Oocyst Excretion Research Articles

Effect of ethanol extract from Enterolobium cyclocarpum fruit on Leghorn chickens exposed to Eimeria.

There are concerns about residues of drugs in meat that are used to prevent coccidiosis in chickens. Natural compounds are an alternative to drugs. Two studies investigated the effect of an extract of Enterolobium cyclocarpum fruits (EEC) in the feed of male Leghorn chickens exposed to Eimeria spp. In the first experiment, the administration of EEC after infection with Eimeria spp. was investigated over 16 days. One thousand chickens were randomly housed in 20 pens of 1 m2 each. The pens were randomly assigned to each treatment. Five treatments were administered, containing 150, 300 and 450mg/kg of EEC in the feed, the fourth treatment (C) contained 0.5g/kg of a commercial anticoccidial, and the fifth treatment provided no treatment (WA). The second experiment lasted 18 days. Administration of the EEC began five days before the chickens were infected with Eimeria spp. Four hundred and eighty chickens were randomly allocated to 24 pens of 1 m2. The pens were randomly assigned to each treatment. In the second experiment, the same five treatments were tested and one additional treatment containing 300mg EEC plus 1g of polyethylene glycol (PEG)/kg of feed (E300PEG). In the experiment one chickens in the EEC treatments had lower faecal oocyst excretion (OE) on day 14 post infection with Eimeria spp., than chickens in the WA treatment (P < 0.05). A reduction in live weight gain (LWG) was observed in the EEC treatments (P < 0.05). In the second experiment, the excretion of oocysts in chickens from the EEC and E300PEG treatments on day 13 post-infection with Eimeria spp. was the same as in the C treatment and lower than in the WA treatment (P < 0.05). LWG was lower in the EEC treatments than in the C treatment (P < 0.05). However, the Chickens in the E300PEG and C treatments had similar LWG (P > 0.05) suggesting that PEG inhibits the negative effect of EEC tannins on LWG. In conclusion, the addition of EEC to chicken feed reduced both OE and LWG. Treatment with EEC and PEG (E300PEG) reduced the excretion of oocysts without negative effects on LWG.

The effects of infectious dosages on endogenous phage and the excretion of Eimeria tenella oocysts of infected chicken

This study was conducted to evaluate the effects of four dosages of oocyst inoculation (1×102, 1×103, 1×104, and 1×105 oocysts/chick) on oocyst patterns in feces, lesion score, and the endogenous phase of Eimeria tenella in the tissue of infected chickens. Oocysts in feces were collected daily from 4 to 10 day-post-infection (dpi). Chickens were killed at 0, 3, 5, and 10 dpi to evaluate the lesion score and the endogenous phage in the tissue by hematoxylin and eosin staining. The results showed that chickens in the highest dosage group discharged oocysts the earliest (5 dpi), while oocysts were detected in the other 3 groups 1 day later (6 dpi). The results of the histopathological examination showed that the time to detect the development stages of E. tenella in the tissue was similar among the experimental groups. Specifically, the asexual stages (1st and 2nd schizonts) were detected at 3 dpi, and immature oocysts were found in the cecum tissue at 5 dpi in all experimental groups. Overall, the results indicated that the oocyst dosages do not affect the replication of E. tenella in intestinal epithelial cells but may influence the excretion of oocysts from the intestinal tissue.

Aflatoxin B1 as a complicit in intestinal damage caused by Eimeria ovinoidalis in lambs: Novel insights to reveal parasite-gut battle

Mycotoxins, unavoidable contaminants in feed and feed ingredients, have the potential to influence the incidence and severity of various diseases upon ingestion. Sheep coccidiosis is an enteric disease caused by protozoa of Eimeria spp. However, the extent to which the presence of aflatoxin b1 (AFB1) synergistically exacerbates damage to intestinal health in lambs with Eimeria remains unclear. 50-day-old female lambs were randomly assigned to a 2 × 2 factorial arrangement of treatments for 15 days to assess the impact of AFB1 exposure on lambs with or without Eimeria (E.) ovinoidalis infection. Our findings reveal that AFB1 synergistically intensifies damage to intestinal health in lambs challenged by E. ovinoidalis. This is evidenced by disruptions to the intestinal microbiota and reductions in the production of short-chain fatty acids. AFB1 further aggravates damage to the cecal mechanical barrier. Additionally, AFB1 contributes to the entry of lipopolysaccharide into the bloodstream, activating the inflammatory response. Interestingly, AFB1 exposure history results in an early peak of oocyst excretion and a decreased number of oocyst excretion in E. ovinoidalis infected lambs. This may be closely linked to the destruction of the intestinal epithelial cell structure and its apoptosis, as indicated by a decreased ratio of Bcl-2 to Bax and increased caspase-3 levels. Mechanistically, proteomics analysis identified mitochondrial dysfunction (inhibition of the oxidative phosphorylation pathway) as the primary factor intensifying intestinal epithelial cell destruction caused by coccidia, exacerbated by AFB1 through the inhibiting the conversion of NADH to NAD+ in the cecum of lambs via down-regulation of the PGC-1α/NRF1/TFAM pathway. Overall, these results offer novel insights into the AFB1 complicity in accelerating intestinal damage caused by E. ovinoidalis in lambs. Targeting the mitochondrial oxidative phosphorylation pathway of the intestine may represent a new therapeutic strategy against the detrimental effects of mycotoxin and coccidia.

