Coccidial Infection Research Articles

Plants, plant‐derived compounds, probiotics, and postbiotics as green agents to fight against poultry coccidiosis: A review

AbstractThe intestinal tract is the main place for animals to digest food and absorb nutrients, which also serves as the first line of defense against pathogens that invade the internal environment. Therefore, normal intestinal structure and function are essential for animal health. Poultry coccidiosis is an intestinal disease primarily caused by the parasitization of intestinal epithelial cells by protozoa of the genus Eimeria. The occurrence of coccidiosis not only compromises the intestinal integrity of poultry but also increases their disease susceptibility, thus posing a serious threat to the overall health and productivity of poultry. Nowadays, the primary methods for controlling and preventing coccidiosis in poultry are anticoccidial drugs or live oocyst vaccines. However, the use of the former may be associated with problems of resistance and drug residues, while the use of the latter may cause intestinal damage and significantly increase farming costs. For these reasons, it is critical to investigate green, safe, and cost‐effective natural alternative strategies such as phytochemicals and probiotics for controlling coccidiosis as well as mitigating the deleterious effects of coccidial infections in production. In this review, we aim to summarize the role, mechanisms, and therapeutic potential of natural products in the treatment of coccidiosis to lay a theoretical foundation for effective coccidiosis control.

Effects of Eimeria challenge on growth performance, intestine integrity, and cecal microbial diversity and composition of yellow broilers

The invasion of Eimeria causes damage to the intestinal barrier, nutrient leakage, and microbial imbalance in poultry. We aimed to investigate the effects of Eimeria infection on growth performance, intestinal integrity, and cecal microbial diversity and composition of yellow broilers. A total of 180 male yellow broilers were randomly divided into an unchallenged control and an Eimeria challenge treatment group within 18 floor pens (10 chicks/pen, 9 replicate pens/group). On day 10, 90 chicks received a cocktail of E. maxima, E. acervulina, and E. tenella oocysts (105/chick) to induce coccidial infection, and the other 90 received an aliquot of PBS. The Eimeria challenge resulted in increased bird feed consumption and FCR from day 11 to 21 (all P < 0.01). Higher fecal Eimeria counts, duodenal, jejunal, and cecal lesions were observed in the challenge group on day 12, 15, 15, 18 respectively (all P < 0.05). Furthermore, the infected birds had larger livers and small intestines, deeper villus crypt, and decreased expression of Claudin-1 on day 21 (all P < 0.05). The 16S rRNA sequencing indicated that alpha diversity (Sobs, Shannon, Simpson, Ace, or Chao) of cecal microbials was not affected by Eimeria challenge (all P > 0.05). However, the PCoA and LEfSe analyses indicated that the Eimeria challenge altered microbial distribution by decreasing the abundance of Firmicutes and enriching the abundance of Proteobacteria at the phylum level. At the genus level, Clostridia vadin BB60 and Lachnospiraceae NK4A136 group were reduced, while Escherichia-Shigella were enriched in the challenged yellow broilers (all P < 0.05). Correlation analyses demonstrated that the birds with higher Lachonospiraceae NK4A136 group and Clostridia vadin BB60, and lower Escherichia-Shigella in their cecal content gained more BW and reached a lower FCR from day 11 to 21 (all P < 0.05). In conclusion, Eimeria infection compromised feed efficiency of yellow broilers by damaging intestinal barrier and shifting cecal microbiota towards colonizers associated with poor performance. Restoring the dysbiotic microbiome could be a potential strategy for improving feed efficiency in yellow broilers under coccidial challenge.

Neutrosophic set and optimized deep learning for classification of chicken Eimeria species: a practical solution for poultry industry

AbstractTo optimize infection control and bolster productivity within the poultry industry, it is imperative to accurately classify Chicken Eimeria species. There are several methods for determining Eimeria disease in chickens. Traditional methods involve watching for clinical symptoms, and macroscopic lesions, and studying the parasite’s biology and oocyst morphology. These methods are frequently time-consuming and labor-intensive, necessitating the manual collection and analysis of samples, which can be especially difficult in large chicken farms. Deep learning algorithms, on the other hand, provide automated, accurate, and non-invasive methods for the detection of Eimeria. This paper proposed a classification model for the automatic classification of chicken Eimeria species. The proposed model is mainly based on integrating neutrosophic set theory and InceptionV3 deep-learning architecture. Three primary phases make up the proposed chicken Eimeria species classification model: the data preprocessing phase, the neutrosophic image conversion phase, and the image classification phase. To address the issue of class imbalance in the adopted dataset and enhance the model’s generalizability, the random oversampling method, and data augmentation techniques are employed during the data preprocessing phase. The preprocessed data is considered to feed the neutrosophic set-based segmentation algorithm, where true, false, and intermediate subsets are extracted. Finally, the true subset is utilized to feed the optimized InceptionV3. To determine the optimal hyperparameter values for InceptionV3, a modified version of the Brown Bear optimization algorithm is proposed in this paper. To evaluate the effectiveness of the proposed model, a real benchmark dataset comprising images of different Eimeria species is adopted. The experimental results revealed that the proposed model offers a more efficient and accurate alternative to traditional methods and state-of-the-art models, enabling faster and more effective diagnosis and treatment of Eimeria infections. It achieved an overall accuracy, specificity, sensitivity, and F1-score of nearly 100%. Additionally, the results showed that the high performance of the proposed model can reduce labor costs and boost throughput, thereby enhancing economic viability even more.

