5.1 Survey of the feed manufacturing industry
5.2 Recent developments in pelleted feed manufacture
5.3 Feasibility of using manufactured feeds for aquaculture
There are four major advantages in using artificial feeds for intensive aquaculture purposes. These are: (i) uniformity with regard to quality; (ii) nutrient balance for maximum growth effects; (iii) adequate and easy application; and (iv) generally lower cost.
Because compound feeds are formulated according to precise nutrient specifications, product quality is uniform and assured even when there is a need for the manufacturer to make ingredient substitutions to overcome temporary shortages of certain ingredients. On the other hand, natural food supplies tend to vary in nutrient composition depending upon factors such as stage of maturity of plant and animal organisms that constitute these supplies.
Nutrient requirements of fish are affected by the life stage they are in. For example, very young fish have higher requirements for protein in the diet including protein quality. Artificial diets can be specially formulated to meet such requirements.
An often serious problem in intensive aquaculture is the adequate provision of food for the animals. It is difficult to maintain the required density of food organisms in a culture system. On the other hand, artificial feed can be given as and when required at satiation levels.
The high cost of supplying natural foods for larval rearing is well known. Also, the increasing scarcity of traditional fish foods such as trash fish and the high cost of available supplies make their continued use uneconomical. Artificial feeds, based mainly on feedstuffs of plant origin, are less expensive and can, with proper balance of nutrients, produce comparable results.
Artificial feeding of fish, however, poses peculiar problems for both the fish farmer as well as for the feed manufacturer. Unlike natural foods which normally are present as discreet living forms, and therefore biologically stable until consumed, artificial feeds undergo rapid nutrient loss through normal deteriorative processes and leaching by water unless quickly consumed. Moreover, once in water, feed aggregates tend to disintegrate and separate into their ingredient components, thus losing their original nutritional properties. Therefore, a successful artificial feed, apart from meeting nutritional requirements should have good water stability and acceptance by the feeding animal. To produce feeds with the desired physical characteristics, processing is required. Commercial processed fish feeds are either in the dry or moist pelleted form.
Dry Pelleted Feeds
Production of dry sinking-type pelleted feed appears more practical for feed manufacturers. With proper selection of ingredients, and employing manufacturing procedures designed for high-quality pellet production, products possessing good water stability can be obtained. Use of artificial binders, in most cases, raise the cost of products to prohibitive levels, and is avoided whenever possible. Important prerequisites for water-stable dry pellet production lie in the manufacturing process. Ingredients should be as finely ground as possible (in practice, a hammermill fitted with a sieve of hole diameter no greater than 2 mm) so that during the steam conditioning phase maximum starch gelatinization takes place. This process brings out the adhesiveness of the starch molecule and at the same time increases the digestibility of the nutrient, since fish utilize raw starch poorly. Proper processing procedures for pelleted feed manufacture have been described in an earlier ADCP report 1/.
1/ ADCP/REP/80/11
Apart from nutritional consideration, dry pelleted feeds have certain advantages conducive to their use in intensive aquaculture. These include:
(i) ready availability. Except for the production of extruded floating-type feed, the technology for large-scale manufacture of dry pellets exists in most developing countries. Feedmills equipped for manufacturing pelleted poultry feed can also produce sinking-type dry pelleted fish feed with minor modification to the equipment - only the hammer mill screen needs to be changed to one of smaller hole diameter for finer grinding of ingredients;(ii) long shelf-life. Because the product is dry, it has a fairly long shelf-life. Dry pelleted feed has a shelf-life of at least two months under good storage conditions in the tropics; and
(iii) easy application. Dry feed is easy to dispense. Control of feeding can also be easily exercised to ensure adequate feeding and minimum feed wastage.
One major disadvantage of dry pelleted fish feed is their apparent high cost. Such products are usually made from "conventional" ingredients which have competitive use in the manufacture of feed for livestock. However, because good quality compound feeds are usually more efficient, they may be more cost effective than traditional type feeds.
While dry, pelleted aquaculture diets have gained wide acceptance in Western industrialized countries, they have been introduced only recently in developing countries. Judging from initial response of catfish fish farmers in Thailand, there is considerable resistance to their use. There are a variety of reasons for this resistance, some of them related to product quality and others to high cost and traditional preferences of local fish farmers.
