| the effect of immunity on the early events in the life-cycle of eimeria tenella in the caecal mucosa of the chicken. | a comparison was made between the early events (asexual stages) in the life-cycle of eimeria tenella in specifically immunized and control chickens. particular attention was paid to the quantitative aspects and to the transport of sporozoites within intra-epithelial lymphocytes (iel) from the enterocytes of the surface epithelium to the enterocytes of the crypts. there was a moderate decrease in the number of parasites initially seen in the mucosa of the immune birds, suggesting that some of the ... | 1984 | 6718052 |
| the effects of sym. triazinones on developmental stages of eimeria tenella, e. maxima and e. acervulina: a light and electron microscopical study. | the development of three chicken coccidia (eimeria tenella, e. acervulina and e. maxima) was studied by means of light and electron microscopy. one group of chickens infected with 6000-20,000 oocysts received a single dose of 5 mg/kg body weight (comparable to approx. 25 ppm in the feed) bay vg 7183 or bay vi 9142 orally (on day 3 or 4 p.i.), whereas others received two doses (on days 3 and 4 or on days 4 and 5 p.i.). the animals were killed on days 3, 4, 5, 6 and 7 p.i. and parts of the mucosa ... | 1984 | 6720030 |
| characterization of rhoptry proteins of eimeria tenella sporozoites: antigenic diversity of rhoptry epitopes within species of the genus eimeria and among three asexual generations of a single species, e. tenella. | rhoptry organelles from sporozoites of the apicomplexan parasite eimeria tenella contain at least 60 independent polypeptides that can be resolved by two-dimensional gel electrophoresis. rhoptries from three species of eimeria that infect chickens share very few antibody cross-reactive epitopes, and there is poor conservation of epitopes among three distinct asexual generations of zoites within the developmental life cycle of a single parasite, e. tenella. | 1994 | 7523296 |
| the influence of nutrient density of broiler rations on the effective dose of anticoccidial drugs. | anticoccidial drugs were added to diets formulated with a nutrient density of 1479 kcal/lb and 24% protein or with 80% of those energy and protein levels (low density) to determine whether rate of feed intake influences efficacy of drugs in broilers infected with coccidiosis. in four experiments with monensin, broilers receiving 60 or 100 ppm of monensin in the lower-density ration consumed more feed per unit of gain but gained less weight than those on the control diet. coccidiosis (eimeria ten ... | 1984 | 6721805 |
| epidemiological studies of coccidiosis in the domesticated fowl (gallus gallus): i. the fate of ingested oocysts of eimeria tenella during the prepatent period in susceptible chicks. | a small proportion of sporulated and unsporulated coccidial oocysts (eimeria tenella) inoculated per os into domesticated fowl were recovered intact within about one day, well within the usual 5-day ¿prepatent period.¿ recovery rates of sporulated oocysts were ca. 2-9% from chicks inoculated at all ages tested from 2 to 28 days. from chicks within the same age range, the recovery rates for unsporulated oocysts were ca. 15-21%. the higher recovery rates of unsporulated oocysts indicated that they ... | 1995 | 7550444 |
| effect of dietary raw soybeans on coccidiosis in chickens. | six battery experiments determined the effect of feeding raw soybeans (rsb) in corn-soybean diets on coccidiosis in broiler chickens. the experimental design represents a 2 x 3 factorial arrangement of treatments with three dietary levels of incorporation of rsb (0, 50, and 100%), and chickens either infected or uninfected. the coccidial species tested singularly were eimeria acervulina, eimeria maxima, eimeria necatrix, eimeria brunetti, and eimeria tenella. with all species of eimeria a signif ... | 1995 | 7603956 |
| effect of selenium and vitamin e on the development of immunity to coccidiosis in chickens. | six experiments were conducted using broiler chickens to study the effect of selenium (se) or vitamin e supplementation of a corn-soybean meal diet on the immune response to coccidiosis. immunized chickens fed diets supplemented with .25 ppm se or 100 iu vitamin e/kg of diet had increased body weight gain and feed intake and a tendency for lower feed conversion ratio than chickens fed unsupplemented diet after a challenge with 150,000 oocysts of eimeria tenella. in two experiments, chickens fed ... | 1984 | 6739404 |
| comparative studies on the efficacy of sulphachlorpyrazine and toltrazuril for the treatment of caecal coccidiosis in chickens. | the therapeutic efficacy of sulphachlorpyrazine and toltrazuril against experimentally induced eimeria tenella infection was compared in battery and floor pen raised broiler chickens. in the battery studies, both drugs prevented coccidiosis-related mortality and decrease of weight gain to a similar degree, but toltrazuril was more effective in reducing intestinal lesions and faecal scores, when treatments were initiated 24 h postinfection. when medication was delayed until 72 h after inoculation ... | 1995 | 7657461 |
| coccidiosis: a radiological study of sulphaquinoxaline distribution in infected and uninfected chickens. | using scintillation counting and autoradiographical techniques, the whole-body distribution in week-old uninfected chickens of the anticoccidial agent sulphaquinoxaline (sq) labelled with 35s was established at various time intervals after a single oral dose either alone or following continuous in-feed medication with unlabelled sq, and after a single intravenous dose. the distribution was also established in chickens infected with the coccidia eimeria acervulina or e. tenella, after a single or ... | 1995 | 7674452 |
| eimeria tenella, eimeria necatrix, and eimeria adenoeides: peripheral blood leukocyte response of chickens and turkeys to strains adapted to the turkey embryo. | the peripheral blood leukocyte responses of chickens and turkeys inoculated with one of three strains of a chicken eimeria species adapted to the turkey embryo with their respective parent lines, or with e. adenoeides of the turkey were studied. the adapted lines tended to cause hematological changes in chickens and turkeys similar to those caused by e. adenoeides. these parasites caused the most significant increases in large mononuclear white blood cells = (monocytes) in both chickens and turk ... | 1984 | 6745387 |
| pyrazolo[3,4-d]pyrimidine ribonucleosides as anticoccidials. 1. synthesis and activity of some nucleosides of purines and 4-(alkylthio)pyrazolo[3,4-d]pyrimidines. | the finding that 6-(methylthio)-9-beta-d-ribofuranosyl-9h-purine (6) was more toxic to the avian coccidium, eimeria tenella, than to embryonic chick liver host cells in vitro prompted the synthesis and testing of analogues of this compound. it was revealed that the beta-d-ribofuranosyl moiety was an important structural feature and that several types of 2-substituents in the purine ring decreased efficacy, as did 3-deaza and 8-aza ring modifications of 6. in contrast, the pyrazolo[3,4-d]pyrimidi ... | 1982 | 7086819 |
| studies on the stage of action of ionophorous antibiotics against eimeria. | sporozoites of eimeria tenella were treated with different anticoccidial drugs in vitro and their subsequent viability was tested by inoculating them into chicken embryos. monensin, salinomycin, lasalocid, and arprinocid, at concentrations between 0.01 and 1.0 micrograms/ml, greatly reduced sporozoite viability as judged by mortality, hemorrhage and specific lesions in the embryo chorioallantois. monensin was also effective in reducing the viability of sporozoites of e. mivati and e. tenella as ... | 1982 | 7097439 |
