... years through the development anduseof a succession of live food organisms as feed for the developing larvae The aim ofthe present manual was therefore to review and summarise the latest developments ... permission ofthe copyright owner Applications for such permission, with a statement ofthe purpose and extent ofthe reproduction, should be addressed to the Director, Information Division, Food and ... concerning the production anduseofthe major live food organisms currently employed in larviculture worldwide This document has been prepared within the framework ofthe aquaculture nutrition and...
... the advantage of allowing control ofthe quality ofthe cultures The major difficulty in microscopic counts is reproducibility, which is a function ofthe sampling, diluting, and filling ofthe ... between the culture medium andthe air The latter is of primary importance as the air contains the carbon source for photosynthesis in the form of carbon dioxide For very dense cultures, the CO2 ... extensive research efforts, theuseof artificial diets in the culture of bivalve molluscs is still very limited The advantages and disadvantages of each ofthe three classes of replacement diets for...
... area The growth ofthe animal is assured by plasma increase and not by cell division The epidermis contains a densely packed layer of keratin-like proteins and is called the lorica The shape ofthe ... the lorica The shape ofthe lorica andthe profile ofthe spines and ornaments allow the determination ofthe different species and morphotypes (see 3.4.) The rotifers body is differentiated ... consisting ofthe head, trunk and foot (Fig 3.1.) The head carries the rotatory organ or corona which is easily recognized by its annular ciliation and which is at the origin ofthe name ofthe Rotatoria...
... to feet and feathers of birds, and when ingested they remain intact for at least a couple of days in the digestive tract of birds Consequently the absence of migrating birds is probably the reason ... salinity is the common feature determining the presence of Artemia, the impact of other parameters (temperature, primary food production, etc.) may at most affect the abundance ofthe population and ... expansion of aquaculture production in the 1970’s, the demand for Artemia cysts soon exceeded the offer and prices rose exponentially, turning Artemia into a bottleneck for the expansion ofthe hatchery...
... weeks, theuseof decapsulated cysts constitutes a saving of over one third in the amount of Artemia cysts used, compared to theuseof live nauplii Table 4.2.4 The proximate composition (in % of ... and hatchability Hatchability of cysts is largely determined by the conditions and techniques applied for harvesting, cleaning, drying and storing ofthe cyst material The impact of most of these ... release over 80% of their cellular water, and upon interruption ofthe aeration, the now coffeebean shaped decapsulated cysts settle out After harvesting of these cysts on a mesh screen they should...
... 1986) On the other hand, instar II stages may be more susceptible to digestive enzyme breakdown in the gut ofthe predator since these enzymes can also penetrate the digestive tract ofthe Artemia ... generally used for feeding the late larval and postlarval stages of penaeids Freshly-hatched nauplii are usually offered at the start ofthe first mysis stage, and sometimes even earlier at the zoea-mysis ... and swallow their prey in one bite the size ofthe nauplii is particularly critical For example, fish larvae that are offered oversized Artemia nauplii may starve because they cannot ingest the...
... influence the feeding behavior of Artemia by affecting the filtration rate, ingestion rate and/ or assimilation: including the quality and quantity ofthe food offered, the developmental stage ofthe ... (1992) The system does not require theuseof feeding pumps and involves minimal care The pilot system consists of six oval raceway tanks of m3 (see above) and six reservoir tanks ofthe same ... down the DHA as is the case in nauplii There is however, an alternative method that takes profit ofthe specific aspects of ongrown Artemia: instead of adding the enrichment emulsion at the end of...
... the acidity ofthe bottom Theuseof organic fertilizers increases the risk of infections This risk can be reduced by composting the manure before use One ofthe main disadvantages of organic ... to the effect of diapause or simply to the viability ofthe embryo The most common diapause deactivating methods used are described in chapter 4.2.1.4 However, before implementing any of these ... (degradation of organic matter by bacteria) andthe nutrient level in the intake water, nitrogen often limits algae growth Theuseof nitrogen fertilizers is therefore widespread Four types of inorganic...
... effective and rapid the filtration Hence, the upper limit ofthe dimensions ofthe nets depends on the ease of handling rather than anything else The effectiveness of filtering is also influenced by the ... filtration and prevent losses due to the narrow and strong back current The longer the distance between the propeller andthe net, the wider and shorter the net can be The distance between the propeller ... gates The amount of zooplankton collected depends on the zooplankton concentration in the water flowing out ofthe reservoir and on the volume ofthe water leaving the reservoir Again, the nets...