Sinking-type pelleted fish feed inspected by the author in Mexico, Venezuela and Thailand showed a distinct need for product improvement with regard to physical appearance. Pellets were often not graded for size, thus leading to wastage when fed to fish. Furthermore, quite frequently, the mills produced quantities far exceeding market demand, resulting in later sale of products that had deteriorated in quality. Feeds that were supplied to a Government trout hatchery had been in storage for up to eight months before finally fed to fish. The result was high fish mortality following the appearance of symptoms of deficiencies in Vitamin C and E, two vitamins which are particularly affected by prolonged storage.
Another resistance factor is the relatively high cost of factory manufactured feed. To fully appreciate the fish farmer's caution with regard to use of manufactured feed, one might look again at the Thai experience (see later in this section).
At present there are no commercial feed mills among the countries surveyed that are devoted entirely to the manufacture of floating-type pellets. Indeed, only one feed mill (in Thailand) was originally designed solely for fish feed manufacture. This factory, which now also produces feeds for other livestock, is equipped with extruders for the manufacture of floating-type pellets for Clarias. Although there are various important advantages in using this type of feed, its acceptance has been limited due to its high cost.
Moist Pelleted Feeds
Traditional feeds for aquaculture have a high moisture content. Examples are single-ingredient feeds such as trash fish (whole or cut-up) for carnivores, and crop and vegetable wastes for herbivores. More recent acceptance of the balanced-diet concept gave rise to more complex feeds consisting of two or more main ingredient components together with vitamin and mineral supplements. While feeds with a high moisture content are generally more readily accepted by fish, compound feeds of this kind have low water stability. These feeds also lack the commercial attributes of dry diets, such as ease of handling and long shelf-life. Due to escalating energy cost, however, moist feeds are regaining popularity among aquaculturists.
In Thailand, where traditional feeding practices are widespread for intensive Clarias culture, trash fish are minced with rice bran and/or broken rice to produce a moist-type pelleted feed that contains between 50-70 percent moisture. This processing method has two main effects. The first is the integration of feed components into a homogeneous mixture. Secondly, natural gums present in trash fish aid in the binding of the ingredient components to give a fairly water-stable product after the mixture has passed through a mincer/extruder. The feed is usually prepared fresh.
Despite their widespread use in aquaculture, there is still no commercial production of moist fish feeds. The obstacles for development of an industrial product are formidable. Technically, problems associated with handling and storage of the final product are the most difficult to overcome. A successful product ready for immediate use will have to be stored in rigid containers. Even this measure will not prevent the "caking" up of moist pelleted feed resulting from handling and prolonged storage. An alternative would be to manufacture the product in large block or slab forms to be further processed (extruded) on the farm. Due to their high moisture content, moist feeds undergo rapid spoilage during storage unless the moisture content is at or below a permissible level, the product pasteurized and chemical agents added to prevent yeast and mould growth 1/. Although processing cost for the manufacture of moist feeds will be lower than for dry feed, additional
1/ Semi-moist foods have been successfully developed by the pet food industry. In these products, it has been shown that an expression, known as "water activity", aW, determines the susceptibility of the products to bacterial spoilage. Water activity is governed by the following equation: where,
where,
NW = number of moles of water
NS = number of moles of solute.A semi-moist food with a low aW value is desirable. A value of 0.79 or lower prevents yeast growth, while a value of 0.65 or lower effectively stops mould growth as well. Most semi-moist pet foods have an aW value of 0.85 or lower. At this level, bacterial growth (by far the most serious threat) is checked; chemical agents are added to prevent the proliferation of both yeasts and fungi. Semi-moist food products usually contain up to 35 percent moisture. expenses for packing, storage (refrigeration may be necessary) and handling (including the added cost of transporting water in the product) may exceed any savings in processing cost. This is probably the reason why moist aquaculture feeds have not been marketed. For the fish farmer who is equipped to make his own feed, moist feeds provide savings. He can take advantage of supplies of cheap ingredients such as slaughterhouse wastes and crop residues as substitutes for more expensive conventional feed ingredients.
