Mean Oocyst Count Research Articles

Modulation of Eimeria spp. parasite load on productivity parameters in lambs fed with babassu byproduct.

This study investigated the modulation of Eimeria spp. parasite load and its impact on productivity parameters in lambs fed varying levels of babassu by-product (BBP). Twenty-four Dorper × Santa Inês lambs naturally infected with Eimeria spp. were divided into four groups and assigned to dietary treatments with increasing levels of BBP inclusion: Control group (0% BBP; n = 6), G1 (5% BBP; n = 6), G2 (10% BBP; n = 6), and G3 (15% BBP; n = 6). Fecal oocyst counts, dry matter intake (DMI), average daily gain (ADG), and apparent digestibility coefficients were monitored throughout the experiment. Results revealed that 9.5% BBP inclusion was associated with the lowest mean oocyst count per gram of feces, without compromising ADG. Nine Eimeria species were identified, with E. crandallis, E. parva and E. ovinoidalis being the most prevalent. Principal component analysis revealed a negative correlation between Eimeria spp. infection intensity and lamb performance, with higher BBP inclusion levels being associated with improved DMI, ADG, and digestibility. These findings suggest that dietary BBP at 9.5% inclusion effectively modulates Eimeria spp. parasite load in lambs while maintaining productivity. Although the exact mechanisms require further investigation, these results highlight BBP as a promising natural alternative for coccidiosis management in sheep production. This natural, sustainable approach offers a promising strategy for coccidiosis management in sheep, particularly in tropical and subtropical production systems.

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.

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.

The controverted therapeutic efficacy of Allium sativum and Artemisia herba-alba extracts on Cryptosporidium-infected mice.

Cryptosporidiosis has become an issue of great interest being life-threatening among immunocompromised hosts worldwide. This study explored the curative effect of Allium sativum (garlic) and Artemisia herba-alba ethanolic extract versus Nitazoxanide drug on both immunocompetent and immunosuppressed-Cryptosporidium experimentally-infected mice. One hundred male Swiss albino mice were divided into the following groups: (GI) non-infected non-treated group, (GII) infected non-treated group, (GIII) garlic treated group, (GIV) A. herba-alba treated group, (GV) Nitazoxanide treated group, each group subdivided into two subgroups (a) Immunocompetent, (b) immunosuppressed. The assessment was performed by parasitological counting of fecal oocysts, histological examination of intestinal tissue, immunological detection of interferon-gamma levels in mice sera, and ultrastructural study by transmission electron microscopy. Garlic and A. herbal-alba extracts showed a decrease in the mean oocyst counts through all days of follow-up. This was associated with significant up-regulation of interferon-gamma cytokine levels in serum and histological improvement in intestinal tissues of mice compared to control groups and the results were confirmed by transmission electron microscopy. The highest efficacy was obtained by garlic, then by A. herbal-alba extracts followed by Nitazoxanide treated group; where the immunocompetent groups showed better improvement than immunosuppressed ones. Garlic has a perfect effect as a promising therapeutic agent against Cryptosporidiosis and therefore validates their traditional use in parasitic infections. Accordingly, it may offer a good option for cryptosporidium treatment in immunocompromised patients. They could be used as a natural safe product for the preparation of a new therapeutic agent.

Characterization and bioactivities of M. arvensis, V. officinalis and P. glabrum: In-silico modeling of V. officinalis as a potential drug source

