Orientador: Elton Eustáquio Casagrande / Manoel Fernando Martins / Ana Claudia Fernandes Terence / Resumo: A cadeia de carne bovina possui posição de destaque no contexto da economia rural brasileira, ocupando vasta área do território nacional e respondendo pela geração de emprego e renda de milhões de brasileiros. Contudo, para atender as demandas da sociedade moderna, é preciso avançar na produção de produtos mais diferenciados. Neste sentido, ganham relevância as estratégias empresariais nos diversos elos da cadeia produtiva da carne bovina, sobretudo no subsistema de industrialização. Na cadeia produtiva da carne bovina brasileira, um dos programas de destaque com essa finalidade é o Programa Carne Angus Certificada. Este trabalho, classificado como uma pesquisa aplicada, de natureza exploratória, de abordagem qualitativa, no contexto de uma análise de interação setorial, feita através de um procedimento de estudo multicaso, descreveu e analisou a estrutura competitiva e o comportamento estratégico dos frigoríficos participantes do Programa Carne Angus Certificada em São Paulo, com suporte das teorias do Modelo das Cinco Forças de Porter e das Tipologias Estratégicas de Miles e Snow. A coleta de dados se deu através de entrevista semiestruturada, realizada com quatro indústrias frigoríficas participantes do programa no estado, que contou com roteiro pré-determinado e perguntas avaliativas feitas após as respostas dadas com auxílio de itens da escala Likert (estrutura competitiva) e respostas às questões de múltipla escolha (comportamento estratégico). Os resultados para a estr... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The beef production chain has a prominent position in the context of the Brazilian rural economy, occupying a large area of the national territory and responding to the generation of employment and income for millions of Brazilians. However, to meet the modern society demands, it is necessary to move forward in the production of differentiated products. In this sense, corporate strategies gain importance in the beef production chain channels, especially in the industrialization subsystem. In the Brazilian beef production chain, one of the main programs for this purpose is the Certified Angus Beef Program. This work, classified as an applied research, of an exploratory nature, with a qualitative approach, in the context of a sectorial interaction analysis, made through a multicase study procedure, described and analyzed the competitive structure and strategic behavior of the meatpackers participating in the Program Angus Beef Certified in São Paulo, with support from Porter's Five Forces Model theories and Miles and Snow Strategic Typologies. Data were collected through a semistructured interview, conducted with four meatpacking industries participating in the program in the state, which had a predetermined script and evaluative questions made after the answers given using Likert scale items (competitive structure) and responses to multiple choice issues (strategic behavior). The results for the competitive structure indicated that the threat of new competitors and the power o... (Complete abstract click electronic access below) / Mestre

The thesis is focused on the growth intensity of Aberdeen Angus, Charolais and Limousine. In experiment A, 152 male animals were monitored. These bulls came from organic and conventional breeding. For bulls, the date of birth, birth weight, father's line, date of sale, and live weight of bulls at sale were followed. Experiment B included 88 female heifers. Within each breed heifers came from conventional and organic breeding. Heifers were monitored for birth date, birth weight, father's line, weight at 120 and 210 days. Significant differences (p < 0.01) were found in the evaluation of the weights of individual monitored parameters between bulls and heifers, which are confirmed by the rule that females have lower birth weight (37 kg) than males (40 kg). However, at 120 days of age, weights were higher in heifers (177 kg) compared to bulls (148 kg). In the evaluation of breeding effect, the highest (p < 0.01) weights were found in Charolais (bulls 163 kg, heifers 187 kg).

