{"id":4590,"date":"2015-11-30T07:12:43","date_gmt":"2015-11-30T00:12:43","guid":{"rendered":"http:\/\/ttud.com.vn\/?p=4590"},"modified":"2017-10-02T09:39:22","modified_gmt":"2017-10-02T02:39:22","slug":"ung-dung-mot-so-cong-nghe-moi-trong-nuoi-trong-thuy-san","status":"publish","type":"post","link":"https:\/\/casta.ttud.com.vn\/index.php\/ung-dung-mot-so-cong-nghe-moi-trong-nuoi-trong-thuy-san\/","title":{"rendered":"\u1ee8NG D\u1ee4NG M\u1ed8T S\u1ed0 C\u00d4NG NGH\u1ec6 M\u1edaI TRONG NU\u00d4I TR\u1ed2NG TH\u1ee6Y S\u1ea2N"},"content":{"rendered":"

\u0110\u1ec3 x\u00e2y d\u1ef1ng c\u00e1c m\u00f4 h\u00ecnh nu\u00f4i ph\u00e1t tri\u1ec3n b\u1ec1n v\u1eefng, th\u00e2n thi\u1ec7n v\u1edbi m\u00f4i tr\u01b0\u1eddng, xu h\u01b0\u1edbng hi\u1ec7n nay l\u00e0 \u0111\u1ea9y m\u1ea1nh vi\u1ec7c \u00e1p d\u1ee5ng c\u00e1c bi\u1ec7n ph\u00e1p k\u1ef9 thu\u1eadt v\u00e0 sinh h\u1ecdc t\u00e1c \u0111\u1ed9ng nh\u1eb1m l\u00e0m t\u0103ng hi\u1ec7u qu\u1ea3 s\u1eed d\u1ee5ng ngu\u1ed3n t\u00e0i nguy\u00ean n\u01b0\u1edbc th\u00f4ng qua vi\u1ec7c qu\u1ea3n l\u00fd ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc trong h\u1ec7 th\u1ed1ng nu\u00f4i \u0111\u1ec3 t\u1ef1 l\u00e0m s\u1ea1ch v\u00e0 t\u00e1i s\u1eed d\u1ee5ng n\u01b0\u1edbc…<\/strong><\/p>\n

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1. Gi\u1edbi thi\u1ec7u<\/strong><\/p>\n

Ng\u00e0nh nu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n c\u00f3 vai tr\u00f2 \u0111\u1eb7c bi\u1ec7t quan tr\u1ecdng trong chi\u1ebfn l\u01b0\u1ee3c ph\u00e1t tri\u1ec3n kinh t\u1ebf – x\u00e3 h\u1ed9i \u1edf Vi\u1ec7t Nam. Trong nh\u1eefng n\u0103m qua, s\u1ea3n xu\u1ea5t th\u1ee7y s\u1ea3n \u0111\u00e3 \u0111\u1ea1t nh\u1eefng th\u00e0nh t\u1ef1u r\u1ea5t l\u1edbn. Trong n\u0103m 2011, t\u1ed5ng s\u1ea3n l\u01b0\u1ee3ng th\u1ee7y s\u1ea3n \u0111\u1ea1t tr\u00ean 5,2 tri\u1ec7u t\u1ea5n (t\u0103ng g\u1ea5p 5,1 l\u1ea7n so v\u1edbi n\u0103m 1990, b\u00ecnh qu\u00e2n t\u0103ng 8,49%\/n\u0103m); s\u1ea3n l\u01b0\u1ee3ng nu\u00f4i tr\u1ed3ng \u0111\u1ea1t 3 tri\u1ec7u t\u1ea5n (t\u0103ng g\u1ea5p 9,7 l\u1ea7n so v\u1edbi n\u0103m 1990, b\u00ecnh qu\u00e2n t\u0103ng 12,02%\/n\u0103m). Trong th\u1eddi gian t\u1edbi, nu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n n\u01b0\u1edbc ng\u1ecdt \u1edf \u0110BSCL ph\u1ea3i \u0111\u1ed1i m\u1eb7t v\u1edbi nh\u1eefng th\u00e1ch th\u1ee9c m\u1edbi nh\u01b0 suy gi\u1ea3m t\u00e0i nguy\u00ean n\u01b0\u1edbc ng\u1ecdt do bi\u1ebfn \u0111\u1ed5i m\u00f4i tr\u01b0\u1eddng \u0111\u1ea7u ngu\u1ed3n s\u00f4ng Mekong, x\u00e2m nh\u1eadp m\u1eb7n l\u00e0m gi\u1ea3m di\u1ec7n t\u00edch nu\u00f4i th\u1ee7y s\u1ea3n n\u01b0\u1edbc ng\u1ecdt, trong khi nhu c\u1ea7u s\u1ea3n ph\u1ea9m th\u1ee7y s\u1ea3n ng\u00e0y c\u00e0ng t\u0103ng. \u0110\u1ec3 \u0111\u00e1p \u1ee9ng nhu c\u1ea7u gia t\u0103ng s\u1ea3n l\u01b0\u1ee3ng, ngh\u1ec1 nu\u00f4i th\u1ee7y s\u1ea3n n\u01b0\u1edbc ng\u1ecdt \u0111ang ph\u00e1t tri\u1ec3n theo h\u01b0\u1edbng \u0111a d\u1ea1ng h\u00f3a v\u00e0 th\u00e2m canh h\u00f3a. Tuy nhi\u00ean, th\u00e2m canh h\u00f3a ngh\u1ec1 nu\u00f4i c\u0169ng s\u1ebd \u0111\u1ed1i m\u1eb7t v\u1edbi nhi\u1ec1u m\u1ed1i nguy nh\u01b0 t\u0103ng s\u1eed d\u1ee5ng t\u00e0i nguy\u00ean n\u01b0\u1edbc, gia t\u0103ng \u00f4 nhi\u1ec5m m\u00f4i tr\u01b0\u1eddng, d\u1ecbch b\u1ec7nh d\u1ec5 ph\u00e1t sinh v\u00e0 kh\u00f3 ki\u1ec3m so\u00e1t. Do v\u1eady, th\u00e2m canh h\u00f3a ph\u1ea3i g\u1eafn li\u1ec1n v\u1edbi kh\u00e1i ni\u1ec7m nu\u00f4i b\u1ec1n v\u1eefng. \u0110\u00f3 l\u00e0 s\u1ef1 qu\u1ea3n l\u00fd th\u00e0nh c\u00f4ng m\u00f4 h\u00ecnh s\u1ea3n xu\u1ea5t th\u1ee7y s\u1ea3n \u0111\u00e1p \u1ee9ng nhu c\u1ea7u c\u1ee7a con ng\u01b0\u1eddi, trong khi v\u1eabn duy tr\u00ec ch\u1ea5t l\u01b0\u1ee3ng m\u00f4i tr\u01b0\u1eddng v\u00e0 b\u1ea3o v\u1ec7 \u0111\u01b0\u1ee3c c\u00e1c ngu\u1ed3n t\u00e0i nguy\u00ean t\u1ef1 nhi\u00ean.<\/p>\n

\u0110\u1ec3 x\u00e2y d\u1ef1ng c\u00e1c m\u00f4 h\u00ecnh nu\u00f4i ph\u00e1t tri\u1ec3n b\u1ec1n v\u1eefng, th\u00e2n thi\u1ec7n v\u1edbi m\u00f4i tr\u01b0\u1eddng, xu h\u01b0\u1edbng hi\u1ec7n nay l\u00e0 \u0111\u1ea9y m\u1ea1nh vi\u1ec7c \u00e1p d\u1ee5ng c\u00e1c bi\u1ec7n ph\u00e1p k\u1ef9 thu\u1eadt v\u00e0 sinh h\u1ecdc t\u00e1c \u0111\u1ed9ng nh\u1eb1m l\u00e0m t\u0103ng hi\u1ec7u qu\u1ea3 s\u1eed d\u1ee5ng ngu\u1ed3n t\u00e0i nguy\u00ean n\u01b0\u1edbc th\u00f4ng qua vi\u1ec7c qu\u1ea3n l\u00fd ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc trong h\u1ec7 th\u1ed1ng nu\u00f4i \u0111\u1ec3 t\u1ef1 l\u00e0m s\u1ea1ch v\u00e0 t\u00e1i s\u1eed d\u1ee5ng n\u01b0\u1edbc; ho\u1eb7c \u1ed5n \u0111\u1ecbnh ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc, c\u00e2n b\u1eb1ng h\u1ec7 sinh v\u1eadt, v\u00e0 b\u1ed5 sung ch\u1ea5t dinh d\u01b0\u1ee1ng. \u0110\u00e2y l\u00e0 c\u01a1 s\u1edf \u0111\u1ec3 ph\u00e1t tri\u1ec3n h\u1ec7 th\u1ed1ng nu\u00f4i t\u00e1i s\u1eed d\u1ee5ng n\u01b0\u1edbc hay h\u1ec7 th\u1ed1ng l\u1ecdc tu\u1ea7n ho\u00e0n (RAS) v\u00e0 \u1ee9ng d\u1ee5ng c\u00f4ng ngh\u1ec7 biofloc.<\/p>\n

