Species Of Raillietina Research Articles

Assay for the simultaneous detection of Raillietina spp. (R. echinobothrida, R. tetragona, and R. cesticillus) and Ascaridia galli infection in chickens using duplex loop-mediated isothermal amplification integrated with a lateral flow dipstick assay

Raillietina species and Ascaridia galli are two of the significant intestinal parasites that affect chickens in a free-range system production. They destroy the intestinal mucosa layer, leading to several clinical symptoms such as weight loss, a slowed growth rate, and economic value loss. Thus, the objective of this study was to develop an assay for simultaneously detecting Raillietina spp. (R. echinobothrida, R. tetragona, and R. cesticillus) and A. galli in a single reaction using duplex loop-mediated isothermal amplification (dLAMP) coupled with a lateral flow dipstick (LFD) assay. The analytical specificity of the dLAMP-LFD assay showed a high specific amplification of Raillietina spp. and A. galli without non-target amplification. Regarding the analytical sensitivity, this approach was capable of simultaneously detecting concentrations as low as 5 pg/μL of mixed-targets. To evaluate the efficiency of the dLAMP assay, 30 faecal samples of chickens were verified and compared through microscopic examination. The dLAMP-LFD assay and microscopic examination results showed kappa values of Raillietina spp. and A. galli with moderate (K= 0.615) to high (K= 1) agreements, respectively, while the McNemar’s test indicated that the efficiency between assays was not significantly different. Therefore, the developed dLAMP-LFD assay can be used as an alternative screening method to the existing classical method for epidemiological investigation, epidemic control, and farm management, as well as for addressing poultry health problems.

Morphological and phylogenetic analysis of Raillietina spp. in indigenous chickens (Gallus gallus domesticus) in Bangladesh

Raillietina spp. (Cestoda: Davaineidae), the most common cestodes in indigenous chickens, cause a substantial production loss in poultry industry in Bangladesh. Here, we estimated the prevalence, confirmed the species and determined the genetic pattern of species of Raillietina using molecular tools. We collected and examined 375 chickens randomly from household of different villages of Mymensingh sadar and Gouripur upazila, Mymensingh district and adult parasites were isolated and identified. Genomic DNA was extracted from collected parasites, amplified ITS-2 and ND-1 genes, sequenced and analyzed. Out of 375 samples, 270 (72.0%) were found positive with Raillietina species and mean worm burden was 10.46 ± 0.56. Microscopically, three species of Raillietina, such as R. cesticillus (37.9%), R. echinobothrida (41.1%) and R. tetragona (52.8%) were detected on the basis of their morphological features. The total length, length and width of scolex, sucker and rostellum were also measured. Among different factors, age, farming nature and flock size of chickens were significantly (p < 0.05) influenced Raillietina infections. For further validation, the sequences of ITS-2 gene generated in this study were matched with reference sequences of R. cesticillus, R. echinobothrida and R. tetragona and found 99.63% − 100% similarity. The phylogenetic analyses of ITS-2 and ND-1 sequences were clustered together with the reference sequences of R. cesticillus, R. echinobothrida and R. tetragona confirming microscopic identification. This is the first confirmation of species of Raillietina along with the prevalence of the species, which will be helpful for the formulation of a control strategy and provide basic information for further molecular study.

Molecular detection of cestoda in black francolin (Francolinus francolinus) of Babylon Province, Iraq

Cestodes or tapeworms (Class Cestoda, phylum Platyhelminthes) are widespread parasites of birds, as they cause various damages, which may lead to the death of their hosts, especially when the infection is severe. The Black Francolin belongs to the Phasianidae family of pheasants and, in the order Galliformes, the gallinaceous birds, and it is called Francolinus francolinus. Considering it as a local bird in Asia, it was referred to as the black partridge. The current study was conducted from January to October 2019 to determine the Cestoda infections within F. francolinus. Thirty-five birds from F. francolinus were examined for the presence of cestoda, of which 17 birds (48.57%) were infected with cestoda parasites. Molecular diagnosis based on sequences of cytochrome c oxidase 1 (COI) gene regions was performed to confirm the diagnosis of this cestoda. This revealed a close identification of up to 93.44-100% for COI gene regions with other cestoda species obtained from GenBank. Phylogenetic analysis supported the placement of this species within three families, Davaineidae, Taeniidae, and Hymenolepididae, with close relationships to the previously described species of Raillietina sp., R. mahnerti, R. hymenolepidoides, Ophryocotyloides dasi, Rodentolepis nana and Hydatigera parva based on the COI gene regions. This is the first study in Iraq to diagnose Cestoda in birds by molecular methods, where five species of cestoda parasitic on F. francolinus were recorded for the first time in Iraq.

