Oocyst Counts Research Articles

Efficacy and safety of diclazuril nanoemulsion in control of Eimeria tenella in broilers

BackgroundNanotechnology has the potential to reduce drug dosage while increasing efficacy; thus, the current work intends to synthesize diclazuril nanoemulsion and assess its performance against experimental coccidiosis in broilers.MethodsDiclazuril nanoemulsion (DZN) was formulated and characterized by zeta seizer and zeta potential. The formulated DZN was evaluated in vivo against Eimeria tenella infected chicks. DZN and DZ were used in 2 programs; therapeutic and prophylactic. A total of 210 one-day-old broiler chicks were distributed equally into six groups. The controls were negative uninfected untreated and positive infected untreated (G1 & G2). Therapeutic groups (G3 & G4) treated by DZ and DZN after appearance of the clinical signs of coccidiosis and continued for 5 days. Prophylaxis groups (G5 & G6) received DZ and DZN at 3 days before challenge and continued for 5 days after infection. The treatments dosages were 10 mg/mL for DZ of commercial origin and 2.5 mg/mL for the prepared DZN. All groups (except negative control) orally infected then followed up for clinical signs of coccidiosis, mortality rate, oocysts count, performance, hematological and biochemical parameters in addition to histopathological lesions.ResultsThe therapeutic groups showed that both treated groups (DZ and DZN) revealed similar results including good body weight gain, a low lesion caecal score, a low daily and total oocyst shedding count, and a low mortality rate. Regarding the biochemical parameters, all parameters were affected during infection then restored after the 12th day post infection. However, in the prophylactic groups, showed mild clinical signs and the blood pictures and biochemical parameters were nearly like the control negative without infection.ConclusionDZN at a quarter dose of standard DZ produced the same outcomes as DZ at 10 mg/mL. Furthermore, DZN does not impair the typical safety of diclazuril in treated chicks.

Transmission-blocking activities of artesunate, chloroquine, and methylene blue on Plasmodium vivax gametocytes.

Plasmodium vivax is now the main cause of malaria outside Africa. The gametocytocidal effects of antimalarial drugs are important to reduce malaria transmissibility, particularly in low-transmission settings, but they are not well characterized for P. vivax. The transmission-blocking effects of chloroquine, artesunate, and methylene blue on P. vivax gametocytes were assessed. Blood specimens were collected from patients presenting with vivax malaria, incubated with or without the tested drugs, and then fed to mosquitos from a laboratory-adapted colony of Anopheles dirus (a major malaria vector in Southeast Asia). The effects on oocyst and sporozoite development were analyzed under a multi-level Bayesian model accounting for assay variability and the heterogeneity of mosquito Plasmodium infection. Artesunate and methylene blue, but not chloroquine, exhibited potent transmission-blocking effects. Gametocyte exposures to artesunate and methylene blue reduced the mean oocyst count 469-fold (95% CI: 345 to 650) and 1,438-fold (95% CI: 970 to 2,064), respectively. The corresponding estimates for the sporozoite stage were a 148-fold reduction (95% CI: 61 to 470) and a 536-fold reduction (95% CI: 246 to 1,311) in the mean counts, respectively. In contrast, high chloroquine exposures reduced the mean oocyst count only 1.40-fold (95% CI: 1.20 to 1.64) and the mean sporozoite count 1.34-fold (95% CI: 1.12 to 1.66). This suggests that patients with vivax malaria often remain infectious to anopheline mosquitos after treatment with chloroquine. Use of artemisinin combination therapies or immediate initiation of primaquine radical cure should reduce the transmissibility of P. vivax infections.

Anti-coccidial efficacy of Enteromorpha prolifera polysaccharide in indigenous chickens of Northwest Ethiopia.

