ABSTRACT Degradation of bovine small intestine and respective effects on biomechanics have not been described to date. Biomechanical testing of intestinal tissues is often carried out within a few hours of donor death and tissue deterioration is not accounted for. Freezing is efficient for the preservation of several tissues; however, it may cause cellular damage. This study investigated the morphologic and biomechanical changes of bovine jejunum at different postmortem moments. Effects of freezing and thawing on morphology and biomechanical behavior were also examined. Macroscopic changes were first noted within eight hours of death. At this time, histologic changes also started to set in, and biomechanical tests revealed lower bursting pressure (203.10±46.14mmHg). At 12 hours, tissue rearrangement was noted, and bursting pressure increased (238.43±31.04mmHg). A second drop in pressure was detected at 18 hours (235.20±38.21mmHg), followed by a progressive drop until the end of the experimental period. Histologic changes revealed progressive deterioration. Mechanical resistance did not differ between thawed and fresh specimens. It was concluded that bovine jejunal specimens retain biomechanical resistance up to 6 hours after death. Freezing and thawing did not affect the mechanical resistance of the intestinal wall in this experimental model. date however damage moments examined time 203.10±46.14mmHg. 203104614mmHg mmHg 203.10±46.14mmHg . 203 10 46 14mmHg (203.10±46.14mmHg) 1 238.43±31.04mmHg. 238433104mmHg 238.43±31.04mmHg 238 43 31 04mmHg (238.43±31.04mmHg) 235.20±38.21mmHg, 235203821mmHg 235.20±38.21mmHg , 235 20 38 21mmHg (235.20±38.21mmHg) period model 4 (203.10±46.14mmHg 23 3 (238.43±31.04mmHg 2 (235.20±38.21mmHg

RESUMO A degradação do intestino delgado de bovinos e seu efeito biomecânico não são descritos na literatura. Trabalhos que envolvem a biomecânica intestinal realizam os ensaios em poucas horas após o óbito dos doadores, sem avaliação de seu estado de deterioração. O congelamento é eficiente na conservação de vários tecidos, porém pode provocar danos em nível celular. Este estudo teve por objetivo avaliar a degradação morfológica e biomecânica do jejuno de bovinos em diferentes tempos post mortem. O efeito do congelamento e do descongelamento sobre essas características também foi avaliado. As primeiras alterações macroscópicas foram observadas oito horas após o óbito. No mesmo momento, se iniciaram as alterações histológicas e a menor pressão suportada ao teste biomecânico (203,10±46,14mmHg). A partir de 12 horas, o tecido sofreu um rearranjo, suportando maior pressão (238,43±31,04mmHg). Uma segunda queda foi detectada após 18 horas (235,20±38,21mmHg), seguida de redução progressiva até o término do experimento. As lesões histológicas foram progressivas e graduais. As amostras testadas após descongelamento não apresentaram diferença estatística quanto à resistência mecânica em comparação com os espécimes frescos. Concluiu-se que as amostras mantêm sua resistência biomecânica até 6 horas após o óbito. Também se mostrou que o congelamento e o descongelamento, nas condições testadas, não alteraram a resistência mecânica da parede intestinal. literatura doadores deterioração tecidos celular mortem avaliado momento 203,10±46,14mmHg. 203104614mmHg mmHg 203,10±46,14mmHg . 203 10 46 14mmHg (203,10±46,14mmHg) 1 rearranjo 238,43±31,04mmHg. 238433104mmHg 238,43±31,04mmHg 238 43 31 04mmHg (238,43±31,04mmHg) 235,20±38,21mmHg, 235203821mmHg 235,20±38,21mmHg , 235 20 38 21mmHg (235,20±38,21mmHg) experimento graduais frescos Concluiuse Concluiu 4 (203,10±46,14mmHg 23 3 (238,43±31,04mmHg 2 (235,20±38,21mmHg

