Metabolic stress and reproductive features in post-partum goats supplemented for a long period with detoxified castor meal as the source of dietary nitrogen / Estresse metabólico e características reprodutivas em cabras pós-parto suplementadas por longo período com mamona desintoxicada como fonte de nitrogênio na dieta

This study evaluated the effect of detoxified castor meal on the reproductive performance, metabolic stress, milk production, and kid development in peripartum goats. The diet of the animals were with (DCM, n= 20) or without (WDCM, n= 21) detoxified castor meal during the entire gestation and until weaning, 60 days post-birth. No differences were observed in the gestation period, litter size, rate of multiple births, and mortality between the two groups. The postpartum plasma concentrations of progesterone remained below 1ng/mL in all animals, thus, confirming the absence of active corpora lutea. The thickness of sternum adipose tissue and loin area, levels of urea and cholesterol, milk production, and daily weight gain in the kids were low in the DCM group when compared to those in the WDCM group (P< 0.05). To conclude, the use of detoxified castor meal in peripartum goats resulted in lower level of performance in the kids because of reductions in the amount of milk received from their mothers during lactation. In addition, the diet containing detoxified castor meals was not efficient in recovering from the loss of stored body reserves able to initiate the recovery of the cyclic activity of the goats.(AU)

Este estudo avaliou o efeito da torta de mamona desintoxicada na reprodução, no estresse metabólico, na produção de leite e no desenvolvimento de cabritos no periparto de cabras. Um grupo foi alimentado com torta de mamona (DCM, n=20), e o outro (WDCM, n=21) não recebeu tal suplemento , durante a gestação até o desmame, 60 dias pós-parto. Não foram observadas diferenças significativas no período de gestação, no número de cabritos, na taxa de partos múltiplos e na mortalidade entre os dois grupos. Em todos os animais, a concentração plasmática de progesterona ficou abaixo de 1ng/mL, confirmando a ausência de atividade lútea. A espessura da gordura subcutânea do esterno e da área de olho-de-lombo, a concentração de ureia e colesterol, a produção de leite e o ganho de peso dos cabritos foram menores no grupo DCM (P<0,05). Conclui-se que o uso de torta de mamona desintoxicada no periparto de cabra resultou em cabritos mais leves devido à redução na produção de leite das matrizes e as cabras não retornaram ao cio, pois não recuperaram a massa corporal.(AU)

Metabolic stress and reproductive features in post-partum goats supplemented for a long period with detoxified castor meal as the source of dietary nitrogen / Estresse metabólico e características reprodutivas em cabras pós-parto suplementadas por longo período com mamona desintoxicada como fonte de nitrogênio na dieta

This study evaluated the effect of detoxified castor meal on the reproductive performance, metabolic stress, milk production, and kid development in peripartum goats. The diet of the animals were with (DCM, n= 20) or without (WDCM, n= 21) detoxified castor meal during the entire gestation and until weaning, 60 days post-birth. No differences were observed in the gestation period, litter size, rate of multiple births, and mortality between the two groups. The postpartum plasma concentrations of progesterone remained below 1ng/mL in all animals, thus, confirming the absence of active corpora lutea. The thickness of sternum adipose tissue and loin area, levels of urea and cholesterol, milk production, and daily weight gain in the kids were low in the DCM group when compared to those in the WDCM group (P< 0.05). To conclude, the use of detoxified castor meal in peripartum goats resulted in lower level of performance in the kids because of reductions in the amount of milk received from their mothers during lactation. In addition, the diet containing detoxified castor meals was not efficient in recovering from the loss of stored body reserves able to initiate the recovery of the cyclic activity of the goats.(AU)

Este estudo avaliou o efeito da torta de mamona desintoxicada na reprodução, no estresse metabólico, na produção de leite e no desenvolvimento de cabritos no periparto de cabras. Um grupo foi alimentado com torta de mamona (DCM, n=20), e o outro (WDCM, n=21) não recebeu tal suplemento , durante a gestação até o desmame, 60 dias pós-parto. Não foram observadas diferenças significativas no período de gestação, no número de cabritos, na taxa de partos múltiplos e na mortalidade entre os dois grupos. Em todos os animais, a concentração plasmática de progesterona ficou abaixo de 1ng/mL, confirmando a ausência de atividade lútea. A espessura da gordura subcutânea do esterno e da área de olho-de-lombo, a concentração de ureia e colesterol, a produção de leite e o ganho de peso dos cabritos foram menores no grupo DCM (P<0,05). Conclui-se que o uso de torta de mamona desintoxicada no periparto de cabra resultou em cabritos mais leves devido à redução na produção de leite das matrizes e as cabras não retornaram ao cio, pois não recuperaram a massa corporal.(AU)