Binary-type diets - the other alternative
As pointed out earlier, the Thai catfish farmers' feeding practices continue to be very much influenced by tradition. The tradition of using trash fish and rice bran probably developed during the period when the list of readily available feed ingredients was still quite limited because of lack of demand by a yet undeveloped feed industry. The quantity of trash fish reduced to fish meal annually 15 years ago, for example, was very small and trash fish was then quite cheap and plentiful. Rice bran, on the other hand, had always been readily available, as it still is today, in those parts of the country where fish farming activity is concentrated. The result was the development of moist, binary-type feed that was easy to prepare and inexpensive to use.
The success of a commercial replacement for traditional farm-prepared feeds will be determined not only by the new product's ability to support rapid growth with high percentage fish survival at market time, but also by its cost effectiveness. Manufacturing and marketing costs of compound feeds have risen dramatically over the past decade as a result of a tenfold increase in energy cost. Production cost of dry pelleted feeds is particularly high. Apart from cost factors, the farmers' prejudice against new diets (in this case, of feeding dry pelleted feed opposed to their traditional moist feed) has to be overcome. Such prejudice can be deep rooted.
In order to reduce the cost of manufactured feed yet make as little change in feeding methods as possible, another binary-type feed should be developed in which one of the binary components is an ingredient, or mixture of ingredients that is readily available in the vicinity of the farm (e.g. rice bran) and the other component, a feed concentrate which, when mixed with the other component of the binary, will provide a well-balanced diet for full feeding of fish. Instructions will have to be provided on the proportions the binary components should be combined for a specific feeding purpose. The mixture can then be made into the moist pelleted feed which the fish farmer is most accustomed to use in most cases. Significant savings arise from lower transportation expenses. Other savings will be from cheaper processing costs at the farm, the amount depending upon processing methods used and energy source available.
The world's feed manufacturing industry, which has its origins in the western industrialized countries, arose from the need to supply large quantities of meat products for urban consumption. The industry initially provided simple services to farmers such as grinding of coarse grains and blending fodders in the proportions dictated more by available supplies than by needed balance of nutrients in the final mixtures. As the demand for animal products increased, new methods for their production became necessary. It soon became apparent that such production could only be achieved by adoption of intensive animal husbandry, whereby traditional feeding methods had to be replaced by more efficient ones based on new knowledge concerning the nutritional requirements of farm animals for growth and production. This new knowledge, together with the discovery that farm animals responded well to diets containing a wide variety of food grains and agricultural by-products, provided basic dietary nutrient requirements were satisfied, marked the beginning of the compound feed manufacturing industry.
Development and expansion of the industry thereafter has been rapid, particularly in the U.S.A., where the demand for feed grains, created by the industry, was easily met.
As output of the industry increased, so has its level of sophistication. The development of compound feed for aquaculture has brought the industry to the highest level of sophistication with the introduction of extrusion technology for the production of floating-type pelleted feed.
The feed manufacturing industry in developing countries in the tropics is of fairly recent origin. It came with the introduction into those countries of high-yielding breeds of poultry which require properly balanced feed for optimum production of meat and eggs. There is no concensus as to when the industry was established in those areas, although it is generally believed that countries such as Malaysia, Thailand and India saw the building of their first feed mills in the late fifties and other countries such as Nigeria and Nepal considerably later. Mills in other countries with close proximity to the U.S.A., viz., Mexico and Venezuela, were built a little earlier.
Growth and expansion of the feed manufacturing industry in the developing countries followed a somewhat different pattern compared to that in the Western countries. Mills were designed for manufacture of compound feed from the onset. The product-mix of mills in the tropics is also different. The bulk of production goes to poultry and pig feeds. The mills in most of the ten countries dealt with in this report depend on imported feed grains and other crucial ingredients such as fish meal and oilseed meals and cakes. This dependency on external supplies of raw materials undoubtedly is a major constraint to development of the industry in those countries. Nevertheless, the average growth rate of the industry there during the past two decades had been very impressive. Some countries, like Thailand and Malaysia, had averaged about 20 percent with the most rapid growth occurring during the first ten years. Others, such as India and Nigeria, despite major (but dissimilar) constraints, have still managed an average growth rate, over the last 20 years, of 10 percent/annum.
