A blood digestion scoring method for poultry red mites, Dermanyssus gallinae.

The poultry red mite (PRM), Dermanyssus gallinae, is one of the most detrimental ectoparasite on poultry farms worldwide. The blood fed on birds provides the mites with nutrition and energy for their activities, development and reproduction. In the evaluation of the efficacy of novel drugs or vaccines against PRMs, their effects on blood digestion are generally used as a key parameter. The blood digestion of haematophagous arthropods (including D. gallinae) is usually assessed by weighing; however, this method shows some limitations. The main objective of the present study was to develop a scoring method that can quickly and visually evaluate the blood digestion status of PRMs. A 0­4 point scoring criterion was established to describe the blood digestion status of D. gallinae based on the changes in appearance in the intestinal tract of PRMs during the blood digestion process. There was a good consistency between the results obtained by the blood digestion scoring and the weighing, indicating the reliability of this new method. The results obtained from volunteers were consistent with the results from researchers with low coefficient of variation, indicating that the scoring method has good practicability. The applicability of the scoring method was confirmed in an efficacy study, where it was found that doramectin could significantly inhibit the blood digestion of PRMs, lowering the blood digestion score.

Pharmacokinetics of toltrazuril and its metabolites after oral and parenteral administration of novel oil-based suspension based on micro-environmental pH-modifying solid dispersion in rabbits.

Toltrazuril (TOL) is a broad-spectrum anticoccidial drug which is widely used in poultry and livestock. A novel oral suspension based on soybean oil-based TOL micro-environmental pH-modifying solid dispersion (micro pHm SD) and a novel injectable suspension based on white oil-based TOL micro pHm SD were developed, showing high physicochemical stability and high drug release in vitro with good histocompatibility. The present study is to evaluate the pharmacokinetic profiles of TOL and its major metabolites, e.g. toltrazuril sulfoxide (TOLSO) and toltrazuril sulfone (TOLSO2) in rabbits following oral or subcutaneous administration with these two TOL SD suspensions. The plasma concentrations of TOL, TOLSO and TOLSO2 were determined by high performance liquid chromatography (HPLC). Plasma concentration-time data were analyzed by a non-compartmental model analysis. The soybean oil-based TOL suspension after single oral administration at 20 mg/kg body weight (bw) significantly increased the plasma concentrations of TOL, TOLSO and TOLSO2 compared with Baycox® 5 % suspension. Following subcutaneous administration of the white oil-based TOL suspension (20 mg/kg bw), TOL was well absorbed and metabolized more slowly to TOLSO and TOLSO2, compared with oral administration, resulting in the significantly prolonged residence time in rabbits. The two suspensions significantly improved the relative bioavailability of TOL and its two metabolites, showing their potential usage in the control of coccidian in poultry and livestock.

NMCMDA: neural multicategory MiRNA-disease association prediction.

MOTIVATION: There is growing evidence showing that the dysregulations of miRNAs cause diseases through various kinds of the underlying mechanism. Thus, predicting the multiple-category associations between microRNAs (miRNAs) and diseases plays an important role in investigating the roles of miRNAs in diseases. Moreover, in contrast with traditional biological experiments which are time-consuming and expensive, computational approaches for the prediction of multicategory miRNA-disease associations are time-saving and cost-effective that are highly desired for us. RESULTS: We present a novel data-driven end-to-end learning-based method of neural multiple-category miRNA-disease association prediction (NMCMDA) for predicting multiple-category miRNA-disease associations. The NMCMDA has two main components: (i) encoder operates directly on the miRNA-disease heterogeneous network and leverages Graph Neural Network to learn miRNA and disease latent representations, respectively. (ii) Decoder yields miRNA-disease association scores with the learned latent representations as input. Various kinds of encoders and decoders are proposed for NMCMDA. Finally, the NMCMDA with the encoder of Relational Graph Convolutional Network and the neural multirelational decoder (NMR-RGCN) achieves the best prediction performance. We compared the NMCMDA with other baselines on three experimental datasets. The experimental results show that the NMR-RGCN is significantly superior to the state-of-the-art method TDRC in terms of Top-1 precision, Top-1 Recall, and Top-1 F1. Additionally, case studies are provided for two high-risk human diseases (namely, breast cancer and lung cancer) and we also provide the prediction and validation of top-10 miRNA-disease-category associations based on all known data of HMDD v3.2, which further validate the effectiveness and feasibility of the proposed method.