Advanced chelate technology-based trace minerals reduce inflammation and oxidative stress in Eimeria-infected broilers by modulating NF-kB and Nrf2 pathways

This study investigated the effects of substituting inorganic trace minerals (ITM) with advanced chelate technology-based TM (ACTM) in broiler chicken feed on productive performance, metabolic profile, humoral immunity, antioxidant status, and modulation of NF-kB and Nrf2 signaling pathways in mixed Eimeria species exposure. The study involved 480 newly hatched male broiler chickens, which were divided into 5 treatment groups, each with 6 replicate cages and 16 chickens per replicate. The experimental treatments included an uninfected negative control group fed a basal diet with recommended inorganic TM levels (NC), an infected positive control group fed the same diet (PC), a PC group supplemented with salinomycin (SAL), and two PC groups in which the basal diet was replaced with 50% and 100% ACTM instead of inorganic TM (ACTM50 and ACTM100, respectively). All groups, except for the NC group, were orally challenged with mixed Eimeria species oocysts on day 14. According to the results, the PC group showed lower feed intake, breast yield, low-density lipoprotein-cholesterol concentration, lactobacillus spp. counts, and serum IgG levels, but higher jejunal TGF-β expression versus the NC group. The broilers in the NC, SAL, and ACTM100 groups showed higher body weight gain, carcass yield, and TGF-β expression, but lower serum alkaline phosphatase activity, ileal E. coli count, and jejunal expression levels of IL-1β, IL-6, IFN-γ, Nrf2, and SOD1 compared to the PC group, with the NC group having the highest body weight gain and lowest IL-1β and Nrf2 expression levels. Furthermore, the administration of ACTM100 treatment improved feed efficiency, increased serum iron, zinc, manganese, and copper levels, enhanced total antioxidant capacity and different antioxidant enzyme activities, and reduced malondialdehyde concentration. In conclusion, complete replacement of ITM with ACTM effectively protects broilers from Eimeria infection, with similar positive effects to SAL treatment in terms of productive performance and anti-inflammatory responses and better antioxidant responses and mineral availability.

Comparison of the effect of anticoccidial drug, probiotic, synbiotic, phytochemicals and vaccine in prevention and control of coccidiosis in broiler chickens challenged with Eimeria spp

The objective of this study was to investigate the effects of an anti-coccidiosis drug, vaccine, probiotic, symbiotic, and phytochemicals in the prevention and control of coccidia infection in broilers. A total of 525 one-day-old Ross 308 chicks were randomly allocated to 7 experimental diets with 5 replicates of 15 birds each in a completely randomized design. Experimental diets consisted of negative control (NC) without any additives and not challenged. The other 6 groups were challenged with mixed Eimeria and fed the basal diet with no additives (Positive Control, PC) or supplemented with Coxidine 100 (1 g / 1 kg), probiotic, synbiotic, Livacox T vaccine and phytobiotic additives based on the manufacturer's recommended dose. Body weight gain (WG), feed intake (FI) and feed conversion ratio (FCR) were recorded weekly. Oocysts per gram of excreta (OPG) were determined on d 25 to 33 and 42. One bird per cage was euthanized to analyze lesion score and jejunum and ileum inflammatory genes expression. Coccidial challenge reduced WG (P < 0.05) during 15 to 28 d and vaccine treatment was more effective in improving WG and FCR on d 29 to 42 and 1 to 42 (P < 0.05) than other treatments. Birds in the PC group had higher (P < 0.05) OPG than NC group for all days and the vaccine treatment resulted in the lowest rate of OPG compared to other treatments (P < 0.05) at 27, 28, 29, 30, 32, and 33 d of age and overall average. Relative mRNA levels of IFN-γ, IL-1β and IL-10 were significantly upregulated among treatments under coccidiosis challenge in jejunum and ileum except for IL-1β expression in the ileum. In conclusion, based on the results of this study the individual characteristics of feed additives for the prevention of coccidiosis can be different depending on the type and source of feed additives, duration, and amount used, levels of oocyst inoculation and Eimeria types.

