Influence of the residue from an iron mining dam in the growth of two macrophyte species.

On November 5th, 2015 the worst environmental disaster in Brazil spilled 60 million m3 of iron mining residue into Gualaxo do Norte River (Minas Gerais State), an affluent of the highest River Basin of the Brazilian Southeast (Doce River Basin), reaching the Atlantic Ocean. To assess the impact of the iron residue on the aquatic plant metabolism, we performed macrophyte growth experiments under controlled light and temperature conditions using two species (Egeria densa and Chara sp.). The plants' growth data were fitted in a kinetic model to obtain the biomass yields (K) and growth rates (µ). Turbidity and electrical conductivity of the water were measured over time. Both plants showed the highest growth rates in the contaminated condition (0.056 d-1 for E. densa and 0.45 d-1 for Chara sp.) and the biomass increased in the short-term (≈20 days). The control condition (i.e. no impacted water) supported the biomass increasing over time and the development of vegetative buddings with high daily rates (1.75 cm d-1 for E. densa and 0.13 cm d-1 for Chara sp). Turbidity showed a sharp decrease in 48 h and had no effects in the plants growth in the contaminated condition. The contamination affected the plants' yields in the long-term affecting the biomass development. This study provides preliminary information about the ecological consequences of a mining dam rupture aiming to collaborate with monitoring and risk assessments.

Dimorfismo sexual da traquéia e siringe de periquito (Touist sp. ) / Sexual dimorphism of the parakeet (Touist sp. ) trachea and syrinx

Investigaram-se as diferenças morfológicas da siringe do periquito Touist sp, cinco machos e cinco fêmeas. A traquéia e a siringe foram dissecadas com o auxílio de uma lupa estereoscópia e avaliaram-se o número de anéis, o comprimento da traquéia e da siringe e o comprimento e espessura do músculo traqueolateral. A traquéia do macho apresentou maior número de anéis e maior comprimento que a das fêmeas. O músculo traqueolateral dos machos é mais vigoroso e origina-se no 43º anel traqueal enquanto o das fêmeas origina-se no 30º anel traqueal e se insere no primeiro anel bronquial. A siringe do piriquito é constituída por anéis craniais, cinco nos machos e três nas fêmeas, anéis intermediários, com formato semelhante a uma bolha sulcada ventralmente, anéis caudais, quatro em ambos os sexos, e pessulo. O dimorfismo sexual está presente na morfometria da musculatura e das cartilagens, o que reflete no canto mais vigoroso dos machos

The morphologic differences of the trachea and syrinx of five male and five female Touist sp. parakeets were studied. Trachea and syrinx were dissected with the aid of a stereoscopic magnifying glass and the number of rings, the length of trachea and syrinx were evaluated, as well as the length and thickness of the tracheolateral muscle. Trachea of male parakeets had larger amount of rings and was lengther than the female. Tracheolateral muscle of the males was more vigorous and arised in the 43rd tracheal ring while in the females it originated in the 30th tracheal and inserted in first bronchi ring. The syrinx was constituted by cranial rings (five in males and three in females), intermediate rings (resembly a bubble furrowed ventrally), caudal rings (four in both sexes) and the pessule. Sexual dimorphism directly influenced on the syrinx, concerning the morfometry of the musculature and cartilages, making males sound more vigorously

Dimorfismo sexual da traquéia e siringe de periquito (Touist sp. ) / Sexual dimorphism of the parakeet (Touist sp. ) trachea and syrinx

Investigaram-se as diferenças morfológicas da siringe do periquito Touist sp, cinco machos e cinco fêmeas. A traquéia e a siringe foram dissecadas com o auxílio de uma lupa estereoscópia e avaliaram-se o número de anéis, o comprimento da traquéia e da siringe e o comprimento e espessura do músculo traqueolateral. A traquéia do macho apresentou maior número de anéis e maior comprimento que a das fêmeas. O músculo traqueolateral dos machos é mais vigoroso e origina-se no 43º anel traqueal enquanto o das fêmeas origina-se no 30º anel traqueal e se insere no primeiro anel bronquial. A siringe do piriquito é constituída por anéis craniais, cinco nos machos e três nas fêmeas, anéis intermediários, com formato semelhante a uma bolha sulcada ventralmente, anéis caudais, quatro em ambos os sexos, e pessulo. O dimorfismo sexual está presente na morfometria da musculatura e das cartilagens, o que reflete no canto mais vigoroso dos machos(AU)

