Lower North Island farmers “cautiously optimistic” heading into winter – DairyNZ
Cautiously optimistic is how DairyNZ's regional manager for the lower North Island, Mark Laurence describes the mood of farmers in his patch.
Liquid animal feed supplier Agrifeeds says the three-four week period prior to calving is when the rumen is adapting to a milking diet and the cow is preparing for calving and milking.
“Done properly, transition management improves cow performance in a number of ways, but essentially it sets the appetite ceiling for the pending lactation,” says Andrew Oakley, Agrifeeds technical manager.
“The cow responds with reduced metabolic issues and increased dry matter intake and is more likely to achieve target peak appetite and maximum production,” says Oakley. Following some basic steps helps minimise the negative effects clinical and sub-clinical milk fever has on herd productivity and profitability, he says.
The principle aims of a good transition diet are to encourage a trouble free calving to ensure a healthy calf and cow, plus eliminate all preventable primary and secondary metabolic diseases. Done properly the net effect of a successful transition diet is an increase in DMI, which improves the overall nutrient intake. This will minimise weight loss with an opportunity to achieve milk production targets.
“There are real productive and reproductive gains to be made from adopting a well-managed transition diet. Ultimately, the cow must be able to maximise and maintain her appetite and feed intakes so the rumen muscles and microflora are properly prepared to cope with lactation diets.”
Oakley also says rumen adaptation requires a minimum of three-four weeks to properly prepare the rumen microbes for the type of feed being offered post calving, hence the need to introduce the lactating diet pre-calving.
“A good transition diet provides a palatable, high-energy mix as well as low dietary cationic anionic difference (DCAD) minerals, plus a good mix of effective fibre and fermentable energy.
Another transition alternative is to feed Rumag300 to provide a blend of molasses, magnesium chloride and Rumensin, which aids in the control of ketosis at calving while ensuring energy is optimised for late foetal development and colostrum production.”
As another transition diet option, Oakley also suggests using Himag, which is a molasses and magnesium chloride blend with a low DCAD and is ideal for cows on transition diets.
Adding a low DCAD mineral mix such as NutriMin Springer Cow Balancer in either Rumag300 or Himag, plus a good mix of effective fibre and fermentable energy, will help stretch the rumen, maintain and encourage rumen capacity and cud chewing before and after calving and provide the cow with the necessary negative DCAD mineral balance pre-calving to help prevent metabolic health issues.
Also, Oakley says it is important to calculate the cost of milk fever in a herd.
“Milk fever may only represent a fraction of the total losses associated with the transition period and calving, but it gives some compelling reasons to want to change.
“In New Zealand herds, 2-30% of cows can go down with milk fever. At a cost of $1500 per cow, allowing for treatment, and in a 500 cow herd, lost production can be [at least] $200,000. With those figures, it’s worth investigating a good transition management programme,” he says.
