Coccidiosis, poultry

Coccidiosis is a proto2oal disease of the intestinal tract of animals that leads to severe loss of productivity and death. The development and widespread use of anticoccidials has revolutionized the poultry industry. The estimated world market for anticoccidial agents in 1989 was 425 million and this was dominated by the polyether ionophore antibiotics monensin, salinomycin [53003-10-4], n imsm [55134-13-9], la.s9locid, and maduramicin [84878-61-5] (26). 

Anticoccidial Activity. The 1968 report that claimed monensin has activity against Eimeria sp., particularly E. tenella E. macdma., and E. acervulina greatly altered the prevention and control of coccidiosis in poultry (172). It is estimated that the polyether ionophores presently constitute more than 80% of the total worldwide usage of anticoccidials (173). Lasalocid and monensin have been approved for use in control of coccidiosis in cattle. 

Table 3 Hsts the polyether antibiotics used as poultry anticoccidial dmgs in the United States. Recendy, lasalocid and monensin have been approved for use in bovine coccidiosis at levels in feed of 11—33 g/t.

Arsonic and arsinic acids have found a number of industrial uses. They have been used as corrosion inhibitors for iron and steel, additives to motor fuel, agricultural bactericides, herbicides, and fungicides. 3-Nitro-4-hydroxyphenylarsonic acid (roxarsone) [121 -19-7] C H AsNOg, has found widespread use as an additive to poultry feed for the control of coccidiosis and other poultry diseases (122,123). Arsanilic acid [98-50-0] C HgAsNO, has also been used for this purpose (124) and for growth promotion in swine. It is manufactured and suppHed by Duphar Nutrition Co., Inc., Fleming Laboratories, Inc., Dr. Mayfield Laboratories, Inc., and Whitmoyer Laboratories, Inc. 4-Nitrophenylarsonic acid [98-72-6] C H AsNO and... 

Diaveridine (1044) is a close relative of trimethoprim (Section 2.13.4.2.3) and is made by an analogous Principal Synthesis. It is used prophylactically against coccidiosis in poultry and in combination with sulfaquinoxaline as a curative agent for the same disease similar mixtures are also effective (64MI21305). 

Some of these compounds could be considered as dietary additives, but various other terms, including pesticides, can also be used. They can have beneficial effects on the environment and this aspect will be discussed later. The ionophore monensin, which is an alicyclic polyether (Figure 1), is a secondary metabolite of Streptomyces and aids the prevention of coccidiosis in poultry. Monensin is used as a growth promoter in cattle and also to decrease methane production, but it is toxic to equine animals. " Its ability to act as an ionophore is dependent on its cyclic chelating effect on metal ions. ° The hormones bovine somatotropin (BST) and porcine somatotropin (PST), both of which are polypeptides, occur naturally in lactating cattle and pigs, respectively, but can also be produced synthetically using recombinant DNA methods and administered to such animals in order to increase milk yields and lean meat production. "... 

The nature of the conditions of intensive production, however, can increase the risk of diseases and infections which can spread very rapidly and devastate large numbers of animals." Thus it is common practice for producers of poultry to add coccidiostats to their diets and vaccines to their drinking water in order to prevent coccidiosis and other infectious diseases such as bronchitis and Newcastle disease. A similar problem exists for intensively reared fish, where it is necessary to add antibiotics to their diets. A problem with intensively reared fish is that their diet is added directly into the water in which they live thus drugs and other additives in the diet are relatively easily dispersed into the local environment of fish farms, where they can increase bacterial resistance and also cause problems such as algal blooms. 

Anti-protozoa agents are utilized to treat diseases such as coccidiosis, which affects many farm animals, particularly poultry. Coccidiostats include polyether monocar-boxylic acid ionophores and other types of compounds. Polyether monocarboxylic acid ionophores include monesin, narasin, lasalocid, and salinomycin. The most common of these is salinomycin. Nonionophore coccidiostats include dimetridazole and halofunginone. Stanker et al. reviewed immunoassays available for coccidio-static agents. 

Awkward One of the most common and costly diseases in poultry is coccidiosis. 

Better Coccidiosis is one of the most common and costly diseases in poultry. (Adapted from Peippo et ah, 2004)... 

A compound that includes an aminopyrimidine ring as well as the quaternary salt present in thiamine shows preferential inhibition of absorption of that co-factor by coccidia parasites over uptake by vertebrates. The compound is thus used in poultry where coccidiosis is an economically important disease. Condensation of ethoxymethylenemalononitrile (42-1) with the amidine (42-2) leads to the aminopyrimidine (42-4), probably via the intermediate addition-elimination intermediate (42-3). The nitrile group is then reduced to the methylamino derivative (42-5) by means of hthium aluminum hydride. Exhaustive methylation, for example by reaction with formaldehyde and formic acid, followed by methyl iodide leads to the quaternary methiodide (42-6). The quaternary salt is then displaced by bromine, and the resulting benzyhc-like cylic halide (42-7) is displaced by 2-picoline (42-8). There is thus obtained amprolium (42-9) [43]. 

