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Gurbuz Das - One of the best experts on this subject based on the ideXlab platform.
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excretion of histomonas meleagridis following experimental co infection of distinct chicken lines with Heterakis Gallinarum and ascaridia galli
Parasites & Vectors, 2021Co-Authors: Gurbuz Das, Manuel Stehr, Cornelia C. Metges, Lukas Wachter, Ivana Bilic, Beatrice Grafl, Patricia Wernsdorf, Michael Hess, Dieter LiebhartAbstract:BACKGROUND Histomonosis is a severe re-emerging disease of poultry caused by Histomonas meleagridis, a protozoan parasite which survives in the environment via the cecal worm Heterakis Gallinarum. Following infection, the parasites reside in the ceca and are excreted via host feces. In the present work, male birds of conventional broiler (Ross 308, R), layer (Lohmann Brown Plus, LB) and a dual-purpose (Lohmann Dual, LD) chicken line were infected with 250 embryonated eggs of Ascaridia galli and Heterakis Gallinarum, respectively, with the latter nematode harboring Histomonas meleagridis, to investigate a co-infection of nematodes with the protozoan parasite in different host lines. METHODS In weekly intervals, from 2 to 9 weeks post infection (wpi), individual fecal samples (n = 234) from the chickens were collected to quantify the excretion of H. meleagridis by real-time PCR and to determine the number of nematode eggs per gram (EPG) in order to elucidate excretion dynamics of the flagellate and the nematodes. This was further investigated by indirect detection using plasma samples of the birds to detect antibodies specific for H. meleagridis and worms by ELISA. The infection with H. meleagridis was confirmed by histopathology and immunohistochemistry to detect the flagellate in the cecum of representing birds. RESULTS The excretion of H. meleagridis could already be observed from the 2nd wpi in some birds and increased to 100% in the last week of the experiment in all groups independent of the genetic line. This increase could be confirmed by ELISA, even though the number of excreted H. meleagridis per bird was generally low. Overall, histomonads were detected in 60% to 78% of birds with temporary differences between the different genetic lines, which also showed variations in the EPG and worm burden of both nematodes. CONCLUSIONS The infection with H. Gallinarum eggs contaminated with H. meleagridis led to a permanent excretion of the flagellate in host feces. Differences in the excretion of H. meleagridis in the feces of genetically different host lines occurred intermittently. The excretion of the protozoan or its vector H. Gallinarum was mostly exclusive, showing a negative interaction between the two parasites in the same host.
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excretion of histomonas meleagridis following experimental co infection of distinct chicken lines with Heterakis Gallinarum and ascaridia galli
Parasites & Vectors, 2021Co-Authors: Gurbuz Das, Manuel Stehr, Cornelia C. Metges, Lukas Wachter, Ivana Bilic, Beatrice Grafl, Patricia Wernsdorf, Michael Hess, Dieter LiebhartAbstract:Histomonosis is a severe re-emerging disease of poultry caused by Histomonas meleagridis, a protozoan parasite which survives in the environment via the cecal worm Heterakis Gallinarum. Following infection, the parasites reside in the ceca and are excreted via host feces. In the present work, male birds of conventional broiler (Ross 308, R), layer (Lohmann Brown Plus, LB) and a dual-purpose (Lohmann Dual, LD) chicken line were infected with 250 embryonated eggs of Ascaridia galli and Heterakis Gallinarum, respectively, with the latter nematode harboring Histomonas meleagridis, to investigate a co-infection of nematodes with the protozoan parasite in different host lines. In weekly intervals, from 2 to 9 weeks post infection (wpi), individual fecal samples (n = 234) from the chickens were collected to quantify the excretion of H. meleagridis by real-time PCR and to determine the number of nematode eggs per gram (EPG) in order to elucidate excretion dynamics of the flagellate and the nematodes. This was further investigated by indirect detection using plasma samples of the birds to detect antibodies specific for H. meleagridis and worms by ELISA. The infection with H. meleagridis was confirmed by histopathology and immunohistochemistry to detect the flagellate in the cecum of representing birds. The excretion of H. meleagridis could already be observed from the 2nd wpi in some birds and increased to 100% in the last week of the experiment in all groups independent of the genetic line. This increase could be confirmed by ELISA, even though the number of excreted H. meleagridis per bird was generally low. Overall, histomonads were detected in 60% to 78% of birds with temporary differences between the different genetic lines, which also showed variations in the EPG and worm burden of both nematodes. The infection with H. Gallinarum eggs contaminated with H. meleagridis led to a permanent excretion of the flagellate in host feces. Differences in the excretion of H. meleagridis in the feces of genetically different host lines occurred intermittently. The excretion of the protozoan or its vector H. Gallinarum was mostly exclusive, showing a negative interaction between the two parasites in the same host.