2. C\u00f4ng ngh\u1ec7 nu\u00f4i th\u1ee7y s\u1ea3n trong h\u1ec7 th\u1ed1ng l\u1ecdc tu\u1ea7n ho\u00e0n<\/strong><\/p>\n

2.1 Kh\u00e1i ni\u1ec7m h\u1ec7 th\u1ed1ng nu\u00f4i th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n<\/strong>
\nNu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n theo h\u1ec7 th\u1ed1ng nu\u00f4i th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n bao g\u1ed3m m\u1ed9t d\u00e2y chuy\u1ec1n c\u00e1c qu\u00e1 tr\u00ecnh b\u1ed5 sung, cho ph\u00e9p l\u01b0\u1ee3ng n\u01b0\u1edbc th\u1ea3i \u0111\u01b0\u1ee3c t\u00e1i s\u1eed d\u1ee5ng cho b\u1ec3 nu\u00f4i ho\u1eb7c m\u1ed9t b\u1ec3 nu\u00f4i kh\u00e1c (Timmons et al., 2002). Trong h\u1ec7 th\u1ed1ng nu\u00f4i th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n, ph\u00e2n bi\u1ec7t:<\/p>\n

– H\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n n\u01b0\u1edbc m\u1ed9t ph\u1ea7n l\u00e0 h\u1ec7 th\u1ed1ng c\u00f3 t\u1eeb 10 \u2013 70 % l\u01b0\u1ee3ng n\u01b0\u1edbc tu\u1ea7n ho\u00e0n trong m\u1ed9t chu k\u1ef3 (m\u1ed7i ng\u00e0y).<\/p>\n

– H\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n n\u01b0\u1edbc ho\u00e0n to\u00e0n l\u00e0 h\u1ec7 th\u1ed1ng thay n\u01b0\u1edbc \u00edt h\u01a1n 10 % th\u1ec3 t\u00edch n\u01b0\u1edbc c\u1ee7a h\u1ec7 th\u1ed1ng nu\u00f4i m\u1ed7i ng\u00e0y.<\/p>\n

2.2. M\u1ee5c \u0111\u00edch x\u00e2y d\u1ef1ng h\u1ec7 th\u1ed1ng nu\u00f4i th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n<\/strong>
\nTheo Hochheimer and Wheaton (1998), vi\u1ec7c x\u00e2y d\u1ef1ng h\u1ec7 th\u1ed1ng nu\u00f4i th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n nh\u1eb1m \u0111\u1ea1t c\u00e1c m\u1ee5c \u0111\u00edch:<\/p>\n

– \u0110\u1ea3m b\u1ea3o qu\u00e1 tr\u00ecnh v\u1eadn h\u00e0nh an to\u00e0n, ki\u1ec3m so\u00e1t m\u1ea7m b\u1ec7nh, s\u1ee9c kh\u1ecfe v\u00e0 ch\u1ea5t l\u01b0\u1ee3ng s\u1ea3n ph\u1ea9m c\u00e1 nu\u00f4i.<\/p>\n

– Gi\u1ea3m thi\u1ec3u t\u1ed1i \u0111a l\u01b0\u1ee3ng n\u01b0\u1edbc \u0111\u01b0\u1ee3c thay trong th\u1eddi gian nu\u00f4i, t\u0103ng s\u1ea3n l\u01b0\u1ee3ng c\u00e1 nu\u00f4i.<\/p>\n

– C\u1ea3i thi\u1ec7n v\u00e0 l\u00e0m gia t\u0103ng t\u1ed1c \u0111\u1ed9 t\u0103ng tr\u01b0\u1edfng cao nh\u1ea5t, ch\u1ea5t l\u01b0\u1ee3ng c\u00e1 v\u00e0 hi\u1ec7u qu\u1ea3 s\u1ea3n xu\u1ea5t t\u1ed5ng th\u1ec3.<\/p>\n

– Cho ph\u00e9p x\u1eed l\u00fd n\u01b0\u1edbc \u00f4 nhi\u1ec5m trong m\u1ed9t v\u00f9ng kh\u00e9p k\u00edn v\u00e0 gi\u00fap n\u00e2ng cao ki\u1ec3m so\u00e1t qu\u00e1 tr\u00ecnh x\u1ea3 th\u1ea3i, g\u00f3p ph\u1ea7n b\u1ea3o v\u1ec7 m\u00f4i tr\u01b0\u1eddng.<\/p>\n

– H\u00ecnh th\u00e0nh v\u00e0 ph\u00e1t tri\u1ec3n c\u00f4ng ngh\u1ec7 nu\u00f4i t\u1ea1o ra s\u1ea3n ph\u1ea9m s\u1ea1ch, ch\u1ea5t l\u01b0\u1ee3ng v\u00e0 b\u1ea3o v\u1ec7 m\u00f4i tr\u01b0\u1eddng, \u0111\u00e1p \u1ee9ng nhu c\u1ea7u c\u1ee7a ng\u01b0\u1eddi ti\u00eau d\u00f9ng.<\/p>\n

– Ti\u1ebft ki\u1ec7m \u0111\u01b0\u1ee3c di\u1ec7n t\u00edch \u0111\u1ea5t khai th\u00e1c v\u00e0 th\u1eddi gian ch\u0103m s\u00f3c, qu\u1ea3n l\u00fd h\u1ec7 th\u1ed1ng nu\u00f4i.<\/p>\n

2.3. C\u1ea5u tr\u00fac c\u1ee7a h\u1ec7 th\u1ed1ng nu\u00f4i th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n<\/strong>
\nM\u1ed9t h\u1ec7 th\u1ed1ng nu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n, t\u00f9y theo qui m\u00f4, nh\u01b0ng th\u01b0\u1eddng bao g\u1ed3m m\u1ed9t s\u1ed1 b\u1ec3 nu\u00f4i c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng th\u1ee7y s\u1ea3n, b\u1ec3 t\u00e1ch ch\u1ea5t th\u1ea3i r\u1eafn (TSS), b\u1ec3 ch\u1ee9a v\u1edbi m\u00e1y b\u01a1m v\u00e0 b\u1ec3 l\u1ecdc sinh h\u1ecdc. Ngo\u00e0i ra, \u1edf h\u1ec7 th\u1ed1ng nu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n c\u00f3 th\u1ec3 c\u00f3 th\u00eam m\u1ed9t ho\u1eb7c c\u00e1c b\u1ed9 ph\u1eadn tr\u1ee3 l\u1ef1c kh\u00e1c nh\u01b0: b\u1ec3 ph\u1ea3n nitrate, d\u1ee5ng c\u1ee5 kh\u1eed tr\u00f9ng, b\u1ec3 periphyton ho\u1eb7c b\u1ec3 ch\u1ee9a rong b\u00e8o v\u00e0 sau c\u00f9ng l\u00e0 b\u1ec3 \u01b0\u01a1ng hay d\u01b0\u1ee1ng c\u00e1 kh\u1ecfe, \u0111\u1ea1t ti\u00eau chu\u1ea9n k\u00edch th\u01b0\u1edbc tr\u01b0\u1edbc khi th\u1ea3 nu\u00f4i v\u00e0o h\u1ec7 th\u1ed1ng.<\/p>\n

2.4. C\u00e1c m\u00f4 h\u00ecnh nu\u00f4i th\u1ee7y s\u1ea3n trong h\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n tr\u00ean th\u1ebf gi\u1edbi v\u00e0 t\u1ea1i Vi\u1ec7t Nam<\/strong><\/p>\n