A Comparison of the Cecal Microbiota between the Infection and Recovery Periods in Chickens with Different Susceptibilities to Eimeria tenella.

To investigate the effect of Eimeria tenella (E. tenella) infection on the cecal microbiota, resistant and susceptible families were screened out based on the coccidiosis resistance evaluation indexes after E. tenella infection. Subsequently, a comparative analysis of cecal microorganisms among control, resistant, and susceptible groups as well as between different periods following the E. tenella challenge was conducted using metagenomic sequencing technology. The results showed that the abundance of opportunistic pathogens, such as Pantoea, Sporomusa, and Pasteurella in the susceptible group and Helicobacter and Sutterella in the resistant group, was significantly higher on day 27 post-inoculation (PI) (the recovery period) than on day 5 PI (the infection period). Additionally, the abundance of Alistipes, Butyricicoccus, and Eubacterium in the susceptible group and Coprococcus, Roseburia, Butyricicoccus, and Lactobacillus in the resistant group showed a significant upward trend during the infection period compared with that in the recovery period. On day 5 PI, the abundance of Faecalibacterium and Lactobacillus was decreased in both the resistant and susceptible groups when compared with that in the control group and was greater in the resistant group than in the susceptible group, while Alistipes in the susceptible group had a relatively higher abundance than that in other groups. A total of 49 biomarker taxa were identified using the linear discriminant analysis (LDA) effect size (LEfSe) method. Of these, the relative abundance of Lactobacillus aviarius, Lactobacillus salivarius, Roseburia, and Ruminococcus gauvreauii was increased in the resistant group, while Bacteroides_sp__AGMB03916, Fusobacterium_mortiferum, Alistipes_sp__An31A, and Alistipes_sp__Marseille_P5061 were enriched in the susceptible group. On day 27 PI, LDA scores identified 43 biomarkers, among which the relative abundance of Elusimicrobium_sp__An273 and Desulfovibrio_sp__An276 was increased in the resistant group, while that of Bacteroides_sp__43_108, Chlamydiia, Chlamydiales, and Sutterella_sp__AM11 39 was augmented in the susceptible group. Our results indicated that E. tenella infection affects the structure of the cecal microbiota during both the challenge and recovery periods. These findings will enhance the understanding of the effects of changes in the cecal microbiota on chickens after coccidia infection and provide a reference for further research on the mechanisms underlying how the intestinal microbiota influence the growth and health of chickens.

Multi-omics analysis reveals regime shifts in the gastrointestinal ecosystem in chickens following anticoccidial vaccination and Eimeria tenella challenge.

Coccidiosis, caused by Eimeria parasites, significantly impacts poultry farm economics and animal welfare. Beyond its direct impact on health, Eimeria infection disrupts enteric microbial populations leading to dysbiosis and increases vulnerability to secondary diseases such as necrotic enteritis, caused by Clostridium perfringens. The impact of Eimeria infection or anticoccidial vaccination on host gastrointestinal phenotypes and enteric microbiota remains understudied. In this study, the metabolomic profiles and microbiota composition of chicken caecal tissue and contents were evaluated concurrently during a controlled experimental vaccination and challenge trial. Cobb500 broilers were vaccinated with a Saccharomyces cerevisiae-vectored anticoccidial vaccine and challenged with 15,000 Eimeria tenella oocysts. Assessment of caecal pathology and quantification of parasite load revealed correlations with alterations to caecal microbiota and caecal metabolome linked to infection and vaccination status. Infection heightened microbiota richness with increases in potentially pathogenic species, while vaccination elevated beneficial Bifidobacterium. Using a multi-omics factor analysis, data on caecal microbiota and metabolome were integrated and distinct profiles for healthy, infected, and recovering chickens were identified. Healthy and recovering chickens exhibited higher vitamin B metabolism linked to short-chain fatty acid-producing bacteria, whereas essential amino acid and cell membrane lipid metabolisms were prominent in infected and vaccinated chickens. Notably, vaccinated chickens showed distinct metabolites related to the enrichment of sphingolipids, important components of nerve cells and cell membranes. Our integrated multi-omics model revealed latent biomarkers indicative of vaccination and infection status, offering potential tools for diagnosing infection, monitoring vaccination efficacy, and guiding the development of novel treatments or controls.IMPORTANCEAdvances in anticoccidial vaccines have garnered significant attention in poultry health management. However, the intricacies of vaccine-induced alterations in the chicken gut microbiome and its subsequent impact on host metabolism remain inadequately explored. This study delves into the metabolic and microbiotic shifts in chickens post-vaccination, employing a multi-omics integration analysis. Our findings highlight a notable synergy between the microbiome composition and host-microbe interacted metabolic pathways in vaccinated chickens, differentiating them from infected or non-vaccinated cohorts. These insights pave the way for more targeted and efficient approaches in poultry disease control, enhancing both the efficacy of vaccines and the overall health of poultry populations.

