Search

Background: Coccidiosis caused by Eimeria stiedae is a widespread and economically significant disease of rabbits. The lack of studies on the life-cycle development and host interactions of E. stiedae at the molecular level has hampered our understanding of its pathogenesis., Methods: In this study, we present a comprehensive transcriptome landscape of E. stiedae to illustrate its dynamic development from unsporulated oocysts to sporulated oocysts, merozoites, and gametocytes, and to identify genes related to parasite-host interactions during parasitism using combined PacBio single-molecule real-time and Illumina RNA sequencing followed by bioinformatics analysis and qRT-PCR validation., Results: In total, 12,582 non-redundant full-length transcripts were generated with an average length of 1808 bp from the life-cycle stages of E. stiedae. Pairwise comparisons between stages revealed 8775 differentially expressed genes (DEGs) showing highly significant description changes, which compiled a snapshot of the mechanisms underlining asexual and sexual biology of E. stiedae including oocyst sporulation between unsporulated and sporulated oocysts; merozoite replication between sporulated oocysts and merozoites; and gametophyte development and gamete generation between merozoites and gametocytes. Further, 248 DEGs were grouped into nine series clusters and five groups by expression patterns, and showed that parasite-host interaction-related genes predominated in merozoites and gametocytes and were mostly involved in steroid biosynthesis and lipid metabolism and carboxylic acid. Additionally, co-expression analyses identified genes associated with development and host invasion in unsporulated and sporulated oocysts and immune interactions during gametocyte parasitism., Conclusions: This is the first study, to our knowledge, to use the global transcriptome profiles to decipher molecular changes across the E. stiedae life cycle, and these results not only provide important information for the molecular characterization of E. stiedae, but also offer valuable resources to study other apicomplexan parasites with veterinary and public significance.

Background: Scabies is caused by Sarcoptes scabiei burrowing into the stratum corneum of the host's skin and is detrimental to the health of humans and animals. Vaccines are an attractive alternative to replace the acaricides currently used in their control., Methods: In the present study, the S. scabiei chitinase-like protein 5 (SsCLP5) was characterized and recombinant SsCLP5 (rSsCLP5) was evaluated as a candidate vaccine protein for anti-mite protection in rabbits. The expression, characterization and immunolocalization of SsCLP5 were examined. Vaccination experiments were performed on three test groups (n = 12 per group) immunized with purified rSsCLP5. Control groups (n = 12 per group) were immunized with PBS, QuilA saponin or empty vector protein. After challenge, the inflammatory reaction and skin lesions were graded and rSsCLP5 indirect ELISA was used to detect antibody IgG levels in serum samples at the time of vaccination and post-challenge., Results: The results showed that rSsCLP5 had high immunoreactivity and immunogenicity. In S. scabiei, SsCLP5 had a wide distribution in the chewing mouthpart, legs and exoskeleton, especially the outer layer of the exoskeleton. Vaccination with rSsCLP5 resulted in 74.3% (26/35) of rabbits showing no detectable lesions after challenge with S. scabiei., Conclusions: Our data demonstrate that rSsCLP5 is a promising candidate for a recombinant protein-based vaccine against S. scabiei. This study also provides a method for studying scabies vaccine using rabbit as an animal model and a basis for screening more effective candidate proteins.

Cysticercosis, caused by the larvae of Taenia pisiformis, is a common disease in rabbits that results in economic losses. To date, there has been limited information available on the early detection of infection by this parasite. This study describes a dot-ELISA method based on an autologous antigen annexin B1 (Tpanxb1). Its potential for serodiagnosis of rabbit cysticercosis was also evaluated. Western blot analysis revealed that the recombinant Tpanxb1 (rTpanxb1) protein could be specifically recognized by rabbit anti-sera. In serum trials, the antibodies could be detected by dot-ELISA using rTpanxb1 at 14 days post-infection. The positive response was present for up to 49 days post-infection. Based on the necropsy results of 169 rabbit samples, the relative sensitivity and specificity of the dot-ELISA were 94.55% and 92.86%, respectively. This study provides a foundation for studying the immunological function of annexin and its application to control Taenia cestodes.

