MSCAGR (Animal Science) / One of the ways to minimise cost and promote health in humans and animals is to use natural feed additives instead of antibiotics. Moringa oleifera (Moringa) is a phytobiotic which possess anti-microbial and immune-modulatory properties and contains high levels of nutrients and it can be used as a feed additive. Probiotics are feed additives which consist of living microorganisms that have beneficial effects on the physiology and health of other organisms. The objective of the study was to determine the effect of various levels of Moringa oleifera and probiotics inclusion on growth performance, carcass characteristics and cost benefit analysis for broiler chicken production. Moringa oleifera leaf powder was purchased from Bethel Farm No:683 Bethel mission Gucksdadt Vryheid in Zululand district AbaQulusi municipality. The study was a 5x2 factorial design with five levels of Moringa and two levels of probiotic. Six hundred (600) Ross 308-day old chicks were received and fed commercial starter. The experimental treatments were randomly divided into five levels of Moringa with and without probiotics introduced through drinking water at grower to finisher phase. The diets were supplemented with different inclusion levels of Moringa (Mo) as follows: 0g/kg (M0), 0.6g/kg (M3), 1.2g/kg (M6), 1.8g/kg (M9), 2.4g/kg (M12) of Moringa oleifera leaf meal (MOLM) and probiotic at P0 (0ml/bird/week), P1 (1 ml/bird/week) of a commercial probiotic administered in water for the first three weeks (starter phase). The experiment had three replications with 20 birds per replicate. MOLM and PRB interaction had no significant effect (P>0.05) on any of growth parameters and same findings with MOLM. Probiotics treatments had significantly reduced (P < 0.05) mortality rate (MTRT) in the grower phase. MOLM×PRB had significant effect on (P<0.01) feed intake (FI), MOLM had significantly reduced (P< 0.05) average bodyweight gain (ABWG) and FI in finisher phase. MOLM and PRB interaction had significant effect (P< 0.05) on dressed weight only and non-significant effect (P>0.05) on the rest of carcass parameters. MOLM inclusion levels did not significantly affect (P>0.05) back fat weight. However, MOLM inclusion level significantly reduced (P< 0.05) dressed weight, shank length, wing weight, drum and thigh weight, back weight and breast muscle weight. PRB inclusion in the diets significantly increased (P< 0.01) shank size and drum + thigh weights (P<0.05). MOLM and PRB inclusion level had no significant effect (P>0.05) on giblets parameters. MOLM and PRB interaction had significant effect on (P<0.05) water holding capacity (WHC) and hardness. MOLM had significant effect (P<0.05) on pH and dripping loss. A significant effect between (MOLM×PRB) Moringa oleifera leaf meal and probiotics (P<0.01) was observed on CD, C* and b*. MOLM had significant effect (P<0.01) on CD, C*, a*, b*, L*, PRB had significant effect (P<0.01) on h*(increased) and a*(reduced) on colour parameters. MOLM fed at P0 resulted in higher mortality at grower stage. It is concluded that MOLM can be added up to 12% with or without PRB without affecting growth performance at finisher phase and carcass characteristics. Inclusion of MOLM up to 12% had good impact on hardness and water holding capacity in the meat. PRB presence improved the growth performance of birds supplemented with MOLM up to 12% inclusion level. MOLM diets were not economically profitable compared to control diet due to high price level of Moringa oleifera powder supplemented in the diets and no best return weight gain per rand invested amongst the diets. / NRF

