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• Effects of T. colubriformis infection on diet passage rate and performance were evaluated. • Infected lambs showed no signs of anorexia or impairment of feed intake. • T. colubriformis infection promoted higher digesta flow in the rumen-reticulum segment. • T. colubriformis infection affected short chain fatty acids production. • Chronic infection by T. colubriformis showed negative impact on lamb production. In this study we aimed to evaluate the effect of Trichostrongylus colubriformis infection on digesta passage rate, rumen fermentation and lamb performance. Eighteen three-month-old Santa Ines castrated male lambs (16.9 ± 1.43 kg of body weight) were randomly distributed in two experimental treatments: Infected with T. colubriformis (I, n = 9) and Uninfected (U, n = 9). The I lambs received a total of 45,000 L 3 larvae of T. colubriformis (5,000 infective larvae, three times per week for three weeks). Daily feed intake was assessed using the I lambs as a reference for their respective pairs on the U group (pair-fed). Weight, body condition score and faeces (stool) samples were obtained every 15 days for 75 days. In both treatments, faecal egg count (FEC), digesta passage rate, rumen fermentation parameters, protozoa count and short chain fatty acids (SCFA) were evaluated. The lambs presented moderate infection (FEC = 620). The retention time of the digesta in the rumen-reticulum segment was lower (P < 0.05) in I lambs. The I lambs presented no inappetence, however, lower concentrations of total SCFA and butyrate, while higher acetate concentration were observed in these lambs (P < 0.05). The present findings highlight that T. colubriformis infection decreased the retention time (solid and liquid content) of the digesta in the rumen-reticulum, as well as negatively affected lamb growth. [ABSTRACT FROM AUTHOR]

The early life history of Rafflesia R.Br. is hidden by its cryptic nature. Being a holoparasitic plant, early growth and development of species in this genus have been suggested to occur inside the host plant. In this study, using microscopic analyses, we examined how Rafflesia patma Blume grows from a simple clump of cells or protocorm inside the cambium tissue of Tetrastigma leucostaphylum (Dennst.) Alston, its host plant. We further show how the protocorm expands in about 2 months into an early form of a flower knob or bud, just before the flower begins to emerge from the host plant vine. Our study suggests that the endophyte, R. patma , spreads within T. leucostaphylum vascular cambium tissue in a linear manner, but not as a continuous strand. We suspect that the parasitic endophyte spreads inside the host vascular cambium and is pushed farther away from its point of origin to another part of the host as the host vine cambium fusiform initial cells divide and enlarge over months. Moreover, the protocorm matures in the cambium region of the T. leucostaphylum vine which lies close to the xylem, and grow outwards, bursting through the host phloem, then the host cortex, and finally towards the host periderm as it begins to emerge. Although we believe this might be the closest prediction on how Rafflesia develops at an early stage and is distributed within its host body, a future analysis of endophytic tissue growth in a controlled environment, such as the use of tissue culture, is required to strengthen our findings. • Rafflesia patma Blume is a holoparasitic plant. • Rafflesia patma parasitizes the cambium tissue of Tetrastigma leucostaphylum. • We use microscopic analyses to assess protocorm growth and flower knob formation. • Rafflesia patma spreads within T. leucostaphylum vascular cambium linearly. • The protocorm matures in the cambium region of the T. leucostaphylum vine. [ABSTRACT FROM AUTHOR]

Oleaginous microalgae are an important potential feedstock for biodiesel production. However, a problem in mass cultivation of microalgae is the frequent occurrence of infection by algal parasites. In the present study, an endoparasite WZ01 was isolated from an open raceway pond of oleaginous Graesiella sp. WBG-1, and caused epidemics resulting in algal population collapse. According to 18S rDNA-based phylogenetic analyses, morphology, ultrastructure and life cycle, strain WZ01 was identified as a member of Aphelidea, Amoeboaphelidium protococcarum , although it had some minor differences from A . protococcarum X-5 and FD95. Examination via transmission electron microscopy demonstrated that zoospores of the parasite WZ01 were amoeboid, which can produce two types of pseudopodia (multiple filopodia and short anterior lamellipodium), but the pseudocilium was not observed. Interestingly, amoeboid zoospores contained numerous dense-body vesicles, which have not been previously described. Moreover, our results revealed the presence of a microtubule inside the penetration tube, indicating that the contents of the cyst were injected into the host not only by vacuole pressure but also by using a microtubule-mediated mechanism. In addition, of the 42 tested algal species, only cultures of coccoid green algae Chlorococcum sp. A213 and Chlorococcum sp. GP1 rapidly and intensively developed infections by parasite WZ01. This is the first report on endoparasitic infection in oleaginous coccoid green algae. Our results will enhance understanding of parasite–host relationships, which will be beneficial in developing strategies for infection control. [ABSTRACT FROM AUTHOR]