| eimeria maxima gametocyte antigens: potential use in a subunit maternal vaccine against coccidiosis in chickens. | affinity-purified gametocyte antigens (apga) from eimeria maxima, emulsified in freund's adjuvant, were injected intramuscularly into breeding hens on two or three occasions. as a result, progeny of the immunized hens were partially immune to infection with e. maxima, eimeria tenella and eimeria acervulina (with a reduction in total oocyst output of 45-63% as compared with progeny of untreated hens). thus, apga in freund's adjuvant appears to have great potential as part of a maternally applied ... | 1995 | 7793129 |
| surface changes induced by immune serum on eimeria tenella sporozoites and merozoites. | the surface of merozoites and sporozoites of eimeria tenella was affected by incubation with e. tenella-immune chicken serum (ics). normal chicken serum (ncs) and heat-inactivated ics had no effect on the pellicular surface of either developmental stage. sporozoites formed surface bulges or swellings after 10 min of incubation with ics, and by 15 min postincubation, the morphology of the sporozoites was distorted by a surface coating of fibrinous material. merozoites exposed to ics were similarl ... | 1982 | 7131354 |
| responses to prolonged selection for resistance and susceptibility to acute cecal coccidiosis in the auburn strain single comb white leghorn. | selection in the parental auburn strain leghorn (a line) for resistance (r line, 13 filial generations) and susceptibility (s line, 7 filial generations) to acute cecal coccidiosis (acc) caused by eimeria tenella resulted in a sixfold difference in the acc mortality rates of the two lines. relaxation of selection for resistance in line rr, derived entirely from r line, resulted in gradual regression of the acc mortality rate toward that of the parental a line nonselected control. progress of sel ... | 1982 | 7163113 |
| mucosal transport of eimeria tenella in the cecum of the chicken. | a study of the early life history of eimeria tenella with the electron microscope confirmed that sporozoites do not directly enter the enterocytes of the crypts, in which they develop, but are carried there by host cells. however, these cells are not macrophages, as previously thought, but intraepithelial lymphocytes. the evidence presented demonstrates that sporozoites first penetrate surface enterocytes and then enter intraepithelial lymphocytes that leave the epithelium, pass through the lami ... | 1982 | 7175614 |
| development and characterization of chicken-chicken b cell hybridomas secreting monoclonal antibodies that detect sporozoite and merozoite antigens of eimeria. | chicken-chicken b cell hybridomas that secrete monoclonal antibodies (mab) detecting antigens located at the anterior tip of the sporozoites of eimeria acervulina have been produced. peripheral blood lymphocytes (pbl) obtained from chickens infected with e. acervulina were fused with a thymidine-kinase deficient (tk-) chicken b cell line. hybridomas secreting mab binding to the sporozoite antigens of e. acervulina were selected using an elisa. two stable hybridomas, whose mab were designated as ... | 1994 | 7862608 |
| selective labeling of intracellular parasite proteins by using ricin. | studies focused on the synthesis by intracellular parasites of developmentally regulated proteins have been limited due to the lack of a simple method for selectively labeling proteins produced by the parasite. a method has now been developed in which ricin is employed to selectively inhibit host-cell protein synthesis. ricin is a heterodimer composed of two subunits, a lectin and a glycosidase, and it binds to terminal galactose residues on the cell surface via the lectin. following endocytosis ... | 1995 | 7892277 |
| [freund's complete adjuvant and the infectiousness of eimeria tenella oocysts for chickens]. | | 1982 | 7179732 |
| potentiation of ionophorous anticoccidials with dihydroquinolines: battery trials against eimeria tenella in chickens. | seven battery tests, employing a total of 1344 hybro cockerels, were conducted in order to study the interaction between ionophorous anticoccidials and a new dihydroquinoline-type antioxidant known as duokvin. a significant, non-selective, toxic interaction was established, resulting in growth depression and improved anticoccidal efficacy against eimeria tenella and e. mitis in these chickens. the duokvin itself showed no appreciable activity against the coccidia. the adverse effects of the inte ... | 1994 | 7928071 |
| coccidial parasites from the chicken: discrimination of different populations of eimeria tenella by dna hybridisation. | four dna probes that are reiterated several times within the genome of eimeria tenella have been used to derive restriction fragment length polymorphism patterns that are characteristic for different laboratory-maintained or recently isolated populations. three of the four probes hybridised only to dna from e tenella whereas probe b209 also hybridised to dna from both e praecox (strongly) and e acervulina (more weakly). the results of this study confirm the usefulness of dna probes for taxonomic ... | 1994 | 7973081 |
| effect of eimeria tenella infection on resistance to salmonella typhimurium colonization in broiler chicks inoculated with anaerobic cecal flora and fed dietary lactose. | this study evaluated the effect of eimeria tenella infection on salmonella typhimurium colonization of broiler chicks following oral inoculation with anaerobic cecal flora either alone or with a treatment of 10% dietary lactose. the number of chicks colonized by s. typhimurium was significantly lower (p < 0.05) in groups inoculated with cecal flora with or without the dietary lactose treatment than in control groups. in addition, significantly fewer s. typhimurium organisms were isolated from th ... | 1994 | 8002901 |
| effects of infection of eimeria tenella, e. acervulina, and e. maxima upon salmonella typhimurium infection in chickens. | three experiments were conducted to examine whether salmonella typhimurium infection is enhanced by concurrent infection with eimeria tenella, e. acervulina, or e. maxima. there were two groups in each experiment: birds infected with a daily oral dose of approximately 1 x 10(4) cfu of s. typhimurium for 5 days after coccidial infection and birds infected with s. typhimurium alone with the similar exposure schedule. chickens were necropsied 7, 10, and 14 days after coccidial infection. the number ... | 1984 | 6371754 |
| effect of levamisole on the immune response of chickens to infection with eimeria tenella. | the effect of levamisole on the immunization to coccidiosis in chickens was investigated. the protection to the challenge infection with eimeria tenella was higher in those chickens immunized by inoculating a small number of oocysts of e. tenella and administered orally with levamisole at dosage levels of 1.25 to 5 mg/kg body weight, once daily for 3 days, one week after immunization than in immunized and levamisole-untreated or unimmunized and levamisole-treated chickens. the activities of peri ... | 1984 | 6375211 |
| growth of salmonella typhimurium in the caecum of gnotobiotic chickens with eimeria tenella. | gnotobiotic chickens infected with eimeria tenella (5 x 10(4) oocysts per bird) received an oral inoculation of 100 salmonella typhimurium two, four, six or eight days after coccidial infection at four days old. when s typhimurium was given two or four days after e tenella infection, s typhimurium counts in the caecal contents were similar to the counts in birds infected with s typhimurium alone. when s typhimurium was given six or eight days after e tenella infection, counts of the organism wer ... | 1984 | 6390591 |
