Ascaris Suum Research Articles

Seroprevalence of Ascaris suum compared to milk spot prevalence at slaughter in Italian fattening pigs

Ascaris suum is one of the most important parasites of pigs. Apart from liver condemnation due to lesions caused by migrating larvae ("milk spots"), A. suum infections can compromise weight gain, feed conversion efficacy, as well as meat quality. The true prevalence of infection depends on the diagnostic test used and is often underestimated. We compared liver inspection at slaughter with serology, based on the recognition of a purified A. suum haemoglobin or complete homogenate of the 3rd stage larvae isolated from lungs, in nine pig farms in northern Italy. Liver lesions were found on all farms with prevalence ranging from 3.8% to 98.3%. All farms were also positive for circulating antibodies against As-Hb and As-Lung-L3, with prevalence among pigs on each farm ranging from 36.4-100% and 54.5-100%, respectively. Seroprevalence was consistently higher when compared to the prevalence of milk spots at slaughter. The higher sensitivity of the ELISA tests combined with their ease of use makes them an interesting tool to evaluate A. suum infection levels.

A molecular and morphological study of Ascaris suum in a human-pig contact scenario in northeastern Brazil.

The aim of the present study was to assess morphologic and genetic data on ascariasis in swine (Sus scrofa domesticus) and humans in low-resource rural and periurban communities in the state of Piauí, Brazil. Our cross-sectional survey included 100 fecal samples obtained from swine and 682 samples from humans. Fifteen pigs were necropsied. Human and porcine fecal samples were examined to identify Ascaris eggs. Parasites obtained in the swine necropsies were studied using scanning electron microscopy (SEM), and the mitochondrial gene encoding the cytochrome oxidase 1 (cox1) enzyme was partially amplified and sequenced for molecular taxonomy and phylogenetic analyses. The overall prevalence of Ascaris eggs in the swine fecal samples was 16/100 (16%). No Ascaris eggs were identified in the human fecal samples. SEM of six worms recovered from pigs demonstrated morphological characteristics of A. suum. Cox1 sequences were compatible with A. suum reference sequences. Original and reference (GenBank) nucleotide sequences were organized into clusters that did not segregate the parasites by host species or and region. The largest haplogroups were dominated by haplotypes H01, H02 and H31. In the communities studied, there was no epidemiological evidence of the zoonotic transmission of ascariasis at the human-swine interface.

Avaliação da eficácia da solução hidroalcoólica de própolis com glicina na redução conjunta de microrganismos e ovos de helmintos em vegetais de folhas verdes

Abstract The main goal of this study was to evaluate the effectiveness of a propolis hydroalcoholic solution with glycine on the reduction of microorganisms and helminth eggs removal in lettuce leaves. Three experimental groups were evaluated in triplicate or replicates: microbiological (ME), parasitological (PE), and microbiological and parasitological (MPE). Before the experiments, the initial concentration of the native microbiota was assessed by counting mesophilic aerobes, molds and yeasts, using conventional microbiological techniques. Lettuce leaves were washed in tap water and subjected to different immersion treatments: propolis hydroalcoholic solution (PHS), propolis hydroalcoholic solution at pH 5.5 (PHS2), and propolis hydroalcoholic solution with glycine (PHS-glycine). In ME, propolis hydroalcoholic solution combined or not with glycine, was evaluated on the reduction of native microbiota. Residual microbiological contamination was assessed. In the PE, the effect of PHS2 and PHS-glycine was evaluated on the removal of a known number of Ascaris suum eggs on leaves artificially contaminated. In MPE, PHS-glycine was evaluated on the reduction of native microbiota and removal of eggs. A reduction of more than 2 log CFU/g was observed in ME. In PE, PHS-glycine removed 37.22% of eggs. In MPE, the PHS-glycine reduced 3.3 CFU/g of mesophilic aerobes, 5.0 log CFU/g of fungi, and 35.53% of eggs from vegetables. The results highlighted the solution’s efficiency in reducing or eliminating different contaminants in vegetables and reinforced the need for the development of hygiene methods that do not harm human health and are reproducible at the household level.

Comparison of McMaster and Mini-FLOTAC techniques for the diagnosis of internal parasites in pigs.

