Bimodal Milking.

It is very important to understand the need for good cow throughput but with the proper preparation and unit attachment procedures in order to promote good udder health.

These structured issues should be combined to achieve good cow throughput with excellent teat preparation and unit placement.

Poor Stimulation shows milk -letdown with no let down for 50seconds

Milking-Time Test shows bimodal milking

A milking –time test involves accurate monitoring of flow rates from individual cows throughout milking.

Milking –time test are now the standard as values of good milking health and hygiene are used on dairies to determine if there are concerns or problems with prep routines and flow rates. It can also be used to monitor flow rates from cows assigned to different milking preparation routines to determine if the routines produce different outcomes for flow rate profiles, peak flows and  bimodal milking.

On many dairies where the interval between teat prep and unit attachment is too short it is common to see bimodal let down profiles. Initially the cistern milk is removed and a certain flow rate is seen. It then reduces significantly for a period before increasing again as full let down finally ensues and alveolar milk is released by the oxytocin effect. During this low flow period there may be increased liner slips and squawks and potential unit falloffs, all of which are a concern. It also may produce teat end irritation as the liner collapses on the near empty teat for a period of time before full flow resumes.

Good preparation routines should stimulate quick milk let down and maximum peak milk flows. Based on a recent controlled research where comparisons were made with short prep routines (units attached less than 60 seconds after teat stimulation) with a normal routine (units attached 90 seconds after teat stimulation) they found bimodal milking improved. Fast milk out is valuable as long as end of milking flow rate threshold settings for unit removal are set for quick unit removal. If not, then extended unit on time with very low milk flow rates can lead to additional teat end irritation.

The above graph shows excellent and consistent milk let-down with good stimulation

The milking-time test objectively monitors milk flow-rate graphs on a select number of cows to understand what is happening. Ideally, once units are attached there should be few bi-modal flow patterns, peak flow would be reached quickly and units should be promptly removed when the low flow-rate setting are reached. Doing so improves udder health, teat-end condition and parlour throughput. low-rat