959 resultados para Productive and reproductive traits


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Wildlife living in the suburbs faces the challenge of dealing with human presence and yard management (including the occurrence of pets) which vary at the scale of the house block. This study examined the influence of ecological factors (e.g. extent of grass and food availability) and anthropogenic factors (e.g. human activity and garden usage) on breeding site choice and reproductive success of the ground-nesting masked lapwing Vanellus miles on Phillip Island, Australia. Lapwings nested less frequently in residential properties (high levels of human usage) compared with vacant blocks and holiday houses. They were also more likely to breed on properties with high food availability and larger areas of grass. None of these variables influenced clutch size or the probability of eggs hatching, although larger clutches and higher hatching rates tended to be associated with more food. This study shows that, for an urban exploiting species, habitat quality is not homogenous at the scale of the house block, and that human activity is avoided by a species generally considered highly tolerant of people.

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This chapter discusses private equity and venture capital (PE/VC) in Brazil. Firstly, it is shown that PE/VC has a strong impact in the Brazilian capital markets, with PE/VC-backed companies representing close to half the amount raised by initial public offerings (IPOs) in the stock exchanges. By examining two of these deals, which involved small and mediumsized enterprises (SMEs), it is argued that PE/VC managers have acted as catalysts of the impressive growth rates experienced before these companies entered the stock markets. Indeed, PE/VC firms represent an important segment of the capital market, with specialization to invest in high-growth innovative SMEs. PE/VC managers exercise superior selection, monitoring and governance that mitigate the uncertainty and risks of investing in such companies. Despite its successes in Brazil, PE/VC is still very much restrained by the challenging local economic and institutional environment. Thus, changes in the legal and fiscal system, simplification in bureaucratic procedures, and other such improvements will most likely result in a sensible growth in the Brazilian PE/VC industry, with positive impact in the SME access to finance in Brazil. Since most countries in Latin America share similar economic and institutional traits with Brazil, the path followed by the local PE/VC industry can serve as an example for other countries to learn with its successes and failures.

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The study proposed to describe sexual development in pelagic stage loggerhead sea turtles Caretta caretta and compare this to hatchlings and adults. It is meant as an ontogenic approach, in order to understand reproductive development and population composition and their dynamics in the pelagic environment. The study focused on the pelagic loggerheads that are found in the waters offshore Madeira Island (Portugal) in the North-eastern Atlantic and use it as a developmental habitat. The innovating character of this work relied on the lack of any description regarding the gonad ontogenesis and reproductive development for the pelagic stage in any of the 7 existing sea turtle species, all of them in danger of extinction. Three methods were used to diagnose the sex of each juvenile individual and asses the level of reproductive development: (1) laparoscopy, (2) gonad biopsy and (3) the assessment of two sex steroids circulating levels, namely testosterone and estradiol. In order to cover all life stages and compare data obtained for the juvenile stage, hatchlings and nesting female adults were sampled at the nearest nesting rookery at Boa Vista Island in the Cape Verde Archipelago. Gonads from dead hatchlings were collected for gonad histology and blood was collected from nesting females for sex steroids assessment. Laparoscopies revealed to be a valid sexing method for the juvenile stage, since gonads are morphologically differentiated at these size classes. Moreover, laparoscopy was validated using gonad histology. Gonad histology of juveniles showed that gonads are already completely differentiated into ovaries or testes at the size classes examined, but development seems to be quiescent. Males present already developed seminiferous tubules with spermatogonia lining the interior of the seminiferous tubule. Female gonads present oocytes at different development stages, but only oocytes up to stage III were observed. The maximum oocyte diameter in each individual correlated with body size, suggesting that reproductive development is an on-going process in juvenile females. The circulating levels of both testosterone and estradiol in juveniles of both sexes were very low and consistently lower than the ones observed in the nesting females from Boa Vista Island. No bimodal distribution was found for any of the sex steroids analysed and thus circulating hormone levels were not a reliable tool for sexing juvenile individuals with a non-invasive technique. The ratio testosterone:estradiol did not show a bimodal distribution either. The levels of testosterone correlated with sea surface temperature. The fact that temperatures observed during this study were below 24ºC might have hindered a differential testosterone pattern between juvenile males and females. Sex ratios for this population were generated according to laparoscopy results and compared among years and size classes. An overall sex ratio of 2 females for each male was found, but they varied among size classes but not among years. Possible causes for the sex ratios observed are discussed. This study is a contribution to our knowledge on the pelagic stage of loggerhead turtles, namely on the population structure regarding sex ratio, which is a vital tool for implementing conservation strategies.