EFFECTIVENESS OF TREATMENT OF SPONTANEOUS MIXED COURSE OF ISOSPOROSIS AND CRYPTOSPORIDIOSIS IN PIGLETS

Intestinal coccidiosis, in particular isosporosis and cryptosporidiosis, lead to significant economic losses in the global pig industry. Piglets become infected immediately after birth through ingestion of sporulating oocysts from previously infected litter, as sows are considered a secondary source of infection for them. Proper housing and hygiene, which reduce the accumulation of oocysts in the environment and exposure of piglets to sporulation oocysts, are key to disease prevention. The goal of the work. To determine the effectiveness of eimeriostatics for the mixed course of isosporosis and cryptosporidiosis in piglets. The effectiveness of the drugs was determined on 14-day-old piglets of the breed ''Velika Bila''. The piglets of the first experimental group were given the drug Turil 5%, the second experimental group - Brovitacoccid, the third experimental group - Amprolev-plus." The dynamics of the infestation of piglets with isospores and cryptosporidia after the use of the drugs and their effectiveness were determined on the 7th, 14th and 28th days by counting the number of oocysts in 10 fields of view of the microscope according to the method of N.P. Orlova (1956). After treatment of piglets with the drug Turil 5% on the 14th day, the release of I. suis decreased to 3.9 ± 0.1 oocysts, and on the 28th day they were not recorded, while on the 28st day C. suis was at the level 7.4±0.2 oocysts in 10 fields of view of the microscope. When using Brovitacoccide on the 14th and 28th days, I. suis was not recorded, and the infestation of piglets by C. suis was 3.5±0.2 oocysts. The best indicators regarding the reduction of oocyst excretion were obtained in the group of piglets treated with the drug Amprolev-plus. On the 14th day, only the release of I. suis oocysts was recorded (5.1±0.1 oocysts in 10 fields of view of the microscope), and on the 28th day, the release of C. suis and I. suis oocysts was not recorded. On the 14th day, the effectiveness of Brovitacoccsid against I. suis and Amprolev-plus against C. suis was 100%, and already on the 28th day, 100% effectiveness of Amprolev-plus also showed against I. suis.

Effect of dietary treatments on performance, oocysts shedding and lesion scores in broiler chickens experimentally challenged with Eimeria infection