A Cross-Sectional Survey of Gastrointestinal Parasites in an Ornithological Garden.

Captive birds in collections may be infested with a wide range of parasites. Globally, information on parasitic infections and their health implications in ornithological collections are scarce. In the present study, the prevalence of parasitic infections in an ornithological garden in Tehran was investigated. Samples (n = 109) from various bird species were collected. Direct wet smear, sedimentation, flotation with Sheather's sugar, and modified Ziehl-Neelsen and Giemsa staining were used for parasite screening. Parasites were identified in 57 (52.3%, 95% confidence interval [CI] 42.9-61.7) samples, with protozoans being the most frequently observed organisms, including Cryptosporidium species, Eimeria species, Isospora species, Trichomonas species, and Histomonas species. Helminths were observed in 29 (26.6%, 95% CI 18.3-34.9) of the samples and included strongyles, Capillaria species, and Raillietina species. Ectoparasites were rarely recovered, but 2 species were identified: the poultry shaft louse (Menopon gallinae) and the fowl tick (Argas persicus). Free-ranging birds were significantly (P < 0.001) more likely to have parasites in their feces than caged birds. Fecal parasitic infections were order dependent and more prevalent in the Anseriformes and Galliformes (P < 0.05). The frequency of gastrointestinal parasites was notable in the investigated collection. In open natural bird gardens, such as in the present study, the probable transmission routes and sources of the parasitic infections are most likely via the free-ranging avian species. It is wise to recommend regular screening of the birds in these gardens to improve preventive control measures. Additionally, parasite genotyping should be considered to clarify our understanding of the epidemiology of zoonotic and nonzoonotic parasites.

Intestinal cestode infection of Raillietina species in a 9 weeks old broiler in Umuahia, Abia State, Nigeria – A Case Report

This case report presents an intestinal cestode infection of Raillietina species in broilers. Live broiler birds that were 9 weeks old were seen to be infected with cestodes during a farm visit. Post mortem examination was carried out and samples of the intestines, live tapeworms and faeces were collected. On post mortem examination, the intestines were filled with whitish worms, the tapeworms were identified using microscopic examination as Raillietina species but no eggs of Raillietina species were observed following fecal examination. Although cestode infections with this species usually do not adversely affect humans following consumption, they are of economic importance as infections in birds can cause weight loss, growth problems and weakness. The essence of this report was to highlight and identify that cestode infections with Raillietina species can occur in broilers which is uncommon and the reason further investigation with microscopic examination was carried out following the negative result from the faecal examination

Heteroplasmic mitochondrial genomes of a Raillietina tapeworm in wild Pangolin

BackgroundRaillietina species belong to the family Davaineidae, which parasitizes in a wide variety of mammals and birds, causing stunted growth, lethargy, emaciation, and digestive tract obstruction. However, only a limited number of Raillietina species have been identified in wild animals.MethodsWe analyzed and annotated the complete mitochondrial (mt) genome of a worm from the intestine of a wild pangolin using Illumina sequencing of whole genomic DNA.ResultsThese findings showed the presence of two mtDNA sequences in Raillietina sp., designated as mt1 and mt2, with the lengths of 14,331 bp and 14,341 bp, respectively. Both the mts genomes of Raillietina sp. comprised 36 genes, containing 12 protein-coding genes (PCGs), 2 ribosomal RNAs, and 22 transfer RNAs. Gene arrangements of both mt genomes of Raillietina sp. were similar to those of most flatworms, except for taeniids, which shift positions between tRNAL1 and tRNAS2 genes. Twenty of 22 tRNA secondary structures of Raillietina sp. had a typical cloverleaf structure similar to Raillietina tetragona. Sequence differences between the mt1 and mt2 genomes were 4.4%, and this difference arises from the mtDNA heteroplasmic mutations. Moreover, heteroplasmic mtDNA mutations were detected in PCGs, tRNAs, rRNAs, NCRs, and intergenes, but the highest proportion of heteroplasmy of 79.0% was detected in PCGs, indicating the occurrence of mtDNA heteroplasmy in Raillietina sp. To our knowledge, this is the first report of mtDNA heteroplasmy in tapeworm parasites. Phylogenetic analyses of 18S rRNA, ITS2, and 12 PCG sequences demonstrated that the worm was clustered with other Raillietina species in the Davaneidae family.ConclusionsWe found a novel Raillietina species in wild pangolin with the existence of mitochondrial DNA heteroplasmy. Thus, these findings provide insights into the heterogeneity of the mt genome in parasitic cestodes, and mt genome data contributes to the understanding of pangolin-parasitic cestodes in terms of their molecular biology, epidemiology, diagnosis, and taxonomy.Graphical

