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Abstract Estuaries are constantly subject to continuous environmental impacts of human activities, such as fisheries, port or industry, and domestic sewage, with fish being one of the most affected aquatic animals, reflecting the impacts directly on their bodies. Thus, the aim of this study was to carry out the biomonitoring of an estuary located on the Amazonian Equatorial Coast through analysis of PAHs (Polycyclic Aromatic Hydrocarbons) in the water, in addition to trace metals, histopathological alterations and analysis of erythrocyte micronuclei in Sciades herzbergii. S. herzbergii was used as a model species, due to its estuarine-resident behavior. Gonad and gill samples were subjected to histopathological evaluations. The quantification of trace metals was performed in samples of skeletal muscles of the animals collected, where concentrations of Lead (Pb), Copper (Cu), Zinc (Zn), Cadmium (Cd), Magnesium (Mg), Iron (Fe) and Aluminum (Al) were found. Except for Cadmium (Cd), all the concentrations were above the recommended limits. The PAHs analysis revealed the presence of Naphthalene and Acenaphthene in the water samples Histopathological and genotoxic analyses revealed of lesions in 100% of the study specimens. Thus, the histological and genotoxic alterations found in 100% of S. herzbergii specimens captured in São José Bay-MA are potentially associated with PAH concentrations present in the water. These results are potentially associated with the presence of PAH and trace metals, both in water and in animal tissues, inferring a general scenario of environmental contamination which directly implies a risk to the health and survival of the local biota. This study shows the relevance of continuous biomonitoring of estuarine ecosystems, in order to guide authorities regarding sewage management and ensure the evolutionary development of estuarine species, especially fishes of importance in the local cuisine, therefore related to human food security. Resumo Os estuários estão constantemente sujeitos a impactos ambientais de atividades antropogênicas, como pesca, movimentação portuária, indústria ou esgoto doméstico, onde os peixes são um dos animais aquáticos mais atingidos, sendo capazes de refletir os impactos diretamente em seu organismo. Assim, o objetivo desse estudo foi realizar o biomonitoramento de um estuário da Costa Equatorial Amazônica por meio de análises de PAHs (Hidrocarboneto Policiclico Aromáticos) na água, além de metais traços, alterações histopatológicas e análises de micronúcleos eritrocitários em Sciades herzbergii.. O S. herzbergii foi utilizado como espécie modelo, devido seu comportamento estuarino residente. Amostras de gônadas e brânquias foram submetidas a avaliações histopatológicas. A quantificação de metais traços foi realizada em amostras de músculos esqueléticos dos animais coletados, onde foram encontrados teores de Chumbo (Pb), Cobre (Cu), Zinco (Zn), Cádmio (Cd), Magnésio (Mg), Ferro (Fe) e Alumínio (AL), e foram encontradas em concentrações acima dos limites recomendados, à exceção do Cádmio (Cd). A análise dos PAHs revelou a presença de Naftaleno e Acenafteno nas amostras de água. Análises histopatológicas e genotóxicas revelaram lesões em 100% dos espécimes estudados, resultados estes, potencialmente associados à presença de PAH e de metais traços, tanto na água quanto nos tecidos animais, comprovando um cenário geral de contaminação ambiental implicando diretamente em risco à saúde e sobrevivência da biota local. Esse estudo mostra a relevância do biomonitoramento contínuo dos ecossistemas estuarinos, afim de nortear autoridades no manejo de efluentes e assegurar o desenvolvimento evolutivo de espécies estuarinas, sobretudo dos peixes de importância na culinária regional, diretamente relacionados à segurança alimentar humana.