Although anticoccidials effectively control coccidiosis, a needed reduction in the reliance on antimicrobials in animal production leads to the exploration of alternative compounds. The present study aimed to test five different dietary treatments to counteract the negative impact of coccidiosis on broiler chickens’ health and performance. 1-day-old male Ross 308 broilers (n = 960) were randomly assigned to one of eight treatments, with six cages per treatment (20 birds/cage). To the diet of the broiler chickens of treatments (Trt) 1–5, a synbiotic was added from d0-10. From d10–28, birds of Trt1 and Trt2 were fed synbiotics, whereas birds of Trt3 were fed diets with glutamine, and birds of Trt4 and Trt5 were fed diets with a combination of β-glucans and betaine. From d28-35 onwards, birds of Trt1 were fed a diet with a synbiotic, whereas birds of Trt2-4 received diets with glutamine, and birds of Trt5 were fed a non-supplemented diet. Birds of the positive control group (PC; Trt6) were fed a standard diet supplemented with an anticoccidial (Decoquinate). The challenged negative control (NCchall; Trt7) and non-challenged negative control (NC) Trt8 were fed a standard diet without anticoccidial or other dietary treatment. At 7 days (d) of age, all birds were inoculated with 1 023, 115, and 512 sporulated oocysts of E. acervulina, E. maxima, and E. tenella, respectively, except for Trt8. Body weight gain (BWG), feed intake, and feed conversion ratio were assessed for each feeding phase (d0-10, d10-28 and d28-35) and overall experimental period (d0-35). Oocyst shedding, Eimeria lesion scores, cecal length, and relative weight were assessed at d13, d22, d28 and d35. Additionally, oocyst shedding was determined at d9 and d17. Litter quality was evaluated at d27 and d34, and footpad lesions at d34. During the starter (d0-10) and finisher (d28-35) periods, performance did not differ between the treatments. During the grower period (d10-28), Trt6 (PC) and Trt8 (NC) chickens had the highest BWG of all treatments (P < 0.001). Dietary treatment had no effect on litter quality and severity of footpad lesions. In the PC group (Trt6), low oocyst excretion and lesion scores were found. When comparing Trt1-5 with NCchall (Trt7), none of the treatments significantly reduced oocyst output or lesion scores. In conclusion, in this experiment, none of the dietary treatments performed similar or better compared to the PC group (Trt6) regarding performance or reducing Eimeria oocyst shedding or lesion scores.

Supplementing low protein diets with methionine or threonine during mixed Eimeria challenge

We investigated the effects of supplementing low protein diets with methionine (Met) or threonine (Thr) during a mixed Eimeria (consisting of E. acervulina, E. maxima and E. tenella) challenge in broilers. All birds were fed the same starter diet (d1-9) and finisher diet (d28-35) which met Cobb 500 nutrient specifications. Birds were allocated to 1 of 4 dietary treatments from d9 to 28: a standard protein diet (19% CP); a low protein diet (16% CP); or the low protein diet supplemented with Met or Thr at 50% above recommendations. On d14, half of the birds were challenged, and half of the birds were unchallenged. From d14 to 28, feed intake was recorded daily and BW every 3 or 4 d. Oocyst excretion was measured daily from d18 to 27. On d21 and 28, 3 birds per pen were euthanized to assess nutrient digestibility, cytokine expression and intestinal histology. During the acute stage of the challenge, challenged birds reduced ADFI and ADG (P < 0.05). In the pre-patent and recovery stages, birds given the 16% CP diets increased ADFI (P < 0.05), meanwhile there were no differences in ADG in these stages (P > 0.05). Nutrient digestibility was reduced in challenged birds in the acute stage (P < 0.05) but tended to be greater than in unchallenged birds during the recovery stage. There was no significant effect of diet on oocyst excretion or intestinal histology (P > 0.05). Interactions were observed between diet and challenge on IL-10 and IL-21 expression in the cecal tonsils during the acute stage of the challenge (P < 0.05), due to reduced IL-10 expression in challenged Thr birds and greater IL-21 expression in challenged Met birds. Supplementation with Thr or Met had limited effects on the outcomes of a mixed Eimeria challenge but provides benefits to the host by enhancing their immune response.

The effect of an injectable toltrazuril – gleptoferron (Forceris®) on Cystoisospora suis oocyst excretion and growth of neonatal piglets pre- and post-weaning

In this study the efficacy of an intramuscular formulation of toltrazuril combined with gleptoferron for the control of porcine cystoisosporosis caused by Cystoisospora suis was investigated. The study was carried out on three Belgian farms with a confirmed history of C. suis infections. As none of the farms implemented a standardized toltrazuril treatment regimen for their piglets, the presence of resistant C. suis strains seems improbable. In total 90 litters, representing 1249 piglets, were included in the study and randomly allocated to either the treatment or control group. Piglets in the treatment group received a single intramuscular injection, containing 45 mg toltrazuril and 200 mg gleptoferron, between 1 and 3 days of age. Piglets in the control group received a single injection with only 200 mg gleptoferron. The effect of treatment on oocyst excretion, expressed in oocysts per gram of feces (OPG), average daily weight gain (ADG) and mortality was determined both pre- and post-weaning. A significant decrease in OPG as well as a decrease in the number of litters (pre-weaning) and pens (post-weaning) that tested positive for cystoisosporosis, was observed in the treated animals compared to the controls. Furthermore, treatment resulted in an increased ADG during the period from day 1 to day 21 (p-value: 0.03881). There was no significant difference in mortality observed between the treatment group to the control group (p-value: 0.2167). To our knowledge, this is the first report on the effect of toltrazuril on oocyst excretion after weaning. This finding highlights the potential long-term benefits of the treatment beyond the initial administration.