K\u1ec3 t\u1eeb nh\u1eefng n\u0103m 80, nu\u00f4i c\u00e1 b\u1eb1ng h\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n n\u01b0\u1edbc \u0111\u00e3 t\u0103ng l\u00ean \u0111\u00e1ng k\u1ec3 v\u1ec1 kh\u1ed1i l\u01b0\u1ee3ng v\u00e0 \u0111a d\u1ea1ng lo\u00e0i (Rosenthal, 1980; Verreth and Eding, 1993; Martins et al., 2005). Ng\u00e0y nay h\u01a1n 10 lo\u00e0i c\u00e1 \u0111\u01b0\u1ee3c s\u1ea3n xu\u1ea5t theo c\u00f4ng ngh\u1ec7 h\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n n\u01b0\u1edbc (c\u00e1 tr\u00ea phi, l\u01b0\u01a1n, c\u00e1 ch\u00ecnh, c\u00e1 r\u00f4 phi, c\u00e1 b\u01a1n, c\u00e1 ch\u1ebdm,..). N\u0103ng su\u1ea5t nu\u00f4i c\u00e1 tr\u00ea phi c\u00f3 th\u1ec3 \u0111\u1ea1t 500kg\/m3\/v\u1ee5, c\u00e1 ch\u00ecnh kho\u1ea3ng 600 t\u1ea5n\/m3\/v\u1ee5 v\u00e0 c\u00e1 r\u00f4 phi l\u00e0 140 kg\/m3\/v\u1ee5.<\/p>\n

Nhi\u1ec1u b\u00e1o c\u00e1o cho th\u1ea5y r\u1eb1ng s\u1ea3n xu\u1ea5t gi\u1ed1ng ng\u00e0y c\u00e0ng \u00e1p d\u1ee5ng theo c\u00f4ng ngh\u1ec7 h\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n n\u01b0\u1edbc. V\u00ed d\u1ee5 s\u1ea3n xu\u1ea5t gi\u1ed1ng c\u00e1 h\u1ed3i \u0110\u1ea1i T\u00e2y D\u01b0\u01a1ng \u1edf \u0111\u1ea3o Faeroe ho\u00e0n to\u00e0n \u00e1p d\u1ee5ng theo c\u00f4ng ngh\u1ec7 RAS t\u1eeb sau n\u0103m 2000 (Bergheim et al., 2008, 2009). T\u1ea1i Na Uy d\u1ef1 ki\u1ebfn s\u1ea3n xu\u1ea5t 85 tri\u1ec7u gi\u1ed1ng c\u00e1 h\u1ed3i theo c\u00f4ng ngh\u1ec7 h\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n n\u01b0\u1edbc (Del campo et al., 2010). T\u00ecnh tr\u1ea1ng thi\u1ebfu n\u01b0\u1edbc trong t\u01b0\u01a1ng lai, nhi\u1ec7t \u0111\u1ed9 theo m\u00f9a thay \u0111\u1ed5i l\u1edbn l\u00e0 nh\u1eefng y\u1ebfu t\u1ed1 chuy\u1ec3n s\u1ea3n xu\u1ea5t gi\u1ed1ng c\u00e1 h\u1ed3i theo c\u00f4ng ngh\u1ec7 h\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n n\u01b0\u1edbc \u1edf Na Uy (Kristensen et al., 2009).<\/p>\n

\u1ede Vi\u1ec7t Nam tr\u01b0\u1edbc \u0111\u00e2y, c\u00f4ng ngh\u1ec7 nu\u00f4i tu\u1ea7n ho\u00e0n n\u00e0y ch\u01b0a \u0111\u01b0\u1ee3c quan t\u00e2m. Tuy nhi\u00ean, do vi\u1ec7c \u00e1p d\u1ee5ng nh\u1eefng ti\u00eau chu\u1ea9n m\u1edbi v\u1ec1 s\u1ea3n ph\u1ea9m th\u1ee7y s\u1ea3n c\u1ee7a nh\u1eefng nh\u00e0 nh\u1eadp kh\u1ea9u Ch\u00e2u \u00c2u v\u00e0 M\u1ef9 trong \u0111\u00f3 c\u00f3 vi\u1ec7c qu\u1ea3n l\u00fd ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc nh\u01b0 l\u00e0m gi\u1ea3m l\u01b0\u1ee3ng d\u01b0\u1ee1ng ch\u1ea5t th\u1ea3i ra m\u00f4i tr\u01b0\u1eddng, n\u00ean vi\u1ec7c \u00e1p d\u1ee5ng nu\u00f4i th\u1ee7y s\u1ea3n trong h\u1ec7 th\u1ed1ng RAS \u0111\u00e3 b\u1eaft \u0111\u1ea7u \u0111\u01b0\u1ee3c quan t\u00e2m. C\u00f4ng ngh\u1ec7 n\u00e0y \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng nhi\u1ec1u nh\u1ea5t trong l\u0129nh v\u1ef1c s\u1ea3n xu\u1ea5t gi\u1ed1ng c\u00e1, t\u00f4m. Hi\u1ec7n t\u1ea1i qua th\u1eddi gian th\u1eed nghi\u1ec7m, Tr\u01b0\u1eddng \u0110\u1ea1i h\u1ecdc C\u1ea7n Th\u01a1 \u0111\u00e3 \u0111\u01b0a k\u1ef9 thu\u1eadt nu\u00f4i tu\u1ea7n ho\u00e0n v\u00e0o ch\u01b0\u01a1ng tr\u00ecnh gi\u1ea3ng d\u1ea1y cho b\u1eadc \u0110\u1ea1i h\u1ecdc v\u00e0 Cao h\u1ecdc. Ngo\u00e0i ra, c\u00e1c th\u00ed nghi\u1ec7m x\u00e2y d\u1ef1ng quy tr\u00ecnh nu\u00f4i c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng nu\u00f4i ph\u1ed5 bi\u1ebfn nh\u01b0: c\u00e1 Tra, L\u00f3c, Tr\u00ea, R\u00f4 \u0111\u1ed3ng, \u2026 b\u1eb1ng h\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n n\u01b0\u1edbc c\u0169ng \u0111\u00e3 \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n v\u00e0 cho k\u1ebft qu\u1ea3 ban \u0111\u1ea7u r\u1ea5t kh\u1ea3 quan. Trong qu\u00e1 tr\u00ecnh th\u1ef1c nghi\u1ec7m nu\u00f4i c\u00e1 Tra trong h\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n, v\u1edbi m\u1eadt \u0111\u1ed9 th\u1ea3 2.000 con\/m3, th\u1ee9c \u0103n cung c\u1ea5p c\u00f3 40 % \u0111\u1ea1m, th\u1ef1c nghi\u1ec7m cho t\u1ec9 l\u1ec7 s\u1ed1ng kh\u00f4ng thay \u0111\u1ed5i sau 56 ng\u00e0y nu\u00f4i, v\u1edbi t\u1ed1c \u0111\u1ed9 t\u0103ng tr\u01b0\u1edfng \u0111\u1eb7c bi\u1ec7t \u0111\u1ea1t b\u00ecnh qu\u00e2n 4,32 %\/ng\u00e0y. \u0110\u1ed1i v\u1edbi c\u00e1 L\u00f3c, v\u1edbi kh\u1ed1i l\u01b0\u1ee3ng ban \u0111\u1ea7u th\u1ea3 nu\u00f4i l\u00e0 2,5 g\/con, m\u1eadt \u0111\u1ed9 th\u1ea3 250 con\/m3, sau 150 ng\u00e0y th\u1ea3 nu\u00f4i, t\u0103ng tr\u01b0\u1edfng c\u1ee7a c\u00e1 \u0111\u1ea1t b\u00ecnh qu\u00e2n 2,57 g\/ng\u00e0y v\u00e0 kh\u1ed1i l\u01b0\u1ee3ng trung b\u00ecnh c\u1ee7a c\u00e1 khi thu ho\u1ea1ch \u0111\u1ea1t b\u00ecnh qu\u00e2n 387 g\/con. \u1ede c\u1ea3 hai th\u1ef1c nghi\u1ec7m tr\u00ean, \u0111i\u1ec1u ki\u1ec7n m\u00f4i tr\u01b0\u1eddng n\u01b0\u1edbc bi\u1ec3u hi\u1ec7n kh\u00e1 \u1ed5n \u0111\u1ecbnh, kh\u00f4ng g\u00e2y \u1ea3nh h\u01b0\u1edfng b\u1ea5t l\u1ee3i cho s\u1ef1 sinh tr\u01b0\u1edfng v\u00e0 ph\u00e1t tri\u1ec3n c\u1ee7a c\u00e1.<\/p>\n

2.5. Nh\u1eefng thu\u1eadn l\u1ee3i v\u00e0 kh\u00f3 kh\u0103n khi \u00e1p d\u1ee5ng h\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n trong nu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n<\/strong><\/p>\n

Thu\u1eadn l\u1ee3i<\/strong>
\nTheo m\u1ed9t s\u1ed1 c\u00f4ng tr\u00ecnh nghi\u00ean c\u1ee9u v\u00e0 th\u1ef1c nghi\u1ec7m cho th\u1ea5y h\u1ec7 th\u1ed1ng h\u1ec7 th\u1ed1ng nu\u00f4i th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n mang l\u1ea1i r\u1ea5t nhi\u1ec1u l\u1ee3i \u00edch nh\u01b0:<\/p>\n

