Search Results (47)

Non-drug additives are being evaluated for mitigating necrotic enteritis in broilers. This study examined the effects of phytogenic blends on performance, pathology, and mRNA abundance of tight junction and immune response genes during NE challenge. One-day (d)-old male broilers (n = 600) were allocated into four treatments (six pens/treatment, 25 birds/pen): NC (basal), PC (NC + 15 ppm avilamycin and 125 ppm amprolium), PHY1 (NC + Alterna^®), and PHY2 (NC + Alterna + Synbiotec^®). All birds were challenged with Eimeria maxima (d 14) and Clostridium perfringens (d 19). Performance was recorded on d 14, 21, 28, and 42, and jejunal samples were collected on d 14, 21, and 42 to assess mRNA abundance. Data were analyzed using ANOVA followed by Fisher’s LSD test (p ≤ 0.05). PC and PHY2 improved daily gain, feed intake, feed conversion ratio, and reduced mortality compared to NC during d 21–28, 0–28, and 0–42. PC, PHY1, and PHY2 had reduced lesion severity than NC (d 21). Greater mRNA abundance of tight junction and immune response genes was observed in PHY2 on d 14, PC on d 21, and PHY1 and PHY2 on d 42. Therefore, supplementation of Alterna and Synbiotec improved performance, reduced pathology, and supported host response during NE challenge. Full article

The moderate pathogenicity coupled with high host susceptibility of Eimeria maxima has precipitated substantial economic losses in the poultry industry. Addressing challenges such as emerging drug resistance underscores the imperative for innovative vaccine strategies. This study developed a novel DNA vaccine to solve this challenge by fusing E. maxima elongation factor-1α (EmEF1α) with chicken chemokine XCL1 (ChXCL1) in the pVAX1 vector. The recombinant plasmid, designated pVAX1-ChXCL1-EmEF1α, was successfully constructed and confirmed to express the ChXCL1-EmEF1α fusion protein in vitro. Immunization of chickens with this DNA vaccine elicited a robust and balanced immune response, characterized by significantly increased proportions of CD4⁺ (11.76%) and CD8⁺ (5.58%) T lymphocytes, elevated levels of Th1-associated cytokines (IFN-γ and IL-12), and strong antigen-specific IgG and IgA antibody responses. Following experimental challenge with E. maxima, vaccinated birds exhibited substantial protection: a 66.4% reduction in oocyst shedding, a 71.7% improvement in relative weight gain, marked attenuation of intestinal lesions, and an anticoccidial index (ACI) of 170. These findings demonstrate that the ChXCL1-EmEF1α DNA vaccine effectively enhances both cellular and humoral immunity. Collectively, this study validates ChXCL1 as a potent molecular adjuvant and establishes the “antigen–adjuvant” fusion DNA platform as a promising strategy for developing next-generation vaccines against avian coccidiosis. Full article

Chicken coccidiosis is a parasitic disease caused mainly by Eimeria tenella, Eimeria acervulina, Eimeria maxima, and Eimeria necatrix, with most cases presenting as mixed infections. Currently, although a subunit vaccine (CoxAbic) targeting Eimeria maxima via maternal immunization is commercially available, no genetically engineered multivalent subunit vaccine exists against mixed infections caused by these four Eimeria species simultaneously. Therefore, we developed a tetravalent recombinant subunit vaccine (designated TEIN) by fusing key antigen genes (TA4, 3-1E, IMP1, NA4) from these four Eimeria species and expressing the construct in Pichia pastoris. A total of 500 chickens were randomly allocated into 25 experimental subgroups (n = 20 each), consisting of five groups (control, challenged, adjuvant, pPIC9K, and TEIN) and five challenge conditions (infection with Eimeria tenella, Eimeria acervulina, Eimeria maxima, Eimeria necatrix, or a mixture of four species). Immunization was performed via leg intramuscular injection at 14 and 21 days of age. At 28 days of age, all chickens except the controls were orally challenged with 1 × 10⁴ sporulated oocysts. Statistical analysis was performed using one-way or two-way ANOVA as appropriate. Results showed that chickens vaccinated with the TEIN subunit vaccine exhibited significantly elevated serum levels of IgY, IL-2, IL-10, and IFN-γ, as well as an increased splenic lymphocyte CD4⁺/CD8⁺ ratio. The anticoccidial indices (ACI) against Eimeria tenella, Eimeria acervulina, Eimeria maxima, and Eimeria necatrix, and their mixed infection reached 174.82, 174.58, 174.41, 180.61, and 175.95, respectively. Moreover, no significant differences were observed in hematological parameters, serum biochemical markers, or histopathological findings between the vaccinated and control groups. These results demonstrate the vaccine’s potential as a promising candidate for controlling mixed coccidial infections. Full article

