http://rotifersolutions.com A Resource for Rotifer Production and Marine Larval Nutrition Solutions Fri, 09 Apr 2010 00:35:49 +0000 http://backend.userland.com/rss092 en ROTIFER PRODUCTION & MARINE LARVAL NUTRITION SOLUTIONS Our Closest-to-Nature Microalgae Feeds Provide Superior Nutrition, Cost-Saving Productivity, and Cleanliness Instant Algae™ RotiGrow Rotifer Products Uniquely Offer "Whole Cell - Whole Food" Nutrition In every hatchery, healthy, enriched rotifers are essential to grow healthy and vigorous fish larvae, but serious problems can quickly arise. Reed Mariculture ... http://rotifersolutions.com/?p=477 Calculating Feed Dose Feed rate is determined by Wet Weight Biomass produced (or more accurately by Dry Weight Biomass produced), the feed conversion ratio of the microalgal concentrate used and the efficiency of your grow-out protocols. Rotifer Count is a useful proxy for rotifer mass once rotifer mass per million ... http://rotifersolutions.com/?p=130 Information Coming. . . . . . . . . . . . . http://rotifersolutions.com/?p=103 Information Coming. . . . . . . . . . . . . http://rotifersolutions.com/?p=101 Typical Enrichment results Table F.4: Long Enrichment over 8 hours using N-Rich Standard with RotiGrow Plus as the Base Feed. Table F.5: 2 hour “Quick” Enrichment with N-Rich Plus followed by 6 hours using a maintenance dose of N-Rich Standard with RotiGrow Plus as the Base Feed. Table F.6: ... http://rotifersolutions.com/?p=99 Calculating Enrichment Feeds Enrichment feed is calculated by the wet weight of the rotifer harvested and enriched, not by rotifer count, as rotifer vary considerably in size. Screening the harvested rotifers prior to enrichment is not a recommended practice as it causes excessive rotifer stress. The preferred methods of determining ... http://rotifersolutions.com/?p=97 Choosing Enrichment Feed / Grow-out Feed Combinations that Best Fit the Needs of Your Hatchery How you choose to grow and enrich your rotifers depends on the level of enrichment that is needed and the enrichment constraints of your hatchery. Most hatcheries feed twice a day, in the morning and ... http://rotifersolutions.com/?p=95 Protocols for enrichment using Instant Algae products N-Rich with RotiGrow Plus, RotiGrow Nanno, and RotiGrow Chlorella General Information N-Rich feeds are exceptionally clean, effective and easy to use rotifer enrichment feeds that offers full fatty acid enrichment without stressing your rotifers. N-Rich is so clean that rinsing of rotifers after ... http://rotifersolutions.com/?p=93 Sources of nutrition for larva and rotifer There are two sources of nutrition for larval fish from enriched rotifers: 1. Digestible rotifer tissue – primarily the soft internal tissue of the rotifer, and 2. Gut-loaded feed released from the rotifer gut. There are four stages (sources) of enrichment for the rotifer: 1. Pre-enrichment ... http://rotifersolutions.com/?p=91 Ammonia Ammonia in water system reduces the excretion ammonia in the rotifer. Ammonia exists in marine systems in an “ionized” and “un-ionized” or “free” form. Both forms of ammonia are toxic, but un-ionized ammonia (NH3) is about 100 times more toxic that ionized ammonia (NH4). Unionized ammonia starts to become ... http://rotifersolutions.com/?p=89 Dissolved Oxygen Rotifers can survive very low levels oxygen levels. However, a drop in DO, even for a short period, can significantly stress the rotifer. At RMI we routinely measure DO using the % oxygen setting (calibration setting). We use this setting because it is the “partial pressure” of oxygen ... http://rotifersolutions.com/?p=87 Stress Rotifers do not like stress. They like stable conditions and do tremendously better when all system parameters remain stable for weeks on end. Stress can be result from low oxygen, prolonged feed loss (several hours) salinity changes, pH shock, temperature, ammonia spikes and numerous other factors. These factors compound ... http://rotifersolutions.com/?p=85 Dose for Biomass (or Million Rotifers) in the Culture Tank Feed rate is determined by the Wet Weight Biomass of rotifers in the tank at the time of feeding. For Batch Systems it is often more convenient to use rotifer count, standardized by the size of the rotifer, as a ... http://rotifersolutions.com/?p=83 Feed Handling Frozen microalgae concentrates (not including RotiGrow Chlorella) should be stored frozen for long-term storage. RotiGrow Chlorella is a refrigerated product and has a limited shelf life (4 weeks). To defrost the frozen concentrate, remove from the cardboard box and place in a refrigerator. 