– Y\u00eau c\u1ea7u n\u01b0\u1edbc cung c\u1ea5p cho h\u1ec7 th\u1ed1ng nu\u00f4i th\u1ea5p: B\u1edfi v\u00ec h\u1ec7 th\u1ed1ng nu\u00f4i th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n t\u00e1i ch\u1ebf h\u1ea7u h\u1ebft l\u01b0\u1ee3ng n\u01b0\u1edbc \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng, l\u01b0\u1ee3ng n\u01b0\u1edbc \u0111\u01b0\u1ee3c b\u1ed5 sung r\u1ea5t \u00edt.<\/p>\n

– Y\u00eau c\u1ea7u v\u1ec1 di\u1ec7n t\u00edch nh\u1ecf: C\u00e1 \u0111\u01b0\u1ee3c nu\u00f4i trong b\u1ec3, v\u1edbi oxy \u0111\u01b0\u1ee3c cung c\u1ea5p v\u00e0 ch\u1ea5t th\u1ea3i trong qu\u00e1 tr\u00ecnh trao \u0111\u1ed5i ch\u1ea5t c\u1ee7a c\u00e1 nu\u00f4i \u0111\u01b0\u1ee3c lo\u1ea1i b\u1ecf, c\u00e1 \u0111\u01b0\u1ee3c th\u1ea3 \u1edf m\u1eadt \u0111\u1ed9 cao. V\u00ec v\u1eady, h\u1ec7 th\u1ed1ng nu\u00f4i th\u1ee7y s\u1ea3n tu\u1ea7n ho\u00e0n c\u00f3 th\u1ec3 ti\u1ebft ki\u1ec7m \u0111\u01b0\u1ee3c m\u1ed9t di\u1ec7n t\u00edch \u0111\u00e1ng k\u1ec3, nh\u01b0ng v\u1eabn \u0111\u1ea3m b\u1ea3o \u0111\u01b0\u1ee3c n\u0103ng su\u1ea5t, s\u1ea3n l\u01b0\u1ee3ng c\u00e1 cho nhu c\u1ea7u ti\u00eau d\u00f9ng.<\/p>\n

– Ki\u1ec3m so\u00e1t \u0111\u01b0\u1ee3c ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc: V\u1edbi h\u1ec7 th\u1ed1ng tu\u1ea7n ho\u00e0n, ng\u01b0\u1eddi nu\u00f4i s\u1ebd ch\u1ee7 \u0111\u1ed9ng ki\u1ec3m so\u00e1t v\u00e0 qu\u1ea3n l\u00fd ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc ph\u00f9 h\u1ee3p cho s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a c\u00e1 trong qu\u00e1 tr\u00ecnh nu\u00f4i.<\/p>\n

– Kh\u1ed1ng ch\u1ebf d\u1ecbch b\u1ec7nh: Vi\u1ec7c ki\u1ec3m so\u00e1t m\u00f4i tr\u01b0\u1eddng k\u1ebft h\u1ee3p th\u1ef1c hi\u1ec7n vi\u1ec7c cung c\u1ea5p th\u1ee9c \u0103n cho h\u1ec7 th\u1ed1ng nu\u00f4i h\u1ee3p l\u00fd, gi\u00fap cho c\u00f4ng t\u00e1c ph\u00f2ng b\u1ec7nh t\u1ed1t h\u01a1n, c\u00e1 \u00edt b\u1ecb nhi\u1ec5m b\u1ec7nh trong qu\u00e1 tr\u00ecnh \u01b0\u01a1ng nu\u00f4i.<\/p>\n

Kh\u00f3 kh\u0103n<\/strong>
\nVi\u1ec7c qu\u1ea3n l\u00fd ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc ph\u1ea3i \u0111\u1ea3m b\u1ea3o nghi\u00eam ng\u1eb7t, v\u00ec s\u1ef1 suy gi\u1ea3m ch\u1ea5t l\u01b0\u1ee3ng s\u1ebd d\u1ec5 d\u00e0ng d\u1eabn \u0111\u1ebfn c\u00e1c ti\u00eau c\u1ef1c nh\u01b0: t\u0103ng tr\u01b0\u1edfng c\u1ee7a c\u00e1, nguy c\u01a1 xu\u1ea5t hi\u1ec7n b\u1ec7nh (Timmons et al. 2002). T\u1ed1n k\u00e9m chi ph\u00ed v\u1eadn h\u00e0nh v\u00e0 duy tr\u00ec ho\u1ea1t \u0111\u1ed9ng c\u0169ng nh\u01b0 \u0111\u00f2i h\u1ecfi c\u00f4ng nh\u00e2n s\u1ea3n xu\u1ea5t ph\u1ea3i \u0111\u01b0\u1ee3c \u0111\u00e0o t\u1ea1o.<\/p>\n

3. \u1ee8ng d\u1ee5ng c\u00f4ng ngh\u1ec7 Biofloc trong nu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n<\/strong><\/p>\n

3.1. Biofloc l\u00e0 g\u00ec?<\/strong>
\nBiofloc l\u00e0 m\u1ed9t ph\u1ee9c h\u1ee3p (d\u1ea1ng c\u1ee5m k\u1ebft d\u00ednh) bao g\u1ed3m c\u00e1c lo\u00e0i t\u1ea3o, t\u1ea3o bi\u1ec3n l\u1edbn, \u0111\u1ed9ng v\u1eadt nguy\u00ean sinh, m\u1ea3nh v\u1ee5n h\u1eefu c\u01a1, vi khu\u1ea9n. M\u1ed7i h\u1ea1t biofloc \u0111\u01b0\u1ee3c g\u1eafn k\u1ebft l\u1ea1i v\u1edbi nhau b\u1edfi ch\u1ea5t nh\u1eddn \u0111\u01b0\u1ee3c ti\u1ebft ra t\u1eeb vi khu\u1ea9n, ch\u00fang k\u1ebft d\u00ednh v\u1edbi nhau b\u1edfi c\u00e1c vi sinh v\u1eadt d\u1ea1ng s\u1ee3i. H\u1ec7 sinh v\u1eadt tr\u00ean biofloc c\u0169ng bao g\u1ed3m c\u00e1c \u0111\u1ed9ng v\u1eadt ph\u00f9 du v\u00e0 giun tr\u00f2n. Biofloc trong h\u1ec7 th\u1ed1ng n\u01b0\u1edbc xanh th\u01b0\u1eddng c\u00f3 k\u00edch th\u01b0\u1edbc l\u1edbn (50 \u2013 200 \u00b5m), v\u00e0 r\u1ea5t d\u1ec5 l\u1eafng xu\u1ed1ng trong n\u01b0\u1edbc t\u0129nh.<\/p>\n

3.2. Vai tr\u00f2 c\u1ee7a biofloc<\/strong>
\nBiofloc kh\u00f4ng nh\u1eefng c\u00f3 t\u00e1c d\u1ee5ng c\u1ea3i thi\u1ec7n ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc m\u00e0 c\u00f2n l\u00e0 ngu\u1ed3n th\u1ee9c \u0103n gi\u00e0u dinh d\u01b0\u1ee1ng cho t\u00f4m, c\u00e1 nu\u00f4i. C\u00e1c lo\u1ea1i vi khu\u1ea9n trong biofloc (vi khu\u1ea9n d\u1ecb d\u01b0\u1ee1ng) c\u00f3 kh\u1ea3 n\u0103ng chuy\u1ec3n h\u00f3a v\u1eadt ch\u1ea5t h\u1eefu c\u01a1 th\u00e0nh sinh kh\u1ed1i n\u00ean c\u00f3 th\u1ec3 l\u00e0m th\u1ee9c \u0103n cho t\u00f4m, c\u00e1 (Avnimelech, 2012). Biofloc c\u00f3 h\u00e0m l\u01b0\u1ee3ng \u0111\u1ea1m kh\u00e1 cao (25- 50% kh\u1ed1i l\u01b0\u1ee3ng kh\u00f4) v\u00e0 l\u00e0 ngu\u1ed3n vitamin, kho\u00e1ng c\u1ea7n thi\u1ebft cho t\u00f4m c\u00e1, \u0111\u1eb7c bi\u1ec7t l\u00e0 ngu\u1ed3n phospho. Theo Hargreaves (2013), biofloc c\u00f3 m\u1ed9t s\u1ed1 l\u1ee3i \u00edch nh\u01b0:<\/p>\n

– Th\u00fac \u0111\u1ea9y t\u0103ng tr\u01b0\u1edfng c\u1ee7a c\u00e1, t\u00f4m nh\u1edd c\u00e1c th\u00e0nh ph\u1ea7n dinh d\u01b0\u1ee1ng c\u1ee7a n\u00f3.<\/p>\n