First record of Aspergillus oryzae as an entomopathogenic fungus against the poultry red mite Dermanyssus gallinae.

The poultry red mite, Dermanyssus gallinae, is a blood-feeding ectoparasite that affects egg-laying hens worldwide. Strategies to control this parasite have focused in the use of entomopathogenic fungi, such as Metarhizium anisopliae. However, only a few studies have evaluated the use of Aspergillus oryzae to control D. gallinae and none of them have employed native strains. In the work presented here, a novel entomopathogenic fungus was isolated from a dead D. gallinae. The results of phylogenetic analysis showed 100% similarity between the isolated strain and those of two species, A. oryzae and Aspergillus flavus, and 99.82% similarity with A. parvisclerotigenus, which were in the same branch of the Flavi section of the genus Aspergillus. This entomopathogenic fungus was a non-aflatoxin B1 producer, as shown by the presence of aflatoxin B1 in the conidial infection suspension. Morphological features of fungus in comparison with A. oryzae and A. flavus indicated that the isolated strain belonged to A. oryzae, and was named Aspergillus sp. Dg-1. The pathogenicity of Aspergillus sp. Dg-1 on D. gallinae at different life stages was then assessed under laboratory conditions. The experiments showed that the isolated strain significantly increased the mortality rate in adult mites, up to 24.83 ± 2.25, compared to the mortality rates in the control group, which were 15.17 ± 2.75 (P ＜ 0.05). However, Aspergillus sp. Dg-1 did not have pathogenic effects on the second nymph stage of D. gallinae. Our findings demonstrate that Aspergillus sp. Dg-1 has pathogenic effects on D. gallinae in their adult stage, presenting biocontrol potential against D. gallinae.

Darkness increases the population growth rate of the poultry red mite Dermanyssus gallinae.

BACKGROUND: The poultry red mite (PRM), Dermanyssus gallinae, is one of the most economically deleterious ectoparasites affecting egg-laying hens worldwide. It may be possible to control D. gallinae populations by manipulating lighting regimes within poultry units. However, no studies have clearly shown the effects of darkness on the population growth rate of D. gallinae. METHODS: The effect of darkness on the population growth rate of D. gallinae was investigated, together with the first description of the molecular identity of the mite from China. Mite variables under two lighting regimens (1:23 h L:D and 12:12 h L:D) were compared, including number of mites and eggs, survival and feeding rates, engorgement, oviposition, hatchability and the life-cycle of D. gallinae. RESULTS: The results showed that the number of mites (13,763 ± 956) and eggs (5424 ± 317) in the rearing system with prolonged darkness of 1:23 h L:D at 4th week were 2.4- and 3.6-fold higher than those under a conventional lighting regimen of 12:12 h L:D, respectively. The feeding rates of mites under prolonged darkness ranged from 36.7 ± 1.1% to 52.0 ± 7.0%, which were significantly higher than those under conventional lighting regimen (ranging from 22.6 ± 1.9% to 37.3 ± 1.6%). The mean weight of engorged females (0.26 ± 0.01 mg) and the mean number of eggs per female (on average 5.87 ± 0.36) under prolonged darkness were significantly higher than those under conventional lighting regimen (0.22 ± 0.01 mg and 3.62 ± 0.31, respectively). However, the survival rate ranging from 98.07 ± 0.10% to 98.93 ± 0.19%, hatchability of 97.93 ± 0.01% and the life-cycle of D. gallinae (9 days) was not affected by the lighting period. CONCLUSIONS: Our findings demonstrated that prolonged darkness significantly promoted the proliferation levels of D. gallinae, resulting in increased number of mites and eggs in the rearing system. The promoted population growth of D. gallinae was found to be related to the increased feeding rate, engorgement level and oviposition level of mites under prolonged darkness. The egg hatchability, the survival rates and the duration of life-cycle of D. gallinae were not affected by the light regimes.

