Effect of diclazuril on intestinal morphology and SIgA expression in chicken infected with Eimeria tenella

Anticoccidial potentials of Azadirachta indica ethosomal nanovesicle in broiler chicks

This study evaluated the efficacy of Azadirachta indica ethosomal nanovesicle against Eimeria tenella infection in broiler chicks. Azadirachta indica ethanolic extract was screened phtochemically and analyzed active components of the extracts using high‑performance liquid chromatography (HPLC). Azadirachta indica ethosomal nanovesicle was synthesized and characterized by zeta potential and scanning electron microscope. Broiler chicks were allocated into seven groups. Control group. The second group administered nanosized ethosomal vesicles (1 mL/kg b.wt.). The third group administered Azadirachta indica nanovesicles (30 mg/kg b.wt.) from 10th day of age. Fourth group was infected with E. tenella at a dose of 1 mL containing 40000 oocyst/ chick at 14th day of age. The fifth group administered Azadirachta indica nanovesicle (30 mg/kg b.wt.) from 10th day of age and infected with E. tenella as fourth group. The sixth group infected with E. tenella as the fourth group and treated with Azadirachta indica nanovesicle (30 mg/kg b.wt. for 4 days after clinical signs appearance. The seventh group infected with E. tenella as the fourth group and treated with diclazuril group (1 mL/4 L of water) for 2 successive days. Coccidiosis significantly decreased body weight, feed intake, reduced glutathione (GSH) level while increased feed conversion ratio, oocyst count, malonaldehyde (MDA) and nitric oxide (NO) serum levels, protein expression of interleukin-1 beta (IL-1β), interleukin 6 (IL-6), BAX and Caspase 3, in cecal tissue and induced cecal tissue injury. However, administration of coccidiosis chicks Azadirachta indica nanovesicle enhanced body weight, and serum GSH. While decreased feed intake, feed conversion ratio, oocyst count, MDA, and NO serum levels, and protein expression of IL-1β, IL-6, BAX, and caspase 3 in cecal tissues and ameliorated cecal tissue damage. This study indicated that, A. indica ethosomal nanovesicle had potent anticoccidial properties.

Effects of prebiotic (lactoferrin) and diclazuril on broiler chickens experimentally infected with Eimeria tenella

Introduction

Avian coccidiosis presents a significant challenge to the poultry industry in Egypt, highlighting the urgent need for validating new drug targets offering promising prospects for the development of advanced anticoccidials. Although numerous reports highlight the activity of lactoferrin (LF) against various microorganisms, its potential against Eimeria has not been explored. The present study evaluated the potential anticoccidial effect of LF and diclazuril in broiler chickens experimentally infected with Eimeria tenella.

Methods

A total of 100 one-day-old broiler chicks were divided into five equal groups (20 each) as follows: Group 1 (G1) served as the normal healthy control group, Group 2 (G2) consisted of chickens infected with 1 × 105 sporulated E. tenella oocysts at 14 days of age, Group 3 (G3) comprised infected chickens treated with diclazuril (0.5 mL/L in drinking water) for 3 days successively, Group 4 (G4) included infected chickens treated with LF (at a dose of 250 mg/kg of diet) from one day of age until the end of the study, and Group 5 (G5) comprised infected chickens treated with both LF and diclazuril.

Results

The positive control group (G2) experienced significant reductions in body weight (BW), BW gain, serum glucose, lipase, amylase, total antioxidant capacity, several hematological indices, and total proteins, along with alterations in various antioxidant enzymes. Conversely, serum levels of aspartate aminotransferase (AST), Alanine aminotransferase (ALT), Alkaline phosphatases (ALP), urea, creatinine, nitric oxide, mean corpuscular volume (MCV), White blood cells (WBCs), heterophils, alpha 2, beta 1, and liver contents of malondialdehyde were elevated in this group. Moreover, higher oocyst counts and lesion scores, along with histopathological alterations, were observed in G2. Remarkably, treatment with diclazuril and/or LF demonstrated potent antioxidant and anticoccidial effects, resulting in reduced shedding of oocysts, lesion scores, and lymphocytic infiltrates in the cecum. Additionally, these treatments improved the antioxidant and immune systems in chickens and restored all histopathological changes reported in the infected non-treated group (G2).

