Development of Immunity to Coccidiosis in Chickens Administered Anticoccidials in Feed

Abstract

New combinations of techniques were employed for comparing the development of immunity of Eimeria tenella in chickens being medicated with 12 different anticoccidials. Broiler-type birds in batteries received a daily measured dose of E. tenella oocysts for 15 consecutive days while the drug was administered at the manufacturer's recommended level. Two or more tests of each drug gave the following ratings: strong suppression, monensin (121 ppm), salinomycin (80 ppm), lasalocid (75 ppm); moderate suppression, monensin (100 ppm), decoquinate (30 ppm), clopidol (125 ppm), and narasin (80 ppm); slight suppression, arprinocid (70 ppm), nicarbazin (125 ppm), and amprolium (125 ppm + ethopabate (4 ppm); no effect, robenidine (33 ppm), zoalene (125 ppm), and aklomide (250 ppm).

Anticoccidial drugs and their effects upon the development of immunity toEimeriainfections in poultry

“…Thus, with buquinolate, little or no immunity to a mixture of different species had developed by 9 weeks (Edgar & Flanagan, 1968), but, in another study, birds developed resistance to E. tenella, E. necatrix and Eimeria brunetti but not Eimeria maxima, Eimeria mivati and E. acervulina by 8 weeks of age (Reid et al, 1968). In the case of clopidol, immunity was prevented in some experiments (Karlsson & Reid, 1978) but not in others (Reid et al, 1968). Quinolones (such as methyl benzoquate) and clopidol have a coccidiostatic mode of action and arrest development of the sporozoite following penetration of the host cell.…”

“…In some cases, immunity was considered to be`delayed' or retarded' by drugs, even though the actual timing of the acquisition of immunity was not measured (Reid et al, 1977). In a subsequent study, an arbitrary scale (from 0 to 3) was developed to measure the response of birds to challenge; 0 5 complete suppression of immunity, 1 5 moderate suppression, 2 5 slight suppression, and 3 5 no suppression (Karlsson & Reid, 1978). The scale was used to compare results for various drugs in different experiments.…”

“…Many of the older synthetic drugs did not completely prevent parasite development and were not fully effective against all species of Eimeria. Aklomide, amprolium, arprinocid, dinitolmide, glycarbylamide, nicarbazin, nitrofurazone, nitrophenide, Polystat, robenidine, trithiadol and zoalene were reported not to prevent immunity developing to various species HortonSmith & Long, 1952;Gardiner & Farr, 1954;Berg et al, 1956;Cuckler & Malanga, 1956;Edgar, 1958;McLoughlin & Gardiner, 1962;Karlsson & Reid, 1978). In the case of amprolium and nicarbazin, not all results were in agreement since several studies suggested that they either delayed or prevented the development of resistance against reinfection (Strout et al, 1958;McDougald & Reid, 1971).…”

Intestinal absorption following challenge of immune chicks withEimeria acer vulina

“…Although it would be logical to expect immunity to confer protection against the malabsorption effects of coccidiosis, this has not been documented. Karlsson and Reid (1978) have shown that anticoccidials do not allow development of equal degrees of immunity, nor do all birds in a house receive equal exposure to oocysts. Thus the degree of immunity of the bird could well correlate with the amount of protection against malabsorption.…”

Anticoccodial protection and development of immunity to Turkey coccidiosis while using monensin

“…Monensin alters oocyst production and may affect immunity development (Karlsson and Reid, 1978). In chickens, 120 ppm of monensin in the feed resulted in a delay in the development of immunity in floor-pen trials (Callender and Shumard, 1973;Reid et al, 1977).…”