Phytase, 25-hydroxyvitamin D3 and cocci vaccination to broilers fed a calcium and phosphorus-reduced diet under Eimeria spp. challenge: effects on growth performance and intestinal health

A study evaluated the effects of phytase, 25-hydroxyvitamin D3 (25OHD), and cocci vaccination on broilers fed a diet reduced in calcium (Ca) and available phosphorus (avP) under Eimeria challenge. A total of 840 one-day-old male broilers were assigned to a 2 × 5 factorial arrangement based on cocci vaccination and dietary treatments. Half of the birds were vaccinated against coccidia on d 1, and all birds were orally challenged with Eimeria spp. (sporulated oocysts: 12,500 of E. maxima, 12,500 of E. tenella, and 62,500 of E. acervulina) on d 14. Dietary treatments included: 1) a nutrient adequate diet (PC); 2) a diet reduced by 0.2% in Ca and avP (NC); 3) NC plus 1,500 FTU/kg of phytase (NC+PHY); 4) NC plus 3,000 IU/kg of 25OHD (NC+25OHD); 5) NC with both PHY and 25OHD (NC+PHY+25OHD). SAS was used for data analysis, with significance set at P ≤ 0.05. Pre-infection growth performance was comparable across the treatments. However, vaccinated birds exhibited higher body weight (BW) and body weight gain (BWG) from 0 to 6 d postinoculation (DPI; P < 0.05). The NC diet reduced BWG from 6 to 12 DPI and increased the feed conversion ratio (FCR) during 6 to 12 DPI and the overall period (0-26 d) compared to the PC birds. In contrast, the supplementation with phytase, 25OHD, or both, returned BWG and FCR to levels seen with the PC diet (P < 0.01). Vaccinated birds also had reduced gut permeability at 5 DPI, increased intestinal villus height, and lower expression levels of the tight junction proteins junctional adhesion molecule 2 (JAM2) and occludin (OCLN) at 6 DPI (P < 0.05). Interestingly, the cocci vaccine resulted in lower E. acervulina but higher E. tenella oocyst shedding at 6 DPI (P < 0.01). Interaction effects were observed for duodenal lesion scores and ileal crypt depth at 6 DPI (P < 0.05). In conclusion, coccidial vaccination improved growth performance, decreased intestinal permeability, enhanced intestinal morphology, and modulated tight junction protein gene expression under Eimeria infection. Reducing dietary Ca and avP levels adversely affected growth performance and FI during the recovery phase, but these negative effects could be mitigated by supplementing with phytase or 25OHD.

Dynamic response of the intestinal microbiome to Eimeria maxima-induced coccidiosis in chickens.

We have observed for the first time the dynamic response of the intestinal microbiota to Eimeria maxima infection, synchronized with its life cycle. Minimal changes occur in both the ileal and cecal microbiota during early infection, while significant alterations coincide with acute infection and disruption of the intestinal mucosal lining. As animals recover from coccidiosis, the intestinal microbiota largely returns to normal. E. maxima-induced intestinal inflammation likely creates an environment conducive to the growth of aerotolerant anaerobes such as Lactobacillus, as well as facultative anaerobes such as Escherichia, Enterococcus, and Staphylococcus, while suppressing the growth of obligate anaerobes such as short-chain fatty acid-producing bacteria. These findings expand our understanding of the temporal dynamics of the microbiota structure during Eimeria infection and offer insights into the pathogenesis of coccidiosis, supporting the rationale for microbiome-based strategies in the control and prevention of this condition.

Cross Sectional Study of Poultry Coccidiosis in Adele Poultry Farm, Eastern Hararghe, Oromia, Ethiopia

Objective: This study was to determine the number of chickens in intensively managed poultry farms and to assess the relationship between the number of chickens and risk factors in specific poultry farm. Methods: A cross-sectional study was conducted in Adele town between December 2014 and November 2015. The presence of oocysts in the fecal samples was examine by floatation methods and post-mortem examinations looked for intestinal lesions. Results: Out of the 262 chicken sample sources examined, 29 (11.01%) were positive for coccidian oocysts, and out of the 84 total Environmental sample source examined, 12 (14.4%) were positive for coccidian parasites. There were no statistically significant differences in prevalence across the sample type and source (p greater than 0.05). There were no changes in the prevalence of coccidiosis between the sexes of birds. Pless than 0.05 indicates a statistically significant difference between the age groups. Furthermore, a strong correlation was found between the sample times. The prevalence of coccidia was considerably higher in chicks than in adults (P less than 0.05). The environment had a greater prevalence of coccidiosis than faeces did. Of the environmental samples, the majority of coccidial infections are linked to management issues, and the prevalence of water and feed is higher than that of litter material. Conclusions: This study showed that coccidiosis is a significant disease affecting poultry in the studied area and that effective control measures must be developed to reduce the illness's impact.

