March 22, 2009

Angora (Mohair) Goat Basics: Feeds available for goats

Agriculture, animal husbandry, goats, Mohair, Angora, feeds, feeding, nutrition

By Dr Clive Dalton


Feeds available to goats


Pasture
  • Future goat farming in New Zealand is based on pasture feeding, and as world grain prices have gone crazy less of it will be fed, and it will be fed more carefully.
  • The problem with “pasture“ as a feed is that it varies in quality and quantity every day of the year. It goes from low DM, low fibre, high protein and high digestibility in spring and autumn, to low protein, high DM, high fibre and low digestibility in the summer.
  • Balancing all this to meet the nutritional needs of the stock at different times of the year is often described as more art than science.
  • The other key to good pasture management is the balance between roots and shoots. The shoots generate nutrients through photosynthesis so are the factory of the plant. If you keep them grazed off hard, then it takes longer for them to recover and made food to be stored in the roots.
  • This is why rotational grazing is successful as it allows time for shoots to recover before being grazed again.
  • The aim of all plants is to mature quickly and go to seed so the key to grazing management is all about “controlled defoliation” to prevent them doing this.
  • Remember of course that with goats, they will prefer the seed heads over lush green leaves and clover.
  • It’s not economic in New Zealand to use machinery and diesel to control pasture, so the animal is used instead. So the animals control the pasture and the pasture feeds the animals.
  • Again it’s a question of keeping a balance and making decisions well ahead of time e.g. When stock should be moved and when pastures will start going to seed.
  • When you can see 10-15% of seed heads in a pasture, it’s time to make silage and this will be good quality. If the seed heads have gone beyond this – then it’s a hay crop.

Supplementary feeds

Hay
Good things about hay
  • Cattle of all ages will eat hay with relish unless it’s really old, mouldy or full of thistles or docks.
  • Hay has high DM (86%) and the high fibre content is good for rumen digestion which generates heat in the animal.
  • It’s easy to make hay as long as the sun shines.
  • It’s easy to handle when baled in the paddock, in storage and when feeding out – provided you have small bales or equipment to handle big bales which seem to get bigger every year.
  • Hay keeps well for a couple of years and is easy to buy and sell.
Bad things about hay
  • It can vary greatly in quality depending on the pasture it was made from and how mature the crop was when it was cut, also how badly it was weathered before baling.
  • You lose about 80% of the feeding value of the original grass crop when you make hay of it.
  • The protein content in good hay is only around 4%.
  • Hay will catch fire, and if baled or put in a shed slightly damp it will heat up and self-combust.
Pasture Silage Good things about silage
  • In good silage you only lose about 20% of the original nutrients from the pasture if cut at the 10-15% seed head stage.
  • Good leafy silage is a high protein feed at around 17-20% protein in the DM.
  • Really good silage is around 25% Dry Matter.
  • After cutting a silage crop the paddock will return to regrow quicker than with hay.
Bad things about silage
  • Silage smells and many people say it stinks, regardless of whether it was made well or badly. On small farms this regularly causes problems with non-rural neighbours.
  • You must get everything right in the ensiling process or you’ll end up with an inferior product which can cause animal and human health problems - especially if it goes mouldy.
  • You cannot make good silage from short, lush spring pasture as it is hard to get a good fermentation, and the end product will be only 20% DM or less. This will restrict the nutrient intake of the stock.
  • Likewise, pasture that is well on the way to hay makes poor silage.
  • Silage is hard to cart around and feed out as bales are 500-700 kg, and too many folk have been injured by them. A bale on a small trailer pulled by an ATV can jack-knife and kill you.
  • If you open a bale in the paddock and let stock help themselves, the acid in the silage will burn the grass and the stock will pug the area. Burning can also happen if you dump it in great forkfuls and stock don’t clean it up that day.
  • The juice that can leak out of bales or pits is an extremely bad environmental hazard as if it gets into streams it eats up large quantities of oxygen.
  • Old silage wrap is an environmental hazard too. It can cause serious digestive problems in stock if they eat it and it blocks open drains. It is supposed to be disposed of in “an approved land fill” – which could cost you dollars.
  • Wrapped bales need care in handling and protection from stock, rats and magpies to prevent punctures, air entry and mould.

Balage and haylage
  • There is no difference between these supplements and balage seems to be most commonly used! Both are made from a very mature crop that ends up around 40% DM.
  • But beware especially when buying it as it could be a hay crop that became wet, or a silage crop that went too far to seed.
  • Get a sample analysed to be sure what’s in it before you buy it. And pick the sample from a range of bales.
A buyer’s guide to silage
  • When you buy silage, get the vendor to open a bale and dig deep inside to see what it’s like.
  • Check the bales for tiny holes as mould forms quickly if air leaks in. You can also do a squeeze test. Take a handful and squeeze it hard and if juice comes out between your clinched fingers – it’s too wet and certainly below 20% Dry Matter.
  • Or take a sample and twist it to see if juice appears. It’s easy to squeeze juice from wet silage lower than 20% DM. Do a “sniff and feel” test using Table 16.