A variety of bioactive compounds isolated from various botanical sources have been found to have therapeutic and immunotherapeutic effects on chicken coccidiosis. This study aimed to evaluate the anti-coccidial potential of Enteromorpha prolifera polysaccharide (EP) in indigenous chickens in Northwest Ethiopia. A total of 78 male indigenous chickens were used for this study. The study had two treatment groups: (1) the EP non-supplemented group (those fed on diets without EP and Eimeria oocyst inoculated) and (2) the EP group (those receiving diets supplemented with 400mgEP/kg diet and Eimeria oocyst inoculated). Each treatment group had five replications. Following fourteen days of EP supplementation, 1.5×104 oocysts of mixed Eimeria species were inoculated into individual birds. EP-supplemented chicken showed significantly lower (p<0.05) oocyst counts compared to non-supplemented ones on 9 and 11 days post-challenge. In addition, chickens in the EP-supplemented group showed less severe lesion scores, with an average score of 1.33. Chickens that received EP showed a maximum of 27.27% protection against lesions. In contrast, the non-supplemented chickens had a lower percentage of protection (19.83%). The maximum anti-coccidial index value (146.98) was obtained from EP-supplemented chickens. Chickens in the EP-supplemented group exhibited a significantly higher (p<0.05) weight gain. Overall, the inclusion of EP in chickens' diets shows promise as a potential anti-coccidial strategy. However, additional research is required to explore the mechanisms by which EP in chickens' diet could involve in increasing the protection ability of chickens against coccidiosis.

Traditional Chinese medicine formulation ChangQing compound has significant therapeutic effects on chickens infected with Eimeria tenella

Coccidiosis poses a significant challenge to the poultry industry. However, the excessive and improper use of anticoccidial drugs and vaccines has led to resistance and food safety concerns. Consequently, traditional Chinese herbs have garnered attention as a potentially safer and more effective alternative. ChangQing compound derived from various Chinese herbal medicines is a promising anticoccidiosis agent, but its therapeutic effects have not been comprehensively evaluated. This study aimed to assess the therapeutic efficacy of ChangQing Compound against Eimeria tenella-induced coccidiosis in chickens on the basis of physiological indicators, cecum lesions, and changes in microbial diversity. The comparison with the positive control group revealed the average weight gain (AWG) and anticoccidial index (ACI) of the chicks were significantly higher, in contrast, the feed conversion ratio (FCR), cecal lesion score (CLS), and oocyst count per gram of cecal content (OPG) were significantly lower (P<0.05). Notably, AWG (138.87 g), OPG (0.57 × 106), ACI (177.92), and FCR (2.51) reflected the significant therapeutic effect of the 2.5 g/L ChangQing compound treatment (CQM). Histological sections showed that the cecal villus damage and intestinal wall swelling were minimal in the CQM, consistent with the CLS (0.73). Additionally, the 2.5 g/L ChangQing compound treatment effectively prevented the decrease of red blood cells, platelets, and hemoglobin, while promoting the release of anti-inflammatory factors interleukin-10 and interleukin-4, and inhibiting the pro-inflammatory factors interferon-γ and interleukin-17. The microbial community structure in the CQM was most similar to that of the negative control group. In summary, ChangQing compound had multiple positive effects (e.g., promoting weight gain, alleviating anemia, suppressing coccidial proliferation, reducing intestinal damage, modulating immunity, and maintaining intestinal microbiota homeostasis). The study results may be relevant to developing a novel strategy for the clinical management of coccidiosis.

Effects of the inclusion of two extracts derived from the olive industry on growth performance, antiparasitic protection, and antioxidant activity in broiler chicken diets from 0 to 45 d

The objective of the present study was to investigate the optimal inclusion rate of 2 independent extracts with different properties derived from the olive industry [triterpenic acid extract (TAE) and a polyphenol extract (PE)] on productive performances in broiler chickens from 0 to 45 d under challenging conditions. In addition, antiparasitic protection of the TAE was evaluated at d 21 and d 28 through intestinal scoring and oocyst counts, as well as the blood antioxidant activity of the PE at d 45. Wood shavings as bedding material came from a commercial farm with a coccidia load sufficient to create a subclinical coccidiosis situation with minor macroscopic lesions, and a nutritional challenge was imposed using poor raw materials to cause intestinal dysbiosis. There were 9 dietary treatments (8 replicates/treatment and 15 broiler chickens/pen), a positive control (PC) supplemented with commercial coccidiostat (Na monensin), 4 increasing concentrations of TAE (30, 60, 90, and 120 ppm), and 4 increasing concentrations of PE (10, 20, 30, and 40 ppm). For the overall experiment the PC had greater average daily gain (ADG) and average daily feed intake (ADFI) (P < 0.001) than the mean of TAE treatments. Besides, the ADG, body weight, and ADFI increased linearly throughout the whole experiment as the TAE level of the feed increased. With respect to the anticoccidial activity, the 120 ppm TAE treatment showed greater concentration of E. acervuline DNA copies at 21 d than the 30 ppm TAE treatment (P < 0.05), the rest of the treatments being intermediate. Concerning the PE treatments, for the overall experiment, ADG was the greatest in the PC treatment (P < 0.001), and the ADFI was similar in the PC treatment to the mean of PE treatments. There was no effect of the PE on antioxidant activity. In conclusion, under the conditions of this study, the inclusion of TAE does not reach the productive performance indicators achieved by a commercial coccidiostat in our intestinal challenge situations. Also, the inclusion of PE has a positive effect on productive performance on the overall period.