High-performance triplex PCR detection of three tapeworm species belonging to the genus Raillietina in infected poultry

Chickens and ducks are important sources of essential proteins and nutrition for global consumption, especially their eggs and meat. Tapeworm infections in chickens and ducks are the cause of serious poultry health and economic problems in the processing of livestock and food production systems. Raillietina are cosmopolitan in distribution and are possibly the most common tapeworm parasites. There are three important species regarding avian infection, with different pathogenicity, including Raillietina echinobothrida, R. tetragona, and R. cesticillus. Co-infection diagnosis of these tapeworms using morphological analysis can be performed, but this is time-consuming and complicated. Therefore, this study aimed to develop a triplex PCR for the detection and discrimination of three Raillietina species. The triplex PCR assay specifically amplified target DNAs with no inter-specific interference and produced a specific band for each species. According to the specificity test, there was no cross-amplification with the DNA template of related parasites and their hosts. The lowest detectable DNA concentrations were evaluated and provided sensitivities of 0.5 pg/μL for R. echinobothrida, 5 pg/μL for R. tetragona, 50 fg/μL for R. cesticillus, and 5 pg/μL for the combination of DNA from all three species. Simultaneous detection limits of egg capsules and gravid proglottids was also performed, with and without feces. The interference of feces in the reaction was related to a decrease in sensitivity, but simultaneous detection of three Raillietina species in amounts lower than one gravid proglottid and ten egg capsules was still successful. Thus, this study is the first triplex PCR assay for Raillietina detection and can be utilized as an alternative diagnostic tool for the detection and discrimination of R. echinobothrida, R. tetragona, and R. cesticillus infection in poultry through the verification of fecal specimens. In addition, it could improve the performance of specific treatments and promote veterinary healthcare.

Molecular detection of three intestinal cestode species (Raillietina echinobothrida, R. tetragona, R. cesticillus) from poultry in Thailand

ABSTRACT Cestodes belonging to the genus Raillietina are a major veterinary health problem affecting the poultry industry, particularly chickens (Gallus gallus domesticus) and ducks (Anas playtrhynchos domesticus). The traditional method for accurately detecting this cestode based on their morphological characteristics is rather difficult due to the large number of morphological similarities. Consequently, this study aimed to develop specific primers for R. echinobothrida, R. tetragona, and R. cesticillus detection that could be used to indicate epidemic areas for protection and infection control. Specific primers were manually designed based on the internal transcribed spacer 2 region and validated, establishing the optimal temperature, final concentration in PCR mixture, specificity, and sensitivity of each primer set. The results showed that the primers amplify specific species without cross-amplifying other parasites and hosts. The PCR products were about 473, 352, and 397 bp long for R. echinobothrida, R. tetragona, and R. cesticillus, respectively. The sensitivity test demonstrated that R. echinobothrida and R. cesticillus-specific primers detect a minimum of 5×10−2 ng DNA, while R. tetragona-specific primers detect a minimum of 0.5 ng genomic DNA. The specific primers successfully developed in this study might be useful for detecting cysticercoids in intermediate hosts or adult stages in poultry for epidemiological surveys, management and control of infection. RESEARCH HIGHLIGHTS This study established specific primers for Raillietina species detection. The ITS2 region is an effective molecular marker for Raillietina identification.