... the animals have migrated to the top ofthe tube, where they can be collected with theuseof a pipet onto a 100 µm mesh screen After rinsing with seawater, the nematodes can then be fed to the ... particles from the water The efficiency ofthe filter allows even the uptake of bacteria (approx 1µm) In a study on the food quality of freshwater phytoplankton for the production of cladocerans, ... in the broodpouch andthe larvae are miniature versions ofthe adults In some cases the embryonic period does not correspond with the brood period, and this means that the larvae are held in the...
... information and education to the public and to users about the environmental consequences ofthe choice of particular activities and products, their useand ultimate disposal; (b) The development and ... subject-matter ofthe dispute 14 Unless the arbitral tribunal determines otherwise because ofthe particular circumstances ofthe case, the expenses ofthe tribunal, including the remuneration of its ... two months ofthe appointment ofthe second arbitrator, the Executive Secretary ofthe Economic Commission for Europe shall, at the request of either party to the dispute, designate the president...
... tie the upper set at the back of your head andthe lower set at the base of your neck If a mask has elastic head bands, separate the two bands, hold the mask in one hand andthe bands in the other ... one hand under the cuff ofthe opposite arm Pull the hand into the sleeve, grasping the gown from inside Reach across and push the sleeve off the opposite arm Fold the gown towards the inside and ... Place and hold the mask over your nose, mouth, and chin, then stretch the bands over your head and secure them comfortably as shown; one band on the upper back of your head, the other below the...
... previously used to identify new herpesviruses are discussed andthe latest refined assays and their utility are provided Theuseofthe CODEHOP methodology for the analysis of larger regions of viral ... genomes Often the linear order of genes within the genomes of related viruses is maintained Thus, the spacing and orientation of specific genes can be predicted in the genomes of Page 15 of 24 ... order ofthe DNA polymerase gene, ie ORF 9, andthe ORF and ORF 10 flanking genes, characteristic of gammaherpesviruses, is shown The position ofthe CODEHOP PCR primers used to obtain the sequence...
... climate Also the acidity ofthe soil, the composition ofthe organic matter, the humidity andthe availability of oxygen strongly influence the rate of decomposition 2.2 Compost The natural decomposition ... properties: The preparation anduseof compost ? it improves the soil structure ? it improves the resistance ofthe soil against the erosive action of rain and wind ? it retains water and releases ... management’ and Agrodok no 16: ‘Agroforestry’ Contents of this Agrodok This Agrodok concentrates on the preparation anduseof compost Chapter gives a recipe of making liquid manure and plant teas These...
... practice of composting In this chapter the important aspects of compost making are explained Attention must be given to the composition ofthe organic material andthe location ofthe heap The measurements ... put a stick in the centre ofthe heap about days after completing the compost heap or after the final turning over Leave it there for about to 10 minutes 12 The preparation anduseof compost After ... phase During the first stage of composting, the compost heap starts to heat up considerably This effect is known as fermentation and is the result ofthe breaking down ofthe complex and tough fibrous...
... around the top third andthe bottom third ofthe barrel, at a distance of 52 cm from each other Make another hole of cm in the base ofthe barrel Through this bottom hole the liquid from the decomposing ... 10: A boma and compost site (Source: KIOF and HDRA) Like on the drawing, a trench of 30 cm in depth is dug out behind the boma (A) The soil is put next to the trench The bottom ofthe trench ... than in the Indore Method, although the quality ofthe compost is about the same The major advantages ofthe Bangalore Method are: ? a saving of water; ? it requires less labour, because the heap...
... Dilute the contents ofthe drum 1:2 (to one part ofthe liquid manure or plant tea add two parts of clean water) Spray the crop at the stem and not at the leaves 48 The preparation anduseof compost ... air can reach the inside ? Mix the compost heap every two weeks by bringing the material at the bottom up to the top andthe material at the top down to the bottom After two months the compost ... produce 44 The preparation anduseof compost oxygen Because of these positive effects, much more compost than fresh organic refuse can be added to the water without difficulty, and more fish can be...
... out a layer of one ofthe materials: Use one third ofthe quantity ofthe recipe for one layer ? Water the layer with the molasses solution Use a watering can ? Put another layer of a different ... can find the addresses in the section ‘Useful Addresses’ If you 52 The preparation anduseof compost make Bokashi for the first time and you cannot buy the EM mixture easily, use clean and moist ... advisable to usethe anaerobic process The start ofthe preparation, the mixing andthe watering is the same as in the aerobic process When the mixing is done, you have to pack the mixture in...