This purpose of this study was to compare the efficiency of the McMaster and Mini-FLOTAC quantitative techniques in the investigation of helminths in feces of pigs. An analysis was made of 74 fecal samples from pigs raised on family farms located in Rio de Janeiro, Brazil. These were analyzed by the Mini-FLOTAC and McMaster techniques in a solution of 1,200g/mL NaCl. This investigation revealed a superiority in the frequency of all helminths detected by Mini-FLOTAC, including Ascaris suum, Trichuris suis, strongyles and Strongyloides ransomi. The Kappa index revealed substantial agreement in all comparisons made in relation to the frequency of positive samples. However, significant statistical differences in the comparison of EPGs between McMaster and Mini-FLOTAC were observed for all nematodes (p ≤0.05). Higher values of Pearson's linear correlation coefficient (r), between the techniques in relation to EPG were observed for A. suum and T. suis, differently from what was observed for strongyles and S. ransomi. Mini-FLOTAC proved to be a more satisfactory and reliable technique both for the diagnosis of parasites and for the determination of EPG in pig feces due to the larger size of its counting chambers, thus increasing the helminth egg recovery rates.

EPIZOOTIOLOGICAL AND CLINICAL SIGNIFICANCE OF STEPHANURUS DENTATUS NEMATODE IN SWINE

Stephanuriosis is a disease of the urinary tract of both domestic pigs and wild boars occurring in tropical and subtropical regions, with a tendency to spread to other geographical areas. In endemic areas, the disease occurs more often in extensively bred herds, normally with nonspecific clinical picture. As a result of larval stage migrations and parasitism of adult forms of nematode Stephanurus dentatus, the damage occurs in the liver, kidneys, ureters, lungs, pancreas and perirenal adipose tissue. Damage to the liver is reminiscent of lesions caused by Ascaris suum, which is of particular clinical significance for differential diagnosis of parasitic swine diseases. Stephanurus dentatus is of great economic importance due to direct and indirect damage it causes. Infected animals delay in reaching market weight, their meat is declared unfit for consumption, and they are sent to forced slaughter. Examinations of potential presence of this parasite in Serbia should include populations of wild boars and domestic pigs from extensive traditional breeding outdoors. After intense climate changes that have occurred in recent decades, and also due to the possibility of importing infected animals from endemic areas, the proposed research would have both epizootiological and clinical significance

Guts within guts: the microbiome of the intestinal helminth parasite Ascaris suum is derived but distinct from its host

BackgroundIntestinal helminths are extremely prevalent among humans and animals. In particular, intestinal roundworms affect more than 1 billion people around the globe and are a major issue in animal husbandry. These pathogens live in intimate contact with the host gut microbiota and harbor bacteria within their own intestines. Knowledge of the bacterial host microbiome at the site of infection is limited, and data on the parasite microbiome is, to the best of our knowledge, non-existent.ResultsThe intestinal microbiome of the natural parasite and zoonotic macropathogen, Ascaris suum was analyzed in contrast to the diversity and composition of the infected host gut. 16S sequencing of the parasite intestine and host intestinal compartments showed that the parasite gut has a significantly less diverse microbiome than its host, and the host gut exhibits a reduced microbiome diversity at the site of parasite infection in the jejunum. While the host’s microbiome composition at the site of infection significantly determines the microbiome composition of its parasite, microbial signatures differentiate the nematodes from their hosts as the Ascaris intestine supports the growth of microbes that are otherwise under-represented in the host gut.ConclusionOur data clearly indicate that a nematode infection reduces the microbiome diversity of the host gut, and that the nematode gut represents a selective bacterial niche harboring bacteria that are derived but distinct from the host gut.2jWY34QGXgkVDDF3YbbM2YVideo

Uji Aktivitas Ekstrak Daun Akasia (Acacia Auriculiformis) Sebagai Antihelmintik Terhadap Cacing Ascaris Suum

Ascariasis in pigs is a worm disease caused by Ascaris suum worms. These worms can cause a lot of losses that will have an impact on the production and growth of pigs. Control and treatment of Ascaris suum worms can be giving modern anthelmintics. However, the use of modern anthelmintics can have a negative impact. For that we need other alternative with herbal treatment using plants that have secondary metabolite compounds that are efficacious as anthelmintics such as acacia plants (Acacia auriculiformis). This study aimed to determine the effectiveness of extract leaves of acacia (Acacia auriculiformis) as anthelmintic against Ascaris suum worms and to determine the LC50 and LT50 values of extract leaves of acacia (Acacia auriculiformis). This research was conducted from July to August 2021. The sample of worms used was 105 tails for 3 replications using 7 groups consisting of 5 treatment groups test extract leaves of acacia (Acacia auriculiformis) concentrations of 5%, 10%, 15%, 20%, 25% and 2 control groups. The research data were analyzed using the Kruskal Wallis, Mann Whitney and probit analysis test. The results showed that within 7 hours of testing extract leaves of akasia (Acacia auriculiformis) was able to kill Ascaris suum worms at concentrations of 15%, 20% and 25% with LC50 value is 24.876% and LT50 is 7.083 hours.

