Supplementing broiler diets with bacterial selenium nanoparticles enhancing performance, carcass traits, blood indices, antioxidant status, and caecal microbiota of Eimeria tenella-infected broiler chickens

Nanomedicine is a critical therapeutic approach for treating most poultry illnesses, particularly parasitic infections. Coccidiosis is a severe protozoan infection affecting poultry; the emergence of drug-resistant Eimeria strains demands the development of new, safe therapies. Consequently, the objective of this work was to investigate the efficacy of the biosynthesized selenium nanoparticles (SeNPs) by Paenibacillus polymyxa (P. polymyxa) against Eimeria tenella (E. tenella) experimental infection in broiler chickens. The prepared SeNPs absorbed the UV at 270 nm were spherical with a size of 26 nm, and had a surface negative charge of -25 mV. One hundred and fifty, 1-day-old male broiler chicks were randomly allocated into 5 groups (30 birds/group with triplicates each) as follows: T1: negative control (noninfected and nontreated with SeNPs); T2: delivered SeNPs (500 µg/kg diet) for 35 successive days, T3: E. tenella-infected (positive control birds), T4: E. tenella-infected and treated with SeNPs (500 µg/kg diet) and T5: E. tenella-infected chicks and treated with anticoccidial agent (sulfadimidine, 16% solution 8 mL/L of drinking water) for 5 successive days. At 14 d of age, each bird in infected groups was orally treated with 3 × 103 sporulated oocyst of E. tenella. SeNPs considerably decreased the number of oocysts in broiler feces compared to positive control and anticoccidial drug, followed by a substantial reduction of parasite phase count in the cecum (15, 10, and 8 for meronts, gamonts, and developing oocysts) when compared with positive control birds. The Eimeria experimental infection lowered the activity of antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidase (GPx), and reduced glutathione (GSH) while increasing the stress parameters nitric oxide (NO) and malonaldehyde (MDA). Moreover, the production of proinflammatory (TNF-α and IL-6) and apoptotic genes (BcL2 and Cas-3) were significantly elevated. Administrating SeNPs to chicks significantly decreased oxidative stress, inflammation, and apoptotic markers in the cecum tissue. Therefore, growth performance, carcass weights, antioxidant enzymes, and blood properties of infected chicks were enhanced. The findings compared the protecting role of Se-nanoparticles against cecum damages in E. tenella-infected broilers.

Potential of Spirulina platensis as a feed supplement for poultry to enhance growth performance and immune modulation

Increase in drug resistance as well as ineffective immunization efforts against various pathogens (viruses, bacteria and fungi) pose a significant threat to the poultry industry. Spirulina is one of the most widely used natural ingredients which is becoming popular as a nutritional supplement in humans, animals, poultry and aquaculture. It contains protein, vitamins, minerals, fatty acids, pigments, and essential amino acids. Moreover, it also has considerable quantities of unique natural antioxidants including polyphenols, carotenoids, and phycocyanin. Dietary supplementation of Spirulina can beneficially affect gut microbial population, serum biochemical parameters, and growth performance of chicken. Additionally, it contains polyphenolic contents having antibacterial effects. Spirulina extracts might inhibit bacterial motility, invasion, biofilm formation, and quorum sensing in addition to acting directly on the bacterium by weakening and making the bacterial cell walls more porous, subsequently resulting in cytoplasmic content leakage. Additionally, Spirulina has shown antiviral activities against certain common human or animal viruses and this capability can be considered to exhibit potential benefits against avian viruses also. Spirulan, a calcium-rich internal polysaccharide of Spirulina, is potentially responsible for its antiviral effect through inhibiting the entry of several viruses into the host cells, boosting the production of nitric oxide in macrophages, and stimulating the generation of cytokines. Comparatively a greater emphasis has been given to the immune modulatory effects of Spirulina as a feed additive in chicken which might boost disease resistance and improve survival and growth rates, particularly under stress conditions. This manuscript reviews biological activities and immune-stimulating properties of Spirulina and its potential use as a dietary supplement in poultry to enhance growth, gut health and disease resistance.