1 liter bags will defrost overnight. ... http://rotifersolutions.com/?p=81 Growing Rotifers with Instant Algae® Microalgal Concentrates General information Using Instant Algae microalgae concentrates in an existing system There is no need to modify you rotifer grow-out system configuration to use Instant Algae feeds (RotiGrow Plus, RotiGrow Nanno, Nanno 3600, RotiGrow Chlorella or Rotifer Diet) General system parameters and Useful ... http://rotifersolutions.com/?p=79 Feeding Dose in Continuous Systems vs. Batch Systems Because Continuous Systems and Batch Systems are simply two ways of looking at and managing the same rotifer population dynamic, you can use batch feeding protocols for a continuous systems. For example: If you are growing RMI “Mini-L 160” rotifers and ... http://rotifersolutions.com/?p=77 Progressive Density and Feed Management (Batch System) Batch Rotifer Systems start with a fixed inoculum and are allowed to grow in density over a period of 2 to 5 days. Batch systems are not equilibrium systems and values of all parameters from feed requirements and oxygen demand to ammonia increase ... http://rotifersolutions.com/?p=75 Equilibrium management (Continuous System) In a Continuous Rotifer System rotifers are harvested daily and the culture continues growing in the same tank. Continuous rotifer systems are equilibrium systems, and it can take some time to find the right balance. However, these systems can produce tremendous numbers of rotifers in a ... http://rotifersolutions.com/?p=73 Continuous vs. Batch (equilibrium feed chemostat vs. progressively increasing density and feeding) Continuous and batch rotifer system are simply two methods of managing the same rotifer population dynamic. In continuous systems you harvest 25% to 45% of the culture every day and “re-inoculate” with the remaining 55-75% of your culture ... http://rotifersolutions.com/?p=71 The objective of this section is to provide useful information regarding different rotifer production methods and principles for managing rotifer systems. General protocols and instructions for growing rotifers using the Instant Algae rotifer method will be discussed in the next section (E). Best Production Methods The variety of methods employed ... http://rotifersolutions.com/?p=69 Cost Microalgal feeds reduce all rotifer-related costs except the feed cost. Labor, space, management and other resource demands are all reduced. When all factors are considered most hatcheries find that the cost of using microalgal feeds is less, often far less, than alternative feeds. Further, the nutritional quality of the ... http://rotifersolutions.com/?p=67 Pre-enrichment Nutrition Boost Pre-enrichment is the process of pre-loading HUFA (DHA, EPA and ARA) lipids into the rotifer during production. Providing pre-enrichment is an extremely valuable quality for a grow-out feed. Pre-enrichment in the production stage increases the final level of enriched rotifer HUFA lipids and increases the proportion of ... http://rotifersolutions.com/?p=65 Net Biomass Conversion (feed productivity and waste production) Net biomass conversion is the rate at which feed biomass is converted into rotifer biomass and is excellent measure of the quality of a feed. The higher the net biomass conversion, the closer the feed matches the metabolic needs of the rotifer, making ... http://rotifersolutions.com/?p=63 Feed, Feed, Feed! Quality feed is an essential (and probably the most important) requirement for quality rotifers and clean and productive culture systems. The best all-around feeds are liquid microalgal feeds. Nannochloropsis- and Chlorella- based microalgal grow-out feeds are outstanding. Liquid microalgal feeds: Are exceptionally clean and easy to use. Allow ... http://rotifersolutions.com/?p=61 Visible cleanliness A dirty system is a nightmare: foam, protozoans, dirty rotifers, and clogged screens and more. Fouling reduces capacity, reduces rotifer value, increases labor cost and makes harvesting difficult. Worse, fouling can lead to unhealthy bacterial flora. Dirty systems are usually the result of dirty feed or poorly set ... http://rotifersolutions.com/?p=59 Rotifers must be healthy and vigorous: The culture needs to be healthy and strong to remain stable. The rotifers must be healthy enough to tolerate aggressive enrichment. Enrichment is often a source of significant stress for the rotifers and can result in significant numbers of rotifers that are dead, dirty, atrophied ... http://rotifersolutions.com/?p=57 The most important quality for a rotifer production system is that it be there when you need it. There is nothing worse than having your whole hatchery set for a production run, your eggs have just hatched, only to find that your rotifers are dead or in short supply. Rotifer ... http://rotifersolutions.com/?p=55 Production techniques are so varied