| eimeria tenella infection enhances salmonella typhimurium infection in chickens. | three experiments were conducted to investigate the effects of concurrent infections of salmonella typhimurium and eimeria tenella on establishment of salmonella infection in chickens. there were four groups in all experiments: noninfected controls, birds infected with 50,000 e. tenella oocysts, birds infected with approximately 10(4) s. typhimurium, and birds infected with a combination of e. tenella s. typhimurium. in the first experiment with three identical trials of 80 birds each, chickens ... | 1981 | 7329903 |
| effects of chicken anti-eimeria tenella serum on the phagocytosis of sporozoites and merozoites by chicken peritoneal macrophages. | | 1980 | 7382238 |
| effects of lasalocid (.0125%) in combination with roxarsone on lesion reduction and oocyst suppression in chickens infected with eimeria tenella field isolates. | lasalocid (.0125%) alone and combined with roxarsone (.005%) was evaluated for its effect on lesion reduction and oocyst suppression in thirty-five controlled replicated battery experiments, using in excess of 6200 broiler chickens. the chickens were inoculated with field isolates containing predominantly eimeria tenella species. lasalocid (.0125%) used alone exhibited a high degree of anticoccidial activity. lasalocid (.0125%) fed in combination with roxarsone (.005%) showed, in addition to hig ... | 1980 | 7393845 |
| [biochemical evaluation of the therapeutic effectiveness of coccidin in coccidiosis of hens]. | 20-day old chicks were infected with eimeria tenella, treated with coccidin (250 mg/kg) and free amino acids of the femoral muscle tissues were studied. the infection of chicks was accompanied with metabolism disorders of all amino acids of the muscle tissue excluding leucine, methionine, tyrosine and phenylalanine. during the treatment of infected chicks with coccidin the level of free amino acids re-established within 10 days. this preparation affected most of all metabolism of alanine, isoleu ... | 1980 | 7422351 |
| in vitro interleukin-1 and tumor necrosis factor-alpha production by macrophages from chickens infected with either eimeria maxima or eimeria tenella. | we measured the in vitro production of interleukin-1 (il-1) and tumor necrosis factor-alpha (tnf- ) by macrophages from chickens during and immediately following an infection with one of two different species of eimeria, e. maxima and e. tenella. quantitatively, the amounts of il-1 produced during each infection were nearly identical regardless of the oocyst dose of each parasite. tnf production followed a biphasic pattern of increased production with the first peak associated with the pathogene ... | 1993 | 8225766 |
| a comparative study of the biological activities of arprinocid and arprinocid-1-n-oxide. | the livers of chickens maintained on a diet containing an effective in vivo level (70 ppm) of arprinocid, an anticoccidial agent, were found to contain 0.64 ppm of this drug and 0.33 ppm of a metabolite, arprinocid-1-n-oxide. when arprinocid was tested against eimeria tenella in cultures of chick kidney epithelial cells, which do not metabolize the drug appreciably, it was found to block the development of the parasite with an id50 of 20 ppm. in the same test system, the 1-n-oxide blocks coccidi ... | 1980 | 7442720 |
| new anticoccidial antibiotics, ws-5995 a and b. i. isolation and characterization. | ws-5995 a, b and c are produced by a new strain of streptomyces designated streptomyces auranticolor. these antibiotics were purified by solvent extraction followed by chromatography on silica gel and then crystallized. ws-5995 a (c19h12o6, m.p., 289 approximately 291 degrees c) and ws-5995 b (c19h14o6, sublimation at 300 degrees c) protect chickens from infection with eimeria tenella, a species of coccidia, which produces morbidity or mortality in chickens. ws-5995 c (c19h14o 7, m.p. 288 approx ... | 1980 | 7451360 |
| immunocytochemical and immunoelectron microscopy study of dendritic cells in the caecal tonsils of chickens infected with eimeria tenella. | in the present study s-100 protein containing cells in the caecal tonsil were investigated, both at light microscopic and at electron microscopic levels, after oral coccidia inoculation (eimeria tenella). the birds were infected with a single (day 0) or two (days 0 and 21) infective doses of 500 oocysts. immunoelectron reactivity for s-100 protein was demonstrated in infected chickens, but not in controls. it was found in follicular dendritic cells and interdigitating dendritic cells which were ... | 1993 | 8256432 |
| [eimeria tenella and eimeria acervulina: an antigenic stimulation in vitro of cells from immune chickens induced by adoptive transfer of protection against avian coccidiosis]. | the transfer of 5 x 10(7) or 10(8) spleen cells from e tenella-infected chickens to virgin animals after 12-20-h in vitro stimulation with whole sporozoite homogenates confers significant protection to recipients. the oocyst contents of ceca on d 7 post-infection with 20,000 e tenella oocysts were (1.33 +/- 1.10) x 10(6) in chickens which received 5 x 10(7) immune cells after 20-h in vitro stimulation and (4.64 +/- 2.85) x 10(6) in chickens receiving 5 x 10(7) stimulated cells from normal chicke ... | 1993 | 8260962 |
| studies on anticoccidial agents. 13. synthesis and anticoccidial activity of nitropyridine-2- and -3-sulfonamides and derivatives. | eight nitropyridinesulfonamides and pyridinesulfonamide n-oxides as their bioisosteres were prepared and evaluated for anticoccidial activity. of these compounds, 2-, 4- and 5-nitropyridine-3-sulfonamides and pyridine-2- and -3-sulfonamide n-oxides were found to be active against eimeria tenella. thus, the relative positions, ortho or meta, of the substituents in nitropyridine-3-sulfonamides and pyridinesulfonamide n-oxides are important for anticoccidial activity. n-substituted analogues of 5-n ... | 1980 | 7452692 |
| anticoccidial efficacy of semduramicin. 1. evaluation against field isolates by dose titration in battery tests. | semduramicin (aviax), a novel polyether ionophore, was titrated in a series of five battery tests at 20, 25, and 30 ppm in feed to determine the optimum level for use. twelve-day-old broiler chicks were medicated for 48 h prior to inoculation in each 9-day test. the inocula included monospecific field isolates of eimeria tenella, eimeria brunetti, eimeria necatrix, and eimeria maxima, and a mixture of these species with eimeria acervulina and eimeria mitis. the numbers of oocysts inoculated were ... | 1993 | 8265494 |
| eimeria tenella: clinical effects in partially immune and susceptible chickens. | chickens made partially immune to e. tenella infection exhibited cecal lesions after challenge. some of the chickens had cecal lesions of severity similar to those of birds having their first infection with the parasite. the presence of severe cecal lesions in the partially resistant birds was not accompanied by lowered body weight gain or packed erythrocyte volumes and prothrombin time was not extended. it is suggested that there are at least three stages of immunity to e. tenella; birds may be ... | 1980 | 7465497 |
| chicken tumor necrosis-like factor. i. in vitro production by macrophages stimulated with eimeria tenella or bacterial lipopolysaccharide. | hd11, a transformed avian macrophage cell line, and chicken peripheral blood leukocyte-derived macrophages (pbl-m phi) were stimulated with bacterial endotoxin lipopolysaccharide (lps) or eimeria tenella sporozoites and merozoites. the specific cytotoxicities of the culture supernatants against different target cell lines were measured, and the kinetics of tumor necrosis-like factor (tnf) production by hd11 and pbl-m phi were also measured. the results showed that hd11 and pbl-m phi secreted a t ... | 1995 | 7479508 |
