Pioneer Technical Insight

 312

Maize silage is an excellent feed option for all classes of beef cattle. It may be included in growing rations, fed to lactating cows or used to maintain breeding stock.

1. High yields
   The maize plant is an efficient converter of sunlight, nutrients and water into plant material. It has the ability to produce high drymatter yields and performs well under dry conditions.
2. Low cost per unit of drymatter
   The high production capability of maize means that most farmers can grow crops of maize silage that yield 18 - 26 tDM/ha for 15 - 21 c/kgDM .
3. Feed when required
   Provided that it has been compacted well and sealed, a stack of maize silage will keep for several seasons if necessary. Maize silage therefore gives increased flexibility when compared to other summer crop options which must be grazed when they are ready.
4. High energy content
   In good quality maize silage, more than half of the total drymatter yield is in the form of high energy maize grain. This contributes to the high level of energy in maize silage compared to more traditional conserved feeds (Table 1).
5. High palatability
   Good quality maize silage is extremely palatable, increasing animal intakes and liveweight gains and decreasing wastage.

The approximate energy requirements for growing cattle (megajoules of metabolisable energy per day (MJME/day)) are shown in Table 2 below.

¹Adapted from Livestock Feeding on Pasture (NZ Society of Animal Production, 1987). Add 5% for heifers and deduct 5% for bulls.

The approximate maintenance energy requirements only of adult cattle are shown in Table 3.

² From Livestock Feeding on Pasture (NZ Society of Animal Production, 1987).

The approximate dietary protein requirements for a range of animal liveweights and rate of gains are shown in Table 4.

Maize silage can be used as a supplement or as the major part of a ration for most classes of beef cattle. The major limitation of maize silage is its low crude protein content (7-9%). This can be overcome by feeding maize silage in conjunction with a protein source (e.g. leafy pasture, good quality pasture silage, lucerne or lucerne silage, a high protein forage crop or a protein concentrate). In general the younger the animal and the faster its liveweight gain, the higher the crude protein requirement. Lactating animals also have higher protein requirements.

Urea may be an option for lifting the crude protein content of maize silage based diets. Urea is not a protein but the bacteria in the rumen can turn the nitrogen that it supplies into protein. The amount of urea that is required will depend upon the animal’s protein requirement and the level of crude protein in the animal’s diet.

Urea is toxic and can induce poisoning unless the feeding rate is correct and feeding guidelines are adhered to. Contact your local Pioneer Forage Specialist for more information.