Anticoccidial potentials of Azadirachta indica ethosomal nanovesicle in broiler chicks

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

Orange (Citrus sinensis) essential oil inclusion in high-energy diets for feedlot lambs: productivity, eating behavior, carcass characteristics, rumen morphometry, and fatty acid profile of the meat

This study evaluated the effect of different orange essential oil (OEO) inclusion rates on live weight gain, eating behavior, carcass characteristics, morphology of the ruminal epithelium, and fatty acid profile in the meat of feedlot lambs. Forty uncastrated Dorper × Santa Inês ram lambs with an initial average body weight of 21.8 ± 4.7 kg and average age of 86 ± 15 days were allocated to one of five dietary treatments in a randomized complete block design. Dietary treatments consisted of a 90:10 concentrate-to-forage ratio total mixed ration supplemented as follows: 1. non-additive supplementation (Control), and 2. additive supplementation with 100, 500, and 1000 mg OEO/kg diet DM (OEO100, OEO500, and OEO1000) or with 25 mg sodium monensin/kg diet DM (MON). The feeding lasted 84 d. Supplementation with OEO increased linearly dry matter intake (DMI), growth rate and feed efficiency (FE). Because of the linear increases in growth rate and the efficiency of energy utilization of the diet, lambs receiving OEO exhibited a greater (increasing linear effect) hot carcass weight (HCW), Longissimus muscle area (LMA), subcutaneous fat thickness (SFT), and body wall thickness (BWT) than lambs fed with Control. Lambs fed MON had lower DMI, growth rate and FE than Control and OEO. Compared to Control and OEO supplemented, lambs that received MON showed lower HCW, LMA, SFT, and BWT. Lambs fed with MON had lower oocyst counts than lambs fed with all other treatments. Lambs fed with MON spent more time eating and ruminating, with higher chewing rates than lambs fed all other diets. Rumen morphometry was unaffected by dietary treatment. The OEO supplementation increased the sum of monounsaturated fatty acids, improved the human health promotion index (HP index), and reduced the thrombogenicity index in the meat relative to lambs fed the MON treatment. Under the conditions in which the experiment was conducted, the inclusion of up to 1000 g/kg diet DM in high-energy finishing diets promotes DMI and improved growth performance and FE. Improvements in the carcass (HCW, LMA, and BTF) with OEO supplementation were mainly due to improvements in growth rate rather than effects on gain composition. Based on growth performance and carcass characteristics, OEO was a superior feed additive to sodium monensin. The OEO supplementation has a discreet effect on the fatty acid profile of the meat, but it is sufficient to improve the HP index. These findings highlight its potential as an effective additive for enhancing lamb productivity.

