Restricted intake and lipid inclusion in Santa Inês ewe lambs diet: age, weight and progesterone concentration at first ovulation.

Abstract: The age at first ovulation is influenced by several factors, and nutrition has an essential role on it. Lipids provide essential fatty acids that are positively associated to reproductive aspects. The aims of this study were to evaluate the effects of lipid inclusion and restricted intake on age and weight at the first ovulation and the serum progesterone (P4) concentration at the sixth day after first ovulation. Thirty-five Santa Inês ewe lambs with initial body weight (BW) of 21.5 ± 0.3 kg and age of 91.6 ± 1.4 days were used. Animals were blocked according to initial BW and distributed to one of four treatments: animals receiving diet without lipid inclusion (3.5% ether extract ? EE), ad libitum intake (WLI-ALI, control group, n = 9); diet without lipid inclusion and restricted intake (WLI-RI, n = 9); lipid inclusion diet, represented by toasted and broken soybean (9.8% EE), ad libitum intake (LIP-ALI, n = 8); and lipid inclusion diet and restricted intake (LIP-RI, n = 9). Ewe lambs subjected to restricted intake had 84% of the diet offered to those in ad libitum treatments. The individual daily dry matter intake (DMI) and EE intake (EEI) were measured and the animals were weekly weighted until 35 kg BW. For P4 analysis, blood samples were collected once a week after the animals reached 25 kg BW and twice a week after 30 kg until 35 kg BW. Ovulation was estimated to occur on the sixth day before P4 ?1 ng/mL. DMI, EEI, average daily weight gain until first ovulation (DWG), weight and age at first ovulation, serum P4 concentration and days in experiment until first ovulation were analyzed by GLM PROC of the SAS software (version 9.3). Ovulation occurred in 60% (21/35) of the ewe lambs (5; 5; 6; 5 from WLI-ALI; WLI-RI; LIP-ALI; and LIP-RI, respectively). DMI of ewe lambs from WLI-ALI group was greater (P 0.05) among WLI-ALI, WLI-RI, LIP-ALI, and LIP-RI treatments, respectively. The first ovulation in Santa Inês ewe lambs occurs at 30 kg BW. The restricted intake imposed in this study did not delay the age at fist ovulation. The greater lipid intake did not favor reproductive parameters. Serum P4 did not increase with the soybean inclusion in the diet. [Restrição alimentar e suplementação lipídica: idade, peso e concentração de progesterona até a primeira ovulação]. Resumo: A idade da primeira ovulação é influenciada por vários fatores e a nutrição tem um papel essencial. Lipídios fornecem ácidos graxos essenciais que estão associados de forma positiva aos aspectos reprodutivos. Os objetivos deste estudo foram avaliar os efeitos da inclusão lipídica e da restrição do consumo na idade e peso a primeira ovulação e na concentração sérica de progesterona (P4) no sexto dia após a primeira ovulação. Foram utilizadas trinta e cinco cordeiras Santa Inês com peso corporal (PC) inicial de 21,5±0,3 kg e idade de 91,6±1,4 dias. Os animais foram blocados de acordo com o PC inicial e distribuído a um dos quatro tratamentos: animais que receberam dieta sem inclusão de lipídeos (3,5% de extrato etéreo - EE), consumo ad libitum (SEM-ALI, grupo controle, n=9); dieta sem inclusão de lipídeos e restrição do consumo (SEMRE, n=9); dieta com inclusão lipídica, representada pela soja tostada e quebrada (9,8% EE), consumo ad libitum (LIP-ALI, n=8); e dieta com inclusão lipídica e restrição do consumo (LIP-RE, n=9). Cordeiras submetidas a restrição do consumo tiveram 84% da dieta oferecida em comparação aos tratamentos ad libitum. O consumo individual diário de matéria seca (CMS) e de EE (CEE) foram mensurados e os animais foram pesados semanalmente até 35 kg de PC. Para a análise de P4, amostras de sangue foram coletadas uma vez por semana depois que os animais atingiram 25 kg de PC e duas vezes por semana após 30 kg até 35 kg de PC. Estimou-se que a ovulação ocorreu no sexto dia que antecedeu P4?1 ng/mL. CMS, CEE, ganho de peso médio diário até a primeira ovulação (GPD), peso e idade da primeira ovulação, a concentração sérica de P4 e dias em experimento até a primeira ovulação foram analisados pelo PROC GLM do software SAS (versão 9.3). A ovulação ocorreu em 60% (21/35) das cordeiras (5; 5; 6; 5 do SEM-ALI; SEM-RE; LIP-ALI e LIP-RE, respectivamente). CMS de cordeiras do grupo SEM-ALI foi maior (P0,05) entre os tratamentos SEM-ALI, SEM-RE, LIP-ALI e LIP-RE, respectivamente. A primeira ovulação em borregas Santa Inês ocorreu com 30 kg de PC. A restrição do consumo imposta neste estudo não retardou a idade a primeira ovulação. A maior ingestão de lipídios não favoreceu os parâmetros reprodutivos. A P4 sérica não aumentou com a inclusão de soja na dieta.Proceedings of the 30th Annual Meeting of the Brazilian Embryo Technology Society (SBTE); Foz do Iguaçu, PR, Brazil, August 25th to 27th, 2016, and 32nd Meeting of the European Embryo Transfer Association (AETE); Barcelona, Spain, September 9th and 10th, 2016

Pyricularia are mostly host-specialized with limited reciprocal cross-infection between wheat and endemic grasses in Minas Gerais, Brazil.