A century of "anticoccidial drugs": bibliometric analysis

Publications are an important measure of scientific and technological progress. The quantitative examination of the number of publications in a certain research topic is known as bibliometrics. Bibliographic studies are widely used to analyse the condition of research, future potential, and current growth patterns in a certain topic. It can serve as a basis for making decisions and implementing strategies to achieve long-term development goals. To our knowledge, no research has been conducted in these domains; so, this work aims to employ bibliometric analysis to provide comprehensive data on publications related to anticoccidial drugs. As a result, the current study uses bibliometric analysis to track the evolution of anticoccidial drugs and its consequences in the academic and public worlds via a survey of relevant scientific and popular publications. The Dimensions database was used to retrieve the bibliographical statistics, which were then cleaned and analyzed. The data was also loaded into the VOS viewer, which generated a network visualization of the authors with the most joint articles. The investigation discovered three stages of publications and citations since the first article on anticoccidial drugs in 1949. The first stage, which ran from 1920 to 1968, was characterized by a scarcity of research articles on anticoccidial drugs. From 1969 to 2000, the second stage was marked by a stable and marginally increased number of articles. The scientific field was characterized by an increasing trend in the number of publications and their citations from 2002 to 2021. The study gave a complete list of the top anticoccidial drugs funding agents, countries, research institutes, most cited publications, and important co-authorship and partnerships. The outcomes of the study will help veterinary practitioners and researchers understand the trends and best sources of knowledge in the field of anticoccidial medications.

In Vitro Antioxidant, Antimicrobial, Anticoccidial, and Anti-Inflammatory Study of Essential Oils of Oregano, Thyme, and Sage from Epirus, Greece

Origanum vulgare subsp. hirtum, Thymus vulgaris, and Salvia fructicosa are aromatic plants commonly found in Mediterranean countries and are traditionally used in Greece as a remedy for humans, since they are well known as potent antibacterial, antioxidant, and anti-inflammatory agents. Essential oils (EOs) derived from plants cultivated in the mountainous region of Epirus, Greece, were investigated for their inhibitory activity against key microorganisms with relevance to avian health, while also assessing their antioxidant and anti-inflammatory activity. The total phenolic content (TPC) of the EOs was estimated according to the Folin−Ciocalteu method, while the antioxidant capacity was tested through the EOs’ ability to scavenge free radicals by means of the DPPH, ABTS, and FRAP assays. Antibacterial and anti-inflammatory effects were examined by the agar disc diffusion method and the lipoxygenase (LOX) inhibition test, respectively. Furthermore, the EOs’ ability to inhibit the invasion of sporozoites of Eimeria tenella (Wisconsin strain) along with any toxic effects were assayed in Madin−Darby bovine kidney (MDBK) cells. The antioxidant activity of the EOs was observed in descending order: oregano > thyme > sage. The antimicrobial effects of thyme and oregano were equivalent and higher than that of sage, while the anti-inflammatory effect of thyme was higher compared to both sage and oregano. The intracellular invasion of sporozoites was evaluated by the detection of E. tenella DNA by qPCR from cell monolayers harvested at 2 and 24 h post-infection. Parasite invasion was inhibited by the addition of oregano essential oil at the concentration of 100 μg/mL by 83% or 93% after 2 or 24 h, respectively, and was higher compared to the addition of thyme and sage, which had similar effects, but at a less intensive level. The cytotoxic assessment of all three essential oils revealed that they had no effect on MDBK cells compared to dimethyl sulfoxide (DMSO), used as the control substance. The supplementation of oregano, thyme, and sage essential oils had a potent antioxidant, anti-inflammatory, antimicrobial, and anticoccidial in vitro effect that is comparable to synthetic substances or approved drugs, justifying the need for further evaluation by in vivo studies in broilers reared in the absence of antimicrobial and anticoccidial drugs or synthetic antioxidant and/or anti-inflammatory compounds.