Infectivity of Plasmodium parasites to Aedes aegypti and Anopheles stephensi mosquitoes maintained on blood-free meals of SkitoSnack

BackgroundAedes and Anopheles mosquitoes are responsible for tremendous global health burdens from their transmission of pathogens causing malaria, lymphatic filariasis, dengue, and yellow fever. Innovative vector control strategies will help to reduce the prevalence of these diseases. Mass rearing of mosquitoes for research and support of these strategies presently depends on meals of vertebrate blood, which is subject to acquisition, handling, and storage issues. Various blood-free replacements have been formulated for these mosquitoes, but none of these replacements are in wide use, and little is known about their potential impact on competence of the mosquitoes for Plasmodium infection.MethodsColonies of Aedes aegypti and Anopheles stephensi were continuously maintained on a blood-free replacement (SkitoSnack; SS) or bovine blood (BB) and monitored for engorgement and hatch rates. Infections of Ae. aegypti and An. stephensi were assessed with Plasmodium gallinaceum and P. falciparum, respectively.ResultsReplicate colonies of mosquitoes were maintained on BB or SS for 10 generations of Ae. aegypti and more than 63 generations of An. stephensi. The odds of engorgement by SS- relative to BB-maintained mosquitoes were higher for both Ae. aegypti (OR = 2.6, 95% CI 1.3–5.2) and An. stephensi (OR 2.7, 95% CI 1.4–5.5), while lower odds of hatching were found for eggs from the SS-maintained mosquitoes of both species (Ae. aegypti OR = 0.40, 95% CI 0.26–0.62; An. stephensi OR = 0.59, 95% CI 0.36–0.96). Oocyst counts were similar for P. gallinaceum infections of Ae. aegypti mosquitoes maintained on SS or BB (mean ratio = [mean on SS]/[mean on BB] = 1.11, 95% CI 0.85–1.49). Similar oocyst counts were also observed from the P. falciparum infections of SS- or BB-maintained An. stephensi (mean ratio = 0.76, 95% CI 0.44–1.37). The average counts of sporozoites/mosquito showed no evidence of reductions in the SS-maintained relative to BB-maintained mosquitoes of both species.ConclusionsAedes aegypti and An. stephensi can be reliably maintained on SS over multiple generations and are as competent for Plasmodium infection as mosquitoes maintained on BB. Use of SS alleviates the need to acquire and preserve blood for mosquito husbandry and may support new initiatives in fundamental and applied research, including novel manipulations of midgut microbiota and factors important to the mosquito life cycle and pathogen susceptibility.Graphical

Patterns of gastrointestinal parasite infections in bighorn sheep, Ovis canadensis, with respect to host sex and seasonality

Males and females in sexually dimorphic species show differences in their physiology and behaviour due to differences in energetic investment into reproduction and soma. This means that the two sexes may show different patterns of parasitism at different times of the year. In this study, we evaluate the abundance of fecal eggs and larvae of 5 parasite types (Strongyles, Nematodirus spp., Marshallagia marshalli., Protostrongylus spp. lungworms, and Eimeria spp.) in relation to season and sex in Rocky Mountain bighorn sheep (Ovis canadensis). We use fecal egg counts (FEC) as a proxy for infection intensity. Parasite FECs differed between male and female bighorn sheep and varied with season. We found pronounced fluctuations in fecal egg counts of various parasite species in males and females across different seasons and reproductive stages. Strongyle counts were significantly higher during late gestation and lactation/summer, and particularly pronounced in males. Nematodirus counts were highest during late gestation in females and during the rut in males. Marshallagia counts peaked during late gestation in females and during the rut in males. Protostrongylus spp. lungworm counts were highest during late gestation in females and in males during lactation/summer and the rut. Eimeria oocyst counts varied across seasons, with higher counts in males during the rut and in females during winter and late gestation. Additionally, significant differences in Strongyle counts were observed between coursing and tending rams, with tending rams exhibiting higher counts. We discuss why the sexes might differ in FECs and suggest that differences between FECs of the parasites across seasons may be due to different life cycles and cold tolerance of the parasites themselves.