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diurnal variation in egg excretion by Heterakis Gallinarum
Parasitology, 2019Co-Authors: Gurbuz Das, Pal O Westermark, Matthias GaulyAbstract:Periodicity in nematode egg excretion may be of evolutionary origin as it can favour dispersal of the eggs in the environment. We investigated whether egg excretion by Heterakis Gallinarum shows a repeatable pattern of periodicity. The faecal egg concentration and total number of eggs excreted within 4-h intervals were significantly affected by the sampling time within 1 day, but remained unaffected by the sampling day or interaction effects. By contrast, the total number of eggs excreted within 24 h did not differ among the 4 days of the study, collectively indicating repeatable egg excretion patterns. Both host feces and parasite egg excretion increased from night to late afternoon, followed by a decrease in the evening, resulting in higher egg excretion during daytime than the dark period. Feces excretion and worm fecundity showed overlapping diurnal rhythms with similarly timed phases, suggesting the existence of synchronicity between the host feces and nematode egg excretion patterns. We conclude that egg excretion by H. Gallinarum is synchronized with host feces excretion and is higher during the daytime than during the dark period. This overlaps with the maximum activity of the day-active host and allows a maximal dispersal of the eggs in the environment.
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Co-expulsion of Ascaridia galli and Heterakis Gallinarum by chickens.
International journal for parasitology, 2018Co-Authors: Manuel Stehr, Matthias Gauly, Q. Sciascia, Cornelia C. Metges, Gurbuz DasAbstract:Abstract Worm expulsion is known to occur in mammalian hosts exposed to mono-species helminth infections, whilst this phenomenon is poorly described in avian hosts. Mono-species infections, however, are rather rare under natural circumstances. Therefore, we quantified the extent and duration of worm expulsion by chickens experimentally infected with both Ascaridia galli and Heterakis Gallinarum, and investigated the accompanying humoral and cell-mediated host immune responses in association with population dynamics of the worms. Results demonstrated the strong co-expulsion of the two ascarid species in three phases. The expulsion patterns were characterized by non-linear alterations separated by species-specific time thresholds. Ascaridia galli burden decreased at a daily expulsion rate (e) of 4.3 worms up to a threshold of 30.5 days p.i., followed by a much lower second expulsion rate (e = 0.46), which resulted in almost, but not entirely, complete expulsion. Heterakis Gallinarum was able to induce reinfection within the experimental period (9 weeks). First generation H. Gallinarum worms were expelled at a daily rate of e = 0.8 worms until 36.4 days p.i., and thereafter almost no expulsion occurred. Data on both humoral and tissue-specific cellular immune responses collectively indicated that antibody production in chickens with multispecies ascarid infections is triggered by Th2 polarisation. Local Th2 immune responses and mucin-regulating genes are associated with the regulation of worm expulsion. In conclusion, the chicken host is able to eliminate the vast majority of both A. galli and H. Gallinarum in three distinct phases. Worm expulsion was strongly associated with the developmental stages of the worms, where the elimination of juvenile stages was specifically targeted. A very small percentage of worms was nevertheless able to survive, reach maturity and induce reinfection if given sufficient time to complete their life cycle. Both humoral and local immune responses were associated with worm expulsion.
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egg production dynamics and fecundity of Heterakis Gallinarum residing in different caecal environments of chickens induced by fibre rich diets
Veterinary Parasitology, 2014Co-Authors: Gurbuz Das, Hansjorg Abel, Turker Savas, Birgit Sohnrey, Matthias GaulyAbstract:In modern husbandry systems, feed rations for laying hens may contain high levels of dietary fibre, which may only be fermented intestinally. Depending on fermentation properties, the type of dietary fibre may influence the intra-caecal environment constituting the predilection site of Heterakis Gallinarum. We investigated egg production dynamics and fecundity of H. Gallinarum residing in different caecal environments induced through different types of dietary fibre. Growing layers were fed a standard (CON) or an insoluble- (I-) or soluble- (S-) non-starch polysaccharides-(NSP) supplemented diet for the first 11 weeks (wk) of life in a twice-replicated experiment. At 3 wk of age, the birds were infected with 200 embryonated eggs of H. Gallinarum. Starting from 3 wk post-infection (p.i.), individual daily total excreta were collected. The number of eggs per gram of faeces (EPG) was determined (N = 2240), and the number of eggs per day (EPD) were estimated. The birds were necropsied 8 wk p.i. and the worm burdens were quantified. The nematode began to lay eggs as early as 23 d.p.i. and thereafter laid on average 436 eggs/d. I-NSP- and S-SNP-supplemented diets expedited the onset of patency by approximately 5 days, and increased total egg excretion by 110% and 185%, respectively, due to higher worm counts. The latter diet (S-SNP) additionally increased total egg excretion by 94% due to enhanced fecundity. Longitudinally collected data showed that fecundity of the nematode (EPD/female) was relatively stable starting from the second week of the patent phase. Results suggest that NSP-induced enlargement of caeca favoured establishment of the nematode while effects of an intensified microbial fermentation through S-NSP were crucial for an enhancement in the worm fecundity. Based on the long-term data obtained from daily collections of total excreta in experimentally H. Gallinarum-infected chickens, it is concluded that a diet enriched with pea bran as source of insoluble NSP increased worm egg production merely through elevated worm counts, whereas a diet supplemented with chicory root meal as source of soluble NSP elevated worm egg production through both increased worm counts, and more profoundly through enhanced fecundity.