In Vitro Study to Evaluate the Efficacy of Ultrasonicated Ethanolic Extract of Rosmarinus officinalis and its Chitosan-Based Nanoparticles Against Eimeria tenella Oocysts of Chickens

In this study, chitosan nanoparticles (CsNPs) were used as nanocarrier for ultrasonicated ethanolic extract of Rosmarinus officinalis (UEERO) as a new nanoformulation against Eimeria tenella. Herein, CsNPs have been synthesized by ionic gelation method at pH 3 (CsNPs3) and pH 5 (CsNPs5), followed by characterization of morphology, size, polydispersity index (PDI), surface charge, and loading efficiency of UEERO. An in vitro sporulation inhibition assay (10, 5, 2.5, 1.25, 0.62, 0.31, 0.15, 0.07, 0.04, 0.02, and 0.01 mg/ml normal saline solution) against E. tenella was conducted. Results showed that free CsNPs and UEERO-CsNPs3/5 were cubic- and spherical-shaped with positive charge and average size of ~ 150.8 nm (314.4 nm) and 151.7 nm (321.1 nm), respectively. The total loading efficiency using UV–vis spectrophotometer, was 80.05 at pH 5 and 64.39% at pH 3. The in vitro sporulation inhibition assay revealed that UEERO, CsNPs3/5, and UEERO-CsNPs3/5 showed a potential inhibitory effect on sporulation (%), distortion in wall (%), and sporocyst abnormality (%) in a dose-dependent manner. Accordingly, the concentration (10 mg/ml) showed the best efficacy after 24 h in UEERO, free CsNPs, and UEERO-CsNPs. Moreover, UEERO-CsNPs3 and UEERO-CsNPs5 had stopped the sporulation (%) after 72 h. Taken all together, UEERO-CsNPs3 and UEERO-CsNPs5 are best effective against E. tenella in a dose-dependent manner in terms of sporulation (%), distortion in wall (%), and sporocysts abnormality.

Use of Zinc Oxide Nanoparticles as Anticoccidial Agents in Broiler Chickens along with Its Impact on Growth Performance, Antioxidant Status and Hematobiochemical Profile

The impact of zinc oxide nanoparticles (ZnO-NPs) on the pathogenesis of coccidiosis in broiler chickens was tested. A total of 160 1-day-old broiler chicks (Ross 308) were randomly allocated into 4 groups (n = 40). Group 1: unchallenged, unmedicated; Group 2: challenged, unmedicated; Group 3: challenged, supplemented with diclazuril (1 ppm); Group 4: challenged, supplemented with ZnO-NPs (20 ppm). Mixed Eimeria species (E. maxima, E. acervulina, E. mivati, and E. tenella) of a commercial coccidial vaccine (FORTEGRA®) were used to perform the coccidial challenge by 15× of its vaccinal dose on the 14th day of age. Diclazuril and ZnO-NPs supplementation in Group 3 and 4, respectively, reduced the mortality rate due to coccidial challenge to 5.8% compared to 11.9% in Group 2. The growth performance was improved by ZnO-NPs in coccidiosis-infected group (p ≤ 0.05) compared to Group 2 and was comparable to that of Group 3 (p ≥ 0.05). The average oocyst count was lower in Groups 3 and 4 (7.8 × 103 and 14.3 × 103, respectively) than in Group 2 (67 × 103 oocysts). Group 3 had a decreased gross lesion score in duodenum and caecum (p ≤ 0.05) as well as jujenum and ileum (p ≥ 0.05) compared to Group 2; while the average lesion scores of all intestinal parts in Group 4 were significantly decreased (p ≤ 0.05). However, diclazuril was superior to ZnO-NPs in reducing caecal lesion score (p ≤ 0.05). Plasma carotenoids levels were increased by diclazuril (p ≥ 0.05) and ZnO-NPs (p ≤ 0.05) supplementation compared to Group 2. Oxidative stress appeared on the fourth week post-challenge (pc) in Group 2 (p ≤ 0.05) compared to Group 1, while the dietary supplementation with either diclazuril or ZnO-NPs numerically decreased Malondialdhyde (p ≥ 0.05) and statistically increased antioxidant activity (p ≤ 0.05). Both medications significantly improved the PCV%, Hb% and RBCs count on the 6th-day and 4th-week pc (p ≤ 0.05) compared to Group 2, though this improvement was higher significantly in Group 4 than Group 3 on the 6th day pc (p ≤ 0.05). Neither coccidial challenge nor medications had an impact on the total WBCs count as well as organ index, except Bursa of fabricious index that significantly improved by ZnO-NPs on the 4th-week pc compared to Group 2. Coccidial challenge reduced total protein and globulin levels and increased the serum alanine aminotransferase, serum cholesterol, and low-density lipoprotein levels (p ≤ 0.05) compared to Group 1, while those of both medicated groups (Group 3 and 4) were comparable to Group 1 (p ≥ 0.05). In conclusion, ZnO-NPs were found to be as effective as diclazuril against coccidiosis. However, further research is needed to fully comprehend its anticoccidial mechanisms.