In current study the pharmaceutically active herbs was used against coccidiosis, caused by a protozoan: Eimeria, lead to $ 3 billion loss annually. The aqueous and methanolic extracts of whole plants were applied in-vitro to assess sporulation inhibition (spi) assay and calculated the inhibitory concentration (IC50). For in-vivo study 9 groups of 14 day old broiler chicks were infected with Eimeria tenella and three groups were treated different concentrations of methanolic extracts of Verbena officinalis and Polygonum glabrum post infection. The mean weight gain, oocyst count, diarrhea, biochemical tests, hematology, and histopathology of all groups were analyzed. The herbs were characterized by antioxidant assay, phytochemical screening, Fourier transmission and infrared (FT-IR), Ultra Violet-visible (UV–Vis) spectroscopy and Gas chromatography and mass spectroscopy (GC–MS). The GC–MS identified phyto-compounds of V. officinalis were docked with S-Adenosyl methionine (SAM) synthetase. The in-vitro study revealed that V. officinalis and P. glabrum have minimum IC50 of 0.14 and 12 mg/ml respectively. The in-vivo experiment showed that V. officinalis had significantly high anticoccidial potential with significant hematological profile like drug treated controls. The histology of treated chicks also showed recovery in the studied tissues. The antioxidant assay showed that V. officinalis have 4.19U/mg Superoxide dismutase (SOD) and 33.96 µM/mg Glutathione (GSH) quantities. The chemical characterization confirmed the presence of large number of organic compounds, however Flavonoids found only in V. officinalis, which suggests the anticoccidial potential of V. officinalis because flavonoids as antagonist of thiamine (Prinzo, 1999), because it promotes the carbohydrate synthesis required. Strychane, 1-acetyl-20a-hydroxy-16-methylene has best binding of with target protein with lowest binding score (-6.4 Kcal/mol), suggests its anticoccidial potential in poultry.

The potential therapeutic effect of Nigella sativa and Zingiber officinale extracts versus Nitazoxanide drug against experimentally induced cryptosporidiosis in laboratory mice.

In this study, the potential anti-cryptosporidial effect of Nigella sativa (black seeds) and Zingiber officinale (ginger) alcoholic extracts versus Nitazoxanide (NTZ) medication was investigated in immunosuppressed (IS) laboratory mice. Parasitological, histopathological studies were used to assess their therapeutic efficacy. Serum level and tissue expression percentage of IFN-γ was also used. Nigella extract succeeded to reduce the mean oocyst counts in the feces of immunosuppressed mice followed by NTZ. Ginger-treated ones showed the lowest reduction percentage. Nigella sativa showed the best results in terms of restoring the normal architecture of ileal epithelium in histopathological sections stained with H&E. NTZ treatment sub-groups showed mild improvement, followed by ginger-treated mice, which showed a slight improvement in small intestine microenvironment. A significant substantial rise in serum and intestinal tissue IFN-γ cytokine levels were recorded in Nigella subgroups compared to those of NTZand ginger respectively. According to our findings Nigella sativa outperformed Nitazoxanide in terms of anti-cryptosporidial effectiveness and regeneration characteristics revealing a promising medication. When compared to the commonly used Nitazoxanide medication or Nigella extracts, the outcomes of ginger extract were suboptimal.

Ameliorative Effect of Neem Leaf and Pomegranate Peel Extracts in Coccidial Infections in New Zealand and V-Line Rabbits: Performance, Intestinal Health, Oocyst Shedding, Carcass Traits, and Effect on Economic Measures.

Simple SummaryCoccidiosis, one of the most contagious diseases among domestic rabbits, negatively affects production and results in massive economic losses. This study evaluates the therapeutic efficacy of treatment with aqueous neem leaf extract and ethanolic pomegranate peel extract (PPE) individually and in combination on the intestinal coccidiosis caused by Eimeria spp. in New Zealand white and V-line (VL) rabbits. Rabbits from two breeds were divided into ten equal groups (five groups each for NZ and VL). All rabbits were inoculated with Eimeria spp. oocysts except for the rabbits in the first group (G1) (negative control). The remaining groups were: G2, positive control, G3, treated with neem leaf extract, G4, treated with pomegranate peel extract (PPE), and G5, treated with a combination of neem leaf extract and PPE. Our results showed that the use of neem leaf and/or pomegranate peel extract for both breeds resulted in improved growth performance, a significant reduction in mean oocyst count, no mortalities, an anticoccidial index > 120, and significantly improved economic efficiency measures when compared to the positive control group.Healthy, weaned, coccidial-free male rabbits from two breeds (New Zealand white (NZ) and V-line (VL)) were divided into 10 equal groups (5 groups each for NZ and VL) (3 replicates/group, 6 rabbits/replicate, 18 rabbits/group). All rabbits were inoculated with 5 × 104 Eimeria spp. oocysts (E. intestinalis (67%), E. magna (22%), and E. media (11%)) except for the rabbits in the first group (G1), which were inoculated with a sterile solution and served as a negative control. The remaining four groups were treated as follows: G2, no treatment/positive control, G3, treated with neem leaf extract, G4, treated with pomegranate peel extract (PPE), and G5, treated with a combination of neem leaf extract and PPE. For both breeds, our results showed that the use of neem leaf and/or pomegranate peel extract resulted in improved growth performance, with a significant improvement in relative feed conversion ratio (FCR) compared to the positive control groups, which recorded the worst values, as well as a significant (p ≤ 0.05) reduction in mean oocyst count compared to the positive control groups. We also observed downregulation of mRNA levels of IL-1βα, IL6, and TNF-α in the herbal treatment groups compared with the mRNA levels of these genes in the positive control groups. Herbal treatment with neem leaf and/or pomegranate peel extracts had positive effects on the NZ and VL rabbits experimentally infected with mixed Eimeria species, as evidenced by their healthy appearance, good appetite, no mortalities, an anticoccidial index > 120, and a significantly higher total return and net profit when compared to the positive control groups of both breeds. In NZ rabbits, the treatment with neem leaf extract alone (G3) or in combination with PPE (G5) recorded the most efficient economic anticoccidial activity.