Intestinal roundworm infection in organic and alternative swine farms in the USA

Swine parasites are a challenge for organic and alternative pig farmers and represent suboptimal animal health because use of chemical prophylaxis is not recommended. There is no comprehensive study of how prevalent gastrointestinal parasites are in organic or alternative pig farms across the USA. This study investigates prevalence, abundance, and intensity measures for three intestinal roundworm parasites (Ascaris suum, Oesophagostomum spp. and Trichuris suis) on organic and alternative swine farms by quantifying their eggs in pig feces, pastured soil, and bedding. Nine farms raising pigs in bedded facilities across four states (Iowa, Minnesota, Pennsylvania, and Wisconsin) were sampled, and analysis of parasite egg counts from feces indicate that 88.9%, 55.5%, and 44.4% of farms were infected with A. suum, Oesophagostomum spp. and T. suis, respectively. Prevalence, mean abundance, and mean intensity of eggs per gram (EPG) in feces for A. suum and T. suis were higher in growing and finishing pigs, whereas they were higher for Oesophagostomum spp. in finishing pigs and sows. Prevalence and abundance with A. suum eggs in feces were higher in organic certified farms, whereas abundance of Oesophagostomum spp. and T. suis was lower than those in alternative farms. Fewer eggs were recovered from soils than bedding samples, but their presence in both substrates confirmed that dispersal stages occur in farms. Overall, our results indicate that intestinal parasite infection across organic and alternative swine farms in the USA is common, and not surprising given that few options to control infection within organic regulations are available.

Diethylcarbamazine, TRP channels and Ca2+ signaling in cells of the Ascaris intestine.

The nematode parasite intestine absorbs nutrients, is involved in innate immunity, can metabolize xenobiotics and as we show here, is also a site of action of the anthelmintic, diethylcarbamazine. Diethylcarbamazine (DEC) is used to treat lymphatic filariasis and activates TRP-2, GON-2 & CED-11 TRP channels in Brugia malayi muscle cells producing spastic paralysis. DEC also has stimulatory effects on ascarid nematode parasites. Using PCR techniques, we detected, in Ascaris suum intestine, message for: Asu-trp-2, Asu-gon-2, Asu-ced-11, Asu-ocr-1, Asu-osm-9 and Asu-trpa-1. Comparison of amino-acid sequences of the TRP channels of B. malayi, and A. suum revealed noteworthy similarity, suggesting that the intestine of Ascaris will also be sensitive to DEC. We used Fluo-3AM as a Ca2+ indicator and observed characteristic unsteady time-dependent increases in the Ca2+ signal in the intestine in response to DEC. Application of La3+ and the TRP channel inhibitors, 2-APB or SKF 96365, inhibited DEC mediated increases in intracellular Ca2+. These observations are important because they emphasize that the nematode intestine, in addition to muscle, is a site of action of DEC as well as other anthelmintics. DEC may also enhance the Ca2+ toxicity effects of other anthelmintics acting on the intestine or, increase the effects of other anthelmintics that are metabolized and excreted by the nematode intestine.