Maize is the third most important cereal crop in the world and many subsistence farmers are practicing intercropping of it with legumes due to land scarcity and in order to enhance production. Intercropping system is being practiced in may areas of South Africa mainly in the Limpopo province. The objective of the study was to evaluate the crop responses to intercropping maize with different growth length cowpea cultivars. The effects of intercropping on weed growth, maize and cowpea growth and yield components were investigated. The experiment was conducted during the 2005/06 and 2006/07 seasons at Bethlehem and Potchefstroom. Treatments were: maize sole, maize+PAN311 (short duration cowpea cultivar), maize+Glenda (medium duration cowpea cultivar), maize+Agrinawa (long duration cowpea cultivar) and sole plots of all cowpea varieties. Each plot was divided into two weed levels where all the plots were kept weed free for one month after planting, after which one half was left weedy and the other half weed free. Weed sampling was done within each weed treatment. Intercropping reduced maize LAI and plant height while time to physiological maturity was also reduced by weed infestation, especially under drier and warmer environments. Glenda and Agrinawa intercrops produced more nodules per plant under cooler and wetter conditions. Agrinawa produced the highest leaf and total DMY under sole crop conditions and this was significantly reduced by weed infestation. Different growth duration cultivars did not differ in their N2-binding abilities. Maize intercropping, especially with Glenda and Agrinawa, significantly reduced weed biomass. Maize sole crop under zero weeds had high grain yield compared to intercropping. PAN311 and Glenda sole crops under zero weeds produced higher yields under dry and warmer conditions, and cooler and wetter conditions, respectively, compared to intercropping. High cowpea grain yields were strongly correlated to more seeds per pod and larger pod lengths and number of pods per plant especially for Glenda. No intercropping advantage compared to sole cropping was observed (total LER < 1). This implies that maize and cowpeas must rather be planted as sole crops for better yields under wetter and cooler, and warmer and drier conditions. Copyright / Dissertation (MSc(Agric))--University of Pretoria, 2009. / Plant Production and Soil Science / unrestricted

2012 metų rugsėjo – spalio mėn. Lietuvos agrarinių ir miškų mokslų centro Sodininkystės ir daržininkystės instituto Augalų fiziologijos laboratorijos fitotroninio komplekso uždaro reguliuojamo klimato kamerose tirta UV-A (+366, +390, +402 nm) spinduliuotės įtaka mikrožalumynų vidiniams ir išoriniams kokybės rodikliams. Darbo objektas – po skirtingais UV-A šviesos diodais, papildančiais bazinį (447 nm, 638 nm, 665 nm ir 731 nm) apšvietimą auginti kiniško kopūsto ‘Rubi’ (Brassica rapa var. chinensis, ‘Rubi’), kvapiojo baziliko ‚Sweet Genovese‘ (Ocimum basilicum L., ‚Sweet Genovese‘) ir burokėlio (Beta vulgaris L., ‘Bulls Blood’) mikrožalumynai. Darbo metodai: Augalo hipokotilio bei antžeminės dalies aukštis (cm) matuotas slankmačiu. Žalios masės kiekis (mg) nustatyta antžeminę augalo dalį pasvėriant svarstyklėmis. Lapų plotas matuotas lapų ploto matuokliu. Sacharidų (rafinozės, sacharozės, gliukozės, manozės, fruktozės) kiekis nustatytas skysčių chromatografijos metodu. Nitratų kiekis nustatytas potenciometriniu metodu. Fotosintezės pigmenų (chlorofilo a ir chlorofilo b) kiekis nustatytas spektrofotometriniu metodu pagal Wetshtein. Darbo rezultatai: Ištyrus papildomų UV-A šviesos diodų spinduliuotės poveikį mikrožalumynų biometriniams rodikliams, nustatyta, kad jis priklausė nuo augalo rūšies. Tiriant skirtingų bangos ilgių šviesos diodų derinių poveikį augalams nustatyta, kad didesnę teigiamą įtaką kiniško kopūsto mikrožalumynų lapų plotui ir žaliai masei turėjo papildomi 366... [toliau žr. visą tekstą] / In September – October, 2012, the investigation was performed in the Research Centre of Agriculture and Forestry, the Institute of Horticulture and Gardening of Lithuania, in the laboratory of plant physiology phytothron complex of closed adjustable climate chambers. It was evaluated the influence of the UV-A irradiation on the internal and external quality of microgreens Object of the research: The microgreens of the chinese