Silymarin effectively prevents and treats Eimeria tenella infection in chicks

Silymarin, a botanical medicine derived from milk thistle seeds and is known to improve chicken growth and gut health when added to the feed. However, its role in the prevention and treatment of chicken coccidiosis remains unclear. This study investigated the efficacy of various doses of silymarin in preventing and treating Eimeria tenella infection in chicks. A total of 180 one-day-old specific pathogen-free chicks were randomized into six groups of 30 chicks each, no treatment (NC group); E. tenella infection (CC group); diclazuril medication during d 14 to 21 and E. tenella infection (DC group); and three groups infected with E. tenella and administered low, medium, or high doses of silymarin during d 12 to 21. All groups except NC were infected with E. tenella on d 14, with indicators observed on d 21. The growth performance was higher in the silymarin treated groups than that in the CC group, and the oocyst count per gram of manure, blood stool, and cecal lesion scores decreased. The medium-dose silymarin group exhibited the best treatment effect. Additionally, the silymarin groups displayed improved histological, morphology, and intestinal barrier integrity. The amounts of proinflammatory factors and harmful bacteria in the cecum were also reduced. Additionally, the activity of serum and cecal antioxidant enzymes, as well as the abundance of beneficial gut microbiota, increased in the cecum. In conclusion, this study demonstrated that silymarin can prevent and treat E. tenella infections. These data provide a scientific and conceptual basis for the development of a botanical dietary supplement from silymarin for the treatment and control of coccidiosis in chicks.

Effects of Starter Diet Energy Concentration on Nutrient Digestibility and Subsequent Growth Performance and Meat Yields of Broilers under Two Coccidiosis Control Programs.

An experiment was conducted to evaluate the live performance, processing characteristics, and apparent ileal digestibility (AID) of nutrients and energy (IDE) in broilers under two coccidiosis control programs (CCP) and fed three starter diet energy levels. Treatments were a factorial arrangement of CCP [in-feed diclazuril (ACD) or vaccinated after hatch (VAC)] and three starter diet energy levels [3008 (standard), 3058 (moderate), and 3108 (high) kcal/kg apparent MEn] achieved with different soybean oil concentrations. Birds were reared in floor pens (12 per pen) and received experimental starter diets from 0 to 18 d and common grower and finisher diets to 43 d. At d 11, VAC birds had higher (p < 0.05) excreta oocyst counts and lower (p < 0.05) plasma carotenoids, nutrient AID, and IDE than ACD birds. From 0 to 18 and 0 to 31 d, VAC decreased (p < 0.05) body weight gain and increased (energy × CCP, p < 0.05) feed conversion ratio of birds fed the moderate and high-energy diets but not for those fed the standard energy diet. From 0 to 43 d, VAC only increased the feed conversion ratio of birds fed the moderate-energy starter diet (energy × CCP, p < 0.05). Carcass yields were lower (p < 0.05) for VAC birds than for ACD birds, and interactive effects (p < 0.05) were observed for wing yield. In summary, increasing dietary lipid concentration to account for Eimeria-induced reductions in lipid digestibility during the starter period of coccidiosis-vaccinated broilers may exacerbate, rather than ameliorate, these impacts on bird performance.

A comparative study on the vector competence of Anopheles stephensi from geographically distinct malarious and non-malarious urban areas in India to the malarial parasite, Plasmodium vivax.

Anopheles stephensi is responsible for the transmission of malaria in urban areas. Vector competence of An. stephensi from a non-malarious (Coimbatore) and highly malarious (Chennai) urban area were investigated to find out the reason for the non-transmission of malaria in Coimbatore. Vector competence (Susceptibility/refractoriness) of An. stephensi mosquitoes from Chennai (Malarious) and Coimbatore (Non-malarious), Tamil Nadu, India to Plasmodium vivax (Chennai) were investigated. Bioassays were carried out concurrently in both these strains by artificial membrane feeding technique using the same malaria infected blood. An. stephensi were dissected to observe infection in the midgut and salivary glands. The parasite infection, oocyst and sporozoite positivity rate, the oocyst load, correlation between male-female gametocyte ratio and infection, and Survival Analysis of parasitic stages during sporogony were analyzed and compared. The overall infection rate was 45.8 and 41.2 per cent in Chennai and Coimbatore. Oocyst count ranged from 1-80 and 1-208 respectively and not statistically significant. Oocyst positivity was high from Day 8-21in both strains. The Mean Survival Day (MSD) for oocyst was Day 14 in both strains. Sporozoite was observed in four experiments in each of the strains and the MSD for sporozoites was Day 20 and Day 17 in Chennai and Coimbatore. An. stephensi of Chennai and Coimbatore are equally susceptible to P. vivax infection and the non-transmission of malaria in Coimbatore can be attributed to external factors such as the presence of preferential breeding habitat, vector density, vector survival, and weather. The only difference observed was the comparatively shortened oocyst maturation time in the Coimbatore strain which requires further investigation.