Matthias Gauly - One of the best experts on this subject based on the ideXlab platform.
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diurnal variation in egg excretion by Heterakis Gallinarum
Parasitology, 2019Co-Authors: Gurbuz Das, Pal O Westermark, Matthias GaulyAbstract:Periodicity in nematode egg excretion may be of evolutionary origin as it can favour dispersal of the eggs in the environment. We investigated whether egg excretion by Heterakis Gallinarum shows a repeatable pattern of periodicity. The faecal egg concentration and total number of eggs excreted within 4-h intervals were significantly affected by the sampling time within 1 day, but remained unaffected by the sampling day or interaction effects. By contrast, the total number of eggs excreted within 24 h did not differ among the 4 days of the study, collectively indicating repeatable egg excretion patterns. Both host feces and parasite egg excretion increased from night to late afternoon, followed by a decrease in the evening, resulting in higher egg excretion during daytime than the dark period. Feces excretion and worm fecundity showed overlapping diurnal rhythms with similarly timed phases, suggesting the existence of synchronicity between the host feces and nematode egg excretion patterns. We conclude that egg excretion by H. Gallinarum is synchronized with host feces excretion and is higher during the daytime than during the dark period. This overlaps with the maximum activity of the day-active host and allows a maximal dispersal of the eggs in the environment.
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Co-expulsion of Ascaridia galli and Heterakis Gallinarum by chickens.
International journal for parasitology, 2018Co-Authors: Manuel Stehr, Matthias Gauly, Q. Sciascia, Cornelia C. Metges, Gurbuz DasAbstract:Abstract Worm expulsion is known to occur in mammalian hosts exposed to mono-species helminth infections, whilst this phenomenon is poorly described in avian hosts. Mono-species infections, however, are rather rare under natural circumstances. Therefore, we quantified the extent and duration of worm expulsion by chickens experimentally infected with both Ascaridia galli and Heterakis Gallinarum, and investigated the accompanying humoral and cell-mediated host immune responses in association with population dynamics of the worms. Results demonstrated the strong co-expulsion of the two ascarid species in three phases. The expulsion patterns were characterized by non-linear alterations separated by species-specific time thresholds. Ascaridia galli burden decreased at a daily expulsion rate (e) of 4.3 worms up to a threshold of 30.5 days p.i., followed by a much lower second expulsion rate (e = 0.46), which resulted in almost, but not entirely, complete expulsion. Heterakis Gallinarum was able to induce reinfection within the experimental period (9 weeks). First generation H. Gallinarum worms were expelled at a daily rate of e = 0.8 worms until 36.4 days p.i., and thereafter almost no expulsion occurred. Data on both humoral and tissue-specific cellular immune responses collectively indicated that antibody production in chickens with multispecies ascarid infections is triggered by Th2 polarisation. Local Th2 immune responses and mucin-regulating genes are associated with the regulation of worm expulsion. In conclusion, the chicken host is able to eliminate the vast majority of both A. galli and H. Gallinarum in three distinct phases. Worm expulsion was strongly associated with the developmental stages of the worms, where the elimination of juvenile stages was specifically targeted. A very small percentage of worms was nevertheless able to survive, reach maturity and induce reinfection if given sufficient time to complete their life cycle. Both humoral and local immune responses were associated with worm expulsion.
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egg production dynamics and fecundity of Heterakis Gallinarum residing in different caecal environments of chickens induced by fibre rich diets
Veterinary Parasitology, 2014Co-Authors: Gurbuz Das, Hansjorg Abel, Turker Savas, Birgit Sohnrey, Matthias GaulyAbstract:In modern husbandry systems, feed rations for laying hens may contain high levels of dietary fibre, which may only be fermented intestinally. Depending on fermentation properties, the type of dietary fibre may influence the intra-caecal environment constituting the predilection site of Heterakis Gallinarum. We investigated egg production dynamics and fecundity of H. Gallinarum residing in different caecal environments induced through different types of dietary fibre. Growing layers were fed a standard (CON) or an insoluble- (I-) or soluble- (S-) non-starch polysaccharides-(NSP) supplemented diet for the first 11 weeks (wk) of life in a twice-replicated experiment. At 3 wk of age, the birds were infected with 200 embryonated eggs of H. Gallinarum. Starting from 3 wk post-infection (p.i.), individual daily total excreta were collected. The number of eggs per gram of faeces (EPG) was determined (N = 2240), and the number of eggs per day (EPD) were estimated. The birds were necropsied 8 wk p.i. and the worm burdens were quantified. The nematode began to lay eggs as early as 23 d.p.i. and thereafter laid on average 436 eggs/d. I-NSP- and S-SNP-supplemented diets expedited the onset of patency by approximately 5 days, and increased total egg excretion by 110% and 185%, respectively, due to higher worm counts. The latter diet (S-SNP) additionally increased total egg excretion by 94% due to enhanced fecundity. Longitudinally collected data showed that fecundity of the nematode (EPD/female) was relatively stable starting from the second week of the patent phase. Results suggest that NSP-induced enlargement of caeca favoured establishment of the nematode while effects of an intensified microbial fermentation through S-NSP were crucial for an enhancement in the worm fecundity. Based on the long-term data obtained from daily collections of total excreta in experimentally H. Gallinarum-infected chickens, it is concluded that a diet enriched with pea bran as source of insoluble NSP increased worm egg production merely through elevated worm counts, whereas a diet supplemented with chicory root meal as source of soluble NSP elevated worm egg production through both increased worm counts, and more profoundly through enhanced fecundity.
