Made available in DSpace on 2014-06-11T19:32:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-11-19Bitstream added on 2014-06-13T21:05:22Z : No. of bitstreams: 1 missio_rl_dr_jabo.pdf: 805386 bytes, checksum: fd72382d10b76ace86d683f99af93f1d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este estudo objetivou avaliar o armazenamento da cana-de-açúcar hidrolisada com 0,5% de cal hidratada sobre o consumo das frações alimentares, desempenho animal, viabilidade econômica, comportamento ingestivo, características nutritivas da forragem e aspectos da digestão de novilhas confinadas. Foram realizados dois experimentos. No primeiro (Capítulo 2 e 3), foram utilizadas 24 novilhas da raça Nelore distribuídas inteiramente ao acaso nos tratamentos formados por dietas com cana-de-açúcar in natura (tempo zero), cana-de-açúcar hidrolisada e armazenada por 24, 48 ou 72 horas. No segundo (Capítulo 4), foram utilizadas quatro novilhas da raça Nelore delineadas num quadrado latino 4x4, onde foram avaliadas as dietas anteriormente descritas. No primeiro experimento, verificou-se variação cúbica (P < 0,05) em função do tempo de armazenamento da cana-de-açúcar da maioria das variáveis relacionadas ao consumo das frações alimentares e desempenho animal, apresentando melhores resultados para novilhas alimentadas com cana-de-açúcar in natura. O armazenamento da cana-de-açúcar até 72 horas proporcionou aumento linear (P < 0,05) da fração de carboidratos potencialmente degradáveis e diminuição dos custos de produção. Novilhas alimentadas com dietas a base de cana-de-açúcar in natura apresentaram maior tempo de ruminação (P < 0,05). No segundo experimento, verificou-se que o consumo e digestibilidade dos nutrientes, o balanço de nitrogênio, a eficiência de síntese de proteína microbiana e o nitrogênio amoniacal não foram influenciados (P > 0,05) pelas dietas. O armazenamento da cana-de-açúcar com adição de 0,5% de cal hidratada até 72 horas deprime o consumo e desempenho de novilhas jovens da raça Nelore / This study evaluated the effect of storage of hydrolyzed sugarcane with .5% hydrated lime the dietary fractions intake, animal performance, economic viability, ingestive behavior, nutritional characteristics of forage and digestion aspects of confined heifers. Two experiments were conducted. In the first (Chapter 2 and 3), 24 Nellore heifers were used and randomly distributed in treatment formed by diets constituted by fresh sugarcane (zero time), hydrolyzed sugarcane and stored for 24, 48 or 72 hours. In the second (Chapter 4), four heifers were used constituting a 4x4 latin square, with similar diets previous. In the first experiment, there was variation cubic (P < .05) according the storage time of most variables related to dietary fractions intake and animal performance, with better results for heifers fed with fresh sugarcane. Storage of sugarcane until 72 hours promoted linear increased (P < .05) in the carbohydrate fraction potentially degradable and decreased production costs. Heifers fed diets with fresh sugarcane presented higher time ruminating (P < .05). In the second experiment, it was found that the intake and digestibility of nutrients, the nitrogen balance, the efficiency of microbial protein synthesis and the ammonia nitrogen were not affected (P > .05) by diets. The storage of hydrolyzed sugarcane with .5% of hydrated lime up to 72 hours depresses intake and performance of young Nellore heifers