In silico and in vivo evaluation of the anti-cryptosporidial activity of eugenol.

Cryptosporidiosis is an opportunistic parasitic disease widely distributed worldwide. Although Cryptosporidium sp. causes asymptomatic infection in healthy people, it may lead to severe illness in immunocompromised individuals. Limited effective therapeutic alternatives are available against cryptosporidiosis in this category of patients. So, there is an urgent need for therapeutic alternatives for cryptosporidiosis. Recently, the potential uses of Eugenol (EUG) have been considered a promising novel treatment for bacterial and parasitic infections. Consequently, it is suggested to investigate the effect of EUG as an option for the treatment of cryptosporidiosis. The in silico bioinformatics analysis was used to predict and determine the binding affinities and intermolecular interactions of EUG and Nitazoxanide (NTZ) toward several Cryptosporidium parvum (C. parvum) lowa II target proteins. For animal study, five groups of immunosuppressed Swiss albino mice (10 mice each) were used. Group I was left uninfected (control), and four groups were infected with 1,000 oocysts of Cryptosporidium sp. The first infected group was left untreated. The remaining three infected groups received NTZ, EUG, and EUG + NTZ, respectively, on the 6th day post-infection (dpi). All mice were sacrificed 30 dpi. The efficacy of the used formulas was assessed by counting the number of C. parvum oocysts excreted in stool of infected mice, histopathological examination of the ileum and liver tissues and determination of the expression of iNOS in the ileum of mice in different animal groups. treatment with EUG resulted in a significant reduction in the number of oocysts secreted in stool when compared to infected untreated mice. In addition, oocyst excretion was significantly reduced in mice received a combination therapy of EUG and NTZ when compared with those received NTZ alone. EUG succeeded in reverting the histopathological alterations induced by Cryptosporidium infection either alone or in combination with NTZ. Moreover, mice received EUG showed marked reduction of the expression of iNOS in ileal tissues. Based on the results, the present study signified a basis for utilizing EUG as an affordable, safe, and alternative therapy combined with NTZ in the management of cryptosporidiosis.

Prophylactic and Therapeutic Efficacy of Ultrasonicated Rosmarinus officinalis Ethanolic Extract and its Chitosan-Loaded Nanoparticles Against Eimeria tenella Infected Broiler Chickens

PurposeThe in vivo efficacy of ultrasonicated Rosmarinus officinalis ethanolic extract (UROEE) and its chitosan-loaded nanoparticles (UROEE-CsNPs) was investigated as a dietary prophylactic agent and as a therapeutic treatment against Eimeria tenella infected broiler chickens.MethodsChickens were infected with 4 × 104E. tenella oocysts at 21 days old for primary infection and with 8 × 104 oocysts at 35 days old for secondary infection. Eleven experimental groups were conducted. Dietary addition of 100 mg/kg UROEE and 20 mg/kg for CsNPs as well as UROEE-CsNPs were included for prophylactic groups from day 1 to 42. The same doses were used for therapeutic treatment groups for 5 constitutive days. Oocyst output in feces was counted. Histopathological and immunohistochemical studies were conducted. Gene expression of pro-inflammatory cytokines as IFN-γ, IL-1β and IL-6 as well as anti-inflammatory cytokines as IL-10 and TGF-β4 was analyzed using semi-quantitative reverse transcriptase-PCR.ResultsThe results showed an efficacy of UROEE, CsNPs and UROEE-CsNPs in reduction of oocyst excretion and improving the cecal tissue architecture. CD4+ and CD8+ T lymphocytes protein expression were reduced. E. tenella infection lead to upregulation of pro-inflammatory cytokines as IFN-γ, IL-1β, IL-6 and anti-inflammatory cytokines as TGF-β4 following primary infection, while their expression was downregulated following secondary infection.ConclusionThe dietary prophylactic additives and therapeutic treatments with UROEE, CsNPs and UROEE-CsNPs could decrease the inflammatory response to E. tenella as indicated by oocyst output reduction, histopathological improvements, CD4+ and CD8+ T cells protein expression reduction as well as reducing mRNA expression levels of the tested cytokines following primary and secondary infections. Consequently, these results will help to develop better-combating strategies for the control and prevention of coccidiosis on poultry farms as a dietary prophylactic agent or as a therapeutic treatment.Graphical

Biological characteristics of a precocious line of Eimeria tenella.