This study aimed to evaluate the performance, nutrient digestibility, intestinal health, and duodenum gene expression of broilers challenged with Eimeria spp. supplemented with or without monensin sodium. A total of 144 male chicks were used, distributed in a completely randomized design with three treatments: unchallenged control (UN), challenged control (CC), and CC + 100 mg/kg of monensin sodium (MON). Six replicates of eight birds each were used. At 14 days of age, the challenged groups were inoculated with a mixture of Eimeria oocysts, 12,500 E. maxima, 62,500 E. acervulina, and 12,500 E. tenella oocysts/chick. Coccidial challenge impaired growth performance and nutrient digestibility and induced intestinal damage, as evidenced by reduced body weight gain and feed intake (p < 0.001), lower apparent digestibility coefficients (p < 0.001), and altered intestinal morphometry and ISI score in the jejunum and cecum (p < 0.001). Monensin supplementation partially alleviated these negative effects, improving performance and nutrient digestibility (p < 0.001) and delaying oocyst excretion (p = 0.006) when compared with the CC group. However, the duodenal expression of tight junction-related genes, as well as intestinal integrity and health parameters, remained impaired despite monensin supplementation. It is concluded that monensin preserves nutrient digestibility and attenuates performance loss in broilers challenged with Eimeria spp. but not reduced intestinal damage. Full article

Avian coccidiosis is an intestinal disease caused by Eimeria spp. infection. A deeper understanding of the interaction between host gut microbiota and the Eimeria parasite is crucial for developing alternative therapies to control avian coccidiosis. Here, we used full-length sequencing of 16S ribosomal RNA amplicons to compare changes in the gut microbiota of chickens infected with Eimeria tenella, Eimeria maxima, and Eimeria necatrix, aiming to identify both species-specific and common alterations in gut microbiota at 4 and 10 days post-infection. The result revealed that infection with all three Eimeria species led to a decrease in the abundance of the microbial genera Limosilactobacillus, Streptococcus, Alistipes, Lactobacillus and Phocaeicola, while the abundance of Bacteroides, Escherichia and Ligilactobacillus increased. Escherichia and Enterococcus were most abundant in the jejunum of the E. necatrix-infected group and in the cecum of the E. tenella-infected group, whereas Megamonas abundance was highest in the E. maxima-infected group. LEfSe analysis showed that infection with all three Eimeria species significantly reduced the abundance of 13 bacterial species, including Acetilactobacillus jinshanensis, Bacteroides ndongoniae, Barnesiella viscericola, Christensenella minuta, Enterocloster clostridioformis, Gemella haemolysans_A, Granulicatella adiacens, Lawsonibacter sp000177015, Limosilactobacillus reuteri, Limosilactobacillus reuteri_D, Limosilactobacillus vaginalis_A, Limosilactobacillus caviae, Limosilactobacillus vaginalis. Infection with E. tenella significantly increased the abundance of five bacterial species, including Bacteroides fragilis, Enterococcus cecorum, Helicobacter pylori, Methylovirgula ligni, and Phocaeicola sp900066445. Infection with E. maxima significantly increased the abundance of seven bacterial species, including Clostridioides difficile, Faecalibacterium prausnitzii, Mediterraneibacter torques, Muribaculum intestinale, Mediterraneibacter massiliensis, Phascolarctobacterium faecium, and Phocaeicola plebeius. Infection with E. necatrix significantly increased the abundance of seven bacterial species, including Alistipes sp900290115, Anaerotignum faecicola, Bacteroides fragilis_A, Escherichia coli, Harryflintia acetispora, Pseudoclostridium thermosuccinogenes, and Tidjanibacter inops_A. The results showed that Eimeria infection causes significant species- and time-dependent changes in the gut microbiota of chickens. These findings enhance our understanding of coccidiosis pathogenesis and offer potential targets for developing probiotics. Full article