The aim of this study was to assess the digestibility coefficients (DC) of corn [maize] with an oil content above 3.46% and its effects on the performance of piglets when fed as dry grain (DG) and as rehydrated corn grain silage (RCGS). In Experiment I, 15 piglets (22.51 + 2.39 kg) were allocated to a reference diet (RD) and to two test diets in which corn in the RD was replaced with DG or RCGS. There were five replications of each treatment. Experiment II involved 36 piglets (14.76 ± 2.72 kg), which were assigned to a control diet with common corn grain and to diets in which DG or RCGS replaced the common corn. There were six replications of each treatment. Data were analysed with four statistical models. Model 1 included only the effect of treatment. Model 2 was similar to Model 1 but included initial bodyweight as a covariate. Model 3 was similar to model 1 but included the interaction of diet and period. Model 4 was similar to Model 3 but included the covariate. The more complicated models were generally preferred to Model 1 as they controlled more of the nuisance variation. Feeding a diet that contained RCGS reduced feed intake and improved feed conversion ratio (FCR).

RESUMO O objetivo foi avaliar os efeitos de uma subdose de hCG aplicada no acuponto Hou Hai na qualidade do corpo lúteo (CL) e na indução da ovulação em éguas. Quinze éguas mestiças foram distribuídas em blocos ao acaso, sendo o período utilizado como fator de blocagem, em: T1 = 1500 UI de hCG por via intravenosa (IV); T2 = 450 UI de hCG aplicado no falso acuponto (IV) e T3 = 450 UI de hCG aplicada no acuponto Hou Hai. Avaliou-se diâmetro médio do CL, concentração sérica de progesterona (P4), vascularização do folículo pré-ovulatório e do CL. As fêmeas que receberam 450 UI de hCG no acuponto Hou Hai apresentaram maiores taxas de ovulação (33,33%) 48h após a indução. O número de pixels coloridos (NPC) mínimo do folículo pré-ovulatório das fêmeas do grupo controle foi superior (40,33) ao das éguas que receberam 450 UI de hCG IV no falso acuponto (36,84) e semelhante ao das éguas que receberam hCG no acuponto Hou Hai (39,31); correlações moderadamente positivas foram encontradas entre o diâmetro do CL e a concentração de P4, ambos no D8 (P <0,05). A administração IV de 450 UI de hCG ou no acuponto Hou Hai foi eficiente na indução da ovulação e na garantia da qualidade do CL nas éguas.

ABSTRACT The objective of this study was to evaluate the effects of an hCG sub dose applied at the Hou Hai acupoint on corpus luteum (CL) quality and ovulation induction in mares. Fifteen crossbred mares were distributed in randomized blocks and used in three periods with each period employed as the blocking factor in three treatments: T1 = 1500 IU of hCG via intravenous (IV); T2 = 450 IU of hCG applied at the false acupoint (IV); and T3 = 450 IU of hCG applied at the Hou Hai acupoint. Mean diameter of the CL, serum concentration of progesterone (P4), vascularization of the pre-ovulatory follicle and CL were evaluated. Females administered 450 IU of hCG at the Hou Hai acupoint exhibited greater ovulation rates (33.33%) 48h after induction; The minimum number of colored pixel (NCP) of the pre-ovulatory follicle of control females was superior (40.33) to that of mares administered 450 IU of hCG IV at the false acupoint (36.84) and similar to that of those administered hCG at the Hou Hai acupoint (39.31). Further, moderately positive correlations were found between the CL diameter and the P4 concentration on D8 (P<0.05). IV administration of 450 IU of hCG or at the Hou Hai acupoint was efficient at inducing ovulation and ensuring the quality of CL in mares.

