• Most prevalent form of mastitis - causes about 70% of the losses due to mastitis.
• Causes heavy losses due to its prolonged effect throughout lactation.
• The other forms of mastitis (clinical or chronic) develop from this stage.

SYMPTOMS

• No specific symptom seen except a  slight decrease in milk production.
• Cannot be normally detected since there is no physical changes in udder or milk.

DETECTION OF SCM

• CMT - Equal quantities of milk and CMT reagent are mixed by rotating, SCM milk will form a gel. CMT reaction  may disappear within 20 seconds  , readings  must therefore be taken fast. Also check each quarter separately.
• CMT may give false positive reaction in very early (less than 10 days) lactation or when animal is almost dry.
• Strip cup test - Small flakes are present in SCM milk when viewed against a black surface, size of flakes increase with the degree of SCM.
• Paper test -  Green colour is indicative of SCM.
• Field mastitis test  - Can be carried out like CMT using using concentrated detergent solution instead of CMT reagent.

PREVENTION OF SCM

• All the points mentioned for prevention of ‘clinical mastitis’ are relevant here too.
• Test for the occurrence of SCM in your animals at least once a week.
• Each quarter should be separately tested.
• Newly purchased animals should be tested first for SCM and treated if found positive before mixing them with the herd.
• SCM positive animal (s) should always be milked at the end.
• If animals are tethered in open, change places frequently.
• Ideally, no lubricant should be used during milking. If used, it should be heated daily before use.

TREATMENT

• Consult a veterinarian for proper treatment.
• The chances of curing SCM is much higher than a clinical or chronic case.
• Timely treatment of SCM will also reduce the chances of clinical  and chronic  cases of mastitis.

                                             Treatment of SCM will greatly reduce losses