Evaluation of possible prophylactic and therapeutic effect of mefloquine on experimental cryptosporidiosis in immunocompromised mice.

Cryptosporidiosis is an imperative global health concern. Unfortunately, Nitazoxanide (NTZ) (the nowadays drug of choice) is not effective in treatment of immunocompromised patients. We aimed to assess the possible anti-cryptosporidial prophylactic and therapeutic effects of Mefloquine (MQ) on infected immunosuppressed murine models. Mice were divided into five groups; GI: received Mefloquine (400mg/kg/day), GII: received NTZ (100mg/kg/bid), GIII: received a combination, half dose regimen of both drugs, GIV: infected untreated and GV: non-infected untreated. Each treated group was divided into three subgroups; Ga prophylaxis (PX), thereafter infection, Gb first and Gc second treatment doses. Assessment was done by parasitological, histopathological and serological techniques. A significant oocyst clearance was detected in all prophylactically treated groups. GIa showed 77% reduction of the mean oocyst count in stool while GIb and GIIIc showed100% oocyst clearance. Histopathologically, the ileocecal sections from GIV showed loss of brush borders with marked villous atrophy. GIa induced a moderate improvement of those pathological changes. Moreover, the villi in GIb and GIIIc retained their normal appearance with minimal inflammatory cells. Serum interferon gamma levels showed highly significant increases in GI&GIII compared to GIV while a non-significant increase was observed in GIIa only. On the contrary, serum interleukin-17 levels showed a highly significant down-regulation in all treated groups in comparison to GIV. This study proved a marvelous effect of MQ-PX on cryptosporidiosis in immunosuppressed mice and thus it could be introduced as one of the most promising re-purposed prophylactic and therapeutic anti-cryptosporidial agents.

Potential therapeutic and prophylactic effects of Asafoetida in murine cryptosporidiosis.

Cryptosporidium parvum is an important coccidian parasite that could infect the intestine, respiratory and biliary tracts of man and animals. This study aims to test the potential therapeutic and prophylactic effects of a natural herbal agent (Asafoetida) versus the nowadays drug of choice (Nitazoxanide). Fifty bred female, white Albino mice of CDI strain were divided into 5 groups; group I (GI): immunosuppressed, infected with C. parvum and treated with Asafoetida, group II (GII): immunosuppressed, prophylactically treated with Asafoetida for 7days prior to infection, group III (GIII): immunosuppressed, infected and treated with Nitazoxanide, group IV (GIV): immunosuppressed and infected (Positive control), group V (GV): immunosuppressed and non infected (Negative control). Parasitological and histopatholgical examinations of the stool, ileocaecal and liver specimens were performed for the study groups. GI showed reduction of the mean oocyst count in stool with improvement of the pathological changes at the ileocaecal region with preservation of hepatic architecture. Results of GI were better than GII and GIV but not as good as GIII. GII showed the least improvement among the test groups. GIII showed the best response between the test groups. GIV show no statistical significant difference between the mean oocyst count in the mice stool at the time of infection and 7days after infection. It was therefore concluded that Asafoetida is a promising natural therapeutic and prophylactic agent against cryptosporidiosis while, Nitazoxanide is the best chemotherapeutic agent against cryptosporidiosis.