Background: Scabies caused by Sarcoptes scabiei is a widespread but a neglected tropical zoonosis. In this study, we characterised a S. scabiei thioredoxin peroxidase (SsTPx) and evaluated a recombinant SsTPx as a diagnostic antigen in rabbits., Methods: The open reading frame of the gene encoding SsTPx-2 was amplified and the recombinant protein was expressed in Escherichia coli cells and purified. SsTPx was localized in mite tissue by immunolocalisation using the purified recombinant protein. Serodiagnosis assays were carried out in 203 New Zealand White rabbit serum samples by dot-ELISA., Result: The open reading frame (489 bp) of the gene encodes an 18.11 kDa protein, which showed highly homology to that of Psoroptes cuniculi (98.77% identity) and belongs to the 2-Cys family of peroxiredoxins. SsTPx was mainly distributed in muscle tissues of mites, integument of the epidermis and the anterior end of S. scabiei. Although SsTPx cross-reactivity with psoroptic mites was observed, the SsTPx dot-ELISA showed excellent diagnostic ability, with 95.3% sensitivity and 93.8% specificity in mange-infected and uninfected groups., Conclusions: This study showed that the purified SsTPx is a highly sensitive antigen for the diagnosis of mange infection by dot-ELISA. This technique is a rapid and convenient method that can be used worldwide for the clinical diagnosis of sarcoptic mange in rabbits, and is especially useful in developing regions.

The larval stage of Taenia pisiformis, also known as Cysticercus pisiformis, is the causative agent of cysticercosis and the cause of severe health problems in rabbits that negatively impacts on husbandry production. To date, there is no fast detection method to identify early infections in rabbits. In the present study, a new dot-ELISA-based on an endogenous antigen fatty acid-binding protein (FABP) was developed for the detection of cysticercosis, and its potential was then evaluated using test serum samples. Immunolocalisation showed that T. pisiformis FABP (TpFABP) localised to the parenchyma of the bladder wall of the cysticercus and perinuclear cytoplasm of parenchyma of the adult parasite. After cloning and expression, recombinant TpFABP (rTpFABP) protein was used for serodiagnosis of T. pisiformis infection in rabbits by dot-ELISA. The antibody was detected 14 days post-infection in rabbits experimentally infected with T. pisiformis. Based on the necropsy results, the sensitivity and specificity of 169 serum samples tested by rTpFABP dot-ELISA were found to be 98.2% (54/55) and 92.1% (105/114), respectively. These data suggest that the dot-ELISA developed in this study has potential for detection of T. pisiformis infection in rabbits., (© D. Yang et al., published by EDP Sciences, 2013.)

Sarcoptes scabiei (S. scabiei) is an ectoparasite that can infest humans and 150 mammalian host species, primarily causing pruritus, crust, and alopecia. However, neither the pathological process of host skin under S. scabiei infection nor the mechanism of S. scabiei infection in regulating apoptosis and keratinization of host skin has been studied yet. In this study, a total of 56 rabbits were artificially infested with S. scabiei, and the skin samples were collected at seven different time points, including 6 h, 12 h, day 1, day 3, 1 week, 4 weeks, and 8 weeks, whereas a group of eight rabbits served as controls. We measured epidermal thickness by H&E staining, observed the skin ultrastructure by electron microscopy, and detected the degree of skin apoptosis by TUNEL staining. The level of transcription of genes related to apoptosis and keratinization was detected by quantitative real-time PCR (qRT-PCR), and the level of Bcl-2 protein expression was further detected using immunohistochemistry. Our results showed that, with increased infestation time, the epidermal layer of the rabbit skin exhibited significant thickening and keratinization, swollen mitochondria in the epidermal cells, and increased skin apoptosis. The level of caspase-1, 3, 8, 10, 14, and Bcl-2 mRNA expression was increased, whereas the level of keratin 1 and 5 was decreased after S. scabiei infestation. In conclusion, S. scabiei infestation causes thickening of the epidermis, which may be related to apoptosis-induced proliferation and skin keratinization. [ABSTRACT FROM AUTHOR]