Survival, growth, and hormone production in vitro from preantral follicles of crossbred female goats (Saanen × Anglo-Nubian)

The present study aimed to evaluate the survival, growth, antrum formation, oocyte extrusion, and hormone production during in vitro culture of caprine preantral follicles isolated from pure-breed (Saanen) or crossbreed (F1 generation: ½ Saanen + ½ Anglo-Nubian) goats. Secondary follicles (diameter: 150-250 µm) from Saanen or crossbreed (Saanen × Anglo-Nubian) goats were isolated from the ovarian cortex by microdissection and cultured in vitro for 18 days in α-modified minimum essential medium (α-MEM+) supplemented with vascular endothelial growth factor and increasing concentrations of follicle-stimulating hormone. Every six days follicular morphology, growth, antrum formation, and follicular extrusion were evaluated. In addition, on days 2, 6, 12, and 18 of culture the medium samples were collected and stored at -20°C for further measurement of estradiol and progesterone. The follicular survival, antrum formation, and oocyte extrusion were analyzed by the Chi square test. Follicular diameter and hormone assays were compared using the Kruskal-Wallis test. Survival rates, growth, antral follicle formation, and oocyte extrusion of preantral follicles cultured in vitro were similar between the different genetic groups. The production of estradiol and progesterone indicated the maintenance of cell viability throughout the culture. In conclusion, preantral follicles from pure-breed or crossbreed goats can be used with the same efficiency for in vitro culture of isolated caprine preantral follicles.

Survival, growth, and hormone production in vitro from preantral follicles of crossbred female goats (Saanen × Anglo-Nubian)

The present study aimed to evaluate the survival, growth, antrum formation, oocyte extrusion, and hormone production during in vitro culture of caprine preantral follicles isolated from pure-breed (Saanen) or crossbreed (F1 generation: ½ Saanen + ½ Anglo-Nubian) goats. Secondary follicles (diameter: 150-250 µm) from Saanen or crossbreed (Saanen × Anglo-Nubian) goats were isolated from the ovarian cortex by microdissection and cultured in vitro for 18 days in α-modified minimum essential medium (α-MEM+) supplemented with vascular endothelial growth factor and increasing concentrations of follicle-stimulating hormone. Every six days follicular morphology, growth, antrum formation, and follicular extrusion were evaluated. In addition, on days 2, 6, 12, and 18 of culture the medium samples were collected and stored at -20°C for further measurement of estradiol and progesterone. The follicular survival, antrum formation, and oocyte extrusion were analyzed by the Chi square test. Follicular diameter and hormone assays were compared using the Kruskal-Wallis test. Survival rates, growth, antral follicle formation, and oocyte extrusion of preantral follicles cultured in vitro were similar between the different genetic groups. The production of estradiol and progesterone indicated the maintenance of cell viability throughout the culture. In conclusion, preantral follicles from pure-breed or crossbreed goats can be used with the same efficiency for in vitro culture of isolated caprine preantral follicles.(AU)

Sphingosine 1-phosphate promotes activation of aprine preantral follicle in vitro / Esfingosina 1-fosfato promove ativação de folículos pré-antrais de caprinos in vitro

This study describes the effect of sphingosine 1-phosphate (S1P) for development of preantral follicle, therefore the activation and follicular viability of caprine follicles cultured in vitro. Ovarian fragments were cultured for 1 or 7 days in Minimum Essential Medium with different S1P concentrations (0, 1, 10, 50, 100 or 200ng/mL). All ovarian fragments were processed for histological analysis in optical microscopy, transmission electron microscopy and fluorescence analysis. The treatment using 1ng/mL of S1P was able to maintain the percentage of normal follicles with the progression of the culture from day 1 to 7. At end of the 7-day culture period there was a significant reduction (P<0.05) in the percentage of primordial follicles in all groups treated with S1P, compared with fresh control (FC) and Control Culture (CC), which was followed by an increase of activated follicles (intermediary, primary and secondary). In addition, the culture for 7 days with media supplemented with S1P with 1ng/mL preserved the ultrastructure of organelles and kept the preantral follicular viability when evaluated by fluorescence microscopy. In conclusion, after 7 days of culture, the 1ng/mL of S1P activates the development of preantral caprine follicles, cultured in situ and maintains the oocitary and follicular viability.(AU)