Prevalence of opportunistic intestinal coccidian parasites and associated factors in HIV/AIDS patients attending anti-retroviral therapy (ART) clinic at Debre Tabor Comprehensive Specialized Hospital, Northwest Ethiopia: A cross-sectional study.

A growing number of acquired immunodeficiency syndrome (AIDS) patients suffer from opportunistic intestinal coccidian infections. Instead of human immuno deficiency virus (HIV) infection itself, opportunistic infections like intestinal coccidian parasites cause death of over 80% AIDS patients. Factors like exposed drinking water sources and poverty aid the prevalence of opportunistic intestinal coccidian parasitic infections in HIV/AIDS patients. The goal of this study was to determine the prevalence of intestinal coccidian parasites and associated factors in HIV/AIDS patients. A health facility based cross sectional study was conducted from 140 HIV/AIDS patients attending ART clinic in Debre Tabor Comprehensive Specialized Hospital, Northwest Ethiopia from September to December 2023. The sociodemographic characteristics were collected through face-to-face interviews. Stool samples were processed with Modified Acid Fast staining technique. Statistical Package for Social Sciences software version 20 was used to analyze the data. Logistic regression was used to assess factors associated with dependent variable and p < 0.05 was considered significantly associated. The total prevalence of opportunistic intestinal coccidian parasites (OICPs) in HIV/AIDS patients was 16.4% (23/140). Drinking surface water [p = 0.015, COR = 3.4] compared to tape water, drinking alcohol [p = 0.001, COR = 18] compared to not drinking alcohol, diarrhea [p = 0.005, COR = 1] compared to non-diarrheic, drug dropout [p = 0.01, COR = 11] compared to regular drug intake and low CD4 count [p = 0.042, COR = 9] compared to CD4 > 500/µL showed significant association with increased prevalence of OICPs in HIV/AIDS patients. OICPs are still the common causes of morbidity and mortality in HIV/AIDS patients. Surface water consumption, alcoholism, interruption of treatment drugs, diarrhea, and reduced CD4+ T-cells significantly contribute to acquisition and prevalence of OICPs in HIV/AIDS patients. Routine screening of OICPs with sensitive diagnostic techniques in HIV/AIDS patients regardless of symptoms is crucial and has to be practiced in health settings.

Ameliorative Effects of Teucrium polium Leaves Ethanolic Extract on Liver Histopathology Induced by Eimeria papillata

Background: Teucrium polium is an herb utilized in traditional medicine for its biological activity. In the present study, T. polium leaves ethanolic extract (TPLEE) was investigated for its effects on coccidiosis resulting from Eimeria papillata infection in mice. Methods: In vivo, TPLEE (150 mg/kg) was administered for its antioxidant and hepatoprotective properties. The anticoccidial and anti-inflammatory effects of TPLEE were evaluated by measuring oocyst suppression and assessing liver histopathology, respectively. Result: Indicated that treatment with 150 mg/kg TPLEE led to oocyst suppression percentage of 91.2±4.1, similar to the efficacy of the reference drug amprolium (93.2±3.9) and was associated with a significant decrease in the number of developmental parasitic stages in jejunal sections. Infection with the parasite causes metabolic disturbance, inflammation and liver injury, as evidenced by histopathological changes such as Kupffer cell activation, vacuolated hepatocytes and increases in inflammatory cellular infiltration. In addition, infection led to a significant increase in malondialdehyde (MAD) and nitric oxide (NO) and a significant decrease in superoxide dismutase (SOD) and glutathione (GSH). The TPLEE showed significant hepatoprotective ability by improving the above parameters. TPLEE demonstrated both anticoccidial properties and the ability to alleviate preexisting liver damage caused by Eimeria infection.

Effects of DNA Methylation of HPA-Axis Genes of F1 Juvenile Induced by Maternal Density Stress on Behavior and Immune Traits in Root Voles (Microtus oeconomus)-A Field Experiment.