Eimeria magna is a common pathogen in rabbits, which results in lethargy, weight loss, diarrhea, and even death in severe cases after infection. The current method for preventing rabbit coccidiosis is to add anticoccidial drugs to the diet. However, there are many concerns about drug resistance and drug residues. In our study, the rEmMIC2 and rEmMIC3 proteins were cloned and expressed to evaluate potential as recombinant subunit vaccine candidate antigens. The protective effects of rEmMIC2 and rEmMIC3 were evaluated by the relative weight gain ratio, oocyst decrease rate, anticoccidial index, feed conversion ratio, pathological alterations, clinical symptoms, specific IgG antibody, and cytokine levels in rabbits. The molecular weights of rEmMIC2 and rEmMIC3 were 18.69 kDa and 17.47 kDa, respectively. After the coccidia challenge, the control groups showed anorexia and soft poop, whereas the experimental group showed few anorexia symptoms. Significantly different from the control group, the relative weight gain ratios of the immunized rEmMIC2 and rEmMIC3 groups were 78.37% and 75.29%, respectively, and the oocyst reduction was 77.95% and 76.09%, respectively, and the anticoccidial index was 171.12 and 169.29, respectively. IgG antibody, IFN-γ, IL-4, IL-10, and IL-17 levels were significantly increased in the experimental group. The results showed that rEmMIC2 and rEmMIC3 have potential as vaccine candidate antigens. [ABSTRACT FROM AUTHOR]

Background: Eimeria stiedae parasitizes the bile duct, causing hepatic coccidiosis in rabbits. Coccidiosis control using anticoccidials led to drug resistance and residues; therefore, vaccines are required as an alternative control strategy. Apical membrane antigen 1 (AMA1) and immune mapped protein 1 (IMP1) are surface-located proteins that might contribute to host cell invasion, having potential as candidate vaccine antigens. Methods: Herein, we cloned and expressed the E. stiedae EsAMA1 and EsIMP1 genes. The reactogenicity of recombinant AMA1 (rEsAMA1) and IMP1 (rEsIMP1) proteins were investigated using immunoblotting. For the vaccination-infection trial, rabbits were vaccinated with rEsAMA1 and rEsIMP1 (both 100 μg/rabbit) twice at 2-week intervals. After vaccination, various serum cytokines were measured. The protective effects of rEsAMA1 and rEsIMP1 against E. stiedae infection were assessed using several indicators. Sera were collected weekly to detect the specific antibody levels. Results: Both rEsAMA1 and rEsIMP1 showed strong reactogenicity. Rabbits vaccinated with rEsAMA1 and rEsIMP1 displayed significantly increased serum IL-2 (F(4, 25) = 9.53, P = 0.000), IL-4 (F(4, 25) = 7.81, P = 0.000), IL-17 (F(4, 25) = 8.55, P = 0.000), and IFN-γ (F(4, 25) = 6.89, P = 0.001) levels; in the rEsIMP1 group, serum TGF-β1 level was also elevated (F(4, 25) = 3.01, P = 0.037). After vaccination, the specific antibody levels increased and were maintained at a high level. The vaccination-infection trial showed that compared with the positive control groups, rabbits vaccinated with the recombinant proteins showed significantly reduced oocyst output (F(5, 54) = 187.87, P = 0.000), liver index (F(5, 54) = 37.52, P = 0.000), and feed conversion ratio; body weight gain was significantly improved (F(5, 54) = 28.82, P = 0.000). Conclusions: rEsAMA1 and rEsIMP1 could induce cellular and humoral immunity, protecting against E. stiedae infection. Thus, rEsAMA1 and rEsIMP1 are potential vaccine candidates against E. stiedae. [ABSTRACT FROM AUTHOR]

