Reduced feed costs lead to improved production efficiency and profitability of poultry enterprises. Feeding and management strategies will help in achieving these targets. Farm resources, management policies and mode of production are determining factors.
By Dr Salah H. Esmail, Cairo, Egypt
Broiler chickens are usually fed on an ad lib basis to allow them to get their energy needs and to achieve their target weights in shorter periods of time. In recent years, however, timed feeding of broilers has been recommended for economic reasons. Here, the birds are fed a set amount of feed 4-6 times a day so they finish their meal and are then held without feed for about one hour or less. This has two beneficial aspects. First, it reduces the chance for the mechanical stimulation of feed intake that is often experienced when running the feeders throughout the day. Second, during these times without feed birds are usually quiet, and this may improve feed utilisation due to the reduced maintenance feed requirements.
Manipulation of feed ingredients
Field studies were conducted in Bangladesh to examine the economic impacts of replacing fish meal with broiler offal in broiler diets. Results have shown that inclusion of 8% broiler offal in place of fish meal has decreased feed cost per kg from 53.21 TK (TK stands for Taka, and is equal to about 0.013 US$) with fish meal to 45.77 TK with broiler offal, with the profits per kg being increased from 11.79 TK with fish meal to 19.23 TK with broiler offal.
Other studies conducted at the University of Georgia, US, demonstrated that peanut meal is a perfectly acceptable feed ingredient for laying hens, and could be used at 5% of the diet in place of soybean meal as an attempt to reduce feed costs (US$ 140/tonne for peanut meal vs US$ 225/tonne for soybean meal). The only source of concern about the peanut meal is its possible contamination with aflatoxins. However, when 5% peanut meal is used, the level of aflatoxins in the mixed feed would be much too low to be of practical concern.
Currently, work is underway worldwide to examine the potential of other unconventional feed resources and their impacts on poultry production. Examples of such resources include fly pupae, marine flora, kitchen disposals, poultry litter, fruit and vegetable processing wastes, etc. Although promising results have so far been obtained with most of these feeds, further work is still needed to ascertain their economic feasibility under practical farm conditions.
Use of synthetic amino acids
Protein nutrition has a great economic importance, since protein is an expensive item in almost all feed rations. This may particularly be so in areas of the world known to be protein deficient, such as many tropical and subtropical areas. The rationing of feeds for protein should, therefore, be manipulated in such a way that "optimal" rather than "maximum" performance is achieved without too much feed expenditure. The best way to explain this point is by a practical example of a layer feed with 16% or 17% protein. In corn-soybean diets, this difference can be created by adding 3% more soybean containing 44% crude protein. When this amount replaces corn, there will be an additional cost of about US$ 3.00/tonne (world market price). In most cases, the real nutritional benefit of such an increase of protein is limited to an increase of about 0.025% of the amino acids lysine and methionine. The same nutritional advantage can be obtained by adding 250 g of synthetic lysine and methionine/tonne of feed with a cost of only US$ 1.00/tonne. Fortunately, access to these synthetic amino acids has become available with the recent advancement of biotechnology, which makes the economic benefits of such an approach quite achievable.
Control of feed wastage
In many cases, high feed consumption or any of the other related aspects may not solely be descriptive of a problem. There are many other routes through which feed is wasted or lost without even getting into the bird. These alone could amount to as much as 5 g/bird/ day or even more, depending on farm conditions and management.
1 - Feed troughs
In many poultry farms, especially in the private sector, birds are typically fed through elongated troughs made of galvanised metal sheets. These are preferred by farmers, because of their availability in the market, low costs, and high resistance to physical damage, but feed wastage can be a severe problem. This problem could, however, be alleviated by replacing galvanised troughs with pan or chain feeding system. In a survey conducted in Egypt, it was estimated that with a broiler house of 10,000 birds, at least two tonnes of feed will be saved during each production cycle. With feed costing E£ 1,000-1,050/t and six production cycles a year, the cost of the new feeding system could be recouped in 18 months.
2 - Adjusting feed level in the feeders
Overfilling of feeders should always be avoided, and feed should be maintained at certain levels to minimise losses (Table 1).