Coccidiosis, caused by Eimeria spp., is a major economic burden in poultry production, prompting growing interest in natural alternatives to synthetic anticoccidials. This study evaluated the use of Polygain™, a sugarcane-derived polyphenol-rich feed material, as a natural anticoccidial in broiler chickens experimentally challenged with Eimeria tenella, E. maxima, and E. acervulina. A total of 144 Ross 308 chicks were allocated to six groups: uninfected–untreated control, infected–untreated control, infected plus nicarbazin + narasin, and three Polygain™ treatment groups (250, 500, and 1000 ppm). Birds were orally challenged with mixed oocysts on day 14. Parameters assessed included body weight gain (BWG), lesion scores (LS), oocyst per gram (OPG), and calculated indices such as relative oocyst production (ROP), reduction in lesion score (RLS), percent optimum anticoccidial activity (POAA), and anticoccidial index (ACI). Polygain™ reduced intestinal lesions (p < 0.05), particularly in the caecum, with complete lesion resolution observed at 1000 ppm by 21 days post-infection. Polygain™ ACI values (143–146) were limited in comparison to nicarbazin + narasin treatment (ACI 160). These findings demonstrate that Polygain™ supplementation confers measurable protective dose related effects against coccidiosis without impairing growth performance, supporting its potential as a natural feed material for integrated coccidiosis management. Full article

Chicken coccidiosis is a major parasitic disease in poultry that causes substantial economic losses worldwide. The accurate and simultaneous diagnosis of mixed infections with multiple Eimeria species remains challenging using conventional methods. In this study, we developed a multiplex TaqMan-MGB qPCR assay targeting the ITS1 region for simultaneous detection and quantification of four major pathogenic species: E. acervulina, E. necatrix, E. maxima, and E. tenella. The assay exhibited high specificity without cross-reactivity and achieved a sensitivity 100-fold greater than conventional PCR, with detection limits ranging from 10¹ to 10² copies/μL. Standard curves demonstrated strong linearity (R² ≥ 0.95) and amplification efficiency (95–113%). Repeatability was robust, with intra- and inter-assay CVs below 2%. Applied to 165 clinical samples collected from poultry farms in Fujian Province, China (2022–2024), the assay detected an overall Eimeria infection rate of 93.3%, higher than conventional PCR (89.7%). Epidemiological analysis revealed E. tenella (78.8%, [130/165]) and E. necatrix (78.8%, [130/165]) were dominant, while mixed infections were frequent (83.3%, [136/154]), including dual (45.5%, [70/154]), triple (31.2%, [48/154]), and quadruple (11.7%, [18/154]) infections. This multiplex TaqMan-MGB qPCR provides a rapid, sensitive, and quantitative tool for detecting multiple Eimeria species, greatly improving diagnostic efficiency and supporting clinical diagnosis, surveillance, and control strategies. Full article

