Species composition and nutritive value of shelled mollusks of Pampanga Bay

• Main Author: Ongtangco, Remedios Eugenio
• Format: text
• Language: English
• Published: Animo Repository 1992
• Subjects: Mollusks—Variation—Philippines—Pampanga Bay; Water—Analysis; Biology
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/1496; https://animorepository.dlsu.edu.ph/cgi/viewcontent.cgi?article=8334&context=etd_masteral
• Institution: De La Salle University

A study of shelled mollusks gathered in Pampanga Bay, Central Luzon, Philippines was conducted in May to October 1991 to determine their species composition and nutritive value and to describe the substratum and water quality where they are found.These shelled mollusks locally known as gasang are currently being used as supplemental prawn feeds in Central Luzon. Gasang is a collection of shells composed of two bivalves belonging to Family Tellinidae, Omala hyalina., Cadella narutoensis and a gastropod belonging to Family Thiaridae, Melanoides plicaria.Water quality determined at two sites in Sasmuan, Pampanga (where shell gathering occurs) gave recorded values of 29-31 degrees C temperature, 4.4-5.8 mg/l dissolved oxygen, 13.8-16.6 ppt salinity, 2.75 mg/l ammonia - nitrogen and 7.7-8.3 pH units.Soil collected at average depth of 6.9-8.1 m is composed of 77-88 percent silt, 9-19 percent sand and 2-4 percent clay.Recorded mean values for crude protein (2.78-5.37 percent) and fat (1.6-2.5 percent) in shelled mollusks were comparatively lower than commercial feed ingredients but higher levels of Ca (23.2 percent), Mn (0.0677-0.1220 percent), Mg (1.60 percent), Fe (0.1519-0.1716 percent), Cu (0.0015-0.0029 percent), Zn (0.0015-0.0029 percent), and P (1.1004-1.1650 percent) were noted. Trace elements of K (0.1743-0.2906 percent), SiO (1.800 percent), and Co (0.0106 percent) were also noted.