S-Methylcysteine Ameliorates the Intestinal Damage Induced by Eimeria tenella Infection via Targeting Oxidative Stress and Inflammatory Modulators

Avian coccidiosis is one of the major parasitic diseases in the poultry industry. The infection is caused by Eimeria species, and its treatment relies mainly on the administration of anticoccidial drugs, which can result in drug resistance and side effects. The recent trends in avian coccidiosis treatment is directed to the development of a new therapy using herbal compounds. S-Methylcysteine (SMC) is considered one of the organosulfur compounds in garlic that showed promising activity in the treatment of different pathological conditions via a wide range of anti-inflammatory and antioxidant mechanisms. In this study, the anticoccidial activity of SMC was investigated in Eimeria tenella-infected chickens compared to diclazuril as a widely used anticoccidial drug. In this regard, 14-day-old broilers were divided into six groups (n = 18). The first group (G1) was the healthy control group, while the second group (G2) was the non-infected SMC group treated at a dose of 50 mg/kg b.w. (high dose). Moreover, the third group (G3) was the positive control group (infected and non-treated). The fourth group (G4) was the infected group treated with SMC of 25 mg/kg b.w. (low dose), while the fifth group (G5) was the infected group treated with SMC of 50 mg/kg b.w. (high dose). Conversely, the sixth group (G6) was the diclazuril-treated group. The anticoccidial effects of SMC and diclazuril were evaluated by counting oocysts and recording the body weight gain, feed conversion ratio, clinical signs, lesions, and mortality rate. Interestingly, SMC showed potent anticoccidial activity, which was exemplified by reduction of oocyst count. Furthermore, the biochemical, antioxidant, and anti-inflammatory parameters in the cecal tissues were restored toward their control levels in G4, G5, and G6. Histopathological observation of cecal tissues was consistent with the aforementioned results revealing the ameliorative effect of SMC against E. tenella infection. This study concluded novel findings in relation to the anticoccidial role of SMC as a plant-based compound against the E. tenella-induced coccidiosis in broiler chickens combined with its antioxidative and anti-inflammatory properties. Further studies for exploring the mechanistic pathways involved in this activity and the potential benefits from its use in association with conventional anticoccidial drugs are warranted.

Anticoccidial Drug Sensitivity of Eimeria Contained in Live Coccidia Vaccines of Broilers, Breeders, and Turkeys

