Firstly, thus, the nutritional requirements of cows for their own development and health should be identified. The following elements should be borne in mind:

Energy (kJ)
Proteins (g)
Lipids (g)
Carbohydrates (g)
Minerals (mg)
Vitamins (mg)
Water (l)

The aim of agroecological livestock farming in the context of food sovereignty, is to jointly satisfy these needs as well as possible with those resources available on a given farm. As such, grazing and/or harvesting the forage from fields on a given farm is vital. Once the nutritional elements these fields can supply are identified, (a) the need to introduce other forage species (not local but capable of adapting to local conditions) can be assessed, as can (b) the need to supplement dairy cow fodder with raw materials imported to the farm and which of these would be the most appropriate bearing in mind all the above-mentioned objectives in terms of agroecology in the context of food sovereignty and (c) a comparison can be made between dairy cattle feeding regimes based mainly on local forage and those feeding regimes that depend on intensive use of imported feed or concentrates.

With regards to the information offered below, it should be borne in mind that the concentration of the different nutrients found in fodder (feed and forage) depends on the interaction of various factors, particularly: the type of bedrock and soil, each species of plant, the stage of maturity of a plant, meadow and pastureland management, fertiliser application, weather conditions, season and the distribution of mineral elements within a plant: Thus, for example, the concentration of proteins, energy, calcium, phosphorus, and digestible dry matter fall as a plant matures, whilst the concentration of fibre increases. For these reasons the values quoted throughout the present document are average values, unless otherwise indicated.

In the specific case of the Vista Alegre farm, the dairy cows graze the farm’s  pastures all those months that the weather permits (March/April to November) and fresh green grass and a hay and silage crops are also taken from some of the same fields for the animals’ winter feed. The soil structure of many fields (but not all) has been actively altered to a greater or lesser degree over the years, mainly because they have been sown periodically with perennial rye-grass (Lolium perenne) and white clover (Trifolium repens). In this sense the fields on the Vista Alegre farm do not differ greatly from the fields on many other farms in the Basque Country: grasses and leguminous species (the pea family) dominate, the two families of plants that jointly provide cows with all classes of nutrients in an optimum fashion.

White clover

Perennial rye-grass

However, most fields on the Vista Alegre farm have not been resown for over two decades, with a few exceptions such a field that was partially resown in 2010. (It is worth pointing out that it is over 50 or 60 years since some fields were mechanically resown). Given that most fields are not resown on a yearly basis, pastures have evolved since over the years and over 125 different species now populate the fields on the Vista Alegre farm. These mainly belong to the grass (Gramineae) and pea (Leguminosae) families, but there are also members of other families such as the Compositae (daisy), Ranunculaceae (buttercup), Scrophulariacaea (figwort) and Labiatae (mint), amongst many others (see below, section 4). This is not only important due to the different quantities of different nutrients that each species contains (and thus a higher or lower forage value), but also due to the fact that different species play different roles of equal importance to feeding per se for the agroecological approach to feeding dairy cows: for example, helping to resist trampling by livestock and thus contributing to soil conservation; increasing natural  biodiversity and thus helping to maintain soil fauna and the balance of the food chain; producing interesting quantities of pollen and nectar and thus encouraging pollination by attracting bees, flies, etc.

It is worth insisting, however, that the nutritive characteristics of many of the plants present in grazing lands are still unknown and only limited data can thus be offered about them.

The usefulness of plants for animal nutrition can be analysed in different ways: One method, used in the present document, identifies each element separately (protein content, vitamin content...), whilst a second method is based on feeding programmes that centre analyses on both basic data and other more complex parameters: % dry matter, (%DM), metabolic energy (ME – Mcal/KgDM), % crude protein (%CP), % rumen degradable protein (%RDP), % neutral detergent fibre (%NDF), etc). Obviously, not all the elements of a nutritional value present in a plant are available to, accessible or of possible use by cows and, again, some are lost during feeding and digestion. Thus, this second method of analysis identifies that nutritional value of plants that cows can make use of. An example of this methodology can be found at the end of section 2.

Below dairy cattle requirements of each class of nutrients are analysed in order to assess, later in the present document, to what extent they are satisfied by the fodder supplied by the fields run by the Vista Alegre farm.

Index