Safeguarding the welfare of farmed fish at harvest

Abstract

Fish welfare at harvest is easily compromised by poor choice of handling and slaughter methods, lack of attention to detail and by unnecessary adherence to fish farming traditions. The harvest process comprises fasting the fish to empty the gut, crowding the fish, gathering and moving the fish using brails, fish pumps, and sometimes also road or boat transport and finally stunning and killing the fish. The harvesting processes commonly used for bass, bream, carp, catfish, cod, eel, halibut, pangasius, salmon, tilapia, trout, tuna and turbot are outlined. These harvesting processes are discussed; the consequences for fish welfare identified and practical tests which can be made at the harvest site highlighted. Welfare at harvest for the majority of farmed fish species can be improved by adopting and adapting existing procedures already known to be beneficial for fish welfare through their use in other fish farming systems or with other species. It is seldom necessary to develop completely new concepts or methods.

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Correspondence to J. A. Lines.

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Lines, J.A., Spence, J. Safeguarding the welfare of farmed fish at harvest. Fish Physiol Biochem 38, 153–162 (2012). https://doi.org/10.1007/s10695-011-9561-5

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Keywords

  • Fish
  • Welfare
  • Slaughter
  • Stunning
  • Harvest
  • Transport