cabbage ‘Rubi’ (Brassica rapa var. chinensis, ‘Rubi’), sweet basil ‘Sweet Genovese’ (Ocimum basilicum L., ‘Sweet Genovese’) and beet ‘Bulls Blood’ (Beta vulgaris L., ‘Bulls Blood’) were grown under different UV-A (366 nm, 390 nm, 402 nm) light-emitting diodes supplementing basal (447 nm, 638 nm, 665 nm and 731 nm) enlightment. Research methods: The Hypocotyls and the height of the ground segment of the plant was measured using callipers. The amount of green mass (mg) was determined weighing the ground segment of the plant with scales. The area of leaves (cm2) was measured using the measuring instrument of leaf area. The amount of saccharides (raffinose, sucrose, glucose, mannose, fructose) was defined by the method of liquid chromatography. Nitrates were defined by potentiometric method. Photosynthetic pigments (chlorophyll a and b) was determined by spectrophotometry method according to Wetshtein. Research results: After investigation of the influence of aditional UV-A light-emitting diode on biometric indicators of microgreens, it was determined that... [to full text]

A fim de colaborar com o conhecimento dos vários aspectos das diferentes populações e suas interações para o manejo e conservação dos recursos naturais, foram analisadas a dinâmica populacional e a dieta de três espécies do gênero Stellifer (Sciaenidae), coletadas de agosto de 2003 a outubro de 2004 em áreas rasas da Enseada de Caraguatatuba, com influência mínima dos rios e estuários da região. Os indivíduos de Stellifer rastrifer (n=3183), S. brasiliensis (n=357) e S. stellifer (n=116) concentraram-se em geral na porção sul da enseada e houve diferença entre o tamanho das três espécies (S. rastrifer > S. stellifer > S. brasiliensis), que apresentaram um padrão de variação do comprimento ao longo do tempo bastante semelhante. Todas se mostraram essencialmente carcinófagas, com variação sazonal dos itens alimentares e alta sobreposição alimentar entre elas. Stellifer rastrifer permitiu uma análise de aspectos reprodutivos e de crescimento. A quantidade de fêmeas com gônadas em maturação e maduras foi muito pequena, bem como os valores do índice gonadossomático foram baixos indicando que a área não seja usada para desova. Os valores estimados para os parâmetros de crescimento (L?=20,9, K=0,37 e Z=2,81) indicam que haja uma segregação espacial entre jovens e adultos e que a taxa de mortalidade encontrada deva incluir em sua composição uma elevada taxa de migração dos jovens para áreas mais profundas, onde se supõe que completem seu desenvolvimento. / Intending to collaborate with some knowledge about ecosystems functioning for its suitable management and the conservation of natural resources, it was analyzed the populational dynamics and diet of three species belonging to the genus Stellifer (Sciaenidae), collected from August 2003 to October 2004, in shallow areas of Caraguatatuba Bay, where there was the least influence as possible of rivers and estuaries placed in the region. Species were Stellifer rastrifer (n=3183), S. brasiliensis (n=357) and S. Stellifer (n=116), wich focused at the southern area of the Bay. Species were significantly different from each other for size (S. rastrifer > S. stellifer > S. brasiliensis), although they have shown a quite similar pattern of length variation over time. They all fed upon basically crustaceans, with marked seasonal variation of food items and high dietary overlap among them. Stellifer rastrifer abundance allowed reproductive aspects analysis and the determination of growth parameters. The number of mature gonads in females was very small and gonadosomatic index values throughout the year were low, thus indicating that it is not a sapwn area. The growth parameters calculated (L?=20.9, K=0.37 and Z=2,81) indicate that there is a spatial segregation by size and that the mortality rate must, therefore, include a high rate of older individuals migration to deeper areas, where it is assumed that they complete their development.