Influence of deep-litter bedding materials on environmental and welfare-related factors in boar studs

In recent years, it has become increasingly difficult for artificial insemination (AI) centers to procure high-quality bedding materials. The aim of this study was to investigate influences of bedding materials on selected environmental and welfare-related aspects in breeding boars. Including seasonal changes, two trial runs were conducted in winter (T1) and summer (T2) to compare five deep-litter bedding materials (wood shavings (WS), hemp straw (HS), linen straw (LS), spelt husks (SH), and regional wood shavings (RWS)). The cleanliness of the boar pens was visually assessed at the end of T1 and T2 using a 4-point scale (1 = >75%, 2 = 75–51%, 3 = 50–25%, and 4 = <25% clean surface). Simultaneously, a body position score for each boar was assessed (1 = lying on flank, 2 = lying on belly, 3 = sitting, and 4 = standing). Temperatures of bedding at 5 cm and 15 cm depth were determined using a thermometric probe at week 6 and 16 after initial bedding replacement. Ambient temperature and relative humidity were measured at the same time. Simultaneously, fecal samples were collected and analyzed for oocysts in T1. To include flies as a health hazard and nuisance, sticky traps were evaluated in T2. Generalized linear mixed models and a two-way ANOVA were calculated for the statistical evaluation of observations. Cleanliness evaluation showed differences among bedding materials in T1 (P = 0.004) but not in T2 (P > 0.05). There were no differences in the body position score among the materials. WS and RWS were generally cooler at the start of T1 and T2. The greatest difference of 7°C in means was detected between RWS and SH at the start of T2 and 15 cm depth (P ≤ 0.001). Oocyst counts revealed no difference among bedding materials in T1. In T2, fly numbers differed for time of bedding period and for the interaction term between time of bedding period and material (P ≤ 0.05). In conclusion, the results demonstrate clear differences between materials in terms of temperature, cleanliness of pens (T1), and partially fly burden (T2). Considering heat is a great stressor for most animals, we favor wooden materials as deep-litter bedding for AI boars compared to others due to lower heat development during the bedding period. Moreover, we recommend avoiding replacement of deep-litter bedding during hot summer months in AI centers to reduce excessive heat development.

Validating the use of a newly developed cinnamaldehyde product in commercial broiler production

Essential oils (EOs) have been considered as an alternative to antibiotics for animal production. In the current study, 4 trials were conducted on a commercial broiler farm to investigate the effects of dietary supplementation of an encapsulated cinnamon EO product (NE-OFF) on the bird growth performance, gut health, and gene expression in the ileum, spleen, and liver relating to the host response to heat and other stresses, including potential NE challenge. In each trial, approximately 30,000 Cobb or Ross broilers were randomly allocated to 4 treatments: a raised without antibiotics (RWA) commercial diet as positive control, an adjusted RWA commercial diet as negative control, and the negative control diet supplemented with 2 different dosages of NE-OFF, which was added during feed pelleting. Although the final average body weight did not differ significantly among treatment groups, birds fed NE-OFF had an increased ratio of villus height and crypt depth in the jejunum, and reduced fecal oocyst counts. Trial 2 was conducted in the summer and had a necrotic enteritis (NE) outbreak. The supplementation of NE-OFF reduced the NE incidence and bird mortality. The samples from Trial 2 were hence selected for the analyses of Clostridium perfringens and NetB toxin gene abundance in the ileum, and host responses. The C. perfringens population appeared to be positively correlated with the NetB gene abundance. The gene expression analysis suggested that NE-OFF supplementation improved nutrient absorption and transportation as well as antioxidant activities to help the birds against stress. These on-farm trial results support the hypothesis that the use of NE-OFF as a feed additive can improve bird gut health and performance in commercial broiler production, especially for preventing NE outbreaks when birds are under stress.