DOWNREGULATION OF TOLL-LIKE RECEPTOR 4 AND ACUTE PHASE CYTOKINES MEDIATED DEXAMETHASONE IMMUNOSUPPRESSANT MECHANISM DURING CRYPTOSPORIDIUM-PARVUM INFECTION

TLRs in enterocytes play an important role in protecting the mucosal surface by promoting the innate inflammatory immune response following infection. Cryptosporidium parvum generally causes a short-term diarrheal illness that resolves spontaneously in immunocompetent hosts. But, in immunocompromised hosts, (e.g. on steroid therapy), it may cause a life-threatening, chronic, cholera-like illness. The mechanisms by which steroids reduced the host resistance toC. parvum infection are poorly understood. It was hypothesized that steroid may interfere with TLR activation and reduced proinflammatory cytokines production required for early infection containment. To test this hypothesis, sixty C57BL/6 mice were equally divided into three subgroups; G1 was daily given intraperitoneally dexamethasone (DEX) for 14 days before oocyst inoculation and throughout the study. G2 was non-immunosuppressed mice. G1 & G2 were inoculated intragastrically with C. parvum (106 oocysts). G3 was retained as naive non-infected control. Length and severity of infections were determined by monitoring oocyst shedding in fecal pellets using acid-fast (Ziehl-Neelsen) stained smear prepared from fresh pellets, by counting the number of oocysts in 10 microscopic fields under x100 for each mice group. Expression of TLR4 was assessed by immunohistochemistry, serum of proinflammatory cytokines level was determined by ELISA. The results showed that DEX immunosuppressed mice developed chronic cryptosporidiosis that lasted until the study end. Non-immunosuppressed mice developed a patent infection and the majority of them overcame the infection by the 21st day. The mean oocyst count was significantly higher in the immunosuppressed mice than in non-immunosuppressed ones, with a longer patent period in immunosuppressed mice. Expression of TLR4 was significantly increased in mice gut post-infection. Expression of TLR was significantly decreased in DEX immunosuppressed infected mice, with a significant decr ease was in proinflammatory cytokines serum levels compared to non-immunosuppressed ones.

DOWNREGULATION OF TOLL-LIKE RECEPTOR 4 AND ACUTE PHASE CYTOKINES MEDIATED DEXAMETHASONE IMMUNOSUPPRESSANT MECHANISM DURING CRYPTOSPORIDIUM-PARVUM INFECTION

TLRs in enterocytes play an important role in protecting the mucosal surface by promoting the innate inflammatory immune response following infection. Cryptosporidium parvum generally causes a short-term diarrheal illness that resolves spontaneously in immunocompetent hosts. But, in immunocompromised hosts, (e.g. on steroid therapy), it may cause a life-threatening, chronic, cholera-like illness. The mechanisms by which steroids reduced the host resistance toC. parvum infection are poorly understood. It was hypothesized that steroid may interfere with TLR activation and reduced proinflammatory cytokines production required for early infection containment. To test this hypothesis, sixty C57BL/6 mice were equally divided into three subgroups; G1 was daily given intraperitoneally dexamethasone (DEX) for 14 days before oocyst inoculation and throughout the study. G2 was non-immunosuppressed mice. G1 & G2 were inoculated intragastrically with C. parvum (106 oocysts). G3 was retained as naive non-infected control. Length and severity of infections were determined by monitoring oocyst shedding in fecal pellets using acid-fast (Ziehl-Neelsen) stained smear prepared from fresh pellets, by counting the number of oocysts in 10 microscopic fields under x100 for each mice group. Expression of TLR4 was assessed by immunohistochemistry, serum of proinflammatory cytokines level was determined by ELISA. The results showed that DEX immunosuppressed mice developed chronic cryptosporidiosis that lasted until the study end. Non-immunosuppressed mice developed a patent infection and the majority of them overcame the infection by the 21st day. The mean oocyst count was significantly higher in the immunosuppressed mice than in non-immunosuppressed ones, with a longer patent period in immunosuppressed mice. Expression of TLR4 was significantly increased in mice gut post-infection. Expression of TLR was significantly decreased in DEX immunosuppressed infected mice, with a significant decr ease was in proinflammatory cytokines serum levels compared to non-immunosuppressed ones.