An efficient rearing system rapidly producing large quantities of poultry red mites, Dermanyssus gallinae (Acari: Dermanyssidae), under laboratory conditions.

The poultry red mite, Dermanyssus gallinae, is one of the most economically deleterious ectoparasites affecting egg-laying hens in many parts of the world. New approaches to control D. gallinae often require the maintenance of colonies of D. gallinae under laboratory conditions. In the present study, we present an efficient rearing system for D. gallinae, consisting of a metal cage, a plastic storage box and a tray filled with water. Chicks were raised in the cage as host animals. A novel trap was developed to monitor the dynamic changes of mite populations, made with a plastic centrifuge tube and a disposable breathing mask with folds. Mite parameters were analyzed, including number of mites and eggs, survival and feeding rates, oviposition, hatchability and the proportion of D. gallinae at different life stages. The results show that the rearing system had a 53.5-fold increase in the number of mites over a period of six weeks after the introduction of mites. The survival rates of mites were above 94%, and the mean feeding rates ranged from 22.57% to 37.30%. The mean number of eggs per female ranged from 3.42 to 3.50, with the hatchability of eggs above 97%. Nymphs made up most of the population, ranging from 71.46% to 81.37%, while the population of larvae was minor and ranging from 7.54% to 13.04%. The mask trap used in this study was an effective and convenient device to shelter D. gallinae and monitor the dynamic changes of the mite population. The rearing system proved very effective in maintaining and reproducing colonies of D. gallinae, with great potential for the evaluation of the efficacy of vaccines or compounds against D. gallinae under laboratory conditions. It would be a useful tool for close observations in studies on the biology, acology and physiology of poultry red mites.

[CCN3 regulates the proliferation and apoptosis in periodontal ligament fibroblasts].

PURPOSE: To investigate the effect of CCN3 on proliferation and apoptosis in periodontal ligament fibroblasts (PDLFs) and related mechanism. METHODS: Recombinant vector pcDNA.3.1-CCN3 was constructed and transfected into human PDLFs to overexpress CCN3. CCN3 siRNA was transfected to inhibit CCN3. Fra-1 siRNA was transfected into the PDLFs with CCN3 inhibition to realize the inhibition of CCN3 and Fra-1 in the meantime. mRNA expressions of CCN3 and Fra-1 were measured by quantitative real-time PCR (qRT-PCR). The protein expressions of CCN3, Fra-1and Bcl-2 were detected by Western blot. Cell growth and viability and proliferation of PDLFs were measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and bromodeoxyuridine (BrdU) assays; Caspase-3 activity was tested by using the available kit. The data were analyzed with SPSS20.0 software package. RESULTS: The results showed that the mRNA (P<0.05) and protein (P<0.05) expressions of CCN3 were significantly up-regulated in the experimental group of pcDNA.3.1-CCN3 transfection. In addition, the mRNA (P<0.05) and protein (P<0.05) expressions of CCN3 were significantly decreased in the experimental group of CCN3 siRNA transfection. Cell growth (P<0.05) and viability, proliferation (P<0.05) and Bcl-2 (P<0.05) protein expression were increased, while caspase-3 activity (P<0.05) decreased in the PDLFs with CCN3 inhibition. However, CCN3 overexpression exhibited reversed effect. CCN3 overexpression or inhibition could remarkably constrain (P<0.05) or promote (P<0.01) the expression of Fra-1, respectively. Moreover, co-inhibition of CCN3 and Fra-1 could promote apoptosis (P<0.01) and inhibit proliferation (P<0.05) in PDLFs. CONCLUSIONS: The results suggest that inhibition of CCN3 could accelerate proliferation and constrain apoptosis via up-regulating expression of Fra-1 in PDLFs.