RESUMO A síndrome de granuloma leproide canino (SGLC), também conhecida como lepra canina, é uma doença infecciosa cutânea nodular causada por Mycobacterium sp. Apesar de ser relatada mundialmente, ainda é bastante desconhecida e subdiagnosticada. O diagnóstico pode ser conseguido por citopatologia ou histopatologia de lesões cutâneas, mas a identificação do agente infeccioso é complexa, uma vez que o crescimento in vitro bacteriano não é possível, dependendo de técnicas moleculares como a PCR para confirmar o DNA de Mycobacterium na amostra. Relatou-se um caso da SGLC em Niterói, estado do Rio de Janeiro, Brasil, diagnosticado por citopatologia e submetido à identificação molecular do agente. Foi realizada amplificação por PCR do gene hsp65, que revelou 100% de homologia genética com a cepa M. murphy. Este é o primeiro relato da SGLC com identificação molecular no estado do Rio de Janeiro, o que mostra a importância de se acrescentar a SGLC ao diagnóstico diferencial das doenças granulomatosas de pele nessa região.

ABSTRACT Canine Leproid Granuloma Syndrome (CLGS), also known as canine leprosy, is a cutaneous nodular infectious disease caused by Mycobacterium sp.. Despite being reported worldwide, it is still quite unknown and underdiagnosed. Diagnosis may be achieved by cytopathology or histopathology of skin lesions, but identification of the infectious agent is complex, since bacterial in vitro growth is not possible, relying upon molecular techniques such as PCR to confirm Mycobacterium DNA in the sample. We report a CLGS case in Niteroi, Rio de Janeiro state, Brazil, diagnosed by cytopathology and submitted to molecular identification of the agent. PCR amplification of hsp65 gene was performed and revealed 100% genetic homology to M. murphy strain. This is the first CLGS report with molecular identification in Rio de Janeiro state, and this finding should raise awareness about CLGS as a differential diagnosis among granulomatous skin diseases in this region.

RESUMO As neoplasias ovarianas em gatas são raras e, quando relatadas, estão associadas a animais senis, assim como a piometra de causa não iatrogênica. O objetivo deste trabalho foi relatar o caso de uma gata jovem com neoplasia ovariana, tumor de células da granulosa associado ao complexo hiperplasia endometrial cística/piometra (HECP). O animal foi atendido no setor de Reprodução Animal e Obstetrícia Veterinária (RAOV) de um Hospital Veterinário Escola, com histórico de monta natural recente, anorexia, êmese, polidipsia, poliúria e descarga vaginal purulenta. Ao exame físico, observou-se apatia, mucosas ictéricas, aumento de volume da região abdominal e presença de secreção vaginal purulenta. À ultrassonografia, foi visibilizado conteúdo ecogênico no útero diagnóstico de HECP e estrutura ecogênica na cavidade abdominal, na região ovariana, confirmado pelo exame histopatológico como sendo tumor das células da granulosa. A conduta terapêutica adotada foi a cirurgia de ovariossalpingo-histerectomia (OSH).

ABSTRACT Ovarian neoplasias in cats are rare, and are associated with advanced ages, as well as non-iatrogenic pyometra. The objective of the present study was to report a case of a young cat showing signs of a rare neoplasia, the granulosa-cell tumor, associated with complex cystic endometrial hyperplasia/pyometra (HECP). The animal was attended in the Animal Reproduction and Veterinary Obstetrics sector of a Teaching Veterinary Hospital with a history of natural breeding, anorexia, emesis, polydipsia, polyuria, and purulent vaginal discharge. During clinical examination, apathy, icterus, swelling of the abdomen, and purulent vaginal discharge were observed. On the ultrasonographic exam, an echogenic content inside the uterus was observed, leading to diagnosis of HECP and an echogenic structure in the abdominal cavity, in ovarian region, confirmed by histopathology as being of granulosa cells. The therapeutic conduct adopted was salpingo-oophorectomy and hysterectomy surgery (OSH).

