Interactions of Extrusion and Ingredients for Aquatic Feeds

Joseph P. Kearns, Vice President Aqua-Feed Div., Wenger Manufacturing, Inc., USA

The extrusion process must produce feeds for various aquatic species, while meeting the specific nutritional needs and the demanding physical characteristics for a wide variety of aquaculture needs.  Typically, producers of aquatic feeds make a range of products for various species.  All of the possible combinations or differences in feeds for a given animal’s life cycle, as well as the overall different species in aquaculture production areas, requires the extrusion cooking device to be controllable with regards to all of the inputs to the system.  Ingredients, energy, pressure, water and steam, oils and the hardware used all need to be coordinated for final product characteristic control.  Feed sizes, densities, sinking rates, water stability, pellet hardness, water absorption and cell structure are just a few topics that come up when discussing an exacting feed for specific animals.  It is actually amazing how one machine has the ability to handle all of the above.  Extrusion is greatly enhanced by advanced control systems and effective tools to manage the feed production cycle.

Joseph P. Kearns is a graduate of Kansas State University and has been employed by Wenger for more than 40 years. He has spent a career watching and being involved in the feed production in the aquaculture sector.   He holds nine U.S. and foreign patents on aquatic topics relating to extrusion cooking. He has authored numerous publications on aquatic feed production as well as made presentations around the world.      

Durable sinking fish feed with low starch formulations and an example with insect meal as alternative protein

Urs Wüst, Director Product Management Aquafeed & Petfood, Business Unit Nutrition, Bühler AG, Switzerland

Formulations are changing and the level of starch is getting lower as well as the level of fishmeal. Fishmeal is being replaced by other protein sources, such as for example, different kind of gluten, soy bean meal and soy concentrates or peas. Depending on the quality of fishmeal, starch inclusions are varied and the extrusion process has to be adjusted accordingly in order to get the correct cook.

The physical quality requirements remain the same or are even increasing today due to the behavior of the different ingredients in the raw material and the changes in formulation.

The potential of using insect meals in fish feed diets show promising prospects.

Available studies indicate that a partial replacement of fishmeal will occur in the short or medium term.

In an extrusion trial with marine feed we have replaced the fishmeal with insect meal (Hermetia - black soldier fly meal) and show some data and processing conditions for optimal cooking and bulk density.

Urs Wüst is the Director Product Management Aquafeed & Petfood   for the Business Unit Nutrition, Bühler AG, Switzerland.  Until 2014, he was responsible for the market segment Aqua Feed and before for the technology and R&D for the market segments Feed, Petfood and Aquafeed. Mr. Wüst worked for more than ten years in Japan and Korea in sales, engineering and customer service as  Manager Feed Technology & Extrusion Systems at Bühler Japan. Prior to that he was Product Manager Food & Feed for analytical equipment at Büchi Lab-technology Switzerland, responsible for strategy, worldwide sales and development of new equipment. He was also Project Manager Feed & Oil Milling at Bühler Belgium, South Africa and Switzerland and Feed milling engineer at the Swiss Institute of Feed Technology (SFT).

Plant Extracts in Aquaculture Feeds: From Modes of Action to Practical Application

Clementine Oguey, Aqua Product Expert, PANCOSMA & Associates

The term plant extracts usually refers to components naturally occurring in plants, and namely regroups true plant extract such as essential oils or oleoresins, and nature identical molecules. These additives commonly suffer from a lack of transparency in the commercially available products and an inconsistency in their contents in active molecules, explaining the great discrepancy of activity between products containing similar compounds. However, as long as the additives considered have standardized formula and manufacturing process, their mode of action at recommended dosage can be consistently elucidated. This consequently explains the beneficial effects of these products on performance and health.

Historically, the effect of plant extracts is based on their antimicrobial activity. The minimum inhibitory concentrations of these compounds remain much higher than the standard dosages recommended in animal diets. This suggests that the effect of these products is not associated to a direct antimicrobial activity and highlights the importance to test them at their recommended dosage.

Well defined plant extracts such as standardized capsicum, turmeric oleoresins or cinnamaldehyde have been shown to modulate immunity at reduced levels and affected the systemic immune response of animals challenged with bacteria or viruses. The clarification of the mode of action of single plant extract associated to comparative physiology enable to develop combinations targeting specific applications.

Under standard animal production practices, the beneficial impact of these plant extracts on gut immune modulation can explain their efficacy to consistently improve gut function and subsequent fish resistance to disease and performance.

Plant extracts generally suffer from a lack of consistency to improve productive performance of target species. Consecutive trials demonstrated that compared to a negative control, a blend of three specific phytocomponents consistently increased body weight gain by and reduced feed conversion ratio in tilapia.

In addition to this beneficial impact on productive performance, the gut immunity effect of some plant extracts can also be exploited to increase the resistance of aqua species to diseases induced for example by bacteria.