Novel high-performance detection of Raillietina echinobothrida, Raillietina tetragona, and Raillietina cesticillus using loop-mediated isothermal amplification coupled with a lateral flow dipstick (LAMP-LFD)

Cestodes belonging to the genus Raillietina are a major veterinary health problem in the poultry industry, especially in chickens (Gallus gallus domesticus) and ducks (Anas playtrhynchos domesticus). In this study, loop-mediated isothermal amplification coupled with a lateral flow dipstick (LAMP-LFD) assay was established and validated for the detection of R. echinobothrida, R. tetragona, and R. cesticillus in one reaction. The LAMP-LFD assay can be completed in 75 min under isothermal conditions at 66 °C and the results can be obtained by observation with the naked eye. This assay was very specific and had no cross-amplification with other closely related parasites (Cotugnia sp., Diorchis formosensis, Fimbriaria sp., Echinostoma sp., E. miyagawai, Hypoderaeum conoideum, Prosthogonimus cuneatus, and Ascaridia galli) or their definitive hosts (G. g. domesticus, A. p. domesticus). The sensitivity of the LAMP-LFD assay was detected with three Raillietina species at 0.5 ng, which was enough for gravid proglottid DNA detection. The accuracy test showed that the LAMP-LFD assay demonstrated accurate verification results when compared to morphological results. This is a novel LAMP-LFD assay that is highly specific and sensitive for the detection of Raillietina species. It can be applied to detection for epidemiological investigations, monitoring programs, surveillance, control, and to solve veterinary health problems for the poultry industry in Raillietina endemic areas.

Detection of Raillietina saudiae from the domestic pigeon in Saudi Arabia through 18S and 28S rDNA genes.

Raillietina saudiae is a well-studied avian gastrointestinal parasite belonging to the family Davaineidae and is the most prevalent cyclophyllid tapeworm infecting pigeon in Saudi Arabia. The present study considered as a complementary analysis of Al-Quraishy et al. (2019; Parasitol Int 71, 59-72) with molecular studies for two ribosomal DNA genes employed for precise recognition of this Raillietina species. The annotated partial 18S and 28S rDNA gene regions were found to be 888 and 900bp long that utilized further to elucidate their genetic relationships at species level using maximum likelihood method. The query sequence of R. saudiae is well aligned and placed within the Davaineidae family, with the same clade of all species of Raillietina that well separated from other cyclophyllidean cestodes especially taeniid and hymenolepid species. Sequence data recorded the monophyly of Raillietina species. The current phylogeny supports the usage of the partial 18S and 28S rDNA genes as reliable markers for phylogenetic reconstructions.

Molecular characterization of Raillietina isolates from the gastrointestinal tract of free range chickens (Gallus Gallus domesticus) from the southern region of Zimbabwe using the 18S rDNA gene.

Parasitic diseases are among the major constraints of poultry production. The common internal parasitic infections occurring in poultry include cestodes and other gastrointestinal helminths. The aim of this study was to characterize Raillietina spp. from the gastrointestinal tract of free-range chickens using 18S rDNA genes. This was achieved through the DNA extraction from tapeworms isolated from the gastrointestinal tract of routine slaughtered free-range chickens using 18S and amplifying the partial 18S rDNA genes using PCR. A total of 34 intestine samples were collected from 9 different areas in Matabeleland region and tapeworms were isolated for microscopic examination and morphological characterization. All 34 chickens examined had tapeworms and morphological characterization confirmed those used in the study as belonging to the Raillietina group. DNA extraction was then successfully carried out for 9 cestode isolates followed by the PCR amplification of the 18S genes. The products were sequenced and 4 of the 9 isolates were positively identified using BLAST as Raillietina tunetensis and the other 5 were only identified as Raillietina spp. These sequences were then aligned with other known sequences of Raillietina isolates from GenBank and a phylogenetic tree was constructed using the neighbor-joining method and distance computed using the maximum composite method. The phylogenetic tree showed that three of the unidentified Raillietina species are in the neighboring position with Raillietina sonini whilst the other two are in the neighboring position with Raillietina tetragona. This is the first record of R. tunetensis in Gallus Gallus domesticus from Zimbabwe. This clustering on the phylogenetic tree however, did not differentiate samples according to geographical location showing that this tool can be used to infer phylogenetic data for speciation.

