The area under culture of freshwater fish (earthen ponds and cages) in 2014 was 131,000 hectares with production of approximately 415,121 tonnes. The high production species are tilapia, hybrid catfish, silver barb, snake skin gourami, striped catfish, giant prawn, snake head, giant gourami, soft-shell turtle and frog, respectively. The area under culture of marine fish (earthen ponds and cages) in 2014 was 1468 hectares with production of 19,087 tonnes. Most of the production was seabass (16,502 tonnes) followed by grouper with production of 2,585 tonnes.

The most important aquaculture industry of Thailand is marine shrimp. Unfortunately, the outbreak of acute hepatopancreatic necrosis disease has severely impacted the shrimp industry since the end of 2012. Shrimp production dropped to 480,000 and 256,000 tonnes in 2012 and 2013, respectively. By 2014, the area under culture (earthen pond) of white shrimp remained 261,169 tonnes.

Approximately 90% of aquaculture produce in Thailand are fed with a complete commercial feed, which provides sufficient nutritional value and is ready to use. During the past 10 years, the estimated use of fishmeal was about 17 to 27 thousand tonnes, soybean meal demand was between 33 to 44 thousand tonnes and corn consumption was from 19 to 26 thousand tonnes. However, aquaculture feeds represented only about 5% of all animal feed consumption.

Since 1992 the Thai Department of Fisheries (DOF), through the Aquatic Animal Feed Research and Development Division, has been responsible for the licensing and registration of feed to be sold for commercial purposes according to Animal Feed Quality Control Act B.E. 2015. This Act is intended to provide quality and safe feed in compliance with the DOF aquatic feed standard, to meet consumer health concerns. Additionally, DOF developed guidelines for good manufacturing and HACCP systems. There are five types of licenses: Feed manufacturing license, feed import license, feed distribution license, import permit of aquatic animal feed into the Kingdom of Thailand and feed registration. DOF is responsible for four types of feed to be sold, namely complete feed, concentrated feed, premixes and supplemental feed, and this responsibility is limited to eight species of aquatic animal (catfish, freshwater herbivorous fish, freshwater prawn, marine shrimp, marine carnivorous fish, freshwater carnivorous fish, soft-shell turtle, and frog). At present, there are 66 registered aquaculture feed manufacturers, five times more than in 1990. Twenty six out of the 66 feed mills are producing both shrimp and fish feed, 23 are registered for fish feed production only and 17 for shrimp feed production only.

Recently, the main feed ingredients used in aquaculture feed production of Thailand has been soybean meal and soybean products (41%) following by fishmeal (22%), wheat flour and wheat products (13%), rice products (7%), corn (6%), cassava products (5%), land animal protein sources (3%), plant protein sources (2%) and fish oil (1%), respectively. Meanwhile, domestic fishmeal production in 2016 was 3% of all feed ingredients, soybean and soybean meal made up about 25%, and other carbohydrate-producing plants accounted for 60% of total production base on the information of the Thai Feed Mill Association.

High quality fishmeal is a priority for aquaculture feed production especially for shrimp and marine fish and this has significantly affected feed cost. The supply of fish meal from local production has been insufficient and the rest had to be imported. Recently, local fish meal production faced a challenge from illegal, unreported and unregulated (IUU) fishing. This situation has a negative impact on aquaculture businesses and may become more problematic in the future due to the possibility of the issue resulting in non-tariff trade barriers. Research on the use of alternative feed ingredients in aquaculture feeds is needed. However, feed ingredients from local raw materials and waste from agriculture and industry have been utilised by many competing interests.

Research on the use of alternative ingredients in aquaculture feed in Thailand has been focused on the replacement of fishmeal by other ingredients. These may be divided into three approaches as follows:

• Substitution or replacement of fishmeal by plant protein meals such as soybean meal, sesame meal, palm kernel meal, peanut meal and coconut meal.
• Substitution or replacement of fishmeal by terrestrial animal protein meals and by-products and others such as poultry meal, pig meal, meat and bone meal, hydrolysed feather meal, silkworm and silkworm hydrolysate, shrimp head meal and hydrolysated product, fish visceral hydrolysate and apple snail meal.
• Partial replacement or the combination of soybean meal with other plant protein meals such as sesame meal, maringa leaf and coconut meal.

Trials have been conducted with major cultivated species such as hybrid catfish, tilapia, sea bass, white shrimp, striped catfish, giant freshwater prawn, silver barb, gourami, frog, grouper and swimming crab.

In Thailand, most raw materials and waste from agriculture and industry have been utilised by other sectors and competing uses such as livestock, pet foods, fertilisers, biofuels and in some cases by direct human consumption. Thus aquaculture feed manufacturers are highly dependent upon importation for high quality feed ingredients. There are many factors that affect the selection of alternative of local feed ingredients. Non-nutritional aspects are price, palatability, market availability (domestic or imported), physical characteristics (easy to use/to transport), presence of contaminants and market acceptability (eg. IUU fishing, GMOs, labour issues and carbon foot print. Meanwhile, nutritional aspects such as proximate composition, amino acid profile, fatty acid profile, energy content, vitamin and mineral contents, anti-nutritional factors and nutrient digestibility are definitely additional factors that must be taken into account.