Data from 946 Angus and 351 Simmental females were used to quantify relationships between calfhood and early-life traits of females with fertility in the first two breeding seasons, and with calf production in the first, in three and in eleven years of life. These traits were used to develop prediction equations for fertility using logistic regression methodology. For productive performance, three methodologies were compared: least squares, ridge regression and principal components regression. For heifers of both breeds, fertility was associated with birth date, weaning weight ratio and weaning-yearling relative growth rate (RGR). The only calfhood trait that consistently affected fertility in the second breeding season was birth weight of the cow. Fertility of first parity Simmentals was also associated with birth-yearling RGR. First calving season traits explained a higher proportion of variation in second breeding season fertility than calfhood traits of the cow. Among these traits, calving date, calving ease score and sex of the calf were the most important. The combination of birth date and weaning-yearling RGR produced the best models to predict heifer fertility for both breeds. Fertility in the second breeding season was best predicted for Angus cows when calving date, calving ease score and sex of the calf were used as regressors. For Simmental cows, fertility in the second breeding season was best predicted from birth weight of the calf and calving ease score. The regression of weaning weight of the first calf on pre-selected calfhood traits was used to evaluate models produced by least squares, ridge regression and principal components regression. Although biased, the regression coefficient estimates produced by ridge and principal components regression had smaller variances than estimates obtained from least squares. Between the two alternatives to least squares, ridge regression produced better results than principal components regression. Ridge and least squares regression were quite similar in their regression coefficient estimates, in prediction sum of squares (PRESS)-like statistics and, to a lesser extent, in conceptual predictive criteria (C_p)-like statistics. For prediction, the performance of models produced by least squares and by ridge regression were very similar. For analyses of the production traits, least squares regression models for all possible combinations of pre-selected regressor variables were fit. Birth date of the female was negatively associated with the weaning weight of the first calf, and with number of calves weaned, total weaning weight of calves produced and average weaning weight of calves in the first three years of productive life. Age of the dam affected early-life production traits of daughters, as well as the average weaning weight of calves produced per year of productive life and calf survival in eleven years. Heavier females at birth tended to produce smaller number of calves and lower calf weaning weight through their lives than females lighter at birth. Overall female productivity was consistently more positively associated with yearling than with weaning growth traits. Among traits observed in the first calving season, calving date, calving ease score, sex and weaning weight of the calf were associated with subsequent production. Weaning weight of the first calf was always positively associated and it was the most important variable to predict female production, except for survival rate. Prediction equations for production in three years included birth date, birth weight of the female, calving ease in the first parturition, sex of the calf and weaning weight of the first calf. This latter variable was the only one useful to predict production in eleven years. Average calf weaning weights in the first three years of production were best predicted using yearling weight ratio or weaning-yearling ADG and first calf weaning weight. Models including age of the female’s dam best predicted weaning weight of calves per year of productive life in eleven years and calf survival. / Ph. D.

The objectives of this study were: (1) to estimate the effects of certain non-genetic sources of variation in weight, gnde, and condition of beef cows; (2) to estimate the heritability of weight, grade. and condition of beef cows; and (3) to estimate the genetic, phenot;rpic, and environmental correlations between weight, grade, and condition of beef cows. Weights, grades., and condition scores taken on 1371 Angus cows were used to evaluate the genetic and environmental nature of these traits. This sample of cows represented 365 sire groups. Four models were used in this study: 1. Model A - Cow weight and grade were considered dependent variables; herds and sires within herds were considered random independent variables; and season, age, condition, nursing status, and their interactions were considered fixed independent variables. Least-squares procedures involving Henderson's (1953) Method II were used to adjust tor fixed effects and to obtain variance and covax-iance components. Heritability estimate and correlation coefficients were obtained by paternal half-sib analysis. 2. Model B differed from Model A in that condition 3 score was considered a dependent variable instead of an independent variable. 3. Model C was the same as Model A except that the coefficients (kₒ and k₂) for the within sire (σw²) component of variance included in the among sire and herd adjusted expected mean squares (EMS) were considered unity whereas as in Model A they were calculated according to Method II of Henderson. 4. Model D - Heritability estimates were computed by doubling the estimate of intra-sire regression of offspring on dam from 198 dam-daughter pairs representing 63 sire groups. The dam-daughter pairs were part of the group or 1371 cows. The results of this study indicated that season, age, condition score, nursing status, and age by nursing status remain significant when condition score was not considered as a fixed environmental effect (Model B). However, a comparison of the magnitude of the mean squares for these effects in Models A and B indicated that season, age, and nursing status are highly confounded with condition score. Season and flesh condition were found to have a significant effect on grade of beef cows when they were included in the same model (Model A). When condition score was not included (Model B) age had a significant effect on grade. Age, season, and nursing status were found to have a significant effect on flesh condition (Model B). Paternal half-sib heritability estimates for cow weight using Models A, B, and C were 0.38 ± 0.11, 0.29 ± 0.11, and 0.56.± 0.11, respectively. Estimates for grade from the same models were 0.49 ± 0.11, 0.43 ± 0.11, and 0.67 ±0.12, in that order. Estimates from Model A should be the most reliable. The differences in the estimates from Models A, B, and C, illustrate that variation in heritability estimates is not entirely due to genetic differences. Considerable variation can occur depending on how much adjustment has been made to fixed effects, and the methods used in estimating the variance and covariance components. The heritability estimates of cow weight and grade obtained by intra-sire regression of offspring on dam were 0.22 ± 0.14 and 0.10 ± 0.06, respectively. The paternal half-sib heritability estimate for condition score was 0.31 ± 0.11, which implies that adjusting cow weights and grades for condition may actually involve adjusting for genetic differences as well as differences due to environmental influences. The correlation between weight and grade or beef oowe was found to be largely genetic whereas the correlation between condition and cow weight or grade was primarily environmental. / Ph. D.

Thesis (M.A.)--Carleton University, 2000. / Includes bibliographical references.

Thesis (M.S.W.)--University of Hong Kong, 1987.

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 50-52). Also available on the World Wide Web.

