Generally, pseudomonas organisms are not responsive to antibiotic therapy. Bacillus organisms are found throughout the environment, especially on soil, dust particles and often times on poorly sanitized milking and cleaning equipment. Bacillus bacteria are in a group known as thermodurics and are capable of adversely affecting milk quality. These organisms are capable of surviving pasteurization temperatures. The presence of these bacteria in milk are often used as indicators of the level of sanitation on the farm.
Infection normally is associated with the use of contaminated syringes, canulas or antibiotics.
Certain yeast organisms are found in the soil, bird feces and general barn environment. May be transmitted during milking via inflations. Treatment is usually not necessary as most infections are eliminated spontaneously. Frequent milkout may be helpful. Milk infected cows last and cull if quarter does not recover.