Although gaps still exist between developed and developing countries concerning knowledge of animal and fish nutrition, and concerning application of technology for animal production, the level of sophistication in feed manufacturing technology is similar, largely because of the setting up of turn-key mills, incorporating the latest technology, in developing countries. The majority of the countries involved now have fully integrated and automated feed mills that have high production capacities while using minimum labour.
Although few countries among those surveyed are presently manufacturing compound feed for aquacultural purposes, those with an established capability for producing pelleted feed for conventional livestock can also provide this service with upgrading of milling processes to produce products with desired qualities for efficient application. Design and construction of fish feed production facilities in developing countries will be the subjects of a future report.
Egypt
In common with the other countries surveyed, the Egyptian feed manufacturing industry's growth and modernization in recent years has been greatly aided by rapid expansion of the poultry industry. One main difference is the Government's almost total monopoly in the feed manufacturing industry in Egypt. There are six major feed mills in the country, three in Cairo, one in Helwan, one in Alexandria, and one mid-way between Cairo and Alexandria. Between them, the mills produced an estimated 500 000 tonnes of poultry feed in 1981. Other smaller mills produce another estimated 100 000 tonnes. A good portion of all compound feed produced went to meet the needs of the Government-owned General Poultry Company which had targeted poultry meat production at 200 000 tonnes for that year. The Company also owns a large poultry egg production operation which produced an estimated 300 million eggs in 1981. Although the annual consumption of cattle food is said to be at least 1 million tonnes, much of this undoubtedly is in the form of roughages and fodders. There is no commercial production of compounded feed for fish.
The principal ingredients used in feed manufacture that are of local origin are: maize, maize gluten meal, rice bran, wheat bran, sunflower seed meal, cottonseed meal, linseed meal, meat meal, bone meal and poultry by-products. Fish meal and soyabean meal are also imported in large quantities, mainly as sources of high-quality protein for poultry feed. Feed mills obtain their raw materials under a quota system that favours them with adequate supplies and subsidized prices. However, mills are not permitted to resell ingredients.
The quality of compound feed produced in the larger mills appeared good. These mills can be easily upgraded to produce pelleted feed for fish.
India
The feed manufacturing industry in India was established about 15 years ago. In 1967, the Compounded Livestock Feed Manufacturers' Association of India (CLFMA) was set up to represent the interest of manufacturers in the Government (primarily at the state level), cooperative, and private sectors. More than 50 members of CLFMA operated 77 plants in 1979 with an estimated designed capacity of 1.73 million tonnes/annum. However, mills were operating at half this capacity, producing an estimated 900 000 tonnes during that year. Of this quantity, two-thirds were for conventional livestock, mainly dairy cattle, and the remaining third for poultry. There was no commercial production of fish feed although a state-owned mill in West Bengal was testing a product for carp polyculture. Growth of the industry, as reflected by the following yearly production figures for CLFMA members, during a 14-year period, had been erratic, but still showed an impressive average 14 percent compounded over the period.
Compound Feed Production by CLFMA Members
(excluding public sector and small-scale units)
|
Year |
Cattle and other feeds |
Poultry feeds |
Total |
|
1964 |
25.0 |
14.4 |
39.4 |
|
1965 |
50.3 |
28.4 |
78.7 |
|
1966 |
69.4 |
39.2 |
108.6 |
|
1967 |
91.5 |
42.6 |
134.1 |
|
1968 |
94.5 |
47.1 |
141.6 |
|
1969 |
131.3 |
57.7 |
189.0 |
|
1970 |
125.4 |
84.3 |
209.7 |
|
1971 |
144.8 |
114.7 |
259.5 |
|
1972 |
188.5 |
183.0 |
371.5 |
|
1973 |
238.3 |
163.8 |
402.1 |
|
1974 |
275.4 |
164.6 |
440.0 |
|
1975 |
275.3 |
143.9 |
419.2 |
|
1976 |
313.8 |
160.5 |
474.3 |
|
1977 |
401.8 |
204.2 |
606.0 |
Sources:(i) the Standardisation and Control of Quality of Animal Feeds by H. Bhagwan in 'Proceedings of the Conference on Animal Feeds of Tropical and Sub-tropical Origin', Tropical Products Institute, 1975, London(ii) Animal Feed Industry in Developing Countries by Desmond Bird, Milling Feed and Fertilizer, June 1979
Production by CLFMA members is said to account for 80 percent of all compound feed manufactured. On this basis, the total annual production for 1979 was believed to be a little over a million tonnes. Two large private enterprises, Hindustan Lever and Shaw Wallace, dominate the private sector in compound feed manufacture. Hindustan Lever, the industry leader with 14 mills, accounted for 10 percent of compound feed produced that year. Total feed consumption of all livestock in the country had been estimated at around 40 million t in 1979.
