Transmission electron microscopy for characterization of acrosomal damage after Percoll gradient centrifugation of cryopreserved bovine spermatozoa

The objective of this study was to characterize acrosomal ultrastructure following discontinuous Percoll gradient centrifugation of cryopreserved bovine sperm. Semen was collected from six bulls of different breeds and three ejaculates per bull were evaluated. Frozen semen samples were thawed and the acrosomal region of sperm cells was evaluated by transmission electron microscopy (TEM) before (n = 18) and after (n = 18) Percoll centrifugation. The evaluation of 20 sperm heads from each of the 36 samples analyzed ensured that a large number of cells were investigated. The data were subjected to analysis of variance at a level of significance of 5%. Percoll centrifugation reduced the percentage of sperm exhibiting normal acrosomes (from 61.77 to 30.24%), reduced the percentage of sperm presenting atypical acrosome reactions (from 28.38 to 4.84%) and increased the percentage of sperm exhibiting damage in the acrosome (from 6.14 to 64.26%). The percentage of sperm with typical acrosome reactions was not significantly different before (3.70%) and after (0.67%) centrifugation. TEM distinguished four different types of acrosomal status and enabled ultrastructural characterization of acrosomal injuries. The percentage of sperm exhibiting normal acrosomes decreased and damage in the acrosome was the most frequent acrosomal injury with the Percoll gradient centrifugation protocol utilized

Expanding tropical forest monitoring into Dry Forests: The DRYFLOR protocol for permanent plots

This is the final version. Available on open access from Wiley via the DOI in this recordSocietal Impact Statement Understanding of tropical forests has been revolutionized by monitoring in permanent plots. Data from global plot networks have transformed our knowledge of forests’ diversity, function, contribution to global biogeochemical cycles, and sensitivity to climate change. Monitoring has thus far been concentrated in rain forests. Despite increasing appreciation of their threatened status, biodiversity, and importance to the global carbon cycle, monitoring in tropical dry forests is still in its infancy. We provide a protocol for permanent monitoring plots in tropical dry forests. Expanding monitoring into dry biomes is critical for overcoming the linked challenges of climate change, land use change, and the biodiversity crisis.Newton FundNatural Environment Research Council (NERC)Fundação de Amparo à Pesquisa do Estado de São PauloCYTE

Diversity of arborescent lineages of Crotoneae (Euphorbiaceae) in the Brazilian Atlantic Rain Forest

We conducted fieldwork and herbarium research to investigate the morphological diversity, taxonomy, and geographic distribution of arborescent lineages of tribe Crotoneae (Euphorbiaceae) in the Brazilian Atlantic Rain Forest domain, a neotropical region considered one of the world’s hot spots of biodiversity. We found that arborescent lineages of Crotoneae are represented in the Atlantic Rain Forest by two genera (Croton and Brasiliocroton) and 23 species. Of this total, 70% of the species are endemic to the Atlantic Rain Forest. The genus Brasiliocroton, which is endemic to Brazil, includes two species, and Croton is represented by 21 species. We provide identification keys, update morphological description of key characters, include pertinent taxonomic comments, and illustrate most of the studied species with live photographs to facilitate taxonomic identification. The conservation status of each species is also evaluated. We establish five new synonyms, one superfluous name, and nine lectotypifications.Financial support was provided to MBR Caruzo (process 441049/2014-1) by “Conselho Nacional de Desenvolvimento Científico e Tecnológico” (CNPq).Peer Reviewe

Retenção de placenta e endometrite subclínica: prevalência e relação com o desempenho reprodutivo de vacas leiteiras mestiças

RESUMO: Objetivou-se avaliar os efeitos do tipo de parto (eutócico vs. distócico) e do período do ano (chuvoso vs. seco) sobre a prevalência de retenção de placenta (RP) e de endometrite subclínica (ES), verificar a relação entre as duas patologias, e os efeitos dessas sobre a taxa de descarte, o período de serviço (PS) e número de IA/concepção. A RP foi avaliada no primeiro dia pós-parto (DPP). A citologia endometrial foi realizada entre 30 e 80 DPP, considerando positivos casos contendo acima de 5% de neutrófilos. Os dados foram analisados por regressão logística e análise de variância no programa Minitab (P0,05). Conclui-se que a retenção de placenta tende a ser um fator de risco para endometrite subclínica, distocia predispõe à retenção de placenta e partos ocorridos no período chuvoso aumentam os casos de endometrite subclínica. Há um impacto negativo na eficiência reprodutiva de vacas leiteiras mestiças acometidas por retenção de placenta

Perfil metabólico de vacas mestiças leiteiras com baixo escore de condição corporal no periparto

Objetivou-se avaliar o perfil metabólico energético, proteico e enzimático de vacas mestiças leiteiras com baixo escore de condição corporal (ECC) no periparto. Foram colhidas amostras sanguíneas uma semana antes do parto, no dia do parto, e aos sete, 14, 21, 28 e 43 dias pós-parto (DPP) de 36 animais, com média de ECC de 2,6±0,5, com eutocia e pós-parto fisiológico e sem tratamentos nesta fase. Analisaram-se as concentrações séricas de proteínas totais, albumina e globulinas para o perfil protéico; AST, ALT, GGT e fosfatase alcalina para o perfil enzimático; ácidos graxos não-esterificados (NEFA), β-hidroxibutirato (BHBA), triglicerídeos, colesterol e lipoproteínas (VLDL, HDL e LDL) para o perfil energético. As vacas apresentaram no pré-parto hipoproteinemia, hipoalbuminemia, hipocolesterolemia e aumento das enzimas GGT e AST. No dia do parto houve lipólise e hipoglobulinemia. Concluiu-se que vacas mestiças leiteiras com baixo ECC apresentam balanço energético negativo, hipoproteinemia com hipoalbuminemia e lesão hepática no periparto, com restabelecimento aos 30 DPP, mas não recuperam sua condição corporal até o final do puerpério