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density related effects on lifetime fecundity of Heterakis Gallinarum in chickens
Parasites & Vectors, 2014Co-Authors: Gurbuz Das, Matthias GaulyAbstract:Background Density related effects, both inverse density- and density-dependent, contribute to regulating population dynamics of parasites. We investigated whether density related effects are directly controlling lifetime fecundity of Heterakis Gallinarum.
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precision repeatability and representative ability of faecal egg counts in Heterakis Gallinarum infected chickens
Veterinary Parasitology, 2011Co-Authors: Gurbuz Das, Hansjorg Abel, Turker Savas, Falko Kaufmann, Ahmad Idris, Matthias GaulyAbstract:This study investigated whether a precise and repeatable quantification of Heterakis Gallinarum egg excretion, which considerably reflects the actual worm burdens, can be achieved based on collection of the daily total amount of faeces from chickens. Three-week-old birds (N=64) were infected with 200 embryonated eggs of H. Gallinarum, and placed into individual cages 3 wk after infection for 5 wk to collect daily faeces (N=2240). The total daily faeces was mixed and a randomly taken sample per bird was analyzed to estimate the numbers of eggs per gram of faeces (EPG) and total number of eggs excreted within 24h (EPD). A total of 235 daily faecal collections were randomly selected and further examined to determine between and within sample variations of EPG counts as a measure of precision. For this, two random faecal samples were taken from the daily produced faeces by a bird, and the EPG was determined for each of the samples (EPG1 and EPG2). The second faecal sample was analyzed once more to determine a parallel EPG2 count (EPG2a) of the suspended sample. Precision of an EPG count was defined as its relative closeness to the average of two EPG counts using a relative asymmetry index (Index(EPG)). At an age of 11 wk, i.e. 8 wk p.i. the birds were slaughtered and their worm burdens were determined. There were no significant differences between EPG1 and EPG2 (P=0.764) nor between EPG2 and EPG2a (P=0.700), suggesting that the differences between or within the samples were not different from zero. Correlations between EPG counts, as between and within sample coherences, were r=0.85 and r=0.86, respectively. Precision of EPG counts, as measured by Index(EPG), was not influenced by consistency (P=0.870) and total amount of faeces (P=0.088). However, concentration of eggs in faeces (mean EPG) had a significant effect on the precision of the EPG counts (P<0.001). Similar results were also observed for the within sample precision (Index(EPG2)). A segmented regression analysis indicated an abrupt change in the precision of EPG counts as the response to changing egg concentration in the examined faecal samples. The precision of analyses remarkably heightened up to a breakpoint with an EPG count of ≤ 617. A similar breakpoint was also determined for within sample precision (EPG2 ≤ 621). Moderate repeatabilities (R=0.49) for EPG and EPD were estimated in the first week of egg excretion, whereas the estimates were higher (R=0.67-0.84) in the following weeks. Correlations between number of female worms with daily measured EPG and EPD increased to an almost constant level (r ≥ 0.70; P<0.05) in a few days after the nematode excreted eggs and predominantly remained so for the rest of the sampling period. It is concluded that mixing daily total faeces provides samples with random homogenous distribution of H. Gallinarum eggs. Precision of the EPG counts increases as the egg concentration in faecal sample increases. Egg excretion of H. Gallinarum, quantified either as EPG or EPD, is highly repeatable and closely correlated with the actual worm burden of birds starting as early as in 5 th wk of infection.
Dieter Liebhart - One of the best experts on this subject based on the ideXlab platform.