Conclusion

This study offers novel perspectives on the potential anticoccidial effects of the combination of LF and diclazuril in broiler chickens infected with E. tenella, highlighting the potential synergistic actions of LF in treating poultry coccidiosis.

Anticoccidial activity of Aloe Vera Leafs' aqueous extract and vaccination against Eimeria tenella: pathological study in broilers

This study aimed to assess the efficacy of an anticoccidial vaccine and the anticoccidial activity of Aloe vera in broiler chickens infected with Eimeria tenella (E. tenella). A total of 225 healthy, sexless, one-day-old broiler chicks (avian48) from a commercial broiler company were randomized into nine experimental groups of 25 chicks. The groups were as follows: Group 1 (control, vaccinated, non-infected), Group 2 (vaccinated and infected with 5 × 104 sporulated oocysts), Group 3 (vaccinated, infected with 5 × 104 sporulated oocysts, and treated with Aloe vera), Group 4 (infected with 5 × 104 sporulated oocysts and treated with Aloe vera), Group 5 (positive control, infected with 5 × 104 sporulated oocysts), Group 6 (challenged with 5 × 104 sporulated oocysts and then treated with amprolium), Group 7 (treated with amprolium), Group 8 (blank control negative group), and Group 9 (treated with Aloe vera gel).Various parameters were evaluated, including clinical signs, growth performance, oocyst shedding, hematological and immunological parameters, and pathological lesion scoring. The results demonstrated that Aloe vera improved growth performance, reduced oocyst shedding, and decreased caecal lesion scores in E. Tenella-infected broiler chicks. The use of Aloe vera in combination with either amprolium or anticoccidial vaccines provided a potential solution to the issues of drug resistance and drug residues.In conclusion, this study provides valuable insights regarding the control of coccidiosis in broilers. Supplementing the chicken diet with Aloe vera had beneficial effects on the pathogenicity and infectivity of E. tenella, making it a cost-effective alternative as an herbal extract with no adverse side effects for coccidiosis control. These findings suggest that Aloe vera can be considered a potential candidate for inclusion in broiler diets for effective coccidiosis control.

Therapeutic effect of a self-made herbal formula on a multi-drug resistant Eimeria tenella isolate infection in broiler chickens

In-feed prophylactic chemotherapy is widely considered the mainstay of avian coccidiosis control, while serious drug resistance strictly restricts its application. Confronted with the urgent need for an alternative strategy, a traditional Chinese medicine formula (TCMF) was developed. Meanwhile, its potential to iron out complicated clinical coccidiosis was scrutinized in vivo with a field-isolated multi-drug resistant Eimeria tenella (E. tenella) isolate. Birds were inoculated with 5 × 104 sporulated oocysts and administrated with TCMF supplementation in water from 72 h post-infection to the end of the experiment, diclazuril (DIC) was set as a positive control. As a result, TCMF intervention reduced oocyst shedding, cecal lesion and mortality, and enhanced body weight gain. According to the above, anticoccidial index (ACI) was calculated and TCMF exerted a moderate anticoccidial activity. Besides, macroscopic, histopathological, and ultrastructural observations revealed the safeguarding effects of TCMF on E. tenella-induced cecal injury. Following, TCMF treatment presented an obvious inhibition effect on E. tenella caused oxidative stress and inflammatory response. Moreover, TCMF supplementation restored the cecal flora abundance and diversity, reduced the colonization of harmful bacteria, and increased the probiotics abundance. In conclusion, TCMF exhibited a moderate anticoccidial effect along with alleviating E. tenella-induced cecal injury, redox imbalance, and inflammatory response which may be associated with the microflora modulatory effect.

