Philippines : In the forefront of the mud crab industry development

Biological evaluation of existing feed formulations for the grow-out culture of the mud crab, Scylla serrata

2025-05-28T08:36:28Z

Biological evaluation of existing feed formulations for the grow-out culture of the mud crab, Scylla serrata Catacutan, Mae R. Quinitio, Emilia T.; Parado-Estepa, Fe Dolores; Coloso, Relicardo M. This study was conducted to identify a formulated pelleted feed for the grow-out culture of the mud crab. A commercial crab feed (CCF) was evaluated together with fish by-catch (FBC) and three test diets (formulated and pelleted) of similar dietary energy (1723 MJ/Kg diet) based on published works. The test diets contained 48% (D-1), 43% (D-2), and 38% (D-3) crude protein (CP), respectively. All the five dietary treatments were fed to crablets (5 to 6 g body weight) that were individually stocked in 60-L tanks. Each dietary treatment was fed to six crabs. Crustaceans grow by molting which is not simultaneous, hence, each crab was monitored daily. After the third molt (M3) survival rates in D-1, D-2 and D-3 ranged from 33%-66% compared with only 16% in FBC, and 0% in CCF where no crab survived to molt for the second time (M2). Nutrients in FBC may not be sufficient to sustain growth and survival, while water stable CCF may lack a feed attractant. Diets D-1, D-2, and D-3 were evaluated in another feeding experiment to identify the basal diet for the crab. All crabs molted until M3 and no significant differences were noted on growth performance between treatments. However, D-1 (48% CP) was identified as the basal diet due to better numerical values observed in terms of feed conversion ratios and specific growth rates.

Diseases affecting wild and farmed mud crab in the Philippines

2025-05-28T08:36:27Z

Diseases affecting wild and farmed mud crab in the Philippines Tendencia, Eleonor; Cabilitasan, Ma. Venuz C. Quinitio, Emilia T.; Parado-Estepa, Fe Dolores; Coloso, Relicardo M. Mortalities due to cannibalism and diseases have been reported as major problems in the grow-out phase of mud crab production. This study aimed to identify and describe diseases affecting farmed and wild mud crab (mangrove crab) including predisposing, risk and protective factors, and possible prevention and control measures. A total of 767 wild and farmed mud crab samples were collected. External examination showed abnormalities such as short abdominal flap, discoloration of the abdominal region, darker carapace, lesions on carapace, claws and legs, and presence of epibionts like algae and the barnacles Balanus sp. on the carapace. Internally, necrotic, black and brown gills, and discolored gonads were observed. Stalked barnacles, Octolasmis spp., were observed in the gills. White spot syndrome virus (WSSV) was detected in 14 samples sourced from farms and Infectious hypodermal and haematopoietic necrosis virus (IHHNV) in 2 wild samples. WSSV was implicated in mortality cases. Low temperature and presence of WSSV positive shrimp were identified as risk factors for WSSV infection or outbreak. Pathogenicity tests for some isolated bacteria suggested that these may cause mortality in mud crab under stressful conditions. To prevent mortality due to WSSV infection, it is recommended to avoid polyculture of mud crab with shrimp and/or other crustaceans.

Initiatives on mud crab culture at the Palawan Aquaculture Corporation

2022-09-06T03:00:32Z

Initiatives on mud crab culture at the Palawan Aquaculture Corporation Tech, Elsie; Emboltorio, Cheryl; Galila, Domingo; Ogsimer, Cornelio; Lim, Kimberly Quinitio, Emilia T.; Parado-Estepa, Fe Dolores; Coloso, Relicardo M. Mud crab (Scylla spp) has long been a prime commodity in both local and global market and is regarded as one of the important high-value crustacean species produced in the Philippines. Decades ago, its culture basically relied on the availability of wild seedstock collected and grown to marketable size, or on wild lean adult crabs that were fattened for a short period. Developments and refinements in the hatchery and nursery techniques paved the way to bringing up culture activities to commercial levels. The Palawan Aquaculture Corporation embarked on mud crab culture in the mid 2014 where initial trials started. Collaboration with SEAFDEC/AQD was later forged bringing forth improvements in the hatchery, nursery and grow-out culture. Hatchery-reared juvenile crabs are now being sold. Abstract only.

Growth, survival, proximate and fatty acid composition of sandworm Perinereis quatrefagesi (Grube, 1878) fed variable feed types

2022-09-06T03:00:43Z

Growth, survival, proximate and fatty acid composition of sandworm Perinereis quatrefagesi (Grube, 1878) fed variable feed types Biñas, Joseph B.; Alava, Veronica R.; Campos, Wilfredo L. Quinitio, Emilia T.; Parado-Estepa, Fe Dolores; Coloso, Relicardo M. Sandworm Perinereis quatrefagesi has been used as feed for crustacean broodstock due to its reproductive-enhancing properties particularly protein and highly unsaturated fatty acids (HUFAs). Juvenile sandworms collected along the coast of Guimbal, Iloilo were reared in tanks and fed three nutritionally variable feed types: fish fecal waste, fish meal and rice bran. After 56 days, feeds affected (p<0.05) sandworm growth and crude fat contents but not (p<0.05) survival and crude protein levels. Survival rates were 86~c3 to 89~c5% while crude protein levels were 57.0 ~c 2.5 to 68.0 ~c 5.3 g 100 g^-1 dry weight. High crude protein fish meal promoted better (p<0.05) growth (2.2~c0.4% day^-1) than fish feces (1.2~c0.3% day^-1) and rice bran (1.1~c0.3 % day^-1). However, crude fat content of sandworm was higher (p<0.05) in rice bran (18.9~c1.6 g 100 g^-1) than in fecal waste (13.6~c2.9 g 100 g^-1) and fish meal (10.5~c3.1 g 100 g^-1) treatments. Levels of highly unsaturated fatty acids (HUFAs) such as 20:4 n-6, 22:6 n-3 and 20:5 n-3 did not differ significantly (p>0.05) at 0.41~c0.21 to 0.89~c0.51 g 100 g^-1, 0.21~c0.24 to 0.43~c0.22 g 100 g^-1 and 0.57~c0.46 to 0.88~c0.31 g 100 g^-1, respectively. The study demonstrated that P. quatrefagesi: (1) can survive well in nutritionally variable feed types although it grows better in high protein diet; (2) crude protein levels were high regardless of feed types; and (3) crude fat content was high in high fat diet but n-3 and n-6 HUFAs were not significantly different regardless of feed types. Abstract only.