958 resultados para Nelore (Zebu) - Reprodução
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Climate change in tropical countries, like Brazil, causes major problems in dairy production due to an increase of heat stress effects. In recent years, milk production in Brazil increased 36.07%. The Southeast region remains a leader in production with herds of high producing Holstein cattle (mostly), which is more susceptible to heat stress. Thermal stress decreases fertility in direct and indirect ways. Conception rates are reduced of 40-60% during cooler months of the year and 10-20% in the warmer months. Negative effects of heat stress involve changes in reproductive hormones, follicular development, oocytes, and embryos, and decreased dry matter intake. Several studies discuss change in reproductive hormones, such as reduction in plasma concentration of GnRH, LH, and oestradiol, which lead to decreased detection of estrus and ovulation. Various methods are being studied to bypass these negative effects and increase the fertility of dairy cows under heat stress. Cooling systems are the most advantageous and can be associated with technologies such as ET and TAI
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In the last years Brazil has achieved a leading position in worldwide cattle breeding. This country is consolidating the practice of an intensive and technical level cattle breeding, due to greater emphasis on reproductive efficiency and genetic improvement. The attention given to reproductive efficiency became to enhance the genetic improvement process, by exploiting the full reproductive potential of the animals. The biotechniques applied to reproduction arised to expand the reproductive potential for greater economic return. Are the most important reproductive biotechniques the FTAI and in vivo and in vitro embryo production for embryo transfer. Different hormonal treatments are consolidating to interfere with normal physiology in order to achieve the desired goals. The FTAI works to increase the reproductive rates of cattle through pre-booked artificial insemination in all the females in reproduction, without the need for estrous detection. The in vivo and in vitro embryo production aims to distribute the genetics of males and females genetically improved by transferring their embryos to genetically inferior females. Superovulation treatments designed to prevent the mechanism of dominance, which results in many follicles ovulating simultaneously for in vivo embryo production. To the in vitro embryo production, the technique of ovarian puncture guided by transvaginal ultrasound allows to aspirate a number of quality oocytes. The application of biotech is based on knowledge of the female and ovarian reproductive physiology and knowledge of their acting in different breeds and environments.
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Experimental models are necessary to elucidate pathophysiological mechanisms not yet understood in humans. To evaluate the repercussions of the diabetes, considering two methodologies, on the pregnancy of Wistar rats and on the development of their offspring. In the 1st induction, female offspring were distributed into two experimental groups: Group streptozotocin (STZ, n=67): received the β-cytotoxic agent (100mg STZ/kg body weight - sc) on the 1st day of the life; and Non-diabetic Group (ND, n=14): received the vehicle in a similar time period. In the adult life, the animals were mated. After a positive diagnosis of pregnancy (0), female rats from group STZ presenting with lower glycemia than 120 mg/dL received more 20 mg STZ/kg (ip) at day 7 of pregnancy (2nd induction). The female rats with glycemia higher than 120mg/dL were discarded because they reproduced results already found in the literature. In the mornings of days 0, 7, 14 and 21 of the pregnancy glycemia was determined. At day 21 of pregnancy (at term), the female rats were anesthetized and killed for maternal reproductive performance and fetal development analysis. The data were analyzed using Student-Newman-Keuls, Chi-square and Zero-inflated Poisson (ZIP) Tests (p<0.05). STZ rats presented with increased rates of pre (STZ=22.0%; ND=5.1%) and post-implantation losses (STZ=26.1%; ND=5.7%), reduced rates of fetuses with appropriate weight for gestational age (STZ=66%; ND=93%) and reduced degree of development (ossification sites). Conclusion: Mild diabetes led a negative impact on maternal reproductive performance and caused intrauterine growth restriction and impaired fetal development
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A pesquisa teve como objetivo central identificar e analisar as diversas estratégias de permanência e reprodução social dos produtores familiares e os efeitos do Programa Nacional de Fortalecimento da Agricultura Familiar (PRONAF) no município de Urânia - SP. Constata-se que as atividades desenvolvidas externamente a unidade produtiva e principalmente a previdência social rural são importantes na composição da renda dos produtores familiares. Mas, as principais estratégias são de base agrícola, visto que as atividades agropecuárias constituem-se na principal fonte de renda dos produtores familiares, destacando-se a opção por culturas que proporcionam alta rentabilidade por hectare cultivado, tais como: as frutíferas (uva, laranja, caju, dentre outras) e olerícolas (berinjela, jiló, milho verde etc.). Nesse sentido, a relevância das atividades agropecuárias, principalmente a fruticultura, em especial a uva que demanda grandes investimentos em tecnologia, despesas em insumos faz com que o PRONAF desempenhe importante papel para o desenvolvimento das atividades agropecuárias através das modalidades de custeio e investimento no conjunto de produtores familiares pesquisados, apesar de suas limitações no que tange a marginalização de produtores menos capitalizados e atuação exclusivamente vinculada à concessão de crédito. Identificamos que a gestão profissionalizada é um importante elemento para o progresso econômico da unidade produtiva, proporcionando condições mais favoráveis à permanência do produtor familiar na atividade agrícola e a sucessão hereditária na agricultura familiar, que perfaz a minoria dos casos em função da resistência dos jovens em permanecer no espaço rural decorrentes da baixa rentabilidade e de outros fatores como a penosidade do trabalho...(Resumo completo, clicar acesso eletrônico abaixo)
