Harsashiwata hanyar haɗi ce ta zama dole don haɓakar crustaceans.Penaeus vannamei yana buƙatar yayyafa sau da yawa a rayuwarsa don saduwa da ma'auni na girman jiki.

Ⅰ, Rushe dokokin Penaeus vannamei

Jikin Penaeus vannamei dole ne ya rushe lokaci-lokaci don cimma manufar girma.Lokacin da yawan zafin jiki na ruwa ya kai 28 ℃, matasan shrimps suna raguwa sau ɗaya a cikin 30 ~ 40 hours;Matasa shrimps masu nauyin 1 ~ 5g suna raguwa sau ɗaya a cikin kwanaki 4-6;Pirawns sama da 15g gabaɗaya yana raguwa sau ɗaya kowane mako 2.

Ⅱ、 Nazarin alamomi da yawa da kuma dalilan molting

1. Alamomi da dama na molting period

Harsashin shrimp yana da wuyar gaske, wanda akafi sani da "ron fata shrimp".Yana da komai a ciki ko ragowar ciki.Ba zai iya ganin fili na hanji a fili ba, pigment a jikin jiki yana zurfafa, kuma launin rawaya yana karuwa sosai.Musamman bangarorin biyu na operculum baki ne, ja da rawaya, filayen gill sun kumbura, farare, rawaya da baki, sannan matakai da kafafu suna rufe da jajayen tabo.Shaci na hepatopancreas a bayyane yake, ba kumbura ko atrophic ba, kuma jigon yankin zuciyar ba shi da tabbas kuma rawaya mai laka.

2. Shrimp yawanci yana da ciliates da yawa

Harsashi na shrimp fata ne mai nau'i biyu, wanda za'a iya cire shi ta hanyar karkatar da fata a hankali.Fatar tana da rauni sosai, wanda akafi sani da "kayan fata guda biyu" ko "Crispy Shrimp".Yana da bakin ciki, tare da ƙarin melanin a saman jiki, kumburi da ulceration na gill filaments, yawanci rawaya da baki.Hanji mara komai da ciki, raunin kuzari.Kwanciya a gefen tafkin ko yawo akan ruwa, yana nuna alamun hypoxia.Mai hankali ga sauye-sauyen muhalli, tare da ƴan canje-canje da ƙaruwar mace-mace.

3. Tsarin molting mai santsi za a iya raba kusan zuwa matakai uku masu zuwa:

1) Kafin molting, yana nufin lokacin daga ƙarshen molting na ƙarshe zuwa farkon molting na gaba.Lokacin ya bambanta bisa ga tsawon jiki, gabaɗaya tsakanin kwanaki 12 zuwa 15.A wannan lokacin, Penaeus vannamei ya fi tara abinci mai gina jiki, musamman ma calcium.

2) Molting, kawai 'yan daƙiƙa zuwa fiye da minti goma.Molting yana cinye makamashi mai yawa.Idan jatan lande ba su da rauni ko rashin wadataccen abinci mai gina jiki a cikin jiki, sau da yawa suna raguwa da rashin cikawa kuma suna samar da harsashi mai Layer biyu.

3) Bayan molting, yana nufin lokacin da sabuwar fata ta canza daga laushi zuwa tauri, kuma lokacin yana kusan kwanaki 2 ~ 1.5 (sai dai shrimp seedlings).Bayan an kashe tsohon harsashi, sabon harsashi ba zai iya ƙididdigewa a cikin lokaci ba, don haka ya zama "shrimp harsashi mai laushi".

4. Tabarbarewar ingancin ruwa da rashin abinci mai gina jiki sune manyan abubuwan da ke haddasa cutar

Lalacewar ingancin ruwa sau da yawa yana faruwa a cikin tafkunan da ke da launi mai kauri sosai, kuma gaskiyar ta kusan sifili.Akwai fina-finan mai da matattun algae a saman ruwa, wani lokacin kuma akwai fashewar kamshin kifi a saman ruwan.A wannan lokacin, algae suna ninka da yawa, kuma iskar oxygen da aka narkar da a kan ruwa yana da yawa a cikin rana;Da dare, yawan adadin algae ya zama abin da ke cinye iskar oxygen, wanda ke haifar da ƙananan narkar da iskar oxygen a kasan tafkin, wanda ke shafar ciyar da shrimp da molting.Na dogon lokaci, harsashi yana da wuyar gaske.

5. Sauye-sauyen yanayi da dafin da ba a iya gani ba na iya haifar da molting na jatan lande, wanda kuma shine dalilin samuwar "jatan fata guda biyu" da "jaman harsashi mai laushi".

Ⅲ, Muhimmancinkarin sinadarin calciuma lokacin molting na Penaeus vannamei:

Calcium da aka adana a jikin jatan lande ya yi hasara sosai.Idan duniyar waje ba ta daɗaɗawa cikin lokaci, Penaeus vannamei ba zai iya ɗaukar calcium ɗin da ruwa ke bayarwa ba, wanda ke da sauƙin haifar da gazawar molting shrimp.Lokaci mai wuyar harsashi bayan molting yayi tsayi da yawa.Idan kwayoyin cuta ne suka kai masa hari ko kuma sun damu a wannan lokacin, yana da matukar sauki a mutu a cikin batches.Don haka, ya kamata mu kara yawan sinadarin calcium a cikin ruwa ta hanyar wucin gadi.Shrimp na iya sha alli da kuzari a cikin ruwa ta hanyar numfashi da shigar jiki.

Potassium diformate +calcium propionatedon taimakawa hana haifuwar ruwa da kari na calcium ba zai iya taimakawa penaeus vannamei kawai don molt ba, amma kuma yana hana ƙwayoyin cuta da tsayayya da damuwa, don haka inganta fa'idodin noman jatan lande.