The literature shows that maternal stress can influence behavior and immune function in F1. Yet, most studies on these are from the laboratory, and replicated studies on the mechanisms by which maternal stress drives individual characteristics are still not fully understood in wild animals. We manipulated high- and low-density parental population density using large-scale field enclosures and examined behavior and immune traits. Within the field enclosures, we assessed anti-keyhole limpet hemocyanin immunoglobulin G (anti-KLH IgG) level, phytohemagglutinin (PHA) responses, hematology, cytokines, the depressive and anxiety-like behaviors and prevalence and intensity of coccidial infection. We then collected brain tissue from juvenile voles born at high or low density, quantified mRNA and protein expression of corticotropin-releasing hormone (CRH) and glucocorticoid receptor gene (NR3C1) and measured DNA methylation at CpG sites in a region that was highly conserved with the prairie vole CRH and NR3C1 promoter. At high density, we found that the F1 had a lower DNA methylation level of CRH and a higher DNA methylation level of NR3C1, which resulted in an increase in the expression levels of the CRH mRNA and protein expression and further reduced the expression levels of the NR3C1 mRNA and protein expression, and ultimately led to have delayed responses to acute immobilization stress. Juvenile voles born at high density also reduced anti-KLH IgG levels and PHA responses, increased cytokines, and depressive and anxiety-like behaviors, and the effects further led to higher coccidial infection. From the perspective of population density inducing the changes in behavior and immunity at the brain level, our results showed a physiological epigenetic mechanism for population self-regulation in voles. Our results indicate that altering the prenatal intrinsic stress environment can fundamentally impact behavior and immunity by DNA methylation of HPA-axis genes and can further drive population fluctuations in wild animals.

Metabolomic analysis reveals altered amino acid metabolism and mechanisms underlying Eimeria infection in laying hens

Avian coccidiosis, caused by Eimeria spp, is a devastating disease in laying hens. Previous studies have suggested that amino acids may be involved in Eimeria infection of broiler chickens. However, their metabolic features in laying hens, as well as the effect of multiple Eimeria species challenges on poultry hosts have not been elucidated yet. Here, a targeted metabolomics approach was employed to identify altered amino acid metabolism and mechanisms in laying hens with multiple Eimeria species challenges. Laying hens, Hy-Line W-36 aged 25 wk, were randomly assigned to a control group and groups inoculated with varying levels of mixed Eimeria species (E. maxima, E. tenella, and E. acervulina). Serum samples from each group were collected at 6 d and 14 d of postinoculation (6 and 14 DPI) for metabolite profiling. Metabolomic analysis revealed notable metabolic variations between control and infected groups, especially at 6 DPI stage. Varying levels of Eimeria dosages did not show a significant metabolic difference, and metabolites were sensitive to low-level infection. With statistical analysis, differentially expressed compounds (3-methylhistidine, alanine, aspartate, lysine, asparagine, methionine, ornithine, and tryptophan) were selected, and their metabolic network was identified by pathway enrichment analysis. In the network, the lysine biosynthesis pathway was upregulated, while the arginine and proline metabolic pathway was downregulated under infection. Other pathways showed complex patterns of metabolic relationships. Based on the results, biological implications of metabolic changes were elucidated and discussed. Last, the results were further confirmed with our previous study (phenotype and gene expression results) using the same set of samples. Our finding provides in-depth information on altered amino acid metabolism and mechanisms in laying hens upon multiple Eimeria species infection.

Habitat-induced changes in forage quality and implications for fitness in Plateau Pika (Ochotona curzoniae)

Abstract Plateau pikas (Ochotona curzoniae) play a keystone role in the alpine meadow ecosystem on the Qinghai–Tibetan Plateau (QTP). For decades, QTP grasslands have become degraded to some degree, largely as a result of heavy livestock grazing. Concomitantly, the abundance of plateau pikas has increased dramatically as grassland degradation has altered the vegetation community structure and dominant species, shifting the plant nutrient contents toward higher protein conditions that favor them. Considerable research supports the hypothesis that the quantity and quality of food limit herbivore populations. Here, we examined the relationship between the availability of essential amino acids in the diets of plateau pikas and the degree of meadow degradation associated with livestock grazing intensity through a field survey, as well as the fitness of individuals by laboratory feeding experiments with 2 pelleted chows containing 0.26% and 0.45% methionine. Sulfur-containing methionine and cystine were the most limiting amino acids in the diets of pikas. During the pika breeding season, the concentrations of most essential acids, particularly methionine and cystine, were higher in heavily degraded meadows than in lightly and moderately degraded meadows. Individuals fed 0.45% methionine exhibited enhanced cell-mediated immunity, reduced intensity of coccidian infection, and increased concentrations of gonadotropin-releasing hormone, luteinizing hormone, estradiol, progesterone, and testosterone compared to those fed 0.26% methionine. These results showed that heavily degraded meadows provided relatively high-quality food that improved individual fitness, suggesting that the high-methionine food in the heavily degraded meadows may be a key factor in the generation and maintenance of high-density populations of plateau pikas.