Este estudo descreve o efeito da esfingosina 1-fosfato (S1P) no desenvolvimento de folículos pré-antrais, portanto da ativação e viabilidade de folículos caprinos cultivados in vitro. Fragmentos de ovários foram cultivados por um ou sete dias em meio essencial mínimo com diferentes concentrações de S1P (0, 1, 10, 50, 100 ou 200ng/mL). Os fragmentos de ovário foram processados para análise histológica em microscopia óptica, microscopia eletrônica e microscopia de fluorescência. O tratamento usando 1ng/mL de S1P foi capaz de manter a porcentagem de folículos normais durante o período de cultivo de sete dias. Ao final do período de cultivo, houve uma redução significativa (p<0,05) na porcentagem de folículos primordiais em todos os grupos tratados com S1P, comparados com os grupos controle (FC e CC), seguida por um aumento do número de folículos ativados (intermediários, primários e secundários). Adicionalmente, na cultura por sete dias com meio suplementado com S1P (1ng/mL), houve preservação da ultraestrutura das organelas e manteve-se a viabilidade dos folículos pré-antrais avaliados por microscopia de fluorescência. Em conclusão, após sete dias de cultura, o meio suplementado com 1ng/mL de S1P ativa o desenvolvimento de folículos pré-antrais de caprino, cultivados in situ e mantém as viabilidades oocitária e folicular.(AU)

Transforming growth factor-β (TGF-β) maintains follicular ultrastructure and stimulates preantral follicle growth in caprine ovarian tissue cultured in vitro / Fator de crescimento transformante-β (TGF-β) mantém a ultraestrutura folicular e estimula o crescimento de folículos pré-antrais caprinos inclusos em tecido ovariano cultivado in vitro

The objectives of this study were to investigate whether TGF-β affect the survival, activation and further growth of goat primordial follicles enclosed in ovarian cortex after in vitro culture. Goat ovaries were collected from an abattoir and pieces of ovarian tissues were cultured for one or seven days in a supplemented alpha Minimum Essential Medium, alone or containing TGF-β (1, 5, 10 or 50ng/mL). Ovarian tissues from the fresh control as well as those cultured were processed for histological and ultrastructural studies. The results showed that when compared with fresh control, there was decrease in the percentages of histologically normal follicles in all treatments only after seven days culture. TGF-β did not affect the activation of preantral follicles regardless of its concentration, however, larger follicles diameter (P<0.05) was observed using 10ng/mL TGF-β than in the fresh control and other treatments. Moreover, this concentration maintained the normal ultrastructure after seven days of culture. In conclusion, TGF-β showed additional effect on the follicle growth and the maintenance of ultrastructural integrity of goat preantral follicles enclosed in ovarian tissue when used at 10ng/mL during seven days of culture.(AU)

O objetivo desse estudo foi investigar se o TGF-β afeta a sobrevivência, ativação e crescimento de folículos primordiais caprinos inclusos no córtex ovariano após o cultivo in vitro. Ovários de cabras foram coletados em abatedouro e fragmentos de tecido ovariano foram cultivados por um e sete dias em meio essencial mínimo alfa (α-MEM+) sozinho ou suplementado com TGF-β (1, 5, 10 ou 50ng/mL). Fragmentos ovarianos não cultivados e cultivados foram processados para análise histológica e ultraestrutural. Os resultados mostraram que, comparado ao controle fresco, houve diminuição no percentual de folículos morfologicamente normais em todos os tratamentos somente após sete dias de cultivo. O TGF-β não afetou a ativação folicular independente da concentração testada, contudo, o diâmetro folicular foi superior (P<0.05) no tratamento com 10ng/mL de TGF-β quando comparado ao controle fresco e aos demais tratamentos. Além disso, essa mesma concentração manteve a ultraestrutura normal dos folículos após sete dias de cultivo. Em conclusão, o TGF-β apresentou efeito adicional no crescimento folicular e na manutenção da integridade ultraestrutural de folículos pré-antrais caprinos inclusos no tecido ovariano quando utilizado na concentração de 10ng/mL durante sete dias de cultivo.(AU)

