Rayner Reckons

Jan 17

Using Scrub as a Livestock Feed

Posted on Thursday, January 17, 2019

The search for roughage during a drought challenges many producers.  Over many years, scrub and some native trees have become a ‘go to’ for producers seeking an alternative and cheap source of feed.  

 

Many people have used scrub very successfully as part of their drought programs. However there are equally many occasions where results have been disappointing or have actually increased problems within the livestock program.

 

Image: ABC New England

So, just how good is scrub?  I know many people will swear to the value of species such as Kurrajongs, Wilga or Native Apple.  Mulga is an important species in the inland parts of the country.  

 

However as with any feeding program, it’s never really that simple!

 

As can be seen in the table above, there is a fair bit of variation in the nutritional ranges of commonly fed species.  Most species have an energy range of 7.5 MJ / Kg to 10.5MJ /kg. However in general the average is around 8.5MJ.  In general its fair to say that the best-case scenario for scrub is that it is the equivalent of average quality hay.  At these levels you really only expect scrub to provide maintenance levels of energy, provided your animals can eat enough each day!


The limitation for many scrub feeds is the level of Crude Protein (CP%). Many of the feeds that have been tested only provide enough CP to meet the maintenance requirements for dry animals. In practice this really means that if you are feeding to animals that are growing, pregnant or lactating, you will have to use a suitable protein supplement to meet these animals daily needs.

 

Not all stock will take to scrub.  And not all scrub is as palatable as you might expect.  It is important to use some local knowledge when looking at including scrub in your rations.

 

If you do start to use scrub, there are a few things to remember.  Its important to try to use scrub that has a fair bit of leaf.  Increasing twigs and small branches reduces animals overall intake of energy and protein. It also leads to risks of rumen impaction.

 

When working with producers who have had scrub in their programs, I’ve seen some useful tips.  To educate your stock to scrub, start with small amounts close to watering points and stock camps.  If needed you can spray a water molasses mix (2 parts molasses to 1 part water) onto the scrub.  

 

When the stock recognize the sound of the saw, you should move away from these area and use trees and stands furthest from water.  That way you can preserve the trees closer to water sources for when its hotter or if animals are weaker and won’t browse as far.

 

Impaction can be a real issue, particularly if there is not enough leaf material in the diet.  Twigs can be an issue.  Feeding molasses in troughs can help reduce this risk.  Its also worth providing a supplement of ground limestone in the molasses mix at 1.5%.  This will help maintain animals intakes of calcium.  

 

Signs such as depressed appetite, no cud chewing or discomfort, often characterize impaction.  You might notice animals groaning or even kicking their bellies.  

 

Providing a protein supplement can also reduce the risk of impaction.  A supplement will help stimulate rumen function and ensure material is digested more effectively.  Suitable choices could be molasses and cottonseed meal (fortified molasses mix) or white cottonseed.  

 

If you are cutting scrub, remember if you don’t cut enough, animals will be forced to eat more twigs and small branches.  This can also increase the risk of impaction.

 

The final important consideration when feeding scrub is access to sufficient water.  Stock must be able to access enough water each day.  Reduced water intake can rapidly increase the risk of impaction, so water sources need to be clean as well as reliable.

 

Finally a couple of tips.  Try to use only one species at a time.  Otherwise stock might waste feed by choosing one species over the other.  In hot weather you might have to feed more frequently than a typical 2-3 day program.  Daily cutting might help avoid leaf loss as scrub dries out in the heat and becomes inaccessible to stock.

 

It is important to consider the way you cut and lop scrub.  For regrowth its essential that you try not to cut too heavily, particularly preserving the trunk and major braches.  Some foliage should be left to help the tree recover, ideally above stock browsing height.  You should also really only lop a tree once a season to allow it to recover, although depending on the length of the drought, this period may be much longer.

 

Your own safety is vital!  Climbing trees and using chainsaws are dangerous undertakings.  When you are hot, tired or stressed the risk of injury is much greater. So consider ways to be safe.  Can you do it early when its cool and you are not tired?  Can you access a cheery picker or other method that means you don’t need to climb trees.  

 

Keep thinking is there a SAFER way!

 

Finally after a few months, stock will lose their appetite for scrub.  So I reckon it is important that your plan takes this into account.  If you don’t know what the next phases might be, then why don’t you get in touch with me and we can work a plan out together.


Comments

Bill Guest commented on 17-Jan-2019 09:18 PM
Have you a feed value for curracabar

Post a Comment

Captcha Image


Latest Tweets