Clinicopathology and Ultrastructural Alterations of Experimentally Induced Necrotic Enteritis in Chickens

Background: This study was designed to elucidate the clinicopathological and ultrastructural alterations in experimentally induced necrotic enteritis (NE) in chickens and the present study acknowledged pronounced clinical signs, gross, histopathological and ultrastructural lesions in the chickens infected by both Clostridium perfringens type A, type C and coccidia infection. Methods: The day-old chickens were divided in to five groups including control. NE was induced by Clostridium perfringens, type-A and C with and without coccidia infection to the designated experimental groups in this study. Result: The clinical signs, hematology and biochemical parameters were evaluated in this study. Clinical indicators included diarrhea, ruffled feathers, dehydration, depression and a drop in TEC, Hb% and PCV% were noticeable. There was also a large increase in TLC and DC, a significant increase in ALT, AST and a decrease in total protein. In the intestine and other organs, there were noticeable inflammatory gross lesions and histological lesions. Transmission electron microscopic (TEC) observation of intestine revealed disruption of intercellular junction complexes, delimitation of enterocytes, disintegration of nucleus, dilatation of endoplasmic reticulum and cristeolysis of mitochondria. The present work will be an admiring contribution to inclusive study of the NE in chicken in terms of clinicopathology and ultrastructural lesions.

Efficacy of liver free and Chitosan against Eimeria tenella in chickens

Eimeria spp. are the pathogen that causes coccidiosis, a significant disease that affects intensively reared livestock, especially poultry. Anticoccidial feed additives, chemicals, and ionophores have routinely been employed to reduce Eimeria infections in broiler production. Therefore, the shift to antibiotic-free and organic farming necessitates novel coccidiosis preventive strategies. The present study evaluated the effects of potential feed additives, liver free and chitosan, against Eimeria tenella infection in White Leghorn broiler female chickens. One hundred sixty-five 1-day-old White Leghorn broiler female chicks were divided into 11 groups (15 female chicks per group), including the positive control group (G1), the negative control group (G2), a chitosan-treated group (G3), a chitosan-treated-infected group (G4), the liver free-treated group (G5), the liver free-treated-infected group (G6), the liver free-and-chitosan-treated group (G7), the liver free-and-chitosan-infected group (G8), the therapeutic liver free-and-chitosan-treated-infected group (G9), the sulfaquinoxaline-treated group (G10), and the sulfaquinoxaline-treated-infected group (G11). Chitosan was fed to the chicks in G3 and G4 as a preventative measure at a dose of 250 mg/kg. The G5 and G6 groups received 1.5 mg/kg of Liverfree. The G7 and G8 groups received chitosan and Liverfree. The G10 and G11 groups were administered 2 g/L of sulfaquinoxaline. From the moment the chicks arrived at Foshan University (one-day-old chicks) until the completion of the experiment, all medications were given to them as a preventative measure. G8 did; however, receive chitosan and liver free as therapeutic supplements at 7 dpi. The current study showed that the combination of liver free and chitosan can achieve better prophylactic and therapeutic effects than either alone. In E. tenella challenged chickens, G8 and G9 chickens showed reduced oocyst shedding and lesion score, improved growth performance (body weight, body weight gain, feed intake, feed conversion ratio, and mortality rate), and cecal histology. The current study demonstrates that combining liver free and chitosan has superior preventive and therapeutic benefits than either alone, and they could also be used as alternative anticoccidial agents.

Anticoccidial activity of the secondary metabolites in alpine plants frequently ingested by wild Japanese rock ptarmigans

The Japanese rock ptarmigan (Lagopus muta japonica) is an herbivorous species of partridges that inhabits only alpine zones. Alpine plants are their main source of food. These alpine plants contain toxic compounds to deter herbivores from consuming them. A previous analysis of the alpine plants frequently consumed by Japanese rock ptarmigans revealed the presence of a unique mixture of secondary metabolites and a novel compound. Additionally, wild Japanese rock ptarmigans are often infected by two species of Eimeria parasites. When these parasites were experimentally administered to Svalbard rock ptarmigans (Lagopus muta hyperborean), which do not feed on alpine plants, the birds exhibited symptoms, such as diarrhea and depression, and in some cases, they died. Although little is known about the pathogenesis of these parasites in wild Japanese rock ptarmigans, it was hypothesized that compounds found in alpine plants, their main food source, may reduce the pathogenicity of Eimeria parasites. In the present study, we evaluated the anticoccidial activity of the compounds derived from alpine plants in vitro using Eimeria tenella, which infects chickens belonging to the same pheasant family, as an experimental model. Twenty-seven natural components were extracted from eight alpine plants. The natural components were added to E. tenella sporozoites and incubated for 24 h to evaluate their direct effect. Additionally, Madin-Darby bovine kidney cells were incubated with sporozoites and natural components for 24 h to evaluate the inhibitory effect of the components on sporozoite cell invasion. Six compounds from four alpine plants decreased sporozoite viability by up to 88.3%, and two compounds inhibited sporozoite invasion into the cells. Although further studies are needed to evaluate the effects of these components against Eimeria infections in vivo, our findings suggest that these alpine plants may reduce the degree of infection by decreasing the number of sporozoites in the intestinal tract.