Comparison of necrotic enteritis effects on growth performance and intestinal health in two different meat-type chicken strains Athens Canadian Random Bred and Cobb 500

Chickens have undergone genetic improvements in the past few decades to maximize growth efficiency. However, necrotic enteritis (NE), an enteric disease primarily caused by C. perfringens, remains a significant problem in poultry production. A study investigated the differences in intestinal health between the nonselected meat-type chicken Athens Canadian Random Bred (ACRB) and the modern meat-type Cobb 500 broilers (Cobb) when challenged with experimental NE. The study utilized a 2 × 3 factorial arrangement, consisting of two main effects of chicken strain and NE challenge model (nonchallenged control, NC; NE challenge with 2,500/12,500 Eimeria maxima oocysts + 1 × 109C. perfringens, NE2.5/NE12.5). A total of 432 fourteen-day-old male ACRB and Cobb were used until 22 d (8 d postinoculation with E. maxima on d 14, dpi), and the chickens were euthanized on 6 and 8 dpi for the analysis. All data were statistically analyzed using a two-way ANOVA, and Student's t-test or Tukey's HSD test was applied when P < 0.05. The NE12.5 group showed significant decreases in growth performance and relative growth performance from d 14 to 20, regardless of chicken strain (P < 0.01). The ACRB group exhibited significant decreases in relative body weight and relative body weight gain compared to the Cobb group from d 14 to 22 (P < 0.01). On 6 and 8 dpi, both NE challenge groups showed significant decreases in intestinal villus height to crypt depth ratio, jejunal goblet cell count, and jejunal MUC2 and LEAP2 expression (P < 0.01). Additionally, the NE12.5 group had significantly higher intestinal NE lesion score, intestinal permeability, fecal E. maxima oocyst count, intestinal C. perfringens count, and jejunal IFNγ and CCL4 expression compared to the NC group (P < 0.05). In conclusion, NE negatively impacts growth performance and intestinal health in broilers, parameters regardless of the strain.

Bromelain can reduce the negative effects of a subclinical necrotic enteritis in broiler chickens

This study was conducted to examine the efficacy of a bromelain-based supplementation coded ANR-pf on growth performance and intestinal lesion of broiler chickens under necrotic enteritis (NE) challenge. A total of 540 Ross 308 day-old male chicks were randomly allocated into 6 treatments of 6 replicates. The bromelain formulation was delivered to chickens through gavaging and/or in drinking water method twice, on d 8 and 13. Non-challenged groups included (1) without or (2) with the specific bromelain formulation gavaged at 0.8 mL/kg. NE-challenged groups included (3) without the specific bromelain formulation; (4) gavaged with 0.4 mL/kg; (5) gavaged with 0.8 mL/kg and (6) supplemented with 0.8 mL/kg via drinking water. Birds were challenged with Eimeria spp. on d 9 and Clostridium perfringens (NE-18 strain) on d 14 and 15. On d 14 and 19, fresh faecal contents were collected for the determination of oocyst counts. Intestinal lesion scores were determined on d16. Performance and mortality were recorded throughout the entire experiment. Among challenged groups, birds received additive via drinking water had higher weight gain (WG) compared to the remaining groups (P < 0.001) in the grower phase and had lower FCR compared to 0.4 mL/kg inoculated group in the grower and finisher phases (P < 0.001). Bromelain supplementation via drinking water improved the WG of challenged birds, similar to that of the non-challenged birds (P < 0.001), and lowered FCR compared to other challenged groups (P < 0.001). Non-challenged birds and birds that received bromelain formulation in drinking water did not have lesions throughout the small intestine whereas challenged birds, either un-supplemented or supplemented with bromelain via inoculation route recorded similar lesion score levels in the jejunum. At d19, birds received bromelain in drinking water had lower faecal oocyst numbers compared to challenged birds without additive (P < 0.001). In conclusion, bromelain administration via drinking water could ameliorate the negative impacts of NE-infection in broilers by improving performance, lowering the oocyst numbers and lesion scores.