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Sexually transmitted diseases (STDs) are among the largest public health problems, especially in developing countries. The acquisition of these infections during early sexual activity is common and many infections have a benign course. However, in some pathogens remain in the state of latency can be reactivated and cause productive infection that may progress to severe forms. In addition, some of them are transmitted vertically resulting in congenital infection, causing immediate damage or long-term child. The classic risk factors for sexually transmitted agents are: early onset of sexual and reproductive health, multiple sexual partners throughout life, use of oral contraceptives and co-infections with different pathogens. We present the results of a cross-sectional study aimed to estimate the prevalence of genital infection by human papillomavirus (HPV), Herpes simplex virus (HSV) and Chlamydia trachomatis (CT) in a segment of the female population of the metropolitan area Christmas, among those who enrolled voluntarily sought, Basic Health Units for the examination of cancer screening cervix in the period 2008 to 2010. All participants, a total of 261 women answered a standard questionnaire by which identified the socio-demographic characteristics, classical risk factors for STDs, reproductive and sexual activity and smoking. Of each patient were obtained two samples, one for the completion of the Pap test for detection of cellular changes and the other processed for DNA extraction and analyzed by PCR (polymerase chain reaction) to detect the three pathogens studied. The population of the study was composed of sexually active women aged between 13 and 79 years, mean 38.7 years, most of them being married, low education levels and low incomes. The majority (87%) had normal results on cytology and only 2.7% had low-grade cytological abnormalities. Prevalence rates were 37.9% for HPV, 4.6% for CT and 26% for HSV. HPV prevalence was higher in women under 25, unmarried and in those who had multiple sexual partners. Women with simultaneous infection by HSV-1 and 2 had higher prevalence of HPV infection. The prevalence of HSV infection showed no association whatsoever with the risk factors analyzed and HSV-1 was the predominant type among the cases of genital HSV infection. The overall prevalence of C. Trachomatis was relatively low, thus providing greater value in younger women aged less than or equal to 20 years

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Este estudo foi realizado para descrever o efeito da reversão sexual de linhagens de tilápia sobre as taxas de sobrevivência, o crescimento e o percentual de machos fenotípicos em condições ambientais variáveis. Foram utilizadas duas linhagens de Oreochromis niloticus (tilápia-do-nilo comum e tailandesa) e uma híbrida Oreochromis sp (vermelha), que receberam o hormônio masculinizante 17-α-metiltestosterona incorporado à ração (60 mg/kg) durante os primeiros 30 dias de vida. Aos 90 dias de idade, a taxa de sobrevivência da tilápia-do-nilo comum superou a da tilápia tailandesa em 39,00% e da tilápia vermelha em 22,70%, enquanto a taxa instantânea de crescimento foi similar nas linhagens comum e tailandesa e significativamente inferior na linhagem vermelha. O percentual de machos, de acordo com o exame de gônadas, decresceu na seguinte ordem: tilápia-do-nilo comum, tailandesa e vermelha. em situações de oscilação de temperatura, a linhagem comum tem maior desempenho produtivo, mas são necessários estudos para comprovação da pureza genética e análise do manejo reprodutivo de linhagens de tilápia.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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A melancia é uma espécie tradicionalmente conduzida em campo no sistema rasteiro. As cultivares de frutos pequenos (1 a 3 kg), que adquirem melhores preços de mercado, vêm sendo cultivadas também em ambiente protegido, onde são conduzidas no sistema vertical, com poda de ramos e raleio de frutos. Essas práticas possibilitam aumentar o adensamento das plantas, a qualidade e a produtividade de frutos em comparação ao sistema rasteiro. Objetivou-se com este trabalho avaliar a influência de três alturas de condução (1,7; 2,2 e 2,7 m) e duas densidades de plantas (3,17 e 4,76 plantas m-2) sobre as características produtivas e qualitativas da mini melancia Smile cultivada em ambiente protegido. A poda da haste principal foi realizada aos 43, 55 e 66 dias após o transplante (DAT) para as alturas de condução de 1,7; 2,2 e 2,7 m, respectivamente. A massa seca dos ramos, dos pecíolos, das folhas e total foram afetados pela altura de condução, cujos maiores valores foram obtidos para as plantas conduzidas a 2,2 e 2,7 m de altura. A área foliar, a área foliar específica e o índice de área foliar não foram influenciados pela altura de condução das plantas. A altura de condução de 2,7 m elevou a produtividade total. Entretanto, a produtividade comercial, a massa média dos frutos e todas as características qualitativas não foram significativamente diferentes das obtidos pela altura de poda de 2,2 m. em relação à densidade de plantas, a melhor opção foi a de 4,76 plantas m-2, pois elevou a produtividade comercial em 37,4% sem reduzir a massa média dos frutos.

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The lacewings appear in many agroecosystems, preying several species of agricultural pests. They have great search capability, high voracity, high reproductive potential and are easily maintained in laboratory conditions. In laboratory rearing, to avoid problems in the mass production are recommended adjustments in the type and quality of prey to be used in order to obtain individuals with desirable characteristics. It is necessary special care with the laboratory populations, avoiding problems from inbreeding. Larvae were reared individually in Petri dishes (9.0 cm diameter) and fed with eggs of Sitotroga cerealella (Olivier, 1789) (Lepidoptera: Gelechiidae), in the amount of 25 mg / larva, while the adults were kept in PVC cylindrical cages (10 cm x 30 cm). Thus, the study analyzed the influence of the size of the population of Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) on the pre-imaginal period (egg to adult) and reproductive capacity of this specie come from different populations and generations of laboratory. To this end, we used two populations, one of Jaboticabal (F-8 and F-21) and one of Piracicaba (F-6 and F-15), and subpopulations of 1, 5, 10, 15 and 20 couples, analyzing the incubation of eggs and the number of eggs per female in each population, generation and subpopulation. The pre-imaginal period (egg to adult) and the number of eggs per female of C. externa are influenced by the generation and the number of founding individuals, being these parameters favored when laboratory populations are established with the largest number of couples.

