Search the site:  
Chapin Livestock Supplements Dairy Nutrition  

Home Page
Roy Chapin's CV
Swine Nutrition
Dairy Nutrition
Human Issues
Agrobusiness Administration

Answer to your question on forage quality, cutting and preservation

Hi David!

You asked about my impression of Ukrainian farmers' knowledge of how to and ability to produce good hay and silage

I don't think the typical Ukrainian dairy or beef feeder understands the importance of cutting forage at the proper time at all and in general they do a lousy job of timing the harvest and in storing the forage. It is the one most significant change that they could make to improve animal performance of ruminants in Ukraine and it wouldn't cost much. LOL could do a big service by having forage experts give seminars and visit the farms.

Those big piles of hay that are out in the weather, turning brown or black, that you see workers loading on to wagons to feed their cattle this time of year are not much better than straw in feeding value. Besides the poor storage conditions, the forage was probably not cut at the proper time - or it may even be crop residue from the harvesting of grains - straw - to begin with. At any rate, I haven't seen good forage at any place or at any time during my three years in Russia and Ukraine. That doesn't mean that it doesn't exist but good forage management is certainly not widely practiced.

Forages have an optimum time when they should be harvested. This is pre-bloom in alfalfa when no more than 10 percent or less of the field is in bloom at the time of cutting. With grasses it is before they begin to head out while the stock is still milky. It can differ per variety. When you let forage over-mature the animal will eat less of it so their intake of dry matter goes down. In addition, what they do eat is lower in protein and energy. To further add to the problem, the digestibility goes down. Therefore, animal production is compromised if the forage being fed is past maturity at harvest because the animal will (1) eat less dry matter of a forage that (2) contains a lower level of nutrients (3) that are not as well digested. That's a triple whammy when forages are harvested late.

With high producing dairy cows, dry matter intake is often the limiting factor. One reason California has such high levels of milk production is because they have access to some of the best alfalfa hay in the world. You can't get maximum milk production without quality forage. During my life time I have seen the superior forage making knowledge demanded by California dairymen move to the Pacific Northwest (Oregon, Washington and Idaho) and transform forage making procedures in the PNW into a high tech process that now supports some of the best dairy production in the world. It can be learned and Ukraine is ripe for this knowledge and application of quality forage making.

With corn silage the problem is a little different. As the corn matures there is a slight decrease in the feeding value of the stalk while there is an increase in the energy value of the corn grain that is maturing. It is generally accepted that corn silage should be cut when the grain is in the milk stage with the black line about half way down the corn kernel. If possible, corn silage should be cut before a lengthy frost dries out the stalk.

Ukrainians could do a lot better job of feeding their cattle if they harvested their forages at the right time. The date of when the forage should be harvested will vary with the climate and crop species. One of the big functions of U.S. Ag Extension people is to help the forage raiser decide the optimum harvest time of the forage. Raising and cutting forage on time in experiments in Russia have shown great and amazing improvements in milk production.

The objective is not to harvest the maximum tonnage of forage from a field but to cut it at a time that will allow the maximum production of milk from a hectare of forage. There is often a lot of conflict between the agronomist who is rewarded on tons harvested and the zoo-tech who is rewarded on milk produced. They don't have the same objectives. The farm director doesn't always know the difference, based on my personal conversations with farm directors. Working in Chile I was pleased to see the forage raising objective being the tons of milk produced per hectare rather than the tons of forage produced.

After harvest, hay should be stored in a dry place away from the sun. With storage the vitamin A level will decrease. In Ukraine, forage is all too often stored, uncovered, in the field and is thus open to the elements of rain, snow and sun. Much feeding value of forage is lost due to poor storage. This can be corrected and should be.

It is best if silage is made in upright silos. These are not very cost-effective and are not usually available in Ukraine so it is logical to use silage pits. These can be dug into a hill-side where the water table will not rise above the floor level and flow into the silage.