| molecular characterisation of peanut agglutinin-binding glycoproteins from eimeria tenella. | a group of glycoproteins, which strongly bind peanut agglutinin (pna) was found in eimeria tenella. two major antigenic glycoproteins, et110gp and et35gp, were identified in sporulated oocysts and sporozoites. molecular characterisation of carbohydrate moieties (lectin binding, enzymic hydrolysis and monosaccharide composition) revealed that both glycoproteins are rich in galactose and n-acetylgalactosamine, and appear to be sialylated. both glycoproteins were susceptible to treatment with neura ... | 1993 | 8300307 |
| high-resolution mapping of b-cell epitopes within an antigenic sequence from eimeria tenella. | overlapping hexapeptides representing part of an eimeria tenella antigenic sequence, shown to induce partial immunity to homologous challenge in chickens, were synthesized on polypropylene pins (pepskan technique; cambridge research biochemicals, cambridge, united kingdom). the binding to these hexapeptides of antibodies from chickens infected and rabbits immunized with five species of eimeria was studied, using the coated pins as the solid phase of an enzyme-linked immunoassay. antibody binding ... | 1994 | 7523292 |
| serum coloration as a criterion of the severity of experimental coccidiosis in the chicken. | serum decoloration may be used as a criterion for the severity of coccidiosis. direct measurement of serum coloration at 480 nm is easy to carry out and, with micromethods, it is not necessary to slaughter animals. with intestinal coccidia the sensitivity is high, and there is good correlation with the severity of infection and variability is small. with eimeria tenella infection the criterion is less sensitive, but may be of value for some purposes. | 1993 | 8343813 |
| response of unimmunized and sporozoite-immunized chickens to challenge with avian eimeria species: effects of intraperitoneal injection of sephadex. | unimmunized chickens, given intraperitoneal injections of sephadex at the same time that they were inoculated with oocysts of either eimeria tenella or e. acervulina, had significantly lower lesion scores at 6 days postinoculation (pi) than unimmunized chickens that were injected with saline instead of sephadex. despite the difference in lesion scores, there was little effect on weight gain, except in one experiment, in which sephadex-injected chickens gained significantly more weight than salin ... | 1994 | 7530443 |
| eimeria tenella: sporozoites rarely enter leukocytes in the cecal epithelium of the chicken (gallus domesticus). | in this study, the intraepithelial leukocytes supposedly involved in the transportation of eimeria tenella sporozoites through the cecal lamina propria were phenotypically characterized. the ceca of naive and immune chickens were examined at various times after inoculation by light microscopy and immunocytochemical techniques. the distribution of sporozoites within the villus differed markedly between both groups. from 16 hr postinoculation, significantly fewer sporozoites had reached the crypts ... | 1995 | 7628564 |
| comparison of immune responses in inbred lines of chickens to eimeria maxima and eimeria tenella. | immune responses of 4 inbred lines of chickens, that differ in resistance to eimeria maxima and e. tenella, were examined. significant differences were found in in vitro proliferation of peripheral blood lymphocytes to e. maxima sporozoite antigen, the more resistant lines c and 7(2) having higher responses than the more susceptible line 15i. these differences existed pre-infection and were enhanced following both primary and a second infection. the proportions of lymphocyte subsets in the perip ... | 1995 | 7675528 |
| common epitopes on eimeria tenella sporozoites and cecal epithelium of chickens. | eimeria tenella sporozoites invade the intestinal epithelium at a highly specific site. certain molecules that were recognized by monoclonal antibody e. ten 11m-2, which was prepared against e. tenella sporozoites, were detected on both cecal epithelium and sporozoites. we expect that these molecules are involved in attracting sporozoites towards the site of entry. | 1993 | 7691752 |
| gamma-irradiated and nonirradiated eimeria tenella sporozoites exhibit differential uracil uptake and expression of a 7- to 10-kda metabolic antigen. | eimeria tenella sporozoites were exposed in the oocyst form to either an optimum (15 krad) or a high (25 krad) dose of gamma irradiation and used to infect cultured chicken embryo fibroblasts (cef). the sporozoite-infected cef monolayer was pulsed at time of infection or 24 hr postinfection with [3h]uracil and harvested 24 hr later to measure sporozoite metabolic activity. sporozoites exposed to either 0 or 15 krad gamma irradiation incorporated similar (p > 0.05) amounts of [3h]uracil during th ... | 1995 | 7758545 |
| detection of mucosal immune responses in chickens after immunization or infection. | in order to measure mucosal antibody responses in the chicken intestine an elisa-based assay was developed that was able to detect antigen-specific antibodies in an isotype-specific way. locally produced antibodies could be detected after overnight culture at 37 degrees c. in particular the production of iga, more than igm and igg, was significantly increased by immunization of the animals with k99 pilus antigen or by infection with eimeria tenella parasites. data presented here indicate that th ... | 1993 | 8506617 |
| maternal transfer of antibodies induced by infection with eimeria maxima partially protects chickens against challenge with eimeria tenella. | infection of breeding hens with eimeria maxima induces production of eimeria-specific igg antibodies which are transferred to hatchlings via the egg yolk and confer a high degree of maternal immunity against homologous challenge and partial immunity to infection with another important species, eimeria tenella. as an example, in an experiment using hatchlings from eggs collected between days 28 and 39 after infection of the hens with 20,000 sporulated e. maxima oocysts, control chicks (challenged ... | 1994 | 7831090 |
| inhibition of the in vitro development of eimeria tenella in chick kidney cells by immune chicken splenocytes. | an in vitro microbicidal assay was used to study the immune response of chickens to eimeria tenella by measuring the effect of splenocytes from immunized chickens on intracellular development of e. tenella. splenocytes were prepared from specific-pathogen-free chickens [strain p2a(b19b19) or n2a(b21b21)], immunized one, two, or three times with non-lethal doses of e. tenella. twelve hours following infection of chick kidney cells (ckcs) with e. tenella sporozoites, splenocytes were added to infe ... | 1994 | 7832693 |
| ultrastructural observations of development of eimeria tenella in a novel established avian-derived cell line. | transmission electron microscopy was used to study the in vitro development of eimeria tenella in a novel established avian-derived cell line (designated cev-1/f7) used for antigen production in chicken immunization studies. sporozoites of e. tenella were inoculated onto cell monolayers and the cells were fixed at 24-h intervals. large numbers of intracellular sporozoites were seen at 24 h postinoculation (p.i.), and trophozoites were identified at 24-48 h p.i. immature schizonts, some with budd ... | 1994 | 7855124 |
