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For ensuring the effectiveness of sterile insect technique ( SIT) programmes, maintaining the reproductive competitiveness and dispersal ability of mass-reared sterile males is essential. Inadvertent selection is an important genetic process that frequently occurs during mass rearing to produce sterile males. We investigated the effect of mass-rearing conditions on the responsiveness to sex pheromones and spontaneous flight activity of males of the sweetpotato weevil Cylas formicarius ( Coleoptera: Brentidae). There were no significant differences in the responsiveness to sex pheromones and spontaneous flight activity between wild and mass-reared strains. These results indicate that mass-reared strains of C. formicarius might not cause serious problems for implementing SIT programmes. [ABSTRACT FROM AUTHOR]

The sweetpotato weevil Cylas formicarius ( Fabricius) ( Coleoptera: Brentidae) and West Indian sweetpotato weevil Euscepes postfasciatus ( Fairmaire) ( Coleoptera: Curculionidae) are major pests of sweet potato Ipomoea batatas ( L.) Lam., in tropical and subtropical regions. Effects of intra- and inter-specific competition on the number of progeny (fecundity), body weight and developmental time of C. formicarius and E. postfasciatus were examined in single- and mixed-species treatments under laboratory conditions. Cylas formicarius tended to outcompete E. postfasciatus, whereas E. postfasciatus rather than C. formicarius tolerated higher conspecific densities. We discuss the implications of the results for pest management and resource partitioning of pestiferous weevils. [ABSTRACT FROM AUTHOR]

Purpose: It is necessary to correlate cancellous bone patterns with cone beam computed tomography (CBCT) images, but this has not been done to date. The goal of this study was to establish how the superior wall of the mandibular canal (MC) on CBCT images correlates with the cancellous bone around the MC on gross anatomical findings., Methods: Twenty sides from 10 dry mandibles derived from six females and four males were used for this study. In order to observe the MC distally, the specimen was prepared by the method used in our previous study. The cancellous bone around the MC was observed and classified into three types: type I (trabecular pattern), type II (osteoporotic pattern), and type III (dense/irregular pattern). The mandibles were examined with CBCT and the superior wall of the MC on CBCT was scored as visible or non-visible. Finally, the scores (visible or non-visible) were compared to the type by gross observation., Results: For gross observation, a total of 80 areas were available for this study. The data were added to those from our previous study. As a result, 155 areas on 40 sides were analyzed. In dentulous sections, types I, II, and III were found in 55.8%, 20.9%, and 23.3%, respectively. In edentulous sections, the corresponding percentages were 25.0%, 41.1%, and 33.9%, respectively. The dentulous sections was more likely than edentulous to have a type I mandible in both sexes. More females than males had type II (osteoporotic) mandibles. When the superior wall of the MC was non-visible on CBCT, the cancellous bone was type II in 80%., Conclusions: We believe the results can easily be applied to preoperative diagnosis with not only radiological but also anatomical evidence. This classification now necessitates clinical trials for further evidence., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

Purpose: Periosteal releasing incision (PRI) techniques are often used with guided bone regeneration procedures. As complications such as intra- and postoperative bleeding have been noticed, we aimed to study and clarify these as related to the PRI, especially on the mandibular buccal periosteum., Methods: Fourteen sides from seven fresh-frozen Caucasian cadaveric heads were used in this study. The seven cadavers were derived from two females and five males. The mean age at the time of death was 75.9 ± 10.8 years. The PRI was made using a no. 15c blade using a surgical microscope. Subsequently, the fat tissue lateral to the periosteum was slightly dissected. The diameter of the facial artery (or its branch) and closest relationship between the tooth and position of the artery was recorded. Finally, the artery was traced back proximally to clarify its origin., Results: On all sides, the inferior labial artery (ILA) was identified in the fat tissue lateral to and close to the periosteum. The ILA was closest to the periosteum at the midpoint of the PRI (approximately between the first and second molar teeth area or 10 mm mesial to the apex of the retromolar pad). The mean diameter of the ILA was 2.72 ± 0.26 mm., Conclusion: This anatomical finding should encourage dentists to make the PRI incision without invading the tissue underneath the periosteum.