Eimeria magna is a common coccidia in the intestines of rabbits, causing anorexia, weight loss, diarrhea, and bloody stools. This study cloned and determined the expression levels of four Eimeria surface antigens (EmSAGs) at different developmental stages and showed that EmSAG10 and EmSAG11 are highly expressed at the merozoite stage. Rabbits were immunized with rEmSAG10 and rEmSAG11, and then challenged with E. magna after 2 weeks. Serum-specific antibodies and cytokine levels were detected using ELISA. Immune protection was evaluated based on the rate of the oocysts decrease, the output of oocysts (p < 0.05), the average weight gain, and the feed: meat ratio. Our results showed that rabbits immunized with rEmSAG10 and rEmSAG11 had a higher average weight gain (62.7%, 61.1%), feed; meat ratio (3.8:1, 4.5:1), and the oocysts decrease rate (70.8%, 81.2%) than those in the control group, and also significantly reduced intestinal lesions. The specific IgG level increased one week after the first rEmSAG10 and rEmSAG11 immunization and was maintained until two weeks after the challenge (p < 0.05). The TGF-β, IL-4, and IL-10 levels in the serum increased significantly after the secondary immunization with rEmSAG10 and rEmSAG11, while the IL-2 levels increased significantly after the secondary immunization with rEmSAG11 (both p < 0.05), suggesting that rEmSAG10 can induce a humoral and cellular immunity, while rEmSAG11 can only induce a humoral immunity. Therefore, rEmSAG10 is a candidate antigen for E. magna recombinant subunit vaccines. [ABSTRACT FROM AUTHOR]

Background: Psoroptes ovis var. cuniculi is a common ectoparasite of wild and domestic rabbits worldwide that causes economically devastating losses in commercial rabbit husbandry and significantly affects the overall health of rabbits. Serine proteinase inhibitor (serpin) is present in almost all organisms that are involved in host–pathogen interactions, inflammatory responses, and reproductive development, among others. However, very little research has been carried out on P. ovis var. cuniculi serpins. Methods: Two serpin genes of P. ovis var. cuniculi (Pso c 27 and PsoSP2 cDNAs) were cloned and molecularly characterized. The transcriptional profiles and tissue localization of these two serpins in P. ovis var. cuniculi were investigated by quantitative real-time PCR and immunohistochemistry, respectively. The potential function of recombinant Pso c 27 and PsoSP2 (rPso c 27 and rPsoSP2) in the serodiagnosis of P. ovis var. cuniculi infestation in rabbits was evaluated using a newly devleoped indirect enzyme-linked immunosorbent assay. Results: Both the 523-residue Pso c 27 and the 240-residue PsoSP2 proteins contained typical serpin domains and signatures. Both Pso c 27and PsoSP2 cDNAs were expressed throughout the life-cycle; specifically, the cDNAs showed significantly higher expression in female mites than in larva, nymph, and male mites (Pso c 27: F(3, 8) = 1935.953, P < 0.0001; PsoSP2: F(3, 8) = 660.669, P < 0.0001). The native Pso c 27 and PsoSP2 proteins localized in the ovary and mouthparts of adult female mites, respectively. Compared to rPsoSP2, rPso c 27 showed better diagnostic efficiency, with higher values of sensitivity, specificity, and area under the receiver operating characteristic curve (rPso c 27 vs rPsoSP2: 96.0 vs 90.0%; 90.91 vs 78.18%; 0.988 vs 0.964, respectively). Moreover, rPso c 27 showed seropositivity in 80% of the rabbits as early as the 2 weeks post-infestation, prior to visible clinical signs and microscopy-positive of skin scrapings. Conclusions: These results suggest that these two serpins may play essential roles in reproductive development, serum-feeding, and pathogenicity of P. ovis var. cuniculi. Compared to PsoSP2, Pso c 27 appears to be a potential antigen for serodiagnosis of P. ovis var. cuniculi infestation in rabbits, especially at the early stage of infestation. [ABSTRACT FROM AUTHOR]