The world's feed industry is characterized by low profit margins. In India profitability is further influenced by competition between the private and public sectors. Returns on investment apparently have not been high enough to encourage capital spending to keep up with new technology introduced into the industry. Few mills produce pelleted feed, and at the Delhi plant of Hindustan Lever this type of feed was still produced using machines with old-fashioned horizontal, rotating plate dies rather than the more advanced ones employing fixed vertical ring-dies. While the old pelleting technique remains suitable for producing large-size pellets for cattle and hogs, it is inadequate for making small-size pellets of sufficient hardness and compactness. The Indian machine tool and engineering industry has demonstrated its ability to fabricate the new type pelleting machine, since such machines made here have been offered for sale in Nepal. Adoption of the more recent pelleting technique would be required for making small-sized pellets that not only possess hardness but also remain water stable when fed to fish.
A laboratory size feed pelleting machine was recently installed at RLCI in Dhauli for making test experimental diets for carps. The mill, manufactured by California Pellet Mills Co. in USA is capable of producing up to 100 kg product per hour. Dry mash feed mixed with 7 percent water before the pelleting operation yielded very good quality pellets. The water substitutes for steam which is difficult to add for a mill of such size.
Malaysia
The feed milling industry of Malaysia is of fairly recent origin. Begun in 1960, it has grown into perhaps one of the biggest manufacturing industries in the country. There are at present about 70 feed mills throughout peninsular (East) Malaysia, with an additional six mills in the West Malaysian states of Sabah and Sarawak. An estimated 600 000 t of compound feed are produced annually with poultry feeds accounting for more than two-thirds of the total. The rest is mainly for pigs. Total annual demand for mixed feed has been estimated at more than 1 million t. The balance, therefore, is produced by larger farms which do their own feed mixing.
The industry relies very heavily on imported raw materials, since the country has practically no output of feed grains and inadequate production of cereal by-products such as rice bran and wheat bran. Although palm kernel oilcake is available in great abundance, its use in feed for monogastric animals is limited by the material's high-fibre content. The country's reliance on imported fish meal has been reduced somewhat during the last five years. The principal ingredients used in manufactured feed in Malaysia are in maize, sorghum, rice bran, wheat bran, fish meal, meat meal, soyabean meal, coconut oilcakes, groundnut oilcakes, palm kernel cakes, molasses and kathin meal. Product quality is frequently monitored by the Government under a Feeds Act instituted in the early sixties.
An unsuccessful attempt was made a few years ago by the country's largest feed manufacturing group, Gold Coin Mills, to make diets for aquaculture on a commercial scale. It started when a fish farmer wanted some custom-made carp feed made by the Company. Small quantities of this feed were made over a period of six months, after which further orders for it were stopped. The farmer had cited high cost as the reason for ceasing purchases. The feed that was delivered was in mash form.
Although the Malaysian feed manufacturing industry is equipped with machinery that can be easily modified for sinking-type pelleted fish feed production, there is still no expertise within the industry for commercial production of such products. Existing equipment will have to be upgraded for fine grinding of ingredients. Proper selection of raw materials and more stringent manufacturing procedures will have to be adopted for production of pellets possessing high water stability.