| effect of eimeria tenella infection on salmonella enteritidis infection in chickens. | the effect of eimeria tenella infection on the salmonella enteritidis infection in chickens was investigated in three experiments. each experiment consisted of an uninfected control, birds infected with e. tenella, birds infected with s. enteritidis, and birds infected with a combination of e. tenella and s. enteritidis. a dose of 2 x 10(4) sporulated oocysts of e. tenella was given to each chicken. in experiment 1, each chicken was infected with 10(5) cfu/d of s. enteritidis for 3 consecutive d ... | 1995 | 7899197 |
| enrichment of cecal species of avian eimeria in a mixed culture by transfer of sporozoites from foreign host to natural host birds. | an effective method for the enrichment of two cecal species of the avian eimeria in mixed cultures has been developed. the method involves the transfer of sporozoites of eimeria tenella and eimeria adenoeides from their specific site of invasion in a foreign host bird to the natural host, and markedly increases the numbers of the cecal species in relation to the other species in the mixture. donor turkeys and chickens were inoculated with mixed cultures containing equal numbers of oocysts of the ... | 1995 | 8614699 |
| physiological basis of eimeria tenella-induced mortality in individual chickens. | chickens dying from eimeria tenella infection revealed four major physiological stresses before death: (1) hypothermia, (2) depletion of carbohydrate stores, (3) metabolic acidosis, and (4) renal tubule-cell dysfunction. these stresses were less pronounced in chickens surviving the infection. similar stresses could not be demonstrated in pair-feeding trials, in which uninfected chickens were fed only the amount consumed by infected chickens. prolonged starvation of uninfected chickens only sligh ... | 1981 | 7229821 |
| resistance and cross-resistance studies with narasin, a new polyether antibiotic anticoccidial drug. | the wisconsin (wis) strain and a field strain (fs-196) of eimeria tenella were propagated in the presence of 80 ppm narasin in an attempt to select for narasin resistance. comparisons of the narasin sensitivity of the selected strains (wis-nr and fs-196-nr) and of the parent strains (wis and fs-196) from which they were derived revealed no resistance development. these findings agree with the results of similar studies with the polyether antibiotic anticoccidial drugs monensin and lasalocid and ... | 1981 | 7259679 |
| investigation for the characteristic anticoccidial activity of diclazuril in battery trials. | to clarify the character of the anticoccidial activity of diclazuril a series of battery trials was conducted. diclazuril showed excellent anticoccidial activity in the infection of chickens with eimeria tenella, e. necatrix or e. acervulina at the feeding level of 0.1 ppm. when diclazuril was administered in combination with a nucleic acid precursor, uracil, uridine, orotate or orotidine, the reduction of the activity of diclazuril to the infections induced by above species was not observed. wh ... | 1996 | 8672582 |
| cytosaminomycins, new anticoccidial agents produced by streptomyces sp. ko-8119. i. taxonomy, production, isolation and physico-chemical and biological properties. | streptomyces amakusaensis ko-8119, a soil isolate, was found to produce a series of new anticoccidial compounds. four active compounds, designated as cytosaminomycins a, b, c and d, were isolated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography and preparative hplc. cytosaminomycins inhibited the growth of eimeria tenella in an in vitro assay system using primary chicken embryonic cells as a host. no schizont in the cells was observed at ... | 1994 | 8071122 |
| peptides associated with monensin resistance in sporozoites of eimeria tenella (coccidia). | resistance to monensin in the sporozoites of a laboratory strain (wis) of eimeria tenella was amplified by treating free sporozoites with increased monensin levels in vitro, followed by propagation of these treated sporozoites in chickens. the parent strain of wis and its subsequent lines developed from the treatment of monensin at 1, 5, or 25 micrograms/ml were designated as wis(0), wis(1), wis(5), or wis(25), respectively. the penetration rate of sporozoites into primary chicken kidney cell cu ... | 1994 | 8158472 |
| increasing the yield of eimeria tenella oocysts in primary chicken kidney cells. | the present study was undertaken to increase the yield of eimeria tenella oocysts in primary chicken kidney cells (pckcs) using a comparatively inexpensive cell-culture system. pckcs growing on coverslips positioned on the bottoms of individual wells in 24-well tissue-culture plates were infected with sporozoites of e. tenella. the effects of changing the culture medium (rpmi 1640), medium ph, serum type, and serum concentration in the wells were determined by counting newly produced oocysts at ... | 1996 | 8713049 |
| amplification of ionophore resistance in a field strain of eimeria tenella by treating free sporozoites with monensin in vitro. | monensin resistance in a field strain of eimeria tenella (fs139) was successfully amplified by an in vitro method. sporozoites of parent fs139, designated as fs139(0), were treated with monensin at 5 micrograms ml-1 before inoculation into chickens. oocysts developing from these drug-treated sporozoites were designated fs139(5). sporozoites of fs139(5) were then treated with a higher level of monensin (25 micrograms ml-1), which produced another line called fs139(25). sporozoites of fs139(25) re ... | 1994 | 8171823 |
| eimeria tenella or eimeria adenoeides: induction of morphological changes and increased resistance to salmonella enteritidis infection in leghorn chicks. | the effect of either low doses of the chicken coccidium, eimeria tenella (et) or high doses of the turkey coccidium, eimeria adenoeides (ea) on salmonella enteritidis (se) organ invasion, as well as histological and morphometric changes in the ceca of leghorn chicks, was investigated. in these studies, chicks were inoculated orally with either saline solution (control) or one of three doses of sporulated oocysts of either et or ea at 1 d of age. five days later, 10(4) cfu of se were administered ... | 1994 | 8177817 |
| responses of dwarf and normal chickens to feed restriction, eimeria tenella infection, and sheep red blood cell antigen. | relationships among stress responses, habituation to feed restriction, resistance to eimeria tenella, and antibody response to srbc were studied in dwarf and normal white plymouth rocks. transfer of chicks at 22 days of age from starter to developer batteries resulted in an increase within 24 h of heterophil:lymphocyte (h:l) ratios of chicks of both genotypes. restriction of feed intake from ad libitum (al) to 60% of ad libitum reduced body weight and increased size of the crop-esophagus. as mea ... | 1993 | 8234122 |
| increase of mannose residues, as salmonella typhimurium-adhering factor, on the cecal mucosa of germ-free chickens infected with eimeria tenella. | to study increase of the salmonella population in the cecum of chickens infected with eimeria tenella, quantitative changes in mannose residues on the cecal mucosa were investigated. inhibition of s typhimurium adherence to the cecum by a 2% carbohydrate (d-mannose, d-galactose, l-fucose, alpha-methyl-d-glucoside) in phosphate-buffered saline solution was examined. only d-mannose had inhibitory effects. whereas, d-galactose had somewhat enhancing effects on adherence of s typhimurium to the ceca ... | 1993 | 8239135 |