The Eimeria tenella Yulin strain (EtYL), which is sensitive to most anti-coccidial drugs, was isolated in the Yulin area of Guangxi, China. Then, Eimeria tenella Yulin precocious line (pEtYL), a precocious line with a prepatent period of 108h, was obtained through early selection. The biological characteristics of pEtYL, including its morphology, purity, oocyst excretion curve, reproductive capacity, pathogenicity, immunogenicity, and preservation time, were comprehensively analyzed. The results showed that the isolated precocious line of E. tenella exhibited high purity, relatively weak pathogenicity, and good immunogenicity and can be used as a live vaccine line for chicken coccidiosis.

Dynamics of excretion of Eimeria spp oocysts in alpacas (Vicugna pacos) during peripartum

Infections of alpacas at very early ages suggest that the dams may act as asymptomatic carriers of some Eimeria species. The aim of this study was to determine the dynamics of Eimeria spp oocyst excretion in alpaca dams during the calving season at the "La Raya" Research and Production Centre, Puno, Peru. Faecal samples were taken from 50 clinically healthy alpacas of the Huacaya breed naturally infected with Eimeria spp in the two weeks prepartum, week of delivery and four weeks postpartum (period December 2018 - March 2019). Dams were categorized into three age groups [A: 3-4 (n=19), B: 5-8 (n=26) and C: 9-12 years (n=5)]. Sample analysis was carried out using Sheather solution flotation and McMaster techniques. The pregnant dams entered the calving season excreting E. punoensis [49/50 (98%)], E. alpacae [43/50 (86%)], E. lamae [5/50 (10%), and E. macusaniensis [3/50 (6%)] but not E. ivitaensis. The percentage of dams shedding oocysts of E. alpacae and E. punoensis increased after the second week postpartum, while it was found a minimal excretion load of E. macusaniensis and E. lamae before and after the calving season. There was a significant difference in opg between A and B, and between the two weeks prepartum and four weeks postpartum, in addition to a very low negative correlation (-0.0538) between the number of opg and age (p=0.0468). Animals infected with E. punoensis presented 6.5 times the prevalence of those parasitized with E. alpacae (p&lt;0.001; 95% CI 2.33-18.13).

Comparing the effect of phytobiotic, coccidiostat, toltrazuril, and vaccine on the prevention and treatment of coccidiosis in broilers

This study compared 2 herbal anticoccidiosis drugs (water-soluble and feed-additive drugs) with monensin coccidiostat, toltrazuril (TTZ, anticoccidiosis drug), and Livacox Q (anticoccidiosis vaccine) in terms of their effects on the prevention and treatment of coccidiosis in broilers. In this study, 280 Ross 308 broiler chickens (a mix of both genders) were used in a completely randomized design with 7 treatments and 5 replications each including 8 chickens per replicate. On d 21 of rearing, all experimental groups, except for the negative control group (NC), were challenged with a mixed suspension of common strains of Eimeria, and the intended indices were assessed, including performance indices, number of oocysts per gram (OPG) of feces, intestinal injuries, and the total number of intestinal bacteria. In addition, the NC and the group receiving the monensin had greater body weight gain (BWG) (P < 0.05). At the end of week 6, the monensin group had the highest feed intake (FI), while the water soluble medicine treatment resulted in the lowest feed intake (P < 0.05). Regarding the lesion scores on day 28, the highest and lowest rates of jejunal injuries were observed in the positive control group (PC), the monensin and vaccine group respectively. The rate of oocysts excretion (oocysts per gram of feces = OPG) on different days was higher in the PC group, and the use of monensin could further reduce excretion compared to the other groups (P > 0.05). Based on a comparison of the population of lactic acid bacteria between the NC and both medicinal plant treated groups, the use of these products could increase the population of these types of bacteria. Moreover, the population of Escherichia coli was less considerable in the NC and herbal powder groups (P < 0.05). Overall, similar to commercial medicines, the herbal medicines used in this project can be effective in the prevention and treatment of coccidiosis and can improve profitability in broiler rearing centers by improving intestinal health.