Diclazuril-induced expression of CDK-related kinase 2 in the second-generation merozoites of Eimeria tenella

Diclazuril is a classic anticoccidial drug. The key molecules of diclazuril in anticoccidial action allows target screening for the development of anticoccidial drugs. Cyclin-dependent kinases (CDK) are prominent target proteins in apicomplexan parasites. In this study, a diclazuril anticoccidiosis animal model was established, and the transcription and translation levels of the CDK-related kinase 2 of Eimeria tenella (EtCRK2) were detected. mRNA and protein expression levels of EtCRK2 decreased in the infected/diclazuril group compared with those in the infected/control group. In addition, immunofluorescence analysis showed that EtCRK2 was localised in the cytoplasm of the merozoites. The fluorescence intensity of EtCRK2 in the infected/diclazuril group was significantly weaker than that in the infected/control group. The anticoccidial drug diclazuril against E.tenella affects the expression pattern of EtCRK2 molecule, and EtCRK2 is a potential target for new drug development.

Anticoccidial Activity of Aloe Vera Leafs’ Aqueous Extract and vaccination Against Eimeria tenella: Pathological Study in Broilers.. [DOI: 10.21203/rs.3.rs-3158113/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

This study aimed to assess the efficacy of an anticoccidial vaccine and the anticoccidial activity of Aloe vera in broiler chickens infected with Eimeria tenella. A total of 225 healthy one-day-old, unsexed broiler chicks (avian48) from a commercial broiler company were randomly divided into nine experimental groups, with 25 chicks in each group. The groups included: Group 1 (control, vaccinated, non-infected), Group 2 (vaccinated and infected with 5×104 sporulated oocysts), Group 3 (vaccinated, infected with 5×104 sporulated oocysts, and treated with Aloe vera), Group 4 (infected with 5×104 sporulated oocysts and treated with Aloe vera), Group 5 (positive control, infected with 5×104 sporulated oocysts), Group 6 (challenged with 5×104 sporulated oocysts and then treated with amprolium), Group 7 (treated with amprolium), Group 8 (blank control negative group), and Group 9 (treated with Aloe vera gel). Various parameters including clinical signs, growth performance, oocyst shedding, hematological and immunological parameters, and pathological lesion scoring were evaluated. The results showed that Aloe vera improved growth performance, reduced oocyst shedding, and decreased caecal lesion scores in broiler chicks infected with Eimeria tenella. The use of Aloe vera in combination with either amprolium or anticoccidial vaccines provided a potential solution to the issues of drug resistance and drug residues. In conclusion, this study provides valuable insights into the control of coccidiosis in broilers. Supplementing the chicken diet with Aloe vera had beneficial effects on the pathogenicity and infectivity of Eimeria tenella, making it a cost-effective alternative as an herbal extract with no adverse side effects for coccidiosis control. These findings suggest that Aloe vera can be considered as a potential candidate for inclusion in broiler diets to effectively control coccidiosis.

Comparison of the caecal microbial community structure and physiological indicators of healthy and infection Eimeria tenella chickens during peak of oocyst shedding

Eimeria tenella (E. tenella), an important intestinal parasite of chicken caeca, causes coccidiosis and brings large economic losses to the poultry industry annually. Gut microorganismal alterations directly affect the health of the body. To understand how E. tenella affects its host, we analysed the changes in caecal microbial diversity and the physiological and morphological changes during the peak of oocyst shedding. Infected and healthy chickens differed significantly in caecal pathology and blood indicators. At the genus level, the abundances of Faecalibacterium, Clostridium, Lachnoclostridium, Gemmiger, Flavonifractor, Pseudoflavonifractor and Oscillibacter were significantly decreased in the infected samples, whereas Escherichia, Nocardia and Chlamydia were significantly increased. Functional gene pathways related to replication, recombination and repair, and transcription were significantly decreased, and functional genes related to metabolism were highly significantly reduced in the infected samples. Furthermore, in the infected samples, E. tenella reduced the haemoglobin levels and red blood cell counts, greatly reduced the beneficial bacteria and increased the potentially pathogenic bacteria. This study provides a research basis for further understanding the pathogenic mechanisms of E. tenella and provides insight for potential new drug development.RESEARCH HIGHLIGHTS First simultaneous description of caecal microbiota and physiological indicators during E. tenella infection.Metagenomics used to explore functional properties of chicken caecal microbiota during E. tenella infection.Caecal microbial compositions and functional genes altered significantly after infection.Blood indicators and caecal morphology were significantly altered in the infected group.

