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1.
Behav Processes ; 192: 104500, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34509563

RESUMO

Ladybird beetles present as key predator of many agricultural pests. Among them, Eriopis connexa stands out due some important traits for pest management programs such as common occurrence, population selected for resistance to pyrethroid insecticides, and possibility to be commercially available by rearing using alternative prey. Despite that, little is known about the role of polyandry and its effect on paternity in this species. Ladybird beetles engage in multiple matings, raising questions about the benefits of polyandry and paternity. We studied the selection of mating pair, sperm precedence, and offspring paternity by performing experiments on (1) the age of sexual maturity, (2) the frequency and refractory mating behavior within a photophase period, (3) the preference of insecticide-susceptible females to mate with either susceptible or resistant male phenotypes; and (4) the effect of multiple matings, on progeny paternity. Sexual maturity in E. connexa was found to begin within 3 days of adult emergence for both sexes, but fully developed after 5 days. The highest frequency of mating exhibited by sexual mature pairs occurred within first hour of pairing and the phenotype for insecticide resistance did not affect the choice of a mating partner. The resistance trait marker in the resistant beetle phenotype indicates that progeny paternity results from a mixture of available sperm and do not depend on mating order. These data suggest that released beetles would have a simple prospect for progeny production for both insecticide resistant and susceptible beetles.


Assuntos
Besouros , Piretrinas , Animais , Pai , Feminino , Humanos , Resistência a Inseticidas , Masculino , Reprodução , Comportamento Sexual Animal , Espermatozoides
2.
Zootaxa ; 4568(3): zootaxa.4568.3.5, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-31715846

RESUMO

The immature stages of Casignetus MacLeay, 1819 (Coleoptera: Lucanidae: Lucaninae: Casignetini) are revised with the description of third instars of males and female of C. humboldti (Gyllenhal, 1817), and C. spixi (Perty, 1830), and female of C. lindei (Boileau, 1899). Pupae of both sexes of C. humboldti, and female of C. lindei are also described for the first time. Casignetus larvae can be recognized by the form of the pars stridens, formed by a slightly arched, longitudinal row of robust, and sclerotized teeth, and by the fusion of the femur and trochanter in prothoracic and mesothoracic legs. Additionally, new characters are proposed for Casignetus species: frontal sutures curvature; epicranial setae; epipharynx and hypopharynx setae; and number and shape of stridulatory teeth.


Assuntos
Besouros , Animais , Feminino , Cabeça , Larva , Masculino , Pupa
3.
Cryobiology ; 87: 74-77, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30731072

RESUMO

The current study assessed a semen cryopreservation protocol in the Amazonian catfish Leiarius marmoratus, a freshwater fish, of rheophilic behavior, and of great importance for Brazilian fish farming. Eight males (n = 8) were stripped and the semen was cryopreserved if total motility in fresh semen was higher than 80%. The external cryoprotectant Trehalose was then diluted in Beltsvile Thawing Solution (BTS) extender in the following concentrations: 50, 100, 150, and 200 mM. Semen samples were diluted in the media (1:9 v/v) being tested, then frozen in a container with nitrogen vapor (dryshipper), and stored in liquid nitrogen at -196 °C. Motility parameters assessed post-thawing were performed by CASA-system and sperm cell integrity analyses (membrane integrity, DNA integrity, and mitochondrial function) were performed through fluorescence microscopy. As a result, no significant statistical difference was observed between treatments, independently of Trehalose concentrations tested in the following post-thawing analysis: membrane integrity, DNA integrity, mitochondrial functionality, and sperm motility duration. As of total and progressive motilities, the treatment containing 50 mM trehalose (15.6 and 9.5%, respectively), exhibited inferior results when compared to treatments with 150 mM (22.9 and 17.7%, respectively) and 200 mM (31.4 and 26.3%, respectively) trehalose concentrations (P < 0.05); however, it did not differ from the treatment with 100 mM trehalose (18.6 and 15.3%, respectively). Therefore, treatments with trehalose at higher concentrations exhibited superior results when compared to other treatments in in vitro motility parameters for L. marmoratus.


Assuntos
Criopreservação/métodos , Crioprotetores/farmacologia , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/efeitos dos fármacos , Trealose/farmacologia , Animais , Peixes-Gato , Membrana Celular/fisiologia , Congelamento , Masculino , Mitocôndrias/fisiologia , Sêmen/fisiologia , Análise do Sêmen , Espermatozoides/fisiologia
4.
Pesqui. vet. bras ; 36(11): 1116-1120, Nov. 2016. tab, graf, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-842015

