FMS Milk Quality Research; Freezing Point

Setup research

In the national survey we asked farmers, amongst others, about technical installations, measurements of milk pipes and issues related to farm management. We also asked questions about milk quality and feed quality analyses of their milk processors and feed analysis agency during the past year. For more details check the introduction.

EU regulations

The freezing point is measured to determine the addition of water to milk which can influence milk quality. EU regulations state that the freezing point of pasteurized milk may not be higher (closer to 32°F) than 31°F. The farmer may receive a lower payment, depending on local regulations. For example in the Netherlands a fine of $0.50 per 220 lbs of milk is imposed if the freezing point of raw milk is higher than 31°F. 

Technical influences

The research examined technical and farm management-related items as they both influence the freezing point. In this article we will not discuss all the technical details but will focus more on farm management related influences. Nevertheless we would like to mention that the length of milk transport lines showed a significant effect. Milk transport lines up to 49 feet show a lower freezing point 31.067°F (N=166) compared to -31.069°F (N=121) in lines longer than 49 feet.

Occupancy& milk solids influences

The research taught us that the following items impact on the freezing point and can be influenced by farm management.

Milk yield per visit: farms with a higher milk yield per visit have a lower freezing point.

• Tip: Milk yield per milking can be seen in relation to the number of refusals and free time percentage. For example, if there is a high free time percentage (20%), cows can easily access the robot and may have a high number of refusals. This means that there is a relatively high chance that these cows will be milked right at or after the time they are allowed to be milked, resulting in a minimum milking interval time. The conclusion is that the minimum yield must be closely reviewed on farms with a high percentage of free time and adjusted if necessary. The optimum is around 22lb of milk per milking; a lower milk yield per milking will have a negative effect on the freezing point and the robot’s efficiency.

Failures: thereis a correlation between fewer failures and a lower freezing point.

• Tip: Reduce the number of failures to a minimum. Not only do failures have a negative impact on the freezing point, they also increase the risk of udder health issues. So if a cow has failed, always define the reason and act accordingly to prevent another failure. Prevention is better than cure, therefore systematically shave tails and singe udders.

Fat& Protein (Lactose): There is a correlation between high fat, protein and lactose content and a lower freezing point.

• Fat & Protein Tip: The research shows us that a higher fat, protein and lactose content correlate to a lower freezing point. We also know that fat & protein are among the factors influenced by the ration. Therefore it is important to feed a well-calculated and balanced ration. Use the KPI indicator to monitor closely and consult the feed advisor if necessary. Fat and protein indications are available in T4C (versions 3.1.0.28 and higher) in combination with a MQC-2.
   
• Lactose Tip: A higher lactose level is seen in cows with a lower cell count. Research showed a percentage of 4.44% at 200.000 SCC against 4.61% at 148.000 SCC*. Ketosis also influences lactose, so prevent ketosis and make sure there is a well-balanced ration during the dry period and early lactation as there is an increased risk of ketosis during this period. Please check here for further information on Lactose and T4C.

Conclusion

On farms where the freezing point is an issue check the milk yield per visit, the number of failures and the fat & protein (lactose) figures from a farm management point of view. If changes are necessary always discuss and clarify them up front with the farmer and consult the feed advisor and/or veterinarian if necessary.

_{*Source: AgruniekRijnvallei 2013; n=375.}