ABSTRACT
Effect of addition of newly drawn fresh milk of consecutive milkings on growth of Staphylococcus aureus , Staphylococcus epidermidis , Streptococcus agalactiae , Streptococcus dysgalactiae , and Streptococcus uberis in milk held at fluctuating temperatures of a farm bulk tank for 48 h was studied. There was a statistically insignificant effect of the addition of newly drawn fresh milk of consecutive milkings on the growth rate of S. aureus , S. epidermidis , S. agalactiae and S. uberis but there was a significant (p<0.001) growth enhancing effect on S. dysgalactiae . However, all the bacteria grew significantly (p< 0.001) in milk held at fluctuating temperatures of farm bulk tank for 48 h.
ABSTRACT
Temperature fluctuation of farm bulk tank milk was simulated in the laboratory. Temperature fluctuations of bulk tank milk on 8 farms were recorded for a week period. The median of the temperature rise and fall at each milking was used as the basis to simulate the fluctuating temperature in the laboratory. A 50-gal capacity aquarium kept in a walk in cooler set at 2°C with proper amounts of 37°C water added at the desired intervals was used to simulate a bulk tank. The recording of temperature fluctuations in farm bulk tanks and the simulated bulk tank in the laboratory were identical.
