For economists agricultural productivity is often assessed by measuring the production of an agricultural good (e.g. the yield of a food crop) and by estimating its value on the market thus knowing the potential for profits.
However, for many farmers (and in particular, in non-industrial countries) agricultural productivity may mean much more than that. A productive farm is one that provides most of the resources necessary for the farmers family to live, such as food, cloth, fuel, healing plants...It is a farm which ensure food security as well as a way to sustain the well-being of a community. This implies a productive farm is also one which is able to ensure proper management of natural resources, such as biodiversity, soil, water...
For most farmers, a productive farm would also produce more goods than required for the community in order to allow trade.
Diversity in agricultural production system is the key of productivity, as it unable risk management, and preserve potentials for adaptation and change.
Monoculture is an example of such a non diverse production system; In a monocultural system a farmer may produce only crops, but no livestock, or only livestock and no crop.
Livestock raising benefits are that it provides food, wool, hides, transportation. It also has an important value in term of social relationships (gifts in weddings...). In case of famine when crops are not sufficient to ensure food safety and livestock raising, livestock can be used as food. Livestock may also provide manure, which can be used to fertilize cultivated soils, hence help increase the soil productivity.
On the other hand, in an agricultural system bases on livestock raising only, food has to be bought to other farmers, and wastes produced can not be easily disposed of.
Production has many functions, and diversity is the foundation of such production. To ignore the complex functions provided by a farm is thought by many to turn agricultural production into a commodity.