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101.
102.
Lateralization (i.e. left–right asymmetries in the brain and behaviour) has been documented in all vertebrate classes, while evidences for invertebrates are limited. To the best of our knowledge, there is no information about behavioural asymmetries in the order Coleoptera. In this research, we investigated the lateralization of mating traits in two major pests of stored products: the rice weevil, Sitophilus oryzae (Coleoptera: Curculionidae), and the confused flour beetle, Tribolium confusum (Coleoptera: Tenebrionidae). Both T. confusum and S. oryzae males showed population-level left-biased copulation approaches of potential mates. Interestingly, T. confusum and S. oryzae males performing left-biased copulation attempts achieved higher mating success over right-biased males. Furthermore, S. oryzae males periodically exhibited a typical head wagging behaviour, which consists of waving the rostrum laterally across the female thorax and then resting the rostrum on the mid thorax. This behaviour was right-biased, even in the majority of males that previously showed left-biased copulation attempts. The quantification of mating displays could allow comparisons with other strains, in order to evaluate the impact of a given host or of the rearing methods on the mating traits of S. oryzae and T. confusum. Overall, this is the first report of lateralization of mating traits in Coleoptera. Furthermore, this research adds basic knowledge to the reproductive behaviour of S. oryzae and T. confusum.  相似文献   
103.
Jatropha seed cake (JSC) is an excellent source of protein but does contain some antinutritional factors (ANF) that can act as toxins and thus negatively affect the growth and health status of fish. While this can limit the use of JSC, detoxified Jatropha protein isolate (DJPI) may be a better option. An 8-week study was performed to evaluate dietary DJPI to common carp Cyprinus carpio. Five iso-nitrogenous diets (crude protein of 38%) were formulated that consisted of a C ontrol (fish meal (FM) based protein), J 50 or J 75 (50 and 75% of FM protein replaced by DJPI), and S 50 or S 75 (50 and 75% of FM protein replaced by soy protein isolate, SPI) and fed to triplicate groups of 75 carp fingerlings (75; av. wt. ± SD; 11.4 ± 0.25 g). The growth, feeding efficiencies, digestibility, plasma biochemistry, and intestinal enzymes were measured. Results showed that growth performance of fish fed the S 75- or DJPI-based diets were not significantly different from those fed the C ontrol diet, while carp fed the S 50 had significantly better growth than the J 75 diet. Fish fed the J 75 diet had significantly lower protein and lipid digestibility as well as significantly lower intestinal amylase and protease activities than all other groups. However, all plant protein-based diets led to significantly higher crude protein, crude lipid, and gross energy in the body of common carp compared to the control treatment. Plasma cholesterol and creatinine significantly decreased in the plant protein fed groups, although plasma triglyceride as well as the red blood cells count, hematocrit, albumin, globulin, total plasma protein, and lysozyme activity were higher in plant protein fed groups compared to FM fed group. White blood cells, hemoglobulin concentration, alkaline phosphatase and alanine transaminase activities, and glucose level in blood did not differ significantly among treatments. The results suggest that the DJPI is non-toxic to carp and can be used to replace FM in the diets of common carp up to 75%, but further research to potentially reduce some inherent ANF within this protein source, such as non-starch polysaccharides, may improve nutrient utilization.  相似文献   
104.
Mating trophallaxis represents a fascinating strategy adopted by males of several animal species to affect the decision-making of females during mating. Among tephritids, few species perform mating trophallaxis. However, this phenomenon has been little studied in major tephritid pests. We reported the presence of indirect mating trophallaxis in Mediterranean fruit flies, Ceratitis capitata, showing its influence on the main mating traits, male mating success and female egg load. Of 219 mating pairs, only 27 of them showed mating trophallaxis, indicating that mating trophallaxis may represent a significant male energy investment. The duration of male wing vibration and the whole precopula phase was longer in pairs that mated without trophallaxis compared to the pairs displaying mating trophallaxis. Males that displayed trophallaxis performed a longer whole duration of the courtship and mating sequence, with no differences in copula duration. Male mating success was slightly increased by trophallaxis. The majority of males performing trophallaxis skipped wing vibration during courtship, while all males courting females without trophallaxis relied on wing vibration to attract females within short distances. No egg load differences were reported for females that consumed nuptial gifts over control females. Overall, our research sheds light on the relation between indirect mating trophallaxis and egg load production in medflies, providing a better understanding of sexual selective mechanisms as the basis of courtship and mating behaviour in tephritid flies. Furthermore, this behaviour could be used as a quality control parameter to assess medfly mass-reared strains, in order to improve sterile insect technique programmes.  相似文献   
105.