Helminth infection of layer and dual-purpose chickens kept under small scale intensive production system, Ethiopia

Losses due to reduced productivity caused by helminthiasis are economically important to the poultry industry. There are a few research reports in the prevalence of helminth-parasites in the different poultry production systems. A cross sectional study was conducted with the aim of estimating the prevalence of helminth infections in exotic layer and dual-purpose chickens, kept under small scale intensive farms of selected towns, Ethiopia: Addis Ababa (Highlands) and Debre Zeit, Haramaya, Hawassa and Kombolcha (Midlands) climatic zones. Towns and farms were purposively identified while chickens from each farm were randomly selected for fecal sample collection and necropsy examination. A total of 1009 fresh fecal samples and thirty-three chickens were collected from chickens of different breeds. Helminth egg and adult parasite identification was processed through coproscopic and necropsy examination methods, respectively. The overall prevalence of helminth infection was 66(%). A statistically significant difference was found in the prevalence of helminthiasis among study sites (P 0.05) among age groups. Three species of nematodes as Ascaridia galli (52%), Heterakis gallinarum (57%) and Capillaria species (1%) and one species of cestode: Raillietina species (3%) were identified. Regular check up for helminth infection and application of appropriate prevention and control measures are important. Key words : Chicken; Exotic; Intensive; Helminth-infection; Small-scale

Gastrointestinal helminths and their predisposing factors in different poultry management systems; Haromaya, Ethiopia

Among several diseases, gastrointestinal parasites affect poultry production through retarded growth and reduced productivity. The severity varies according to management system and associated predisposing factors. Epidemiology of chicken gastrointestinal helminths were studied using coprological and necropsy examination, with the objectives to estimate the prevalence, identify species of helminths and associated predisposing factors in Haromaya town from November 2011 to April 2012. Fecal samples from selected chicken were collected from both intensive and extensive farms. Coprological examination on 384 chicken and 24 post mortem examinations were conducted. Out of 384 samples examined, 51.8% were positive of which a high prevalence of 110(28.6%) Ascaridia galli followed by 33(8.6%) of Heterakis gallinarum, 11(2.8%) of Raillietina species and 44(11.5%) mixed infection were recovered. Factors for the occurrence of GIT helminths were investigated using logistic regression models; where each assumed predisposing factor analyzed using uni-variable and followed by multi-variable logistic regression to determine the interaction and power of influence among factors. Accordingly, statistically significant difference (p&lt;0.05) was observed when prevalence of helminths compared with breed, sex, age and management system separately using univariable logistic regression; whereas, when all predisposing factors subjected together using multi-variable backward stepwise analysis, it showed that the odds of local, Fayoumi and White Leghorn breeds had odds of (OR= 6.4, 50.8 and 6.9) more likely to be affected than Bovan Brown breed with significant difference (p&lt;0.05). Male birds were 1.9 times more likely to be affected than female birds and birds in extensive management system were 2.8 times more likely to be affected than intensive farming system. The study indicated that gastrointestinal (GIT) helminths were more prevalent in extensive management system than in intensive management system, the finding was associated with poor management system or due to poor bio-security. Therefore, there is a need to improve hygienic situation, especially in area where extensive management system prevails.Keywords: Gastrointestinal; Haromaya; Helminths; Poultry; Production systems

Morphology and Molecular Phylogeny of Raillietina spp. (Cestoda: Cyclophyllidea: Davaineidae) from Domestic Chickens in Thailand.

Raillietina species are prevalent in domestic chickens (Gallus gallus domesticus) in Phayao province, northern Thailand. Their infection may cause disease and death, which affects the public health and economic situation in chicken farms. The identification of Raillietina has been based on morphology and molecular analysis. In this study, morphological observations using light (LM) and scanning electron microscopies (SEM) coupled with molecular analysis of the internal transcribed spacer 2 (ITS2) region and the nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) gene were employed for precise identification and phylogenetic relationship studies of Raillietina spp. Four Raillietina species, including R. echinobothrida, R. tetragona, R. cesticillus, and Raillietina sp., were recovered in domestic chickens from 4 districts in Phayao province, Thailand. LM and SEM observations revealed differences in the morphology of the scolex, position of the genital pore, number of eggs per egg capsule, and rostellar opening surface structures in all 4 species. Phylogenetic relationships were found among the phylogenetic trees obtained by the maximum likelihood and distance-based neighbor-joining methods. ITS2 and ND1 sequence data recorded from Raillietina sp. appeared to be monophyletic. The query sequences of R. echinobothrida, R. tetragona, R. cesticillus, and Raillietina sp. were separated according to the different morphological characters. This study confirmed that morphological studies combined with molecular analyses can differentiate related species within the genus Raillietina in Thailand.