Abstract Peacock bass (Ciclha kelberi) has been introduced in reservoirs in Brazil; however, information about its reproductive aspects and gonadal maturation remains scarce. Studies on this field carried out in Maranhão State, Brazil mainly address information from lakes and specific regions. The aims of the present study are to feature the gonads and female germ cells of C. kelberi captured in a basin by Lençóis Maranhenses National Park. Thirty specimens were collected, euthanized and weighed. Their gonads were subsequently removed and taken to histological processing. Females were classified as synchronous in multiple batches. Germ cells were featured as Primordial Follicles, Primary Development, Cortical Alveoli, Lipid Vitellogenesis, Lipid-Protein Vitellogenesis and Complete Vitellogenesis. Post-ovulatory and Atretic Follicles were also observed. The smallest cell (in diameter) was observed in primordial follicle cells (16.7 µm) and the largest one was recorded for atretic follicle cells (453.5 µm). The smallest cell area was 580.9 µm2 and the largest one was 300,240.7 µm2. The collected data differed from those recorded other reservoirs in Maranhão State and for other locations in Brazil. This finding points out that this species remains under adaption to the lotic environment in Preguiças River, at Lençóis Maranhenses National Park. Additional research is necessary to help better understanding the long-term reproductive and ecological aspects of the assessed species in order to support the sustainable management of this basin. Resumo Ciclha kelberi tem sido introduzido em reservatórios no Brasil e as informações acerca dos aspectos reprodutivos, maturação gonadal da espécie ainda são escassas, No Maranhão, tais estudos se encontram pontuais e restritos às regiões lacustres. O presentetrabalho objetiva caracterizar as gônadas e células germinativas femininas de C. kelberi bacia adjacente ao Parque Nacional dos Lençóis Maranhenses, Brasil. Foram coletados 30 exemplares, estes foram eutanasiados, pesados e posteriormente as gônadas foram retiradas e encaminhadas ao processamento histológico. As fêmeas foram classificadas como sincrônicas em lotes múltiplos. As células germinativas foram caracterizadas como Folículo primordial, Desenvolvimento primário, Alvéolo cortical, Vitelogênese lipídica, Vitelogênese lipídica-proteica e Vitelogênese completa. Também foram observados Folículos Pós-ovulátorios e Atrésicos. O menor diâmetro celular foi em células de folículo primordial 16.7 µm e o maior em folículo atrésico 453.5 µm. A menor área celular foi de 580.9 µm2 e a maior 300.240,7 µm2. Os dados observados no presente trabalho diferem de outros observados em demais reservatórios observados no Maranhão e em outros estados do Brasil, demonstrando que a espécie está em processo de adaptação ao ambiente lótico do Rio Preguiças, no Parque Nacional dos Lençóis Maranhenses. Pesquisas adicionais são necessárias para compreender a longo prazo os aspectos reprodutivos e ecológicos da espécie a fim auxiliar no manejo sustentável da bacia.

Abstract The objective of the present study was to characterize non-classical class I major histocompatibility complex (MHC) genes in buffaloes and evaluate the expression of these genes in different tissue components of the placenta of buffaloes during pregnancy and in trophoblastic cells after stimulation using lipopolysaccharide (LPS). To do this, DNA was extracted from the blood of buffaloes and was subjected to PCR testing and sequencing of the genes NC3 and MICB. The RNA extracted from the placentome and intercotyledonary region of buffaloes in their first (n = 6), second (n = 6) and third (n = 6) trimesters of gestation was subjected to real-time PCR. Explants were created using the chorioallantoic membrane and two experimental groups were established: control and stimulated with LPS for four hours to evaluate the gene expression profile. Analysis on the sequences obtained showed that the genes NC3 and MICB of buffaloes were homologous with those of cattle, with high similarity in the analysis on the sequence variation pattern. The gene expression analysis showed that the genes assessed were transcribed at stages and in placental tissue that differed from what was seen in cattle. The transcription of these genes varied in the tissues studied, with greater transcription of MICB in the intercotyledonary region over the first third of gestation, while the genes studied in the placentome presented low rates of transcription. The trophoblastic cells of the chorioallantoic membrane stimulated with LPS for six hours did not present non-classic MFC-I transcription alterations. The present study therefore provides additional knowledge regarding the immune regulation of placental tissues of buffaloes. Resumo O objetivo do presente estudo foi caracterizar genes não clássicos do complexo principal de histocompatibilidade (MHC) de classe I em búfalas e avaliar a expressão desses genes em diferentes componentes teciduais da placenta de búfalas durante a gestação e em células trofoblásticas após estimulação com lipopolissacarídeo (LPS). Para isso, o DNA foi extraído do sangue de búfalos e submetido a testes de PCR e sequenciamento dos genes NC3 e MICB. O RNA extraído do placentônio e região intercotiledonar de búfalas no primeiro (n = 6), segundo (n = 6) e terceiro (n = 6) trimestres de gestação foi submetido à PCR em tempo real. Explantes foram criados usando a membrana corioalantóide e dois grupos experimentais foram estabelecidos: controle e estimulado com LPS por quatro horas para avaliar o perfil de expressão gênica. A análise das sequências obtidas mostrou que os genes NC3 e MICB de búfalos foram homólogos aos de bovinos, com alta similaridade na análise do padrão de variação de sequência. A análise da expressão gênica mostrou que os genes avaliados foram transcritos em estágios e em tecido placentário diferentes do observado em bovinos. A transcrição desses genes variou nos tecidos estudados, com maior transcrição de MICB na região intercotiledonar ao longo do primeiro terço da gestação, enquanto os genes estudados no placentoma apresentaram baixas taxas de transcrição. As células trofoblásticas da membrana corioalantóide estimuladas com LPS por seis horas não apresentaram alterações não clássicas na transcrição da MFC-I. O presente estudo, portanto, fornece conhecimento adicional sobre a regulação imune de tecidos placentários de búfalos.