Background: Scabies, caused by infestation of the mite Sarcoptes scabiei, is one of the most severe ectoparasitic diseases in rabbits. Scabies seriously affects the commercial rabbit breeding, causing severe economic losses. Host resistance to S. scabiei is an important factor in further development of the rabbit industry. In the present study, we compared the host resistance to S. scabiei var. cuniculi of a new breed of domestic rabbit propagated by the Sichuan Animal Sciences Academy (QiXing rabbit, QX) compared with that of a traditional rabbit breed in the domestic rabbit industry (IRA rabbit, IRA). Methods: Both QX and IRA rabbits were experimentally infested with live S. scabiei var. cuniculi mites for 48 h. Then, during the course of four-week experimental infestation period, the body weight of rabbits was recorded every two weeks for calculating body-weight variations in comparison to the non-infested control rabbits. Skin lesions in the foot area were assessed on weekly basis and serum samples were tested weekly for the estimation of changes in the total antibody levels (IgG, IgE and IgM). Moreover, DNA extracted from the blood samples was amplified for analysis of the genetic diversity in the major histocompatibility complex, class II, DQ Alpha (MHC-DQA) gene. Results: Compared to the IRA rabbits, the QX rabbits showed a significantly higher (P < 0.05) relative body weight gain compared to the non-infested control rabbits and significantly lower (P < 0.05) scores for foot skin lesions and higher levels of IgG, IgE and IgM at weeks 1 to 4, week 2 and week 1 post-infestation, respectively. Furthermore, a polymorphism site at position 103 bp of exon two of MHC-DQA gene and a different gene frequency were found between two rabbit breeds, suggesting the genetic basis for the differential host resistance to the S. scabiei var. cuniculi between two rabbit breeds. Conclusions: The QX rabbits showed higher host resistance to S. scabiei var. cuniculi compared to the IRA rabbits at the clinical, immunological and genetic levels. These results provide a reference for the breeding of rabbits with adequately improved and sustained host resistance to scabies in the domestic rabbit industry. [ABSTRACT FROM AUTHOR]

Scabies is a parasitic disease, caused by the mite Sarcoptes scabiei, and is considered one of the top 50 epidemic diseases and one the most common human skin disease, worldwide. Allergic dermatitis, including an intense itch, is a common symptom, however diagnosis is difficult and there is currently no effective vaccine. The goal of this study was to examine the immune interaction mechanism of both S. scabiei and infected hosts. mRNA-seq and microRNA-seq were conducted on the S. scabiei mite and on infected and uninfected hosts. We focused on differential expression of unigenes and microRNAs, as well as the real targets of unigenes in enriched immune signaling pathways. S. scabiei enhanced host immune function and decreased metabolism after infection, while the immune response of the host inhibited S. scabiei proliferation and metabolism signaling pathways. Differentially expressed unigenes of S. scabiei were enriched in the JAK-STAT signaling pathway and the Toll-like receptor signaling pathway. The differential expression analysis indicated that microRNAs of S. scabiei and hosts have major roles in regulating immune interactions between parasites and hosts. [ABSTRACT FROM AUTHOR]

Background: Scabies impairs the health of humans and animals and causes heavy economic losses. Traditional diagnostic methods for scabies are inefficient and ineffective, and so far there is no commercial immunodiagnostic or molecular based test for scabies.Methods: Here, we used recombinant Sarcoptes scabiei cofilin protein as an antigen to establish indirect ELISA. S. scabiei cofilin is highly homologous to Dermatophagoides farinae Der f 31 allergen (90% identity). The S. scabiei cofilin gene was cloned and expressed in Escherichia coli to obtain recombinant protein. Western blotting and fluorescence immunohistochemistry were carried out, and we established an indirect ELISA method and detected 33 serum samples from scabies infected rabbits and 30 serum samples from naïve rabbits.Results: Western blotting demonstrated that S. scabiei cofilin possessed good immunogenicity and fluorescence immunohistochemistry showed the S. scabiei cofilin is widespread in the splanchnic area of mites. In ELISA, a cut-off value of 0.188 was determined to judge experimental positive and negative serum values. Specificity and sensitivity of the ELISA were 87.9 and 83.33%, respectively.Conclusions: Recombinant S. scabiei cofilin showed potential value as a diagnostic antigen. The ELISA method established could be used in clinical diagnosis and provide experimental information in minimal or asymptomatic infection. [ABSTRACT FROM AUTHOR]

