This study intend to assess prawn farms performances in Guatr gulf, Iran via FGLR and FGNZ approaches, total factor productivity changes and its component. The data analyzed by input distance function considering the Malmquist index (MI). In order providing data, total of 25 prawn active farms were interviewed. The results showed the majority of farms face decrease in Total Factor Productivity (TFP). So that, TFP growth discerned only for 36% of farms and 64% of the units had TFP decline which due to decrease both technological changes (TC) and efficiency changes (EC). Pure efficiency change is the main factor to diminution efficiency change and therefore productivity growth. Total productivity depends on improving organizational structure, procedures, policy and decision-making process. Training courses on techniques in prawn culture is offered to improve inputs management in order to increase productivity. Furthermore, farmers should share their experiences in a mutual advantage. Moreover, Creating and managing a reward and punishment system on the farms should be selected. Regarding to scale efficiency change, strategic planning to change farms scales and making some fundamental changes in the production process could be adopted as well. For instance, to ameliorate productivity, it offers to equip farms with aeration systems. However, the most farmers need more financial assistance from government agencies

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