– Gia t\u0103ng ch\u1ea5t l\u01b0\u1ee3ng th\u1ecbt t\u00f4m, m\u00e0u s\u1eafc.<\/p>\n

– C\u1ea3i thi\u1ec7n ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc ao nu\u00f4i qua vi\u1ec7c lo\u1ea1i b\u1ecf m\u1ed9t s\u1ed1 \u0111\u1ed9c t\u1ed1 nh\u01b0 amonia, nitrite.<\/p>\n

– Gi\u1ea3m h\u1ec7 s\u1ed1 th\u1ee9c \u0103n FCR.<\/p>\n

– T\u0103ng c\u01b0\u1eddng an to\u00e0n sinh h\u1ecdc.<\/p>\n

3.3. \u1ee8ng d\u1ee5ng c\u00f4ng ngh\u1ec7 biofloc trong nu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n<\/strong><\/p>\n

C\u00f4ng ngh\u1ec7 biofloc \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng trong nu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n nh\u01b0 l\u00e0 m\u1ed9t gi\u1ea3i ph\u00e1p h\u1eefu hi\u1ec7u \u0111\u1ec3 c\u1ea3i thi\u1ec7n m\u00f4i tr\u01b0\u1eddng n\u01b0\u1edbc v\u00e0 l\u00e0 ngu\u1ed3n dinh d\u01b0\u1ee1ng t\u1ed1t cho \u0111\u1ed1i t\u01b0\u1ee3ng nu\u00f4i (De Schryver, et al., 2008; Avnimelech, 2012). Nh\u1eefng \u0111\u00f3ng g\u00f3p v\u1ec1 m\u1eb7t dinh d\u01b0\u1ee1ng c\u1ee7a biofloc trong nu\u00f4i t\u00f4m \u0111\u00e3 \u0111\u01b0\u1ee3c c\u00e1c nh\u00e0 khoa h\u1ecdc nghi\u00ean c\u1ee9u h\u01a1n hai th\u1eadp k\u1ef7 qua. K\u1ebft qu\u1ea3 nghi\u00ean c\u1ee9u c\u1ee7a Burford et al. (2003; 2004) cho th\u1ea5y c\u00f3 kho\u1ea3ng 20 \u2013 30% protein \u0111\u01b0\u1ee3c t\u00f4m h\u1ea5p thu t\u1eeb biofloc. \u1ee8ng d\u1ee5ng c\u00f4ng ngh\u1ec7 biofloc c\u00f2n l\u00e0m t\u0103ng n\u0103ng su\u1ea5t, khi nu\u00f4i t\u00f4m ch\u00e2n tr\u1eafng trong h\u1ec7 th\u1ed1ng Raceway k\u1ebft h\u1ee3p thu t\u1ec9a, n\u0103ng su\u1ea5t c\u00f3 th\u1ec3 \u0111\u1ea1t t\u1edbi 51 t\u1ea5n\/ha (Nyan, 2010). Biofloc c\u0169ng \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng trong nu\u00f4i c\u00e1 r\u00f4 phi (Oreochromis niloticus x Oreochromis aureus), c\u00e1 \u0111\u01b0\u1ee3c nu\u00f4i v\u1edbi th\u1ee9c \u0103n vi\u00ean c\u00f3 30% \u0111\u1ea1m (\u0111\u1ed1i ch\u1ee9ng) v\u00e0 20% \u0111\u1ea1m k\u1ebft h\u1ee3p biofloc, l\u01b0\u1ee3ng th\u1ee9c \u0103n s\u1eed d\u1ee5ng h\u00e0ng ng\u00e0y t\u01b0\u01a1ng \u1ee9ng v\u1edbi 2 lo\u1ea1i th\u1ee9c l\u00e0 2% v\u00e0 2,6% kh\u1ed1i l\u01b0\u1ee3ng th\u00e2n. K\u1ebft qu\u1ea3 cho th\u1ea5y c\u00e1 t\u0103ng tr\u01b0\u1edfng t\u1ed1t h\u01a1n \u1edf nghi\u1ec7m th\u1ee9c biofloc c\u00f9ng v\u1edbi h\u1ec7 s\u1ed1 chuy\u1ec3n h\u00f3a th\u1ee9c \u0103n (FCR) th\u1ea5p v\u00e0 h\u1ec7 s\u1ed1 chuy\u1ec3n h\u00f3a \u0111\u1ea1m (PCR) c\u0169ng gi\u1ea3m \u0111\u00e1ng k\u1ec3. H\u1ec7 s\u1ed1 PCR \u1edf nghi\u1ec7m th\u1ee9c \u0111\u1ed1i ch\u1ee9ng t\u1eeb 4,35 \u0111\u1ebfn 4,38 c\u00f3 ngh\u0129a l\u00e0 ch\u1ec9 23% l\u01b0\u1ee3ng \u0111\u1ea1m t\u1eeb th\u1ee9c \u0103n \u0111\u01b0\u1ee3c chuy\u1ec3n h\u00f3a sang c\u00e1. Trong khi \u0111\u00f3, h\u1ec7 s\u1ed1 PCR \u1edf nghi\u1ec7m th\u1ee9c biofloc ch\u1ec9 trong kho\u1ea3ng 2,2-2,4, c\u00f3 ngh\u0129a l\u00e0 vi\u1ec7c s\u1eed d\u1ee5ng ch\u1ea5t \u0111\u1ea1m cao h\u01a1n g\u1ea7n g\u1ea5p \u0111\u00f4i. Chi ph\u00ed th\u1ee9c \u0103n c\u0169ng gi\u1ea3m t\u1eeb 0,85 USD \u0111\u1ec3 s\u1ea3n xu\u1ea5t ra 1 kg c\u00e1 trong l\u00f4 \u0111\u1ed1i ch\u1ee9ng so v\u1edbi 0,55USD trong nghi\u1ec7m th\u1ee9c biofloc (Avnimelech et al., 1994).<\/p>\n

Biofloc \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng trong nu\u00f4i v\u1ed7 th\u00e0nh th\u1ee5c 3 lo\u00e0i t\u00f4m b\u1ed1 m\u1eb9 l\u00e0 t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng (L. vannamei), t\u00f4m h\u1ed3ng (F. duorarum) v\u00e0 t\u00f4m th\u00e2n xanh (L. stylirostris), k\u1ebft qu\u1ea3 cho th\u1ea5y biofloc c\u00f3 th\u1ec3 c\u1ea3i thi\u1ec7n kh\u1ea3 n\u0103ng sinh s\u1ea3n c\u1ee7a t\u00f4m b\u1ed1 m\u1eb9 so v\u1edbi ph\u01b0\u01a1ng ph\u00e1p nu\u00f4i v\u1ed7 truy\u1ec1n th\u1ed1ng, t\u00f4m \u0111\u1ebb s\u1edbm h\u01a1n v\u1edbi s\u1ed1 l\u01b0\u1ee3ng tr\u1ee9ng tr\u00ean m\u1ed9t l\u1ea7n sinh s\u1ea3n nhi\u1ec1u h\u01a1n (Emerenciano et al., 2011).<\/p>\n