Mexico
Mexico has a modern animal feed milling industry. It comprises about 40 companies operating twice as many mills throughout the country, producing complete and supplementary feeds. Total production is expected to reach 5 million t in the current year with almost 70 percent accounted for by poultry feeds. During the past decade the industry has been growing at a fairly high rate of 8.3 percent/year. This rate is expected to increase slightly during the present decade. The industry is dominated by two foreign-owned companies (Purina and Anderson/Clayton), which together account for 50 percent of total feed manufactured in the country. ALBAMEX, the public sector milling company, has the capacity to produce from its two mills half a million Cons annually. The ALBAMEX mill at Guadalajara is one of the most modern in Mexico, with a daily production capacity of 500 t. The bulk of this production is pelleted feed for poultry and pigs. It is also newly equipped with stainless steel extruders for making expanded soya-based food for human consumption. These extruders are similar to those used for making floating-type pelleted feed for fish. The mill has been producing small quantities of feed for DEPES's trout hatcheries and for the small aquaculture industry. Commercial production and demand for fish feed as a whole remains very limited.
Through CONASUPO, the Government controls the purchase of all imported feed ingredients and the prices at which they are sold to the feed industry. The agency also controls the prices of home-produced ingredients as well as the prices of manufactured products. Profit margins of manufactured feeds are low.
There is still excess capacity within the milling industry, largely because of recent new mill constructions. Together with the Government's willingness to import large quantities of raw materials to support increases in domestic meat production, the feed industry is capable of producing compounded fish feed in such quantities as to meet the needs for achieving aquaculture production targets set by the Government.
Nepal
There are no official statistics on the production and demand of compound feed in Nepal, but given the low demand for red meat, the figures must be quite low. The largest privately owned mill operated by Ratna Feeds is located in Kathmandu. It produced 15 t of mixed feed a day during the time this survey was made in 1979. The bulk of production (80 percent) went to poultry feed and the remainder to cattle and other livestock. No fish feed was being manufactured. The Company was in the process of going into pelleted feed production using machinery made in India. A Government-owned commercial mill at Hetauda produced 6 to 10 t of mixed feed a day. Cattle feed constituted 60 percent of this mill's products, with the balance made up of feed for poultry, pigs and fish. Fish feed produced by this mill was in mash form.
Nigeria
Feed manufacturing in Nigeria is still at a very early stage of development. There are fewer than 24 mills throughout the country. Half of these are under the control Of an American pharmaceutical company that initially provided financial support for their construction in order to create demand for their proprietary products, especially feed supplements. Other mills are owned by private British and Nigerian interests. At least one mill in the eastern part of the country is owned by the State Government. There are no official figures on annual production of compound feed in Nigeria. Based on estimated feed grain consumption by the mills, 300 000 t were said to be produced in 1979, most of it for poultry. The growth rate of the industry during the preceding years had averaged an impressive 25 percent/annum. There is no commercial production of compounded fish feed.
The industry relies heavily on imported raw materials. These range from feed grains, such as maize and sorghum, to protein supplements including soyabean meal and fish meal. Cereal by-products - wheat bran and rice bran - from local mills and residues from the oil extraction industry - groundnut oilcake, soyabean meal and cottonseed cake - constitute the major raw materials available locally. However, supplies of these ingredients are insufficient to meet requirements of the industry. Soyabean meal and groundnut oilcake have to be imported from abroad to make up the deficiency.
One privately owned mill (Desba Feeds) situated in Port Harcourt was producing only poultry feed. Machineries for this mill were imported and consisted of a 1-t vertical mixer and a 30-HP hammer mill. The mill was of recent construction and was operating on one shift, producing about 10 t of mash-type feed per day. Practically all production was for poultry.
The industry is also constrained by a shortage of qualified manpower. Newer technology such as that used in pelleted feed manufacture is still quite uncommon in the industry. Coupled with the absence of commercial demand for fish feed, any development in fish feed manufacture will have to depend on the initiative of Government research institutions.
The Philippines
The Philippines is the one country among those surveyed where the fishery industry plays a more important role in supplying animal protein than the livestock industry. However, the country's feed manufacturing industry more closely reflects developments in the poultry and livestock industries since production of compound fish feed is insignificant. There are more than 80 feed mills registered with the Bureau of Animal Industry. Nearly half of them are located in Metro Manila. The capacities of these mills vary. The largest mill, situated in Metro Manila, has an annual output of 250 000 t, and the five largest account for 40 percent of the total production nationwide. The feed industry's share of the total market for feeds in 1980 was 2 million t, representing approximately 60 percent of total feed consumption for that year. Seventy-five percent of industrial feeds was for poultry, the remainder for pigs. Growth of the industry during the last five years, at 10 percent per annum, had been average among the countries surveyed.
