In the first half of the webinar, there was a presentation given by Mr. Oliver Decamp Technical Director Grobest Group with the title “Nursery Food Protocols to Reduce EMS/AHPHD Risks.”
Mr. Oliver divides his talks into three sections. The first section is about introducing Grobest company and how they help farmers through their feed products. The Grobest Company was founded in 1974 and is located in Taiwan and eight other major shrimp-producing countries; one of them is in Indonesia. Grobest main focus is on aquatic nutrition and also disease reduction for high-value warm water fishes and shrimp. They have research development and production facilities located in Taiwan and China. Mr. Oliver further elaborates that Grobest is different from other companies because they focus on what most farmers want, including a higher survival rate and better growth, leading to higher yields and more profitability.
Grobest realizes this by focusing on functional ingredient supply, intestine system care, health improvements, and daily health care. Grobest has developed propriety feed additives, probiotics and premix formula. The company has four feed mixes: Neopower, Biomax, Lactonin, and Fucogen with unique characteristics: (1) attract ability and palatability; (2) immunostimulation; (3) hepatopancreas and gut health; (4) damage repair; (5) and antioxidants. With these different varieties of additives, Grobest can blend these additives according to the benefits expected from the feed production.
In the second section of his presentation, he discussed the problem of early mortality syndrome (EMS) in the early stages of the shrimp cycle and how to overcome the EMS problem via nursery and quality of feed. The premature mortality syndrome can lead to shrimp mortality of 100%, and it hits very early in the life cycle of shrimp. The disease usually affects shrimp in the first 30 days of its growth cycle, i.e., 90 to 130 days.
A nursery is needed to solve the EMS problem because the nursery would allow the farmer to control the production cycle in the first 30 days. The nursery also will enable farmers to monitor the Postlarvae (PL) from the first few days of hatchery until they are transferred to the grow-out ponds. Then, if there is a problem, it can be observed more efficiently, such as destroying shrimps with EMS symptoms. This shows that nurseries have an essential role in controlling the culture in the early stages of the shrimp life cycle. In addition, their high biosecurity makes nurseries great, allowing farmers to grow PL in high density from PL 10-12 in 1 to 4 weeks. The nursery also makes farmer easier to control the entry of pathogens, limit the exposure of early-stage shrimp to less controlled grow out production, makes it easier to control feeding, thus improving overall productivity and quality of the juveniles produced and maintaining the accumulative growth of organic waste that affect vibrio growth.
Nevertheless, there are a few points to consider when running a nursery. First is the design of the nursery phase; second is the water treatment before stocking the nursery; third is the daily management of the nursery like feeding and water quality; and last is how you transfer the shrimps from the nursery to grow-out ponds. When moving PL from hatcheries to a nursery, there are crucial points to consider in the process; for example, in Vietnam, after the PL are delivered from the hatchery, they are kept indoors and go through a primary inspection for pathogens, then the packaging containing the PL are soaked in disinfectant, after that they are transferred into the nursery pond to acclimate to the water temperature before conducting PL count and finally release them into the nursery facility.
Finally, in the last section of his presentation, he gave an example of a Grobest operation in Vietnam, particularly about the advantages of combining nursery and good quality of feed-in culturing shrimp. The nursey diet used in Vietnam has 45% protein, 5% lipid and 50% other overall specs of the diet. This diet was fed to PL SIS broodstock grown in a semi-commercial, experimental nursery setup, with a density of 2,000 pl per cubic meter with a nursery phase of 20 days. So, using this type of breeding and quality feed can result in a fairly good growth rate and ultimately lead to an increase in shrimp production.
In this webinar, the second material entitled “Nursery Ponds in Indonesia and a Few Critical Notes” was presented by Pak Haris Muhtadi who currently serves as Director of PT. CJ Feed and Care Indonesia.
Pak Haris divided his presentation into three parts. In the first part of his presentation he explains about Nurseries in Indonesia. Nurseries are not new in Indonesia, since the 90s there have been nurseries in several areas such as Lampung, East Java, and Bali but with different goals from now, at that time the goal was how to shorten the cultivation period because at that time they did not yet have pond liners for their ponds, which causes the soil to age due to water and also causes organic matter buildup. Another goal in shortening the cultivation age is to be able to harvest more than twice a year.
Pak Haris submitted a report from the CJ technical team from Medan, Maluku, Lampung, Central Java, and West Java that apparently nursery has been discussed a lot but has not been popularly adopted among the shrimp farmers in Indonesia. There are several reasons why there is still some skepticism. Shrimp farmers that have tried nurserys still find that their shrimps are still prone to AHPHD/EMS, and face serious problems when transferring shrimp from the Nursery to the grow out pond. Pak Haris hopes that with this webinar it can encourage farmers to retest the hypothesis that nurserys can be a way to solve AHPHD problems.
Nurseries are becoming a trending topic because they are hypothetically assumed to solve disease related problems, especially Early Mortality Syndrome (EMS)/AHPHD). EMS begins to attack shrimp at the age of 10 to 20 days, and therefore shrimp farmers assume that nurserys are a good preventive measure against EMS by providing treatment at the beginning of the shrimp culturing cycle and the shrimp that are transferred from the nursery to the grow out ponds have passed their critical period.
In the second part of his presentation, Mr. Haris explained that in the General Guidelines for Nursery Program, there are 8 important points, namely (1) Setting the windmill and blower with sufficient DO supply. (2) Siphon the bottom of the pond to remove organic material that can be used as vibrio growing material. (3) Change of water every 3-8 days with 10% water (4) Maintenance of water quality by treating bacteria and minerals. (5) Monitor water quality 2 times a week (6) Check PCR periodically, (7) Sampling periodically every 5 days, (8) Transfer to a grow out pond with a minimum weight of 0.5gr per shrimp.
Pak Haris also explained about the feeding program for nurseries and the process of transferring the shrimp from the nursery to the grow out pond. For the feeding program, the feed used for nurseries are a special type of feed that is rich in protein, amino acids and minerals that are far superior when compared to the feed commonly used in grow out ponds. The second is using a combination of regular and special feed based on the age of the shrimp, and the last is the frequency of feeding, which is six times a day.
For the process of transferring shrimp from the nursery to the grow out pond, Pak Haris says that according to the experience of the CJ team and the farmers who have been interviewed, the most serious problem is the process of transferring shrimp from the nursery to the grow out pond. The best way to transfer shrimp is to avoid stressing the shrimp to reduce the risk of the shrimp dying during the transfer process. Shrimp can be transferred starting from the age of 23 days with a minimum weight of 0.59 gr per head. an important thing that also needs to be prepared is the equipment such as oxygen, scales, drains, and a feeding tray two by two meters.
For the final part of the presentation, Mr. Haris delivered a post scriptum of cases in Indonesia. For the first point, he said that the initial assumption of nurseries as prevention of AHPHD needs to be re-examined, second problems when transfering shrimp so far have not been completely solved, third after transfering the shrimp farmer need to pay attention to changes and differences in water quality from nurseries to grow out ponds. Fourth the quality and types of feed specifically for nurseries are factors that support the success of nurseries and grow out ponds. Fifth, Biosecurity is mandatory, and the last point is the benefits and costs need to be recalculated until proven technicalities are found.