Two experiments were designed to evaluate the impact of puberty status and the administration of melengestrol acetate (MGA) before onset of the breeding period on ovulatory responses (Exp. 1) and conception rate after AI performed on estrus detection during 10 d and the pregnancy rate through 80 d of breeding period (Exp. 2) of pasture-grazed beef heifers. In Exp. 1, heifers (15 pubertal and 15 prepubertal) received 0.5 mg per heifer/d -1 of MGA over 14 d. No differences in the ovulatory responses were found 10 d after the MGA administration (pubertal = 46.7% vs. prepubertal P = 53.3%; P = 0.72). In Exp. 2, 368 heifers were randomly assigned to groups according to pubertal status and the MGA treatment. All heifers were inseminated on estrus detection for up 10 d after MGA administration and following exposure to bulls between 20 and 80 d. The MGA-treated heifers exhibited a greater AI service rate than control heifers (72.1 vs. 41.6%;P < 0.01); however, heifers receiving MGA had lower conception results following AI (51.6 vs. 71.4%; P = 0.01). In addition, MGA-treated heifers were more likely to have a corpus luteum in the middle of the breeding period (95.3 vs. 87.5%;P < 0.01), although the Cox proportional hazard of pregnancy rate was similar (P = 0.29) at the end of the breeding period. At onset of the breeding period, pubertal heifers presented a greater pregnancy rate following AI (pubertal P = 42.2% vs. prepubertal P = 24.9%; P = 0.01). Therefore, pubertal heifers seem to have greater overall reproductive efficiency than prepubertal heifers, particularly at the beginning of the breeding period. Interestingly, administration of MGA before the onset of the breeding period increased AI service rate but did not alter the rate of pregnancy throughout the breeding period of pasture-grazed beef heifers.

Abstract The aim of the current study is to evaluate gene expression patterns of LH (lhr) and estrogen (er) receptors and plasma steroid levels during testicular development in Genyatremus luteus. Males were histologically classified as immature (n=7), maturing (n=7) and mature (n=7), based on the cellular structure of their testes. Plasma 11-KT concentration recorded peak at the final maturation stage. The highest plasma 17α-OHP concentrations were observed at the immature stage; they decreased at the maturation and mature stages. On the other hand, 17β-estradiol (E2) recorded higher concentrations at the maturation stage. Er expression has significantly increased along the maturational development of animals’ testes. The mRNA observed for the LH receptor has decreased from immature to maturing stage; it presented expression peak at the mature stage. There was high association between receptor gene expression and plasma steroid levels, mainly E2. The current study was the first to feature different reproductive maturation stages in male G. luteus specimens, based on cellular, endocrine and molecular aspects. In addition, it has shown that the gene expression profile for er and lhr receptors, as well as plasma 11-KT and E2 concentrations, are directly linked to testicular maturation, although they are not necessarily associated with the gonadosomatic index. Resumo O objetivo deste estudo foi avaliar os padrões de expressão gênica dos receptores de LH (lhr) e de estrogênio (er) e dos níveis de esteróides plasmáticos durante o desenvolvimento testicular de Genyatremus luteus. Os machos foram classificados histologicamente em imaturos, em maturação e maduros, de acordo com a estrutura celular dos testículos. A concentração plasmática de 11-KT apresentou um pico na fase de maturação final (P<0.05). As maiores concentrações plasmáticas de 17α-OHP foram encontradas no estádio imaturo (P<0.05), com consequente diminuição nos estádios em maturação e maturo. O 17β-estradiol (E2) apresentou maiores níveis de concentração no estádio em maturação (P<0.05). A expressão de er aumentou significativamente ao longo do desenvolvimento maturacional dos testículos (P<0.05). O mRNA para o receptor de LH diminuiu do estádio imaturo para o estádio em maturação (P<0.05) com consequente pico de expressão no estádio maduro. Houve alta relação entre a expressão gênica dos receptores e os níveis de esteróides plasmáticos, especialmente com E2. Em conclusão, este estudo caracterizou pela primeira vez, sob os aspectos celular, endócrino e molecular, os diferentes estádios de maturação reprodutiva em machos de G. luteus, demonstrando que o perfil da expressão gênica para os receptores er e lhr, bem como as concentrações plasmáticas de 11-KT e E2 foram diretamente relacionados à maturação testicular, apesar de não se relacionarem necessariamente com o índice gonadossomático.