A fim de colaborar com o conhecimento dos vários aspectos das diferentes populações e suas interações para o manejo e conservação dos recursos naturais, foram analisadas a dinâmica populacional e a dieta de três espécies do gênero Stellifer (Sciaenidae), coletadas de agosto de 2003 a outubro de 2004 em áreas rasas da Enseada de Caraguatatuba, com influência mínima dos rios e estuários da região. Os indivíduos de Stellifer rastrifer (n=3183), S. brasiliensis (n=357) e S. stellifer (n=116) concentraram-se em geral na porção sul da enseada e houve diferença entre o tamanho das três espécies (S. rastrifer > S. stellifer > S. brasiliensis), que apresentaram um padrão de variação do comprimento ao longo do tempo bastante semelhante. Todas se mostraram essencialmente carcinófagas, com variação sazonal dos itens alimentares e alta sobreposição alimentar entre elas. Stellifer rastrifer permitiu uma análise de aspectos reprodutivos e de crescimento. A quantidade de fêmeas com gônadas em maturação e maduras foi muito pequena, bem como os valores do índice gonadossomático foram baixos indicando que a área não seja usada para desova. Os valores estimados para os parâmetros de crescimento (L?=20,9, K=0,37 e Z=2,81) indicam que haja uma segregação espacial entre jovens e adultos e que a taxa de mortalidade encontrada deva incluir em sua composição uma elevada taxa de migração dos jovens para áreas mais profundas, onde se supõe que completem seu desenvolvimento. / Intending to collaborate with some knowledge about ecosystems functioning for its suitable management and the conservation of natural resources, it was analyzed the populational dynamics and diet of three species belonging to the genus Stellifer (Sciaenidae), collected from August 2003 to October 2004, in shallow areas of Caraguatatuba Bay, where there was the least influence as possible of rivers and estuaries placed in the region. Species were Stellifer rastrifer (n=3183), S. brasiliensis (n=357) and S. Stellifer (n=116), wich focused at the southern area of the Bay. Species were significantly different from each other for size (S. rastrifer > S. stellifer > S. brasiliensis), although they have shown a quite similar pattern of length variation over time. They all fed upon basically crustaceans, with marked seasonal variation of food items and high dietary overlap among them. Stellifer rastrifer abundance allowed reproductive aspects analysis and the determination of growth parameters. The number of mature gonads in females was very small and gonadosomatic index values throughout the year were low, thus indicating that it is not a sapwn area. The growth parameters calculated (L?=20.9, K=0.37 and Z=2,81) indicate that there is a spatial segregation by size and that the mortality rate must, therefore, include a high rate of older individuals migration to deeper areas, where it is assumed that they complete their development.

This M.Sc. thesis is aimed to describe growth and production parameters of nematophagous fungus Arthrobotrys oligospora. There was determinated information about growth and sporulation of fungus on artificial and natural substrates, influence of cultivation condition on production biomass and possibility of formulation alginate pellets.

Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-02-20T17:57:53Z No. of bitstreams: 2 Tese - Carla Eloiza B. C. Seabra.pdf: 1211089 bytes, checksum: 1125d30550099fb430808207eb415619 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-02-20T17:58:36Z (GMT) No. of bitstreams: 2 Tese - Carla Eloiza B. C. Seabra.pdf: 1211089 bytes, checksum: 1125d30550099fb430808207eb415619 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-02-20T17:59:00Z (GMT) No. of bitstreams: 2 Tese - Carla Eloiza B. C. Seabra.pdf: 1211089 bytes, checksum: 1125d30550099fb430808207eb415619 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-02-20T17:59:00Z (GMT). No. of bitstreams: 2 Tese - Carla Eloiza B. C. Seabra.pdf: 1211089 bytes, checksum: 1125d30550099fb430808207eb415619 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-07-29 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Mahogany (Swietenia macrophylla King) is in high demand world-wide, and is one of Brazil’s most highly valued forestry species. Balsa (Ochroma pyramidale Cav. ex. Lamb.) also has broad usage and great market potential owing to extremely rapid growth rates. Rather