ENDOPARASITES OF VIETNAMESE BELLIED PIGS IN THE PASTURE GROWING SYSTEM IN FARMS OF THE ODESA REGION

The article provides data on the spread of endoparasitoses in vietnamese bellied pigs in the pasture growing system in the farms of the Odesa region. Pigs can have numerous intestinal parasites, most often protozoa and nematodes. Although the course of such parasitic infections is usually subclinical, clinical manifestations may occasionally occur, especially in growing pigs. The study of the structure and functioning of parasitic systems is extremely important. The obtained data on gastrointestinal parasites in pigs can help in the development of effective and sustainable measures for the prevention of pig diseases.
 The aim of the work was to monitor endoparasitoses in vietnamese bellied pigs in the pasture growing system, depending on age, in the farms of the Odesa region.
 A total of 475 samples of feces of vietnamese bellied pigs from 6 private farms of Odesa region were studied. Fecal samples were collected from suckling piglets and weanling piglets (<4 months), young (4‒8 months) and adults (>8 months) of both sexes.
 It was established that the total infestation with protozoa in piglets < 4 months. age was 86.7 %, in growing pigs (4-8 months) ‒ 28.9 %, and in adults ‒ 18.7 %, helminthes infestation was 13.3 %, 71.1% and 81.3% in accordance. Piglets < 4 months. age, Isospora suis (28.3 %) and Eimeria suis (18.6 %) were most infested, while Strongyloides sp. (2.7 %).
 Ascaris suum (33.4 %) and Trichuris suis (24.6 %) had the highest lesion extent in growing pigs (4‒8 months), and the lowest among protozoans was Isospora suis and Blastocystis sp. (2.9 %). In adult pigs, the highest infestation of Ascaris suum (34.4 %) and Trichuris suis (31.2 %) was recorded, while isosporosis and cryptosporidiosis were not recorded.

Parasite cenoces of the wild pig (<i>Sus scrofa</i>) on the Trans-Baikal Territory

A comprehensive veterinary study of the wild pig population on the territory of the Trans-Baikal Territory for helminthiasis and microbial transmission was carried out. The helminth fauna of wild pigs was studied and the circulation of bacterial pathogens in the population of these animals was established. The object of the research were materials obtained in the field studies on the Trans-Baikal Territory districts. The study of endoparasite infestation was conducted in 37 wild pigs aged 6 months to 3 years during 2019-2021. Infestation of wild pigs with eight different types of helminths was registered on the Trans-Baikal Territory. The maximum extent of infestation (32.4%) was recorded in Setaria labiato-papillosa. Wild pigs are infected with both imaginal helminths Setaria labiato-papillosa, Metastrongylus elongatus, Ascaris suum, Trichocephalus suis, Oesophagostomum dentatum, as well as with helminth larvae Cysticercus tenuicollis and Cysticercus cellulosae. The study of the morphology of sexually mature pathogens indicates parasitization of helminths of the genus Setaria labiato-papillosa in pigs. Out of 37 wild pigs studied, the association infestation of setariosis + ascaridosis was recorded in 12 animals, three pigs were simultaneously parasitized by ascaridosis + trichocephalus, and two animals had the association of setariosis + metastrongylosis.Organoleptic examination of carcasses of pigs affected by associative infestation showed a 2-fold or more reduction in the thickness of the backbone and side fat in comparison with helminth-free animals. In pigs infected with ascaridosis and metastrongylosis, microbial cultures of S. typhimurium and E. rhusiopathiae were isolated from paraenchymatous organs. Parasite ecosystems with different types of helminths and helminths + highly pathogenic bacteria have been recorded in the body of wild pigs.

Prevalence of Gastrointestinal Helminthes in Pigs Reared in Research Farms of Michael Okpara University of Agriculture, Umudike, South Eastern Nigeria

Gastrointestinal parasitism in swine production is a world-wide problem especially in tropical resource-poor countries. These infections in animals result in significant economic losses. This study aimed to assess the prevalence and spectrum of gastrointestinal parasites of pigs reared in two research farms in Michael Okpara University of Agriculture, Umudike, South eastern Nigeria. From April, 2016 to July, 2016, 220 samples of pig faeces from two research farms (CASAP Research Farm and MOUAU Commercial Pig Farm) were analyzed using floatation and direct smear methods to identify varied parasitic stages present in the faeces. Data generated showed an overall prevalence of 64.6% (142/220) in the two farms. Five parasite species made up of four Nematode and one Cestode were observed namely Ascaris suum (26.4%), Trichuris suis (26.4%), Strongyloides spp (21.9%), Oesophagostomum dentatum (20.0%) and Pseudanoplocephala spp. (5.6%). Mixed infections were also observed. Those within the ages of 0-8months had the highest prevalence (74.12%). Further, 67.42% male pigs and 62.60% of female pigs were found to be infected with one or the other endoparasite revealing a high prevalence of parasitic problems within Umudike. It is recommended that pigs should be treated regularly to prevent or reduce infection to the barest minimal level.