Este trabalho teve por objetivo avaliar a seletividade do oxyfluorfen e do sulfentrazone e o controle de plantas daninhas em diferentes épocas após o transplantio das mudas de café no campo. Foram realizados três ensaios no delineamento experimental de blocos casualizados com dez tratamentos e quatro repetições. No ensaio 1, aos 30 dias após o transplantio (DAT) e, no ensaio 2, aos 90 DAT, testaram-se duas doses de oxyfluorfen (0,36 e 0,72 kg i.a. ha-1) e de sulfentrazone (0,4 e 0,6 kg i.a. ha-1), em jato dirigido ao solo (com proteção das mudas) e em área total. No ensaio 3, os mesmos herbicidas e doses foram aplicados, porém aos 300 DAT e apenas em aplicação dirigida, testando-se duas pontas de pulverização de diferentes potenciais de deriva. Em todos os ensaios, acrescentaram-se as testemunhas capinada e sem capina. A entrelinha foi manejada com roçada. Foram identificadas as espécies de plantas daninhas e suas densidades. A eficácia dos herbicidas e suas seletividades também foram avaliadas. A principal planta daninha que ocorreu na área experimental foi Brachiaria decumbens. Sintomas visuais de toxicidade foram observados apenas quando os herbicidas foram aplicados em área total (ensaios 1 e 2), independentemente da dose e época de aplicação. No ensaio 3, independentemente do herbicida, da dose e da ponta utilizada, não houve sintomas visuais de toxicidade, nem redução no crescimento das plantas, em função da aplicação dirigida. Em todas as épocas o controle de plantas daninhas foi eficiente, porém a seletividade só foi alcançada na aplicação dirigida, para ambos os herbicidas.

This study aimed to evaluate oxyfluorfen and sulfentrazone selectivity and weed control in young coffee plantations (Coffea arabica cv. Red Catuaí). Three trials were conducted in a randomized complete block design, with 10 treatments and four replicates. In the first and second trials, at 30 and 90 days after transplanting (DAT), respectively, two doses of oxyfluorfen (0.36 and 0.72 kg a.i. ha-1) and sulfentrazone (0.4 and 0.6 kg a.i. ha-1) were tested by spraying the herbicides directly into soil (with seedling protection) or onto the total area. The same herbicides and doses were used in the third trial, but at 300 DAT and only directed to the soil, using two sprayer nozzles with different drift potentials being tested. Two additional control plots were added: hand-weeding control and weedy treatments. Weeds present in the inter-row spaces were eliminated by mowing operations. Weeds and their densities were identified. The toxicity of the herbicides to the coffee plants and its effectiveness in controlling the weeds were assessed. The main weed occurring in the experimental area was Brachiaria decumbens. Visual symptoms of herbicide toxicity were observed only when the herbicides were applied in the entire area (trials 1 and 2), regardless of their doses and application times. At the third herbicide application trial, no visual symptoms of herbicide toxicity and no reductions in plant growth were observed, regardless of the herbicide, the dose and the sprayer nozzles tested. At all times, a very good weed control percentage was obtained, but selectivity occurred only when the herbicides were not applied onto the total area.

O objetivo deste estudo consistiu em determinar a faixa ideal de controle de plantas daninhas (FCPD) necessária para um crescimento adequado do cafeeiro após o transplantio. Foi utilizada uma lavoura não irrigada, implantada no espaçamento de 3,80 x 0,70 m, em dezembro de 2008. O delineamento experimental foi em blocos casualizados, com quatro repetições. Os tratamentos foram dispostos em um esquema de parcelas subdivididas (9 x 18) para testar as FCPDs de 0, 15, 30, 45, 60, 90, 120, 150 e 190 cm, mantidas com capina contínua em cada lado da linha de café, bem como seus efeitos ao longo de 18 meses após o transplantio (MAT). Efetuaram-se análises de regressão múltipla que relacionaram as variáveis de crescimento em função da FCPD e das épocas de avaliação do crescimento. A principal espécie identificada foi a poácea Brachiaria decumbens, com 88,5% da matéria seca total das plantas daninhas. A largura mínima da FCPD aumentou com a idade da cultura após o transplantio. Assumindo reduções de 2 e 5% no crescimento máximo do cafeeiro, as FCPDs recomendadas foram de 75 e 52 cm aos 4 MAT, 104 e 85 cm aos 6 MAT, 123 e 105 cm aos 9 MAT, 134 e 116 cm aos 12 MAT, 142 e 124 cm aos 15 MAT e 148 e 131 cm aos 18 meses após o transplantio, respectivamente. Conclui-se que o manejo das plantas daninhas em lavouras jovens de café deve buscar a manutenção apenas de uma faixa de controle mínima na linha de plantio, cuja largura aumenta com a idade da lavoura, preservando a vegetação na entrelinha.