than harvesting these increasingly rare timber species from native forests, high density commercial plantings have been established. However, there is little information concerning the nutritional requirements of both species, especially regarding the response to soil phosphorous (P). Phosphorous is expensive in Brazil and over use is associated with adverse environmental consequences. In this study, we examined the effects of four levels of P fertilization (0, 1, 10 and 100 kg ha-1) on biometric and physiological parameters of mahogany and balsa wood seedlings grown in the greenhouse. The response to P was markedly different for the two species. For mahogany, seedling height, seedling diameter, leaf area, leaf weight, stem dry weight, and total dry weight increased at the 100 kg/ha-1 P level. The greatest increase (3- to 5- fold) occurred for leaf area and leaf weight, whereas root dry mass was not influenced by P. Similarly, %N and %P (but not %C) in leaf, stem and root tissue increased with increasing P level, but increased drastically at the 100 kg/ha-1 P treatment. The divalent cations (Ca and Mg) increased in foliar tissue, yet the concentrations of organic acids in xylem fluid declined with increasing P. Leaf macro- and micro-nutrients concentrations were influenced by P treatments, with the exception of Zn and Fe. Leaf, stem and root P utilization efficiency was highest at the 0, 1 or 10 level. Root phosphatase activity was unaffected by P level. By contrast, balsa responded greatly to increasing P concentration, although the most dramatic increase was at 100 kg/ha-1. For example, there was a 9-, 4-, 66-, 25-, 65-, 25- and 32-fold increase for seedling height, seedling diameter, leaf area, leaf dry mass, stem dry mass, root dry mass, and total dry mass, respectively, for the 0 compared to the 100 kg/ha-1 treatment. Leaf, stem and root %N decreased and %P increased with increasing P levels. Macro and micro nutrient levels wereinfluenced by P treatment, with the exception of Mn. The concentrations of organic acids in xylem fluid were altered by P fertilization; and malic, succinic, and lactic acids were highest at the 100 kg/ha-1 treatment. Leaf, stem and root P utilization efficiency increased greatly with increasing P level; however, root phosphatase activity decreased with increasing P levels. The implications of these physiologic data are discussed in relation to management strategies for the culture of mahogany and balsa. / Plantios comerciais de mogno e pau-de-balsa, com maiores relações custo/benefício, podem alavancar o mercado de madeira de espécies nativas, tanto interno quanto externo. Mogno e pau-de-balsa estãoentre as mais valiosas espécies de madeira com diversos usos, sendo ambas economicamente promissoras. Todavia, informações sobre a influência do fósforo (P) na nutrição e desenvolvimento das mesmas são incipientes. Em condições de casa de vegetação, avaliou-se os efeitos de quatro doses de P (0; 1; 10 e 100 kg ha-1) sobre parâmetros biométricos e fisiológicos dessas espécies. Para mogno, as doses crescentes de P elevaram o crescimento da parte aérea, os conteúdos de carbono, nitrogênio, P e, as concentrações foliares de macronutrientes e manganês, e diminuíram a eficiência de utilização de P, as concentrações foliares de boro e cobre e, a concentração dos ácidos orgânicos no fluido do xilema. Não foi verificado efeito sobre o crescimento de raiz, as concentrações foliares de Zn e Fe, e a atividade de fosfatase de raiz. Destaca-se que houve correlação inversa entre a atividade de fosfatase ácida de raiz e o crescimento da parte aérea e, P e N acumulados na planta. Para pau-de-balsa, o aumento das doses de P elevou o crescimento da parte aérea, a eficiência de utilização de P e a concentração de ácidos orgânicos no fluido do xilema. As concentrações foliares de nutrientes foram afetadas de forma variada pela aplicação de doses de P: P, magnésio e cálcio aumentaram e, nitrogênio, potássio, enxofre, boro, zinco e cobre diminuíram. Doses crescentes de P diminuíram a atividade de fosfatase ácida de raiz. Não foi verificado efeito sobre as concentrações foliares de manganês, ferro e do ácido oxálico no fluido no xilema. Em geral, doses crescentes de P melhoram a formação das mudas dessas espécies. Porém, uma adubação equivalente a 100 kg P ha-1 pode causar desequilíbrio de crescimento em mudas de pau-debalsa.