Coccidiosis is a major parasitic disease that suppresses poultry productivity and causes significant global economic losses. Currently, controlling Eimeria parasites relies primarily on the use of anticoccidial drugs or live vaccines. However, these conventional control strategies face the dual constraints of escalating drug resistance and unsustainable economic expenditures. In this study, the efficacy of a chimeric subunit vaccine comprising Eimeria maxima Elongation Factor-1α (EmEF1α) and chicken chemokine Ligand-1 (ChXCL1) was assessed for protection against experimental Eimeria maxima infection. The synthetic gene fragment ChXCL1-EmEF1α was ligated to the pET28a vector and expressed in vitro. Western blot analysis confirmed the successful expression of the recombinant ChXCL1-EmEF1α protein. Chickens immunized with the ChXCL1-EmEF1α exhibited a significantly stronger IgY response and higher secretion of IL-2 and IL-17 compared to those vaccinated with recombinant ChXCL1 alone or challenged solely with E. maxima. Furthermore, the ChXCL1-EmEF1α group demonstrated enhanced anticoccidial effects, including reduced intestinal lesions, higher body weight gain, and lower oocyst shedding compared to control groups. Following E. maxima challenge, the EmEF1α and ChXCL1-EmEF1α groups demonstrated robust protective efficacy, achieving high ACI values of 182 and 178, respectively. In contrast, the ChXCL1 and UC groups exhibited significantly lower ACI values (150 and 149, respectively), indicating minimal protection. This improvement was also reflected in the immune response, with significantly elevated levels of CD4⁺ and CD8⁺ T cells in the ChXCL1-EmEF1α-treated chickens. Moreover, ChXCL1 acts as an effective adjuvant when fused with EmEF1α, enhancing the vaccine’s anticoccidial efficacy. These results suggest that the ChXCL1-EmEF1α chimeric immunogen is a promising candidate for developing subunit vaccines against E. maxima infections. Full article

Coccidiosis, caused by Eimeria spp., remains a major challenge in poultry production, significantly affecting poultry health and performance, leading to substantial economic losses. While its impact on gut health is well documented, the interplay of Eimeria spp. challenge and/or vaccination with the intestinal microbiota remain insufficiently understood. Therefore, the aim of this study was to investigate the effects of Eimeria spp. (E. acervulina, E. maxima, and E. tenella) challenge, alone or in combination with a commercially available vaccine, on broiler performance, intestinal gross lesions, and cecal microbiota structure and function in experimentally challenged broiler chicks. A total of 216 Ross 308^® broilers were randomly divided into three groups, with six replicates per group, according to the following experimental design: (A) negative control, (B) Eimeria spp.-challenged birds on day 16, and (C) Eimeria spp.-vaccinated and -challenged birds. Performance parameters were recorded on a weekly basis, coccidiosis gross lesions in the intestine were evaluated on days 23 and 29, and microbiota samples were collected on day 23. Broilers in the challenged group exhibited significantly (p ≤ 0.05) increased coccidiosis gross lesions in the intestine at both sampling periods (7 and 19 days post-infection, dpi), whereas vaccination significantly (p ≤ 0.05) minimized the severity of lesions at both time points. The challenged-only group showed significantly (p ≤ 0.05) lower average daily weight gain (ADWG) during the finisher phase and the overall experimental period compared to the vaccinated group. Additionally, average daily feed intake (ADFI) during the post-challenge period (22–29 dpi) was significantly (p ≤ 0.05) reduced in both challenged groups. Alpha diversity decreased in the challenged (p = 0.016) and vaccinated–challenged (p = 0.016) groups compared to control, Accordingly, beta diversity was reduced in groups B and C compared to the control group. This reduction was accompanied by an increased relative abundance of Proteobacteria (18, 71% in Group B and 10, 87% in Group C) and potentially pathogenic genera (Escherichia spp. and Shigella spp. p < 0.05), along with a decline in short-chain fatty acid (SCFA)-producing bacteria (Oscillibacter spp. and Eisenbergiella spp.) in groups B and C, respectively, compared to the control. Predictive functional metagenomics indicated disruptions in amino acid metabolism, nucleotide degradation, and lipid metabolism, potentially affecting gut integrity and nutrient absorption. Additionally, in the vaccinated group, gross lesions in the intestine were reduced in severity and microbial diversity was partially preserved, resulting in a microbiota composition more similar to that of the control group. Overall, these findings support that Eimeria spp. infection alters gut microbiota and function in broiler chicks, underscoring the need for further research into alternative strategies, such as probiotics and phytobiotics, to support gut health and disease resilience in poultry. Full article