Silage quality check list

Send a good representative sample of the silage to a laboratory for feed analysis to get DM%, Protein% and ME.

Other crops
Look in any seed company’s catalogue and you’ll see a wide range of crops that can be grown to feed goats. The term “crop” covers such things as subtropical grasses and a wide range of brassicas and pulses. The catalogue information is comprehensive and well presented and companies have specialist agronomists who will help you. The key things to look out for are:

  • When do you need the extra feed the crop will provide?
  • What yield of Dry Matter can you expect per hectare?
  • What climate limitations does the crop have? Will it grow in your area?
  • What soil type limitations does it have?
  • What fertiliser requirements does the crop have?
  • How will you control weeds? These are always a major threat.
  • How will you harvest the crop – do you need a machine or can it be grazed?
  • Are there any animal health risks from grazing the crop?
  • What are the costs of establishment?
  • How long will the pasture be out of production while the crop is growing?
  • How do you treat the paddock after the crop?
  • There are probably many more questions so that’s why you need to talk to an agronomist.

Maize silage
  • Maize silage is high in carbohydrates and low in protein.
  • It’s a good winter feed when animals are dry or during spring to supplement lush green pasture.
  • It’s a bulky feed so make sure milking does are fed any high-energy grain feed first.
  • Maize silage needs to be kept well covered at the pit face as moulds grow very quickly.
Concentrates
  • These feeds are based on grains (barley and maize) and hence are very expensive per kg of DM. A kg of DM in spring pasture may cost 10cents, in silage 20c, and 80-90c in commercial meals. So they need to be confined to times of clearly defined need.
  • The are “supplements” and not “substitutes“ for their pasture diet, as this will eat up any profits in the enterprise.
  • The full nutritional content of the meal must be shown on the bag.
  • Goats soon learn to eat meal but start at 40-50gm/head/day for 7-10 days, and don’t exceed 0.200g/head/day for adults. Dams will soon teach their kids to relish grain-based feeds.
  • For lactating goats, check their mineral needs. Some farmers add 1% of ground limestone or cement if feeding for longer than two months. Check this with your veterinarian.
  • Coccidiostats can be added to grain feeds but discuss this need with your veterinarian.

Weeds
  • Goats are not miracle workers able to produce quality mohair fibre from scrub and weeds. Good fibre comes from good nutrient intake.
  • Feral but also Angoras have been used for weed and scrub control, and there have been some spectacular results. In trials, as well as pasture weeds, they dealt successfully with gorse, sweet briar, manuka, kanuka and tutu.
  • When new shoots on weeds and shrubs are growing rapidly, they are high in protein and energy and will meet the full nutritional needs of mohair goats, but in winter when bark is eaten because there is nothing else, nutritional needs will not be met.
  • Ringbarking is certainly an effective way to kill woody weeds and may be a planned management practices.
  • Stocking rates to achieve these results need to be around six goats/ha.
  • However, it would not be good practice to use Angora goats farmed to produce high quality fibre to break down scrub although they’d be well able to deal with pasture weeds.
  • If you want to leave selected trees in areas where goats are eating scrub, then they need to be protected from bark damage as the goats do not discriminate.
Feeding levels
  • It’s important to remember that the fibre processor wants a fibre that is even along its length, and feeding levels control this. Synthetic fibres don’t have this problem and that’s why they have been such a success.
  • There is a genetic limit to how thick the fibre will grow but the environment (feeding) can certainly dictate how thin it can grow and in times of starvation the fibre will be so thin that it will break. In Merino sheep this is called “hunger fine”.
  • Little work has been done on the precise feeding levels for pasture fed Angora goats in New Zealand, and even if we did know these, it would be difficult to work out how to provide them because of the way goats graze and browse.
  • Feeding an even pasture sward of 2300kg DM/ha, rotationally grazed on a 40day rotation would be easy to work out what they were getting, but this is not the way goats are fed.
  • A good New Zealand pasture made up of 70% grass and 30% clover will provide feed that has protein and energy levels, as well as minerals and trace elements for most of the year to meet the needs of mohair goats.
Target liveweights
A “target” weight is not an average weight. It’s a minimum weight and should be reached or exceeded by all animals in the group.



Nutrient values of feeds
This table shows the Dry Matter (DM%), the Energy Value measured in Metabolisable Energy (ME) and Crude Protein (CP%).

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