Made available in DSpace on 2014-06-11T19:32:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-01Bitstream added on 2014-06-13T19:03:45Z : No. of bitstreams: 1 ribeiro_tmd_dr_botfmvz.pdf: 1175902 bytes, checksum: e83fea39c577b1ede76fa2c826ee8e78 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O trabalho objetivou avaliar as características da pastagem de Azevém sobressemeada em Tifton-85 e a produtividade de cordeiros desmamados submetidos a três níveis de suplementação. Os cordeiros pastejaram azevém sobressemeado em Tifton-85 e foram avaliados de acordo com a suplementação recebida: sem suplementação, suplementação em 0,9% do peso corporal (PC), suplementação em 1,8% PC e suplementação ad libitum. Os cordeiros foram pesados a cada 14 dias com jejum prévio de 16 horas. O método de utilização da pastagem foi o de pastejo com lotação contínua e taxa de lotação variável, procurando manter a altura da pastagem em 15 cm, sendo mensurada a cada 7 dias. A taxa de crescimento da pastagem foi mensurada pela técnica do triplo emparelhamento. Foi calculada a disponibilidade de forragem, o número de cordeiros/ha e a carga animal. O ganho de peso médio diário aumentou linearmente com a elevação do nível de suplementação concentrada oferecida aos cordeiros. Os níveis de suplementação concentrada tiveram relação linear negativa com a taxa de acúmulo, a matéria seca acumulada e a disponibilidade de matéria seca da forragem; e relação quadrática com a altura da pastagem, a taxa de lotação de cordeiros/ha e a carga animal (kgPC/ha). Concluise que a suplementação dos cordeiros em pastagem proporcionou melhor ganho de peso diário dos animais. Os níveis de suplementação interferem na altura e na disponibilidade de forragem. O efeito de substituição da pastagem pelo concentrado promoveu diminuição do crescimento da pastagem e da produção acumulada de forragem. Níveis de suplementação ad libitum possibilitaram aumentar o número de animais/ha e a carga animal / This study objected to evaluate ryegrass pasture characteristics oversowned on Tifton-85 and the performance of grazing weaned lambs supplemented in three levels of concentrate. The lambs grazed in ryegrass oversowned on Tifton-85 and were evaluate according to the supplementation that they had fed: no supplementation (control), 0,9% of body weight (BW), 1,8% of BW and ad libitum. The animals were weighted to each 14 days with 16 hour of water fasting. Grazing management was continuous variable stocking to keep pasture in 15 cm, being taken every 7 days. The herbage accumulation rate was measuredby triple cage technique. Availability of forage, number of lambs per hectare and animal stocking were calculated. The average daily weight gain increase linearly with increasing levels of concentrate supplementation offered to lambs. The level of concentrate supplementation had a negative linear relation with herbage growth rate, accumulated dry mater and available forage dry matter; and a quadratic relation with pasture height, number of lambs per hectare and animal stocking rate (kgBW/ha). It could be concluded that supplementation for grazing lambs provided better daily weight gain animals. The levels of supplementation interfered in height and availability of forage. The effect of substitution of grazing for concentrate promoted decreased of pasture daily growth and availability of forage dry matter. Levels of supplementation ad libitum increase number of animal/ha and animal stocking

In a world with an increasing flow of written information online and offline, the demand for automatic translation, simplification and summarization technology is growing. The tool StilLett uses several lexical and semantic rules to automatically simplify text, shortening the time from original text to simplified text compared to manual simplification. Four of the simplification types were evaluated in this study, using three different eye tracking measures; total dwell time, number of regressions, and average fixation duration. No statistically significant differences were found for any of the simplification types when compared to the corresponding original sentences, indicating that for this population the difficulty of the sentences was roughly the same.

