INTRODUCTION
1.1 Background of the study
Poultry are collection of birds raised commercially or domestically for meat, egg and feathers. Chickens, ducks turkeys and geese are of primary importance while guinea fowl and squabs (pigeons) are chiefly of local interest. These birds are source of income and food to the rarer. In the past only hens that could no longer produce eggs were killed and sold for meat but by the mid-20th century, meat production had outstripped egg. Production as a specialized industry (Encycloparredia Britaimca, 1988). Heavy breed poultry animals are used for meat white light bread chickens are primarily for the production of eggs (Mc Graw Hill encydopaedia 1992). The meat and eggs produced from poultry are important sources of dietary portion. In Africa, animal protein foods from all sources contribute between 7g and 15g daily per person to the total food intake (Oyenyga, 1974). Today, Poultry production in the country is increasing at a tremendous rate and yet cannot meet the demand because of population growth and the awareness created by the campaigns for the need of animal protein in the diet.
The growth and well-being of organisms are to a large extent dependent on the mount and type of food they receive and the manner or rate at which they receive it. The food should contain nutrients such as water, carbohydrates, fats, protein, minerals, vitamins and added growth factors improper balance. Each of these nutrients has a major role to play concerning growth, maintenance and productivity of the poultry. According to Leonard 91981), nutritional deficiency or inbalance. These diseases may include rickets, perosis, and nutritional roup, curly the paralysis etc. These diseases could result due to deficiency in vitamins D, Manganese, vitamin A, vitamin E and riboflavin. Improper sanitation and inadequate management play major roles in disease. Outbreak and productivity of the desired products. In developing countries like Nigeria, the cost of feeding, especially the monogastries continues to escalate primarily in response the soaring cost of the conventional feed ingredients. This phenomenon is precipitated by under production and importation of some food stuff coupled with the competition between man and farm animal for energy and protein concentrates.
The use of agro-industrial by-products towards reducing food cost has been widely recognized (EshieH and Ademosun, 1981; Atteh and Oloagbenla, 1993). Chicken and turkeys satisfy their energy needs provided the ration a allows them to do so (Church, 1988). The are of course exceptional to this rule particularly where heavy breed layers are concerned, when birds have a tendency to over-eat. Where this is a problem, it is general practice to subject the birds to some degree of food restriction during the growing and production periods. The major ingredients that are integral parts of poultry rations at the present time in the USA are corn, as the primary source of energy and soybean meal as the major protein supplement (Roland et al 1972), while in Nigeria, Udedibie et al (1988) and Nwokon (1993) produced poultry offal meal (P.O.M) and chicken offal meal (COM) respectively from waste product similar to poultry visceral Offal (PVO) according to these authors POM has been used to replace ground nut cake in layer and broiler finisher diets and COM has been used along with fish meat and blood meat as sources of methodize and lysine in the starter diets of lockerels. These major ingredients, usually available in plentiful supply, allow rapid growth or high egg production with very efficient conversion. However, corn-soy rations are deficient in some nutrients for chickens and these nutrients are normally supplied by other poultry meal.
There are different types of feeds given to poultry brids depending on the purpose. These different types of feeds given to poultry birds depending on the purpose. These different types are the breeders’ starters, growers’ and layer’ feeds. The percentage of each ingredient in the feed varies depending on the type of feed. The ingredient include ground yellow corn, ground oats or barley, Alfata meat, Fish meal, Oystershell, managised salt, vitamin A, vitamin D, and coccidiostat (which is given in form and at the level recommended by the manufacturer). The different percentage of each ingredient varies depending on the kind of feed for example, ground yellow corn in starter and grower feed is 25% and 22% in breeder and layer feeds. There could be the same percentage of a particular ingredient in different feeds as in the case of a alfafa meal which constitutes 10% inall the feed types. Some ingredients could be absent in a particular feed but present in the others as in the case of riboflavin supplement which is absent in starter feed and present at the levels of 2 and 5% in rower, layer and breeder feeds respectively.
To maintain healthy birds, the feeds are kept fresh as much as possible at all times. The amount of feed in feeders are limited to the extent necessary to avoid wastage. It is a good practice to fill hanging feeders – only three quarter full, and trough feeders only two third full (Graham, 1977). Checking the weight of the birds and its feed consumption is very necessary. A drop in feed intake usually is the first indication of trouble, a disease outbreak, molt, stress or poor management (Graham, 1977). Most poultry feed are prepared in dehydrated forms and because of this, there is the need to store them properly to avoid moisture uptake and damage by heat. In this way,. They can remain safe for a considerable period of time without loosing their safeness and value. The feed should be stored in a suitable place where it will not be attacked by microorganisms, insects, rodents, etc. Air tight storage is not advisable because offensive odour might result when there is obstruction of out flow and inflow of air (Leonard, 1981). High temperature and oxidation destroy certain vitamins, therefore, care must be taken in the preservation and storage of feeds to protect the vitamins they contain (Mc Graw – Hill encyclopaedia 1992). The condition of feed storage and handling could be a source of contamination. When feeds are unhygienically handled and stored, there could be a buildup of microbial contaminants.
Poultry have been found to be susceptible to infection due to certain microorganisms and man may be secondarily infected through heavy contaminated food such as poultry meat and eggs (Gorden and Tucker, 1965, Hall, 1977, and Barrell, 1982). Micro-organism that may contaminate feed include the following general another disease caused by salmonella infections is paratyphoid. Paratyphoid is an infection disease of chi, Entherobacter, Escherichia, Protens, Pseudomonas, staphylococcus, salmonella, shigella, providencia, serratia, Klebsiella,streptococcus, clostridium, Aspergillus and Erysiphelothrie (Leonard, 1981). Typically, in some countries, about 50% of all outbreaks of salmonellosis in man are caused by infections derived from these sources and the incidence of salmonella in poultry carcasses has, in certain cases been found to be 7% or more (Van schothorst Notermans, 1980). Okongi (1984) examined poultry feed and found that salmonella was present in the sample. Another disease caused by salmonella infections is paratyphoid, Paratyphoid is an infections disease of chicken, turkeys, ducks and other birds. Bofulism another kind of disease occurs in both young and adult poultry birds. It is caused by a bacterium, Clostridium Botulinum. This organism grows in decaying plants and animals materials. Birds feeding material containing the toxins produced by the bacteria lose control of their neck muscle (Leonard, 1981).
1.2 Statement of problem
Poultry feed is known to contain salmonella, and other microorganisms are also implicated in poultry feeds, (Klinger and Ladidot, 1993). It is therefore pertinent to carry out microbiological examination of commercially prepared poultry feeds to ascertain their safety to livestock.
The presence of moulds and mycotoxins in poultry feeds are usually from the raw materials used in their production. Mould and mycotoxin contamination of the raw materials can occur pre-harvest in field produced fungi and post-harvest in store produced fungi (Krnjaja et al., 2008; Davies and Wales, 2010). Feeds may be contaminated by pathogens at any point in the production, storage, preparation processes. Pathogens like Staphylococcus aureus and Escherichia coli have been reported to be transmitted by the feed to susceptible consumers, where they grow and cause diseases, or a food borne infection (Church and Dupont, 1993). Salmonella spp. is the major hazard for microbial contamination of animal feed.