Every herdsman knows his cows are short of energy (MJ) immediately after calving, so it is common to feed a high-energy ration, but this only makes the problem worse.
The priority immediately after calving is still the need to manage the rumen for optimum acidity (pH). Even the consequent subclinical acidosis reduces total dry matter intake, when what is really required is an increasing total feed intake.
Feeding for the lactation is crucial and there are numerous herds producing 8000 litres by feeding too much dairy cake in the parlour to achieve an early peak. Such herds will also be producing low-fat milk, when there has been overwhelming evidence that cows producing low butterfat milk are not only prone to more ill-health and lameness, but are also much less feed-efficient – and, therefore, less profitable.
There is also the misleading fallacy that feeding for high-milk solids restricts liquid milk yield. The cow as a ruminant is recognised to need an accurately balanced ration at all times. Therefore, precise feed management is needed for the total lactation.
In trials in 2000, CEDAR results showed rapidly fermenting rations at 12.1ME were inferior to better-balanced rations (11.9ME) producing higher-liquid milk and milk solids, plus the profitable bonus of lower concentrate a litre. Of course your nutrition expert from your cake company will not like this proven evidence.
And although we cannot directly see the impact of subclinical acidosis, in reality the immediate impact of rapid fermentation and villi contracting is recognised by all herdsmen. At least 80% of energy must be absorbed directly by the cow as fatty acid (propionic VFA) absorbed by the extended villi through the rumen wall, for conversion by the liver into energy. When there is even one cow in 10 producing splat, then the herd has an acidosis problem.
Short-term, quick-fix feeding high-energy rations in early lactation may give the dubious satisfaction of cows peaking large daily yields at six to seven weeks, but the cow achieving lower peak yields at nine weeks from well-balanced rations, and eating higher total quantities of forage and straights, will leave higher margins and cows with less incidence of so-called production diseases.
The benefits of accurately balanced rations are gained at all levels of production.