Use milk records to boost fresh calvers

NMR and CIS milk records contains a wealth of information to help you improve fresh cow performance. UFAC-UK’s David Bonsall considers how they can unlock the key to a more productive lactation.

In the past, dairy farmers have often relied on measures like milk yield results and whether cows are losing weight or not as the best guide of how fresh calvers are performing. But now, taking a look at milk records data at the first two recordings can shine a spotlight on how well they are really doing and allow action to be taken to correct any problems. There are four main areas to look at.

Mono-unsaturated fats in milk

High levels of mono-unsaturated fats can suggest cows are losing too much body fat. Anything above 30% of milk fat as mono-unsaturates is an indicator that body weight loss is an issue. Because cows carry large amounts of fat in the body cavity which can be mobilised, they can be losing weight without actually losing visible condition.

Also look at levels of C18:1 oleic acid. Levels above 22-25% suggest a real problem. This is one of the first fats mobilised and it is found in large quantities in the foot pad. If cows are mobilising C18:1 they will be predisposed to lameness, particularly solar ulcers.

If high mono-unsaturates are a problem, look at the energy density in the diet and monitor intakes as cows probably aren’t migrated onto the milking cow diet effectively. Also check they have adequate feed space – at least 70cm/cow.

Short chain fatty acids

These are the fatty acids produced in the rumen and indicate how the rumen is performing. Levels below 9% point to problems with rumen function and how well cows are making the change from the transition to milking cow diet.

If you see low short chain fatty acid levels take a close look at the diet and particularly whether cows are getting sufficient structural effective fibre to support rumen function. It might be that the diet needs more fibre or that cows are sorting the diet, two things we can confirm by sieving the diet.

Diet sorting can also lead to too much starch in the diet, which can upset the balance of rumen fermentation.

Fat to Protein ratio

Typically you should see a ratio of 1.3:1. A ratio below 1:1, indicates cows could be suffering with SARA while a ratio of over 1.5:1, particularly in early lactation, could indicate cows have ketosis.

Lactose

Lactose can tell us a lot about the energy status of the cow and particularly the levels of glucogenic energy in the diet. Glucose is essential for milk production and lactose levels below 4.5% indicate that cows may be short of glucogenic energy, in which case look closely at the balance of energy sources in the diet. Low lactose can also be caused by cows being away from food too long. A mix of high and low lactose values from cows on the same diet is a good sign of diet sorting.

By looking at milk records in a bit more depth, you will be able to get cows settled into a more profitable lactation.