FSH and LH enhance the development of goat preantral follicles cultured in vitro

This study evaluated th e effect of increased follicle stimulating hormone (FSH) concentrations on the expression of mRNA for LH receptors after in vitro culture of goat preantral follicles ( ≥ 150 μm) for 18 days. It also investigated whether the addition of luteinizing hormone (LH) to the culture medium, which contained increasing concentrations of FSH throughout the culture period, influenced the surv ival, growth and antrum formation of in vitro cultured goat preantral follicles. In experiment 1, preantral follicles were cultured in α -MEM + or α -MEM + supplemented with increasing concentrations of FSH throughout the culture period (sequential medium: FSH 100 ng/ml (days 0 to 6), FSH 500 ng/ml (days 6 to 12) and FSH 1000 ng/ml (days 12 to 18). The expression of luteinizing hormone receptor (LHR) was analyzed in noncultured and cultured follicles using real time RT-PCR. In experiment 2, isolated preantral follicles were cultured for 18 days in a sequential medium containing FSH (control) or a control medium supplemented with LH (50 or 100 ng/ml) from day 12 of culture onwards. Follicle development was evaluated on the basis of antr al cavity formation as well as follicular and oocyte growth after in vitro maturation. FSH stimulated a significant increase in the expression of mRNA for LH receptors after 18 days of culture. Furthermore, after 18 days, all tested media promoted follicular survival and antrum formation; however, a significant increase in the rate of follicular growth and resumption of meiosis was ob served when LH was used compared to the control. In conclusion, preantral follicles cultured in a medium supplemented with FSH increased LH receptor mR NA levels. Moreover, the addition of LH to the culture medium containing increasing concentrations of FSH (sequential medium) improved the in vitro development of goat preantral follicles.

FSH and LH enhance the development of goat preantral follicles cultured in vitro

This study evaluated th e effect of increased follicle stimulating hormone (FSH) concentrations on the expression of mRNA for LH receptors after in vitro culture of goat preantral follicles ( ≥ 150 μm) for 18 days. It also investigated whether the addition of luteinizing hormone (LH) to the culture medium, which contained increasing concentrations of FSH throughout the culture period, influenced the surv ival, growth and antrum formation of in vitro cultured goat preantral follicles. In experiment 1, preantral follicles were cultured in α -MEM + or α -MEM + supplemented with increasing concentrations of FSH throughout the culture period (sequential medium: FSH 100 ng/ml (days 0 to 6), FSH 500 ng/ml (days 6 to 12) and FSH 1000 ng/ml (days 12 to 18). The expression of luteinizing hormone receptor (LHR) was analyzed in noncultured and cultured follicles using real time RT-PCR. In experiment 2, isolated preantral follicles were cultured for 18 days in a sequential medium containing FSH (control) or a control medium supplemented with LH (50 or 100 ng/ml) from day 12 of culture onwards. Follicle development was evaluated on the basis of antr al cavity formation as well as follicular and oocyte growth after in vitro maturation. FSH stimulated a significant increase in the expression of mRNA for LH receptors after 18 days of culture. Furthermore, after 18 days, all tested media promoted follicular survival and antrum formation; however, a significant increase in the rate of follicular growth and resumption of meiosis was ob served when LH was used compared to the control. In conclusion, preantral follicles cultured in a medium supplemented with FSH increased LH receptor mR NA levels. Moreover, the addition of LH to the culture medium containing increasing concentrations of FSH (sequential medium) improved the in vitro development of goat preantral follicles.(AU)

Influência dos hormônios esteroides na foliculogênese / Influence of steroid hormones on folliculogenesis

Os hormônios esteroides estão diretamente relacionados com o processo de foliculogênese, o qual é bastante complexo e influenciado também por vários fatores de crescimento e por hormônios. Diversos estudos demonstraram a importância dos esteroides no desenvolvimento folicular, na maturação oocitária, bem como na formação do corpo lúteo. Desta forma, o objetivo da presente revisão foi sintetizar o processo de formação e o mecanismo de ação dos hormônios esteroides na foliculogênese, com ênfase no estradiol, na progesterona e nos andrógenos.(AU)

Steroid hormones are directly related to the folliculogenesis process, which is very complex and also influenced by several growth factors and hormones. Several studies have demonstrated the importance of steroids in follicular development in mature oocytes as well as corpus luteum formation. The objective of this review is to address the process of synthesis and mechanism of action of steroid hormones in folliculogenesis, with emphasis on estradiol, progesterone and androgens.(AU)

Influência dos hormônios esteroides na foliculogênese / Influence of steroid hormones on folliculogenesis

Os hormônios esteroides estão diretamente relacionados com o processo de foliculogênese, o qual é bastante complexo e influenciado também por vários fatores de crescimento e por hormônios. Diversos estudos demonstraram a importância dos esteroides no desenvolvimento folicular, na maturação oocitária, bem como na formação do corpo lúteo. Desta forma, o objetivo da presente revisão foi sintetizar o processo de formação e o mecanismo de ação dos hormônios esteroides na foliculogênese, com ênfase no estradiol, na progesterona e nos andrógenos.

