title: Observation of the excretion pattern of a precocious line of Eimeria necatrix and the strengthening of immune homogeneity.
abstract: The excretion frequencies of cecal and intestinal droppings of Chinese Lingnan yellow chickens were observed for 10 consecutive days. The chickens were then orally inoculated with a precocious line of Eimeria necatrix, and the oocysts present in the cecal and intestinal droppings were separately collected and monitored using the McMaster method. The results showed that the excretion frequency of cecal droppings was significantly lower than that of intestinal droppings, and the oocysts of E. necatrix were distributed primarily in the cecal droppings. This distribution affects the homogeneity of the second and third generation of oocysts ingested by the chickens and therefore affects the immune effect observed during E. necatrix immunization. To artificially strengthen the immunologic homogeneity against E. necatrix, a method of artificially strengthening the second immunization was applied, and the immune effect was evaluated based on oocyst excretion, body weight gain, fecal scores, intestinal lesion scores and survival percentages. The results showed that no significant intestinal damage was caused by immunization reactions in the chickens. In addition, the number of excreted oocysts in the immunized chicken groups could be significantly increased, and the immunologic homogeneity of the immunized chickens could be improved by artificially strengthening the second immunization, which could in turn improve the immune protective effect.
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, PR China; Foshan Standard Bio-Tech Co., Ltd., Foshan, 528138, PR China; Key Laboratory of Zoonosis Prevention and Control of Guangdong, Guangzhou, 510642, PR China.
authors.forename: Rui-Ai
authors.initials: RA
authors.lastname: Chen
authors.affiliation: Foshan Standard Bio-Tech Co., Ltd., Foshan, 528138, PR China.
authors.forename: Wen-Li
authors.initials: WL
authors.lastname: Wang
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, PR China; Key Laboratory of Zoonosis Prevention and Control of Guangdong, Guangzhou, 510642, PR China.
authors.forename: Rui-Qing
authors.initials: RQ
authors.lastname: Lin
authors.affiliation: Foshan Standard Bio-Tech Co., Ltd., Foshan, 528138, PR China.
authors.forename: Li-Dan
authors.initials: LD
authors.lastname: Liu
authors.affiliation: Foshan Standard Bio-Tech Co., Ltd., Foshan, 528138, PR China.
authors.forename: Gui-Cheng
authors.initials: GC
authors.lastname: Liao
authors.affiliation: Foshan Standard Bio-Tech Co., Ltd., Foshan, 528138, PR China.
authors.forename: Jian-Hong
authors.initials: JH
authors.lastname: Tang
authors.affiliation: Foshan Standard Bio-Tech Co., Ltd., Foshan, 528138, PR China.
authors.forename: Song-Ming
authors.initials: SM
authors.lastname: Wu
authors.affiliation: Foshan Standard Bio-Tech Co., Ltd., Foshan, 528138, PR China.
authors.forename: Zhi-Jian
authors.initials: ZJ
authors.lastname: Tan
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, PR China; Key Laboratory of Zoonosis Prevention and Control of Guangdong, Guangzhou, 510642, PR China. Electronic address: ybweng@qq.com.
authors.forename: Ya-Biao
authors.initials: YB
authors.lastname: Weng
mesh_terms: D000818:Animals; D002432:Cecum / Q000469:parasitology; D002645:Chickens / Q000469:parasitology*; D003048:Coccidiosis / Q000276:immunology / Q000469:parasitology / Q000517:prevention & control / Q000662:veterinary*; D004539:Eimeria / Q000276:immunology / Q000302:isolation & purification*; D005243:Feces / Q000469:parasitology; D007114:Immunization / Q000662:veterinary*; D007117:Immunization, Secondary / Q000662:veterinary; D007422:Intestines / Q000469:parasitology / Q000473:pathology; D033661:Oocysts; D011201:Poultry Diseases / Q000276:immunology / Q000469:parasitology* / Q000517:prevention & control; D011897:Random Allocation
keywords: Artificial second immunization; Chicken; Eimeria necatrix; Excretion pattern; Precocious line