The interest in creating a base-line for development patterns of clusters and clusters' specific characteristics in rural areas is particularly imposed by certain problems, which manifest themselves in similar degrees and provide a generic pattern in different regions and countries, e.g. depopulation and land abandonment, unemployment level and insufficient access to basic services and infrastructure. Certain development patterns and priorities are identified in the regional development in the old EU-members, while the member states from the Eastern parts are still partially restricted by their economic situation and political instability. This puts forth the concept of the 'integration maturity', which refers to the preparedness of each country and its capability to fully exploit the benefits and the advantages of the integration form (Palánkai, 2003), and is still applicable in terms of the economic convergence level of the new-member states in comparison to the EU-15. This statement is especially relevant to the rural business and development that often remains distant and isolated from capital and sources of information and support. With the consequences of the economic crisis and the ongoing economic instability economists, business experts and social scientists have refined a broad range of techniques for making sense of regional economies and analyzing the public policy implications of their workings. Clusters are therefore often perceived not only as patterns for economic transactions and economic outcomes, but also as social systems and multidisciplinary environmental drivers for change.

The main priorities in the contemporary breeding of different animal species have been directed toward the use of intelligent approaches for accelerating genetic progress, ensuring animal welfare and environmental protection by reducing the release of manure and gas emissions

On the basis of a literature review, the directions for transition of agriculture from the productive to the post-productive model are presented. A methodological framework has been developed, including the directions of the transition and the indicators on which it can be assessed. On the basis of this implementation, the passage from quantity to production quality, to the sustainability of agriculture, to new business models based on multifunctionality are assessed. It turns out that the changes in Bulgarian agriculture cannot be assessed unambiguously. The transition to sustainability is accompanied by continued mechanization and digitization of technological processes. There is a simultaneous development of both the productive and the post-productive model of agriculture. Together with the increasing interest in organic production, the implementation of environmentally friendly practices and the implementation of ecosystem services, modernization based on computerization and chemisation continues. The results are part of scientific project DN 15/8 2017 Sustainable multifunctional rural areas: reconsidering agricultural models and systems with increased demands and limited resources funded by the Bulgarian research fund.

One general characteristic of Eastern European countries (EEC) countries is that at the early stage of transition from a central-planned to a market economy the majority of land was returned to the rural population, which resulted in large numbers of relatively small and dispersed land plots. Geographical proximity and the similar institutional model of these countries identify common development constraints: generally small farm sizes, unclear cooperative legislation or inappropriate taxation policies, individualism and general unwillingness by the farmers to collaborate, absence of value chain activities and entrepreneurial spirit. This paper is purposed towards identifying, analyzing and evaluating the causes of economic and social changes in the development of agricultural cooperatives in Bulgaria in the past two decades.