‘Individual’ treatment can help to maintain dairy cows’ daily energy status
Take Home Message: Feed cows on an individual basis to help reduce negative energy balance in early lactation.
Manipulation of individual cow diets in early lactation may help to maintain daily energy status. That was the conclusion of a study, carried out by a team of researchers at Hillsborough’s AFBI, to evaluate the effect of a range of nutritional strategies on milk production, energy balance and efficiency of nitrogen use in early lactation.
“We also found that reducing the crude protein content of the diet, improved nitrogen utilisation with no significant reduction on milk yield or effect on milk composition,” Ryan Law told delegates at this year’s British Society of Animal Science’s annual conference. “But daily energy status was reduced.”
He explained that improving the sustainability and overall longevity and health of modern Holstein Friesian dairy cattle was essential in order to maintain overall farm profitability.
“Prolonged negative energy balance in early lactation can result in metabolic stress, as well as long term problems with fertility,” said Dr Law.
“In addition, maximising the efficiency of nitrogen utilisation by strategies such as reducing the crude protein content of the diet is crucial when trying to minimise the environmental impact of dairying.”
A total of 96 dairy cows were allocated to one of four dietary treatments immediately after calving. All diets were offered as a TMR and the ‘control’ diet was formulated to supply 200g of starch per kilogram of DM with an overall crude protein content of 175g/kgDM.
“And we found that dry matter intake, milk yield, milk composition and liveweight change (from calving to 210 days) were not significantly different between treatments,” said Dr Law.
“But daily energy status was affected by treatment, with the individual cow treatment having the highest average daily energy status compared to the other three treatments
“In addition, efficiency of nitrogen utilisation was significantly different between treatments with the low protein diet having the most efficient utilisation of nitrogen,” he added.
Presented to the British Society of Animal Science Annual Meeting, March 30 to April 1, 2009, Southport, UK.
Full details: Young FJ, Law RA, Gilmore HS, Patterson DC, Wylie ARG, Mayne CS: “An evaluation of the effect of nutritional strategy in early lactation on performance and energy status of Holstein Friesian dairy cows.”
Summary (pdf) Presentation_079young (pdf)
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