The aim of this study was to determine the weed strip control (WSC) required for adequate coffee growth after transplanting. A non-irrigated, field-planted (spaced 3.80 x 0.70 m) crop was used. The experimental design was a randomized block, with four replicates. The treatments were arranged in a 9 x 18 split-plot design to test the WSC of 0, 15, 30, 45, 60, 90, 120, 150, and 190 cm, which involved continuously hand-weeding at each side of the coffee row, and 18 coffee growth measurements. Multiple regression analyses were carried out relating to growth-variables as a function of both WSC and growth-evaluation times. Brachiaria decumbens was the main weed accomplishing 88.5% of the total weed dry mass. The minimum width of the WSC increases as the crop ages after transplanting. Assuming reductions of 2% and 5% in the maximum coffee growth, the recommended WSC was 75 and 52 cm at 4 months after transplanting (MAT), 104 and 85 cm at 6 MAT, 123 and 105 cm at 9 MAT, 134 and 116 cm at 12 MAT, 142 and 124 cm at 15 MAT, and 148 and 131 cm at 18 MAT, respectively. It was concluded that integrated weed management in young coffee crops must focus on the weed control only in a minimum range along coffee rows, which increases with coffee plant age, keeping natural vegetation in the inter-rows.

Foram realizados dois experimentos com o objetivo de estudar, no primeiro, o efeito de diferentes relações treonina:lisina digestíveis (TL) sobre a utilização do nitrogênio (N) em suínos na fase inicial, dos 15 aos 30kg de peso, e, no segundo, o efeito dessas relações sobre o desempenho dos animais. No primeiro experimento, foi avaliado o balanço de nitrogênio, utilizando-se 20 suínos machos castrados, híbridos comerciais de média a alta deposição de tecido magro, com peso inicial de 23,0±4,1kg. Os suínos foram distribuídos em um delineamento experimental inteiramente ao acaso. As rações continham baixo nível de proteína (17,3%), e as relações TL foram: 0,574; 0,624; 0,673; 0,722 e 0,772. A proteína bruta total excretada (PBTE), a proteína bruta retida (PBR) e a utilização líquida da proteína (ULP) apresentaram efeito quadrático, e os melhores valores nas relações foram 0,648; 0,648 e 0,649, respectivamente. A melhor relação TL foi 0,649 (média da PBR e ULP). No segundo experimento, foi avaliado o efeito dessa relação sobre o desempenho dos suínos na fase inicial. Foram utilizados 60 animais (30 machos castrados e 30 fêmeas) com peso inicial de 15,5±1,5kg, de características semelhantes ao primeiro experimento, distribuídos em um delineamento experimental inteiramente ao acaso, em esquema fatorial 5x2 (cinco relações TL e dois sexos, com dois animais por baia). Foram utilizadas seis baias por tratamento, com três de machos e três de fêmeas cada. Não houve efeito da relação TL sobre o consumo diário de ração e o ganho diário de peso, e houve efeito quadrático, com ponto de mínimo, sobre a conversão alimentar com a relação TL de 0,691. Os resultados indicam que a relação TL de 0,649 maximiza a retenção de nitrogênio e a relação TL de 0,691 permite melhor conversão alimentar para leitões dos 15 aos 30kg de peso.