Recombinant GMA56 and ROP17 of Eimeria magna conferred protection against infection by homologous species

One of the most common rabbits coccidia species, Eimeria magna is mainly parasitic in the ileal and jejunal epithelial cells. E. magna infection can affect the growth performance of rabbits or cause other secondary diseases. Traditional methods of anticoccidial treatment typically result in drug resistance and drug residue. Therefore, vaccination is a promising alternative. Gametocyte antigen 56 (GAM56) and rhoptry kinase family proteins (ROPs) are involved in oocyst wall formation and parasite invasion, respectively. A virulence factor, ROP17 contains a serine/threonine kinase catalytic domain. In this study, recombinant E. magna GAM56 (rEmGAM56) and ROP17 (rEmROP17) proteins were obtained from a prokaryotic expression system and their reactogenicity was investigated with immunoblotting. To assess the potential of rEmGAM56 and rEmROP17 as coccidiosis vaccines, New Zealand White rabbits were subcutaneously immunized with 100 μg rEmGAM56 (rGC group) or rEmROP17 (rRC group) twice at 2-week intervals followed by homologous oocyst challenge. The rabbit serum was collected weekly to detect the specific antibody levels. The cytokine levels of pre-challenge serum were measured by enzyme-linked immunosorbent assay and the rabbits were observed and recorded post-challenge for the onset of clinical symptoms. The weight gain, oocyst output, and feed conversion ratio were calculated at the end of the experiment. The results showed that both rEmGAM56 and rEmROP17 had good reactogenicity. The rEmGAM56- or rEmROP17-immunized rabbits had milder clinical symptoms and feed conversion ratios of 3.27:1 and 3.37:1, respectively. The rEmGAM56-immunized rabbits had 81.35% body weight gain and 63.85% oocyst output reduction; the rEmROP17-immunized rabbits had 79.03% body weight gain and 80.10% oocyst output reduction. The ACI of rGC and rRC groups were 162.35 and 171.03, respectively. The specific antibody levels increased rapidly after immunization. Significantly increased interleukin (IL)-2, interferon (IFN)-γ, and IL-17 levels were evident in the rGC and rRC groups (p < 0.05). The rEmGAM56 and rEmROP17 elicited humoral and cellular responses, which protected against E. magna infection in rabbits. Thus, rEmGAM56 and rEmROP17 are potential vaccine candidates against E. magna, and rEmROP17 performed better than rEmGAM56.

Interactions of Microbiota and Mucosal Immunity in the Ceca of Broiler Chickens Infected with Eimeria tenella