Evaluation of Saccharum officinarum L. bagasse-derived polysaccharides as native immunomodulatory and anticoccidial agents in broilers

Coccidiosis is one of the most important protozoal diseases of the poultry industry, inflicting heavy economic losses in the form of high mortality and morbidity in affected birds. Under these circumstances, the development of nonchemical consumer-friendly strategies for its effective control is of paramount importance. Therefore, this study was conducted to evaluate the sugarcane (Saccharum officinarum L.) bagasse-derived polysaccharides as native immunomodulatory and anticoccidial agents in commercial broilers. Polysaccharides were recovered from sugarcane bagasse (PSCB) and analyzed by high-performance liquid chromatography (HPLC). Five different sugars including melezitose, maltose, glucose, mannose, and fructose were detected in hydrolyzed solution of PSCB. The isolated PSCB were orally administered to the broilers in three graded doses ranging from 10 to 50mg/kg of body weight/day for 3 consecutive days, i.e., fifth through seventh days of life. Results showed significantly enhanced (p<0.05) lymphoproliferative and humoral responses to T-cell mitogen (PHA-P) and sheep red blood cells (SRBCs) in PSCB-administered chickens. In a challenge experiment, percent protection and daily weight gains were significantly higher (p<0.05), whereas mean oocyst counts and lesion scores were lower (p<0.05) in PSCB-administered chickens as compared to control. ELISA showed that PSCB significantly enhanced (p<0.05) antibody titers against the Eimeria species used for the induction of infection in chickens of PSCB-administered and control groups. In conclusion, PSCB showed the potential to modulate the immune responses in industrial broiler chickens with subsequent protection against coccidial infection.

Transmission-blocking activity is determined by transmission-reducing activity and number of control oocysts in Plasmodium falciparum standard membrane-feeding assay

Malaria transmission-blocking vaccines (TBVs) are potentially helpful tools for malaria eradication. The standard membrane-feeding assay (SMFA) is considered one of the “gold standard” assays for TBV development. However, lack of consensus in reporting results from SMFA has made it very challenging to compare results from different studies. Two main readouts, % inhibition in mean oocyst count per mosquito (TRA) and % inhibition in prevalence of infected mosquitoes (TBA), have been used widely.In this study, we statistically modeled the oocyst data in SMFA using data from 105 independent feeding experiments including 9804 mosquitoes. The model was validated using an independent data set that included 10,790 mosquitoes from 110 feeding studies. The model delineates a relationship between TRA, the mean oocyst count in the control mosquitoes (mo-contl), and TBA. While TRA was independent from mo-contl, TBA values changed depending on mo-contl. Regardless of monoclonal or polyclonal antibodies tested, there were strong concordances between observed TBA and predicted TBA based on the model using mo-contl and observed TRA. Simulations showed that SMFA with lower true control means had increased uncertainty in TRA estimates. The strong linkage between TBA, TRA and mo-contl inspired creation of a standardized TBA, a model-based TBA standardized to a target control mean, which allows comparison across multiple feeds regardless of mo-contl.This is the first study showing that the observed TBA can be reasonably predicted by mo-contl and the TRA of the test antibody using independent experimental data. This study indicates that TRA should be used to compare results from multiple feeds with different levels of mo-contl. If a measure of TBA is desired, it is better to report standardized TBA rather than observed TBA. These recommendations support rational comparisons of results from different studies, thus benefiting future TBV development.

Effect of butyrate, clopidol and their combination on the performance of broilers infected with Eimeria maxima

