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2.2 Crabs
2.2.1 Introduction
Crabs are decapod crustaceans of the infraorder Brachyura. They have a very short
projecting “tail” (abdomen) usually hidden under the thorax. They live in all oceans,
in fresh water, and on land. They are generally covered with a thick exoskeleton and
have a single pair of pincers. Crabs are decapod crustaceans of the infraorder
Brachyura. They have a very short projecting “tail” (abdomen), usually hidden
under the thorax. They live in all oceans, in fresh water, and on land. They are significantly evaluated economically in some countries of the world. It is consumed
with pleasure due to its high nutritional value and attractive taste and flavour. They
should be consumed quickly after harvest as they change the quality in a very short
time after they die. They are processed by various methods for consumption as well
as maintained by various methods.
Most of the crabs live in sea, freshwater and brackish waters. In addition to their
basic duties in the ecosystem, crabs are consumed as nutrients in many countries.
Generally marine species are consumed as nutrients. They are economically evaluated at a significant level in the countries such as China, France, Indonesia, Japan,
Philippines, Spain, Thailand, and United States. It has also been reported that crab
species in the world has been evaluated as feed additive and fertilizer purposes as
well as direct consumption as food (Gulle et al. 2007).
Crabs are creatures that are cultured besides catching from their natural habitat.
All cultured crabs are marine species. Although crab culture is not commonly done
in Western countries, especially Mithrax spinosissimus (Lamarck, 1818), Scylla serrata (Forskal, 1775) and Portunus pelagicus (Linnaeus, 1758) cultivation is common in East Asian countries and Japan (Lee and Wickins 1992).
2.2.2 General Information About Crabs
2.2.2.1 Biology of Crabs
Crabs are covered with a hard shell called carapace made from chitin. This shell,
which acts as an exoskeleton, is usually lead-coloured. Head and thorax parts are
fused and covered with carapace. Their bodies are in enlarged form. The body of the
crabs is enlarged on the cephalothorax in the Brachyura sub-order of the Decapoda
order. Cephalothorax is seen almost from the top. Carapace is oval shaped. The
abdomen, which consists of seven segments, is small and curled towards the bottom
of the thorax and not seen from the top. This section is tapered towards the end in
males, while in females it is wider and circular. In both male and female sex, the
abdomen is folded over the sternum, starting from the starting area to the ventral
side. In male individuals, narrow and pointed tips, female individuals are more oval,
2 Crustacean Shellfish
2.2 Crabs
2.2.1 Introduction
Crabs are decapod crustaceans of the infraorder Brachyura. They have a very short
projecting “tail” (abdomen) usually hidden under the thorax. They live in all oceans,
in fresh water, and on land. They are generally covered with a thick exoskeleton and
have a single pair of pincers. Crabs are decapod crustaceans of the infraorder
Brachyura. They have a very short projecting “tail” (abdomen), usually hidden
under the thorax. They live in all oceans, in fresh water, and on land. They are significantly evaluated economically in some countries of the world. It is consumed
with pleasure due to its high nutritional value and attractive taste and flavour. They
should be consumed quickly after harvest as they change the quality in a very short
time after they die. They are processed by various methods for consumption as well
as maintained by various methods.
Most of the crabs live in sea, freshwater and brackish waters. In addition to their
basic duties in the ecosystem, crabs are consumed as nutrients in many countries.
Generally marine species are consumed as nutrients. They are economically evaluated at a significant level in the countries such as China, France, Indonesia, Japan,
Philippines, Spain, Thailand, and United States. It has also been reported that crab
species in the world has been evaluated as feed additive and fertilizer purposes as
well as direct consumption as food (Gulle et al. 2007).
Crabs are creatures that are cultured besides catching from their natural habitat.
All cultured crabs are marine species. Although crab culture is not commonly done
in Western countries, especially Mithrax spinosissimus (Lamarck, 1818), Scylla serrata (Forskal, 1775) and Portunus pelagicus (Linnaeus, 1758) cultivation is common in East Asian countries and Japan (Lee and Wickins 1992).
2.2.2 General Information About Crabs
2.2.2.1 Biology of Crabs
Crabs are covered with a hard shell called carapace made from chitin. This shell,
which acts as an exoskeleton, is usually lead-coloured. Head and thorax parts are
fused and covered with carapace. Their bodies are in enlarged form. The body of the
crabs is enlarged on the cephalothorax in the Brachyura sub-order of the Decapoda
order. Cephalothorax is seen almost from the top. Carapace is oval shaped. The
abdomen, which consists of seven segments, is small and curled towards the bottom
of the thorax and not seen from the top. This section is tapered towards the end in
males, while in females it is wider and circular. In both male and female sex, the
abdomen is folded over the sternum, starting from the starting area to the ventral
side. In male individuals, narrow and pointed tips, female individuals are more oval,
2 Crustacean Shellfish