Coccidiosis is a major economic threat in poultry, and with anticoccidials being phased out, cost-effective alternatives like copper (Cu) supplementation are of interest. This study investigated whether in-feed monovalent Cu (100 ppm) could mitigate the effects of a mild Eimeria challenge in broilers. A total of 216 broiler chicks were randomly assigned to three treatments (six replicates, 12 birds/replicate): unchallenged control (NC), challenged control (PC), and challenged + Cu-supplemented. Birds were fed starter (days 1–10), grower (days 10–21), and finisher (days 21–35) diets. On day 14, all birds except the NC group were orally challenged with 5000 oocysts each of Eimeria acervulina and E. maxima. Feces were collected (days 17–28) for oocyst count, and growth performance, lesion scores (day 21), carcass traits and bone morphology (day 35), gut morphology (days 21 and 35), gizzard weight (days 21 and 35), and cecal bacterial load (days 21 and 35) were evaluated. The mild challenge was confirmed by the observed differences in lesion scores on day 21 (p < 0.05), fecal oocyst counts from days 17–28 (p < 0.05), and overall mortality (p > 0.05) between challenged and unchallenged groups. Copper supplementation tended to improve FCR during the grower phase (1.403 vs. 1.469; p = 0.057) and significantly reduced oocyst excretion on days 23–25 (p < 0.001) compared to the PC treatment. Although performance benefits were limited, Cu reduced oocyst shedding, indicating potential anticoccidial effects. However, further studies are needed to confirm the consistency of this effect across different doses of Cu in poultry production. Full article

Family poultry production systems (FPPSs) in Chile and Argentina produce high-quality and nutritious food. However, little is known about chicken coccidiosis in these production systems. This work aimed to determine the Eimeria sp. positivity rate, circulating species, general farm management, and knowledge of the disease in FPPSs by gaining access to peri-urban markets in these two countries. The overall Eimeria sp. positivity rate, determined in 88 fecal samples, was 85.1%. Oocysts per gram in Argentinean meat-producing FPPSs were significantly higher than in Argentinean and Chilean egg-producing FPPSs. Multiplex-PCR based on seven Eimeria spp. Sequence-Characterized Amplified Region (SCAR) markers showed a great diversity of circulating species, with E. mitis (70.3%), E. acervulina (62.2%), and E. tenella (59.5%), followed by E. maxima (43.2%), E. praecox (32.4%), E. necatrix (18.9%), and E. brunetti (5.4%). Low awareness among family producers and low implementation of control measures were found. Importantly, pathogenic species were found even in asymptomatic chickens, which represents a potential chicken health threat. Furthermore, the administration of sulfonamides to broilers with clinical signs poses a risk of environmental contamination. This is the first comprehensive cross-sectional study showing that Eimeria sp. is a persistent parasite in peri-urban FPPSs in Argentina and Chile. Full article

Clostridium perfringens is a prevalent gut bacterial pathogen in humans and animals. This study investigated the role of the mechanistic targets of rapamycin (mTOR) and deoxycholic acid (DCA) on C. perfringens intestinal infection. Chickens were sequentially infected with Eimeria maxima and received the mTOR inhibitor rapamycin and DCA. C. perfringens-induced necrotic enteritis (NE) was evaluated using body weight gain (BWG), histopathology, bile acids, pathogen colonization, cell infiltration and death, and gene expression. The significant difference of p < 0.05 was analyzed by one-way ANOVA and multiple comparisons. Notably, rapamycin strongly reduced the subclinical and clinical NE histopathologies. DCA and DCA combined with rapamycin alleviated clinical NE and BWG loss. Rapamycin, DCA, and DCA + rapamycin attenuated bile acid reduction in NE birds, and they also reduced immune cell infiltration into the intestinal lamina propria as well as immune cell migration in vitro. At molecular levels, DCA and DCA + rapamycin reduced proinflammatory IFNγ, MMP9, IL23, and IL17 gene expression. Rapamycin, DCA, and DCA + rapamycin reduced NE-induced intestinal cell apoptosis. Together, these results suggest that mTOR signaling mediates C. perfringens-induced ileitis, and combining mTOR inhibition and DCA improves the intervention efficacy against NE ileitis and BWG loss. Full article