1. The effect of butyric acid glycerides (BAGs) with and without clopidol (CLP) on Eimeria maxima on growth and associated biochemical variables was investigated in broiler chickens.2. One-day-old chicks were divided into 6 equal groups (Gps) of 30 chicks each; each group was subdivided into 6 equal subgroups. Gp 1 was not infected and not treated. Chicks in Gp 2 were not infected and fed on a ration mixed with 4 g BAGs/kg for 6 successive weeks. Chicks of the other groups were directly inoculated intra-crop with 1 × 104 sporulated oocysts of E. maxima at 14 d of age. Gp 3 was infected and not treated. Chicks in the remaining three groups were given diets mixed with the tested drugs for 6 successive weeks. Gp 4 was fed on a diet mixed with CLP (125 g/kg). Gp 5 was given a diet mixed with BAGs (4 g/kg diet). Gp 6 was fed on a diet mixed with both BAGs (4 g/kg diet) and CLP (125 g/kg).3. Birds in Gps 5 and 6 showed a reduction in the mean oocyst count, lesion scores and developmental stages in the lamina propria and improved growth and biochemical variables. BAG supplementation enhanced growth and production of healthy broilers.4. It was concluded that BAGs were a useful supplement in broiler diets as an alternative to growth promoters and antimicrobial drugs.

Observations on the epidemiology and interactions between myxomatosis, coccidiosis and helminth parasites in a wild rabbit population in Scotland

A study of the epidemiology of myxomatosis and the protozoan liver parasite, Eimeria stiedae, in a population of wild rabbits in Scotland from 1977 to 2010 is reported. Rabbits were collected on a monthly basis resulting in a total of 5,337 animals examined for the infections. The investiga- tion showed that within any 1 year over the 34 years of the investigation the percentage of rabbits with myxomatosis varied between 0 and 24 %, while for E. stiedae infections fluctuated between 3 and 42 %. There were strong seasonal trends in the prevalence of myxomatosis with over 16 % being infected in September and October, and for E. stiedae ,p eaks of over 40 % of livers infected were recorded in July. From 2007 to 2010, faeces were also examined for coccidia oocysts and parasitic nematode eggs. Rabbits infected with the myx- oma virus had mean oocyst counts of 73,665 per gram faeces, while rabbits not infected with the myxoma virus had counts of 31,952 oocysts per gram. Comparable figures for nematode faecal egg counts were 911 per gram in myxomatosis-infected animals and 427 per gram in uninfected animals. The elevated nematode faecal egg counts in rabbits with myxomatosis re- flects increased worm burdens already reported, but the ele- vated counts of coccidial oocysts have not previously been reported. This would suggest that myxomatosis could com- promise rabbit immunity to nematodes and coccidia.

Efficacy of Toltrazuril 5 % Suspension against Eimeria bovis and Eimeria zuernii in Calves and Observations on the Associated Immunopathology

16 Calves were each infected with suspensions containing a mixture of approximately 230,000 Eimeria bovis and 70,000 E. zuernii oocysts, which resulted in detection of oocysts in faeces of 12 of 16 calves by day +14 after infection. On day +14 after infection calves were either treated (n = 8) with toltrazuril at 15 mg/kg body weight or with a placebo. Observations were made on the clinical condition, faecal score and liveweight of calves daily from one day post infection (pi) until 24 days pi when all calves were euthanised and examined post mortem. Samples were collected from ileum and colon for histological, immunohistochemical and gene expression studies. The study demonstrated an efficacy of toltrazuril for the treatment of E. bovis and E. zuernii infections in calves reaching 99 % (based on arithmetic mean oocyst counts in faeces) within three days of treatment and remaining at or above this level for six days. Toltrazuril did not have a significant effect on the pattern and extent of immune cellular infiltration in the mucosa of ileum and colon, but the expression of the genes coding IL-2, IL-10 and TNF-α in the ileum and TNF-α in the colon were elevated in calves treated with toltrazuril. Higher levels of oocyst shedding were significantly associated with lower expression of genes coding for IL-2, IL-10 and higher IP-10. It is concluded that toltrazuril is effective for the treatment of coccidiosis due to E. bovis and E. zuernii in calves and enables the development of a normal or enhanced immune response to infection.