The current study aimed to evaluate the effects of cactus pear as a moistening additive on fermentative and microbiological characteristics, aerobic stability (AS), chemical composition and in situ rumen degradability of corn grain silage at different opening times. A completely randomized experimental design was adopted in a 4 × 3 factorial scheme with four levels of dry matter (DM) (50; 60; 70 and 80% of DM) and three opening times (30; 60 and 120 days after ensiling), with four replications. There was an effect of interaction (P < 0.05) between the DM levels and opening times on silage yeast population, effluent losses, gas losses, dry matter recovery (DMR), AS of the silage and on lactic acid bacteria, mould and yeast populations after AS trial. The 60% DM level presented DMR values above 930 g/kg of DM. However, the lowest AS time (96.52 h) was observed in silages with 60% DM at 60 days after ensiling, although all silages have shown high AS. The DM in situ degradability of the ensiled mass increased after the ensiling process at all DM levels and opening times, with the 60% DM content showing the best result. When using cactus pear as a corn grain moistening additive, the 60% DM level is recommended when the opening time is up 120 days.

Application of the plant growth regulator paclobutrazol (PBZ) to aid floral induction has been widely performed by mango producers. However, its application has been done manually, resulting in low uniformity of application and losses with labor. The objective of this study was to adjust the PBZ dose to be applied via micro-sprinkler system for floral induction, indicating an efficient management of ?Palmer? mango in the Brazilian semi-arid region. The experiment was conducted at Saúde Farm, located in Petrolina-PE, Brazil, starting in October 2015, with harvests in June 2016 and 2017. The experimental design used was randomized blocks, with five doses of PBZ, applied via irrigation system (T1 - 0.56; T2 - 1.12; T3 -1.68; T4 - 2.24; and T5 - 2.80 g a.i. linear m-1 canopy) and a conventionally applied dose (T0 - 2.80 g a.i. linear m-1 of canopy, manually applied broadcast), with four replicates. The variables analyzed were: CO2 assimilation, stomatal conductance, transpiration, leaf temperature, number and length of panicles, number of fruits per plant, average fruit weight, yield, pulp firmness, titratable acidity and total soluble solids in the fruits. At the conventionally applied dose (2.8 g a.i. linear m-1 of canopy), PBZ application via micro-sprinkler irrigation system proved to be the most efficient way to reduce CO2 assimilation, stomatal conductance and transpiration. PBZ applied via micro-sprinkler irrigation system at a dose of 0.56 g a.i. linear m-1 of canopy promotes greater number of panicles and yield in ?Palmer? mango.

O objetivo do presente trabalho foi avaliar a influência de lâminas de irrigação e doses de bioestimulante sobre a produção e pós-colheita do melão amarelo Gladial F1, em diferentes períodos do ano. O manejo da irrigação associado à utilização de bioestimulantes vem sendo empregado em diversas culturas agrícolas para aumentar seu desempenho agronômico, assim seu emprego pode representar uma alternativa promissora no cultivo do meloeiro em regiões semiáridas do nordeste brasileiro.

This study aimed to assess the impact of adding forage cactus as an additive to the production of corn silage without the cob on the performance of feedlot sheep and subsequent silage losses. The experimental design was completely randomized, consisting of three treatments: corn silage without cob; 0% = 100% corn plant without the cob; 10% = 90% corn plant without cob + 10% forage cactus; 20% = 80% corn plant without cob + 20% forage cactus. Significant effects were observed for dry matter intake ( P  = 0.0201), organic matter ( P  = 0.0152), ether extract ( P  = 0.0001), non-fiber carbohydrates ( P  = 0.0007). Notably, nutrient digestibility showed significant differences in organic matter ( P  = 0.0187), ether extract ( P  = 0.0095), neutral detergent fiber ( P  = 0.0005), non-fiber carbohydrates ( P  = 0.0001), and metabolizable energy ( P  = 0.0001). Performance variables, including total weight gain ( P  = 0.0148), average daily weight gain ( P  = 0.0148), feeding efficiency, and rumination efficiency of dry matter ( P  = 0.0113), also exhibited significant effects. Consequently, it is recommended to include 20% forage cactus in corn silage, which, based on natural matter, helps meet animals’ water needs through feed. This inclusion is especially vital in semi-arid regions and aids in reducing silage losses during post-opening silo disposal.