Corn silage plants should be cut at about 30 percent dry matter. Drier corn fodder will be hard to pack to expel oxygen. If the silage corn is harvested with a higher moisture level, there is too much liquid run-off that carries nutrients with it. The amount of favorable types of acids produced in the ensiling process can be compromised as well if the silage is too wet. I saw some corn silage being made in Rivne, Ukraine where the corn plant had been frozen and was too dry. It was hard to pack the silage with a lot of mold and heat coming from the pile as it was ensiling - particularly around the open surfaces. When I asked the farmer about it he wasn't interested in my comments and said it was being done just right. Not wanting to listen and learn is a real killer of progress and improvement. Ukraine needs some adult learners for farmers.

When the silo is filled the forage crop needs to be packed to remove as much oxygen as possible as ensiling is an anaerobic (without oxygen) process. Ideally, the forage should be crushed to remove the air but not chopped too fine as that will reduce rumen function when it is fed. The percentage of butterfat is lower from cows fed finely chopped silage and there is more of a chance of rumen dysfunction. When the stalks are crushed flat during the cutting process, the forage is easier to pack in the silo. There are special machines to do this that are not usually available in Ukraine. Usual methods of packing include driving a tractor - preferable a crawler tractor - over the silage until the air has been expelled. This can be a dangerous occupation as the tractor can roll over side to side or end to end.

Since silage making is an anaerobic process, if oxygen is present you don't get good ensiling. You want the anaerobic processes of ensiling to allow a rapid increase in the level of acids so as to pickle the silage, killing the micro-organisms that are digesting the forage and producing acid that are necessary to preserve the silage. If too much air remains in the ensiling material, it takes too long for the ensiling process to be completed, using up too much energy from the forage and thus reducing its feeding value. With air trapped in the silage you will get heating and spoilage. You can also get the production of less than desirable kinds of acids as well as mold and yeast growth. Alfalfa is harder to ensile than grass and grass is harder to ensile than corn silage. Alfalfa contains abundant calcium that neutralizes the acids and allows the fermentation process to continue longer. Corn silage is higher in starch than alfalfa or grass and thus rapid fermentation is facilitated.

The silo should be covered with plastic held down by tires or soil or logs or something to protect the upper level of the silage and to reduce the damage from water and melting snow. This covering should be removed gradually as the silage is removed and fed. Expect some spoilage on the exposed surfaces that should be discarded before feeding as spoiled silage can cause rumen fermentation problems. The management of making silage and of feeding it is a science.

The width of the silo should be narrow enough so that when you cut into the silage to feed the animals, an open face is not left for more than a day or so. The hotter the climate, the less time before silage deterioration will occur. If the pit is too wide or too tall (has too wide an open face), by the time the silage face is cut again it will begin to mold. If the silage feels warm and is smoking, then microbial activity is taking place and nutrients - energy and protein - are being wasted.

Silage can be made on a flat surface but that increases the exposed surfaces and increases nutrient loss. Ukrainian farmers should build pit silos either by digging into a mountain side, piling up soil around three sides of it or building ends and sides with wood or concrete. Ground water must be excluded and the top protected from rain and snow. Oxygen must be excluded by packing.

The art of making silage can be taught and if learned and applied would greatly increase the feeding value of the forage being ensiled. There is way too much loss of nutrients from improper forage harvesting and storing in Ukraine. Great economic progress can be made if forage producers are trained properly in the science of ensiling and use their training. This wouldn't cost them a lot more than their present techniques. You can't adequately make up for poor forage by feeding more concentrate (grain, protein and vitamins and mineral) so the place to start to improve ruminant rations is to grow, harvest and store forage under optimum conditions. This is a place where animal agriculture can be made more profitable by working smart and this isn't very expensive to do. This is the place that the feeders of ruminant animals should start if they want to make big improvements.

[David, you asked for an answer in a sentence or two. I couldn't even keep it to a page or two.]

© Roy Chapin, 2024
  Home  Search the site  CV  Works Top