Reflecting on a feed plan for autumn is a sensible strategy.
When managing beef cattle though autumn, it is important to understand the concept of different nutrients, the need for general nutrient balance, the types of feed available and their nutritional strengths and weaknesses.
The ruminant digestive system must be adapted to the feeds on offer and poor feeding practices can have significant impact on animal health and productivity.
In autumn, factors that can reduce the intake of a balanced diet, leading to production losses are:
■Limited access to feed or the amount of feed on offer.
■Environmental stress (for example, cold and chill) leading to a lower intake.
■High moisture content of (fresh) feed following rain events.
It is critical to meet the energy requirements of the animals as well as aiming to provide at least the minimum protein requirements.
Have the feed tested to ensure it has a suitable feed value.
Assess the best value source of quality grain and hay/roughage.
Introduction of new, or changing, feeds should be done over two or three weeks.
In ruminants, energy is released from plant and grain carbohydrates, fats and protein through digestion by microorganisms in the rumen.
About 75 per cent of the dry matter in plants is composed of carbohydrates, which comprise a range of compounds that serve different roles in the plant.
These components are broken down differentially in the rumen.
The energy value of a feed is usually expressed in terms of megajoules (MJ) of metabolisable energy (ME) per kilogram of dry matter (MJ ME/kg DM).
The ME is the proportion of energy in a feed that animals retain and use for maintenance and production; it is the difference between the amount of energy consumed, and the amount of energy excreted in faeces, urine and lost as methane.
Growing, late pregnancy and lactating animals have a much higher energy demand than mature or dry cattle.
Accordingly, additional energy and, sometimes, protein, are often required to balance diets for growing cattle and lactating beef cows on dried-off or rain-affected autumn pastures.
It is only after all the maintenance needs of the animals are met that energy in the feed can be used for growth, production or reproduction.
Cattle energy requirements vary with stage of production, size of the animal, and expected performance such as growth or calving and lactation.
Additional energy allowance should be made in the event of cold, chilly weather.
Planning for the feeding of stock through autumn is important in three ways — to maintain productivity in cattle, to give pastures a ‘head start’ and to ensure your financial resource is allocated efficiently.
■Information regarding feeding livestock and feed budgeting is available from an Agriculture Victoria livestock officer or your local stock nutritional adviser.
■In addition, a ‘Feed budget and rotation planner’ is available through the MLA website: www.mla.com.au/extensiontraining-and-tools/tools-calculators/feed-budget-and-rotationplanner/
livestock extension officer