The morphologic differences of the trachea and syrinx of five male and five female Touist sp. parakeets were studied. Trachea and syrinx were dissected with the aid of a stereoscopic magnifying glass and the number of rings, the length of trachea and syrinx were evaluated, as well as the length and thickness of the tracheolateral muscle. Trachea of male parakeets had larger amount of rings and was lengther than the female. Tracheolateral muscle of the males was more vigorous and arised in the 43rd tracheal ring while in the females it originated in the 30th tracheal and inserted in first bronchi ring. The syrinx was constituted by cranial rings (five in males and three in females), intermediate rings (resembly a bubble furrowed ventrally), caudal rings (four in both sexes) and the pessule. Sexual dimorphism directly influenced on the syrinx, concerning the morfometry of the musculature and cartilages, making males sound more vigorously(AU)

Morphometric study of Rynchotus rufescens testis throughout the year.

The research aimed to study the morphologic variation of the testis, seeking to promote the selection and genetic control of those that present appreciable spermatic production throughout the year. Testis morphology of the Rynchotus rufescens partridge was investigated, analyzing the testis weight, the seminiferous tubules diameter, the thickness of the seminiferous epithelium, the amount of meiotic figures and the thickness of the tunica albuginea. Sixty male partridges were used, divided in 12 groups, and one group per month had the testis collected for the histological routine and the sections were stained using the Hematoxilin-Eosin technique. For the histological sections analysis, morphometric measures were taken, with the aid of an Image Analyzer and the resulting data were submitted to analysis of variance and to Tukey's test. Based on the histological modifications of the seminiferous epithelium and the morphometric analysis, the partridge testis morphology could be divided in four successive phases throughout the year. The reproductive phase occurred in the spring, characterized by the complete spermatogenesis process. The regression phase occurred in the summer, with the involution of the seminiferous epithelium. The rest phase took place in the fall, with spermatogonias presence and some spermatocytes beginning the meiosis. The phase of recrudescence occurred in the winter, with the recovery of the seminiferous epithelium and absence of spermatozoa. In conclusion, the characteristics analyzed revealed a variation over the year, with greater production of spermatozoa in the spring and less in the winter.

Morphometric study of Rynchotus rufescens testis throughout the year

The research aimed to study the morphologic variation of the testis, seeking to promote the selection and genetic control of those that present appreciable spermatic production throughout the year. Testis morphology of the Rynchotus rufescens partridge was investigated, analyzing the testis weight, the seminiferous tubules diameter, the thickness of the seminiferous epithelium, the amount of meiotic figures and the thickness of the tunica albuginea. Sixty male partridges were used, divided in 12 groups, and one group per month had the testis collected for the histological routine and the sections were stained using the Hematoxilin-Eosin technique. For the histological sections analysis, morphometric measures were taken, with the aid of an Image Analyzer and the resulting data were submitted to analysis of variance and to Tukey's test. Based on the histological modifications of the seminiferous epithelium and the morphometric analysis, the partridge testis morphology could be divided in four successive phases throughout the year. The reproductive phase occurred in the spring, characterized by the complete spermatogenesis process. The regression phase occurred in the summer, with the involution of the seminiferous epithelium. The rest phase took place in the fall, with spermatogonias presence and some spermatocytes beginning the meiosis. The phase of recrudescence occurred in the winter, with the recovery of the seminiferous epithelium and absence of spermatozoa. In conclusion, the characteristics analyzed revealed a variation over the year, with greater production of spermatozoa in the spring and less in the winter.