The intestinal microbiota is known to be altered by Eimeria-induced coccidiosis, but it remains unclear whether the microbiota is fully restored after recovery. To address this, 110 newly hatched Cobb male broiler chickens were challenged with 2 × 10⁴ sporulated oocysts of Eimeria maxima (EM) strain M6 or mock-infected with saline on day 10. Body weight and feed intake were recorded. Additionally, 10 mock- and 12 EM-infected birds were randomly selected to assess the small intestinal lesion, fecal oocyst shedding, and ileal and cecal microbiota compositions using 16S rRNA gene sequencing at 3, 5, 7, 14, and 21 days post-infection (dpi). EM infection significantly decreased (p < 0.001) body weight by 5 dpi, persisting through 21 dpi. The infection also reduced (p < 0.05) weight gain, feed intake, and feed efficiency in the first week; however, these parameters became comparable in the second and third weeks. At 7 dpi, during the peak of infection, major lactic acid bacteria were enriched, while short-chain fatty acid-producing bacteria were mostly suppressed in both the ileum and cecum. Opportunistic pathogens such as Escherichia and Clostridium perfringens transiently bloomed at 7 dpi. By 14 dpi, differential bacterial enrichment subsided, and nearly all commensal bacteria returned to healthy levels by 21 dpi. Coupled with comparable growth performance between healthy and EM-recovered chickens, we conclude that the intestinal microbiota is largely restored to its healthy state after recovery. Understanding the microbiota’s responses to coccidiosis may inform probiotic-based mitigation strategies. Full article

This study evaluated the effectiveness of phytobiotic supplementation in managing coccidiosis in broiler chickens, a disease that impacts productivity. Three hundred sixty Ross-308 one-day-old chicks were assigned to five treatment groups: control negative (CN), phyto negative (PN), control infected (CI), phyto infected (PI), and salinomycin infected (SI). All diets were fed for the entire experiment duration. CN and CI groups were given a common diet, with CN remaining uninfected and CI exposed to Eimeria spp., while PN and PI groups received a phytobiotic supplement containing essential oils, saponins, and tannins (with PI challenged by Eimeria spp.), and SI received salinomycin post-infection. All infected groups were challenged on day 14 with Eimeria acervulina, E. maxima, and E. tenella. By day 21, PN had the highest body weight (744.9 g). Body weight gain (BWG) was highest in CN and PN from days 14–35, while CI consistently showed the lowest BWG. PI demonstrated significantly lower oocyst counts than CI, outperforming even SI by day 7, and showed milder intestinal lesions. A high anticoccidial index (ACI) of 188.45 was observed in PI, close to uninfected groups, while SI achieved a partially effective ACI of 136.91. Overall, PN and PI exhibited improved performance and intestinal health, highlighting the potential of phytobiotics in coccidiosis management for broilers. Full article

Necrotic enteritis (NE), caused by Clostridium perfringens, represents a major economic challenge to poultry production. This study evaluated the effects of four plant extracts—Astragalus, pomegranate peel, Sophora flavescens, and Artemisia annua—in combination with B. subtilis, as potential antibiotic alternatives for controlling NE. Using an experimentally induced NE model produced by coinfection with Eimeria maxima and C. perfringens, 288 chickens were divided into 12 groups to assess growth performance, intestinal lesions, and inflammatory markers. Compared with the enramycin group, the pomegranate peel extract group had a 9.9% increase in body weight gain (BWG), significant enhancement in claudin-2 expression, and reduced production of inflammatory factors. Compared with the infected control group, the combination of A. annua extract and B. subtilis resulted in the lowest intestinal lesion scores. The claudin-2, occludin, and zonula occludens-1 expression levels in the group treated with S. flavescens extract combined with B. subtilis increased to the highest levels compared to those in the healthy control group. These findings emphasize the potential of plant extracts, particularly pomegranate peel and A. annua with B. subtilis, as natural alternatives for NE management in poultry, providing a promising approach to reducing reliance on antibiotics. Full article