Using lick blocks is a popular way of supplying protein to cattle. Blocks are easy to use and with plentiful supplies of dry feed can be effective.

Commercial protein blocks are expensive and other, cheaper alternatives are available. It may be cheaper and more effective to feed small amounts of high-quality protein supplements directly to cattle.

Home-made protein blocks use urea and protein meal to supply rumen protein to the animal. Urea blocks need to be introduced so that cattle gradually increase their urea intake.

Start with 2% blocks at first, then introduce 5% and eventually 10% urea mix blocks after several weeks. Carefully weigh all ingredients, mix them thoroughly with a cement mixer and pour into moulds.

Basic mixes

The ingredients

Molasses

Molasses is used to dissolve urea and salt and to encourage stock to eat the block. Molasses contain high levels of sulphur. It should be heated before mixing and then the dry ingredients added to it.

Protein meal

The best protein meals are cottonseed meal and Nor-Pro® (around 41% CP). Other sources include lupins, rapeseed meal and canola meal.

Urea

Urea provides a source of nitrogen which cattle can convert into usable protein. For maximum effect, it must be consumed daily, so don’t let blocks run out; keep them constantly available.

Consumption of more than 60 g of urea per head per day can be dangerous, particularly if blocks are rained on (urea dissolves into the rainwater and the cattle drink this), or if they crumble and are eaten in lumps.  Use stockfeed grade urea only.

Cement

Cement supplies calcium and acts as a block hardener.

Salt

Salt may be essential when scrub feeding or feeding on sorghum stubble. It acts as both an attractant and an appetite limiter.

Phosphorus sources

The following products provide sources of phosphorus: 

•    Kynofos 21® (21% phosphorus) 

•    Biofos® (21% P) 

•    Dicalcium phosphate (18% P) 

•    Palaphos® (15.3% P) 

Do not use fertilisers like superphosphate, MAP (monoammonium phosphate — Starter 12) or DAP (diammonium phosphate) as phosphorus sources as they are now unsuitable for animal feeding. They contain fluorine at levels that can cause fluorosis if fed to stock for an extended period.

Handy hints

•    Allow 7–10 days for blocks to harden.  

Successful moulds include cardboard boxes and timber frames. 

•    Coat the inside of moulds and mixer with some oil (avoid using sump oil from petrol engines because it may contain lead).  

•    Large mixers mix more thoroughly than small mixers.  

•    Make sure urea is dissolved in molasses or water first. It is important to thoroughly mix the required amount of urea into the molasses first, otherwise poisoning can occur.  

•    Experiment with different combinations while keeping in mind the warnings about high levels (over 10% by weight) of urea.  

•    It is not possible to make a home-made block with a protein content above 40% unless urea is included in the ingredient mix. This is also true of manufactured blocks.  

•    Drum molasses consistency can vary as a result of different molasses sources.