Feed Focus: Achieving a successful transition

A successful transition cow system will result in giving the cow the best possible start to what is hopefully a profitable lactation, however significant health and production issues can still occur which often stem from deficiencies occurring either during the dry period or immediate fresh cow period.  Adam Clay from NWF Agriculture details some of the key parameters to add focus in achieving a successful transition.

• Late lactation body condition score
  • Sources have shown overweight cows at the point of drying off and through the dry period can have reduced dry matter intake through the dry period. This could lead to reduced intakes immediately post calving which in turn can affect metabolic disease. Ensure cows are dried off in the correct condition, ideally 2.75 – 3.25.
• Far off dry period
  • The far-off dry period is often overlooked, and cows put out to pasture on varying quality grasses. Over feeding energy through that period can significantly impact metabolic disease post calving (Janovick-Guretzky and Drackley, 2006). Typically, energy requirements for this group are approx. 15% bodyweight (BCS depending) which equates to 100MJ for a 675kg cow. Whilst dry matter intake should remain high to maintain high rumen volume, be aware of overfeeding energy.
• Dry matter intake and close up period
  • This can prove to be the difficult point to transition management. High intakes pre-calving can help high (forage) intakes post calving, and that must always be our objective through transition to minimize negative energy balance in early lactation. However high pre-calving energy intakes can increase metabolic disease, therefore dry cow diets often need to be balanced using a good quality, low energy dense forage. Variable by breed and animal size, dry matter intakes should typically range from 12 – 14kg/h/d for far off dry cows and 10 – 12kg/h/d for close up dry cows where energy levels should be approx. 20% bodyweight.
• Nutritional parameters
  • I have focused on energy so far, but protein is as equally important. Dietary protein can have a significant impact on dry matter intake, especially if the transition diet is largely made up of structural fibre, such as straw or dry hay. Far of dry cow diets should be 13 – 14% protein and close up dry cow diets closer to 12 – 13% protein. Starch levels are encouraged to be up closer to 10% particularly in the close up dry period as this can help the rumen microbes become accustomed and prepared for a more intensive lactation diet. However practically such starch levels in transition are very difficult to achieve, so be prepared to react if cows do not produce enough colostrum or dung becomes very stiff.
• • Minerals are merely a component of the diet and should be considered as important to balance as energy and protein. A standard transition cow mineral should adequately balance a diet, but certain levels may have to have closer attention paid. Whilst milk fever is a clinical deficiency of calcium post calving, feeding too much calcium pre-calving can cause more milk fever. Aim to implement a mineral balance with calcium levels as close to 30g/h/d as possible. Magnesium is an essential element for transporting calcium and can help to reduce milk fevers, levels of up to 50g/h/d should be targeted, possibly slightly higher when potassium levels are high.
• Metabolic disease
  • Metabolic disease is summarised as a chemical reaction which alters normal metabolic function. In dairy cows this is seen as an imbalance of energy (ketosis), a reduced absorption of a mineral (calcium, magnesium or phosphorous deficiency) or a suppression of the immunity (uterine infection and/or retained cleansing). These metabolic diseases can often be the outcome from a clinical or sub clinical case of milk fever. Whilst considering all the points previously mentioned, DCAB (Dietary Cation Anion Balance) can be an effective method of reducing the occurrence of milk fever. By applying a diet with a strong negative DCAB in the close- up period, balance can be restored to aid the cows’ own ability to utilise her vast calcium reserves.
• Fresh Cow
  • I strongly advocate a fresh cow group, if nothing else this group can give cows more space and comfort to recover after calving. Key points
    • Cows stay in the group from 5 – 21 days post calving
    • Once cows are fully cleansed, eating and drinking well, re-hydrated, temperature checked and milking well, they can enter the main group
    • Use the same milking cow diet with added structural fibre (to help fill the cow up) and added energy supplements where appropriate
    • Always use a fresh cow re-hydration drink to encourage her to eat and drink as soon as possible, as well as delivering an energy boost.

Transition cow management should be simple and consistent, to deliver a stress-free calving period and give the cow the best possible start to lactation. Once an effective program is put in place, farmers and advisors can monitor performance to determine any changes that need to be employed.

www.nwfagriculture.co.uk