Despite common belief, well defined and standardized plant extracts based feed additives are good tools to improve health and performance in current aqua production systems. The extended knowledge of the primary effects of these compounds opens new fields of utilization. However, the nutritional application of such products also involves taking into account gut physiology, immunology and microbiology, and farm practices.

Clementine Oguey received her B.S. degree in animal nutrition, and M.S. degree in Agro-food and health from ISAB, a French university specializing in agricultural engineering. Following her graduation in 2006, she joined Pancosam's R&D department in Geneva, Switzerland, where she currently works as a Technical Expert, focusing on the XTRACT® range of plant extract-based products, for all animals, including aquatic species. Her role is to coordinate all field trials worldwide, to provide technical support, as well as to publish scientific articles and participate in international conferences. She has been working on the practical application of plant extract based feed additives in aqua species for three years.

Advances in Amino Acid Nutrition of Shrimp

Dr. Alexandros Samartzis, Regional Technical Sales Manager, Evonik (SEA)

Alexandros Samartzis¹, Dhanapong Sangsue¹, Cláudia Figueiredo-Silva² and Girish Channarayapatna¹

¹Animal Nutrition, Evonik Industries, Singapore; ²Animal Nutrition, Evonik Industries, Germany;

Aquaculture is one of the fastest growing industries in the world. In 2013, total aquaculture production was 97.2 million tonnes globally that translates to 157.27 billion US$ with an annual percentage rate of 8.1% per annum. While Asian aquaculture production contributed to 91.78% of total world production with an impressive growth rate of 6.9% during 2013. In commercial aquaculture practices, feeds are responsible for the biggest share of the production cost which can be up to 80% in many cases. Fish meal (FM) is considered as an excellent source of nutrients (balanced amino acid profiles, essential fatty acids, and mineral content) and for that reason was the key ingredient in aquaculture feeds. Due to its high and increasing cost, nutritionists emphasize on reducing dependence and finding alternative protein sources to replace FM. Crustaceans attribute for the major share of about 28% of the total use of FM in aquaculture. During the last years, significant information were generated regarding the digestibility of nutrients including amino acids (AA) of practical ingredients. These data, allows the nutritionists to have better understanding of nutrient digestibility coefficients in order to formulate diets that meet the requirements of the defined production target (without being restricted by the limitations that FM imposes). The slow feeding behaviour of crustaceans such as, whiteleg shrimp (Litopenaeus vannamei), is an extra challenge that has to be addressed. The objective of this review is to present the available data on amino acid recommendations and digestibility co-efficients for whiteleg shrimp for an optimal but cost effective diet. The latest numerous up-to-date experimental studies indicate that FM substitution with alternative protein sources do not affect the growth, survival and feed conversion ratio of shrimp, as long as nutrient composition, including amino acid profile, are balanced to cover the specie’s requirements. The digestibility coefficient of crude protein and individual AA of many ingredients will be presented in detail. Finally, all the recent advances in the AA nutrition of shrimp will explained alongside the solutions to the challenges of the complicated feeding behaviour of crustaceans.

Dr. Alexandros Samartzis works for Evonik (SEA) Pte. Ltd. as a Technical Sales Manager for the Southeast Asia region specialized in Aquaculture and based in Singapore. My academic qualifications are; PhD in Aquaculture nutrition from Plymouth University in UK as well as an MRes in applied fish biology and an MBA from the Agricultural University of Athens, Greece. 

GART as a Platform to Investigate Disease Control Strategies Against AHPND/EMS in Shrimp

Dr. Niu Yufeng, research Scientist, Aqua UGent, Belgium

AHPND/EMS is currently one of the most devastating diseases in shrimp farms which occurs typically within 30 days of stocking in grow-out ponds and causes mortality up to 100%. This disease has a bacterial etiology and its causative agent has been identified as member of the Vibrio harveyi clade, most closely related to V. parahaemolyticus.

Recent research at the University of Ghent has shown that GART, the Gnotobiotic ARTemia platform, is a valuable pre-assessment tool to validate in vitro findings before testing on a large scale with shrimp. This model uses the brine shrimp (Artemia) under sterile conditions and provides a high-throughput and low-cost screening platform which, in combination with a number of Vibrio strains with virulence gradient, allows to investigate diverse disease control strategies under highly controlled conditions.

Dr. Niu Yufeng currently works as a post-doctoral researcher at the Laboratory of Aquaculture & Artemia Reference Center of Ghent University and is also involved in aquaculture business development between Europe and China for Aqua UGent.

As a joint PhD between Ghent University and Ocean University of China, Michael focused on the research of microbial management in the aquaculture industry and facilitated the collaboration between the two universities. During his PhD, microorganisms in the aquatic system were the core of his research. He studied the immunostimulatory effects of microbes leading to more robust animals against pathogen infections.