that it is impossible to present them all here. This section focuses instead on critical principles used to choose, understand and operate specific production protocols, including: Qualities of a good culture system Qualities of a good rotifer including the characteristics of rotifer cultures that produce good ... http://rotifersolutions.com/?p=53 Why size matters: mouth gape, larval feeding efficiency, rotifer mass Larval Gape Considerable attention has been given to obtaining small rotifers. This is because the small mouth size (gape) of many marine fish larvae requires a small prey. While the relationship between measured mouth gape and prey size would seem ... http://rotifersolutions.com/?p=51 L-Type - Brachionus plicatilis Brachionus plicatilis is most easily distinguished by the blunt tips of the anterior spines of the lorica, easily seen when the corona is retracted. The most important attributes of L-Type rotifers for aquaculture are that they: Culture best at moderate temperatures (20-25 ºC). Easily tolerate cold storage. ... http://rotifersolutions.com/?p=49 Choosing the Right Rotifer Understanding of rotifer strains and the differences among them has expanded greatly in the past two decades. Originally only one species of rotifer, Brachionus plicatilis, was recognized in marine aquaculture. People recognized that there were differences among strains and began to denote rotifers as L-Type (large), ... http://rotifersolutions.com/?p=47 Other lipids – sterols, carotenoids, vitamin lipids, waxy esters and more Lipids are remarkably diverse and their functions are diverse as well. While the phospholipid and triglyceride classes make up the bulk of lipids, the other classes are critical as well. It is important that there be a rich nutritional ... http://rotifersolutions.com/?p=45 HUFAS and Phospholipids Given that our focus needs to be providing limiting nutrients in enriched rotifers, it must be said that in the past Highly Unsaturated Fatty Acids (HUFA) lipids and especially in Lipid Membrane form have been very difficult and critical to manage nutrients. Most marine fish larvae need ... http://rotifersolutions.com/?p=43 Limiting Nutrients The critical nutrients that require special attention are limiting or deficient nutrients. Individual amino acids, for example, are usually not limiting when a feed contains high levels of high quality protein (50%+). However, they can become limiting and critical when protein nutrition is poor. Lipids, proteins, carbohydrates, minerals, ... http://rotifersolutions.com/?p=41 Digestive bacteria and probiotics The digestive systems of larval marine fish are very immature when the larva fish first begins feeding. Digestive bacteria present in live feeds are critical for establishing the digestive bacteria of the larval fish. Thus, rotifers have a probiotic effect for larval fish. This probiotic ... http://rotifersolutions.com/?p=39 Rotifer Composition: Which parts are digestible Nutrition from rotifers can be divided into four functional areas: Lorica Egg Gut load Internal soft tissue Digestibility and nutritional significance of each of these components is a matter of debate; here is what we believe to be true: The Lorica is composed primarily of protein similar to Keratin ... http://rotifersolutions.com/?p=37 The Fish Egg Standard …we can make educated guesses about the needs of a larval fish by examining what nature provides… the nutritional profile of healthy eggs of each species… It is clear that the nutritional profile of healthy eggs is the intended nutrition larval fish need before first ... http://rotifersolutions.com/?p=32 Rotifers and the “Fish Egg standard” It is often said that rotifers are simply nutrition delivery devices that mirror the nutritional profile of what the rotifers themselves are fed. In many respects this is true. However, this view underestimates both nutrition and rotifers. The nutritional needs of first-feeding and early-stage ... http://rotifersolutions.com/?p=31 Rotifers are among the easiest of prey organisms to grow, yet they seem to be an endless puzzle and challenge to even the most experienced live feeds managers. For decades researchers have sought alternatives to rotifer production (and live feeds in general), and they have made advances. Still, quality rotifer ... http://rotifersolutions.com/?p=29 Understanding the Role of Rotifers and Microalgae For Marine Larval Nutrition Including comprehensive systems for growing and enriching rotifers, and for greenwater maintenance of rotifers with RotiGrow products from Instant Algae™ with emphasis on how we grow and enrich rotifers at Reed Mariculture. This document has been written for fish growers ... http://rotifersolutions.com/?p=27