Hari et al. (2006) nghi\u00ean c\u1ee9u \u1ea3nh h\u01b0\u1edfng c\u1ee7a vi\u1ec7c b\u1ed5 sung carbohydrate l\u00ean ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc v\u00e0 s\u1ef1 bi\u1ebfn \u0111\u1ed9ng c\u1ee7a Nitrogen trong ao nu\u00f4i t\u00f4m s\u00fa. K\u1ebft qu\u1ea3 cho th\u1ea5y b\u1ed5 sung carbohydrate l\u00e0m t\u0103ng t\u1ed5ng vi khu\u1ea9n d\u1ecb d\u01b0\u1ee1ng, l\u00e0m gi\u1ea3m h\u00e0m l\u01b0\u1ee3ng TAN, Nitrite trong n\u01b0\u1edbc v\u00e0 h\u00e0m l\u01b0\u1ee3ng TAN trong b\u00f9n \u0111\u00e1y ao nu\u00f4i; \u0111\u1ed3ng th\u1eddi l\u00e0m gi\u1ea3m \u0111\u01b0\u1ee3c nhu c\u1ea7u protein trong th\u1ee9c \u0103n cho t\u00f4m nu\u00f4i. Kuhn et al. (2009), \u0111\u00e3 th\u1ef1c hi\u1ec7n th\u00ed nghi\u1ec7m s\u1eed d\u1ee5ng biofloc thu t\u1eeb ao nu\u00f4i c\u00e1 r\u00f4 phi thay th\u1ebf m\u1ed9t ph\u1ea7n b\u1ed9t c\u00e1 v\u00e0 b\u1ed9t \u0111\u1eadu n\u00e0nh trong kh\u1ea9u ph\u1ea7n \u0103n c\u1ee7a t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng cho th\u1ea5y kh\u00f4ng c\u00f3 s\u1ef1 kh\u00e1c bi\u1ec7t v\u1ec1 t\u1ef7 l\u1ec7 s\u1ed1ng (93\u2013100%) nh\u01b0ng t\u0103ng tr\u01b0\u1edfng c\u1ee7a t\u00f4m nu\u00f4i \u1edf nghi\u1ec7m th\u1ee9c c\u00f3 thay th\u1ebf biofloc t\u1ed1t h\u01a1n. Sau 35 ng\u00e0y nu\u00f4i th\u1eed nghi\u1ec7m, kh\u1ed1i l\u01b0\u1ee3ng trung b\u00ecnh t\u00f4m nu\u00f4i \u1edf c\u00e1c nghi\u1ec7m th\u1ee9c thay th\u1ebf 7,8% v\u00e0 15,6% b\u1ed9t \u0111\u1eadu n\u00e0nh b\u1eb1ng biofloc (t\u00ednh theo v\u1eadt ch\u1ea5t kh\u00f4) l\u1ea7n l\u01b0\u1ee3t l\u00e0 8,18 g v\u00e0 8,07 g; nghi\u1ec7m th\u1ee9c thay th\u1ebf 7,8% b\u1ed9t c\u00e1 b\u1eb1ng biofloc, kh\u1ed1i l\u01b0\u1ee3ng t\u00f4m trung b\u00ecnh l\u00e0 8,13 g; trong khi nghi\u1ec7m th\u1ee9c cho \u0103n b\u1eb1ng b\u1ed9t c\u00e1 v\u00e0 b\u1ed9t \u0111\u1eadu n\u00e0nh ch\u1ec9 \u0111\u1ea1t trung b\u00ecnh 5,46 g v\u00e0 4,42 g.<\/p>\n

V\u1ea5n \u0111\u1ec1 quan tr\u1ecdng trong c\u00f4ng ngh\u1ec7 biofloc l\u00e0 t\u1ea1o \u0111i\u1ec1u ki\u1ec7n t\u1ed1i \u01b0u \u0111\u1ec3 vi sinh v\u1eadt d\u1ecb d\u01b0\u1ee1ng ph\u00e1t tri\u1ec3n, h\u1ea5p th\u1ee5 amonium, t\u1ea1o sinh kh\u1ed1i l\u00e0m th\u1ee9c \u0103n cho v\u1eadt nu\u00f4i. Vi sinh v\u1eadt d\u1ecb d\u01b0\u1ee1ng s\u1eed d\u1ee5ng C h\u1eefu c\u01a1 \u0111\u01b0\u1ee3c b\u1ed5 sung v\u00e0 ngu\u1ed3n N th\u1ea3i ra t\u1eeb th\u1ee9c \u0103n \u0111\u1ec3 t\u1ed5ng h\u1ee3p n\u00ean protein. N\u1ebfu b\u1ed5 sung C v\u1edbi t\u1ef7 l\u1ec7 th\u00edch h\u1ee3p s\u1ebd t\u0103ng c\u01b0\u1eddng qu\u00e1 tr\u00ecnh chuy\u1ec3n h\u00f3a N v\u00f4 c\u01a1 th\u00e0nh protein trong sinh kh\u1ed1i vi sinh v\u1eadt. Theo Widanarni et al. (2010) khi b\u1ed5 sung r\u1ec9 \u0111\u01b0\u1eddng v\u00e0o m\u00f4i tr\u01b0\u1eddng \u01b0\u01a1ng t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng (Litopenaeus vannamei), th\u00ec t\u1ec9 l\u1ec7 C\/N = 10 cho t\u1ed1c \u0111\u1ed9 t\u0103ng tr\u01b0\u1edfng v\u00e0 n\u0103ng su\u1ea5t cao nh\u1ea5t. Carbon h\u1eefu c\u01a1 th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng l\u00e0 c\u00e1c carbohydrate nh\u01b0 tinh b\u1ed9t, r\u1ec9 \u0111\u01b0\u1eddng, c\u00e1m g\u1ea1o, glycerol… ho\u1eb7c b\u1eb1ng c\u00e1ch thay \u0111\u1ed5i th\u00e0nh ph\u1ea7n th\u1ee9c \u0103n: t\u0103ng h\u00e0m l\u01b0\u1ee3ng carbohydrate v\u00e0 gi\u1ea3m protein (T\u1ef7 l\u1ec7 C trong carbohydrate th\u01b0\u1eddng l\u00e0 50%).<\/p>\n

4. C\u00e1c nghi\u00ean c\u1ee9u trong n\u01b0\u1edbc<\/strong><\/p>\n

K\u1ebft qu\u1ea3 \u1ee9ng d\u1ee5ng c\u00f4ng ngh\u1ec7 biofloc trong nu\u00f4i th\u00e2m canh t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng Litopenaeus vannamie \u1edf Vi\u1ec7t Nam c\u0169ng \u0111\u1ea1t m\u1ee5c ti\u00eau m\u1ee5c ti\u00eau gi\u1ea3m \u00f4 nhi\u1ec5m m\u00f4i tr\u01b0\u1eddng, t\u0103ng t\u1ef7 l\u1ec7 s\u1ed1ng, n\u0103ng su\u1ea5t v\u00e0 gi\u1ea3m tr\u00ean 20 % h\u1ec7 s\u1ed1 th\u1ee9c \u0103n c\u1ee7a t\u00f4m (Nguy\u1ec5n Th\u1ecb Thu Hi\u1ec1n v\u00e0 Nguy\u1ec5n V\u0103n Hu\u1ea5n, 2013). K\u1ebft qu\u1ea3 cho th\u1ea5y c\u00e1c ao nu\u00f4i theo c\u00f4ng ngh\u1ec7 biofloc \u1edf H\u1ea3i Ph\u00f2ng c\u00f3 b\u1ed5 sung ngu\u1ed3n cacbon l\u00e0 m\u1eadt r\u1ec9 \u0111\u01b0\u1eddng, t\u1ef7 l\u1ec7 C\/N l\u00e0 12 \u0111\u1ea1t n\u0103ng su\u1ea5t 17,6 t\u1ea5n\/ha\/v\u1ee5 v\u1edbi h\u1ec7 s\u1ed1 th\u1ee9c \u0103n l\u00e0 0,92. T\u01b0\u01a1ng t\u1ef1, trong c\u00e1c ao nu\u00f4i \u1edf B\u1ea1c Li\u00eau n\u0103ng su\u1ea5t \u0111\u1ea1t \u0111\u01b0\u1ee3c 15,9 t\u1ea5n\/ha\/v\u1ee5, v\u00e0 h\u1ec7 s\u1ed1 th\u1ee9c \u0103n l\u00e0 1,03.<\/p>\n

Khoa Th\u1ee7y s\u1ea3n \u2013 Tr\u01b0\u1eddng \u0110\u1ea1i h\u1ecdc C\u1ea7n Th\u01a1 c\u0169ng \u0111\u00e3 c\u00f3 c\u00e1c nghi\u00ean c\u1ee9u \u1ee9ng d\u1ee5ng biofloc trong \u01b0\u01a1ng nu\u00f4i t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng, v\u00e0 nu\u00f4i c\u00e1 r\u00f4 phi. K\u1ebft qu\u1ea3 nghi\u00ean c\u1ee9u c\u1ee7a Ch\u00e2u T\u00e0i T\u1ea3o v\u00e0 ctv. (2015a) \u01b0\u01a1ng t\u00f4m ch\u00e2n tr\u1eafng theo c\u00f4ng ngh\u1ec7 Biofloc \u1edf m\u1eadt \u0111\u1ed9 2.000 con\/m3 cho k\u1ebft qu\u1ea3 t\u0103ng tr\u01b0\u1edfng nhanh nh\u1ea5t (\u0111\u1ea1t chi\u1ec1u d\u00e0i 4,69 mm sau 28 ng\u00e0y). S\u1ef1 h\u00ecnh th\u00e0nh c\u1ee7a biofloc trong ao nu\u00f4i ph\u1ee5 thu\u1ed9c v\u00e0o nhi\u1ec1u y\u1ebfu t\u1ed1, trong \u0111\u00f3 \u0111\u1ed9 s\u00e2u m\u1ef1c n\u01b0\u1edbc ao nu\u00f4i. Ch\u00e2u T\u00e0i T\u1ea3o v\u00e0 ctv (2015b) \u0111\u00e3 th\u00ed nghi\u1ec7m \u01b0\u01a1ng t\u00f4m ch\u00e2n tr\u1eafng theo c\u00f4ng ngh\u1ec7 Biofloc \u1edf c\u00e1c m\u1ee9c n\u01b0\u1edbc kh\u00e1c nhau (40, 60 v\u00e0 80 cm). T\u00f4m gi\u1ed1ng PL12 \u0111\u01b0\u1ee3c nu\u00f4i \u1edf m\u1eadt \u0111\u1ed9 2.000 con\/m3, \u0111\u1ed9 m\u1eb7n 15 \u2030, trong th\u1eddi gian 28 ng\u00e0y; s\u1eed d\u1ee5ng ngu\u1ed3n b\u1ed9t m\u00ec v\u00e0 b\u1ed9t \u0111\u1eadu n\u00e0nh \u0111\u1ec3 t\u1ea1o biofloc v\u1edbi t\u1ec9 l\u1ec7 C\/N >12; k\u1ebft qu\u1ea3 cho th\u1ea5y th\u1ec3 t\u00edch biofloc \u1edf m\u1ee9c n\u01b0\u1edbc 80 cm l\u00e0 cao nh\u1ea5t (12,7 \u00b1 6,2 ml\/L), t\u0103ng tr\u01b0\u1edfng v\u00e0 t\u1ef7 l\u1ec7 s\u1ed1ng c\u1ee7a t\u00f4m t\u1ed1t nh\u1ea5t.<\/p>\n

