Transport rekord?

Almen snak om rejer - Alt andet
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d9ha
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Transport rekord?

Post by d9ha »

Vil lige dele en oplevelse:

Solgte nogen rejer til an nordmand i juni og afsendte 25 stk. neocaridina i to poser den 19 juni til adressen i Sydnorge. Af ukendte årsager, var rejerne endnu ikke nået frem den 30 juni, hvor modtageren tog på ferie.
Jeg fik så en tilbagemelding i går, at han var retur fra ferie og havde afhentet pakken (20 Juli). Ud af de 25 var der 2 døde.
Synes jeg er ret imponerende at de kan klare sig en hel måned pakket i alm. fiskepose med vand og luft.


Mvh
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Aquahorti
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Re: Transport rekord?

Post by Aquahorti »

Man må næsten antage at de går i en form for dvaletilstand for at kunne klare den bedrift.

OK fik gravet denne artikel op på Researchgate og hvis man skal bruge deres resultater vil der være en overdødelighed blandt rejerne.

http://journals.plos.org/plosone/articl ... =printable

efter 28 dages faste ser de ca. 70% dødelighed. Det at de har haft et par døde venner de har kunne spise kan sikkert hjælpe, men det ser i henhold til denne artikel ikke specielt godt ud for den fremtidige overlevelsesrate.



d9ha
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Re: Transport rekord?

Post by d9ha »

Nu har jeg kun skimmet artiklen, men for mig lyder det som om de regenerer langsomt når de igen får adgang til foder. Der var også lidt hornblad til at sidde på i posen, så de har heller ikke været helt uden føde. Men forklaringen er nok, at de er gået lidt ned i kadence i mørket.


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Re: Transport rekord?

Post by Aquahorti »

Ikke helt:

Results
Point of No-Return (PNR50)—Regeneration. The point of no-return (PNR50) was equal to 24.72 ±0.08. For the shrimp that were starved continuously for 14 days, the regeneration period was equal to three days, while for the shrimp that were starved for 21 days (close to the PNR50), the regeneration period was extended to seven days but was still possible (Fig 1A). No differences were observed between males and females, and therefore the description concerns both sexes. Additionally, the description is connected with the B- and F-cells in the hepatopan- creas (Fig 1B) and D-cells in the intestine (Fig 1C) because no changes were observed in the E- cells of either organ.

og hvis man kigger på grafen kan se mortalitetsraten.

Metoden de brugte kan minde noget om transport af rejer, vandskiftene trækker i den ene retning, medens fjernelsen af eksoskeletter og fæces trækker i den anden retning:

Materials
The research was conducted on adult males and females of the freshwater shrimp Neocaridina davidi (previously called N. heteropoda) (Crustacea, Malacostraca, Decapoda). The specimens were obtained from local shrimp breeders and kept in a main laboratory breed, i.e. 40 L shrimp tank equipped with a heater with a thermostat and a mechanical filtration system. The water temperature was set to 21 ̊C, pH to 7 and total water hardness was equal to 100d. The N. davidi shrimp were fed with JBL Novo Prawn.
Experiment. The starvation experiment was performed by placing the shrimp in isolated plastic (250 mL) containers. For the experiment, adult shrimp with a cephalothorax length above 2.5 mm were chosen. Every day 10% of the water was replaced and the plastic containers were cleared of excrements and cuticle exoskeletons. Containers were kept in a shaded room to avoid the development of algae. The shrimp were starved for 7, 14 and 21 days. Specimens from each experimental group were collected for the studies. Additionally, some specimens from each experimental group were re-fed for 4, 7, 14 and 21 days. The number of specimens from each experimental group that were collected for the experiment and all of the techniques that were used is presented in Table 2.



kim m
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Re: Transport rekord?

Post by kim m »

Ja det er lidt tricky at sende til Norge. Jeg har haft et par transporter mellem 11 og 14 dage som gik fint. De fleste ganger tager det heldigvis kun 4-5 dage.


Besøg min blog: easyshrimp.blogspot.dk

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Aquahorti
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Re: Transport rekord?

Post by Aquahorti »

Kom i tanke om at denne artikel kunne have interesse også selv om det ikke er ofte man sender meget unge rejer.

https://www.researchgate.net/publicatio ... ea_Atyidae



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