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excretion of histomonas meleagridis following experimental co infection of distinct chicken lines with Heterakis Gallinarum and ascaridia galli
Parasites & Vectors, 2021Co-Authors: Gurbuz Das, Manuel Stehr, Cornelia C. Metges, Lukas Wachter, Ivana Bilic, Beatrice Grafl, Patricia Wernsdorf, Michael Hess, Dieter LiebhartAbstract:BACKGROUND Histomonosis is a severe re-emerging disease of poultry caused by Histomonas meleagridis, a protozoan parasite which survives in the environment via the cecal worm Heterakis Gallinarum. Following infection, the parasites reside in the ceca and are excreted via host feces. In the present work, male birds of conventional broiler (Ross 308, R), layer (Lohmann Brown Plus, LB) and a dual-purpose (Lohmann Dual, LD) chicken line were infected with 250 embryonated eggs of Ascaridia galli and Heterakis Gallinarum, respectively, with the latter nematode harboring Histomonas meleagridis, to investigate a co-infection of nematodes with the protozoan parasite in different host lines. METHODS In weekly intervals, from 2 to 9 weeks post infection (wpi), individual fecal samples (n = 234) from the chickens were collected to quantify the excretion of H. meleagridis by real-time PCR and to determine the number of nematode eggs per gram (EPG) in order to elucidate excretion dynamics of the flagellate and the nematodes. This was further investigated by indirect detection using plasma samples of the birds to detect antibodies specific for H. meleagridis and worms by ELISA. The infection with H. meleagridis was confirmed by histopathology and immunohistochemistry to detect the flagellate in the cecum of representing birds. RESULTS The excretion of H. meleagridis could already be observed from the 2nd wpi in some birds and increased to 100% in the last week of the experiment in all groups independent of the genetic line. This increase could be confirmed by ELISA, even though the number of excreted H. meleagridis per bird was generally low. Overall, histomonads were detected in 60% to 78% of birds with temporary differences between the different genetic lines, which also showed variations in the EPG and worm burden of both nematodes. CONCLUSIONS The infection with H. Gallinarum eggs contaminated with H. meleagridis led to a permanent excretion of the flagellate in host feces. Differences in the excretion of H. meleagridis in the feces of genetically different host lines occurred intermittently. The excretion of the protozoan or its vector H. Gallinarum was mostly exclusive, showing a negative interaction between the two parasites in the same host.
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excretion of histomonas meleagridis following experimental co infection of distinct chicken lines with Heterakis Gallinarum and ascaridia galli
Parasites & Vectors, 2021Co-Authors: Gurbuz Das, Manuel Stehr, Cornelia C. Metges, Lukas Wachter, Ivana Bilic, Beatrice Grafl, Patricia Wernsdorf, Michael Hess, Dieter LiebhartAbstract:Histomonosis is a severe re-emerging disease of poultry caused by Histomonas meleagridis, a protozoan parasite which survives in the environment via the cecal worm Heterakis Gallinarum. Following infection, the parasites reside in the ceca and are excreted via host feces. In the present work, male birds of conventional broiler (Ross 308, R), layer (Lohmann Brown Plus, LB) and a dual-purpose (Lohmann Dual, LD) chicken line were infected with 250 embryonated eggs of Ascaridia galli and Heterakis Gallinarum, respectively, with the latter nematode harboring Histomonas meleagridis, to investigate a co-infection of nematodes with the protozoan parasite in different host lines. In weekly intervals, from 2 to 9 weeks post infection (wpi), individual fecal samples (n = 234) from the chickens were collected to quantify the excretion of H. meleagridis by real-time PCR and to determine the number of nematode eggs per gram (EPG) in order to elucidate excretion dynamics of the flagellate and the nematodes. This was further investigated by indirect detection using plasma samples of the birds to detect antibodies specific for H. meleagridis and worms by ELISA. The infection with H. meleagridis was confirmed by histopathology and immunohistochemistry to detect the flagellate in the cecum of representing birds. The excretion of H. meleagridis could already be observed from the 2nd wpi in some birds and increased to 100% in the last week of the experiment in all groups independent of the genetic line. This increase could be confirmed by ELISA, even though the number of excreted H. meleagridis per bird was generally low. Overall, histomonads were detected in 60% to 78% of birds with temporary differences between the different genetic lines, which also showed variations in the EPG and worm burden of both nematodes. The infection with H. Gallinarum eggs contaminated with H. meleagridis led to a permanent excretion of the flagellate in host feces. Differences in the excretion of H. meleagridis in the feces of genetically different host lines occurred intermittently. The excretion of the protozoan or its vector H. Gallinarum was mostly exclusive, showing a negative interaction between the two parasites in the same host.
Manuel Stehr - One of the best experts on this subject based on the ideXlab platform.