Coccidial infections in housed lambs: oocyst excretion, antibody levels and genetic influences on the infection

Faecal Eimeria oocyst excretion, body weights, humoral antibodies against E. ovinoidalis sporozoite antigen and related heritabilities were determined in housed Merinoland sheep lambs throughout a period of 100 days after birth in Germany. Altogether 10–11 Eimeria spp. were found. Cumulative incidences of E. ovinoidalis and E. weybridgensis/ crandallis increased rapidly resulting in almost 100% incidence in 8 weeks old lambs. In the other species, the cumulative incidence increased more continuously. Except for E. granulosa oocysts of all species had been excreted at last once until day 30. By far the highest oocyst counts (OpG) were observed with E. ovinoidalis, followed by E. weybridgensis/ crandallis. High counts were limited to the period of 5–8 weeks after birth. In the other Eimeria species oocyst counts persisted at comparatively low levels until the end of the observation period although their proportion of the total counts increased with age of the lambs. Time courses of oocyst excretion suggest an early onset of effective immunity to the major Eimeria spp., which differed for the minor species. Mean and maximum oocyst counts and body weights of the lambs were inversely correlated suggesting negative effects of the infection on the lamb's performance. High mean antibody levels on day 7 after birth dropped until day 40 and increased subsequently again. There were no indications that maternal antibodies were protective. Antibody levels on day 40 after birth were positively correlated with oocyst counts in the faeces whereas those determined on day 80 were independent of infection parameters. Heritabilities of log 10 OpG were not significantly different from 0 up to an age of 60 days. Later estimated values were between 0.54 and 0.79 suggesting that immune protective effects rather than innate effects determining disease susceptibility are under genetic influence.

Prevalence of coccidia and gastrointestinal nematode infections in cross bred goats in the dry areas of Sri Lanka

The prevalence and intensity of oocysts of coccidia, particularly Eimeria species, and eggs of gastrointestinal nematodes in kids (2–4 months), young goats (5–12 months) and adult goats (>1 year) were determined in five large herds managed extensively in five villages in the dry zone. Of the representative samples examined, oocysts were found in 88% of kids, 91% of young goats and 83% of adults. Seven species of Eimeria were identified in faecal samples by salt flotation. Eimeria ninakohlyakimovae (31%), E. alijevi (29%) and E. arloingi (21%) were the most common species in all age categories. Other species encountered were E. christenseni (7%), E. jolchijevi (6%), E. hirchi (3%) and E. aspheronica (1%). Gastrointestinal nematode eggs were found in 89% of the kids, 94% of the young goats and 84% of the adult goats. Identification of gastrointestinal nematodes revealed Haemonchus contortus (90%) followed by Oesophogostomum spp. (8.5%) and Trichostrongylus spp. (1%) in all three age categories examined. Both Eimeria and gastrointestinal nematodes were found in 77% of the kids, 86% of the young goats and 71% of adult goats. The mean oocyst counts per gram of faeces in kids, young goats and adult goats were 9728, 1946, and 2667, respectively. The oocyst counts were not different significantly between age groups ( P>0.05). The mean egg counts per gram of faeces in kids, young goats and adult goats were 1217, 1641 and 1092, respectively. The egg counts in kids were significantly lower than that in young goats ( P<0.05). The intensity of Eimeria and gastrointestinal nematode infections between herds were significantly different ( P<0.01).

Efficacy of halofuginone lactate in the prevention of cryptosporidiosis in suckling calves

The efficacy of halofuginone lactate in the prevention of cryptosporidiosis in suckling calves was evaluated in a multicentre, control versus placebo, randomised, double.blind clinical trial. Seventy-eight six- to 48- hour-old...

The prevalence of coccidian species in sheep in Kars Province of Turkey.

Coccidia were detected in the faeces of 556 out of 592 sheep (93.9%) in sheep in Kars province. The prevalence of coccidiosis was significantly higher (p < 0.01) in young (97.9%) and immature sheep (96.6%) than in adult sheep (90.2%). Mixed infections were widespread (71.5%). Ten species of Eimeria were recognized. These species (and their prevalences) were: Eimeria ovinoidalis (47.7%), E. bakuensis (E. ovina) (46.6%), E. parva (37.1%), E. granulosa (27.7%), E. ahsata (23.4%), E. pallida (23.2%), E. faurei (15.1%), E. intricata (13.9%), E. crandallis (13.7%) and E. punctata (2.3%). Eimeria punctata is reported in sheep from Turkey for the first time. The mean oocyst count from infected animals was 3451 +/- 409 opg (range 50-117,600). The mean was higher (9529 +/- 502) in young sheep. Differences in the counts from young, immature and adult sheep were statistically significant (p < 0.01). However, no clinical cases of coccidiosis were encountered.