Cette thèse porte sur la génération aléatoire uniforme des automates finis et l'analyse des algorithmes de minimisation qui s'y appliquent. La génération aléatoire permet de conduire une étude expérimentale sur les propriétésde l'objet engendré et sur les méthodes algorithmiques qui s'y appliquent. Il s'agit également d'un outil de recherche, qui permet de faciliter l'étude théorique du comportement moyen des algorithmes. L'analyse en moyenne des algorithmes s'inscrit dans la suite des travaux précurseurs de Donald Knuth. Le schéma classique en analyse d'algorithmes consiste à étudier le pire des cas, qui n'est souvent pas représentatif du comportement de l'algorithme en pratique. D'un point de vue théorique, on définit ce qui se produit "souvent'' en fixant une loi de probabilitésur les entrées de l'algorithme. L'analyse en moyenne consiste alors à estimer des ressources utiliséespour cette distribution de probabilité. Dans ce cadre, j'ai travaillé sur des algorithmes de génération aléatoire d'automatesdéterministes accessibles (complets ou non). Ces algorithmes sont basés sur de la combinatoirebijective, qui permet d'utiliser un procédé générique : les générateurs de Boltzmann. J'ai ensuite implanté ces méthodes dans deux logiciels : REGAL et PREGA. Je me suis intéressé à l'analyse en moyenne des algorithmes de minimisation d'automateset j'ai obtenu des résultats qui montrent le cas moyen des algorithmes de Moore et Hopcroft est bien meilleur que le pire des cas / This thesis is about the uniform random generation of finite automata and the analysisof their state minimization algorithms. Random generators allow to conduct an experimental study on the properties of the generated objectand on the algorithms that apply to this object. It is also a useful tool for research that facilitates the theoretical study of the average behavior of algorithms. Usually, the analysis of an algorithm focuses on the worst case scenario, which is often not representative of thepractical behavior of the algorithm. From a theoretical point of view, one can define what happens "often" by fixing a probability law on the algorithm's inputs. The average analysis consists in the estimation ofthe requested resources, according to this probability distribution.In this context, I worked on several algorithms for the random generation of deterministic accessibleautomata (complete or not).Those algorithms are based on bijective combinatorics, that allows to use generic tools called the Boltzmann generators. I implemented those methods in two softwares : REGAL and PREGA. I studied the average complexity of state minimization algorithms and obtained results showing that theaverage case of the two algorithms due to Moore and Hopcroft is way better than the worst case

abstract: Current sensing ability is one of the most desirable features of contemporary current or voltage mode controlled DC-DC converters. Current sensing can be used for over load protection, multi-stage converter load balancing, current-mode control, multi-phase converter current-sharing, load independent control, power efficiency improvement etc. There are handful existing approaches for current sensing such as external resistor sensing, triode mode current mirroring, observer sensing, Hall-Effect sensors, transformers, DC Resistance (DCR) sensing, Gm-C filter sensing etc. However, each method has one or more issues that prevent them from being successfully applied in DC-DC converter, e.g. low accuracy, discontinuous sensing nature, high sensitivity to switching noise, high cost, requirement of known external power filter components, bulky size, etc. In this dissertation, an offset-independent inductor Built-In Self Test (BIST) architecture is proposed which is able to measure the inductor inductance and DCR. The measured DCR enables the proposed continuous, lossless, average current sensing scheme. A digital Voltage Mode Control (VMC) DC-DC buck converter with the inductor BIST and current sensing architecture is designed, fabricated, and experimentally tested. The average measurement errors for inductance, DCR and current sensing are 2.1%, 3.6%, and 1.5% respectively. For the 3.5mm by 3.5mm die area, inductor BIST and current sensing circuits including related pins only consume 5.2% of the die area. BIST mode draws 40mA current for a maximum time period of 200us upon start-up and the continuous current sensing consumes about 400uA quiescent current. This buck converter utilizes an adaptive compensator. It could update compensator internally so that the overall system has a proper loop response for large range inductance and load current. Next, a digital Average Current Mode Control (ACMC) DC-DC buck converter with the proposed average current sensing circuits is designed and tested. To reduce chip area and power consumption, a 9 bits hybrid Digital Pulse Width Modulator (DPWM) which uses a Mixed-mode DLL (MDLL) is also proposed. The DC-DC converter has a maximum of 12V input, 1-11 V output range, and a maximum of 3W output power. The maximum error of one least significant bit (LSB) delay of the proposed DPWM is less than 1%. / Dissertation/Thesis / Ph.D. Electrical Engineering 2011

