A disease caused by different species of genus Eimeria and characterized by diarrhea , unthriftines , variable morbidity and mortality depend on species causing the disease.

The protozoan parasites of the genus Eimeria multiply in the intestinal tract and cause tissue damage, with resulting interruptionof feeding and digestive processes or nutrient absorption, dehydration, blood loss, loss of skin pigmentation and increased susceptibility to other disease agents

Coccidiosis is a disease of universal importance in poultry production.

Coccidiosis is caused different species of genus Eimeria . These parasites have a predilection site for the development inside the host. The species of coccidia affecting chickens ,turkeys , ducks , geese and pigeons are:

Pigeons Ducks & GeeseTurkeys chicken

•E.labbeana•E.columbarum

•Tyzzeria perniciosa•E.truncata•E . anseris

•E.adenoides•E.Meleagrimitis•E.gallopavonis•E .meleagridis•E .dispersa•E .innocua•E .subrotunda

•E .tenella•E.necatrx•E.acervulia•E .burnetti•E .maxima•E .mivati•E .hagani•E .praecox•E ,mitis

Coccidiosis is generally acute in onset and is characterized by depression, ruffled plumage, and diarrhea. Birds infected with E. tenella show pallor of the comb and wattles and blood-stained cecal droppings.

E. acervulina and E. mivati: 1-2mm areas of hemorrhage interspersed with white foci visible through the serosa of the distal duodenum and proximal jejunum.

E. necatrix: severe distention of the mid-jejunum with hemorrhages in the mucosa and red-stained fluid in the lumen.

E. maxima: distention of the mid-jejunum with hemorrhages in the mucosa.

•.

E. tenella: hemorrhagic typhlitis (inflammation of the

cecum)

E. brunetti: hemorrhages of the mucosa of the distal jejunum and colon. Fibrinonecrotic enteritis may occur in chronic cases.

Drugs are subdivided into:-

Ionophores :-

• lasalocid

• Monensin

• Narasin

• Salinomycin

• Maduramicin

Synthetic chemicals:-

• Amprollum

• Clopidol

• Diclazuril

• Nicarbazine

• Toltrazurile

Combination products:-

• Amprolium+ethapabate

• Narasin+nicarbazin

• Meduramicin+nicarbazin

1. High degree of efficacy against different species of coccidia.

2. Prevent mortality from the parasite.

3. Improve weight and feed conversions.

4. Palatable to birds.

5. Compatability with other drugs and feed ingrediants.

6. Rapid elemination from edible tissues.

7. Stable in mixed feed.

1. Toxic reactions in birds( weights, feed & mortalities).

2. Mottled eggs.

3. Making manure toxic to plants or other.

4. Adverse effects on physiologic processes in birds.

Types of vaccines:-

Non –attenuated vaccines:-

• CCOCIVAC , IMMUNOCOX

Attenuated vaccines:-

• PARACOX

Non -attenuated vaccine:-

Composition:-virulent field strains of EimeriaSPP.

Advantages:-elimination the need for anticoccidial medication , use for several grow outs of these vaccines cause drug sensitive vaccine strains to replace drug resistant strains

Disadvantages :-lack of uniformity of distribution of vaccine , litter management needs to be appropriate for oocyst cycling, short shelf life time of vaccine, more expensive than anticoccidials

Attenuate vaccine:-

Composition:-precocious lines of seven Eimeria SPP.

Advantages:-less pathogenic but as immunogenic as virulent strains.elimination the need for anticoccidial medication , use for several grow outs of these vaccines cause drug sensitive vaccine strains to replace drug resistant strains

Disadvantages :-lack of uniformity of distribution of vaccine , litter management needs to be appropriate for oocyst cycling, short shelf life time of vaccine, more expensive than anticoccidials

Coccidiosis can best be diagnosed from birds killed for immediate necropsy. Attempts to identify characteristic lesions in birds that have been dead for 1 hour or longer are frustrated by the postmortem changes in the intestinal mucosa.

The entire intestinal tract should be examined. A microscope should be available for use in looking for special diagnostic characteristics such as clusters of the large schizonts of E. necatrix or the small round oocysts of E. mitis.

1-Microscopic Examination:.