| cloning and characterization of a surface antigen of eimeria tenella merozoites and expression using a recombinant vaccinia virus. | a rabbit serum raised against eimeria tenella merozoites was used to screen a lambda gt11 cdna library made from merozoite mrna of e. tenella. the insert of the phage clone lambda mz 5-7 revealed an open reading frame consisting of 945 nucleotides, encoding a 33-kda protein. this size is consistent with the size of a protein translated in vitro from merozoite mrna and immunoprecipitated with monospecific anti-mzp 5-7 antibodies. a smaller protein of 24 kda, located on the surface of the parasite ... | 1993 | 8264722 |
| oxygen concentration and asexual development of eimeria tenella in cell cultures. | primary chicken kidney cells in flexiperm cultures were either inoculated with eimeria tenella sporozoites or incubated as noninoculated controls. oxygen concentration was reduced (10 or 15 vol% o2, 5 vol% co2) or increased (25 or 30 vol% o2, 5 vol% co2) in a triple gas incubator (heraeus b 5061 ek/o2) and retained in a co2-air incubator (20 vol% o2, 5 vol% co2) 24 hours post inoculation (hpi). mature second generation schizonts (ms2) were counted microscopically at 120 hpi and numbers were comp ... | 1993 | 8284951 |
| the ratio of the water and food consumption of chickens and its significance in the chemotherapy of coccidiosis. | an investigation was made of the relationship between the water and food consumption of healthy and sick chickens using coccidiosis as a disease model, and uninfected chickens as healthy controls, male birds of an egg-production breed and males and females of a meat-production breed were found to have simultaneously reduced water and food intakes 4 days after infection with eimeria acervulina or e. maxima, and from 4 to 6 days after infection with e. tenella. this phenomenon was associated with ... | 1996 | 8908724 |
| protective oral immunization of chickens against eimeria tenella with sporozoite surface antigens. | antigens were extracted from the surface of eimeria tenella sporozoites with a solution containing triton x 100 (1%), sodium dodecyl sulphate (0.5%) na deoxycholate (1%) and edta (1 mm). after removal of the detergents, these surface antigen preparations conferred an immunity that protected chickens against a subsequent infection (10(4) sporulated oocysts). the best results were obtained after two 250 micrograms injections of al(oh)3 adsorbed antigens (oocyst output per g caecal material on day ... | 1993 | 8291209 |
| t lymphocyte roles during eimeria acervulina and eimeria tenella infections. | this study evaluated the effects of selective depletion of t lymphocytes on eimeria infections in chickens. cell depletions were initiated in day- or week-old hyline sc strain chickens using intra-peritoneal injections of monoclonal antibodies to cd4, cd8, or t cell receptor (tcr) alpha/beta. control chickens received injections of irrelevant monoclonal antibody or phosphate buffered saline (pbs). following the establishment of cell depletion, chickens were infected orally with e. acervulina or ... | 1996 | 8941977 |
| characterization of distal lymphoid nodules in the chicken caecum. | in this report, we describe lymphoid nodules consistently found in the distal region of each chicken caecum at approximately 3 cm from the ileo-cecal junction. these structures were studied by light microscopy both in normal and eimeria tenella-infected chickens. they were observed with the naked eye in infected birds but not in normal chickens. in these latter the region of the caecal lamina propria corresponding to that in which the lymphoid aggregates were visible revealed a light infiltratio ... | 1993 | 8311264 |
| identification of a developmentally regulated sialidase in eimeria tenella that is immunologically related to the trypanosoma cruzi enzyme. | sporozoites and merozoites of three species of eimeria, e. tenella, e. maxima, and e. necatrix, that cause diarrhea in chickens worldwide, were examined for their expression of sialidase (sa) activity. the enzyme was found in three species, and the activity of merozoites was 10-20 times higher than that of sporozoites. the enzyme was resistant to degradation by proteases that are normally present in the intestine, a site inhabited by the eimeria parasites, and it was relatively resistant to heat ... | 1993 | 8358228 |
| mapping for b-cell epitopes in the gx3262 antigenic sequence derived from eimeria tenella sporulated oocysts. | polypropylene pins were impregnated with synthetic overlapping heptapeptides based on the gx3262 eimeria tenella antigenic sequence (miller et al., 1989). using these coated pins as the solid phase of an enzyme immunoassay (eia), binding of sera from chickens and rabbits infected and immunised respectively with five different species of eimeria were examined. antibody reactions to the individual heptapeptides were then analysed by a number of criteria based on the amino acid sequence including h ... | 1996 | 9017879 |
| eimeria tenella: genetic recombination of markers for precocious development and arprinocid resistance. | a mating was made between two populations of eimeria tenella possessing the complementary traits of normal development (virulence) + resistance to the anticoccidial drug arprinocid or precocious development (attenuation) + drug-sensitivity. a small number of "recombinant" oocysts was recovered. the inheritance of markers from both parents into 22 cloned lines derived from the recombinant oocysts was confirmed by analyses of restriction fragment length polymorphisms of four repetitive dna sequenc ... | 1996 | 9060177 |
| comparative development of eimeria tenella in primary chick kidney cell cultures derived from coccidia-resistant and -susceptible chickens. | a sixfold difference in resistance to coccidia (eimeria tenella) infection between a resistant and a susceptible line of auburn white leghorn chickens, derived by selective breeding, has been reported. the purpose of the following study was to determine whether the resistance or susceptibility phenomenon in the auburn lines could be manifested in a homogeneous group of isolated host kidney cells that support e. tenella development in vitro but not normally in vivo. propagation of the parasite in ... | 1993 | 8426849 |
| efficacy of semduramicin and salinomycin against different stages of eimeria tenella and e. acervulina in the chicken. | the efficacy of a new ionophore, semduramicin, was compared with salinomycin in a series of in ovo and in vivo trials. semduramicin was more efficacious than salinomycin against eimeria tenella sporozoites as judged by oocyst production in embryonated eggs. when the two drugs were given in ovo at 93 h post inoculation (pi), both drugs exerted some effect against late schizogonous stages of e. tenella. in three battery studies, semduramicin (25 ppm) and salinomycin (60 and 66 ppm) were tested aga ... | 1993 | 8447065 |
| eimeria tenella: characterization of a 5s ribosomal rna repeat unit and its use as a species-specific probe. | the oocysts of eimeria tenella, one of the most pathogenic of several species causing chicken coccidiosis, are difficult to distinguish microscopically from several other infective eimeria species. one copy of a gene coding for 5s ribosomal rna has been cloned from e. tenella and sequenced. a coding region of 120 nucleotides and an intergenic region of 608 nucleotides together make up a 5s rrna repeat unit, of which there are many copies tandemly repeated in the genome. the intergenic region is ... | 1993 | 8467900 |
| secretion of an eimeria tenella sporozoite antigen during host-cell invasion: visualization of the parasitophorous vacuole membrane and parasitophorous duct-like structures. | | 1993 | 8469674 |
