This invention relates to a method of preparation for preservation of hay and other dried forages for animals, 5 especially ruminants and horses. The invention furthermore relates to agents to accomplish the preparation.

The treatment of pasture feed to hay of high quality causes often problems: 10

- Harvesting may be problematic because of rain and humid weather.

- It may be difficult to dry the hay because of rain and humid weather .

15 - Badly harvested and badly dried hay is difficult to store.

- Badly stored hay is from many aspects condemnable for the animals, who are supposed to eat it, because .harmful fungi deteriorate the nutritional value, further they may be directly noxious for the animals .

20

It is thus of outmost importance to obtain a properly stored hay. The risk for storage damages increases by harvesting using modern technology, e.g. big bales. Such bales are com¬ pact and difficult to dry afterwards. Earlier, hay was dried

25 preponderatingly on hay rack. Normally a dry matter (DM) content of 85 % was obtained. Hay does inevitably carry a field flora as well as a storage flora of mould spores. To prevent these to develop sodium chloride (common salt) 10-15 kg per ton dry hay was added by hand when loading in

30 the loft or in the barn. Furthermore the salt improved the palatability. The storage moulds are growing at lower water content than the field moulds. The storage moulds are

'-? copiously spore forming. The risk, that the mould ^' spores shall develop, increases with increased moisture content in

35 the hay.

Todays technique, where the hay is dried in strings on the

ground including a couple of turnings and the string is picked up and pressed to bales or big bales, has heavily increased the risk for mould damages of the hay. The farmer is to a considerably higher degree than before in the hands of the powers of the weather and is in diffi¬ culty obtaining the same high dry matter content as by rack drying and by loft drying. Addition of salt in connection with string pick-up is inefficient because of inho ogenious distribution in the hay. Practical experi- ence has shown, that even if a smaller part is untreated and mould formation has occured there, the whole lot must be rejected. Mold formation causes a serie ^* s of problems:

- The nutritional value and energy content is deteriorated. - Mould spores in great amounts irritate the respiratory pathways of the animals as well as of the cattlemen and may cause e.g. pneumonia.

- Moulds affects the conditions in the digestion path of the animals. - Mould toxins may cause e.g. chronic kidney damages, abortion and deteriorated feed conversion.

- Mould toxins are transferred into the milk and causes problems in dairying. Such milk must in principle be rejected.

Mould formation thus causes environmental problems for the cattlemen and influences on the health of the animals as well as on the milk. In addition there are the economic consequences. If conditions for mould formation are on hand, degradation of organic matter takes place under heat formation and formation of carbon dioxide and water, which accelerates the mould formation. One says, that the hay is "breathing". Most obvious this is in big bales.

For the reasons above and common experience so far the _* farmers are advised not to use chemical preservatives for hay. It is considered, that ho ogenious addition and there-

fore acceptable results are from a practical point of view impossible to reach. See e,g. the brochure "Something about mould poisons" issued by the Swedish Association of Dairies, 1986.

It has, however, surprisingly been shown possible to effect an efficient preservation without the serious problems stated above. With this aim the invention shows a proce¬ dure characterized by the features, which appear from the belonging claims 1 - 3, as well as an agent characterized by the features, which appears from the belonging claims 4 - 8.

The invention idea is to prevent any form of fermentative and other biological activity unlike the silage process, wherein newly harvested forages in undried form are treated in order to obstruct any butyric and acetic formation by fermentation and to create favourable conditions for lactic acid formation.

By treatment according to the invention the forage thus is supplied an agent with the ability to give a high osmotic pressure in the moisture of the forage. The agent is supplied in finely dispersed form (atomized) in an amount sufficient to blockade the growth of the harmful fungi. The forage so treated is then taken to storage. The agent is suitably supplied in the field in connection with picking up from the ground or transport to storage, preferably by spraying through a nozzle.

The agent according to the invention for accomplishing the treatment according to the invention is essentially a con¬ centrated water solution of an electrolyte possessing high water solubility, stable at actual working temperature, which does not contain for animals or humans harmful elements .

Preferably the electrolyte is a chloride of alkaline-earth metals, especially calcium and/or magnesium chlorides are preferred.

To improve the stability of the solution at working tempe¬ rature up to 10 . propylene glycol, glycerol or other addition for decreasing the crystallization temperature may be added to the water solution. This is of importance as concentrated electrolyte solutions are persued, but preci- pitation e.g. by crystallization must be avoided, as this would block the spraying equipment and make further application impossible.

The invention will now be described more in detail, partly as example of application and with reference to the attached figure, a diagram showing the osmotic coefficient as a function of the concentration of electrolytes. All percentages here and before are weight by weight. If in connection with the picking up a uniform distribution of electrolyte in suitable quantity is effected in the hay, the so obtained osmotic pressure prevents the flora of mould spores to develop and prevents furthermore any fer¬ mentation processes to occur. A uniform distribution is according to the invention effected by spraying a concen- trated solution of a suitable electrolyte in finely dis¬ persed form. Such a solution does not segregate, but adheres to the hay because of its* stickiness, which in¬ creases with increased concentration of the electrolyte solution. In addition further penetration and distribution occurs by diffusion. Such an electrolyte must fulfill a series of demands:

- Must not be composed of material toxic or harmful for the animals - Must not contain injurious content of certain impurities, e.g. heavy m t ls

- Concentrated solutions shall be possible to achieve with¬ out risk for crystallization or precipitation at tempe¬ ratures actual at field conditions.

- Shall give a high osmotic pressure.

For a series of in et per se possible electrolytes the relationship between concentration and osmotic coefficient is given in the attachaed figure. It shows, that the pre¬ ferred electrolytes magnesium chloride and calcium chloride markedly differs from the other electrolytes. The explana¬ tion behind this is, that magnesium chloride and calcium chloride in water solution are surrounded by a shell of a great number of attached water molecules (high hydration number) thereby decreasing the amount of free mobile water molecules. The other indicated electrolytes have a low hydration number and therefore possess low osmotic coeffi¬ cients. Furthermore magnesium, calcium and chloride are essential mineral components for the animals.

Exemple

On a windrow field dried hay to 75 % dry matter content, which was pressed to bales, no treatment and treatment in connection with the pressing by spraying 20 litres per ton hay of a solution containing 17.1 % MgCl2 and 23.3 _ CaCl2 were compared.

Evaluation was made after.-3 months storage.

treated untreated visual inspection no mould extensive mould formation formation

ratio non diαestable protein 0.068 0.116 total protein