The purpose of the study was to investigate the effects of Eimeria tenella infection on the cecal microbiome, the protein concentration of cecal content, cecal mucosal immunity, and serum endotoxin levels in broilers. Three hundred sixty 14-day-old broilers were allocated to five infection doses with six replicates. The five infection doses were: ID0: 0, ID1: 6250, ID2: 12,500, ID3: 25,000, and ID4: 50,000 Eimeria tenella oocysts. Eimeria tenella infection significantly increased the relative abundance of the phylum Proteobacteria, which includes diverse pathogenic bacteria, and significantly decreased the relative abundance of the phylum Firmicutes. Protein concentration of the cecal content was linearly increased (p < 0.05), and the concentration of secretory immunoglobulin A (sIgA) in the cecal content was linearly decreased by Eimeria tenella infection (p < 0.05). Goblet cell density was linearly reduced in the ceca by Eimeria tenella infection (p < 0.05). Eimeria tenella infection tended to linearly decrease the relative mRNA expression of antimicrobial peptide genes such as avian beta-defensin 9 (AvBD9; p = 0.10) and liver-expressed antimicrobial peptide 2 (LEAP2; p = 0.08) in the cecal tissue. Therefore, Eimeria tenella infection negatively modulated cecal microbiota via impairing cecal mucosal immunity and increasing protein concentration in the cecal content in broilers.

Research Note: Transcriptomic analysis of LMH cells in response to the overexpression of a hypothetical protein identified in Eimeria tenella SD-01 strain

Though genome sequencing of Eimeria tenella predicts more than 8,000 genes, the molecular functions of many proteins remain unknown. In this study, the coding region corresponding to the mature peptide of a hypothetical protein of E. tenella (ETH_00023950) was amplified and expressed in a bacterial system. Following preparation of polyclonal antibody that recognizes ETH_00023950, the expression of ETH_00023950 in merozoites was examined. Meanwhile, we determined the transcriptomic responses of the leghorn male hepatoma (LMH) cells to its expression. Sequencing analysis showed that one single nucleotide polymorphism and one indel of ETH_00023950 of E. tenella SD-01 strain were found compared with that of the UK reference Houghton strain, leading to a frame shift and a premature stop codon. The expression of ETH_00023950 in E. tenella merozoites was confirmed by indirect immunofluorescence and Western blot analysis. Transcriptomic analysis showed that ETH_00023950 altered the expression of 2,680 genes (321 downregulated genes and 2,359 upregulated genes) in LMH cells. The RNA-sequencing data were consistent with the results of the quantitative real-time polymerase chain reaction (qRT-PCR). Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that differentially expressed transcripts were significantly related to 8 pathways, including oxidative phosphorylation and TGF-beta signaling pathway. These findings contribute to understanding host-pathogen interaction and secondary bacterial infections related to E. tenella.

Identification and Protective Efficacy of Eimeria tenella Rhoptry Kinase Family Protein 17

Simple Summary

Approximately 8000 genes of Eimeria tenella have been found by genome sequencing, whereas very few data are currently available regarding E. tenella rhoptry kinase family proteins. In this study, the coding sequence of the rhoptry kinase family protein 17 of E. tenella (EtROP17) was cloned and expressed in Escherichia coli, and then the protective efficacy of the recombinant EtROP17 (rEtROP17) was assessed in chickens. Sequence analysis showed that a single base difference at position 1901 of the ROP17 of the SD-01 strain was observed compared with that of the Houghton strain. EtROP17 was expressed in the merozoite stage of E. tenella and may be a potential vaccine candidate against coccidiosis.

Abstract

Eimeria tenella encodes a genome of approximately 8000 genes. To date, however, very few data are available regarding E. tenella rhoptry kinase family proteins. In the present study, the gene fragment encoding the mature peptide of the rhoptry kinase family protein 17 of E. tenella (EtROP17) was amplified by PCR and expressed in E. coli. Then, we generated polyclonal antibodies that recognize EtROP17 and investigated the expression of EtROP17 in the merozoite stage of E. tenella by immunofluorescent staining and Western blot analysis. Meanwhile, the protective efficacy of rEtROP17 against E. tenella was evaluated in chickens. Sequencing analysis showed that a single base difference at sequence position 1901 was observed between the SD-01 strain and the Houghton strain. EtROP17 was expressed in the merozoite stage of E. tenella. The results of the animal challenge experiments demonstrated that vaccination with rEtROP17 significantly reduced cecal lesions and oocyst outputs compared with the challenged control group. Our findings indicate that EtROP17 could serve as a potential candidate for developing a new vaccine against E. tenella.