Parasitic crustacean Dendrogaster is completely endoparasitic and is not known from any marine invertebrates other than asteroids. Understanding the diversity of this group is considerably lagging, as it is an internal parasite that is not easily detected without dissecting the host. The group is thought to have coevolved with asteroids due to its endoparasitism; however, this has not been verified due to a lack of phylogenetic studies. A molecular phylogenetic analysis was required to understand the evolution of this very specialized genus. During a biodiversity survey at An'ei Seamount established as an offshore marine protected area in Japan, we discovered an unknown species of Dendrogaster inside a recently described species of asteroids. In this study, we attempted to elucidate the phylogenetic relationships of multiple species of Dendrogaster , including a new species, Dendrogaster nike sp. nov., collected from the An'ei Seamount of the Nishi-Shichito Ridge. We determined the COI and 18S gene sequences of some Dendrogaster species and reconstructed a phylogenetic tree. Upon plotting the information of the host and habitat depth onto the phylogenetic tree, evidence of coevolution between Dendrogaster and its host, which is commonly observed in endosymbiotic organisms, was not observed. Instead, our findings suggest that species diversification in Dendrogaster may have occurred based on habitat depth rather than coevolution with the host. [ABSTRACT FROM AUTHOR]

The American marten ( Martes americana ) was reintroduced to both the Upper (UP) and northern Lower Peninsula (NLP) of Michigan during the 20th century. This is the first report of endoparasites of American marten from the NLP. Faeces from live-trapped American marten were examined for the presence of parasitic ova, and blood samples were obtained for haematocrit evaluation. The most prevalent parasites were Capillaria and Alaria species. Helminth parasites reported in American marten for the first time include Eucoleus boehmi , hookworm, and Hymenolepis and Strongyloides species. This is the first report of shedding of Sarcocystis species sporocysts in an American marten and identification of 2 coccidian parasites, Cystoisospora and Eimeria species. The pathologic and zoonotic potential of each parasite species is discussed, and previous reports of endoparasites of the American marten in North America are reviewed. [ABSTRACT FROM AUTHOR]

Prosthenorchis elegans is a member of the Phylum Acanthocephala and is an important parasite affecting New World Primates in the wild in South America and in captivity around the world. It is of significant management concern due to its pathogenicity and mode of transmission through intermediate hosts. Current diagnosis of P. elegans is based on the detection of eggs by coprological examination. However, this technique lacks both specificity and sensitivity, since eggs of most members of the genus are morphologically indistinguishable and shed intermittently, making differential diagnosis difficult, and coprological examinations are often negative in animals severely infected at death. We examined sequence variation in 633 bp of mitochondrial DNA (mtDNA) cytochrome c oxidase I (COI) sequence in 37 isolates of P. elegans from New World monkeys ( Saguinus leucopus and Cebus albifrons ) in Colombia held in rescue centers and from the wild. Intraspecific divergence ranged from 0.0 to 1.6% and was comparable with corresponding values within other species of acanthocephalans. Furthermore, comparisons of patterns of sequence divergence within the Acanthocephala suggest that Prosthenorchis represents a separate genus within the Oligacanthorhynchida. Six distinct haplotypes were identified within P. elegans which grouped into one of two well-supported mtDNA haplogroups. No association between haplogroup/haplotype, holding facility and species was found. This information will help pave the way to the development of molecular-based diagnostic tools for the detection of P. elegans as well as furthering research into the life cycle, intermediate hosts and epidemiological aspects of the species. [ABSTRACT FROM AUTHOR]

The main current concern in ruminant production is focused on sustainability. In this sense, the objective was to evaluate ruminal fermentative alterations and methane (CH4) production, as well as hematological and biochemical alterations in sheep submitted to a single mixed infection with 10,000 infective larvae (L3) of Haemonchus contortus and 30,000 L3 of Trichostrongylus colubriformis. Twenty castrated males Santa Inês sheep, seven months old averaging 30.8 ± 6.41 kg of body weight were used. Ten animals were infected, and ten animals were uninfected, in a completely randomized design. During the experimental period, blood and ruminal content samples were collected, as well as the leftovers and diet provided. Enteric methane (CH 4) production of the animals was measured at the end of the experiment. Parasitic infection affected dry matter intake, decreased red blood cell count, hemoglobin, and packed cell volume (PCV), and increased eosinophils and platelets numbers (P < 0.05). Ruminal fermentative changes were also observed, with changes in the short-chain fatty acid (SCFA) production profile, increase in propionate and decrease in acetate, and higher CH 4 production in infected animals. Thus, it is concluded that H. contortus and T. colubriformis mix infection in sheep reduces forage dry matter consumption, causes hematological changes and ruminal fermentation patterns, impairing nutritional metabolism with greater CH 4 production by infected animals. [ABSTRACT FROM AUTHOR]