Steroid hormones are directly related to the folliculogenesis process, which is very complex and also influenced by several growth factors and hormones. Several studies have demonstrated the importance of steroids in follicular development in mature oocytes as well as corpus luteum formation. The objective of this review is to address the process of synthesis and mechanism of action of steroid hormones in folliculogenesis, with emphasis on estradiol, progesterone and androgens.

Androstenedione and follicle stimulating hormone involvement in the viability and development of goat preantral follicles in vitro

This study investigated the effects of androstenedione and follicle-stimulating hormone (FSH) on the viability and growth of caprine preantral follicles. Ovarian tissues were cultured for 1 or 7 days in Minimum. Essential Medium (MEM) containing androstenedione (0, 1, 10, 50 or 100 ng/ml). FSH (50 ng/ml), or a combination of these two hormones. Cultured and non-cultured control tissues were processed for histological and fluorescence analysis. In comparison with non-cultured control, a sinfnificant reduction was noted in the percentage of normal follicles in all treatments after 1 and 7 days of culture (except in all treatment with 1 ng/ml of androstenedione for 1 day). As the culture period progressed from 1 to 7 days, treatments with 10 ng/ml of androstenedione + FSH or 50 ng/ml of androstenedione alone maintained the percentage of normal follicles. After 1 day, treatments with 10, 50, or 100 ng/ml of androstenedione + FSH, or with 50 ng/ml of androstenedione alone had more developing follicles than fresh control tissue. When comparing the culture periods, treatments with 1, 10 or 100 ng/ml of androstenedione alone, or FSH alone, or FSH with 1 ng/ml of androstenedione, showed an increase in the percentage of developing follicles. After 1 and 7 days, there were no differences in oocyte and follicular diameter among the treated samples and non-cultured control or MEM+ cultured tissue. Fluorescence analysis demonstrated that only fragments cultured in 50 or 100 ng/ml of androstenedione + FSH had viable preantral follicles similar to those observed in MEM+ alone. In conclusion, androstenedione at 50 or 100 ng/ml, either associated with FSH or at 50 ng/ml alone, plays an important role in the maintenance of caprine preantral follicle viability and activation after only a short in vitro culture period. In addition, after 7 days MEM+ alone was efficient in the maintenance of viability and in follicular activation, showing the importance of basic medium composition.(AU)

Androstenedione and follicle stimulating hormone involvement in the viability and development of goat preantral follicles in vitro

This study investigated the effects of androstenedione and follicle-stimulating hormone (FSH) on the viability and growth of caprine preantral follicles. Ovarian tissues were cultured for 1 or 7 days in Minimum. Essential Medium (MEM) containing androstenedione (0, 1, 10, 50 or 100 ng/ml). FSH (50 ng/ml), or a combination of these two hormones. Cultured and non-cultured control tissues were processed for histological and fluorescence analysis. In comparison with non-cultured control, a sinfnificant reduction was noted in the percentage of normal follicles in all treatments after 1 and 7 days of culture (except in all treatment with 1 ng/ml of androstenedione for 1 day). As the culture period progressed from 1 to 7 days, treatments with 10 ng/ml of androstenedione + FSH or 50 ng/ml of androstenedione alone maintained the percentage of normal follicles. After 1 day, treatments with 10, 50, or 100 ng/ml of androstenedione + FSH, or with 50 ng/ml of androstenedione alone had more developing follicles than fresh control tissue. When comparing the culture periods, treatments with 1, 10 or 100 ng/ml of androstenedione alone, or FSH alone, or FSH with 1 ng/ml of androstenedione, showed an increase in the percentage of developing follicles. After 1 and 7 days, there were no differences in oocyte and follicular diameter among the treated samples and non-cultured control or MEM+ cultured tissue. Fluorescence analysis demonstrated that only fragments cultured in 50 or 100 ng/ml of androstenedione + FSH had viable preantral follicles similar to those observed in MEM+ alone. In conclusion, androstenedione at 50 or 100 ng/ml, either associated with FSH or at 50 ng/ml alone, plays an important role in the maintenance of caprine preantral follicle viability and activation after only a short in vitro culture period. In addition, after 7 days MEM+ alone was efficient in the maintenance of viability and in follicular activation, showing the importance of basic medium composition.