Developing schizonts, gametocytes, and oocysts of coccidia may be seen in smears taken from the suspected lesion. A small amount of mucosal scraping should be diluted with saline on a slide and then covered with a coverslip.

2-Lesion Scoring:

The severity of lesions is generally proportionate to the number of oocysts ingested by the bird and generally correlates with other parameters such as weight loss and droppings scores. The most commonly used system for lesion score was devised by Johnson and Reid (20). By this system, a score of 0—4 is assigned to a bird where 0 _ normal and 4 _ most severe case.

3-Droppings Score:

. In laboratory infections, the droppings score may be used in the same manner as lesion score for a rapid and fairly reliable rating of the infection .The extent of abnormal droppings is rated on a scale of 0—4, where 4 _ maximum diarrhea, with mucus, fluid, and/or blood. This technique has obvious complications where birds are infected with more than one species ofEimeria.

4-Histopathology Methods:.

Ordinary methods in histopathology are satisfactory for routine examination of tissues infected with coccidia. Staining of sections with H & E or other common histologic stains will demonstrate developing stages. Specialized techniques will identify specific stages: Staining with Schiff ’s reagent gives a brilliant red color with the polysaccharide associated with the refractile body and with wall-forming bodies in the macrogamete. Monoclonal antibodies conjugated with fluorescent markers such as fluorescein are highly useful in research because specific stages of parts of cells can be readily identified.

A –prevention:

1-Preventive anticoccidials approved by FDA for use in feed formulation:

Sulfaquinoxaline, 0.015—0.025% (Merck)

Nitrofurazone, 0.0055% (Hess & Clark; Smith-Kline)

Arsanilic acid or sodium arsanilate, 0.04% for 8 days (

Nicarbazin, 0.0125% (Merck) Nicarb 1955 4

Furazolidone, 0.0055—0.011% (Hess & Clark)

Nitromide, 0.025% _ sulfanitran, 0.03% _ roxarasone, 0.005% (Solvay)

Oxytetracycline, 0.022% (Pfizer)

Amprolium, 0.0125—0.025% (MSD-AGVET

Chlortetracycline, 0.022% (American Aureomycin Zoalene, 0.004—0.0125% (Solvay) Zoamix 1960 (higher levels, 5 days)

Amprolium, 0.0125% _ ethopabate, 0.0004/0.004% (Merck) Amprol Plus, 1963 0

2-New Vaccines to Prevent Coccidiosis:.

The considerable research on coccidiosis vaccines in recent years has produced interesting results, and new products may eventually see widespread use. Along conventional lines, live vaccines have been prepared from attenuated lines of oocysts (e.g., Paracox7 and Livacox7). The success of some vaccines may depend more on a novel administration technique rather than attenuation

3-Disinfection and Sanitation.:

Older recommendations for coccidiosis control often suggest directions for sanitation and disinfection to prevent outbreaks. Most of these are no longer considered valid because 1) there have been too many failures in such programs; 2) oocysts are extremely resistant to common disinfectants; 3) complete house sterilization is never complete; and 4) an oocyststerileenvironment for floor-maintained birds could prevent early establishment of immunity and allow late outbreaks. Chickens reared in cages rarely suffer outbreaks of coccidiosis. The exceptions are usually in single rows of cages in which there has been accidental fecal contamination of feed or water.

1-Control of Coccidiosis by Chemotherapy:

Early emphasis in chemotherapy was centered on the treatment of outbreaks with sulfonamides or other compounds after signs of infection were apparent. Soon, the concept of preventive medication emerged with the realization that most of the damage is done when signs of coccidiosis arewidespread in a flock. Today, almost all broiler flocks receive preventive medication, and treatment is used as a last resort The historical aspects of chemotherapy have been reviewed extensively by McDougald. Consult a current Feed Additives Compendium for up-to-date information on approved products .

2-Programs for Use of Anticoccidial Drugs in Broilers:

In broilers, the objective is usually to produce the maximum growth and feed efficiency with minimum of disease, and in layers or breeders, the objective may be immunization . Continuous Use of a Single Drug. Often, a single product will be used from day 1 to slaughter, or with a withdrawal period of 3—7 days. Most products are approved for use until slaughter, but producers withdraw medication for economic or other reasons.

Thank you !!!