Two experiments were carried out to evaluate the effect of digestible threonine:lysine ratio (TL) on nitrogen (N) use and on growth performance of starting pigs (15-30kg). Experiment I evaluated nitrogen balance using twenty high-lean commercial crossbred barrows, with initial weight of 23.0±4.1kg. Pigs were allotted in a randomized design. Diets were formulated with low crude protein levels (17.3 %) and TL ratios were: 0.574; 0.624; 0.673; 0.722; and 0.772. Excreted crude protein (CPEX), crude protein retention (CPR), and net protein utilization (NPU) showed quadratic effect and the best TL ratio values were achieved at 0.648, 0.648, and 0.649, respectively. The best TL ratio was 0.649 (CPR and NPU means). Experiment II was carried out to examine the same TL ratio effects on the performance of pigs. Sixty pigs (30 barrows and 30 gilts), averaging 15.5±1.5kg, used in experiment II, were allotted in a randomized design, following a factorial scheme (5x2), being five TL ratios (same as in experiment I) and two genders. Six pens per treatment (three barrows and three gilts) were used. There was no effect of TL ratio on daily feed intake and on average weight gain. However, the feed:gain ratio showed a quadratic effect and the best TL ratio was achieved at 0.691. The results pointed out that the 0.649 TL ratio maximized nitrogen retention and the 0.694 TL ratio allowed a better feed conversion for starting pigs averaging 15 to 30kg of b.w.

The antimicrobial resistance of 96 Escherichia coli strains isolated from a stabilization pond system on a pig-breeding farm was evaluated. Strains were tested for their resistance against 14 antimicrobial using the agar diffusion method. E. coli strains showed resistance to tetracycline (82.3%), nalidixic acid (64%), ampicilin (41%), sulfamethoxazole/trimethoprin (36%), sulfonamide (34%), cloranphenicol (274%), ciprofloxacin (19%), cefaclor (16%), streptomicyn (7.3%), neomicyn (1%), amoxacilin/ clavulanic acid (1%), and amikacin (1%). No resistance was observed to gentamicin and tobramycin, and 37.5% of E. coli strains were resistant to four or more antimicrobials. The multiresistance pattern was found in strains isolated during all sampled period. Strains showed a high variability in the antimicrobial resistance pattern.

The odoriferous species Lippia sidoides Cham. is abundant in the Brazilian Northeast. Its essential oil possesses antiseptic activity due to the presence of thymol. In this work, thermodynamic and kinetic data were experimentally determined for the CO2 + L. sidoides system. Solubility was determined using the dynamic method at pressures of 66.7 and 78.5 bar and temperatures of 283.15, 288.15, 293.15, 295.15, and 298.15 K. SFE kinetic data were obtained at 288.15 K and 66.7 bar. The composition of the multicomponent solute mixture was determined by GC-MS and compared to the composition of both the volatile oil obtained by steam distillation and the oleoresin obtained using ethanol. The SFE process yield was higher than the yield of either the steam distillation or the ethanol extraction. The solubilities were correlated using the Peng-Robinson equation of state with one binary interaction parameter for the attractive term, considering the essential oil as a pseudo-component. Sovová’s model quantitatively described the overall extraction curve.

The objective of this work was to study the recovery of aroma compounds present in the orange essential oil using experimental data from CUTRALE (a Brazilian Industry of Concentrated Orange Juice). The intention was to reproduce the industrial unit and afterwards to optimize the recovery of aroma compounds from orange essential oil by liquid-liquid extraction. The orange oil deterpenation was simulated using the commercial software PRO/II 4.0 version 1.0. The UNIFAC model was chosen for the calculation of the activity coefficients.