Feed production is based primarily on locally available ingredients. Chief among these are: maize, rice bran, copra meal, soyabean meal, meat meal and cane molasses. However, the industry is increasingly dependent on importation for its supplies of fish meal, meat meal and soyabean meal.
The enactment in 1972 of several legislations governing the production and marketing of feedstuffs has contributed to greater sophistication in the feed industry. Machineries installed in the larger mills are modern and are capable of manufacturing pelleted fish feed. Such a demand, however, has not arisen because the bulk of fish cultured in the country are milkfish which are fed primarily on algae.
Sri Lanka
After a severe set-back due to the collapse of the poultry industry in 1973, production of compound animal feed continued to make progressive recovery during the last two years. Although production has not quite returned to 1972 levels, when 120 000 t were estimated to have been produced, the largest Government-owned Ceylon Oil and Fats Corporation mill at Seeduwa was operating once more at full capacity (triple shift), producing more than 250 t/day, or, at an annual rate of more than 60 000 t.
The feed industry has been developed around two primary crops - rice and coconut. Both rice bran and copra meal (poonac) are available in relative abundance. Although there is a sizable catch of silver bellies (Leiognathus sp.) from which fish meal could be made, its exploitation is very limited due to the lack of an efficient fish reduction industry. Consequently, most of the protein feed such as fish meal, meat meal and soyabean meal is imported. The Seeduwa mill used the following ingredients for manufacture of poultry feed: poonac, rice bran, dried fish, meat meal, soyabean meal, maize, sorghum, damaged paddy, wheat flour, dhal, lentils and pulses.
Product quality is hampered by periodic scarcity of imported ingredients. Although the Seeduwa mill is of fairly recent design, it is not equipped for pelleted feed manufacture.
Thailand
The Thai feed milling industry is one of that country's largest and fastest growing industries. Of the 60 or so registered feed mills, nine large, integrated mills account for more than half the 3 million t of improved feed manufactured annually. Feed for poultry make up 60 percent of this production, and the balance is primarily for pigs. Less than 10 000 t of fish feed were manufactured in 1981. Factory manufactured feeds, however, represent only one-quarter of the total feed requirements for farm animal production. The balance, mainly for pigs, but also for poultry and fish, is met by on-farm mixing by the farmers themselves. Nevertheless, the feed milling industry plays a prominent role in the operation of the modern farm and, by its own involvement in commercial livestock production, has fostered high quality standards for factory-manufactured feeds.
The industry is supported by Thailand's abundance of diverse feed raw materials. The principal ones used in compound feed manufacture are: maize, sorghum, cassava meal, fish meal, soyabean meal, kapok seed meal, kathin and molasses. Quantities of meat meal and soyabean meal have to be imported from time to time when export pressures on domestically produced fish meal create shortages and drive up prices for that commodity.
The industry has generally kept up with the latest developments in milling technology. The major mills are fully automatic and integrated, with at least one mill having a designed capacity for producing 40 t of pelleted feed per hour. Although commercial, sinking-type pelleted feeds for Clarias culture were introduced ten years ago, their high cost at that time made their use uneconomical. Since then, rising cost and diminishing supplies of trash fish (the traditional feed for Clarias culture), together with increased fish health problems associated with its use, have revived fish farmers' interest in factory manufactured dry feeds. The result has been the introduction, two years ago, of a floating-type, dry, pelleted feed, employing extrusion technology. Feed conversions as low as 1.3 have been claimed with this type of feed, but comparatively higher cost has resulted in its slow acceptance by fish farmers. Unless less expensive formulations based on indigenous ingredients are developed, farmers will find such products uneconomical to use.
Venezuela
Venezuela has a sophisticated and well organized animal feed manufacturing industry that dates back more than 20 years. In 1979 there were more than 30 mills throughout the country. Of these, 18 were members of the national feed manufacturers' association (AFACA) which accounted for 75 percent of the total output of 2.5 million tonnes of compound feed used in the country. Five companies operating 8 modern mills dominated the industry with an estimated production of 1.7 million tonnes. The largest, Protinal, had a 30 percent share, or 700 000 tonnes. Since 1977, the industry had been growing at a rate of 7 percent/year.