A Field Study Evaluating the Effects of Diclazuril and Oregano Oil for the Prevention of Coccidiosis in Fattening Rabbits

A Field Study Evaluating the Effects of Diclazuril and Oregano Oil for the Prevention of Coccidiosis in Fattening Rabbits

Metaphylactic strategies using toltrazuril against coccidiosis in goat kids

Goat coccidiosis compromises animal welfare, reduces productivity and may cause mortality and delayed growth rates in goat kids around the weaning period worldwide. This field study was conducted to evaluate the efficacy of metaphylactic treatments with two doses of toltrazuril (20 or 40 mg/kg body weight – BW, p. o.), at different timing, in kids naturally infected with Eimeria spp. A total of 97 healthy goat kids (Majorera milk aptitude breed) were divided into five groups, depending on the age of treatment (2 or 7 weeks). One group remained untreated as a negative control until the end of the study. Faecal oocyst shedding, faecal consistency, and body weight of the animals were monitored at day 0 and at weekly intervals. Counts of oocysts per gram of faeces (OPG) were determined by a modified McMaster technique. Morphometric identification of Eimeria species was carried out on individual faecal samples from each experimental group after oocyst sporulation. Goat kids treated at two weeks of age maintained OPG values close to zero during the 5 weeks post-treatment and, overall, had lower faecal oocyst counts than untreated control animals. No significant differences were observed between the two doses of toltrazuril used in two-week-old treated animals. By contrast, when treatment was carried out at seven weeks of age, the dose of 40 mg/kg BW of toltrazuril reduced oocyst levels for longer and to a greater extent than the 20 mg/kg dose. Irrespectively of the treatment and dose, toltrazuril delayed the appearance of pathogenic Eimeria species, i. e. Eimeria ninakohlyakimovae and Eimeria arloingi. As a whole, Eimeria christenseni, with a rather moderate pathogenicity, was highly predominant throughout the study period, including the untreated control group, which was probably the reason why clinical signs of coccidiosis were barely observed throughout the experiment. Under these circumstances, the positive effect of toltrazuril on body weight condition observed in some treated groups was difficult to correlate to the timing and doses. Metaphylactic treatments with 20 mg/kg BW toltrazuril given at two weeks of age are sufficient to control oocyst excretion in goat kids; whereas if administered later in 7-week-old animals, thereby coinciding with the frequently observed peak of oocyst elimination in goat kids under field conditions, a higher dose might be advisable to prevent environmental contamination with infectious oocysts.

The Immunoprotective Effect of ROP27 Protein of Eimeria tenella.

Eimeria tenella rhoptry protein has the properties of a protective antigen. EtROP27 is a pathogenic gene that is detected via a transcriptome, but its expression pattern, immunogenicity, and potency are unknown. Therefore, a gene segment of EtROP27 was amplified and transplanted into the pET28a prokaryotic vector for the expression of the recombinant protein, and it subsequently purified for the generation of a polyclonal antibody. Then, RT-PCR and Western blotting were performed to understand the expression pattern of EtROP27. Subsequently, animal experiments were conducted to evaluate the immunoprotective effect of the recombinant protein with different immunizing doses (50, 100, and 150 μg). The results showed that the expression of EtROP27 gradually increased with the prolongation of infection time, reaching the highest level at 96 h and then decreasing. Additionally, EtROP27 is a natural antigen of coccidia that can stimulate the body to produce high levels of IgY. As with recombinant protein vaccines, the results of immune protection evaluation tests showed that the average weight gain rates of the immune challenge groups were significantly higher than that of the challenged control group, and their average lesion scores were significantly lower than that of the challenged control group. Furthermore, the oocyst excretion decreased by 81.25%, 86.21%, and 80.01%, and the anticoccidial index was 159.45, 171.47, and 166.75, respectively, for these groups. EtROP27 is a promising antigen gene candidate for the development of a coccidiosis vaccine.

Impacts of Eimeria coinfection on growth performance, intestinal health and immune responses of broiler chickens