Sintomas de deficiências nutricionais em cupuaçuzeiro (Theobroma grandiflorum) cultivado em solução nutritiva

With the objective of obtaining the visual symptoms of cupuaçu nutricional deficiencies, seedlings were grown in a greenhouse, in nutrient solution, omitting N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn, in comparison to a complete treatment. All symptoms were described and presented as an identification table, which shows great similarity with cocoa plants. To asses nutrient concentrations, leaves were collected at different parts of the plants, in two samplings. Concentrations found in leaves from plants in which an dement was omitted were always lower than those found in the complete treatment, thereby demonstrating that the symptoms were really due to the induced deficiency. Although the mineral contents of leaves with deficiency symptoms were always lower than those found in other samplings, the reference leaf, recommended in the literature for cocoa (3rd leaf starting from tip), was also adequate for cupuaçu, except in the case of Cu.

Com a finalidade de induzir os sintomas visuais de deficiência nutricional no cupuaçuzeiro, realizou-se em casa de vegetação, um experimento com solução nutritiva onde omitiu-se os seguintes elementos: N, P, K, Ca, Mg, S, B, Cu, Fe, Mu e Zn. Um tratamento completo serviu de comparação. Todos os sintomas foram caracterizados e apresentaram semelhanças com os observados para o cacaueiro, sendo relacionados em tabela para a identificação. Para determinar as concentrações de nutrientes, foram coletadas folhas em diversas partes da planta e em duas épocas de amostragem. Os teores encontrados nas folhas em que o elemento foi omitido foram sempre inferiores daqueles encontrados no tratamento completo, demonstrando que os sintomas descritos foram realmente devidos ao efeito da omissão. Embora os teores apresentados nas folhas com sintomas de deficiência tenham sido sempre menores que os obtidos nas demais amostragens, a folha de referência indicada pela literatura para o cacaueiro (3ª a partir do ápice), mostrou-se adequada para identificar deficiências nutricionais no cupuaçuzeiro, exceto para o cobre.

Sintomas de deficiências nutricionais em cupuaçuzeiro (Theobroma grandiflorum) cultivado em solução nutritiva

With the objective of obtaining the visual symptoms of cupuaçu nutricional deficiencies, seedlings were grown in a greenhouse, in nutrient solution, omitting N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn, in comparison to a complete treatment. All symptoms were described and presented as an identification table, which shows great similarity with cocoa plants. To asses nutrient concentrations, leaves were collected at different parts of the plants, in two samplings. Concentrations found in leaves from plants in which an dement was omitted were always lower than those found in the complete treatment, thereby demonstrating that the symptoms were really due to the induced deficiency. Although the mineral contents of leaves with deficiency symptoms were always lower than those found in other samplings, the reference leaf, recommended in the literature for cocoa (3rd leaf starting from tip), was also adequate for cupuaçu, except in the case of Cu.

Com a finalidade de induzir os sintomas visuais de deficiência nutricional no cupuaçuzeiro, realizou-se em casa de vegetação, um experimento com solução nutritiva onde omitiu-se os seguintes elementos: N, P, K, Ca, Mg, S, B, Cu, Fe, Mu e Zn. Um tratamento completo serviu de comparação. Todos os sintomas foram caracterizados e apresentaram semelhanças com os observados para o cacaueiro, sendo relacionados em tabela para a identificação. Para determinar as concentrações de nutrientes, foram coletadas folhas em diversas partes da planta e em duas épocas de amostragem. Os teores encontrados nas folhas em que o elemento foi omitido foram sempre inferiores daqueles encontrados no tratamento completo, demonstrando que os sintomas descritos foram realmente devidos ao efeito da omissão. Embora os teores apresentados nas folhas com sintomas de deficiência tenham sido sempre menores que os obtidos nas demais amostragens, a folha de referência indicada pela literatura para o cacaueiro (3ª a partir do ápice), mostrou-se adequada para identificar deficiências nutricionais no cupuaçuzeiro, exceto para o cobre.