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Foram investigados os efeitos das características do pelame e da taxa de sudação (TS) sobre o intervalo de partos (IEP, n = 423) e os dias para o parto (DPP, n = 1.202) de vacas da raça Braford criadas em sistema extensivo em região tropical úmida no Mato Grosso do Sul, Brasil. As análises foram realizadas pelo método dos quadrados mínimos considerando para intervalo de partos os seguintes efeitos das classes de idade da vaca ao parto: grupo genético; pai; e regressão sobre a refletância da superfície da capa (R), a espessura da capa (E), o comprimento dos pêlos (C), o número de pêlos por unidade de área (N), o diâmetro dos pêlos (D) e a taxa de sudação. Para dias para o parto, foram considerados os efeitos: R, E, C, N, D, TS, divididos em classes; grupo genético; idade no início da estação de monta; e pai. Os componentes de variância e co-variância foram estimados pelo método de Máxima Verossimilhança Restrita sob o modelo touro. As características adaptativas não foram importantes para a variação do intervalo de parto e dos dias para o parto, mas a taxa de sudação apresentou efeito importante sobre dias ao parto. As estimativas de herdabilidade foram quase nulas para IEP e DPP e maiores para as características adaptativas (E = 0,16 ± 0,09; C = 0,18 ± 0,09; N = 0,08 ± 0,06; D = 0,12 ± 0,07; R = 0,30 ± 0,12; TS = 0,10 ± 0,06). Os resultados obtidos para as correlações genéticas de IEP e DPP com TS e entre as características do pelame indicaram que a seleção simultânea para menores valores de C pode ser favorável à redução do intervalo de partos. em geral, as correlações genéticas entre TS, IEP e DPP apresentaram elevado erro-padrão. Considerando os resultados deste estudo e a importância das características do pelame e da sudação, confirma-se a necessidade de se estudarem as correlações genéticas entre as características adaptativas e o desempenho reprodutivo para o progresso da adaptação de bovinos da raça Braford no Brasil.

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The objective of the present study was to evaluate the effects of different dietary energy levels and stocking densities on the thermoregulating parameters, live performance, and carcass traits of broilers reared under tropical winter conditions at different times of the day. In total, 1,312 one-d-old male broilers were used. Birds were allotted to three different stocking densities (10, 14 or 18 birds/m²) and two dietary energy levels (2900 or 3200 kcal ME/kg). The following parameters were evaluated:radiant heat load (RHL), rectal temperature (RT), feed intake (FI), weight gain (WG), feed conversion ratio (FCR), livability (L), production of live weight per area (WA), and carcass yield. Stocking density did not affect sensible heat loss (SRL) or rectal temperature (RT); however, as expected, sensible heat loss (SRL) and RT were influenced by time of the day, with higher values in the morning and in the afternoon, respectively. There was no effect of treatment (p>0.05) on carcass or parts yield. Feed intake was reduced in 3%, whereas weight gain and feed conversion ratio improved in 8 and 10%, respectively, as dietary energy level increased. on the other hand, stocking density did not influence live performance or carcass traits. Based on the present results, it is concluded that sensible heat loss depends on dietary energy levels and particularly on time of the day. Therefore, environmental house management is suggested during tropical winters in order to reduce differences between broiler skin and environmental temperatures in the morning and in the afternoon.

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Com o objetivo de avaliar o desempenho de quatro genótipos de soja-hortaliça, em dois anos agrícolas, foi instalado um ensaio, em área da UNESPFCAV, Campus de Jaboticabal-SP. O delineamento experimental adotado foi de blocos casualizados, com quatro genótipos e cinco repetições, para cada ano agrícola. Cada parcela experimental foi constituída por quatro linhas de plantio, com 3 m de comprimento, dispostas no espaçamento de 0,10 m entre plantas e 0,60 m nas entrelinhas, sendo consideradas para avaliação 20 plantas por parcela, das duas linhas centrais. As sementes foram semeadas em bandejas de poliestireno expandido de 128 células, contendo substrato Plantmax Hortaliças®. O transplante ocorreu dez dias após a semeadura, sendo que o solo já estava devidamente preparado, conforme recomendações para a cultura. A colheita foi realizada quando as vagens estavam em estádio reprodutivo R6. Avaliaram-se os genótipos: JLM003; JLM010; JLM018 e CNPSoI quanto às características: altura de inserção da primeira vagem, número médio de vagens por planta, número médio de sementes por vagem, produção de vagens por planta, massa fresca de 100 sementes e produtividade estimada de grãos imaturos. de acordo com os resultados obtidos, concluiu-se que, dentre os genótipos avaliados, JLM003, JLM010 e CNPSoI foram os mais produtivos, e quando semeados em dezembro apresentam produtividades maiores do que quando semeados em setembro.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)