Objetivou-se avaliar diferentes maneiras de manejar o campo nativo durante o período hibernal para alimentar ovelhas no inicio de gestação e determinar a melhor metodologia para tal fim, por meio das características produtivas e comportamentais dos animais assim como modificação na estrutura e qualidade da pastagem. Para tal, foram testados, com delineamento em blocos casualizados com quatro tratamentos e três repetições, dois métodos de pastoreio (contínuo (LC) e rotativo (LR)) e dois níveis de oferta de forragem (12 e 18% OF). As variáveis utilizadas para descrever as características produtivas dos animais foram: ganho médio diário das ovelhas e cordeiros, escore de condição corporal das ovelhas e o ganho de peso, em unidade de área, das ovelhas, cordeiros e o ganho total por área. Além destes, foram avaliados parâmetros de comportamento ingestivo, que são o tempo diurno de pastejo, ruminação e outras atividades, número, tamanho e intervalo de refeições, número, tempo e número de passos entre estações alimentares e taxa de bocados. As variáveis medidas no pasto foram: massa de forragem, taxa de acumulo, altura, massa de folhas verdes, colmos, leguminosas e “outras espécies”, e as características bromatológicas (proteína bruta, FDN, etc.) do pasto ao longo do tempo de duração do experimento. Os resultados apontaram que as OF, apesar de provocar modificações significativas na massa de forragem e altura do pasto, teve pouca influencia nos parâmetros de comportamento animal em pastejo e pouca influencia no desempenho produtivo dos animais, provavelmente devido ao baixo contraste que as ofertas de forragem intermediárias proporcionaram durante o inverno. Os métodos de utilização da pastagem também não apresentaram influência marcante sobre o desempenho produtivo das ovelhas, mas modificou drasticamente o comportamento ingestivo dos animais. Os animais manejados em LR apresentaram menores tempos de pastejo do que os animais mantidos em LC, e esse tempo variou também entre os dias de avaliação. A interação dos dois fatores não teve influência no peso dos cordeiros ao nascer, porém, influenciaram as características estruturais e bromatológicas do pasto. Onde no manejo no inverno foi constituído pelo método contínuo e 12% de OF, a pastagem apresentou uma menor quantidade de outras espécies e presença predominante de espécies de melhor qualidade, ficando mais “limpa” e melhor qualidade nutricional na primavera. Essa melhor qualidade nutricional, por sua vez, apesar de não modificar significativamente os ganhos individuais de ovelhas e cordeiros, modificou a quantidade de peso vivo produzido em unidade de área. / The main objective was to evaluate strategies to manage the grassland during the winter season to feed ewes at the early pregnancy and determine the best method for this purpose, through the animal production characteristics, their ingestive behavior as well as modification of the structure and quality of the pasture. The experiment was set up in a randomized block design with four treatments and three replicates, two grazing methods (continuous (CS) and rotational (RS)) and two levels of herbage allowance (HA; 12 - and 18% LW). The variables used to describe the animals performance were: average daily gain of sheep and lambs, ewes body condition score and weight gain in unit area of the sheep, lambs and total gain per area. It was also assessed parameters of ingestive behavior as the diurnal grazing time, ruminating and other activities, number , size and range of meals, number, time and step number between feeding stations and biting rate. The variables measured in the pasture was: herbage mass, accumulation rate, height, mass of green leaves, stems, legumes and 'other species' and nutritive characteristics values (crude protein, NDF, etc.) of the pasture over all time of duration of the experiment. The results showed that the HA, although cause some significant changes in herbage mass and sward height, had little influence on animal behavior parameters and little influence on the productive performance of animals, probably due to the low contrast that intermediate herbage allowance provided. The grazing methods also had no significant influence on the performance of the sheep, but dramatically changed the ewes grazing behavior. The smaller area in the RS promoted a shorter grazing time than the time observed on a CS, and the grazing time on RS also varied during the days. The interaction of the two factors did not influence the weight of lambs at birth, however, influence the structural and chemical characteristics of the pasture. Where the management in winter was constituted by CS and 12% HA, the pasture had a lower amount of other species, being “cleaner” and, also presents a better nutritional quality in the subsequent spring. This improved nutritional quality, in turn, while not significantly modify the ewes and lambs individual gains, changed the amount of weight produced on unit of area, been more productive than other combinations.

