Cryptococcus neoformans
• Algae e.g. ??? (Prototheca)
• Common bacteria:
• Gram +ve: Staphylococcus (S. aureus), Streptococcus (S. agalactiae, S. dysgalactiae,
S. uberis)
• Gram –ve: Coliforms (E.coli, Enterobacter spp, Pseudomonas spp. Klebsiella spp etc.)
• Others: Arcanobacter pyogenes (Old names:Corynebacterium pyogenes/Actinomyces
pyogenes) , Mycoplasma spp., Mycobacterium spp, Brucella spp etc.)
5.
6.
7. CLASSIFICATION
CRITERIA EXAMPLES
1.AETIOLOGY -Staphylococcal-, Streptococcal-,
coliform mastitis
2.SEVERITY, ONSET &
STAGE OF CLINICAL
DISEASE
-Peracute, -Acute, -Subacute, -Chronic
3.CLINICAL
MANIFESTATION (I.e. obvious
changes of the udder/milk)
-Clinical Vs Subclinical
4.MODE OF TRANSMISSION -Contagious
-Environmental
-Minor
8. PREDISPOSING FACTORS
• Poor milking hygiene (utensils, milker, surroundings)
• Teat injuries & sores
• Incomplete emptying of the udder during milking
• Environmental population of pathogens
• Milking machine faults e.g. vacuum pressure, pulsation ratio etc.
9. PATHOGENESIS
• Coliforms: Clinical signs mediated through ENDOTOXAEMIA
(endotoxin released from dead bacteria), hence usually associated
with systemic signs
• Contagious: Infection elicits immunological response ( PMNs),
tendency of walling off leading to Chronic infection
Some organisms e.g. S.aureus produce toxin gangrene;
15. EPIDEMIOLOGY: MODE OF TRANSMISSION
• Contagious bacteria (S. aureus, S.agalactiae, S.dysgalactiae)
present in infected cows, therefore mastitis is transmitted from
COW to COW during milking
• Environmental bacteria (Coliforms, S. uberis) present in the
Environment, therefore mastitis is transmitted from
ENVIRONMENT to COWS between milkings
16. TRANSMISSION OF MASTITIS
• Herd to herd
• * purchasing an infected cow
• * purchasing a suckling calf
• * milker working on more than one farm
• * sharing equipment with another farm
• Cow to Cow/ Cow or Quarter to Quarter
• * Calves suckling
• * Milker hands
• * Cloths used for washing or drying
• * stripping mastitic milk onto floor of banda
• * dirty teat dips or intramammary syringes
• * dirty teat lubricant
17. EPIDEMIOLOGY: PREVALENCE & GEOGRAPHICAL DISTRIBUTION
• A Worldwide problem (dairy industry)
• Developing world:prevalence Contagious
• Developed world: prevalence Environmental
• In Tanzania:
• Clinical mastitis: Incidence risk 1.5-3.2 cases/100 cows/year
• Subclinical (CMT): 60-80% of cows
• Common isolates: S. aureus, S.epidermidis, coliforms, yeasts
18. CLINICAL SIGNS
• I. CLINICAL MASTITIS
• This form is associated with classical signs of
inflammation which are subdivided into:
• A. Changes of the udder
• Hot to touch
• Painful (kick, reduced milk production)
• Skin colour (red, blue e.g. gangrenous
staphylococcal mastitis)
• Swollen quarter (asymmetry of the
udder) sometimes
• Atrophy (hard, lumpy, scars, shrunken)
• Blind teat(s)
20. I. CLINICAL MASTITIS (CONT’D)
• B. Changes of the milk
• May be associated with presence of (in the milk):
• flakes and clots
• Blood
• pus
21. II. SUBCLINICAL MASTITIS
• The udder is normal and milk looks normal
• However,
i)There is chronic loss of milk production not explained
by other reasons e.g management, other diseases
ii)Presence of somatic cells (epithelial and
inflammatory/leucocytes cells) in milk is a good
indicator of this form
iii)Bacteria may be present in milk.
This form is not normally recognised by farmer (has
hidden effects), though it has higher prevalence than
clinical mastitis.
23. DIAGNOSIS OF MASTITIS
• I. CLINICAL
Based on history and clinical signs (changes of the udder
and in the milk)
Should be supported by bacteriology (isolation and
identification of causative agent).
24. II. SUBCLINICAL MASTITIS
• A) History of reduced milk
• B) Measurement of somatic cells which can be:
• I) Indirect tests such as
California Mastitis Test (CMT)
Whiteside test
Litmus paper
• II) Direct Cell Counts
Using an electronic counter (e.g. Direct Microscopic Somatic Cell
Counting (DMSCC); Coulter Counter, Fossomatic): gives exact
number of cells per ml of milk.
• C) Bacteriology
D) Other tests
• Milk ELISA e.g. ProStaph (detects S.aureus antibodies in milk)
• Milk electrical conductivity test: Mastitic milk has higher
electrical conductivity (measured by sensors) due to increased
Na+ and Cl- ions.
26. IMPORTANCE OF MASTITIS
DIRECT COSTS INDIRECT COSTS
1. Discarded milk
2. Drug and veterinary
costs
3. Death of sick animals
(acute form)
1. Decreased milk yield (udder damage & subclinical
mastitis)
2. Extra labor involved in treating and nursing sick
animals
3. Higher culling and replacement rates leading to loss
of genetic potential
4. Decreased milk quality
5. Penalties due to increased SCC