Furaltadone has been used primarily for treatment of poultry infected with salmonellosis, colibacillosis, coccidiosis, blackhead, and infectious synovitis at a dosage of 0.02-0.04% in the drinking water or feed for a maximum of 10 days. The drug has been also used in intramammary form to treat bovine mastitis at a dosage of 500 mg/quarter. 

They are still widely used as feed additives for treatment or prevention of coccidiosis. In ruminants, sulfaquinoxaline, sulfadimethoxine, and sulfame-thoxypyridazine are the most useful coccidiostats, although sulfachlorpyrazine, sulfathiazole, and sulfamonomethoxine are also highly effective. Additional coccidiostats or adjuvants such as amprolium, chlortetracycline, and ethopabate are often combined with sulfonamides for synergistic effects in poultry. 

Sulfadimethoxine is a low-dose, rapidly absorbed, long-acting sulfonamide that is effective in reducing mortality due to bacterial infections and coccidiosis in poultry and ruminants (212, 213). The drug is highly protein-bound (80-85%) and this probably contributes to its slow excretion. 

Monensin plays a dual role in veterinary practice because it is used both as a coccidiostat in poultry and as a growth promotant in cattle. It is also efficacious in the control of coccidiosis in lambs and calves, can treat ketosis in dairy cows, and can control bloat in pastured dairy cattle. It is administered incorporated in poultry feeds as a coccidiostat at a dose up to 120 ppm, and in cattle and sheep feeds at a dose of 11-33 ppm. Monensin is not recommended for administration to laying hens, while a 3 day withdrawal period is required for chicken meat. 

Lasalocid is widely used for controlling poultry coccidiosis since it is very efficient against all species of Eimeria at the optimal dose of 90 ppm in the feed. It is licensed for use in broilers and hens up to 16 weeks from hatching but is not licensed for use in laying hens. It has been also used as a growth promoter in cattle. 

Coccidia are intracellular protazoal parasites that are frequently found in the intestinal epithelial cells of animals they are also found in other tissues (liver), and are usually transmitted by faecal infection. The potential for infection is at its highest when young animals are brought together in intensive housing systems (e.g. poultry-broiler production). As a result coccidiosis is a major issue for the poultry industry throughout the world. 

Most of the iron in the body is in the form of haemoglobin in red blood cells and myoglobin in muscle. The remainder is in the liver, spleen and other tissues. Haemoglobin is essential for the proper functioning of every organ and tissue of the body. Iron has a rapid turnover rate in the chicken therefore, it must be provided in a highly available form in the diet on a daily basis. Iron deficiency can result in microcytic, hypochromic anaemia in poultry. Any internal infection such as coccidiosis can also interfere with iron absorption and lead to a deficiency. 

Cumming, R.B. (1992) The biological control of coccidiosis by choice feeding. Proceedings of 19th World s Poultry Congress, Vol 2. Amsterdam, The Netherlands, 20-24 September 1992, 425-428. 

Cumming, R.B. (1989) Further studies on the dietary manipulation of coccidiosis. Australian Poultry Science Symposium, University of Sydney, Sydney, Australia, pp. 96. 

My final topic on in-feed agents is a major problem in the broiler industry. Coccidiosis is a protozoan disease of poultry caused by various Eimeria spp. It is highly prevalent in the intensive rearing conditions common in North America and Western Europe. In fact, such intensive rearing would not be possible without effective anticoccidials. 

Sulfonamides have been used as coccidiostats in poultry for several decades. Although sulfonamides possess inhibitory action against coccidiosis and other pathogenic agents, they can be toxic and have particularly been shown to be so to poultry. In poultry, sulfonamide toxicity is characterized by blood dyscrasia and renal and liver dysfunctions. Feeding chickens a mash containing as low as 0.2% sulfonamides for 2 weeks is toxic. 

The poultry industry employs the sulfonamides sulfaquinoxaline (114), also known as Diamprim, and sulfadimidine (115) for treatment of coccidiosis. The antimalarial pyrimethamine (116) (see Chapter 1) exhibits anti-coccidial properties, as does amprolium, APL, l-[(4-amino-2-propyl-5-pyrimidinyl)methyl]-2-methylpyridinium chloride hydrochloride (116a), a thiamine antagonist73. 

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