A determinação da rugosidade é parte fundamental para a classificação da qualidade de uma superfície. Assim, iniciou-se este trabalho realizando-se estudos a respeito de seus métodos de medição. Devido à grande adaptabilidade e à velocidade dos métodos a laser, os estudos foram direcionados para estes tipos de técnicas de medição. Verificou-se que esses dispositivos vinculavam-se a sistemas em que o laser refletido era analisado através de sistemas com detectores do tipo CCD, em que a imagem refletida era analisada num todo. Assim, a bibliografia trouxe inspiração para mensurar a rugosidade de uma superfície gerada por torneamento horizontal, a partir da intensidade laser refletida. Propôs-se, então, um método baseado exclusivamente, na intensidade do sinal que era refletido pela superfície em estudo, a contar de uma incidência normal, já que aos autores ressaltavam que quanto maior a rugosidade da superfície menor seria o sinal refletido por ela. O sistema foi montado e sua capacidade de diferenciar distintas rugosidades foi testada. Então foram produzidas amostras com diferentes rugosidades, a fim de se obter uma função que pudesse correlacionar o sinal laser com a respectiva rugosidade (medida esta feita em rugosímetro de agulha). A função de transferência encontrada foi testada em amostras dissemelhantes das que a geraram, com o intuito de comprovar sua eficácia. Amostras fabricadas com ferramentas distintas de corte também foram produzidas e submetidas ao mesmo procedimento. As funções de transferência geradas alcançaram sucesso na previsão da rugosidade em, no máximo, 16,6% dos pontos, considerando uma margem de erro de 20%. A seguir, procurando-se os motivos que pudessem ter causado este percentual, levantou-se a possibilidade de estarem ocorrendo efeitos ópticos capazes de causar interferências devido às irregularidades na superfície. Efeitos capazes de degenerarem o sinal refletido. A comprovação de que o sinal eventualmente poderia estar sendo perturbado aconteceu através de referência bibliográfica e de imagens obtidas por microscopia eletrônica de varredura, em que se pôde observar a existência de estruturas na face das amostras que seriam isolada ou conjuntamente capazes de causar os efeitos citados. / The determination of the roughness is a key for a good classification of a surface. Thereby, the work was started with a study about the roughness measurements methods. Due to the great adaptability and speed of laser methods, the studies were directed to these kinds of measurement techniques. It was observed in the literature that these laser devices were linked to systems where the reflected laser was analyzed by systems with CCD detectors, where the reflected image was entirely analyzed. Hence, the bibliography brought inspiration to measure the surface roughness generated by axial turning from the intensity of the reflected laser. It was proposed then a measurement method exclusively based on the intensity of the signal that was reflected by the surface under study, because the authors noted that as the roughness of surface became bigger as the signal reflected is became smaller. The proposed system has been assembled and ability to distinguish different roughness was tested successfully. Then samples were produced with different roughness in order to obtain a function that would correlate the laser signal with its roughness (this measurement is made by tactile measurement instrument). The transfer function obtained was tested on different samples that generated in order to prove its efficacy. Samples produced with different cutting tools were also produced and subjected to the same procedure. The transfer functions reached a successful prediction of the roughness maximum for 16.6% of the points assuming a margin of error of 20%. So, looking up the reasons that could have caused this percentage we think the possibility as the occurrence of some optical effects that can cause interference due to irregularities on the surface. These optical effects can degenerate the reflected signal. The proof that the signal could possibly be corrupted was made by the bibliographic references and some images obtained by scanning electron microscopy in which they could observe the existence of structures on the sample surfaces that would can be a reason for these effects individually or together.