Sponges are known to produce a series of compounds with bioactivities useful for human health. This study was conducted on four sponges collected in the framework of the XXXIV Italian National Antarctic Research Program (PNRA) in November-December 2018, i.e., Mycale (Oxymycale) acerata, Haliclona (Rhizoniera) dancoi, Hemimycale topsenti, and Hemigellius pilosus. Sponge extracts were fractioned and tested against hepatocellular carcinoma (HepG2), lung carcinoma (A549), and melanoma cells (A2058), in order to screen for antiproliferative or cytotoxic activity. Two different chemical classes of compounds, belonging to mycalols and suberitenones, were identified in the active fractions. Mycalols were the most active compounds, and their mechanism of action was also investigated at the gene and protein levels in HepG2 cells. Of the differentially expressed genes, ULK1 and GALNT5 were the most down-regulated genes, while MAPK8 was one of the most up-regulated genes. These genes were previously associated with ferroptosis, a programmed cell death triggered by iron-dependent lipid peroxidation, confirmed at the protein level by the down-regulation of GPX4, a key regulator of ferroptosis, and the up-regulation of NCOA4, involved in iron homeostasis. These data suggest, for the first time, that mycalols act by triggering ferroptosis in HepG2 cells.  相似文献   
106.
The first report of a case of feline phaeohyphomycosis due to Fonsecaea pedrosoi is presented. Fonsecaea pedrosoi is an aetiologic agent of both human phaeohyphomycosis and chromoblastomycosis. In our cat, the lesion was confined to the skin and appeared as a firm swelling on the bridge of the nose. Diagnosis was based on histological examination of a cutaneous biopsy and fungal culture of a tissue sample on Sabouraud's dextrose agar. Further diagnostic tests failed to reveal an underlying immunosuppression. Two treatment cycles with itraconazole, at the oral dose of 5 mg kg-1 given twice daily, induced complete clinical remission, but relapses occurred.  相似文献   
107.
108.
The reproductive tract of the female is a part of the mucosal system which protects from pathogens invasion. We have analysed the presence and distribution of total lymphocytes, plasma cells (antibody secreting B cells) and T lymphocytes subsets in the reproductive tract of the female goat. The influence of the oestrous cycle on the densities of lymphocytes and plasma cells of the cervix and uterus horn was evaluated in sections prepared for conventional histology. Immunocytochemistry was used for the study of lymphocyte subsets by confocal microscopy and immunoperoxidase techniques. Present results show that the reproductive tract of the goat is a site rich in lymphocytes. These cells were found mingled with the epithelial cells of the endometrium and distributed throughout the stroma. Lymphocyte aggregates were observed in the stroma. Lymphocyte but not plasma cell number changed depending on the reproductive stage of the goats. The impact of the hormonal environment was different for the cervix and uterine horn. Immunocytochemistry studies evidenced the presence of cells displaying immunoreactivity for both CD 4+ and CD 8+ antibodies in the epithelial layer and stroma of the cervix and uterine horn. These cells were more numerous in the cervix and were also found infiltrating the luminal epithelia of endometrial glands. Overall, our results indicate that lymphocyte distribution is different in the cervix and the horn, and is influenced by the stage of the reproductive cycle. In summary, CD 4+ and CD 8+ T lymphocytes subsets could be found in the endometrium of both the cervix and uterine horn of the goat reproductive tract.  相似文献   
109.
A total of 894 calves at high risk for bovine respiratory disease were processed at two sites and randomly assigned to receive one of three antimicrobial metaphylactic regimens to determine if a two-drug regimen offered any advantage over the more conventional one-course regimens. On arrival, calves received either a two-course regimen of ceftiofur crystalline free acid (CCFA) followed by tulathromycin 8 days later (Group 1) or a one-course regiment of CCFA (Group 2) or tilmicosin (Group 3). At Site A, morbidity was significantly lower (52%) in Group 1 than in Group 2 (76.3%) and Group 3 (78.4%). At Site B, morbidity was significantly lower in Group 1 (2.6%) than in Group 2 (9.4%) and Group 3 (7.2%).  相似文献   
110.
Lactobacillus rhamnosus as additive for maize and sorghum ensiling   总被引:2,自引:0,他引:2  
The effects of Lactobacillus rhamnosus AT195, a potential probiotic microorganism cultured in buffalo "scotta" whey, on chemical and microbiological composition in maize and sorghum ensiling were evaluated. Both crops were harvested, chopped, and treated or not with the selected strain prior to ensiling in fiberglass vertical silos; 90 days after ensiling, silages were sensorially evaluated and sampled. Different chemical components were evaluated both on fresh crops and silages: in particular, the water-soluble carbohydrates content was investigated by high-field NMR spectroscopy and the carbohydrate fermentation profile was performed by GC. Besides phenotypic identification and typing, microbiological studies included Lb. rhamnosus genotype typing by RAPD-PCR. All silages, inoculated or not, were well preserved, as their chemical and microbiological data along with the fermentation profiles showed. The selected strain used as inoculum influenced the lactic acid population of silages and evidenced a good survival performance during the ensiling process of both maize and sorghum. Moreover, the use of Lb. rhamnosus strain efficiently improved the quality of the multifactorial ensiling process by significantly reducing the ammonia nitrogen content of both maize and sorghum silages.  相似文献   
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