Abstract: An endoparasitic copepod is reported from the urinary bladder of a fish for the first time. Endoparasitic copepods on fish hosts are extremely rare and the impact of colonization of this novel microhabitat on the biology of the parasite is discussed. This curious association was reported from two different host families of Neotropical freshwater fishes, Erythrinidae and Cichlidae, collected from the Cristalino River, a tributary of the Araguaia River, in Brazil. The copepod is fully described using light and scanning electron microscopy. Urogasilus brasiliensis n. g., n. sp. represents a new genus and species of the family Ergasilidae and can be distinguished from other genera by its unique tagmosis, in which the fourth and fifth pedigerous somites and the genital double-somite are all fused to form an elongate trunk. The anal somite is the only free abdominal somite present. The pattern of leg segmentation is also unique, with legs 1 to 3 each having a 2-segmented endopod and leg 4 reduced to a single seta. The discovery of ovigerous female ergasilids in the urinary bladder of a fish is novel and this discovery represents a good model for further studies on the adaptations to an endoparasitic lifestyle. [Copyright &y& Elsevier]

Abstract: It is unexplained how strepsipteran insects manipulate the physiology of their hosts in order to undergo endoparasitic development without being entrapped by the innate immune defences of the host. Here we present pioneering work that aimed to explore for the first time several components of the cellular and humoral immune response among immature stages of the paper wasp Polistes dominulus, in both unparasitized insects and after infection by the strepsipteran endoparasite Xenos vesparum. We carried out hemocyte counts, phagocytosis assays in vitro and antibacterial response in vivo. On the whole, hemocyte load does not seem to be drastically affected by parasitization: a non-significant increase in hemocyte numbers was observed in parasitized wasps as respect to control, while the two dominant hemocyte types were present with similar proportions in both groups. On the other hand, phagocytosis was significantly reduced in hemocytes from parasitized wasps while the antibacterial response seemed to be less effective in control. These somewhat unexpected results are discussed, along with the implications of a multiple approach in immune response studies. [Copyright &y& Elsevier]

Abstract: Females of the endoparasite Xenos vesparum (Strepsiptera, Stylopidae) may survive for months inside the host Polistes dominulus (Hymenoptera, Vespidae). The midgut structure and function in larval instars and neotenic females has been studied by light and electron microscope and by stable carbon isotopic technique. The 1st instar larva utilizes the yolk material contained in the gut lumen, whereas the subsequent larval instars are actively involved in nutrient uptake from the wasp hemolymph and storage in the adipocytes. At the end of the 4th instar, the neotenic female extrudes with its anterior region from the host; the midgut progressively degenerates following an autophagic cell death program. First the midgut epithelial cells accumulate lamellar bodies and then expel their nuclei into the gut lumen; the remnant gut consists of a thin epithelium devoid of nuclei but still provided with intercellular junctions. We fed the parasitized wasps with sugar from different sources (beet or cane), characterized by their distinctive carbon isotope compositions, and measured the bulk 13C/12C ratios of both wasps and parasites. Female parasites developing inside the wasp hemocoel are able to absorb nutrients from the host but, after their extrusion, they stop incorporating nutrients and survive thanks to the adipocytes content. [Copyright &y& Elsevier]

• A new species of endoparasitic trichodinid was first described. • The morphological characteristics and electron microscope images were provided. • The SSU rDNA data of Trichodina lishuiensis were analyzed. • The transmission route of Trichodina may takes place during the amplexus. Endoparasitic trichodinids are rather rare ciliates. In this study we describe a new species named Trichodina lishuiensis from the bladder of Odorrana schmackeri collected in Zhejiang, China, with the prevalence of 20% (9/45). We identified T. lishuiensis as a new species by morphological comparison and molecular analysis. The ciliates were observed using the dry-silver and protargol staining methods, as well as SEM (scanning electron microscopy). Trichodina lishuiensis is a small species (cell diameter 31.8-43.9 μm), with incompact denticles connection, medium-wide blades and thick rays. We also sequenced a 1712 bp-long fragment of the small subunit ribosomal RNA gene (SSU rRNA). Phylogenetic analyses showed that the new species clustered with Trichodina unionis. The route of transmission of Trichodina species in the urinary bladder remains a mystery. We hypothesize that the transmisison takes place during the amplexus, with eggs and sperm discharged from the cloaca, and that trichodinids 'accompany' the amphibian through its whole life cycle, but further studies are needed to test this hypothesis. [ABSTRACT FROM AUTHOR]