Eimeria stiedai is an apicomplexan protozoan parasite that invades the liver and bile duct epithelial cells in rabbits and causes severe hepatic coccidiosis, resulting in significant economic losses in the domestic rabbit industry. Hepatic coccidiosis lacks the typical clinical symptoms and there is a lack of effective premortem tools to timely diagnose this disease. Therefore, in the present study we cloned and expressed the two microneme proteins i.e., microneme protein 1 (EsMIC1) and microneme protein 3 (EsMIC3) from E. stiedai and used them as recombinant antigens to develop a serodiagnostic method for an effective diagnosis of hepatic coccidiosis. The cDNAs encoding EsMIC1 and EsMIC3 were cloned and the mRNA expression levels of these two genes at different developmental stages of E. stiedai were determined by quantitative real-time PCR analysis (qRT-PCR). The immunoreactivity of recombinant EsMIC1 (rEsMIC1) and EsMIC3 (rEsMIC3) proteins were detected by Western blotting, and indirect enzyme-linked immunosorbent assays (ELISAs) based on these two recombinant antigens were established to evaluate their serodiagnostic potential. Our results showed that the proteins encoded by the ORFs of EsMIC1 (711 bp) and EsMIC3 (891 bp) were approximately 25.89 and 32.39 kDa in predicted molecular weight, respectively. Both EsMIC1 and EsMIC3 showed the highest mRNA expression levels in the merozoites stage of E. stiedai. Western blotting analysis revealed that both recombinant proteins were recognized by E. stiedai positive sera, and the indirect ELISAs using rEsMIC1 and rEsMIC3 were developed based on their good immunoreactivity, with 100% (48/48) sensitivity and 97.9% (47/48) specificity for rEsMIC1 with 100% (48/48) sensitivity and 100% (48/48) specificity for rEsMIC3, respectively. Moreover, rEsMIC1- and rEsMIC3-based indirect ELISA were able to detect corresponding antibodies in sera at days 6, 8, and 10 post E. stiedai infection, with the highest positive diagnostic rate (62.5% (30/48) for rEsMIC1 and 66.7% (32/48) for rEsMIC3) observed at day 10 post infection. Therefore, both EsMIC1 and EsMIC3 can be used as potential serodiagnostic candidate antigens for hepatic coccidiosis caused by E. stiedai. [ABSTRACT FROM AUTHOR]

• Metarhizium anisopliae against Psoroptes ovis var. cuniculi in a preliminary stud y. • In vitro , 109 conidia/mL of M. anisopliae evoked 83.33 % mortality at day 9. • In vivo , a single dose of M.anisopliae achieved 100 % efficacy after 3 days. • M. anisopliae was efficient against P. ovis var. cuniculi in a preliminary study. The entomopathogenic fungi Metarhizium anisopliae is highly pathogenic toward arthropods. Here, we evaluated the efficacy of a commercial formulation of M. anisopliae against P. ovis var. cuniculi in vivo and in vitro and explored the acaricidal mechanism of M. anisopliae by determining the antioxidant/detoxification-related enzymes activities including glutathione S-transferase (GST), superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in mites. The results showed that M. anisopliae had high acaricidal activity against P. ovis var. cuniculi in vitro , in a time- and dose-dependent manner, with 83.33 % mortality at day 9 and a median lethal time (LT 50) of 6.10 days after applying 6.14 × 109 conidia/ml of M. anisopliae. In vivo experiments, M. anisopliae achieved 100 % therapeutic effect after 3 days, compared with only 62.21 % for ivermectin. Enzyme assays showed that M. anisopliae significantly upregulated activities of GST, SOD and CAT in Psoroptes mites. The results indicate that M. anisopliae may be an effective biological agent for control of P. ovis var. cuniculi infestations in rabbits and the acaricidal activity may be associated with the changes of enzyme activities of the detoxification and antioxidant system in Psoroptes mites. [ABSTRACT FROM AUTHOR]