One of the most important byproducts of the orange juice industry is the oil phase. This is a mixture of terpenes, alcohols, and aldehydes, dissolved in approximately 96% limonene. To satisfactorily use oil phase as an ingredient in the food and cosmetics industries separation of the limonene is required. One possibility is to use a fixed bed of silica gel to remove the light or aroma compounds from the limonene. The aroma substances are then extracted from the bed of silica gel using supercritical carbon dioxide. This work deals with the modeling of the desorption step of the process using mass balance equations coupled with the Langmuir equilibrium isotherm. Data taken from the literature for the overall extraction curves were used together with empirical correlations to calculate the concentration profile of solute in the supercritical phase at the bed outlet. The system of equations was solved by the finite volume technique. The overall extraction curves calculated were in good agreement with the experimental ones.

O presente trabalho foi desenvolvido na Estação Experimental de Piracicaba, SP, utilizando-se seis cultivares de cana-de-açúcar, com o objetivo de comparar a porcentagem de colmos infestados e a intensidade de infestação como técnicas para avaliar o ataque pelo complexo broca-podridões. As cultivares foram plantadas em abril de 1985, sendo as avaliações realizadas nos meses de maio, julho e setembro do ano seguinte. Com base nos resultados obtidos, constatou-se que não há diferenças entre as porcentagens de colmos infestados externa e internamente pelo complexo broca-podridões. A intensidade de infestação interna foi maior que a externa, verificando-se entre estes parâmetros uma correlação linear positiva e altamente significativa. Nem sempre se constatou correlação significativa entre porcentagem de colmos infestados e intensidade de infestação. A maior porcentagem de internódios infestados foi observada na região basal do colmo, e a menor na apical.

This research was conducted at the Experimental Station of Piracicaba, São Paulo, Brazil. Six sugarcane cultivars were studied with the main purpose of comparing the percentage of infested stalks and the intensity of infestation by the borer - rot complex. The cultivars were planted in April of 1985 and the evaluations were made in May, July and September of 1986. The results indicated that there were no differences between the internal and external percentages of infested stalks. The internal and external intensities of infestation presented a positive and highly significant linear correlation. On the other hand, a significant correlation between the percentage of infested stalks and the intensity of infestation was not always found. The highest percentage of infested internodes was observed at the basal region of the stalk and the lowest at the apical one.

Azolla filiculoides Lam foi cultivado em solução nutritiva arejada, sempre desprovida de N combinado, sendo submetida aos seguintes tratamentos: omissão de P, K, Ca, Mg, S, Fe e Mo, excesso de Mn e Al. As plantas foram colhidas depois de 3 semanas da inoculação. Verificou-se que as deficiências de P, K, Ca e Mg provocaram diminuição na produção de matéria seca e na atividade de nitrogenase. A análise mineral mostrou que: a falta de um elemento provoca redução no seu teor; grande acumulo de Mo; diminuição no teor de Al (do inóculo ou contaminação) no tratamento menos S que garantiu o maior crescimento; efeitos inibitórios ou sinergísticos semelhantes aos descritos no caso de plantas superiores. A toxidez de Al e Mn causou, principalmente a primeira, redução no crescimento e na atividade da nitrogenase. Houve correlações positivas entre: N total e crescimento, atividade de nitrogenase e N total.

The mineral nutrition of Azolla feliculoides Lam was studied in solutions deficient in phosphorus, potassium, calcium, magnesium, sulfur, iron and molybdenum, and in excess of Mn and Al. Dry weight, N2 fixation and mineral composition of Azolla were determined after 3 weeks. Phosphorus, potassium, calcium and magnesium deficiencies and excess of manganese and aluminium decressed growth severely and also depressed the activity of nitrogenase. Phosphorus deficiency improved the uptake of iron and zinc. Potassium deficiency increased the levels of phosphorus in dry matter. Magnesium deficiency caused lower uptake of K and better uptake of Ca, Fe and Mn. Sulfur deficiency reduced aluminium uptake and promoted the best growth. Positive correlations were found between: N content and dry matter, nitrogenase activity and N content.