Eimeria tenella oocyst shedding and output in cecal or fecal contents following experimental challenge in broilers

Abstract

Two experiments were conducted to determine whether Eimeria tenella oocyst output in cecal and fecal contents, lesion development, and performance characteristics were affected by ad libitum versus restricted feeding and challenge level. In experiment 1, 144 Cobb 500 males were placed in battery cages with 6 chicks/pen. On d 20, half of the battery pens were placed on feed restriction and all broilers were orally challenged with Eimeria tenella oocysts at one of 3 challenge levels (0, 5,000, or 20,000 sporulated oocysts). Cecal and fecal material were collected separately from d 4 postchallenge through d 10 postchallenge for oocysts output (oocysts shed/g) determination. Six days postchallenge, 3 broilers from each pen were removed and subjected to necropsy for lesion assessment. In experiment 2, 96 Cobb 500 males were placed in identical battery pens with 8 chicks/pen. On d 14, restricted feeding was initiated and broilers were challenged with Eimeria tenella oocysts at one of 3 challenge levels (1,000, 5,000, or 20,000 oocysts). Twenty-four hour collections of cecal and fecal material were obtained separately from d 4 postchallenge through d 10 postchallenge for oocysts per gram and total output determination. Six days postchallenge, 4 broilers from each pen were removed and subjected to necropsy for lesion assessment. In both experiments, BW gain was not affected by challenge dose in either the ad libitum-fed or restrict-fed broilers. Increased lesion development was observed with increasing challenge levels, and oocyst shedding peaked between d 7 and 9 postchallenge in both experiments. Oocyst concentration was higher in cecal droppings compared with fecal material throughout peak shedding; however, total oocyst output for the challenge period was similar between fecal material and cecal droppings.

Assessment of the protective effect of Artemisia herba-alba Asso against Eimeria tenella induced coccidiosis in broilers

“…To prove their effectiveness, several test parameters are commonly utilized in research. Oocyst shedding is a useful way to determine the level of Eimeria infection (Jordan et al, 2011). Quantification of OPG provides information at the infection level and reproduction of Eimeria, which may be used to monitor treatment impact on the overall Eimeria life cycle (Chasser et al, 2020).…”

Anticoccidial effect of Origanum majoranum aqueous extract on Eimeria tenella-infected chicken

“…E. tenella specifically infect the ceca in chicken (Zhou et al, 2020). E. tenella infection is followed by bloody diarrhea, reduced weight gain, high morbidity, mortality and cecal lesions (petechiae, thickening, ecchymosis, accumulation of bloody caseous material in the cecum) (Jordan et al, 2011;Macdonald et al, 2019). For long time, Eimeria infections have been controlled using anticoccidial drugs, but, extensive and continuing usage of such drugs has led to worldwide progress of drug resistance and the public is becoming more conscious for the harmful effects of drug remains in poultry products (Peek & Landman, 2011).…”

<i>Eimeria tenella</i> oocyst excretion and riboflavin supplement in infected chicken

“…E. tenella, E. acervulina, E. maxima , and E. necatrix are the four major pathogenic species [ 1 ]. E. tenella infection causes a severe disease characterized by bleeding, hemorrhagic lesion development, mortality, and reduced weight gain [ 7 ]. Coccidia damage epithelial cells of the intestine and hinder the absorption of nutrients or production of the vitamins indispensable for the chicken’s metabolism [ 13 ].…”

“…This might be because after the ingestion of the sporulated oocysts, the sporozoites are released and penetrate into the intestinal epithelial cells. Then, the sporozoites transform into merozoites, which multiply asexually [ 7 , 9 ]. During asexual stage, bloody diarrhea occurred due to the destruction of epithelial cells by the merozoites.…”

“…During asexual stage, bloody diarrhea occurred due to the destruction of epithelial cells by the merozoites. This is followed by the sexual stage and continuous oocysts excretion [ 7 ]. The OPG of the riboflavin-treated group was higher than the positive control group; the former being 2.63 × 10 5 and the latter 5.63 × 10 4 .…”