L\u00ea Qu\u1ed1c Vi\u1ec7t (2015), nghi\u00ean c\u1ee9u nu\u00f4i t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng \u1edf c\u00e1c m\u1eadt \u0111\u1ed9 150, 200, 250 v\u00e0 300 con\/m3 gh\u00e9p v\u1edbi c\u00e1 r\u00f4 phi v\u1edbi m\u1eadt \u0111\u1ed9 4 con\/m3 v\u00e0 k\u1ebft h\u1ee3p v\u1edbi biofloc (C\/N = 15), sau 60 ng\u00e0y nu\u00f4i k\u1ebft qu\u1ea3 t\u00f4m nu\u00f4i \u1edf m\u1eadt \u0111\u1ed9 150 v\u00e0 200 con\/m3 c\u00f3 t\u1ed1c \u0111\u1ed9 t\u0103ng tr\u01b0\u1edfng v\u1ec1 kh\u1ed1i l\u01b0\u1ee3ng nhanh, t\u1ef7 l\u1ec7 s\u1ed1ng cao, FCR th\u1ea5p h\u01a1n c\u00f3 \u00fd ngh\u0129a so v\u1edbi c\u00e1c nghi\u1ec7m th\u1ee9c kh\u00e1c. Tuy nhi\u00ean, n\u0103ng su\u1ea5t thu \u0111\u01b0\u1ee3c \u1edf c\u00e1c m\u1eadt \u0111\u1ed9 nu\u00f4i kh\u00e1c nhau kh\u00e1c bi\u1ec7t kh\u00f4ng c\u00f3 \u00fd ngh\u0129a th\u1ed1ng k\u00ea (p>0,05).<\/p>\n

T\u1ea1 V\u0103n Ph\u01b0\u01a1ng v\u00e0 ctv. (2014) nghi\u00ean c\u1ee9u c\u00e1ch b\u1ed5 sung carbon h\u1eefu c\u01a1, c\u0169ng k\u1ebft lu\u1eadn r\u1eb1ng, vi\u1ec7c b\u1ed5 sung b\u1ed9t g\u1ea1o v\u1edbi t\u1ef7 l\u1ec7 C:N l\u00e0 15:1 sau khi \u0111\u01b0\u1ee3c \u1ee7 48 gi\u1edd s\u1ebd cho k\u1ebft qu\u1ea3 sinh kh\u1ed1i bioflocs, m\u00f4i tr\u01b0\u1eddng n\u01b0\u1edbc v\u00e0 t\u0103ng tr\u01b0\u1edfng t\u00f4m nu\u00f4i t\u1ed1t nh\u1ea5t.<\/p>\n

T\u00e0i li\u1ec7u tham kh\u1ea3o<\/strong><\/p>\n

Avnimelech, Y, 2012. Bio-floc Technology-A Practical Guide Book, 2nd Edition. The World Aquaculture Society, Baton Rouge, Louisiana, United States. 173 pp.<\/p>\n

Avnimelech, Y., Kochva, M., Diab, S., 1994. Development of controlled intensive aquaculture systems with a limited water exchange and adjusted carbon to nitrogen ratio. Israel J. Aquaculture Bamidgeh 46 (3), 119\u2013131.<\/p>\n

Bergheim, A., A. Drengstig, Y. Ulgenes, and S. Fivelstad, 2008. Dominating Systems for Production of Atlantic Salmon Smolt in Europe. Proceedings of the Aquacultural Engineering Society\u2019s Fourth Issues Forum. 59-72.<\/p>\n

Ch\u00e2u T\u00e0i T\u1ea3o, H\u1ed3 Ng\u1ecdc Ng\u00e0, Tr\u1ea7n Ng\u1ecdc H\u1ea3i. 2015a. \u1ea2nh h\u01b0\u1edfng c\u1ee7a m\u1eadt \u0111\u1ed9 l\u00ean t\u0103ng tr\u01b0\u1edfng v\u00e0 t\u1ef7 l\u1ec7 s\u1ed1ng c\u1ee7a t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng (Litopenaeus vannamei) \u01b0\u01a1ng gi\u1ed1ng theo c\u00f4ng ngh\u1ec7 biofloc, T\u1ea1p ch\u00ed khoa h\u1ecdc, \u0110\u1ea1i h\u1ecdc C\u1ea7n Th\u01a1.<\/p>\n

Ch\u00e2u T\u00e0i T\u1ea3o, L\u00fd Minh trung, Tr\u1ea7n Ng\u1ecdc H\u1ea3i. 2015b. Nghi\u00ean c\u1ee9u \u01b0\u01a1ng gi\u1ed1ng t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng (Litopenaeus vannamei) \u1edf c\u00e1c m\u1ee9c n\u01b0\u1edbc kh\u00e1c nhau theo c\u00f4ng ngh\u1ec7 biofloc, T\u1ea1p ch\u00ed khoa h\u1ecdc, \u0110\u1ea1i h\u1ecdc C\u1ea7n Th\u01a1.<\/p>\n

De Schryver, P., R. Crab, T. Defroit, N. Boon, and W. Verstraete. 2008. The basic of bio-flocs technology: The added value for aquaculture. Aquaculture 277, 125- 137.<\/p>\n

Del Campo, L.M., P. Ibarra, X. Guti\u00e9rrez, H. Takle, 2010. Utilization of sludge from Recirculation aquaculture systems. Nofina report 9\/2010. 73pp.<\/p>\n

Emerenciano Maur\u00edcio, Gerard Cuzon, Korynthia L\u00f3pez Aguiar, Elsa Nore\u00f1aBarroso, Maite M\u00e1scaro and Gabriela Gaxiola, 2011. Bio-floc meal pellet and plant-based diet As AN alternative nutrition for shrimp under limited water exchange system. World Aquaculture 2011.Metcalf and Eddy, 2003. Wastewater Engineering: Treatment and Reuse, 4th edition.<\/p>\n

Hari, B., Madhusoodana Kurup, B., Varghese, J.T., Schrama, J.W., Verdegem, M.C.J., 2006. The effect of carbohydrate addition on water quality and the nitrogen budget in extensive shrimp culture systems. Aquaculture 252 (2\u20134), 248\u2013 263.<\/p>\n

Hochheimer, J. N and F. Wheaton, 1998. Biological filters: Trickling and RBC design. The second international conference on recirculating aquacultrure (pages 291-317).<\/p>\n

Kristensen, T., \u00c5. \u00c5tland, T. Rosten, H. A. Urke, B.O. Rosseland, 2009. Important influentwater quality parameters at freshwater production systems in two salmon producing countries. Aquacult. Eng. 41, 53-59.<\/p>\n

L\u00ea Qu\u1ed1c Vi\u1ec7t, Tr\u1ea7n Ng\u1ecdc H\u1ea3i, L\u00fd V\u0103n Kh\u00e1nh, Tr\u1ea7n Minh Nh\u1ee9t, T\u1ea1 V\u0103n Ph\u01b0\u01a1ng, 2015. \u1ee8ng d\u1ee5ng biofloc nu\u00f4i t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng (Litopenaeus vannamei) v\u1edbi m\u1eadt \u0111\u1ed9 kh\u00e1c nhau k\u1ebft h\u1ee3p v\u1edbi c\u00e1 r\u00f4 phi (Oreochromis niloticus). T\u1ea1p ch\u00ed khoa h\u1ecdc \u0110\u1ea1i h\u1ecdc C\u1ea7n Th\u01a1, S\u1ed1 38(2015): 44-52<\/p>\n