O entendimento das relações entre as características do pasto e as respostas do comportamento ingestivo animal é fundamental para o aprimoramento de inovações no manejo de pastagens, tornando os sistemas pastoris mais eficientes e competitivos. Neste estudo comparamos dois métodos de pastoreio (Rotativo x Contínuo) e duas intensidades de pastejo (Moderada e Baixa) a fim de compreendermos como as características de pastos de azevém anual (Lolium multiflorum Lam.) influenciam o comportamento ingestivo e o ganho médio diário de ovinos. Observamos que o método de pastoreio afeta a quantidade de folhas e inflorescências, influenciando a composição química da forragem, além da taxa de bocados e o tempo de pastejo dos ovinos. Por outro lado, as intensidades de pastejo influenciaram os bocados por estação alimentar e o número de refeições. Além disso, variáveis como: estação alimentar por minuto, duração das refeições e tempo de pastejo foram positivamente correlacionadas com o ganho médio diário dos animais, assim, podem ser utilizadas como preditoras do ganho médio diário de ovinos. Encontramos evidências de que em pastoreio rotativo, ambas as intensidades de pastejo estudadas promoveram um rebaixamento em torno de 45% da altura pré-pastejo. A estrutura do pasto e a composição química da forragem foram adequadas para o pastejo de ovinos até o início do estádio reprodutivo do azevém anual. No entanto, ao final do estádio reprodutivo da pastagem, ambas as intensidades de pastejo restringiram os padrões de comportamento ingestivo dos ovinos nas maiores escalas espaço-temporais. Essa restrição é acentuada durante o rebaixamento do pasto, em decorrência da redução no percentual de lâminas foliares, alterando o comportamento ingestivo de ovinos. Logo, a resposta comportamental de ovinos depende de: (i) taxa de lotação, (ii) nível de desfolha do dossel, (iii) período do estádio reprodutivo do azevém anual e composição estrutural da forragem durante o rebaixamento. / The understanding of the relationships between sward characteristics and the animals' ingestive behavior responses is fundamental for the improvement of sward management innovations, making pastoral systems more efficient and competitive. In this study, we compared two stocking methods (Continuous and Rotational) and two grazing intensities (Moderate and Low) to understand how the sward characteristics of annual ryegrass (Lolium multiflorum Lam.) influence the ingestive behavior and the average daily gain of sheep. We observed that the stocking method affect the quantity of leaf blades and inflorescences influenced forage chemical composition, as well as the bite rate and grazing time of sheep. On the other hand, grazing intensities had influence the bites by feeding station and meals number. Moreover, variables as feeding station per minute, meals duration and grazing time were positively correlated with the average daily gain, thus, they can be used as predictors for the average daily gain of sheep. We found evidence that both grazing intensities studied promote a grazing down around 45% of pre-grazing sward height in rotational stocking. Sward structure and forage chemical composition, were adequate for sheep grazing until the beginning of the sward reproductive stage. However, from the stage 2 of grazing down at the end of the sward reproductive stage, both grazing intensities apparently restricted the sheep‟s ingestive behavior patterns in the larger spatial and temporal scales of grazing. Therefore sheep‟s behavioral response depends on: (i) stocking rate, (ii) canopy defoliation level, (iii) period of sward reproductive stage and forage structural composition during grazing down.