Efeito da adição de diferentes fontes de cálcio no movimento de cátions em colunas de solo

Soil columns under controlled conditions were used to determine the movement of calcium and other cations after the application of lime, calcium oxide, gypsum and a mixture of Ume and gypsum, compared with a control treatment. Two Oxisols with different textures were used: clayey and silty. Rigid polyvinyl chloride (PVC) columns (length, 45cm; diam, 5cm) were used, applying 1.8 1 of water to each divided into four applications. Exchangeable cations were determined in the drainage water in 4 periods and in 5 dephts of the soil columns at the end of the experiment. The results showed that losses of Ca2+, Mg2+, K+ and A1(3+), were higher in the treatments with gypsum and lime plus gypsum. Amendments h'ke lime and calcium oxide did not promote significant losses of cations. Large losses occured in the silty and clayey soils in the first and second drainage times respectively. Gypsum did not modify the pH of both soils, but reduced cation amounts mainly in the clayey soil. Lime and calcium oxide raised the pH only near the application layer.

No estudo realizado em colunas de solo montadas em laboratório, procurou-se avaliar o movimento do cálcio, e de outros cátions, após aplicação de calcário agrícola, gesso, calcário calcinado e uma mistura de calcário agrícola e gesso, comparados com um tratamento testemunha, em dois latossolos vermelho escuros de texturas diferentes: média e argilosa. Utilizaram-se colunas de PVC, com 5cm de diâmetro e 45cm de altura, e aplicaram-se em cada coluna 1,8 litros de água, parcelados em quatro vezes. Determinaram-se os cátions trocáveis presentes na água percolada e, no final do experimento, em cinco profundidades de cada solo. Os resultados mostraram que nos tratamentos gesso e calcário mais gesso as quantidades de Ca2+, Mg2+, K+ e Al3+ na solução percolada foram maiores, enquanto que os tratamentos calcário agrícola e calcário calcinado não promoveram perdas significativas de cátions. As maiores perdas ocorreram na primeira percolação no solo de textura média e na segunda no solo de textura argilosa. O gesso não modificou o pH dos solos, mas reduziu teores de bases no solo argiloso, enquanto que os calcários corrigiram o solo apenas próximo à camada de incorporação.

Efeito da adição de diferentes fontes de cálcio no movimento de cátions em colunas de solo

Soil columns under controlled conditions were used to determine the movement of calcium and other cations after the application of lime, calcium oxide, gypsum and a mixture of Ume and gypsum, compared with a control treatment. Two Oxisols with different textures were used: clayey and silty. Rigid polyvinyl chloride (PVC) columns (length, 45cm; diam, 5cm) were used, applying 1.8 1 of water to each divided into four applications. Exchangeable cations were determined in the drainage water in 4 periods and in 5 dephts of the soil columns at the end of the experiment. The results showed that losses of Ca2+, Mg2+, K+ and A1(3+), were higher in the treatments with gypsum and lime plus gypsum. Amendments h'ke lime and calcium oxide did not promote significant losses of cations. Large losses occured in the silty and clayey soils in the first and second drainage times respectively. Gypsum did not modify the pH of both soils, but reduced cation amounts mainly in the clayey soil. Lime and calcium oxide raised the pH only near the application layer.

No estudo realizado em colunas de solo montadas em laboratório, procurou-se avaliar o movimento do cálcio, e de outros cátions, após aplicação de calcário agrícola, gesso, calcário calcinado e uma mistura de calcário agrícola e gesso, comparados com um tratamento testemunha, em dois latossolos vermelho escuros de texturas diferentes: média e argilosa. Utilizaram-se colunas de PVC, com 5cm de diâmetro e 45cm de altura, e aplicaram-se em cada coluna 1,8 litros de água, parcelados em quatro vezes. Determinaram-se os cátions trocáveis presentes na água percolada e, no final do experimento, em cinco profundidades de cada solo. Os resultados mostraram que nos tratamentos gesso e calcário mais gesso as quantidades de Ca2+, Mg2+, K+ e Al3+ na solução percolada foram maiores, enquanto que os tratamentos calcário agrícola e calcário calcinado não promoveram perdas significativas de cátions. As maiores perdas ocorreram na primeira percolação no solo de textura média e na segunda no solo de textura argilosa. O gesso não modificou o pH dos solos, mas reduziu teores de bases no solo argiloso, enquanto que os calcários corrigiram o solo apenas próximo à camada de incorporação.