Thesis (M.Sc. (Animal Production)) -- University of Limpopo, 2023 / The development curve of Venda chicken fed with various amounts of citric acid was evaluated using nonlinear models in an experiment. to ascertain the effects of citric acid supplementation level on feed intake, body weight increase, and linear measurements on Venda chickens. 200 male Venda chickens were used in the experiment which lasted 90 days. The chicks were randomly assigned to four treatments (0, 12.5, 25 and 50g of citric acid inclusion) with 5 replications, resulting in 20 floor pens with 10 chicks per replicate. A completely randomized design was employed as experimental design. Analysis of Variance (ANOVA) was used to determine the effect of citric acid on feed intake, body weight gain, FCR, GR and body linear measurements. Three different non-linear models, namely Gompertz, Weibull, and Richards, were used to define the growth curves of the Venda chickens. The Duncan multiple range test at the 5% level of significance was utilized to detect significant differences between the means. Models were compared using coefficients of determination (R2) and standard errors (SE). The results indicated that feed intake, body weight, average daily gain and growth rate of Venda chickens were not affected (p > 0.05) by citric acid supplementation levels. Similarly, Citric acid supplementation had no effects (p > 0.05) on the shank length and wing length of Venda chickens. However, feed conversion ratio (FCR) of Venda chickens was improved (p < 0.05) by with an increase in citric acid supplementation. The Venda chicken fed citric acid at grower phase and finisher phase had better growth performances than the starter phase. Citric acid supplementation improved the back length and thigh length of Venda chickens. The Venda chickens fed citric acid at 25g inclusion level significantly higher back and thigh length. The coefficient of determination ranged from 0.00 to 0.98 in all the treatments. The Gompertz Model and Richards Models both exhibited the same coefficient of determination across all treatments. The model with the lowest standard error was found to best describe the growth curve of male Venda across all treatments. The Gompertz model was observed to be suitable for explaining the growth of Venda chickens fed with feed without citric acid (CA0g) and citric acid 125g inclusion (CA12.5g). The Richards model was observed to be suitable for explaining the growth of Venda chickens fed citric acid 25g inclusion (CA25g) and citric acid 50g inclusion (CA50g). It is recommended to use a supplement containing lower citric acid to enhance the body linear measurements and growth performance of the chickens. Gompertz and Richards models can be utilized to characterize the growth curve of Venda chickens. / National Research Foundation (NRF)

A pesquisa visou a avaliar o processamento de imagens digitais pelo Sistema TreeVis (SVA) para identificar o estado nutricional de plantas de milho com níveis induzidos de Ca; Mg e S em plantas de milho (Zea mays L.). Foram utilizados tratamentos constituídos pela omissão completa e individual dos nutrientes Ca, Mg e S e para cada nutriente foram avaliadas doses crescentes (1/3, 2/3 e completa) do elemento e 4 repetições. Esse experimento foi realizado em casa de vegetação sob cultivo hidropônico, conduzido em vasos com solução nutritiva. Foram determinados os parâmetros de crescimento da cultura do milho (altura da planta, número de folhas e diâmetro do colmo) e massa seca das plantas. Foram feitas amostragens de plantas em V4, V6 e V8, visando determinar os teores de macro e micronutrientes das raízes e parte aérea e observados a sintomatologia de deficiência das plantas. Nesses estádios, através de um sistema de visão artificial, também foram obtidas as imagens das folhas. A omissão de Ca, Mg e S na solução nutritiva promoveu sintomas típicos de deficiência de cada nutriente em plantas de milho. O sistema de visão artificial conseguiu identificar os sintomas de deficiência de Ca, Mg e S com 80%, 75,5% e 78% de acertos, respectivamente. / The research aimed to evaluate the processing of digital images by TreeVis System (AVS) to identify the nutritional status of corn plants with induced levels of Ca, Mg and S in corn (Zea mays L.). Treatments used were made by the individual and complete omission of Ca, Mg and S and for each nutrient were evaluated escalating doses (1/3, 2/3 and complete) element and four replications. This experiment was conducted in a greenhouse under hydroponic cultivation in pots with nutrient solution. It was determined the growth of corn (plant height, leaf number and stem diameter) and plant dry. Samples were collected from plants in V4, V6 and V8 engines, to determine the levels of macro and micronutrients from the roots and shoots and observed symptoms of deficiency of plants. In these stages, through an artificial vision system, images were also obtained from the leaves. The omission of Ca, Mg and S in the nutrient solution caused symptoms typical of each nutrient deficiency in maize plants. The artificial vision system could identify the symptoms of deficiency of Ca, Mg and S with 80%, 75.5% and 78% accuracy, respectively.

FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / O presente trabalho tem por objetivo a caracterizaÃÃo dos aspectos tecnolÃgicos e da composiÃÃo das capturas, complementados com estudos sobre o crescimento e a alimentaÃÃo das principais espÃcies na pesca de atuns e afins em cardumes associados no AtlÃntico Oeste Equatorial. Para tanto, foram acompanhados 109 desembarques em Areia Branca, RN, no perÃodo entre jun/2010 e mai/2013, assim como o embarque em nove cruzeiros de pesca no perÃodo entre fev/2011 e dez/2012. O estudo de idade e crescimento, foi realizado com base nas leituras de anÃis etÃrios nos espinhos dorsais e microincrementos diÃrios de otÃlitos de Thunnus albacares ajustados aos modelos de crescimento de von Bertalanffy, Gompertz e LogÃstico, os quais foram selecionados a partir dos valores de AIC (Akaikeâs Criterion Information). O estudo de alimentaÃÃo foi desenvolvido por meio da identificaÃÃo e avaliaÃÃo dos itens alimentares presentes no conteÃdo estomacal de T. obesus e T. albacares. Foram observadas 9 embarcaÃÃes, com comprimento total mÃdio de 13,4 m, as quais utilizam diversas tÃcnicas de captura como a linha de mÃo, vara e linha, corrico e corso, com o uso de iscas artificiais e naturais. Os desembarques totalizaram 691.533 kg de pescado, dentre os quais, as espÃcies alvo foram a albacora bandolim e a albacora laje, sendo retidas tambem espÃcies como o dourado, agulhÃo negro, bonito-listrado, cavala empinge, peixe rei e ainda, ocasionalmente, espÃcies como espadarte e cangulo. Os valores de L &#773;_&#8734; foram estimados em 175,13 e 171,6 cm para os dados observados e retrocalculados a partir dos espinhos dorsais e em 166,6; 171,14; e 155,38 cm respectivamente para os dados agrupados, para machos e fÃmeas a partir dos microincrementos diÃrios de otÃlitos. Os principais itens alimentares observados na dieta de ambos os predadores foram os peixes das famÃlias Myctophidae, Exocoetidae, Bramidae e Nomeidae, sendo observadas com menor frequÃncia os cefalÃpodes e os crustÃceos. Podemos concluir que os resultados obtidos fornecem informaÃÃes essÃnciais que ajudarÃo a compreender as atividades de pesca, bem como ampliarÃo os conhecimentos sobre a biologia das principais espÃcies capturadas. / The present study aims to characterize the technolo gical features and the catch composition, complemented with studies on the age a nd growth and feeding of the target species in the fishery for tunas in associated schools in the western equatorial Atlantic. For this purpose, a total of 109 landings by the fleet based on Areia Branca, RN, were observed in the period from June 2010 to M ay 2013, as well as on board in nine fishing cruises in the period from February 2011 to December 2012. The age and growth study was performed based on readings of age rings of the dorsal spines and daily microincrements present in the otolith of Thunnus albacares, adjusted to von Bertalanffy , Gompertz and Logistic growth models, which were selected based on their AIC (Akaike 's Information Criterion) valu es. The feeding study was developed through the identification and assessment of food items present in the stomach contents from T. obesus and T. albacares . The fleet consisted of 9 boats, with an average length overall of 13.4 m, which use various fishing techniques such as handline, rod and line and trolling, combined with natural baits or lures. Landings amounted 691,533 kg, from which, the target species were bigeye and yellowfin tunas, as well as bycatch, species such as dolphinfish, blue marlin, skipjack, wahoo, rainbow runner and, even occasionally, species such as swordfish and triggerfish. The values of L were estimated at 175.13 and 171.6 cm for the obser ved and backcalculated data from the dorsal spines and 166.6, 171.14 and 155.38 cm, respectively for the pooled data, males and females based on otolith daily microstructure. The main food items observed in the diet of both predators were the following fish families: Myctophidae, Exocoetidae, Bramidae and Nomeidae. Cephalopods and crustaceans were occasionally observed. We can conclude that results provide essential information that will ass ist in the understanding of fishing activities as well as expand the knowledge on the biology of the target species.