Coccidiosis caused by Eimeria is one of the most severe chicken diseases and imposes huge economic losses to the poultry industry globally. Multi-Eimeria species coinfections are common with the most prevalent combination being mixtures of Eimeria acervulina and Eimeria tenella. Although detrimental impacts of either E. acervulina or E. tenella on chicken health are well recognized, no information is available regarding their coinfection effects so far. This study was designed to investigate the influence of coinfection with E. acervulina and E. tenella on broiler chickens. 144 one-day-old broiler chickens within each of trials (trial I or II) were divided into four groups, namely, control group (CG), E. acervulina infection group (EAIG), E. tenella infection group (ETIG) and dual (E. acervulina and E. tenella) infection group (DIG). Then, chickens were measured for weight loss, lesion scores, oocyst outputs, histological changes and expressions of pro-inflammatory (interleukin [IL]−6, IL-8 and IL-18), regulatory (IL-10 and IL-22) cytokines and Toll-like receptors (TLR; TLR2 and TLR4) as well as intestinal barrier (mucin 2 [MUC2] and fattey acid-bingding proteins 2 and 6 [FABP2 and FABP6])- and tight junction (TJ; zonula occluden-1 [ZO-1], occludin [OCLN], and claudins 1 and 5 [CLDN1 and CLDN5])-related proteins at 3, 5, 7, 10, 14 and 21 days post-infection, respectively. Our results consistently showed that although ETIG and DIG exhibited a higher level of weight loss and a more amount of oocyst excretion than EAIG, DIG had lighter lesions than EAIG in the early phase because of coinfection with E. tenella. A higher (P < 0.05) ratio of duodenal villous height to crypt depth was also observed in DIG than EAIG. Moreover, histological changes in the duodenum and cecum varied by single and dual Eimeria infections. Expressions of the intestinal barrier- and TJ-related genes of EAIG, ETIG and DIG were significantly (P < 0.05) upregulated but their levels exhibited differential changes among infected chickens. Similarly, the infected chickens showed significant (P < 0.05) inflammatory responses and higher (P < 0.05) expressions of TLRs in the intestines in comparison to CG. These results presented a comprehensive physiological, pathological and immunological characterization of E. acervulina and E. tenella coinfection in broiler chickens and also shed insights into pathogenesis of multi-coccidia coinfections.

Impact of carob (Ceratonia siliqua L.) pulp inclusion and warm season on gastrointestinal morphological parameters, immune-redox defences and coccidiosis in concentrate-fed light lambs

This study aimed to evaluate the effects of dietary carob (Ceratonia siliqua L.) pulp and warm season on gastrointestinal morphological parameters, immune-redox defences and coccidiosis in concentrate-fed light lambs. Weaned lambs were assigned to one of three concentrate-based diets: C0 (without carob pulp), C15 (150 g/kg of carob pulp) and C30 (300 g/kg of carob pulp) from 40 to 80 days of age in two consecutive cold and warm batches. Blood samples were collected at Day 80 to determine the metabolic status. Rectal faeces were sampled at Days 50, 65 and 80 to determine consistency and oocyst count per gram. Inclusion of carob pulp in lamb diets did not affect lamb growth but reduced coccidia oocyst excretion, improved faecal consistency and gastrointestinal morphological parameters, enhancing the ruminal thickness of the papilla living strata and reducing the darkness of the epithelium colour. Moreover, carob condensed tannins in the lambs' diet enhanced the expression of antioxidant SOD2 in rumen, while down-regulated NRF2, SOD1, CAT and PPARG in ileum. There was no interaction between the treatments and season in the evaluated variables. Lambs from the warm season exhibited reduced growth performance, altered ruminal epithelium, lower circulating iron levels, increased protein concentrations and higher coccidiosis susceptibility. In addition, regulatory immune and antioxidant mechanisms to counterbalance reactive oxygen species production in gastrointestinal tissues were evident. Dietary inclusion of carob pulp (150 and 300 g/kg) in lamb diets improved gastrointestinal health and homeostasis but did not ameliorate the deleterious effects of warm season.

Melatonin Administration to Pregnant Ewes for Coccidiosis Control in Their Offspring.

