Gammarinema scyllae sp. n. and Monhystrium mangrovi sp. n. (Nematoda: Monhysteridae) from land crabs from New Caledonia

Two new species of nematodes associated with crabs are described from New Caledonia. Gammarinema scyllaesp. n. from the gill chambers of Scylla serrata (Forsskål) is characterised by 3–4 mm long body, small outer labial and cephalic sensilla, distinct ocelli, short straight spicules and sub-cylindrical tail. Monhystrium mangrovisp. n. from the gill chambers and body cavity of mangrove crab Neosarmatium sp. is characterised by 1–1.4 mm long body; outer labial sensilla longer than cephalic sensilla, amphid located at level with posterior stoma chamber, denticles in posterior stoma chamber and five pairs of genital papilla on tail. Phylogenetic relationships of two new species and other nematodes from the family Monhysteridae are analysed based on 18S and partial 28S rDNA sequences.

IMPACT OF COVID-19 ON THE MICROBIAL LOAD OF MUD CRAB, SCYLLA SERRATA: A STUDY FROM SOUTH 24 PARGANAS DISTRICT OF WEST BENGAL, INDIA

This study was conducted to evaluate the microbial load in the flesh and gills of the mud crab (Scylla serrata) collected from the Nagendra Bazar area in Diamond Harbour in South 24 Parganas district of West Bengal, India. The period of collection coincided with the Pre-COVID-19 phase (June 2018 and June 2019) and the COVID lockdown phase (June 2020 and June 2021). It is observed that the total coliform loads in both muscle and gills are more in the pre-COVID phase compared to the COVID lockdown phase. ANOVA analysis also confirmed significant variations between years and body parts (muscle and gills) for both Total coliform (TC) and Fecal Coliform (FC) (p < 0.01). The present study is of considerable importance as crabs are consumed by local people as well as exported in several foreign countries like China, Singapore, Japan, and the U.S.A.

Consumer Preferences and Willingness to Pay for Mud Crabs in Southeast Asian Countries: A Discrete Choice Experiment

The mud crab (Scylla Serrata) is an economically important species found in the mangroves and estuaries of tropical countries and is a popular seafood product in the coastal areas of Southeast Asian markets. The aim of this study is to identify factors affecting consumer preference of mud crabs, and to understand consumers’ willingness to pay (WTP) for these factors in a Singapore market where imported mud crabs from other Asian countries are sold. The results showed that the country of origin matters to participants, affecting purchasing decisions, and consumers were willing to pay approximately 16.48 SGD (11.49 USD, the average price of four shops: 35.55 USD/kg for one mud crab) more if the mud crabs were from Sri Lanka if compared with Indonesian or Cambodian mud crabs. Moreover, consumers were willing to pay 25.08 SGD (17.48 USD) more if the mud crabs were alive and 13.40 SGD (9.34 USD) less if the mud crabs were frozen compared with fresh, but not alive, mud crabs. Furthermore, consumers’ preference in mud crab was associated with the consumers’ religion. Some groups of consumers preferred female mud crabs with eggs over male mud crabs, while other groups preferred male crabs. The results identified diverse consumer preference of mud crabs and, therefore, could provide new insights that are useful for sustainable consumption of mud crabs in the region.

Mud Crab (Scylla Serrata) Value Addition Analysis of Different Actors in Bangladesh

The mud crab business is being considered by most marketing operators to be a profitable and sustainable business due to the high demand in the international market. This study aims to determine value addition at different actors-based steps; primary data was collected from 100 respondents (40 collectors, 10 fatteners, 20 depot owners, 20 suppliers and 10 exporters) who were selected randomly from Khulna, Satkhira and Dhaka district. The mud crab analysis reveals that the value addition of the fatteners was the highest among all other intermediaries which was Tk. 11525 and Tk. 10665 per 100 kg of crab for the grade XXLPD in Khulna and Satkhira district respectively, whereas the lowest value addition was Tk. 1450 and Tk. 1090 per 100 kg of crab for grade KS3. The mentioned districts’ highest value addition by depot owners were Tk. 1191 and Tk. 1200 per 100 kg of crab for the grade FF1 respectively, while lowest value addition was Tk. 691 and Tk.750 per 100 kg of crab for the grade L and M, and by suppliers it was Tk. 2918 and 2758 per 100 kg of crab for the grade FF1. The range of value addition by exporters for Hong-Kong and Taiwan market was Tk. 260.25 to Tk. 13825 per 100 kg of crab. Value addition for exporting female crab to Taiwan market was greater than Hong-Kong market.

The Use of Different Deacetylation Temperature Toward Quality of Chitosan Mud Crab Shell (Scylla serrata)

This research aims to determine the chemical composition (proximate) of chitosan and chitin, The best deacetylation temperature for obtaining chitosan, and the yield of chitosan and chitin from mud crab. This research was conducted in two stages, that is: 1) Preparation of mud crab flour and 2) Extraction and analysis of chitin and chitosan. The experimental design used for chitosan isolation was Completely Randomized Design (CRD). The process of deacetylation chitin becomes chitosan by using 50% NaOH with varying heating temperatures (120, 130, and 140°C). Parameters observed were yield, moisture content, ash content, and degrees of deacetylation. The result showed that the best chitosan was obtained by chitin deacetylation process into chitosan using a temperature of 130°C (KO2). Characteristics quality of the chitosan mud crab shell produced are KO1: yield 61.00%, moisture content 6.47%, ash content 17.18% (db), and degree of deacetylation 49.63%. KO2: yield 59.94%, moisture content 6.48%, ash content 14.85% (db) with degree of deacetylation 51.13%. KO3: yield 53,97, moisture content 6.54%, ash content 14.66% (db) and degree of deacetylation 52.63%. Characteristic quality of chitin included yield was 27.81%, moisture content 7.29%, ash 44.05%, and degree of deacetylation 33.09%.

Study of Growth and Survival of Mud Crab (Scylla serrata, Forskal) with Different Salinity Levels in culture media

The aim of this study to find out the optimal level of salinity for the growth and survival of the mud crab (Scylla serrata). The weight of crab seeds were about 47.65-51.32 grams and the carapace length ranged from 64.35-71.30 mm, then put into 12 tanks (1 m x 1 m x 0.4 m) with a density of 4 crab seed per tank. During the maintenance of this test, mangrove crab was fed with fresh chicken intestines as much as 10% of its body weight per day. Water changes are carried out more than 150% per week. At the beginning of the experiment, each tank was conditioned to the same water salinity in all experimental units, namely 33 ppt. To see the effect of differences in salinity levels on the growth and survival of mud crabs, 4 treatments were made consisting of (A) 33 ppt salt content, (B) 31 ppt salt content, (C). The salt content is 29 ppt, and (D) the salt content is 27 ppt. From the results of this experiment, it is known that a decrease in the salt content of 4 ppt is the best treatment for the growth of mud crabs, but has no effect on the survival value.