O objetivo do presente trabalho foi avaliar o desempenho reprodutivo de leitoas que foram selecionadas com baixos ganhos de peso diários (GPD) aos 160 dias de vida. Leitoas da linhagem Camborough® (n = 3301) foram alocadas em quatro grupos de acordo com o GPD no momento da seleção: G1 (n = 799) leitoas com GPD ≥480 a ≤ 530g/dia, G2 (n = 978) leitoas com >530 a ≤ 580g/dia, G3 (n = 916) fêmeas com >580 a ≤ 630g/dia e G4 (n = 608) leitoas com >630 a ≤ 810g/dia. Não foram encontradas diferenças na idade de início de estimulação com o macho e manifestação do primeiro estro entre as classes (P> 0,05). Na cobertura todos os grupos diferiram entre si sendo o G4 o grupo mais precoce e com maior peso (P< 0,05). O GPD da seleção até a cobertura diferiu entre as classes, sendo que o G1 teve maiores ganhos de peso quando comparado ao G3 e G4 respectivamente (P< 0,05). As médias de nascidos totais, nascidos vivos e intervalo desmame-estro não diferiram entre os grupos (P> 0,05). As remoções entre a seleção e a cobertura pós-desmame foram maiores no G1 e G2 quando comparados ao G4 (P< 0,05). Quando agrupados G1 e G2 e, a partir disso, formadas duas classes de acordo com o peso na cobertura (≤ 130 kg e > 130 kg), o grupo > 130 kg obteve 0,93 leitão a mais no primeiro parto (P< 0,05). Em conclusão, leitoas selecionadas com baixos GPDs (inferiores a 630g/dia) podem ser incorporadas no plantel sem gerar prejuízos no desempenho reprodutivo até o primeiro parto, desde que alcancem 130 kg no momento da cobertura. / The aim of this study was to evaluate the reproductive performance of gilts selected with low average daily gain (ADG) at 160 days of age. Camborough® gilts (n = 3301) were allocated into four groups according to ADG at selection: G1 (n = 799) represented the group of gilts with ADG ≥480-≤ 530g/day, G2 (n = 978) corresponded to gilts with >530- ≤ 580g/day, G3 (n = 916) represented the gilts with > 580-≤ 630g/day and G4 (n = 608) gilts with > 630-≤ 810g/day. There were no differences in the age at the onset of boar exposure and first estrus expression among groups (P> 0.05). Age and weight at insemination were different (P< 0.05) among groups. Gilts from G4 were inseminated earlier and heavier. The ADG from selection until mating was different among the groups, and G1 had greater weight gains when compared to G3 and G4 (P< 0.05). Total number of piglets born, number of piglets born alive and weaning to oestrus interval were not different among classes (P> 0.05). The removals since the selection until post-weaning insemination were higher in G1 and G2 when compared to G4 (P< 0.05). When gilts from G1 and G2 were grouped and categorized into two classes according to the weight at insemination (≤ 130 kg and > 130 kg), the heavier group (> 130 kg) had an increasing of 0.93 total born piglets at first farrowing (P< 0.05). The results of this study suggest that gilts selected with low ADG (less than 630g/day) could be incorporated into the breeding herd with no reproductive performance losses until the first farrowing if they reach 130 kg at insemination.

The aim of this diploma work was to analyse the results of the Aberdeen Angus meet oxherd breeding in an ecological farming with the welfare relationship to the animals and at the same time to compare the efficiency after the system change of the farming at the farm Angus, Rančice, owned by Šebelka. The research was done in the period of years 2006 ? 2011. The survey range includes 65 heads of thorough-bred cows as well as 204 heads of Aberdeen Angus calves born in the tracked period. The number of births, the birth process, and the age before lay out and related reasons were recorded by the cows. By the calves we noted the live mass and average daily gain in the growth process. The range of the calves was then sorted our by year of the birth, gender, rank of the birth, by genitors and by the way of farming. The data entries were elaborated in the MICROSOFT EXCEL and evaluated in STATISTICA 7 CZ. The number of spontaneous birth without cowman assist equals 94,12%, only 4,41% of births required the necessary support. By the monitored number of calves no matter of the gender was noted the lowest and the highest live mass by the birth in the year 2007 (36,81 kg resp. 38,77 kg). The group of calves born in 2010 reached the highest average weight in 120 days as well as in 210 days (192,27 kg resp. 309,04 kg). The lowest average weight in 120 days was noticed in year 2009 (168,96 kg), in 210 day in 2008 (262,31 kg). The best growth ability from the birth to 120 days was by the group of calves born in 2010 (1,409 kg) compared to the lowest result in 2009 (1,099 kg). The average daily gain from 120 till 210 days reached its minimum in 2009 (1,171 kg), the maximum numbers were noted in 2010 (1,412 kg). The growth intensity from the birth till 210 days circulated in the range of 1,071 kg (2008) and 1,377 kg (2010). In the ecological agriculture system were noted statistical better efficiency results (live mass, growth intensity) compared to conventional agriculture system.