Modulation of the porcine intestinal microbiota in the course of Ascaris suum infection

BackgroundThe porcine roundworm Ascaris suum impairs feed conversion and weight gain, but its effects on intestinal microbiota remain largely unexplored.MethodsModulation of the intestinal microbiota was assessed in pigs that were infected once with 10,000 A. suum eggs and pigs that received a trickle infection (1000 eggs/day over 10 days), compared with a non-infected control group. Six pigs each were sacrificed per group at days 21, 35 and 49 post-infection (p.i.). Faecal samples taken weekly until slaughter and ingesta samples from different intestinal compartments were subjected to next-generation sequencing of the bacterial 16S rRNA gene.ResultsThe results revealed marked differences between the single- and the trickle-infected group. Single infection caused a remarkable but transient decrease in microbial diversity in the caecum, which was not observed in the trickle-infected group. However, an increase in short-chain fatty acid-producing genera in the caecum on day 21 p.i., which shifted to a decrease on day 35 p.i., was common to both groups, possibly related to changes in excretory–secretory products following the parasite’s final moult. Faecal microbial interaction networks were more similar between the single-infected and control group than the trickle-infected group. In addition, a lower degree of similarity over time indicated that A. suum trickle infection prevented microbiota stabilization.ConclusionsThese different patterns may have important implications regarding the comparability of experimental infections with natural scenarios characterized by continuous exposure, and should be confirmed by further studies.Graphical

Reconstitution of an N-AChR from Brugia malayi, an evolved change in acetylcholine receptor accessory protein requirements in filarial parasites.

Neurotransmission is an important target for anthelmintic drugs, where receptor characteristics and response can be examined through reconstitution ex vivo in Xenopus laevis oocytes. The homomeric ACR-16 nicotine sensitive acetylcholine receptors (N-AChRs) of several helminth species have been characterized in this way. Our efforts to reconstitute the N-AChR from the clade III filarial parasite, Brugia malayi using similar conditions, initially produced no detectable response. A robust response to acetylcholine is obtained from the closely related clade III parasite Ascaris suum, suggesting that specific changes have occurred between Ascaris and Brugia. N-AChRs from three species intermediate between A. suum and B. malayi were characterized to provide information on the cause. Maximal response to acetylcholine did not change abruptly, consistent with a discrete event, but rather decreased progressively from A. suum through Dracunculus medinensis, Gonglylonema pulchrum and Thelazia callipaeda. Receptor responses to the characteristic nicotine, and other agonists were generally similar. The decrease in maximal current did correlate with a delayed time to reach larger response. Together, this suggested that the failure to reconstitute the B. malayi N-AChR was one extreme of a progressive decrease and that an issue with synthesis of the receptor in oocytes was responsible. Addition of accessory proteins EMC-6, NRA-2 and NRA-4, in addition to RIC-3, produced a small, but measurable B. malayi N-AChR response. Pharmacological properties of a chimeric B. malayi N-AChR were equivalent to the other species, confirming the receptor response remains unchanged while its production is increasingly dependent on accessory proteins. One possibility is that loss of many subunits for acetylcholine receptors from the filarial nematode genome is linked to new subunit combinations that lead to such a dependence. This novel phylogenetic approach allowed the first characterization of a B. malayi AChR ex vivo and in doing so, provides a framework for the successful characterization of other receptors that have yet to be reconstituted.

Ascaris suum excretory/secretory products differentially modulate porcine dendritic cell subsets.

Helminths produce excretory/secretory products (E/S) which can modulate the immune responses of their hosts. Dendritic cells (DC) are essential for initiating the host T cell response and are thus potential targets for modulation by helminth E/S. Here we study immunomodulation of porcine peripheral blood DC subsets following ex vivo stimulation with E/S from Ascaris suum, a common helminth of pigs with considerable public health and economic importance. Our data showed that the relative frequencies of DC subsets in porcine blood differ, with plasmacytoid DC (pDC) being the most prominent in healthy 6-month-old pigs. pDC are an important cytokine source, and we found that A. suum E/S suppressed production of the type 1 cytokines IL-12p40 and TNF-α by this subset following toll-like receptor (TLR) ligation. In contrast, conventional DC (cDC) are more efficient antigen presenters, and the expression of CD80/86, costimulatory molecules essential for efficient antigen presentation, were modulated differentially by A. suum E/S between cDC subsets. CD80/86 expression by type 1 cDC (cDC1) following TLR ligation was greatly suppressed by the addition of A. suum E/S, while CD80/86 expression by type 2 cDC (cDC2) was upregulated by A. suum E/S. Further, we found that IFN-γ production by natural killer (NK) cells following IL-12 and IL-18 stimulation was suppressed by A. suum E/S. Finally, in the presence of E/S, IFN-γ production by CD4+ T cells co-cultured with autologous blood-derived DC was significantly impaired. Together, these data provide a coherent picture regarding the regulation of type 1 responses by A. suum E/S. Responsiveness of pDC and cDC1 to microbial ligands is reduced in the presence of E/S, effector functions of Th1 cells are impaired, and cytokine-driven IFN-γ release by NK cells is limited.