Losordo, T.M., M.P. Masser, and J. Rakocy, 1999. Recirculating Aquaculture Tank Production Systems: A Review of Component Options. SRAC Publication No. 453, 12p.<\/p>\n

Martins C.I.M. , E.H. Eding, M.C.J. Verdegema, L.T.N. Heinsbroeka, O. Schneiderc, J.P. Blanchetond , E. Roque d\u2019Orbcasteld and J.A.J. Verretha, 2010. New developments in recirculating aquaculture systems in Europe: A perspective on environmental sustainability. Aquacultural Engineering November 2010, Volume 43, Issue 3, Pages 83-93.<\/p>\n

Martins, C.I.M., E.H. Eding, O. Schneider, R. Rasmussen, B. Olesen, L. Plesner, J.A.J. Verreth, 2005. Recirculation Aquaculture Systems in Europe. CONSENSUS. Oostende, Belgium, Consensus working Group, European Aquaculture Society: 31.<\/p>\n

Nyan, 2010. Biofloc Technology Expanding At White Shrimp Farms. Biofloc Systems Deliver High Productivity With Sustainability. Global Aquaculture T3-9, KPMG Tower, 8 First Avenue Persiaran Bandar Utama, 47800, Petaling Jaya, Selangor, Malaysia.<\/p>\n

Nguy\u1ec5n Thanh Ph\u01b0\u01a1ng, Tr\u1ea7n Ng\u1ecdc H\u1ea3i, Tr\u1ea7n Th\u1ecb Thanh Hi\u1ec1n Marcy N. Wilder, 2003. Nguy\u00ean l\u00fd v\u00e0 k\u1ef9 thu\u1eadt s\u1ea3n xu\u1ea5t gi\u1ed1ng t\u00f4m c\u00e0ng xanh (Macrobrachium rosenbergii). Nh\u00e0 xu\u1ea5t b\u1ea3n N\u00f4ng nghi\u1ec7p, 127 trang<\/p>\n

Nguy\u1ec5n Th\u1ecb Thu Hi\u1ec1n, Nguy\u1ec5n V\u0103n Hu\u1ea5n, 2013. Nghi\u00ean c\u1ee9u \u1ee9ng d\u1ee5ng c\u00f4ng ngh\u1ec7 biofloc trong nu\u00f4i th\u00e2m canh t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng (Litopenaeus vannamei) qui m\u00f4 s\u1ea3n xu\u1ea5t. B\u1ea3n tin s\u1ed1 9\/2013. Vi\u1ec7n Nghi\u00ean C\u1ee9u Nu\u00f4i Tr\u1ed3ng Th\u1ee7y s\u1ea3n I.<\/p>\n

Ph\u1ea1m Th\u1ecb Tuy\u1ebft Ng\u00e2n, T\u00f4 C\u00f4ng T\u00e2m, Tr\u01b0\u01a1ng Qu\u1ed1c Ph\u00fa, 2008. \u1ea2nh h\u01b0\u1edfng c\u1ee7a b\u1ed5 sung d\u1ea7u th\u1ef1c v\u1eadt l\u00ean s\u1ef1 \u0111a d\u1ea1ng qu\u1ea7n th\u1ec3 vi sinh v\u1eadt trong b\u1ec3 l\u1ecdc sinh h\u1ecdc. T\u1ea1p ch\u00ed khoa h\u1ecdc, \u0110\u1ea1i h\u1ecdc C\u1ea7n Th\u01a1, 2008 (1): T33-34.<\/p>\n

Sanni, S. and O.I. Forsberg, 1996. Modelling pH and carbon dioxide in single-pass seawater aquaculture systems.Aquacultural Engineering 15(2): 91 \u2013 110.<\/p>\n

T\u1ea1 V\u0103n Ph\u01b0\u01a1ng, Nguy\u1ec5n V\u0103n B\u00e1, Nguy\u1ec5n V\u0103n H\u00f2a (2014). \u1ea2nh h\u01b0\u1edfng c\u1ee7a th\u1eddi gian th\u1ee7y ph\u00e2n v\u00e0 ph\u01b0\u01a1ng th\u1ee9c b\u1ed5 sung b\u1ed9t g\u1ea1o l\u00ean n\u0103ng su\u1ea5t t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng. T\u1ea1p ch\u00ed khoa h\u1ecdc \u0110HCT, S\u1ed1 chuy\u00ean \u0111\u1ec1 Th\u1ee7y s\u1ea3n 2014, t\u1eadp 2. Trang 54-62.<\/p>\n

Terjesen, B. F., Y. Ulgenes, S.O. F\u00e6ra, S.T. Summerfelt, P. Brunsvik, G. Baeverfjord, S. Nerland, H. Takle, O. C. Norvik, , A. Kittelsen, 2008. RAS research facility dimensioning and design: a special case compared to planning production systems. In Aquaculture Engineering Society Issues Forum Proceedings. Roanoke, Virginia, 23rd-24th July, 223-238.<\/p>\n

Timmons, M.B., J.M. Ebling, F.W. Wheaton, S.T. Summerfelt and B.J. Vinci (2002). Recirculating Aquaculture Systems 2nd Edition. Northern Regional Aquaculture Center Publication No. 01 I002. Cayuga Aqua Ventures Ithaca, New York.<\/p>\n

Widanarni, Deby Yuniasari, Sukenda, Julie Ekasari, 2010. Nursery Culture Performance of Litopenaeus vannamei with Probiotics Addition and Different C\/N Ratio Under Laboratory Condition. HAYATI Journal of Biosciences September 2010 Vol. 17 No. 3, p 115-11.<\/p>\n

[1]Ph\u1ea1m Thanh Li\u00eam, 1,2 Cao v\u0103n Th\u00edch, 1Ch\u00e2u T\u00e0i T\u1ea3o & 1Tr\u1ea7n Ng\u1ecdc H\u1ea3i<\/em><\/p>\n

Khoa Th\u1ee7y s\u1ea3n \u2013 Tr\u01b0\u1eddng \u0110\u1ea1i h\u1ecdc C\u1ea7n Th\u01a1<\/em><\/p>\n

1: Tr\u01b0\u1eddng \u0110\u1ea1i h\u1ecdc C\u1ea7n Th\u01a1, 2: Tr\u01b0\u1eddng Trung c\u1ea5p Kinh t\u1ebf – K\u1ef9 thu\u1eadt An Giang<\/em><\/p>\n

Khoa Th\u1ee7y s\u1ea3n \u2013 Tr\u01b0\u1eddng \u0110\u1ea1i h\u1ecdc C\u1ea7n Th\u01a1<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

\u0110\u1ec3 x\u00e2y d\u1ef1ng c\u00e1c m\u00f4 h\u00ecnh nu\u00f4i ph\u00e1t tri\u1ec3n b\u1ec1n v\u1eefng, th\u00e2n thi\u1ec7n v\u1edbi m\u00f4i tr\u01b0\u1eddng, xu h\u01b0\u1edbng hi\u1ec7n nay l\u00e0 \u0111\u1ea9y m\u1ea1nh vi\u1ec7c \u00e1p d\u1ee5ng c\u00e1c bi\u1ec7n ph\u00e1p k\u1ef9 thu\u1eadt v\u00e0 sinh h\u1ecdc t\u00e1c \u0111\u1ed9ng nh\u1eb1m l\u00e0m t\u0103ng hi\u1ec7u qu\u1ea3 s\u1eed d\u1ee5ng ngu\u1ed3n t\u00e0i nguy\u00ean n\u01b0\u1edbc th\u00f4ng qua vi\u1ec7c qu\u1ea3n l\u00fd ch\u1ea5t l\u01b0\u1ee3ng n\u01b0\u1edbc […]<\/p>\n","protected":false},"author":17,"featured_media":5073,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[47],"tags":[],"class_list":["post-4590","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-tin-tuc"],"_links":{"self":[{"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/posts\/4590","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/users\/17"}],"replies":[{"embeddable":true,"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/comments?post=4590"}],"version-history":[{"count":2,"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/posts\/4590\/revisions"}],"predecessor-version":[{"id":5074,"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/posts\/4590\/revisions\/5074"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/media\/5073"}],"wp:attachment":[{"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/media?parent=4590"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/categories?post=4590"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/casta.ttud.com.vn\/index.php\/wp-json\/wp\/v2\/tags?post=4590"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}