New analysis tool measures feed conversion efficiency

Optimal feed conversion efficiency is essential on any dairy farming system. How can farmers measure and manage this? Gemma Mackenzie finds out.

Getting the most bang for your buck out of feed is the key to a profitable dairy system, and understanding feed conversion efficiency could help dairy farmers boost their returns.

A new milk analysis tool not only measures the efficiency in which cows convert feed into milk, but the level of saturated fat present in the milk and methane output from the herd.

The Visiolac tool – developed by BOCM PAULS – takes information from a bulk milk sample analysed by NML, and alongside figures on average milk output and days in milk, determines the level of Omega 3 in the milk and the amount of energy wasted as methane.

It identifies key factors impacting on feed efficiency, including: efficiency of energy, protein and fibre use, risk of acidosis, and herd health and fertility.

Speaking at a press launch, the company’s head of rumen development, Wyn Morris, said the ability to measure saturated fats could allow tweaking in the diet to reduce saturated fat production in the cow, and free up more energy for milk production and fertility.

Fifty percent of milk fat is produced from the end products of rumen fermentation, and 50% comes directly from dietary sources or body condition.

He added: “Knowledge about the relationship between certain fatty acids, and the ability to measure these in milk provides us with an insight into the efficiency of rumen fermentation. Once they can be measured, they can then be adjusted through the diet.”

New feed value

The analysis tool is designed to complement a new feed value index – it3 – which gives feedstuffs, including forages, a value based on the balance of Omega 6 and Omega 3 fatty acids contained within the feedstuffs. Traditionally, feeds such as grass and linseed are high in Omega 3, and feeds such as soya and sunflower are high in Omega 6.

A diet with an it3 value of 40-60 will result in improved rumen health and fertility, while a ration with an it3 value of 80-100 will boost yields, and one with an it3 value of 120-140 will also result in reduced methane production.

Ruminant product manager Nick Berni said the index was developed to aid the formulation of rations, which would “restore the natural balance between Omega 3 and Omega 6, from when cows used to eat grass more”.

He added: “There are going to be different times of the year when it3 will come into play, and we are now in a position to constantly monitor diets and change them accordingly. By steadily increasing the it3 value of the diet, we are able to get an increase in milk production.”

He said it3 rationing was more relevant in the autumn and winter months, once the cows had come in from spring and summer grazing.

Farmers are recommended to get a milk analysis test done fortnightly, and once the diet has been formulated, monthly analysis tests are suitable thereafter.

Trials of the analysis tool on more than 100 pilot farms have found an average increase in the feed-to-milk ratio of 0.1 litres of milk per kilo of feed (based on an average starting point of 1.2 litres of milk per kilo of feed), which equates to between 40-50 pence a cow a day. Taking a midpoint improvement of 45p, this would result in nearly £1,400 extra profit a month for every 100 cows.


• Lactation ration has an it3 value of 78 and consists of grazed grass, grass silage, wholecrop silage, maize silage, 0.7kg straw, 7.5k custom blend, and water. The cows are also fed an 18% TDF dairy cake in the milking parlour.

• Dry cow ration has an it3 value of 24 and consists of 17.8kg grass silage, 3.5kg maize, 4.5kg straw, dry cow nuts, water, and magnesium chloride to balance forage minerals as required.

Case study: Alan Winstanley of Highfields Farm, Audlem, Crewe

Alan Winstanley of Highfields Farm, Audlem, Crewe, has increased his milk yield by 1.2kg a cow a day following ration tweaking and diet reformulation with the aid of the new milk analysis tool and it3 rationing system.

“There have been marked improvements in yield and health since using the diagnostic tool Visiolac. We are able to adjust raw materials to balance my forages before things go wrong. One obvious sign of the effects it has are shiny, healthy coats – the black is black and the white is white,” said Mr Winstanley.

He added: “The performance of the dry cows has improved significantly since moving onto the single dry cow diet. There are fewer retained cleansings, displaced abomasums have significantly reduced and the cows are in a much better condition to go into the milking herd.”

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