• Phosphorus restriction affected P metabolism without reducing performance. • Phosphorus restriction did not affect biochemical and hematological parameters. • Severe T. colubriformis infection impacted negatively the P metabolism of lambs. Intestinal endoparasite infection may promote a nutrient competition with host, reducing absorption and performance as consequence. Phosphorus could be more affected due to the main absorption site is the duodenum. Thus, the study measured the performance, phosphorus metabolism, bone density and blood markers in Santa Ines lambs infected Trichostrongylus colubriformis and fed with different phosphorus (P) levels were tested. Eighteen healthy six-month old, castrated male, Santa Ines lambs (initial body weight 22.4 ± 2.7 kg) were randomly assigned to 4 treatments in a 2 × 2 split-plot arrangement. Treatment factors were sufficient (SP) or deficient (DP) dietary P and uninfected (ui) or infected (i) resulting in 4 treatments: SPui, DPui, SPi, and Dpi). Five animals were assigned to each of the infected treatments and 4 to the uninfected treatments. Infection was established using a single oral dose of 40.000 T. colubriformis in the larval stage (L3). All the animals were fed Tifton 85 hay (Cynodon spp.; 60 %) supplemented with cassava and maize gluten meal (40 %). Animals were weighed and blood was sampled weekly. Body composition was estimated twice by computed tomography. P metabolism was assessed by isotope dilution after a bolus infusion of 32P (7.4 M Bq/0.5 mL). Fecal egg counts (FEC) were assessed every 3 days beginning d 18 post-infection, and adult nematodes were counted and characterized (gender, length, and eggs in reproductive tract) at slaughter. The experiment lasted 96 d, and 45 d after infeciton. Statistical procedures were performed using R studio. Infection was successful as evidenced by increased FEC, and the elevated counts were maintained longer with Dpi than SPi. Performance, feed intake, and blood parameters were not affected by treatments. Infected animals had reduced bone density and bone P concentrations as compared to uninfected ones. Endogenous P loss was reduced for DP. Plasma, saliva, and ruminal liquid P concentrations decreased in infected animals. Phosphorus absorption and retention coefficients did not differ by treatment, but the biological half-life (T 1/2) of P was reduced for infected animals due to faster blood 32P removal. We concluded that T. colubriformis infection modified P metabolism, and blood P concentrations are an indicator of animal problems, connecting infection and bone mineralization. [ABSTRACT FROM AUTHOR]

Due to the difficulties and limitations associated with field sampling of marine mammals, quantitative surveys on their parasites are still scarce in Japan. We here report the infection statuses of intestinal parasites in harbor porpoises (n = 34) and Dall's porpoises (n = 10), bycaught between 2014 and 2018 by a bottom set-net fishery in the northern part of the Nemuro Strait, Japan. Necropsies of the harbor porpoises recovered one digenean, Synthesium nipponicum , and two acanthocephalans, Corynosoma sp. and Bolbosoma sp.; no infection was observed in the Dall's porpoises. The dominant parasites were Corynosoma sp. and S. nipponicum , with a prevalence of 73.53 and 64.71% and a mean abundance of 43.88 and 7.38 individuals, respectively. Although the two porpoise-species have a sympatric distribution in this narrow strait, the findings support the existence of trophic-link dependences, which can differentially affect vulnerability to these parasites. Unlabelled Image • parasites were investigated in two porpoise species in a narrow strait. • Three parasite species were recovered from Harbor porpoises. • No infection was found in Dall's porpoises. • The differences in the infection suggest trophic-link dependences in the strait. [ABSTRACT FROM AUTHOR]

The new genus Celatogloea is proposed to accommodate a monosterigmate, heterobasidiomycetous, intrahymenial parasite of Corticium roseum, previously not distinguished from its host. The new combination Celatogloea simplicibasidium is proposed, based on Laeticorticium simplicibasidium. [Copyright &y& Elsevier]