Scabies is a highly contagious disease caused by Sarcoptes scabiei which burrows into stratum corneum of host's skin. In this study, after optimizing vaccination schedule, a vaccination trial is comprised of three test groups of rabbits (n = 10/group) by immunization with (1) rSsCLP5; (2) rSsCLP12; or (3) a mixture of rSsCLP5 and rSsCLP12, three biological replicates groups (n = 10/group) and three control groups (n = 10/group). Levels of specific IgG, total IgE and cytokines in sera were detected and histopathologically analyzed as indicators of vaccine effects. The results showed that 85% (17/20) of rabbits exhibited no detectable skin lesions of S. scabiei infestation in mixed protein groups compared to single protein groups with 75% (15/20) and 70% (14/20), respectively. Moreover, the deworming rates of mixed groups are increased by 10%–20% compared with that of single groups. Each of six groups immunized with rSsCLP displayed significant increases of specific IgG, total IgE, IL-10, and TNF-α. The degree of skin damage in test groups also significantly lower than that of control groups. Thus, purified rSsCLP5 and rSsCLP12 subunit cocktail vaccine induced robust immune protection and could significantly decrease mite populations to reduce the direct transmission between rabbits. [ABSTRACT FROM AUTHOR]

Highlights • Beauveria bassiana was clinically tested against P. ovis var. cuniculi in rabbits. • In vitro , 100% of mites died over a 9-day period (LT 50 = 2.50 d) when treated with 4.26 × 109 conidia/ml of B. bassiana. • In vivo , application of 4.26 × 109 conidia/ml resulted in a 100% therapeutic effect in rabbits. • B. bassiana thus offers potential as a biocontrol agent of psoroptic mange disease. Abstract Beauveria bassiana is an entomopathogenic fungus known for its high efficacy against many agricultural insect pests, and is considered to be safe to the environment. Previous studies showed that B. bassiana is also capable of infection and horizontal transmission between Psoroptes ovis mites, but we still lack information on the clinical efficacy of B. bassiana against P. ovis. In this study, we evaluated the acaricidal efficacy of B. bassiana against Psoroptes ovis var. cuniculi , both in vitro and in vivo. Tests consistently showed that B. bassiana caused high mortality against P. ovis var. cuniculi in vitro with dose- and time-dependent susceptibility responses; applying 4.26 × 109 conidia/ml resulted in 100% mortality of P. ovis var. cuniculi within 9 days with an LT 50 of 2.50. In vivo , rabbits infected with P. ovis var. cuniculi that were treated with 4.26 × 109 conidia/ml B. bassiana fungal suspension showed a 100% therapeutic response 3 days later, an efficacy greater than that of the anti-parasitic drug ivermectin. Moreover, no rabbits treated with B. bassiana showed symptoms of disease recurrence by 60 days post-treatment. Taken together, these results show that B. bassiana has high efficacy against P. ovis var. cuniculi ; hence, it may be a potentially effective biological insecticide for use against psoroptic mange. [ABSTRACT FROM AUTHOR]

Sarcoptes scabiei cause scabies in humans or sarcoptic mange in animals. Currently, information regarding vaccines against S. scabiei is limited and no commercial vaccine is available. In present study, we expressed and mixed recombinant S. scabiei serpin (rSs-serpin), recombinant S. scabiei chitinase-like protein-5 [rSs-CLP5] and −12 [rSs-CLP12] as a cocktail vaccine (three proteins mixed), and also a multi-epitope protein derived from these three S. scabiei genes was expressed as a vaccine candidate to evaluate the effects of two vaccine strategies. Four test groups (n = 12 per group) and a control group (n = 12 per group) were involved in this vaccination trial. The results showed that 91.67% (11/12) and 83.33% (10/12) of rabbits exhibited no detectable skin lesions from S. scabiei infestation in cocktail vaccine groups, whereas two multi-epitope groups produced only a few rabbits (5/12, 6/12) having no detectable skin lesions. Four test groups displayed significant increases in specific IgG antibodies (Abs) and total IgE Abs after immunized with recombinant proteins. Taken together, our data demonstrated a mixture of rSs-serpin, rSs-CLP5 and rSs-CLP12 was a promising vaccine candidate that induced robust immune protection and could significantly decrease mite populations to reduce the direct transmission between rabbits. However, vaccination with the multi-epitope protein showed limited protection in rabbits. [Display omitted] • The cocktail vaccine induced robust immune protection. • The cocktail vaccine could significantly decrease mite populations. • The multi-epitope vaccine showed limited protection in rabbits. • The cocktail vaccine is a promising vaccine candidate compared with the multi-epitope vaccine. [ABSTRACT FROM AUTHOR]