| potentiation of ionophorous anticoccidials with dihydroquinolines: compatibility of lasalocid and semduramicin with duokvin. | three battery tests were conducted to reveal whether or not there is an interaction between the new dihydroquinoline antioxidant, duokvin and lasalocid or the new anticoccidial, semduramicin, similar to that observed with some other ionophorous anticoccidials. in terms of body weight gain, no significant difference due to toxic interaction between duokvin and any dose of lasalocid or semduramicin was detected in chickens experimentally infected with oocysts of eimeria tenella and e. mitis. antic ... | 1995 | 8557471 |
| effect of lactose and lactobacillus acidophilus on the colonization of salmonella enteritidis in chicks concurrently infected with eimeria tenella. | the effect of dietary lactose and lactobacillus acidophilus on the colonization of salmonella enteritidis (phage type 4) in newly hatched leghorn chicks concurrently infected with eimeria tenella was studied. there were six groups of birds in each of two replicate trials: uninfected controls, birds infected with s. enteritidis, birds infected with s. enteritidis and e. tenella, birds infected with s. enteritidis and e. tenella that were fed with dietary lactose (5%), birds infected with s. enter ... | 1995 | 8561740 |
| characterization and immunoprotective properties of a monoclonal antibody against the major oocyst wall protein of eimeria tenella. | the oocyst wall of eimeria spp. consists of a 10-nm-thick outer lipid layer and a 90-mm-thick inner layer of glycoprotein which has been described previously to be composed of a single major protein. sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions and (125)i labelling of a oocyst wall fragments and of delipidated intact oocysts revealed a molecule of approximately 12 kda as the major protein component of the oocyst wall of eimeria tenella. an immunoglobulin m ... | 1996 | 8606083 |
| effects of supplemental ascorbic acid on the performance of broiler chickens exposed to multiple concurrent stressors. | an experiment was conducted to determine whether ascorbic acid (aa) increases resistance of female hubbard x hubbard broiler chicks to multiple concurrent stressors. stressors imposed from 10 to 17 d posthatch included 2 x 2 x 2 factorial combinations of beak trimming [(b), sham-operated or beak-trimmed and cauterized], coccidiosis [(c), gavage with 0 or 3 x 10(5) sporulated eimeria tenella oocysts], and heat stress [(h), 28 vs 33 c]. a starter diet was supplemented with aa to provide 0, 150, or ... | 1995 | 8614686 |
| eimeria tenella infection induces recrudescence of previous salmonella enteritidis infection in chickens. | four experiments were conducted to examine the effect of eimeria tenella infection on the recrudescence of salmonella enteritidis in previously infected chickens. significant recrudescence of cecal colonization in the birds challenged with e. tenella was observed at 3 wk after s. enteritidis infection in experiment 1, at 3 and 4 wk in experiment 2, and at 3, 4, and 5 wk in experiments 3 and 4. the recrudescence was indicated by .81 to 6.31 logs increase in cecal s. enteritidis counts and by high ... | 1995 | 8614687 |
| eimeria tenella: role of carbohydrates on sporozoite at the penetration into cultured cells. | the effects of carbohydrates on the penetration of eimeria tenella sporozoites into cultured cells were investigated. eight different carbohydrates that have been known to be on the surfaces of animal cells were added to culture medium during the penetration period. d-galactose alone inhibited sporozoite penetration into primary chicken kidney cells. when kidney cells were pretreated with d-galactose and infected with e. tenella sporozoites, the penetration was suppressed significantly, but not ... | 1996 | 8654553 |
| antagonistic effect of nucleic acid precursors on the anticoccidial activity of 6-azauracil. | the antagonistic phenomena to anticoccidial activities of 6-azauracil (azu) induced by certain nucleic acid precursors were examined in battery experiments. each nucleic acid precursor, orotate, orotidine, uracil, uridine, adenine and adenosine was mixed in feed in combination with effective levels of azu. the test feed was provided through the test term to white leghorn cockerels which were infected with eimeria tenella, e. necatrix or e. acervulina. in vitro tests were also conducted for antag ... | 1996 | 8672581 |
| assessment of recombinant bovine somatotropin as an immunomodulator during avian coccidiosis: immunization with living oocysts. | coccidiosis, a disease of great economic importance to the poultry industry, is generally controlled prophylactically by additions of anticoccidial drugs to the feed. however, increasing development of drug-resistant coccidia species has stimulated searches for alternative control methods, one of which is vaccination. as part of this effort, recombinant bovine growth hormone (rbst) was tested as a possible immune stimulator in combination with live oocyst vaccination. at a dose of 0.045 mg per c ... | 1997 | 9251145 |
| purification and characterisation of a serine-type protease from eimeria tenella oocysts. | homogenates of sporulated oocysts of e. tenella have detectable proteolytic activity which is completely inhibited by phenylmethylsulfonyl fluoride and l-trans-epoxysuccinyl-leucyl-amido-(4-guanidino)-butane, indicating the presence of both serine and cysteine-type proteases in sporulated oocysts. a serine-type protease has been purified from the homogenate using immobilised-bacitracin affinity chromatography. the monomeric enzyme had an apparent m(r) of 20,000 and a pi of 8.6. the maximum prote ... | 1994 | 8026895 |
| effects of components of artemisia annua on coccidia infections in chickens. | four experiments were run to test the anticoccidial activity of dried artemisia annua leaves and several of their chemical constituents for possible use as prophylactic feed additives. when fed over a period of 3 wk at a level of 5%, a dried leaf supplement of a. annua provided significant protection against lesions due to eimeria tenella but not eimeria acervulina or eimeria maxima. when fed over a period of 5 wk at a level of 1% to chicks undergoing immunization with a live vaccine, it provide ... | 1997 | 9251146 |
| evaluation of plasma chemistry and haematological studies on chickens infected with eimeria tenella and e acervulina. | plasma chemistry and haematological studies were conducted on chickens with coccidiosis. male white leghorn chickens, of two weeks old, were inoculated with 5 x 10(4) eimeria tenella sporulated oocysts or with 1 x 10(6) e acervulina sporulated oocysts. blood samples were taken four, seven and 11 days after inoculation. a wet chemistry system was applied to measure the plasma activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma glutamyltransferase, creat ... | 1997 | 9253831 |
| kinetics of specific immunoglobulin a, m and g production in the duodenal and caecal mucosa of chickens infected with eimeria acervulina or eimeria tenella. | the development and appearance of antibody was studied in the intestine and serum from histocompatible gb1 chickens orally infected with oocysts of eimeria acervulina (restricted to the duodenum) or eimeria tenella (restricted to the caeca). the local immune response was measured as the specific antibody levels in the supernatants of intestinal fragments (duodenum and caecum) maintained in culture for 16 h at 41 degrees c, 5% co2, 95% air. specific igm was detected 1 week after e. acervulina inf ... | 1997 | 9279583 |
| use of igg- and igm-specific elisas for the assessment of exposure status of chickens to eimeria species. | simple and reliable methods for the determination of the exposure status of chickens to eimeria species are required. for this purpose an enzyme-linked immunosorbent assay (elisa) detecting specific igg and igm antibodies in serum samples was evaluated. sera from chickens hyperimmunized by intramuscular injection of a saline extract of eimeria tenella sporozoites were used to determine optimal reaction conditions in the elisa which were found to be at a serum dilution of 1:100 and an antigen con ... | 1993 | 8128576 |