The main product line was poultry food accounting for about 60 percent of the total market, and divided equally between boilers and layers. Of the balance, pig foods accounted for 30 percent, and cattle (mostly dairy) and pet foods shared the remaining 10 percent. A large percentage, about 30 percent, of the production was delivered in bulk to big, mechanized farms. Although Protinal had been marketing a commercial trout feed 1/ for some years, annual production of fish feed was small.
1/ A trout diet, marketed under the Protinal brand name of 'Trucherina' had the following guaranteed analysis:
|
Crude protein, min. |
50% |
|
Crude fat, min. |
2% |
|
Crude fibre, max. |
5% |
|
Nitrogen-free extract, min. |
16% |
Ingredients used included: fish meal, soyabean meal, meat meal, processed cereals, minerals and vitamins. The diet was specified as balanced and was meant for use in complete feeding of trout for all age classes.
The principal ingredients used by the industry included: maize, sorghum, wheat bran, maize gluten, cottonseed meal, groundnut meal, sesame meal, soyabean meal, fish meal, meat meal, feather meal, and alfalfa meal. Trade in many of these ingredients comes under the regulation of the Government farm marketing agency CORPOMERCADEO (CMA). The Agency controls the supply and price of both imported and home-grown feed commodities. Feed manufacturers first estimate their future raw material requirements through AFACA. This information is relayed at quarterly meetings with CMA which then decides on the split between home production and imports. Tenders are then invited in international markets to meet import requirements.
As a result of Government price regulation, the industry has been able to maintain a more or less constant rate of return on capital. In the year of the survey (1980), profitability was estimated at 15 percent on capital employed, and 2.5 percent on turnover.
Product quality is generally good due to the country's relatively high level of development in the livestock sector and the advanced technology employed by the feed industry. Presently, the only commercially available fish feed is for trout.
It is widely recognized in the feed manufacturing industry that steam conditioning is of vital importance in pelleted feed production. The use of steam
(i) increases pellet press outputs and reduces die wear;
(ii) improves pellet hardness and durability; and
(iii) increases the nutritional value of the feed.
Under normal operating conditions involving a single horizontal barrel-type steam conditioner, mash transit time is brief - between 5 and 20 seconds. During this short period, liquids such as molasses or fats that are added may not be absorbed sufficiently to prevent their interference with the subsequent pelleting process. Excess water (from added molasses) may "choke" up the die causing interruption in pellet production. Excess unabsorbed fat results in production of soft pellets with low durability.
To overcome these effects, recent developments have centred on providing greater retention time of feed that include high levels of added liquids in the conditioner. Two new processes have been proposed (Carmichael, R.Q., 1981). One describes a long term conditioning process involving retention of feeds in a ripening kettle. The other, which is still in a developmental stage, involves double pelleting with intermediate ripening of feed. Pellets produced by the two new processes are said to be of higher quality than by the standard process.
Feed cost represents 40 to 60 percent of total operating cost in intensive aqua-culture. For a fish farm to be profitable, feed cost should not exceed 20 percent of the farm-gate value of the product if the feed used is the dry type, and not more than 10 percent if moist type pellets are employed. Typically, a ton of dry pelleted feed, based on conventional ingredients, in a developing country that relies upon imports for most of its supplies of feed protein supplements ranges from US$ 300 to US$ 400, depending upon its protein content. To this must be added:
(a) manufacturing cost. This can vary from US$ 5 to US$ 10 per ton depending on energy cost, which accounts for 70 percent of total manufacturing cost;(b) marketing expenses. Normally this represents about 1 percent of the product value; and
(c) operating margin. Generally speaking, feed manufacturing is a high-volume, low-margin business. Margins as low as 2 percent are not uncommon.
The cost to the farmer, then, ranges from US$ 320 for a ton of 27 percent protein feed for tilapia and carp to US$ 425 for one that contains 40 percent protein for trout. At these prices, the farmer breaks even if tilapia and carp fetch US$ 1.60/kg and trout US$ 2.13, at the farm gate 1/. Current prices for these fishes, especially for trout, in most countries are considerably higher, indicating the feasibility of employing industrial feeds for their production.
1/ Assuming that feed conversion for both trout and the warm water species, on their respective feeds, are similar.