3 - Beak trimming
Long beaks give the birds the ability to play with the feed which cannot then be consumed once it reaches the floor and get mixed with the bedding materials. Proper beak trimming is, therefore, essential to alleviate much of this problem, in addition to the other advantages of alleviating cannibalism and other vicious habits. Results of beak trimming effects on feed wastage and on feed utilisation are given in Table 2. These results, however, may vary greatly depending on such variables as age when beaks are trimmed, type of cut, severity of trimming, temperature of the cauterising blades, and so on.
4 - Rodent control
Rodent infestation of poultry farms is a common problem interfering with feed utilisation. A 250 gram rat can eat its own weight in a day (about 90 kg/rat/year). This means that a farm with a total population of 50 rats, for example, could simply lose tonnes of feed each year, unless such a problem is strictly eliminated from the start.
5 - Feed spoilage
Spoilage of feed and mould growth are also contributory factors to feed waste and loss. These problems are most prevalent in feeds that are not appropriately processed. They are also prevalent in tropical regions where the hot, humid climate favours growth of mould on feed.
A compound called sodium calcium alumino-silicate is effective in controlling spoilage and mould damage of feed, and could safely be used at 0.5% without any detrimental effects on poultry. Also, the use of feed silos may help alleviate the spoilage problem, and also protect feeds against invasion by rodents or wild birds.
From an economic standpoint, the cost of a 20-tonne silo (about US$ 6,000) could be recovered in just two years, as it could save up to US$ 2,000-3,000, being the value of feed that could be lost each year through other feed storage systems. Additional savings could be achieved with regular cleaning and proper maintenance of the silos, and also with the use of antioxidants and other preservatives throughout the production cycle.
Enzymes play an important role in enhancing feed utilisation and reducing feed cost. Phytase, for example, is a proven technology used to release some of the non-digestible phosphorus and reduce excretion of this element, thereby reducing the cost of inorganic phosphorus supplementation. Protease, on the other hand, is effective in releasing protein anti-nutrients found in some feed ingredients such as soybean, thereby making dietary protein more available. When other enzymes such as amylase and xylanase are incorporated into the diet, there would be around a 3-5% increase in the feed energy available to the bird. Typically, enzyme supplementation costs around $1.5 per tonne of feed, but feed costs can be reduced by $2.5 per tonne in low energy layer diets to over $4.0 per tonne in high energy turkey diets.
Use of flavours
The effects of feed flavours on weight gain and feed conversion by broiler chickens have been tested in four experiments. The combined results of these experiments indicated that the birds receiving flavoured feed averaged 8 grams heavier than the control birds at four weeks of age, and 3 grams at eight weeks, with combined improvements in feed conversion of 6.2% and 3.0% at four weeks and eight weeks of age, respectively. Such improvements in feed conversion have resulted in a saving of 3 tonnes of feed for 0.4 kg of gain per bird for 50,000 broilers at four weeks of age. At eight weeks, the saving in feed for 1.3 kg of gain per bird for 50,000 broilers would be approximately 4.25 tonnes of feed.
Farmers may suffer a considerable increase in feed costs and losses in egg income because of poor feather cover in winter, mainly due to increased feed consumption at low temperatures. Compared to the fully feathered hens, naked birds can eat 40 g/bird more at 15°C, and 30 g/bird at 18°C.
Reports from Australia have revealed that the increased feed costs arising from such extra feed consumption in this case amounts to $AUS 6.57 million annually, which forces the need for keeping hens warm in winter. However, for this strategy to be viable the heating cost should first be balanced out against the increase in feed cost, and the matter could then be brought into a final conclusion to benefit the farm economy.
The effects of disease on feed utilisation should not be overlooked. It has been estimated that feed efficiency decreased by 25%, 18% and 10% in birds infected with Gumboro, Coccidiosis and Salmonella, respectively. Similar responses may also be expected with nutritional or parasitic diseases. Effective veterinary programmes should, therefore, be considered in all these cases for better health, performance, and revenues.
References are available from the author upon request.