A reverse vaccinology approach identifies putative vaccination targets in the zoonotic nematode Ascaris.

Ascariasis is the most prevalent helminthic disease affecting both humans and pigs and is caused by the roundworms Ascaris lumbricoides and Ascaris suum. While preventive chemotherapy continues to be the most common control method, recent reports of anthelminthic resistance highlight the need for development of a vaccine against ascariasis. The aim of this study was to use a reverse vaccinology approach to identify potential vaccine candidates for Ascaris. Three Ascaris proteomes predicted from whole-genome sequences were analyzed. Candidate proteins were identified using open-access bioinformatic tools (e.g., Vacceed, VaxiJen, Bepipred 2.0) which test for different characteristics such as sub-cellular location, T-cell and B-cell molecular binding, antigenicity, allergenicity and phylogenetic relationship with other nematode proteins. From over 100,000 protein sequences analyzed, four transmembrane proteins were predicted to be non-allergen antigens and potential vaccine candidates. The four proteins are a Piezo protein, two voltage-dependent calcium channels and a protocadherin-like protein, are all expressed in either the muscle or ovaries of both Ascaris species, and all contained high affinity epitopes for T-cells and B-cells. The use of a reverse vaccinology approach allowed the prediction of four new potential vaccination targets against ascariasis in humans and pigs. These targets can now be further tested in in vitro and in vivo assays to prove efficacy in both pigs and humans.

Identification and characterization of epicuticular proteins of nematodes sharing motifs with cuticular proteins of arthropods.

Specific collagens and insoluble proteins called cuticlins are major constituents of the nematode cuticles. The epicuticle, which forms the outermost electron-dense layer of the cuticle, is composed of another category of insoluble proteins called epicuticlins. It is distinct from the insoluble cuticlins localized in the cortical layer and the fibrous ribbon underneath lateral alae. Our objective was to identify and characterize genes and their encoded proteins forming the epicuticle. The combination between previously obtained laboratory results and recently made available data through the whole-genome shotgun contigs (WGS) and the transcriptome Shotgun Assembly (TSA) sequencing projects of Ascaris suum allowed us to identify the first epicuticlin gene, Asu-epic-1, on the chromosome VI. This gene is formed of exon1 (55 bp) and exon2 (1067 bp), separated by an intron of 1593 bp. Exon 2 is formed of tandem repeats (TR) whose number varies in different cDNA and genomic clones of Asu-epic-1. These variations could be due to slippage of the polymerases during DNA replication and RNA transcription leading to insertions and deletions (Indels). The deduced protein, Asu-EPIC-1, consists of a signal peptide of 20 amino acids followed by 353 amino acids composed of seven TR of 49 or 51 amino acids each. Three highly conserved tyrosine motifs characterize each repeat. The GYR motif is the Pfam motif PF02756 present in several cuticular proteins of arthropods. Asu-EPIC-1 is an intrinsically disordered protein (IDP) containing seven predicted molecular recognition features (MoRFs). This type of protein undergoes a disorder-to-order transition upon binding protein partners. Three epicuticular sequences have been identified in A. suum, Ascaris lumbricoides, and Toxocara canis. Homologous epicuticular proteins were identified in over 50 other nematode species. The potential of this new category of proteins in forming the nematode cuticle through covalent interactions with other cuticular components, particularly with collagens, is discussed. Their localization in the outermost layer of the nematode body and their unique structure render them crucial candidates for biochemical and molecular interaction studies and targets for new biotechnological and biomedical applications.

