Feed conversion efficiency
With feed costs being such a large proportion of variable and total costs on a dairy farm, it is important to measure the efficiency with which feed is converted into milk.
Feed Conversion Efficiency (FCE) is a measure of the kilograms of energy-corrected milk or grams of fat plus protein produced per kilogram of dry matter intake. In the Pasture Consumption and Feed Conversion Efficiency Calculator, FCE is calculated over an annual period - and therefore includes dry matter intake of the milking cows when they are dry, rather than their FCE only during lactation.
Dairy Australia's Grains2Milk project has developed annual milker Feed Conversion Efficiency targets based on 5 main feeding systems common to the Australian dairy industry. The five main feeding systems are :
1. Low bail system
Pasture plus other forages plus low grain/concentrate feeding in the bail (up to 1.0 t grain/concentrates per cow fed in the bail)
2. Moderate-High bail system.
Pasture plus other forages plus moderate-high grain/concentrate feeding in the bail (more than 1.0 t grain/concentrates per cow fed in the bail)
3. Partial mixed ration (PMR)
Pasture plus partial mixed ration ± grain/concentrate fed in the bail (pasture grazed for most or all of the year plus partial mixed ration on feed pad ± grain/concentrates per cow fed in bail)
4. Hybrid system
Pasture grazed for less than nine months per year plus partial mixed ration on feed pad ± grain/concentrates fed in bail
5. Total Mixed Ration (TMR) system
Zero grazing. Cows housed and fed total mixed ration.
Achievable annual FCE targets for milking cows for the 5 different feeding systems are expressed in terms of litres of energy-corrected milk (standardized for protein and fat concentrations) or grams of milk solids per kilogram of feed dry matter. Annual milker feed conversion targets developed by the Grains2Milk program have been set at :
It is important to note that the FCE values calculated in the Pasture Consumption and Feed Conversion Calculator are only a guide.
This is because the Pasture Consumption and Feed Conversion Efficiency Calculator uses a 'back-calculation' approach to estimate the dry matter intake of pasture. There are three steps to the calculation.
- First, an estimate is made of the metabolisable energy required for milk production, pregnancy, walking to and from the dairy, grazing, maintenance and growth and liveweight changes throughout the year (A), based on standardised equations published in the Australian Feeding Standards.
- Next, the user is asked to enter how much energy has been supplied by 'brought-in' supplements (B).
- Third, by difference, the amount of pasture consumed can be estimated as (A - B) = C.
Thus, dry matter intake and production estimates in this program are strongly correlated and dependent on each other. Results should be interpreted with caution and should not be used for 'between farm' comparisons.
FCE should always be used in conjunction with other farm physical performance measures, and financial performance measures such as annual operating profit and return on assets.