Vet on Call: Why zero grazing offers better returns than semi-zero grazing

Last week’s article on what one needs to do to run a profitable zero grazing unit elicited plenty of responses.

Many farmers were at a crossroads on whether to embrace zero or semi-zero grazing.

Nathan from Uasin Gishu County wrote: “I have read your article and it has good information. I request that you send me the design template for a zero-grazing unit. I intend to start it with 50 cows in Eldoret on a 25-acre farm. Can I do semi-zero grazing?”

I was encouraged by Nathan’s resolve to earn from dairy farming and create jobs. To answer him, he can graze the animals on his 25 acres, which is called open grazing.

However, it is a very inefficient milk production method and animals never attain their potential due to too much energy being wasted walking in search of food and water.

Animals also get inadequate food, which is also deficient in nutritional composition.

He can also do semi-zero grazing, where he confines the cows in an enclosure for part of the day and releases them to pasture for the rest of the day. From Nathan’s question, this appears to be his preferred dairy farming method.

Finally, he can execute his dairy production in a zero-grazing unit where his cows would be confined throughout their lives. But like Nathan, many farmers must be wondering, which is the most economical but productive method.

The fact that one has land for grazing cattle is not sufficient justification for open grazing dairy production. One must consider other factors such as using the land in many different ways, otherwise called multiple land use, to maximise financial benefits from it.

For Nathan, he plans to keep 50 dairy cows that would never thrive on 25 acres of land in open grazing.

GOOD IDEA ON THE FACE

Semi-zero grazing sounds like a good idea on the face of it because Nathan would put the cows in for some time and then release them to pasture. However, this kind of dairy production would not give him the benefits of zero grazing.

On the contrary, it would give him all the disadvantages of open grazing. These disadvantages include inefficient use of land, wastage of pasture due to trampling, low milk production, poor disease control and manure loss among others.

In a study that Egerton University carried out, zero grazing in Kenya yields on average 3,300 litres of milk per cow per year followed by semi-zero grazing at 2,340 litres. Open grazing trails with 1,800 litres per cow per year.

When one looks at these figures keenly, it is obvious that semi-zero grazing is only 30 per cent more productive than open grazing.

Zero grazing is 40 per cent more productive than semi-zero grazing and 83 per cent more productive than open grazing.

I advise Nathan to go into zero grazing for more efficient dairy farming and better land use. The farmer must, nonetheless, be aware that the high efficiency of zero grazing may result to low profits unless he puts measures to control high labour costs and losses associated with poor inputs such as feeds.

This is because according to a study by Tegemeo Institute, labour and quality of inputs can heavily reduce the profitability of zero grazing.

The research findings can be accessed on the link http://www.nation.co.ke/business/seedsofgold/Why-you-should-think-twice-about-zerograzing/2301238-3496502-jahdyo/index.html

Other farmers who called me asked, “Why do cattle in zero grazing produce more milk?” The answer lies in understanding the way two key complex biological factories in the cow’s body operate.

SOPHISTICATED COW STOMACH SYSTEM

First is the sophisticated cow stomach system. It comprises four units being the rumen, reticulum, omasum and abomasum in that order based on their functions.

The rumen is the largest of the stomach units and is the main food processing unit of the cow.

It breaks down food unusable by human beings into the nutrients required by the cow both for body functions and milk production.

Interestingly, the cow is not responsible for the complex digestion; it is done by billions of microorganisms resident in the rumen through a fermentation process.

These microorganisms are bacteria, fungi and protozoa each responsible for digesting different kinds of food materials.

The reticulum serves to help the cow stomach sort out what should be regurgitated for further chewing and what should be passed into the omasum, the book-like stomach unit.

The omasum absorbs water and many other nutrients into the body and passes the rest into the abomasum; the equivalent of our stomach.

Digestion of proteins and carbohydrates occurs in the omasum before the contents are passed into the intestines for further digestion and absorption.

The digestion process of a cow requires a lot of water, saliva and energy to complete. A cow on plant fodder produces about 150 litres of saliva per day; and 40 litres if it is on a high grain and concentrates feed.

This explains why dairy cattle require about 60 litres of water per day.

COMPLEX SCIENCE

The udder is the second factory that we need to appreciate in the cow’s body. It contains milk secreting cells that mix water, proteins, fats, vitamins, minerals and other ingredients to give us milk.

The milk is actually meant for the calf. This process again requires a lot of energy and water. In most cattle breeds, the water content is over 87 per cent.

The total water available to the cow is the one taken in as pure water and the one contained in feeds. Cows on dry feeds therefore require more water than those on juicy forage.

Zero grazing, consequently, helps the cow to have ready access to water and to allocate more energy and nutrients to digestion and milk production.

Further, the feeding with a fairly constant type of feed helps the rumen microorganisms to efficiently digest the food in a predictable manner.

Constant changes of feed confuse the microorganisms or may require changes in the populations of the various microorganisms hence frustrating efficient digestion.

I can thus conclude for Nathan and other dairy farmers that zero grazing is a dairy production method based not only on the need for better land use but also the complex science of cattle digestion and milk production.

For maximum benefits in your zero grazing, avoid frequent or sudden changes in feeds and provide sufficient water for cows to drink at will.