Feed for The Future: The Challenges and Opportunities for A Better and Sustainable Aquaculture Industry

Dr. M A Kabir Chowdhury, Global Product Manager - Aquaculture, Jefo Nutrition Inc.

The global fed aquaculture has been growing at a much faster rate than any other industry for the better part of the last three decades. In recent years, there are signs of sluggishness mainly because of lower than expected growth in China. Too many species, lack of better genetics and limited information on nutritional requirements of most of these species at various life stages has been a major bottleneck for the industry worldwide. In addition, increasing price of common feed ingredients, lack of quality feed stuffs, poor characterization of their nutrient profiles, poor understandings of anti-nutrients, lack of industry wide standard, poor labeling, and resistance to change or to accept innovative ideas, technologies and products are also some of the major contributing factors. The aqua feed industry could play a major role to reverse the trend in partnerships with the farming community and public institutions. The industry needs to invest significantly to improve the knowledge base on nutritional requirements, ingredient characterization and screening, and to educate the farming community. At the same time, local, regional or national governments should engage themselves in formulating, incorporating, implementing and enforcing policies on proper labeling, labour practices, environmental management, raw material standards, use of antibiotics and other chemicals, and other important issues.

To combat the continuing crises of quality raw materials, maintaining optimum environment and health, and for better production, plethora of products are available and new products are being developed almost every day in an already crowded marketplace. Similar to selecting a raw material, a due diligence needs to be given in screening these products. Most additives available for the industry today were originally developed for other terrestrial animals. From feed manufacturers’ and farmers’ perspectives, choosing a product should depend on species, farming conditions, and finally, the manufacturing parameters. This presentation discusses types of solutions currently available for various challenges being faced by feed manufacturers and farmers including some suggestions for a profitable and sustainable industry.

With broad knowledge and more than 20 years of field experience in  aquaculture production management and nutrition,  Kabir Chowdhury's  academic and research  excellence are reflected in numerous scientific communications published in various outlets.  He received his PhD in Animal Nutrition from the UG/OMNR Fish Nutrition Research Laboratory (FNRL) of the University of Guelph, Ontario, Canada and MSc from the Asian Institute of Technology of Thailand.

At his current position with Jefo Nutrition Inc., an animal feed additive company from Canada, he manages the worldwide aquaculture program for the organization.

Effect of an Algo-Clay Based Biocatalyst on the Digestive and Growth Performance of Juvenile Shrimp (L. Vannamei)

Maarten Jay van Schoonhoven, Aqua BU manager, Olmix, France

Vibriosis has long been one of the important causes for diseases in aquaculture, causing damage all along the shrimp production cycle. Vibrio bacteria occur commonly in the culture environment of shrimp, yet using good management practices can help limiting the vibrio outbreaks. Still there is continuous search for natural ways to control vibrio during shrimp culture. Olmix has developed a product associating clay and algae extracts, which aims at the improvement of shrimp performance through boosting digestive enzyme activity and improving the digestive balance. The purpose of this study is to evaluate the effect of this algae-clay mix supplementation on the digestive- and growth performance of L. vannamei. A lab scale test, at a University research facility in Thailand, showed a significant improvement in FCR and a significant increase in survival for shrimp groups fed the algae-clay mix supplemented diet. Histopathology showed reduced amounts of Vibrio in the hepatopancreas of shrimp fed diets supplemented with the algae-clay mix. This study highlights the capacity of algae-clay mix to improve the overall digestive efficiency and the gut health, resulting in a better growth performance.

Maarten Jay van Schoonhoven has worked for various companies involved in aquaculture in Europe, USA and Thailand. After starting with sales and account managing he was able to successfully introduce new products in different aquaculture markets. This involved working closely between the end users and the R&D group to find the best product and the best possible application. He recently joined Olmix to introduce their product range into the aquaculture market.

Pre-Processing of Feedstuffs to Improve their Feeding Value for Aquaculture Feeds

Dr. Dominique P. Bureau, Professor, University of Guelph, Canada

The agriculture, food and bio-fuel sectors produce numerous co-products or by-products and some undervalorized waste streams. There are opportunities to make use of undervalued products or waste streams or to improve the nutritive and economical values of existing feed ingredients. The presentation will review several recent attempts made at the University of Guelph to study the effectiveness of simple and potentially cost-effective techniques for processing feedstuffs of plant, microbial and animal origins prior to their incorporation in animal feeds. The perspectives and pitfalls for these approaches will be discussed.

Dominique P Bureau is a well-established research scientist with over 25 years’ experience in aquaculture nutrition. He has lead a dynamic research group, the Fish Nutrition Research Laboratory, at the University of Guelph since 2000, collaborating with numerous academic research groups, aquafeed manufacturers, ingredient suppliers and funding and regulatory agencies across the world and supervising a team composed of about 20 graduate students, post-doctoral fellows and research assistants.