Abstract: Wheat blast, caused by Pyricularia oryzae Triticum (PoT), is an emerging threat to global wheat production. Current understanding of the population biology of the pathogen and epidemiology of the disease has been based on phylogenomic studies that compared the wheat blast pathogen with isolates collected from grasses that were invasive to Brazilian wheat fields. In this study, we performed a comprehensive sampling of blast lesions in wheat crops and endemic grasses found in and away from wheat fields in Minas Gerais. A total 1,368 diseased samples were collected (976 leaves of wheat and grasses and 392 wheat heads) which yielded a working collection of 564 Pyricularia isolates. We show that, contrary to earlier implications, PoT was rarely found on endemic grasses and, conversely, members of grass-adapted lineages were rarely found on wheat. Instead, most lineages were host-specialized with constituent isolates usually grouping according to their host-of-origin. With regard to the dominant role proposed for signalgrass in wheat blast epidemiology, we found only one PoT member in 67 isolates collected from signalgrass grown away from wheat fields, and only three members of Urochloa-adapted lineages among hundreds of isolates from wheat. Cross-inoculation assays on wheat and a signalgrass used in pastures (U. brizantha) suggested that the limited cross-infection observed in the field may be due to innate compatibility differences. Whether or not the observed level of cross-infection would be sufficient to provide an inoculum reservoir, or serve as a bridge between wheat growing regions, is questionable and, therefore, deserves further investigation

A re-evaluation of phylogenomic data reveals that current understanding in wheat blast population biology and epidemiology is obfuscated by oversights in population sampling.

Abstract: Wheat blast, caused by the Pyricularia oryzae Triticum lineage (PoT), first emerged in Brazil and quickly spread to neighboring countries. Its recent appearance in Bangladesh and Zambia highlights a need to understand the disease's population biology and epidemiology so as to mitigate pandemic outbreaks. Current knowledge is mostly based on characterizations of Brazilian wheat blast isolates and comparison with isolates from non-wheat, endemic grasses. These foregoing studies concluded that the wheat blast population lacks host specificity and, as a result, undergoes extensive gene flow with populations infecting non-wheat hosts. Additionally, based on genetic similarity between wheat blast and isolates infecting Urochloa species, it was proposed that the disease originally emerged via a host jump from this grass, and that Urochloa likely plays a central role in wheat blast epidemiology, owing to its widespread use as a pasture grass. However, due to inconsistencies with broader phylogenetic studies, we suspected that these seminal studies hadn't actually sampled the populations normally found on endemic grasses and, instead, had repeatedly isolated members of PoT and the related Lolium pathogen lineage (PoL1). Re-analysis of the Brazilian data as part of a comprehensive, global, phylogenomic dataset that included a small number of S. American isolates sampled away from wheat confirmed our suspicion and identified four new P. oryzae lineages on grass hosts. As a result, the conclusions underpinning current understanding in wheat blast's evolution, population biology and epidemiology are unsubstantiated and could be equivocal

Systemic risk and macroeconomic fat tails

We propose a mechanism for shock amplification that potentially can account for fat tails in the distribution of the growth rate of national output. We argue that extreme macroeconomic events, such as the Great Depression and the Great Recession, were preceded by significant turmoil in the banking system. We have developed a model of bank network formation and presented numerical simulations that show that, for the benchmark case, aggregate credit follows a random walk. When we introduce fire sales the model does not only produce larger variations in the growth of aggregate credit but also shows that there is an asymmetry between booms and busts that is also consistent with empirical evidence

Welfare effects of unbundling under different regulatory regimes in natural gas markets

In this paper, we develop a theoretical model that enriches the literature on the pros and cons of ownership unbundling vis-a`-vis lighter unbundling frameworks in the natural gas markets. For each regulatory framework, we compute equilibrium outcomes when an incumbent firm and a new entrant compete a` la Cournot in the final gas market. We find that the entrant’s contracting conditions in the upstream market and the transmission tariff are key determinants of the market structure in the downstream gas market (both with ownership and with legal unbundling). We also study how the regulator must optimally set transmission tariffs in each of the two unbundling regimes. We conclude that welfare maximizing tariffs often require free access to the transmission network (in both regulatoy regimes). However, when the regulator aims at promoting the break-even of the regulated transmission system operator, the first-best tariff is unfeasible in both regimes. Hence, we study a more realistic set-up, in which the regulator’s action is constrained by the break-even of the regulated firm (the transmission system operator). In this set-up, we find that, for a given transmission tariff, final prices in the downstream market are always higher with ownership unbundling than with legal unbundling.info:eu-repo/semantics/publishedVersio