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

For years, there has been an increasing interest in natural alternatives to the conventional coccidiostats applied as feed additives, which have been used for decades to prevent coccidiosis in poultry and fattening rabbits. This study aimed to compare the possible anticoccidial effects of oregano oil to the established substance diclazuril in growing rabbits. The control group (CG) received a non-supplemented basal compound feed, to which either diclazuril (1 mg/kg; DG) or oregano oil (75 mg/kg; OG) was added. In each of the three trials, subgroups of 50 rabbits each were assigned to one of the three experimental groups (CG, DG and OG). Natural Eimeria infection was monitored weekly by fecal oocyst counts and Eimeria species identification following sporulation. Additionally, the performance parameters were determined at the middle and the end of the trials, and the deceased rabbits were subjected to necropsy. Neither oocyst excretion nor the performance parameters differed significantly between the three experimental groups. Eimeria media, Eimeria magna, Eimeria perforans and Eimeria exigua were identified as the occurring species. The highest animal losses (16.0%) occurred in the OG, while the losses were 12.7% in the DG and 12.0% in the CG. However, these differences were not statistically significant. Overall, neither diclazuril nor oregano oil was superior to the non-supplemented feed. This underlines the importance of diagnostics, as this study’s results indicate that in the absence of the highly pathogenic Eimeria species, economic rabbit rearing and fattening is achievable without the use of coccidiostats.

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.

Dietary Spirulina effects in Eimeria-challenged broiler chickens: growth performance, nutrient digestibility, intestinal morphology, serum biomarkers, and gene expression.

This study investigated the growth performance, nutrient utilization, and intestinal health responses of Eimeria-challenged broiler chickens to dietary Spirulina (Arthrospira platensis). On day 1, birds were assigned to 2 diets supplemented with Spirulina (0 or 5g/kg) in a randomized complete block design. The birds within each diet were divided into 2 Eimeria-challenge groups (challenge or no-challenge) and that resulted in a 2 × 2 factorial arrangement with 2 levels each of Spirulina and challenge on day 14. On day 15, the birds in the challenge or no-challenge groups were orally gavaged with a solution containing Eimeria oocysts or 1% PBS, respectively. Samples were collected on days 21 and 26 (6- and 11-d post-infection; dpi). Data collected from days 1 to 26 were analyzed using the MIXED procedure of SAS. Birds that were fed Spirulina-supplemented diets had increased (P < 0.05) BW gain, gain-to-feed ratio, and total tract retention nitrogen from days 14 to 21. The ileal villus perimeter and area, serum catalase, HMOX1 and SOD1 jejunal abundance were all increased (P < 0.05) in birds fed Spirulina-supplemented diets on day 21 (6 dpi). However, there was no effect on bone ash or oocyst count. From days 21 to 26, there was a tendency (P = 0.059) for a Spirulina × Challenge interaction on the BW gain of birds. Moreover, dietary Spirulina addition increased (P < 0.05) serum catalase, total antioxidant capacity, ileal villus perimeter, tibia bone ash, and the relative mRNA expression of HMOX1, SOD1, claudin 1, and TNFα in the jejunal mucosa of birds on day 26 (11 dpi). On both 6 and 11 dpi, the Eimeria challenge negatively (P < 0.05) impacted growth performance, gut morphology, and the relative mRNA expression of genes. Overall, assessing the impact of Spirulina in broilers revealed its positive antioxidant, immune-modulating, and health benefits. However, its dietary addition did not completely reverse the Eimeria-induced effects in these birds. Ultimately, this study outlines the positive properties of dietary Spirulina beyond its use in the diet of healthy broiler chickens.

Prevalence and parasite burden of oocysts in captive and free-living saffron finches, Sicalis flaveola.

The saffron finch, Sicalis flaveola, a passerine bird, can be found in nearly all Brazilian territory and is also raised in captivity. The objective of this work was to determine the prevalence and load of oocysts in captive saffron finches in the municipality of Campos dos Goytacazes, state of Rio de Janeiro and in free-living saffron finches in the municipality of Eugenopolis, state of Minas Gerais. In this analysis, 30 captive and 30 wild birds were assessed. Feces eliminated in a 24-hour period were collected and weighed to determine the number of oocysts per gram of feces (OoPG). Statistical analyses were performed using Microsoft Excel and GraphPad Prism Software. All birds in the present study were positive for one or more species of coccidia. Captive birds had a mean total oocyst count higher than that of wild birds. No significant differences in OoPG counts were observed when comparing males and females or captive and wild birds. We can conclude that due to the fact that birds both eat and defecate in their cages, it is essential to keep them as clean as possible, since captive birds have a higher prevalence of coccidia.