A study on the nature of milk flow curve in milking cows
2009
Petkov, P., Thracian University, Stara Zagora (Bulgaria) | Pejchev, K., Thracian University, Stara Zagora (Bulgaria) | Petrov, G., Thracian University, Stara Zagora (Bulgaria)
The study included 38-cows at first, second and third lactation. These were daughters of 18 bulls and were reared in the same farm. The animals were from the Bulgarian Black-and-White breed. The study aimed to determine the nature of the milk flow curve at the evening and morning milking for 5 months since the beginning of the lactation. The dynamics of milk flow was recorded every 30 seconds from the beginning of the milking to the phase of the final milking of the animals. Each lactation was analyzed separately since the cows differed in age. The quantity of the milk yield was controlled and the effect of the milking time on the milk flow was studied. The recurrence ratio of the milk yielded was determined for each milking and each lactation month. The milk flow curve at the evening milking was steeper than that at the morning milking. After the maximum flow the curve was most constant in the 1st and 2nd month. The maximum flow in the evening milking was achieved 0.5 – 1 minute earlier than at the morning milking. For all three lactations it was most often found in the period between the 1.5th-2.5th minute. The recurrence ratios for cows at their І and ІІ lactation were from moderate to significantly high and reliable, and for the ones at the ІІІ lactation they were low and most often insignificant.
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