| susceptibility to eimeria tenella of chickens and chicken embryos of partly inbred lines possessing homozygous major histocompatibility complex haplotypes. | susceptibility to eimeria tenella infection of chicken embryos and chickens of partly inbred lines possessing different major histocompatibility complex haplotypes was investigated. chicken embryos of line h-b2 possessing b2 homozygous haplotype showed lower mortality and higher oocyst production than embryos of line h-b15 possessing b15 homozygous haplotype. embryos of line h-b2 chickens were considered more resistant to e. tenella infection than those of line h-b15. seven days after 10-day-old ... | 1993 | 8141741 |
| eimeria tenella: infection with a single sporocyst gives a clonal population. | two genetically defined parents of eimeria tenella, each characterized by a selectable phenotype, were mated to provide "recombinant' oocysts for an analysis of the inheritance of dna markers into the sporocyst stage of the life-cycle. a total of 23 populations was established from infection with a putative single sporocyst and their inheritance of dna markers provided compelling evidence that the 2 sporozoites within each sporocyst are genetically identical. each of the 5 polymorphic dna marker ... | 1996 | 8684826 |
| immunity to eimeria tenella in chickens: phenotypical and functional changes in peripheral blood t-cell subsets. | the changes in peripheral blood leukocyte (pbl) t-cell subsets following eimeria tenella infection in outbred white leghorn chickens were studied, using a panel of murine monoclonal antibodies specific for the chicken homologues of the mammalian cd3, cd8, and cd4 markers on day-to-day samples of pbls. both flow cytometric analysis (fca) and immunofluorescence microscopy with fixed cells on slides were used as read-out systems. the changes in the composition of the t-cell subsets measured with bo ... | 1996 | 8713046 |
| eimeria tenella and e. acervulina: differences in ability to elicit cross-species protection as compared with the turkey coccidium, e. adenoeides. | repeated oral inoculation of turkey poults with large doses (1 x 10(6) oocysts) of the chicken coccidia, eimeria tenella or e. acervulina, failed to prevent weight loss, poor feed conversion, and intestinal pathology in turkeys challenged with the turkey coccidium, e. adenoeides. invasion by e. tenella in turkeys was significantly greater than invasion by e. adenoeides in chickens; by 24 hr postinoculation (pi), the numbers of e. tenella and e. adenoeides sporozoites in the ceca had decreased ma ... | 1995 | 8719203 |
| in vivo role of tumor necrosis-like factor in eimeria tenella infection. | the effect of tumor necrosis-like factor (tnlf) on the pathogenesis of coccidiosis was investigated. injection of crude chicken tnlf enhanced the weight loss caused by eimeria tenella infection. rabbit polyclonal antibody against recombinant human tumor necrosis factor-alpha (rhtnf) partially restored e. tenella-induced weight loss in sc chickens, but not in tk chickens. however, injection of chickens with chicken tnlf, rhtnf, and rabbit serum against rhtnf had no significant effect on cecal les ... | 1995 | 8719221 |
| effect of eimeria tenella infection on the production of salmonella enteritidis-contaminated eggs and susceptibility of laying hens to s. enteritidis infection. | experiments were conducted to determine the effect of eimeria tenella infection on the production of salmonella enteritidis-contaminated eggs and susceptibility of egg-laying hens to s. enteritidis infection. the dose of sporulated oocysts of e. tenella used in the present study was 2 x 10(5) per chicken. when hens were infected with 10(6) colony-forming units (cfu) of s. enteritidis, e. tenella infection resulted in a significant increase (p < 0.05) of s. enteritidis contamination in the shells ... | 1996 | 8790887 |
| association of lowered plasma carotenoids with protection against cecal coccidiosis by diets high in n-3 fatty acids. | a series of four experiments was run to assess the effectiveness of diets containing high amounts of n-3 fatty acids in reducing the pathological effects of cecal coccidiosis in chickens caused by eimeria tenella. to determine whether the dietary effects were related to development of oxidative stress, plasma samples were analyzed for tocopherols and carotenoids. plasma vitamin e (alpha-tocopherol) values were not consistent between experiments. total plasma carotenoids, however, were significan ... | 1996 | 8829228 |
| diets high in n-3 fatty acids reduce cecal lesion scores in chickens infected with eimeria tenella. | four experiments were run in which diets incorporating various levels of n-3 fatty acids (n-3fa) from fish (menhaden) oil or flax seed were tested for their abilities to reduce the severity of eimeria tenella infections in young broiler chicks. the diets were fed from 1 d of age through 3 wk of age. chickens were infected at 2 wk of age. diets consisting of broiler starter ration supplemented with 2.5 to 10% fish oil, 10% flax seed oil, or 10% linseed oil significantly decreased cecal lesions an ... | 1996 | 8833367 |
| the effect of bcg, zymosan and coxiella burnetti extract on eimeria infections. | infection of animals with species of eimeria induces a hyper-reactivity to endotoxin as manifest by a greatly increased capacity of infected animals to produce tnf in response to lps in vivo compared with uninfected animals. this finding indicates priming for hyperactivation of macrophages by eimeria infection and raises the possibility that non-specific triggering of macrophages by agents such as bacille calmette-guerin (bcg), zymosan or coxiella burnetti extract may be a simple means of contro ... | 1996 | 8872185 |
| identification of a fibronectin-like molecule on eimeria tenella. | the attachment of eimeria tenella to its target cells as an obligatory intracellular pathogen is essential for the development of disease. previous reports have established that other intracellular protozoa parasites have either fibronectin, an adhesion protein, or fibronectin receptors, both of which are involved in the interaction with the host cells. in this current research, studies have been undertaken to visualize a surface component that may be involved in the attachment of e. tenella to ... | 1996 | 8939046 |
| eimeria tenella infections in chickens: aspects of host-parasite: interaction. | intestinal coccidiosis, caused by various species of eimeria, has become an economically important disease of poultry and livestock throughout the world. infection of chickens starts after ingestion of oocysts when sporozoites penetrate the epithelium of the villi. after passage through the lamina propria, they enter crypt epithelial cells where they undergo several rounds of asexual and sexual proliferation, thus forming merozoites and later, gametocytes. when macrogametes are fertilized by mic ... | 1996 | 8988869 |
| [the t and b immunity systems in eimeriosis (eimeria tenella) in domestic chickens]. | it has been shown that the three fold immunisation of 30 day old chicken with 10, 50 and 100 thousand oocysts of e. tenella at intervals 15 day induces increasing amounts of t- and b-lymphocytes in thymus, spleen and bursa of fabricius. the mode of lymphocyte dynamics at immunization is considered in terms of host-parasite relationships, possible ways of anti-eimerian immunity formation being discussed. | 1996 | 8999415 |