Early - Peak Lactation
Feeding energy dense concentrates in early-peak lactation will achieve extra peak milk production, reduce liveweight loss, and provide reproductive and animal health benefits
Cow energy requirements are highest in the first 3-12 weeks after calving. In early-peak lactation all body tissues are growing with udder development important. Milk production and hence energy demand peaks at about 6 weeks post calving, whilst appetite peaks around 10 weeks post-calving. During this period energy requirements are often in excess to pasture availability as cows calve ahead of the spring flush.
Bulky low dry matter feeds such as grass or silage physically restrict feed intake during this period as the cow can only fit a certain quantity into her rumen. If spring pasture and a concentrate both had 11 MJ ME per kg of dry matter, a cow needs to consume five times as much fresh pasture as concentrate to get the same energy.
Energy is virtually always limiting in spring under NZ conditions. The difference between feed intake and demand in high genetic merit cows may be met by liveweight loss – cows milking ‘off their backs’. This liveweight loss impacts cow health, cow fertility and milk productivity.
NRG and Breakfeed Advantage are the best supplements to lush spring pasture, as they are palatable and high in dry matter. As a cow can only eat 3-4% of liveweight per day, if cows are not supplemented with an energy dense concentrate when feed demands are highest, milk production can be suppressed and liveweight loss will result.
Supplementing with concentrates will provide both milk production responses and an improvement in cow condition. The impact of feeding 1kg of feed concentrate in early lactation is 0.5-1 litre of milk. Studies have shown further benefits are provided longer term through improved cow condition, health, and reproduction. Research shows an extra 1 litre milk at peak lactation means a potential extra 140-170 litres during the whole lactation (SIDE Conference 2002).
When feeding a concentrate and minimising weight loss the period from calving to first heat is reduced. This results in a more condensed calving pattern with more days in milk the following year. This means fewer empty cows and fewer calves induced, reducing involuntary culling.
• Extra 6 days milk production from 20% herd in spring = $15 per cow
• 3% less wastage at $1000 per heifer raised = $30 per cow
• Improved animal health benefits = $40 per cow
Feeding 1kg concentrate per day from calving to peak lactation returns $85 per cow, for a cost of around $50. In addition, each extra litre of milk at peak lactation could mean another 170 litres of milk or $60 per cow per year.