RESUMO

O estudo do desenvolvimento embriológico de órgãos reprodutivos representa uma ferramenta importante para a compreensão das particularidades da espécie equina, assim como ampliar os conhecimentos sobre o desenvolvimento de folículos antrais que podem ser utilizados para produção in vitro de embriões. O presente trabalho teve como objetivo descrever as alterações morfológicas de ovários fetais equinos ocorrentes durante o desenvolvimento gestacional. Foram utilizados fetos equinos provenientes de abatedouro. Imediatamente após o abate foi realizada medição da distância cefalococcígea para o cálculo da idade gestacional em dias (dias de gestação - DG) e dissecação dos fetos para a retirada e fixação dos ovários. Foram realizadas avaliações macroscópicas e histológicas pelas técnicas de Hematoxilina-eosina e PAS. Foram utilizados 19 fetos com idade de 50-269 dias de gestação, distribuídos em 9 grupos de DG. Na avaliação macroscópica foi observada diferença entre o volume dos ovários de acordo com a idade gestacional, sendo observado maior volume ovariano entre os dias 210 a 269 de desenvolvimento gestacional. Na avaliação histológica foi observado epitélio de revestimento cúbico e distinção entre as camadas cortical e medular nos ovários fetais a partir de 50-89 DG. As principais características identificadas foram à distinção morfológica entre as camadas cortical e medular nos ovários fetais equinos: os cordões ovígeros surgiram no intervalo de 150-179 DG; o córtex iniciada como uma camada delgada e por volta do 210º dia de gestação apresentou espessamento pelo aumento da quantidade de tecido conjuntivo rico em vasos sanguíneos, o qual se manteve até os estágios finais da gestação; a região medular adquiriu uniformidade estrutural por volta do 150º dia, mostrando células similares em tamanho e vasos sanguíneos de calibre maior. A partir desta etapa, as células medulares diminuíram em tamanho e feixes de tecido conjuntivo denso tornaram esta zona parcialmente dividida.(AU)


The study of embryological development of reproductive organs is an important tool for understanding the particularities of the equine species. Also it is important for increasing knowledge about the development of antral follicles that can be used for in vitro production of embryos. This study aimed to describe the morphological changes of fetal equine ovaries occurring during gestational development. It was used equine fetuses from a slaughterhouse. After slaughter, it was performed the measurement of cefalococcígea distance to calculate the gestational age (days of pregnancy - DP). Afterwards, the ovaries were grossly evaluated, removed and fixed. Then, they were histologically assessed by hematoxylin-eosin and PAS techniques. It was used 19 fetuses aged 50 to 269 days of gestation, distributed in 9 groups divided according to DP. In the grossly evaluation, it was observed differences between the volume of the ovaries according to gestational age, being observed bigger/larger ovarian volume between 210 days to 269 DP. During the histological evaluation, it was observed a simple cuboidal epithelium and a distinction between the cortical and medullary layers in fetal ovaries from 50-89 DP. The main characteristics identified were: the morphological distinction between the cortical and medullary layers in equine fetal ovaries; the ovigerous cords emerged in the interval between 150 and 179 DP; the cortex initiated as a thin layer with an increased amount of connective tissue rich in blood vessels by the 210 DP, structural uniformity acquired in the medular region by the 150 DP, showing similar cells in size and blood vessels of larger caliber. From this stage, the cells in this region had decreased in size and dense connective tissue bundles, which made this zone partially divided.(AU)


Assuntos
Animais , Feminino , Desenvolvimento Fetal/fisiologia , Cavalos/anatomia & histologia , Cavalos/crescimento & desenvolvimento , Cavalos/fisiologia , Ovário/crescimento & desenvolvimento , Técnicas Histológicas/veterinária
5.
J Hazard Mater ; 169(1-3): 965-71, 2009 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-19443113

RESUMO

Ozonation of two azo dyes was investigated in a monitored bench scale bubble column reactor (8.5-L), varying liquid media salt content (0, 1, 40 and 100 g L(-1), NaCl). In experiments with Orange II pH was varied (5, 7.5 and 9) but ozonation of Acid Red 27 was performed at pH 7.5. Ozone self-decomposition rate-constant increased with salt concentration. Color removal was very effective and fast achieved under all experimental conditions. For the two azo dyes tested, more than 98% of color intensity was removed in 30-min ozonation assays. However, only partial mineralization of azo dyes (45%-Orange II; 20%-Acid Red 27) was attained in such experiments. The degree of mineralization (TOC removal) was negatively affected by salt concentration. Biodegradation assays conducted by respirometry revealed the inhibitory effect of dye degradation products formed during ozonation.


Assuntos
Compostos Azo/química , Corantes/química , Resíduos Industriais/prevenção & controle , Ozônio/química , Corante Amaranto , Benzenossulfonatos/química , Carbono , Projetos Piloto , Cloreto de Sódio , Esterilização , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/química , Purificação da Água/métodos
6.
J Hazard Mater ; 117(2-3): 235-42, 2005 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-15629582

RESUMO

This work shows an evaluation of treatments for the leachate produced at the Gramacho Municipal Landfill in Rio de Janeiro state, Brazil. This leachate has very peculiar characteristics, with a high salinity level and very low biodegradability (BOD(5)/COD of 0.05). A sequence of processes was employed in the treatment of this leachate. Initially, a physicochemical treatment was used, while the second stage consisted of application of ozone to improve the biodegradability of the leachate. The final stage comprised a biological treatment. The physical-chemical treatment led to COD and DOC removal levels of 40 and 25%, respectively, with the use of Al(2)(SO(4))(3). The sequence of treatments proposed brought good results, with an increase in the BOD(5)/COD ratio from 0.05 to 0.3 after ozonation. The toxicity tests performed using Brachydanio rerio and Poecilia vivipara showed that the toxicity of the leachate had hardly been reduced by ozonation. These results are in agreement with the fact that, despite the higher BOD(5)/COD ratio, the biological process did not present a good performance. The total average removal levels of COD and DOC achieved using the combined treatment were 73 and 63%, respectively, for an ozone dose of 3.0 gL(-1) by the leachate.


Assuntos
Ozônio/química , Eliminação de Resíduos/métodos , Esgotos/química , Poluição da Água/prevenção & controle , Animais , Biodegradação Ambiental , Floculação , Poecilia , Testes de Toxicidade/métodos , Peixe-Zebra
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