Anticoccidial effect of Fructus Meliae toosendan extract against Eimeria tenella

CONTEXT

Fructus Meliae toosendan extracts (FMTE) have a good therapeutic effect on coccidiosis, but there is no relevant research on its prophylactic effect on coccidiosis.

OBJECTIVE

This study comprehensively evaluates the anticoccidial effect of FMTE.

MATERIALS AND METHODS

In vitro, the unsporulated oocysts were treated with serial dilutions of FMTE and incubated for 7 d, and the sporulated oocysts were counted for calculating the median lethal concentration (LC₅₀) of FMTE. In vivo, 180 10-day-old broiler chickens free of coccidiosis were weighted and randomly distributed into six groups: normal group, untreated group, 4 protective groups (positive group and three FMTE groups). From day 10 to day 21, chickens in the three FMTE groups were pre-treated with FMTE at the dosage of 2.5, 5 and 10 g/kg/d, respectively, and chickens in the positive group were pre-treated with qiuliling (10 g/kg/d). On day 14, chickens in all groups except the normal group were orally infected with 1.5 × 10⁴ sporulated oocysts. The clinical symptoms were observed from day 10 to day 21, the anticoccidial index (ACI), tissue lesions, and intestinal microflora were determined on day 21.

RESULTS

FMTE showed anti-sporulation effect against E. tenella and the LC₅₀ value was 245.83 µg/mL in vitro. In vivo, FMTE at the dosage of 10 g/kg/d was effective against E. tenella infection, and its ACI value was 162.56, which was higher than the value of positive drug qiuliling (128.81). Discussion and conclusions: FMTE have potent anticoccidial effects, and it presents an alternative anticoccidial agent for avian coccidiosis control.

Effects of diclazuril on the expression of enolase in second-generation merozoites of Eimeria tenella

Eimeria tenella is an obligate intracellular parasite of the chicken cecum; it brings huge economic loss to the chicken industry. Enolase is a multifunctional glycolytic enzyme involved in many processes of parasites, such as infection and migration. In this study, the effect of diclazuril on the expression of enolase in second-generation merozoites of E. tenella (EtENO) was reported. The prokaryotic expression plasmid pET-28a-EtENO was constructed and transformed into Escherichia coli BL21 (DE3). Then, it was subjected to expression under the induction of isopropyl-β-D-1-thiogalactopyranoside. The expressed products were identified and purified. The purified EtENO protein was used for antibody preparation. The EtENO mRNA and protein expression levels were analyzed via real-time PCR and Western blotting. Localization of EtENO on the merozoites was examined by immunofluorescence technique. The mRNA and protein expression levels of EtENO were decreased by 36.3 and 40.36%, respectively, by diclazuril treatment. EtENO distributed in the surface, cytoplasm, and nucleus of the infected/control group. With diclazuril treatment, it was significantly reduced in the surface and cytoplasm and even disappeared in the nucleus of the infected/diclazuril group. These observations suggested that EtENO may play an important role in mechanism of diclazuril anticoccidial action and be a potential drug target for the intervention with E. tenella infection.

Influence of Mushroom Polysaccharide, Nano-Copper, Copper Loaded Chitosan, and Lysozyme on Intestinal Barrier and Immunity of LPS-mediated Yellow-Feathered Chickens