Molecular characterization of the Indian poultry nodular tapeworm, Raillietina echinobothrida (Cestoda: Cyclophyllidea: Davaineidae) based on rDNA internal transcribed spacer 2 region

The nodular tapeworm, Raillietina echinobothrida is a well studied avian gastrointestinal parasite of family Davaineidae (Cestoda: Cyclophyllidea). It is reported to be the largest in size and second most prevalent species infecting chicken in north-east India. In the present study, morphometrical methods coupled with the molecular analysis of the second internal transcribed spacer (ITS2) region of ribosomal DNA were employed for precise identification of the parasite. The annotated ITS2 region was found to be 446bp long and further utilized to elucidate the phylogenetic relationships and its species-interrelationships at the molecular level. In phylogenetic analysis similar topology was observed among the trees obtained by distance-based neighbor-joining as well as character-based maximum parsimony tree building methods. The query sequence R. echinobothrida is well aligned and placed within the Davaineidae group, with all Raillietina species well separated from the other cyclophyllidean (taeniid and hymenolepid) cestodes, while Diphyllobothrium latum (Pseudophyllidea: Diphyllobothriidae) was rooted as an out-group. Sequence similarities indeed confirmed our hypothesis that Raillietina spp. are neighboring the position with other studied species of order Cyclophyllidea against the out-group order Pseudophyllidea. The present study strengthens the potential of ITS2 as a reliable marker for phylogenetic reconstructions.

The Spatial Distribution of Five Species of Raillietina Infecting the Emu, Dromaius Novaehollandiae

SummaryThe intensity and distribution of five species of Raillietina: R. australis, R. beveridgei, R. chiltoni, R. dromaius and R. mitchelli, in the intestine of farmed and wild emus, Dromaius novaehollandiae was determined. All of the emus were infected with cestode species that occupied predictable portions of intestine. Site segregation appeared to be dependent on species intensity. Species with morphologically similar genitalia appeared to separate suggesting that species segregation may facilitate cross fertilisation in the hermaphroditic parasite.

Cysticercoids of five species of Raillietina Fuhrmann, 1920 (Cestoda: Davaineidae) in ants, Pheidole sp., from emu farms in Australia.

Cysticercoids of five species of Raillietina, R. australis (Krabbe, 1869) Fuhrmann, 1924, R. beveridgei O'Callaghan, Davies & Andrews, 2000, R. chiltoni O'Callaghan, Davies & Andrews, 2000, R. dromaius O'Callaghan, Davies & Andrews, 2000 and R. mitchelli O'Callaghan, Davies & Andrews, 2000, parasitic in the emu Dromaius novaehollandiae Latham, are described. Each species was identified on the basis of the number and size of the rostellar hooks, which correspond to those of adult worms. Cysticercoids were recovered from the haemocoele of the gaster of ants belonging to the genus Pheidole (Hymenoptera: Formicidae) in Australia. There was a trend towards an inverse relationship between the size of the cysticercoids and the parasite burden in the intermediate host.

Raillietina (Raillietina) guaricana n. sp. (Cestoda-Davaineidae), parasite of wild rats from the environmental protection area of Guaricana, Paraná, Brazil

Raillietina (Raillietina) guaricanae n. sp. is described from the wild rats Oryzomys intermedius, O. nigripes and O. ratticeps, captured in the Environmental Protection Area of Guaricana, from November 1988 to December 1989. Raillietina (Railietina) guaricanae n. sp. is closely related to the Neotropical mammalian Raillietina, however it differs by the fewer number of rostellar hooks, and tests different number of eggs capsules and host species. The number of known species of Raillietina (Raillietina), parasites of mammals in the Neotropical Region, is increased to four.