Extensive usage and the limited number of approved poultry anticoccidial drugs has led to some degree of resistance being developed to all drugs. Three independent battery trials were conducted to evaluate the anticoccidial drug sensitivity (AST) of species/strains of Eimeria within three commercial coccidia vaccines. The vaccines used for these studies were Immucox 3^® (broiler vaccine) (IM3), Immucox 5^® (broiler breeder vaccine) (IM5), and Immucox T^® (turkey vaccine) (IMT). Each trial used a randomized block design with six replications. Each cage contained eight male Cobb 500 broilers (IM3 and IM5) or eight male Hy-Line turkeys (IMT). At 12 days of age (D0), birds were group weighed, allocated to treatment cages, and issued weighed treatment feeds. Birds and remaining feed were weighed on D8 (20 days of age) (IM3 and IM5) or D9 (21 days of age (IMT)). Anticoccidial drugs were blended at commercial use levels. The treatments were as follows. IM3: 1) Nonmedicated nonchallenged (NMNC); 2) Nonmedicated challenged (NMC); challenged and medicated with 3) robenidine 33 parts per million (ppm); 4) decoquinate 30 ppm; 5) clopidal 125 ppm; 6) zoalene 125 ppm; 7) diclazuril 1 ppm; 8) amprolium 125 ppm; 9) salinomycin 66 ppm; 10) narasin 39.6 ppm + nicarbazin 39.6 ppm; and 11) narasin 74.25 ppm. IM5 used the same IM3 treatments 1-11 plus 12) nicarbazin. IMT: 1) NMNC; 2) NMC; 3) lasalocid 79.2 ppm; 4) monensin 66 ppm; 5) amprolium 125 ppm; 6) zoalene 125 ppm; and 7) nicarbazin 125 ppm. The challenge for each vaccine was 100 times the commercial recommended dose given orally on D2 (14 days of age). For trials IM3 and IM5, on D8 (6 days postchallenge) all chickens were coccidia lesion scored. IMT oocysts per gram (D7-9) and dropping scores (D8) were determined instead of lesion scores. For IM3 and IM5 vaccines, the results showed that all strains were sensitive to all anticoccidial drugs. For turkey IMT vaccine, the results showed that all strains were highly sensitive to all anticoccidial drugs. This information can serve as a foundation for the use of these coccidia vaccines in the restoration of coccidia sensitivity in the field.

Polyphenols and Organic Acids as Alternatives to Antimicrobials in Poultry Rearing: A Review

For decades antibiotics have been used in poultry rearing to support high levels of production. Nevertheless, several problems have arisen because of the misuse of antibiotics (i.e., antibiotic resistance, residues in animal products, environmental pollution). Thus, the European Union (EU) as well as the European Food Safety Authority (EFSA) promote action plans to diminish the use of antibiotics in animal production. Alternatives to antibiotics have been studied. Polyphenols (PPs) or organic acids (OAs) seem to be two accredited solutions. Phenolic compounds, such as phenols, flavonoids, and tannins exert their antimicrobial effect with specific mechanisms. In contrast, short chain fatty acids (SCFAs) and medium chain fatty acids (MCFAs), the OAs mainly used as antibiotics alternative, act on the pathogens depending on the pKa value. This review aims to collect the literature reporting the effects of these substances applied as antimicrobial molecules or growth promoter in poultry feeding (both for broilers and laying hens). Organic acids and PPs can be used individually or in blends, exploiting the properties of each component. Collected data highlighted that further research needs to focus on OAs in laying hens' feeding and also determine the right combination in blends with PPs.

Effects of coadministration of corn oil and ponazuril on serum and cerebrospinal fluid concentrations of ponazuril in horses

Background

Ponazuril is used for the treatment of equine protozoal myeloencephalitis (EPM). Coadministration of ponazuril with oil could result in higher serum and cerebrospinal fluid (CSF) concentrations of ponazuril.

Hypothesis

Coadministration of corn oil will result in higher serum and CSF concentrations of ponazuril than when ponazuril is administered alone.

Animals

Ten resident university‐owned adult horses of either sex and >2 years of age.

Methods

Cohort study. Ponazuril oral paste (5 mg/kg BW; ponazuril treatment group (PON); n = 5), or ponazuril oral paste (5 mg/kg BW; ponazuril and oil treatment group (PONOIL; n = 5) coadministered with 2 oz of corn oil q24h for 21 days. Horses were treated once daily, for 21 days. Blood was collected on days 0, 7, 14, and 21 before dosing. In addition, CSF was collected on days 1, 7, 14, and 21. The concentration of ponazuril was determined in serum and CSF and results compared using repeated measures ANOVA.

Results

Coadministration of ponazuril with 2 oz of corn oil resulted in higher concentrations of ponazuril in serum (at steady state) than that found in horses given ponazuril alone (6.2 ± 0.9 mg/L versus 4.5 ± 1.0 mg/L; P = .004) (mean ± 1 SD). Cerebrospinal fluid concentrations of ponazuril were also greater in horses that received ponazuril and oil (0.213 mg/L ± 0.04 versus 0.162 ± 0.04 mg/L) (P = .03).

Conclusions and Clinical Importance

Results suggest that coadministration of corn oil with ponazuril might enhance the effectiveness of treatment with ponazuril.