NHR-23 and SPE-44 regulate distinct sets of genes during Caenorhabditis elegans spermatogenesis.

Spermatogenesis is the process through which mature male gametes are formed and is necessary for the transmission of genetic information. While much work has established how sperm fate is promoted and maintained, less is known about how the sperm morphogenesis program is executed. We previously identified a novel role for the nuclear hormone receptor transcription factor, NHR-23, in promoting Caenorhabditis elegans spermatogenesis. The depletion of NHR-23 along with SPE-44, another transcription factor that promotes spermatogenesis, caused additive phenotypes. Through RNA-seq, we determined that NHR-23 and SPE-44 regulate distinct sets of genes. The depletion of both NHR-23 and SPE-44 produced yet another set of differentially regulated genes. NHR-23-regulated genes are enriched in phosphatases, consistent with the switch from genome quiescence to post-translational regulation in spermatids. In the parasitic nematode Ascaris suum, MFP1 and MFP2 control the polymerization of Major Sperm Protein, the molecule that drives sperm motility and serves as a signal to promote ovulation. NHR-23 and SPE-44 regulate several MFP2 paralogs, and NHR-23 depletion from the male germline caused defective localization of MSD/MFP1 and NSPH-2/MFP2. Although NHR-23 and SPE-44 do not transcriptionally regulate the casein kinase gene spe-6, a key regulator of sperm development, SPE-6 protein is lost following NHR-23+SPE-44 depletion. Together, these experiments provide the first mechanistic insight into how NHR-23 promotes spermatogenesis and an entry point to understanding the synthetic genetic interaction between nhr-23 and spe-44.

The Effects of Allium sativum L., Artemisia absinthium L., Cucurbita pepo L., Coriandrum sativum L., Satureja hortensis L. and Calendula officinalis L. on the Embryogenesis of Ascaris suum Eggs during an In Vitro Experimental Study.

Ascaris suum is present in traditionally managed indoor pig herds and in industrialized farms, especially in older fatteners and sows. The increasing resistance to common antihelminthic drugs redirected research towards alternative and traditional therapies, which also include medicinal plants. This study comparatively evaluated the in vitro antiparasitic effects of Allium sativum L., Artemisia absinthium L., Cucurbita pepo L., Coriandrum sativum L., Satureja hortensis L. and Calendula officinalis L. against A. suum egg hatching and larval development. A. suum eggs were sampled from randomized fecal specimens collected from traditionally raised swine. The egg suspension (ES, 12 × 103/mL) was divided into two controls (C) (1C—1 mL ES + 1 mL distilled water, 2C—five plates of 1 mL ES + 1 mL ethanol of 70%, 35%, 17.5%, 8.75%, and 4.375%, respectively) and six experimental groups, and placed in 3 mL cell plates. The experimental groups (EG, 1–6) included ES + each alcoholic plant extract (10%, 5%, 2.5%, 1.25%, 0.625%). Both C and EG were performed in quintuplicate. All variants were incubated at 27 °C for a total of 21 days. A. suum eggs were examined after 2, 14 (L1), and 21 (L2/L3) days of incubation. The efficacy of all tested plant extracts increased with concentration. Anti-embryogenic effects on A. suum eggs were expressed by all plants. A superior influence was observed in A. sativum L., A. absinthium L., C. pepo L. and S. hortensis L. extracts, at all concentrations tested. A. sativum L. and A. absinthium L. extracts showed the strongest antihelminthic activity, while C. sativum L. and C. officinalis L. were the weakest ascaricids. Future in-depth phytochemical studies are required to identify the compounds responsible for the anthelminthic properties of these plant species.

Bioaccessibility and oral immunization efficacy of a chimeric protein vaccine against Ascaris suum

Human ascariasis has been characterized as the most prevalent neglected tropical disease worldwide. There is an urgent need for search to alternative prevention and control methods for ascariasis. Here we aimed to establish a protocol of oral immunization with a previously described chimera protein capable of resist through digestion and induce mucous protection against Ascaris suum infection. Mice were oral immunized with seven doses with one day interval and challenged with A. suum ten days after the last dose. In vitro digestion showed that 64% of chimeric protein was bioaccessible for absorption after digestion. Immunized mice display 66,2% reduction of larval burden in lungs compared to control group. In conclusion we demonstrated that oral immunization with chimera protein protects the host against A. suum larval migration leading to less pronounced histopathological lesions.