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excretion of histomonas meleagridis following experimental co infection of distinct chicken lines with Heterakis Gallinarum and ascaridia galli
Parasites & Vectors, 2021Co-Authors: Gurbuz Das, Manuel Stehr, Cornelia C. Metges, Lukas Wachter, Ivana Bilic, Beatrice Grafl, Patricia Wernsdorf, Michael Hess, Dieter LiebhartAbstract:Histomonosis is a severe re-emerging disease of poultry caused by Histomonas meleagridis, a protozoan parasite which survives in the environment via the cecal worm Heterakis Gallinarum. Following infection, the parasites reside in the ceca and are excreted via host feces. In the present work, male birds of conventional broiler (Ross 308, R), layer (Lohmann Brown Plus, LB) and a dual-purpose (Lohmann Dual, LD) chicken line were infected with 250 embryonated eggs of Ascaridia galli and Heterakis Gallinarum, respectively, with the latter nematode harboring Histomonas meleagridis, to investigate a co-infection of nematodes with the protozoan parasite in different host lines. In weekly intervals, from 2 to 9 weeks post infection (wpi), individual fecal samples (n = 234) from the chickens were collected to quantify the excretion of H. meleagridis by real-time PCR and to determine the number of nematode eggs per gram (EPG) in order to elucidate excretion dynamics of the flagellate and the nematodes. This was further investigated by indirect detection using plasma samples of the birds to detect antibodies specific for H. meleagridis and worms by ELISA. The infection with H. meleagridis was confirmed by histopathology and immunohistochemistry to detect the flagellate in the cecum of representing birds. The excretion of H. meleagridis could already be observed from the 2nd wpi in some birds and increased to 100% in the last week of the experiment in all groups independent of the genetic line. This increase could be confirmed by ELISA, even though the number of excreted H. meleagridis per bird was generally low. Overall, histomonads were detected in 60% to 78% of birds with temporary differences between the different genetic lines, which also showed variations in the EPG and worm burden of both nematodes. The infection with H. Gallinarum eggs contaminated with H. meleagridis led to a permanent excretion of the flagellate in host feces. Differences in the excretion of H. meleagridis in the feces of genetically different host lines occurred intermittently. The excretion of the protozoan or its vector H. Gallinarum was mostly exclusive, showing a negative interaction between the two parasites in the same host.
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excretion of histomonas meleagridis following experimental co infection of distinct chicken lines with Heterakis Gallinarum and ascaridia galli
Parasites & Vectors, 2021Co-Authors: Gurbuz Das, Manuel Stehr, Cornelia C. Metges, Lukas Wachter, Ivana Bilic, Beatrice Grafl, Patricia Wernsdorf, Michael Hess, Dieter LiebhartAbstract:BACKGROUND Histomonosis is a severe re-emerging disease of poultry caused by Histomonas meleagridis, a protozoan parasite which survives in the environment via the cecal worm Heterakis Gallinarum. Following infection, the parasites reside in the ceca and are excreted via host feces. In the present work, male birds of conventional broiler (Ross 308, R), layer (Lohmann Brown Plus, LB) and a dual-purpose (Lohmann Dual, LD) chicken line were infected with 250 embryonated eggs of Ascaridia galli and Heterakis Gallinarum, respectively, with the latter nematode harboring Histomonas meleagridis, to investigate a co-infection of nematodes with the protozoan parasite in different host lines. METHODS In weekly intervals, from 2 to 9 weeks post infection (wpi), individual fecal samples (n = 234) from the chickens were collected to quantify the excretion of H. meleagridis by real-time PCR and to determine the number of nematode eggs per gram (EPG) in order to elucidate excretion dynamics of the flagellate and the nematodes. This was further investigated by indirect detection using plasma samples of the birds to detect antibodies specific for H. meleagridis and worms by ELISA. The infection with H. meleagridis was confirmed by histopathology and immunohistochemistry to detect the flagellate in the cecum of representing birds. RESULTS The excretion of H. meleagridis could already be observed from the 2nd wpi in some birds and increased to 100% in the last week of the experiment in all groups independent of the genetic line. This increase could be confirmed by ELISA, even though the number of excreted H. meleagridis per bird was generally low. Overall, histomonads were detected in 60% to 78% of birds with temporary differences between the different genetic lines, which also showed variations in the EPG and worm burden of both nematodes. CONCLUSIONS The infection with H. Gallinarum eggs contaminated with H. meleagridis led to a permanent excretion of the flagellate in host feces. Differences in the excretion of H. meleagridis in the feces of genetically different host lines occurred intermittently. The excretion of the protozoan or its vector H. Gallinarum was mostly exclusive, showing a negative interaction between the two parasites in the same host.
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Co-expulsion of Ascaridia galli and Heterakis Gallinarum by chickens.
International journal for parasitology, 2018Co-Authors: Manuel Stehr, Matthias Gauly, Q. Sciascia, Cornelia C. Metges, Gurbuz DasAbstract:Abstract Worm expulsion is known to occur in mammalian hosts exposed to mono-species helminth infections, whilst this phenomenon is poorly described in avian hosts. Mono-species infections, however, are rather rare under natural circumstances. Therefore, we quantified the extent and duration of worm expulsion by chickens experimentally infected with both Ascaridia galli and Heterakis Gallinarum, and investigated the accompanying humoral and cell-mediated host immune responses in association with population dynamics of the worms. Results demonstrated the strong co-expulsion of the two ascarid species in three phases. The expulsion patterns were characterized by non-linear alterations separated by species-specific time thresholds. Ascaridia galli burden decreased at a daily expulsion rate (e) of 4.3 worms up to a threshold of 30.5 days p.i., followed by a much lower second expulsion rate (e = 0.46), which resulted in almost, but not entirely, complete expulsion. Heterakis Gallinarum was able to induce reinfection within the experimental period (9 weeks). First generation H. Gallinarum worms were expelled at a daily rate of e = 0.8 worms until 36.4 days p.i., and thereafter almost no expulsion occurred. Data on both humoral and tissue-specific cellular immune responses collectively indicated that antibody production in chickens with multispecies ascarid infections is triggered by Th2 polarisation. Local Th2 immune responses and mucin-regulating genes are associated with the regulation of worm expulsion. In conclusion, the chicken host is able to eliminate the vast majority of both A. galli and H. Gallinarum in three distinct phases. Worm expulsion was strongly associated with the developmental stages of the worms, where the elimination of juvenile stages was specifically targeted. A very small percentage of worms was nevertheless able to survive, reach maturity and induce reinfection if given sufficient time to complete their life cycle. Both humoral and local immune responses were associated with worm expulsion.