O trabalho teve como objetivo estudar a variação morfológica do testículo, visando promover a seleção e o controle genético de exemplares que apresentem produção espermática apreciável ao longo do ano. A morfologia testicular de perdiz Rynchotus rufescens foi avaliada, analisando o peso do testículo, o diâmetro dos túbulos seminíferos, a espessura do epitélio seminífero, o número de figuras de meiose e a espessura da túnica albugínea. Foram utilizados 60 machos de perdizes, divididos em 12 grupos, sendo que um grupo por mês teve os testículos coletados para a rotina histológica e foram corados pela técnica de Hematoxilina-Eosina. Para a análise dos cortes histológicos, foram realizadas medidas morfométricas, com o auxílio de um Analisador de Imagem e os dados encontrados foram submetidos à análise de variância e teste de Tukey. Baseado nas modificações histológicas do epitélio seminífero e na análise morfométrica, a morfologia testicular da perdiz pôde ser dividida em quatro fases sucessivas ao longo do ano. A fase reprodutiva ocorreu na primavera, caracterizando-se pelo completo processo de espermatogênese. A fase de regressão aconteceu no verão, ocorrendo involução do epitélio seminífero. No outono ocorreu a fase de repouso, com a presença de espermatogônias e alguns espermatócitos em início de meiose, já a fase de recrudescência da perdiz aconteceu no inverno, com a recuperação do epitélio seminífero e ausência de espermatozóides. Em conclusão, as características analisadas revelaram uma variação durante o ano, com maior produção de espermatozóides na primavera e menor produção no inverno.

Morphometric study of Rynchotus rufescens testis throughout the year

The research aimed to study the morphologic variation of the testis, seeking to promote the selection and genetic control of those that present appreciable spermatic production throughout the year. Testis morphology of the Rynchotus rufescens partridge was investigated, analyzing the testis weight, the seminiferous tubules diameter, the thickness of the seminiferous epithelium, the amount of meiotic figures and the thickness of the tunica albuginea. Sixty male partridges were used, divided in 12 groups, and one group per month had the testis collected for the histological routine and the sections were stained using the Hematoxilin-Eosin technique. For the histological sections analysis, morphometric measures were taken, with the aid of an Image Analyzer and the resulting data were submitted to analysis of variance and to Tukey's test. Based on the histological modifications of the seminiferous epithelium and the morphometric analysis, the partridge testis morphology could be divided in four successive phases throughout the year. The reproductive phase occurred in the spring, characterized by the complete spermatogenesis process. The regression phase occurred in the summer, with the involution of the seminiferous epithelium. The rest phase took place in the fall, with spermatogonias presence and some spermatocytes beginning the meiosis. The phase of recrudescence occurred in the winter, with the recovery of the seminiferous epithelium and absence of spermatozoa. In conclusion, the characteristics analyzed revealed a variation over the year, with greater production of spermatozoa in the spring and less in the winter.

O trabalho teve como objetivo estudar a variação morfológica do testículo, visando promover a seleção e o controle genético de exemplares que apresentem produção espermática apreciável ao longo do ano. A morfologia testicular de perdiz Rynchotus rufescens foi avaliada, analisando o peso do testículo, o diâmetro dos túbulos seminíferos, a espessura do epitélio seminífero, o número de figuras de meiose e a espessura da túnica albugínea. Foram utilizados 60 machos de perdizes, divididos em 12 grupos, sendo que um grupo por mês teve os testículos coletados para a rotina histológica e foram corados pela técnica de Hematoxilina-Eosina. Para a análise dos cortes histológicos, foram realizadas medidas morfométricas, com o auxílio de um Analisador de Imagem e os dados encontrados foram submetidos à análise de variância e teste de Tukey. Baseado nas modificações histológicas do epitélio seminífero e na análise morfométrica, a morfologia testicular da perdiz pôde ser dividida em quatro fases sucessivas ao longo do ano. A fase reprodutiva ocorreu na primavera, caracterizando-se pelo completo processo de espermatogênese. A fase de regressão aconteceu no verão, ocorrendo involução do epitélio seminífero. No outono ocorreu a fase de repouso, com a presença de espermatogônias e alguns espermatócitos em início de meiose, já a fase de recrudescência da perdiz aconteceu no inverno, com a recuperação do epitélio seminífero e ausência de espermatozóides. Em conclusão, as características analisadas revelaram uma variação durante o ano, com maior produção de espermatozóides na primavera e menor produção no inverno.