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Pós-graduação em Medicina Veterinária - FCAV
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Pós-graduação em Ciência e Tecnologia Animal - FEIS
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Pós-graduação em Ciência e Tecnologia Animal - FEIS
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Pós-graduação em Agronomia - FEIS
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Pós-graduação em Ciências Biológicas (Zoologia) - IBB
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A bovinocultura é um dos principais destaques dentro do universo pecuário brasileiro e mundial, uma vez que o rebanho nacional é detentor do expressivo número de 200 milhões de cabeças entre as atividades de corte e leite, produzindo um valor bruto estimado em 67 bilhões de reais. Ainda assim, a pecuária de corte nacional apresenta baixos índices produtivos por continuar sendo conduzida, ao menos em considerável parcela do país, como uma atividade extrativista que emprega reduzido uso de insumos e biotecnologias, como inseminação artificial, transferência de embriões, fertilização in vitro e inseminação artificial em tempo fixo. No atual cenário mundial, essa característica da bovinocultura brasileira necessita ser alterada para que a atividade torne-se ainda mais rentável e competitiva. Neste caso, a pecuária de corte nacional terá que se apoiar no aumento de sua eficiência reprodutiva e produtiva, tendo como principais alternativas para atingir tal objetivo a elevação do número de vacas com estro no início da estação de monta, o aumento na taxa de concepção no primeiro serviço e a redução no intervalo entre partos, de improdutivos 21 meses para um ano, tempo considerado ideal e de máxima eficiência reprodutiva de um rebanho. Assim sendo, torna-se imprescindível elencar os principais fatores prolongadores do intervalo entre partos para, somente depois, instituir um ou mais métodos para se reduzir essa eficiência reprodutiva e finalmente impulsionar ainda mais a pecuária bovina brasileira
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Com o crescimento significativo da pecuária bovina brasileira houve o aumento de pesquisas e estudos que buscam animais cada vez mais precoces e produtivos. O presente trabalho é uma revisão de literatura com base em trabalhos que demonstram a eficiência da suplementação energética na maturação sexual de novilhas Nelore, visando a melhora da eficiência reprodutiva e antecipação da puberdade
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Pós-graduação em Biociências - FCLAS
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This paper discusses urban space focusing on the housing sector, the capitalist reproduction and some changes occurring in that space as a result of the dynamics of the real estate sector and interests of financial agents, developers and urban land owners/speculators. The changes imposed to cities value abstract spaces over concrete ones, showing the unbalance between the interests of agents, who have in view the market, and those of dwellers, who live daily in such areas. Based on these reflections, a case study was carried out in the Jardim Letícia neighborhood in Leme city (state of São Paulo) in order to understand the space production and reproduction in that area, analyze some of the main problems faced by local people, and identify some agents involved in the process.
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The historical and social process has built models of masculinity and femininity that culminate in standards and norms to be followed by individuals in their social interactions. In recent decades studies based on the discussions that originated in the feminist movement have been investigating how social institutions, including medicine and other health sciences, have established standards of masculinity and femininity throughout the history, nurturing this sexist discourse on common sense and sciences. Social roles are assigned to the genera specifying rigid boundaries of behavior and social control. The notion of the female predisposition to physical and emotional disorders has prompted speculation within academic strands culminating in the creation of specialized medical illness that would prevent the female, the male permeated by notions of endurance and strength has become synonymous of a healthy body, confirming the male domination and the economic and political role of men. This research concerned to study and investigate through semi-structured interviews and content analysis, conceptions of gender and the differences between men and women in reports of 11 health professionals. The results indicate that in large part the conceptions of health professionals reproduce the hegemonic discourse about what being a man and woman. Further research could investigate the relationship between women and men with health care as well the care provided by health professionals