Anna Schwarz - One of the best experts on this subject based on the ideXlab platform.
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pathobiology of Heterakis Gallinarum mono infection and co infection with histomonas meleagridis in layer chickens
Avian Pathology, 2011Co-Authors: Anna Schwarz, Gurbuz Das, Hansjorg Abel, Julia Humburg, Gerhard Breves, Matthias Gauly, Alexander Th A Weiss, Silke RautenschleinAbstract:Little is known about the induction and modulation of gut-associated immune reactions after nematode infection in the chicken. The objective of the present study was to compare the pathogenesis, induction of immune reactions and electrophysiological changes of the gut after mono-infection with Heterakis Gallinarum and after dual infection with H. Gallinarum and Histomonas meleagridis in layer chickens. In two experiments 3-week-old chickens were inoculated with embryonated H. Gallinarum eggs, which were positive for H. meleagridis. While birds of the first experiment were left untreated, those of the second experiment were treated with dimetridazol to prevent H. meleagridis co-infection. Mild to moderate histological lesions and local immune reactions with a significant increase in CD4(+), CD8α(+), TCRαβ(+) and TCRδγ(+) cells in the lamina propria and induction of the T-helper type 2 (Th2) cytokine interleukin-13 dominated the H. Gallinarum immune response at 2 weeks post infection. Co-infection with H. Gallinarum and H. meleagridis induced an increase in mRNA expression of the T-helper type 1 (Th1) cytokine interferon-γ, a decrease in splenic CD4(+) cells and severe destruction of the caecal mucosa in association with strong T-cell infiltration in the caecal lamina propria. There was no obvious effect on the chloride secretion of the caecal epithelium, which was investigated once the mucosa had almost recovered from the infection, in either experiment. These results suggest that the local T-cell reactions to nematode infections in chickens may be comparable with mammals and may be shifted from a Th2-dominated to a Th1-dominated response when accompanied by a protozoan infection.
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effects of dietary non starch polysaccharides on establishment and fecundity of Heterakis Gallinarum in grower layers
Veterinary Parasitology, 2011Co-Authors: Gurbuz Das, Hansjorg Abel, Julia Humburg, Anna Schwarz, Silke Rautenschlein, Gerhard Breves, Matthias GaulyAbstract:It was hypothesized that the establishment and fecundity of Histomonas meleagridis free Heterakis Gallinarum may be affected by dietary non-starch polysaccharides (NSPs). One-day-old female layer chicks (N=670) were fed ad libitum for 11wk one of the following diets in a three-times repeated experiment: basal diet (CON), basal diet plus pea bran rich in insoluble NSP (I-NSP), basal diet plus chicory root meal as a source of inulin rich soluble NSP (S-NSP). At the end of wk three, each feeding group was subdivided into an uninfected and an infected group of birds each being inoculated with a placebo or with 200 H. meleagridis free eggs of H. Gallinarum. The birds were slaughtered 8wk post infection and their worm burdens, the nematode egg excretion, caeca sizes and weights as well as intracaecal pH and volatile fatty acid (VFA) concentrations were determined. The NSP supplemented diets and also infection led to reduced body weights (BWs) of birds and impaired the feed conversion rate (P<0.001). The NSP supplemented diets increased average length of caecum (P<0.001) with S-NSP exerting a stronger effect than I-NSP (P<0.05). Full caeca weight was increased by S-NSP (P<0.001). Feeding S-NSP lowered intracaecal pH and molar proportion of acetate and increased that of butyrate compared to CON and I-NSP (P<0.001). Caecal pool of VFA was increased with S-NSP (P<0.001). The NSP-diets elevated incidence of infection (P<0.01), average number of larvae (P<0.009) and total worm burden (P<0.001) compared to CON. The daily amount of faeces increased in NSP-fed birds (P<0.001). Number of eggs per gram of faeces (EPG), number of eggs excreted per worm population of a bird within 24h (EPD) and female worm fecundity (EPD/female worm) were elevated after feeding S-NSP (P≤0.002), whereas I-NSP led to lower EPG/female worm (P<0.05). The EPD increased in the sequence of CON
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non starch polysaccharides alter interactions between Heterakis Gallinarum and histomonas meleagridis