Orientadores: Paula Regina Kuser Falcão, Adhemar Zerlotini Neto / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-27T05:46:03Z (GMT). No. of bitstreams: 1 Nagai_LuisAugustoEijy_M.pdf: 9861948 bytes, checksum: a64a8aaaf5e43919029e865524c0a73c (MD5) Previous issue date: 2015 / Resumo: A carne bovina é um dos principais produtos que o Brasil comercializa no mercado internacional. Atualmente, o Brasil é líder nas exportações e tem o objetivo de melhorar sua produção para aumentar a competitividade. A carne bovina é consumida em várias partes do mundo e é uma das principais fontes de proteínas e vitaminas para o homem. A publicação em 2009 do genoma bovino, proveniente de um animal da subespécie Bos taurus taurus, beneficiou os estudos de caracterização de mecanismos moleculares responsáveis por características de interesse. Dentre várias características, a maciez da carne é considerada o atributo mais importante. As raças zebuínas, principalmente Nelore (Bos taurus indicus), possuem grande aceitação na pecuária de corte brasileira e adaptabilidade ao território, porém apresentam menor produtividade e qualidade da carne, em relação às raças taurinas como Angus (B. taurus taurus). Assim, o interesse pela identificação de genes relacionados com a qualidade da carne bovina justifica o investimento em pesquisas genéticas, moleculares e bioquímicas. As novas tecnologias de sequenciamento de alto rendimento promoveram um grande avanço nas pesquisas de avaliação da expressão de genes, aliada às novas ferramentas computacionais e o poder de processamento de dados. O objetivo deste trabalho é identificar genes diferencialmente expressos no tecido muscular de animais das raças Angus e Nelore, para elucidar os mecanismos genéticos envolvidos com maciez da carne. Para realizar este estudo foram utilizados 10 bovinos da raça Angus e 8 bovinos Nelore, a partir de um rebanho de 50 touros de cada raça, selecionados pelos extremos no resultado do teste de força de cisalhamento. Ao todo, 313 milhões de fragmentos de 100 pares de bases foram gerados em Illumina HiScanSQ paired end. Ao longo desse estudo, foi também avaliada a utilização de sequências originais e filtradas por qualidade para estimar a eficácia das ferramentas atuais ao trabalhar com sequências que comumente são trimadas. As sequências foram mapeadas no genoma bovino utilizando Tophat2 e a biblioteca edgeR foi utilizada na análise estatística para a identificação de expressão diferencial. Os resultados encontrados nos animais Angus, com sequências não filtradas, se mostraram mais semelhantes com o que tem sido observado em trabalhos relacionados à maciez da carne, os quais indicam o envolvimento da via de metabolismo de lipídeos no mecanismo de maciez. Contudo, os dados de Angus e Nelore possibilitaram a identificação de processos de resposta imune e inflamatórias, que poderiam ter sido influenciados por fatores externos pré abate / Abstract: Brazil is one of the largest beef exporters in the world, and beef quality is a major subject of research. The goal of this research is to improve the quality and productivity of Brazilian livestock. Beef is also an important source of protein and vitamins in human nutrition. Publication of The Bos taurus genome in 2009 has contributed to studies on the characterization of molecular mechanisms responsible for traits of interest, however, much remains to be determined. Among the many traits of interest, meat tenderness is the most important measured attribute. The Zebu breeds, particularly Nelore (Bos taurus indicus), have wide acceptance in the Brazilian market, and they are well adapted to tropical conditions. Nevertheless, Zebu cattle have lower productivity and beef quality when compared to Taurine breeds, such as Angus (Bos taurus taurus). The global market interest in the identification of genes involved in beef quality justifies the importance of research of genetic, molecular and biochemical mechanisms that determine this trait. The objective of this study is to identify differentially expressed genes found in the muscle tissue of Angus and Nelore breeds. To obtain the data to do this gene expression study, ten Angus steers and eight Nelore steers were used, they were chosen from a group of fifity animals of each breed, and were selected for their extreme tenderness and toughness scores on the shear force test. In total, 313 million fragments of a 100 base pairs were generated using Illumina HiScanSQ paired end. In parallel with the gene expression study, the use of trimmed or non-trimmed sequences was determined to evaluate the efficiency of the tools that have been used to filter this background noise. All sequences were mapped to the bovine genome using Tophat2, and the edgeR library provided the statistical analysis used to identify differential expression. Results obtained from the analysis of the data from the Angus breed animals with non filtered sequences are consistent with results observed in studies of beef tendernes. This finding implies the involvement of the lipid metabolism pathway in the biochemical mechanism underlying the improved tenderness. However, Nelore data analysis identified the existence of processes involved in inflammatory/immune response; they may have been influenced by external factors prior to the slaughter / Mestrado / Bioinformatica / Mestre em Genética e Biologia Molecular

published_or_final_version / Architecture / Master / Master of Landscape Architecture

published_or_final_version / Architecture / Master / Master of Architecture