Days 231 – 300 (Lengthen lactation before doing off)
Boost nutrition to lengthen lactation while bringing the herd up to good body condition prior to drying-off. Address mineral deficiencies and give nutrients for foetal development.
Heading into this stage of the season, pasture quality improves due to an improvement in neutral detergent fibre (NDF) digestibility. Try to hold dry matter intake (DMI) at levels around 3.5% of bodyweight per cow per day. Forage NDF, hormonal adaptations and metabolic feedback signals will all have a significant bearing on the ability to achieve this level of intake.
WHAT YOUR COW NEEDS
Metabolisable protein content of the total ration can be manipulated during late lactation in order to meet body condition score (BCS) targets. By reducing metabolisable protein (MP) supply relative to total energy consumption, we can effectively manipulate the metabolism of the cow to partition more energy towards body reserves rather than towards milk solids production. Forages such as maize silage fit this scenario nicely due to its inherent low protein, high carbohydrate feed value. Products with higher fat values can also assist as we add a source of energy that does not stimulate blood glucose and insulin responses that drive milk production. MP requirements for weight gain must be catered for in the total ration: cows producing >1.5kg MS and gaining 0.5kg of liveweight daily will need around 1,930 grams MP supply daily.
Continuing to provide the cow with energy by carbohydrates remains important through this stage of lactation. Often sugars available in pasture are lower, so supplementing the diet with molasses to meet a dietary requirement of 10% is helpful. Providing a starch source to help meet the cow’s energy demands can provide balance in seasons of higher pasture NDF (40 – 45%).
Vitamins and minerals should not be overlooked, particularly for higher producing cows. Providing good sources of calcium and magnesium for bone remodelling and phosphate for skeletal and energy enzymes are important. This will be paid back in kind during the next calving period.
Delivering the best nutrient mix
To provide a balance between energy and DMI, TopCow® Seasonal is an excellent late lactation option. While extending lactation, it cannot be emphasised enough that this is also the time where preparation for the next lactation begins. It is much more efficient to improve a cow’s body condition while she is still lactating.
TopCow® EziMin 350 blend is designed to be used at 200 – 350 g/cow/day for cows producing up to 500 kg MS/annum.
TopCow® Boost and TopCow® Seasonal usage rates will vary according to forage availability, breed of cow, stage of lactation and milk solids production.
Please contact your Ingham Dairy Nutrition Specialist to discuss your herd’s specific nutrient requirements.