Veterinary Parasitology, 2011Co-Authors: Gurbuz Das, Hansjorg Abel, Julia Humburg, Anna Schwarz, Silke Rautenschlein, Gerhard Breves, Matthias GaulyAbstract:Nutrition of the host animal may not only influence interactions between the host and its parasites, but also relations between different parasites species residing on the same host. We investigated effects of insoluble and soluble non-starch polysaccharides (NSP) on establishment and development of Heterakis Gallinarum in chicken being treated or left untreated against Histomonas meleagridis. Six groups of one-day-old birds were allocated to three diets, two on each diet. The birds were fed ad libitum either a basal diet (CON), or CON+insoluble NSP (I-NSP) or CON+soluble NSP (S-NSP) until an age of 11wk. At an age of 19d, one of each diet groups was prophylactically treated for 9d with dimetridazole (0.05%, w/v) via drinking water against histomonas. The remaining three groups were left un-treated. Two days after starting dimetridazole treatment (at 3wk), each of the 6 groups was divided into two sub-groups. One dimetridazole treated and one dimetridazole un-treated groups of birds on each diet (6 groups) were infected with 200 embryonated eggs of H. Gallinarum that were previously harvested from histomonas-carrying H. Gallinarum infected chickens. The remaining 6 groups of uninfected birds, either treated or left un-treated against H. meleagridis, served as controls. Worm burdens of infected birds were determined 8wk p.i. Treatment against H. meleagridis significantly increased incidence of H. Gallinarum infection and average worm length in all infected groups independent of the diet consumed (p 0.05). Both NSP supplemented diets resulted in lower (p<0.05) BW when compared with the CON diet, S-NSP being inferior to I-NSP (p<0.05). It is concluded that H. meleagridis harms the definitive host as well as H. Gallinarum. Both insoluble and soluble NSP supplemented diets favor H. Gallinarum infection while S-NSP additionally intensifies histomonas infection, which then impairs establishment and development of H. Gallinarum.
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the influence of non starch polysaccharides on experimental infections with ascaridia galli and Heterakis Gallinarum in layer chicken gallus gallus domesticus
2011Co-Authors: Anna SchwarzAbstract:Recent changes in legal requirements for layer-housing in European countries have led to the substitution of traditional cages with free-range systems and floor husbandry. In these systems the risk and the prevalence of gastro-intestinal parasitic infections are very high because of the close contact of the animals to their feces. Ascaridia galli (A. galli) and Heterakis Gallinarum (H. Gallinarum) are common poultry nematodes with worldwide distribution, which may contribute to substantial economic losses in alternative production systems. Previous studies in mammals demonstrated that local immune reactions and alterations in the intestinal physiology play an important role in the control of parasitic intestinal infections. It was shown that feed components such as non-starch polysaccharides (NSP) may modulate systemic and local gut-associated immune functions. No information is available on the influence of NSP on the local immune reactions and the course of nematode infections in chicken. The goal of the project was to investigate immunological and electro-physiological parameters in the intestine following experimental infection with A. galli and H. Gallinarum in chicken, as well as to characterize the influence of NSP on these parameters. Under different dietary conditions we investigated local and systemic T cell populations, induction of local Th1 and Th2 cytokines, the humoral immune response as well as electrophysiological epithelial functions in the intestine. In addition, we described the influence of H. meleagridis on the pathology of H. Gallinarum infection. As in mammalian species, mild to moderate T cell infiltrations in the intestinal lamina propria and induction of the Th2 cytokines IL-4 and IL-13 dominated the local immune reactions following both nematode mono-infections. In contrast to highly invasive intestinal nematodes, both parasites did not induce any systemic effects on spleen lymphocyte populations. This observation suggests that the immune response following A. galli and H. Gallinarum infection is primary localized in the gut. A parasite specific systemic IgG antibody response was observed in A. galli-infected birds. Co-infection with H. Gallinarum and H. meleagridis induced severe destruction of the cecal mucosa in association with strong T cell infiltrations, a shift from the Th2- to the Th1-type cytokine response, and elicited systemic immune reactions in the spleen. As it was previously shown in nematode infections in mammals, electrogenic absorption of alanin and glucose was impaired in A. galli-infected chicken. The alterations in the intestinal physiology were only observed in experiment with an increase in IL-4 and IL-13 cytokine mRNA expression in the intestinal mucosa. This may indicate that an interaction between the local immunological reactions and electro-physiological intestinal functions may also exist in avian species. In contrast to the studies in mammals, NSP did not significantly influence the gut-associated immune parameters and electro-physiological functions of the intestine in nematode infected as well as in non-infected chicken. The present study reveals that both A. galli and H. Gallinarum infections in layer chicken elicit local gut-associated immune reactions and changes in the intestinal electro-physiological functions which may be comparable to mammalian species.