In livestock research, there has been a growing interest in the impact of melatonin on both health and disease conditions. The hypothesis of the present study was that melatonin treatment prenatally could support the immune competence and growth of experimentally infected lambs. This is the first study that aimed to investigate the impact of melatonin administration throughout pregnancy on immunity and oocyst excretion of pre-partum ewes and their offspring after experimental infection with Eimeria species. Thirty pregnant ewes were allocated into five equal groups, ΚΜ, ΚC, CM, CC, and NC, and gave birth to 47 lambs. Ewes of the KM and KC groups were orally challenged with a cocktail of Eimeria-sporulated oocysts (mainly consisting of Eimeria ovinoidalis), on day 120 of pregnancy, as well as all the lambs at the age of 5-9 days apart from those born from the NC group (environmental control). Fecal samples were collected from all ewes before infection and at parturition and from all lambs 14 times (S0-S13), before infection and during the following 8 weeks, for counting oocysts per gram of feces (OPG). Immunoglobulin (IgG) and cytokine (IL-1β, IL-6, IL-10, IFN-γ) levels were determined in ewes' plasma collected before infection and at parturition, in lambs' plasma at 24 and 72 h after their birth, and in colostrum samples at parturition and 72 h later. Body weight of lambs was recorded five times from birth until the age of 60 days. Accordingly, the leucogram was evaluated in blood samples collected six times within the same period. On average, IgG concentration was higher (p < 0.05) in the blood of KM-ewes compared to KC and CC groups and in colostrum of KM-ewes compared to other groups (p < 0.001). KM-lambs had greater IgG titer and IFN-γ level than the other groups (p < 0.05). The IL-10/ IFN-γ ratio in KM-ewes was lower than the CC group (p = 0.06). Overall, the growth rate of lambs did not differ among groups (p > 0.05). Total oocysts' excretion in KM- and CM-lambs was reduced by 94.9% (p = 0.05) and 92.6% (p = 0.025), respectively, compared to KC-lambs, following the 3-week period after challenge, when E. ovinoidalis predominated in all groups. The dominant type of leucocytes was monocytes in all experimentally infected lambs, but not in NC-lambs, while overall lymphocytes were lower in KC-lambs than in NC-lambs (p < 0.05). Considering that almost all young indoor-reared lambs are exposed to coccidia species during their early life, melatonin treatment prenatally could suggest an alternative management tool in alleviating infection pressure.

Production performance and economic analysis of broiler chickens after vaccination with a live attenuated vaccine against avian coccidiosis.

The objective of this study was to evaluate the effectiveness of live attenuated commercial vaccine LIVACOX® T against avian coccidiosis upon parasite exposure through its correlation with productive and economic performance, clinical observation, and oocyst excretion of broiler chickens. For this purpose, 420 1-day-old Cobb chicks were divided into five groups of 84 birds: (G1) unvaccinated and unchallenged control; (G2) vaccinated on day 0; (G3) challenged on day 1; (G4) vaccinated on day 0 and challenged on day 14; and (G5) challenged on day 14. For 28days, the clinical signs of infection, weight and feed conversion of the birds, and excretion of oocysts in the feces were evaluated. Macroscopic analysis of intestinal lesions in birds was also performed. After vaccination in G2, G3, and G4 as well as after challenge in G3, G4, and G5, there was an increase in oocyst excretion. In the analysis of weight gain, the difference in final weight between groups G3 and G4 is - 105.74g per bird. Therefore, if we multiply this value by the average number of birds slaughtered per day in a medium/large slaughterhouse (250,000), we have 26,435kg of chicken meat per day of slaughter, representing 581,570kg of monthly losses (22days of slaughter/month), or approximately R$3,489,420.00 (US$872,355.00), considering the commercial value at R$6.00/kg (US$ 1.5/kg). Thus, the productive and economic impact of coccidiosis in broiler chickens is evident, and the importance of vaccination to prevent the occurrence of the disease and reduce subsequent loss is highlighted.

In vivo anticoccidial activity and immune response of Moringa oleifera and Vernonia amygdalina leaves against Eimeria magna and Eimeria media in rabbits.

The aims of this study were to determine the immune response and the anticoccidial activity induced by Moringa oleifera and Vernonia amygdalina leaves in rabbits infected with Eimeria magna and Eimeria media. Thirty-five-day-old rabbits, free from coccidia, were infested with 2.103 oocysts of Eimeria magna and Eimeria media, then received the acetone extract of the leaves of Moringa oleifera and Vernonia amygdalina at different doses by oral gavage. The inhibition of the excretion of oocysts was evaluated by the McMaster technique and the levels of cytokines (IL-4 and IL-12) and immunoglobulin IgG were assayed by the ELISA method. The in vivo efficacy on E. magna and E. media oocysts was 95.43% and 96.53% for Moringa oleifera and Vernonia amygdalina at 1000 mg/kg bw against 98% for the positive control. Interestingly the plant extracts increased the production of interleukin (IL) and immunoglobulins (Ig) compared to controls. Plasma IL-4 levels (pg/ml) in rabbits were 128.94 and 131.38; those of IL-12 (pg/ml) were 395.55 and 426.56, and then for those of IgG (μg/ml) were 14.70 and 13.94 respectively with the acetone extracts of Moringa oleifera and Vernonia amygdalina on D14 PT at 1000 mg/kg bw. This study indicates that Moringa oleifera and Vernonia amygdalina can be used as an alternative to synthetic anticoccidials. These plants could be used to increase the resistance of the immune system of rabbits to infestations of Eimeria species in rabbit farms.