This study investigated the influence of dietary supplementation with some antibiotic alternatives on growth performance, intestinal barrier, and immunity of lipopolysaccharide (LPS) challenged chicks. Wenshi females, aged 4 days, were allocated randomly into eight groups, each with six replicates of 20 birds (n = 120/treatment), which received a basal diet supplemented with 0 (control), 0 (LPS), 200 mg/kg aureomycin, 50 mg/kg mushroom polysaccharide, 100 mg/kg mushroom polysaccharide, 500 mg/kg nano-copper, 300 mg/kg copper loaded chitosan, and 500 mg/kg lysozyme for 21 days. On day 18 and 20, the control birds were injected with 0.5 mL saline solution, the other treatments were injected with 0.5 mL saline containing 500 µg LPS/kg body weight (BW). The results indicated that LPS treatment reduced the BW, average daily gain (ADG), and daily feed intake (ADFI) than the controls (p < 0.05), and the antibiotic and the tested alternatives could not retrieve the normal BW, ADG, and ADFI. The tested additives reduced several negative effects of LPS; they reduced diamine oxidase activity and inflammatory mediators in plasma, jejunal mucosa, spleen and thymus, increased content of immunoglobulin in plasma and jejunal mucosa, and decreased gene expression of inducible nitric oxide synthase and Cyclooxygenase 2 in jejunal mucosa.

Effects of Eimeria tenella infection on the barrier damage and microbiota diversity of chicken cecum

The symbiosis of host and intestinal microbiota constitutes a microecosystem and plays an important role in maintaining intestinal homeostasis and regulating the host's immune system. Eimeria tenella, an obligate intracellular apicomplexan parasite, can cause coccidiosis, a serious intestinal disease. In this study, the effects of E. tenella infection on development parameters (villus height, crypt depth, mucosa thickness, muscularis thickness, and serosa thickness) and microbiota in chicken cecum were investigated. Fourteen-day-old male Hy-Line Variety Brown layer chickens were inoculated with sporulated oocysts of E. tenella. Cecal tissues were collected 7 d after inoculation. Relative density of goblet cells and glycoproteins were determined by Alcian blue periodic acid–Schiff staining and periodic acid–Schiff staining, respectively. Intestinal development parameters were also evaluated. Cecal contents were extracted, and the composition of cecal microflora was examined by Illumine sequencing in the V3–V4 region of the 16S rRNA gene. Results indicated that E. tenella infection destroyed the structure of cecal tissue and reduced the relative density of goblet cells and glycoproteins. Sequencing analysis indicated that E. tenella infection altered the diversity and composition of cecal microbiota. The populations of Proteobacteria, Enterococcus, Incertae, and Escherichia–Shigella decreased, and those of Bacteroidales and Rikenella significantly increased in the infected group compared with those in the control group. Hence, the pathological damage caused by E. tenella infection is associated with cecal microbiota dysbiosis, and this finding may be used to develop an alternative measure for alleviating the effect of coccidiosis on the poultry industry.

Dual-sensitive chitosan derivative micelles for site-specific drug release in the treatment of chicken coccidiosis

Here, we report a “dual-sensitive” drug delivery platform packaged with anti-coccidia drug diclazuril (DIC) applied in the field of intestinal-targeted administration.

Effect of Diclazuril on the Bursa of Fabricius Morphology and SIgA Expression in Chickens Infected with Eimeria tenella

The effects of diclazuril on the bursa of Fabricius (BF) structure and secretory IgA (SIgA) expression in chickens infected with Eimeria tenella were examined. The morphology of the BF was observed by hematoxylin and eosin staining, while ultrastructural changes were monitored by transmission electron microscopy. E. tenella infection caused the BF cell volumes to decrease, irregularly arranged, as well as, enlargement of the intercellular space. Diclazuril treatment alleviated the physical signs of damages associated with E. tenella infection. The SIgA expression in BF was analyzed by immunohistochemistry technique. The SIgA expression increased significantly by 350.4% (P<0.01) after E. tenella infection compared to the normal control group. With the treatment of diclazuril, the SIgA was relatively fewer in the cortex, and the expression level was significantly decreased by 46.7% (P<0.01) compared with the infected and untreated group. In conclusion, E. tenella infection in chickens induced obvious harmful changes in BF morphological structure and stimulated the expression of SIgA in the BF. Diclazuril treatment effectively alleviated the morphological changes. This result demonstrates a method to develop an immunological strategy in coccidiosis control.