Cattle exhibit a range of carcass defects, including blood splash (BLS), intramuscular edema (INE), muscle steatosis (MUS), bruising (BR), trim loss (TRL) and others (OTH). These defects lower the carcass value and can result in significant economic loss to producers. We estimated the incidence, relationship with inbreeding coefficients and genetic parameters of carcass defects in Japanese Black cattle using 561 619 carcass records from Kagoshima, Japan during April 1988 through March 2011. The defect incidence ranged from 0.22% for TRL to 5.73% for BR. The incidence of MUS and BR increased from 1.21% to 6.57% and from 1.06% to 9.31%, respectively. The incidence of INE peaked at 7.44% in 1999 and decreased thereafter. We observed a positive linear relationship between the defect incidence and the inbreeding coefficients in MUS, BR and TRL (P < 0.01). The heritabilities estimated by univariate animal model with Gibbs sampling for BLS, INE, MUS, BR and TRL were 0.24, 0.06, 0.18, 0.05 and 0.02, respectively. The contribution of farm variance to phenotypic variance was negligible (0.01 to 0.04). Significant genetic correlations of TRL were estimated with MUS (0.63) and BR (0.63). Our results suggest that genetic factors contribute to the incidence of BLS and MUS., (© 2015 Japanese Society of Animal Science.)

The sterile insect technique (SIT) is widely used for suppressing or eradicating target pest insect populations. In the eradication programs using the SIT, a large number of sterile insects are marked and released in the field. In Japan, Cylas fonnrmicarius (F.) group (Coleoptera: Brentidae) weevils are marked with a fluorescent powder dye to monitor the progress of such programs. However, this monitoring technique is not fully effective because of the disappearance or contamination of the dye. Therefore, an alternative marking method is required. Currently, a rare color morph such as piceous elytra (PE) is used for visible marking of C. formicarius group weevils. A PE-monomorphic strain has previously been established by artificial selection from a small locally distributed population; this can lead to reduced survival and genetic changes in behavioral traits due to inbreeding depression. In this study, we evaluated the survival rate and mating behavior of PE males of C. formicarius group. The characteristics of the PE males were similar to those of the wild strain (WS) males. Thus, we considered that PE males were suitable for visible marking in the eradication programs using the SIT.

The number of West Indian sweet potato weevils, Euscepes postfasciatus, being mass-reared in a facility for use in sterile insect technique (SIT) eradication programs has undergone a drastic reduction. A neogregarine protozoan pathogen Farinocystis sp. (an undescribed species) was detected in vivo in the mass-reared E. postfasciatus. We investigated the effects of this disease on the longevity and fecundity of host weevils and the incubation time of the disease in the host body under mass-rearing conditions. Our results demonstrated that infection by this Farinocystis sp. decreased both longevity and fecundity in E. postfasciatus. In particular, the pathogen severely limited the production of progeny by infected females compared to healthy females. Therefore, we consider this protozoan infection to be the major cause of the decreased E. postfasciatus production in the mass-rearing facility., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Weevils constitute the most species-rich animal group with over 60,000 described species, many of which possess specialized symbiotic organs and harbor bacterial endosymbionts. Among the diverse microbial associates of weevils, Nardonella spp. represent the most ancient and widespread endosymbiont lineage, having co-speciated with the host weevils for over 125 million years. Thus far, however, no empirical work on the role of Nardonella for weevil biology has been reported. Here we investigated the biological role of the Nardonella endosymbiont for the West Indian sweet potato weevil, Euscepes postfasciatus. This insect is an experimentally tractable pest insect that can easily be reared on a natural diet of sweet potato root as well as on an agar-based artificial diet. By larval feeding on an antibiotic-containing artificial diet, Nardonella infection was effectively eliminated from the treated insects. The antibiotic-treated insects exhibited significantly lighter body weight and lower growth rate than the control insects. Then, the antibiotic-treated insects and the control insects were respectively allowed to mate and oviposit on fresh sweet potatoes without the antibiotic. The offspring of the antibiotic-treated insects, which were all Nardonella-negative, exhibited significantly lighter body weight, smaller body size, lower growth rate and paler body color in comparison with the offspring of the control insects, which were all Nardonella-positive. In conclusion, the Nardonella endosymbiont is involved in normal growth and development of the host weevil. The biological role of the endosymbiont probably underlies the long-lasting host-symbiont co-speciation in the evolutionary course of weevils.