READY [of] NAUPLII ARTEMIA PRAWN.
Requirement of Artemia as food live to prawn larva pasca represent conditions which is [is] absolute to be provided, because till now domicile Artemia not yet earned to be replaced with is other. reserved for [by] Cyst [is] the food require to be incubated beforehand. As for quality of hatch of cyst can be seen from various assessment, that is :
- Hatching Efficiency ( HE) that is to the number of nauplii hatching from 1 gram of cyst Artemia
- Hatching Percentage ( H %) [is] the amount of nauplii hatching to be compared to the amount of used cyst
- T0 : needed Incubation period happened hatch of first nauplii
- T90 : needed Incubation period till reach 90 % hatch.
Requirement of Artemia as food live to prawn larva pasca represent conditions which is [is] absolute to be provided, because till now domicile Artemia not yet earned to be replaced with is other. reserved for [by] Cyst [is] the food require to be incubated beforehand. As for quality of hatch of cyst can be seen from various assessment, that is :
- Hatching Efficiency ( HE) that is to the number of nauplii hatching from 1 gram of cyst Artemia
- Hatching Percentage ( H %) [is] the amount of nauplii hatching to be compared to the amount of used cyst
- T0 : needed Incubation period happened hatch of first nauplii
- T90 : needed Incubation period till reach 90 % hatch.
In practice, ready [of] food live Artemia have to [pass/through] process of dekapsulasi beforehand, because will be obtained [by] some advantage, that is
- Needn'T the existence of dissociation of nauplius from covering, because cyst chorion have been eliminated
- content of Energi higher because [do] not wear for the process of hatch
- Cyst have been sterilized from pest [pass/through] condensation of hipokhlorit
- Earn used direct for the food of larva
- lessening the amount of labour.
As for procedure stages;steps of dekapsulasi shall be as follows
1. hydration of Cyst
2. Treatment in condensation of hipokhlorit
3. Wash and activation of residu khiorin
4. Can be used directly as food or dehydrationed to [be] is depository.
Hydrasi Cyst. Omission of coat of khorion perfect can only be [done/conducted] [by] if globular cyst. To get that situation, cyst have to be let puffy by hydration. Generally full (of) hydration can reach [by] after 1 - 2 [hour/clock] with sea water or freshwater ( maximal 35 permil) [at] temperature 25°C.
Treatment in Condensation of Hipokhlorit. For the treatment of dekapsulasi, can be used [by] condensation of Naocl or of Ca ( OCL)2 which more knowledgeable with kaporit. If used Naoci, hence Natrium and of OCL ionized in condensation and formed [by] HOCL in water, while if Ca ( used OCL)2 will be yielded [by] 2 ion of OCL to each;every molecule of hipokhlorit. Can be said that [by] OCL play a part in khorion, but this matter still is not sure. Activity and maximal concentration [is] [at] PH 10, compared to [at] low PH. 0,5 materials gram of aktifdan 14 condensation ml of dekapsulasi needed to dekapsulasi 1 gram of cyst.
[In] many state, Ca ( OCL)2, cheaper as source of active khiorin from [at] Na Ocl2 Ca ( OCL)2 represent more stable product than Na OCL and can be kept longer during. Activity of Ca ( OCL)2 usually precisely [is] such as those which expressed in lable of commercial product ( generally 70 % active materials). Condensation activity of Na OCL can be determined with measuring index of refraktif [at] refraktometer. Its value [is] :
Y = 3000 X - 4003
Y = Activity of Na OCL in gram per litre
X = Make an index to refraktif.
With NaOCl, 0, 15 gram of NaOH technical ( 0,33 ml, 40 % condensation) have to be enhanced in every gram of cyst to increase pH condensation of dekapsulasi until [about/around] 10. If which [is] used [by] Ca(OCl)2 hence 0,67 gram of Na2CO3 or 0,4 gram of CaO have to be made with water go out to sea 35 permil. For Ca(OCl)2, the used [is] its just dilution, by mixing [him/ it] with sea water, volume have been determined and strong diaerasi during [about/around] 10 minute. Hereinafter aerasi killed and suspensi let to tuang and also pregnant dilution [of] condensation of Ca ( OCL)2, can be used for dekapsulasi.
After evacuation of cyst in condensation of dekapsulasi, hence have to be defended in a state of suspensi with aerasi continually. In a few minute take its rise reaction of exothermic oxidation and grow spume. In line with is dissolve [of] him of khorion, happened change of colour of cyst, that is from deep brown to is grey, later;then orange. During dekapsulasi, temperature have to be checked regularly and ice have to be enhanced to prevent the make-up of temperature above 40°C. If cyst defended in condensation of dekapsulasi, will kill embryo. Therefore, cyst have to be removed immediately from condensation after process finish. Solving of process can be [done/conducted] with perception periodical after existence of change of colour of cyst which [is] didekapsulasi.
Wash and Activation of Residu Khiorin. During treatment, condensation of dekapsulasi respond to cyst khorion. Effect of reaction, formed [by] some compound of organokhiorin coherent [at] cyst result of dekapsulasi able to lessen quality and usefulness of cyst which [is] didekapsulasi. Therefore, after wash can be enhanced [by] 1 % Na2S203, counted 0,5 ml / gram of cyst so that form dissolve compound with compound of organokhlorin. Thereby can eliminate condensation pickings of dekapsulasi [at] cyst.
4. Direct Usage [of] Cyst or Dehydration to [be] is Depository.
Cyst result of dekapsulasi can be given direct to predator if needed. This Cyst can be kept for a few day in refrigerator [at] temperature 0 - 4°C. Because can immerse in sea water and also freshwater, hence time used direct as food of predator, needed [by] and aerasi of sirkulasi last for maintaining cyst in suspensi. To [be] is depository [of] cyst result of dekapsulasi, dehydration hams [done/conducted] [by] after finishing activation procedure and wash. For that, cyst have to be defended in saturated condensation [of] Nad (± 330 gram / litre). After [about/around] 3 [hour/clock], salt condensation have to pinch hit for to streamline to dehydration. If dehydrationed, dekapsulasi cyst will become like seed copy and sink although in saturated salt condensation.
Dekapsulasi Cyst which [is] this hydration [of] leak have to and by using filter 120 micron, carried over in place of plastic, enhanced [by] salt condensation and kept in or refrigerator of freezer. Depository [of] dekapsulasi cyst in salt condensation have limitation. During 6 kalends after dekapsulasi, cyst admit of to maintain maximal hatching energy [of] him, ika sekalipunj kept [at] temperature 20°C.Untukperiode longer, continuity of life of cyst downhill seems.
Degradation of energy hatch dekapsulasi cyst which [is] kept in salt condensation possible because of content of aimya which high relative ( [about/around] 20 %). Depository for time old ones from dry dekapsulasi cyst ( content irrigate below/under 5%) enabling if kept in a state of running dry in free media [of] oxygen ( place of filled [by] nitrogen or is air-less).
Source : Ir. Sri Umiyati Sumeru
Dra. Suzy Anna