Aspects of the biology and parasitology of the speckled pigeon Columba guinea L. from Ahmadu Bello University Campus, Zaria, North Central State, Nigeria

The nesting activity, food, fat content and parasites of the speckled pigeon Columba guinea L. from Ahmadu Bello University at Zaria in Nigeria were studied during 1973. Five parasite species were found; the digenean trematode Echinostomum revolutum (Froelich), the cestodes Aporina delafondi (Raillet) and two species of Raillietina and the hippoboscid fly Pseudolynchia canariensis Macquart. The cestodes were the most important parasites since 92% of all birds examined were infected. Male birds had a heavier cestode load than female birds. The nesting season was essentially from October to April with a peak of activity during December and January. Male birds were heavier and showed greater variation in morphometric characteristics than females. Immature birds were lighter than adults but their wing and bill lengths were similar. These pigeons were mainly grain eating birds and the abundance of ground-nuts, guinea corn, rice and millet as items of food apparently coincided with the planting and harvesting seasons. Pigeons in the nesting season had fewer fat deposits in the heart and smaller numbers of cestodes which were, however, heavier than those from pigeons in the non-nesting season. Male pigeons were lighter in the nesting season than males in the non-nesting season and had less fat but a greater parasite load in the nesting season than females.

Raillietina (Raillietina) loeweni sp. n. (Cestoda: Davaineidae) from the Hare in Kansas, with Notes on Raillietina of North American Mammals

Raillietina (Raillietina) loeweni sp. n. is described from the black-tailed jackrabbit (Lepus californicus melanotis Mearns) from western Kansas. A key is given for the species of Raillietina of North American mammals. Subfamily and generic emendations are made to include R. loeweni. Data are given on the seasonal and monthly prevalence of this cestode in the host population in the study area. Surveys of the parasitic helminths of hares (Lepus spp.) and rabbits (Sylvilagus spp.) in the United States and Canada have revealed Raillietina infections as follows: R. salmoni (Stiles, 1896) from rabbits in Texas (Price, 1928); Raillietina sp. from Lepus alleni from Arizona (Vorhies and Taylor, 1933); R. retractilis (Stiles, 1896) from Sylvilagus spp. from Wyoming (Honess, 1935); R. salmoni from cottontail rabbits in Alabama (Moore, 1939); R. retractilis from cottontail rabbits in California (Herman and Jankiewicz, 1943); R. retractilis from S. nuttalli grangeri, S. auduboni baileyi, S. aud. arizonae, and L. townsendi campanius; R. salmoni from S. aud. arizonae, S. floridanus, and L. cal. melanotis in Wyoming (Honess and Winter, 1956); R. retractilis from L. cal. deserticola in Utah (Grundmann, 1958); R. retractilis from L. californicus in California (Lechleitner, 1959); and R. salmoni (later Received for publication 20 September 1963. * This study was supported in part by grant No. E-1676, National Institutes of Health; by Kansas State University, Agricultural Experiment Station Project No. A-488; and by the Kansas Forestry Fish and Game Commission. Contribution No. 326, Department of Zoology, Kansas State University, Manhattan, and Zoology Series No. 357. t A portion of a dissertation presented by Monroe H. Bartel in partial fulfillment of the requirements for the degree Doctor of Philosophy in Parasitology at Kansas State University, Manhattan. Present address: Department of Natural Sciences, Moorhead State College, Moorhead, Minnesota. identified by senior author as R. loeweni sp. n.) from L. cal. melanotis in Kansas (Lyons, Hansen, and Tiemeier, 1960; Bartel, 1960). A helminth parasite survey was conducted on the black-tailed jackrabbit, Lepus californicus melanotis Meams, from January 1960, through November 1961, and June through October exclusive of September 1962, near Lakin in Kearny County, Kansas. One hundred ninety hares (70.4%) of 270 examined harbored Raillietina (R.) loeweni sp. n. Inference of the monthly infection rates of the host population by the cestode was based on the infections of ten hares collected each month. The sample of ten hares, showing no shot damage to the intestinal tract, was taken from larger monthly collections of 11 to 37 hares collected within an 11-mile radius of Lakin, Kansas, north of the Arkansas River. The hares were classified as adult or juvenile on the basis of body size, condition of reproductive organs, and the degree of epiphyseal closure of the humeri according to the method of Plenert (1962). The cestode is named in honor of Dr. S. L. Loewen, parasitologist, Tabor College, Hillsboro, Kansas. The description is based on eight gravid cestodes fixed in Ward's fixative and stained in Delafield's hematoxylin. Additional specimens were observed fresh or cleared in lactophenol. Egg pouches, teased from fixed gravid proglottids, were measured and counted. The size of eggs and oncospheres was determined from eggs teased from living proglottids. Living oncospheres were stained with 1 : 10,000 neutral red or 1: 5,000 brilliant