Effect of feeding a blackseed meal-sericea lespedeza leaf meal pellet on gastrointestinal nematode and coccidia infection and animal performance in young goats

Gastrointestinal nematode (GIN) infection poses the most significant obstacle to the sustainable development of small ruminant (sheep and goat) farming globally. Resistance of GINs to synthetic anthelmintic drugs has led to rising interest in exploring alternative methods for parasite control, such as the utilization of bioactive plants with anti-parasitic properties. In this investigation, black seed (Nigella sativa), a shrub high in secondary antioxidant compounds, and sericea lespedeza (Lespedeza cuneata), a perennial legume high in tannins with anti-parasitic properties were combined to determine if two bioactive plants containing different types of secondary compounds can provide a stronger anti-parasitic effect than sericea lespedeza alone. In a 49-day trial, naturally parasitized 6–7-month-old intact male Spanish goats (n = 15/treatment) were fed pelletized feeds encompassing sericea lespedeza leaf meal (SL), a combination of black seed meal (BS) and sericea lespedeza leaf meal (BS-SL - 75 % SL, 25 % BS), or alfalfa (Medicago sativa, control parasitized; CONP), with an additional group of dewormed kids given the alfalfa pellets (Control treated; CONT). Weekly measurements of animal weights and samples of blood and feces were collected to determine the packed cell volume (PCV), GIN fecal egg counts (FEC), and coccidia fecal oocyte counts (FOC), respectively. All animals were processed at the end of the trial (60 total), with adult Haemonchus contortus worms recovered from the abomasum of each goat for counting and sex determination. Carcass weights were recorded after processing. Goats given the SL and BS-SL treatments had lower FEC (P<0.05) than the parasitized alfalfa (CONP) goats. At the end of the study, the SL and BS-SL groups' FOC values were lower (P < 0.05) than the CONT and CONP groups. A rise in PCV values was seen over time for all groups; SL, BS-SL, and CONT animals exhibited higher PCV values (P < 0.05) in comparison to the CONP goats. The parasitized goats fed SL-only pellets showed greater feed intake and animal body weights (P < 0.05) compared to goats fed BS-SL or alfalfa pellets. However, the treatments had no effect on the weight of the goats' carcasses. Although the H. contortus adult worm counts in the CONT goats (alfalfa-dewormed) were lower (P < 0.05) than in the CONP goats (alfalfa-parasitized), they did not differ from the SL or BS-SL animals. This study indicates that sericea lespedeza leaf meal pellet diet, either by itself or in combination with black seed meal, showed promising results as an anthelmintic and may prove to be an effective alternative to exclusive use of conventional deworming drugs. The addition of black seed did not appear to enhance the effectiveness of sericea lespedeza in this study.

Impacts of a highly pathogenic ovine Eimeria ovinoidalis on the growth of Hu lambs

The apicomplexan Eimeria ovinoidalis is distributed worldwide. It can cause clinical coccidiosis, which is one of the most pathogenic species in sheep, reducing growth rates and resulting in significant economic losses in the industry. Its principal clinical sign is profuse diarrhoea in young animals. In this study, we established a model of E. ovinoidalis infection in lambs to understand its pathogenicity and evaluate the gut microbiota and fecal metabolite profiles. Specifically, we observed a significant shift in the abundance of bacteria and disrupted metabolism in lambs. Especially during the peak period of excrete oocysts, it promoted the reproduction of some harmful bacteria in Proteobacteria and Actinobacteriota, and reduced the abundance of beneficial bacteria such as Lachnospiraceae and Rikenellaceae. In the later stage of the patent period, the abundance of harmful bacteria in the intestine decreased, the abundance of beneficial bacteria which could produce anti-inflammatory substances began to increase, and the abundance and diversity of intestinal flora also tended to parallel with the control group. Coccidia infection could lead to the increase of differential metabolites and metabolic pathways between infected and control group, but the difference decreased with time. During the peak period of excrete oocysts, although the antimicrobial metabolites such as Lividamine were up-regulated, the excess of these metabolites could still induce the production of endotoxin, while Butanoic acid and other anti-inflammatory metabolites decreased significantly. A metabolomics analysis showed that E. ovinoidalis infection altered metabolites and metabolic pathways, with biosynthesis of unsaturated fatty acids, Teichoic acid biosynthesis and Butanoate metabolism as the major disrupted metabolic pathways. Details of the gut microbiota and the metabolome after infection with E. ovinoidalis may aid in the discovery of specific diagnostic markers and help us understand the changes in parasite metabolic pathways.