Red clawcrayfish (RCC)were first introduced for culture in Thailand in the early 1990s in Kanchanaburi province, west of Bangkok. In the year 2006 RCC co-culture with rice was endorsed and promoted under the Royal Developmental Projects to supplement the income of rice farmers. Thus, commercial scale RCC culture can be found in Thai provinces such as Bangkok (central), Kanchanaburi (western near the Burmese border), Chiangmai (northern) and Sakaew (eastern near the Cambodian border). In Sakaew, the general practice in RCC culture is to stock RCC broodstock aged more than 9 months in freshwater ponds at a density of approximately 1.8–2/m2 (i.e., 1500 brooders in a 20 × 40 m2 pond). The ratio of males:females is 1:3. The brooders are fed once a day with a commercial BTS feed designed for shrimp of a similar size and supplemented with living freshwater shrimp Macrobrachium lanchesteri in the family Palaemonidae. After mating,
the females carrying fertilized eggs (berried females) are transferred to concrete tanks in a dark, closed house until the eggs are nearly hatched (i.e., red in color with black eye spots). The females are then placed individually in porous plastic cages until all eggs are hatched
and until the initially dependent larvae escape from the cages as juvenile crayfish that are independent from their mothers and not vulnerable to cannibalism by her. The mother crayfish are then moved back to resting ponds and after full recovery, eventually to brooder ponds again. Meanwhile, the juvenile RCC are moved to nursery ponds which generally consist of rice fields modified such that approximately ¼of the area at one end is dug deeper than the rest of the field (approximately 70 cm deep). No rice is grown in this area. Instead, coconut leaves or plastic mesh (onion sack like material/roofing material) are placed in thewater to provide shelter for the crayfish. Generally, the juvenile RCC are transferred to the rice field after the rice seedlings have been planted for at least 45 days. They are raised in this pond for
about 45 days before they are sold to rice farmers to stock in their rice fields. The rice fields that are used as growout ponds for RCC are similar to those used to raise the juvenile RCC but larger. Stocking density is approximately 5000 RCC/rai (1 rai=1600m2). They generally eat natural food supplemented with P. monodon pelleted feed at 1.5% body weight once a day in the evening until harvested at the 4th month (~50 g) or at the 8th month (~100 g) after stocking. The 4-month period of RCC culture is approximately the same as that for harvesting the rice (i.e., managed so that the RCC and rice can be harvested at the same time). Generally, female RCC are harvested during this time while males are cultured onward in other rice fields prepared nearby for an additional 4months to obtain larger sizes. Female RCC growvery slowly
after reaching maturity and are not considered economically viable to keep after 4 months, except for use as brooders. RCC are harvested live and transported in foamboxes to restaurants throughout the country. Some are sold as ornamental or aquarium animals (especially small
juvenile stages). Depending on size, farmers can earn 400–800 Thai Baht for 1 kg of RCC sold to restaurants.
สีแดง clawcrayfish (RCC) ก่อนถูกนำในวัฒนธรรมในประเทศไทยในช่วงปี 1990 ในจังหวัดกาญจนบุรี ทางตะวันตกของกรุงเทพมหานคร ในปี 2006 RCC ร่วมวัฒนธรรมข้าวได้รับรอง และส่งเสริมภายใต้โครงการพัฒนารอยัลเสริมรายได้ของเกษตรกรข้าว ดังนั้น พาณิชย์ระดับวัฒนธรรม RCC สามารถพบในจังหวัดเช่นกรุงเทพมหานคร (กลาง), กาญจนบุรี (ตะวันตกใกล้กับชายแดนพม่า), เชียงใหม่ (ภาคเหนือ) และสระแก้ว (ตะวันออกใกล้กับชายแดนกัมพูชา) ในสระแก้ว การฝึกทั่วไปในวัฒนธรรม RCC จะสูตร RCC หุ้นอายุมากกว่า 9 เดือนในบ่อปลาที่ความหนาแน่นของประมาณ 1.8 – 2/m2 (เช่น 1500 brooders ในบ่อ 20 × 40 m2) อัตราส่วนของชาย: หญิงเป็น 1:3 Brooders การเลี้ยงเมื่อวันฟ้าเชิงพาณิชย์ที่เลี้ยงมากุ้งขนาดใกล้เคียงกัน และเสริม ด้วย lanchesteri ก้ามกุ้งน้ำจืดอยู่ในครอบครัว Palaemonidae หลังจากผสมพันธุ์หญิงไข่สแตนถือครองปฏิสนธิ (berried หญิง) ถูกโอนย้ายไปถังคอนกรีตในบ้านมืด ปิดจนเกือบจะฟักไข่ (เช่น แดงสีมีจุดตาสีดำ) หญิงถูกจัดอยู่ละใน porous พลาสติกกรงจนกว่าจะฟักไข่ทั้งหมดand until the initially dependent larvae escape from the cages as juvenile crayfish that are independent from their mothers and not vulnerable to cannibalism by her. The mother crayfish are then moved back to resting ponds and after full recovery, eventually to brooder ponds again. Meanwhile, the juvenile RCC are moved to nursery ponds which generally consist of rice fields modified such that approximately ¼of the area at one end is dug deeper than the rest of the field (approximately 70 cm deep). No rice is grown in this area. Instead, coconut leaves or plastic mesh (onion sack like material/roofing material) are placed in thewater to provide shelter for the crayfish. Generally, the juvenile RCC are transferred to the rice field after the rice seedlings have been planted for at least 45 days. They are raised in this pond forabout 45 days before they are sold to rice farmers to stock in their rice fields. The rice fields that are used as growout ponds for RCC are similar to those used to raise the juvenile RCC but larger. Stocking density is approximately 5000 RCC/rai (1 rai=1600m2). They generally eat natural food supplemented with P. monodon pelleted feed at 1.5% body weight once a day in the evening until harvested at the 4th month (~50 g) or at the 8th month (~100 g) after stocking. The 4-month period of RCC culture is approximately the same as that for harvesting the rice (i.e., managed so that the RCC and rice can be harvested at the same time). Generally, female RCC are harvested during this time while males are cultured onward in other rice fields prepared nearby for an additional 4months to obtain larger sizes. Female RCC growvery slowlyafter reaching maturity and are not considered economically viable to keep after 4 months, except for use as brooders. RCC are harvested live and transported in foamboxes to restaurants throughout the country. Some are sold as ornamental or aquarium animals (especially smalljuvenile stages). Depending on size, farmers can earn 400–800 Thai Baht for 1 kg of RCC sold to restaurants.
การแปล กรุณารอสักครู่..
