Responses in carcass lean pH at 24 hours post-mortem in lines of Large White pigs selected for growth rate on a fixed ration over a set time

A restricted maximum likelihood analysis applied to an animal model showed no significant differences (P > 0.05) in pH value of the longissimus dorsi measured at 24 h post-mortem (pH24) between high and low lines of Large White pigs selected over 4 years for post-weaning growth rate on restricted feeding. Genetic and phenotypic correlations between pH24 and production and carcass traits were estimated using all performance testing records combined with the pH24 measurements (5.05–7.02) on slaughtered animals. The estimate of heritability for pH24 was moderate (0.29 ± 0.18). Genetic correlations between pH24 and production or carcass composition traits, except for ultrasonic backfat (UBF), were not significantly different from zero. UBF had a moderate, positive genetic correlation with pH24 (0.24 ± 0.33). These estimates of genetic correlations affirmed that selection for increased growth rate on restricted feeding is likely to result in limited changes in pH24 and pork quality since the selection does not put a high emphasis on reduced fatness.

Características bioquímicas da carne de bubalinos Mediterrâneo terminados em confinamento e abatidos em diferentes pesos

Este trabalho teve como objetivo avaliar as características bioquímicas da carne de bubalinos Mediterrâneo terminados em confinamento e abatidos em diferentes pesos. Foram utilizados 28 bubalinos Mediterrâneo jovens, com idade de 9 meses, e peso vivo médio inicial de 240kg. Os animais foram alimentados com ração total à vontade em regime de confinamento até atingirem pesos de abate de 450, 480, 510 e 540kg de peso vivo (tratamentos). Os valores de pH e temperatura dos músculos Longissimus dorsi e Bíceps femoris foram coletados a intervalos de duas horas durante 24 horas após o abate. Determinou-se a cor da carne pelos métodos subjetivo e objetivo. Não houve efeito de interação entre tratamento e tempo de coleta. Não houve diferença significativa entre os tratamentos em relação ao pH e à temperatura nos dois músculos estudados (Longissimus dorsi e Bíceps femoris) durante o processo de resfriamento das carcaças. Os valores médios de pH inicial e pH final dos músculos Longissimus dorsi e Bíceps femoris foram de 6,6 e 5,4; e de 6,3 e 5,5, respectivamente. Os valores médios de temperatura inicial e final dos músculos Longissimus dorsi e Bíceps femoris foram 39,7°C e 4,1°C; 40,4°C e 7,0°C, respectivamente. Quanto à cor da carne, pelo método subjetivo, não houve diferença significativa entre os tratamentos estudados, obtendo-se a média geral de 3,41 pontos. em relação à cor da carne pelo método objetivo, não houve diferença significativa entre os tratamentos estudados. Os valores médios encontrados foram : L*= 35,16; a*=12,43 e b*=5,29. A carne bubalina, apesar de se apresentar mais escura que a carne bovina, não traz prejuízos quanto ao aspecto visual para o consumidor.

Temperatura superficial de bovinos considerando áreas com e sem a presença de pelos.

Nos últimos anos um grande número de estudos utilizando a análise de imagens termográficas de animais na faixa do infravermelho vem sendo realizado. Além dos avanços tecnológicos que tornaram os sensores mais acessíveis, a preocupação com o bem estar e ambiência das instalações animais tem fomentado a utilização desse método não invasivo e de fácil execução. Neste trabalho foram utilizados 20 bovinos das raças Nelore e Pantaneiro. Após tricotomia de uma área sobre o músculo Longissimus dorsi próximo da 13ª costela, seguida de repouso por 24 horas, os animais foram avaliados por três dias consecutivos, seis vezes por dia. Foram aferidas as temperaturas em áreas com e sem pelos com uso de câmera termográfica. O experimento foi realizado em um Delineamento Inteiramente Casualizado (DIC), considerando o efeito de raça. As variáveis temperatura sem pelo (TSP) e a diferença de temperatura entre áreas com e sem pelo (DIF) não apresentaram efeito significativo para raça. Por outro lado, para a temperatura em áreas com pelos(TCP) o efeito de raça foi significativo, com os pantaneiros apresentando as maiores médias. Animais de ambas as raças encontravam-se em condições de conforto térmico durante o experimento. Os resultados mostram a necessidade de se olhar com cautela para trabalhos envolvendo imagens termográficas capturadas em superfícies recobertas por pelos em animais. Como as avaliações foram feitas na sombra e só houve diferença significativa entre áreas com pelos, é possível que as temperaturas registradas com termografia infra vermelha na superfície da pelagem dos animais representem, pelo menos em parte, características termofísicas dos pelos que as compõem (como a capacidade térmica, por exemplo), sendo tais temperaturas pouco representativas para a superfície do corpo dos indivíduos propriamente, como é comum se considerar.

Variation in myogenic differentiation 1 mRNA abundance is associated with beef tenderness in Nelore cattle.

The myogenic differentiation 1 gene (MYOD1) has a key role in skeletal muscle differentiation and composition through its regulation of the expression of several muscle-specific genes. We first used a general linear mixed model approach to evaluate the association of MYOD1 expression levels on individual beef tenderness phenotypes. MYOD1 mRNA levels measured by quantitative polymerase chain reactions in 136 Nelore steers were significantly associated (P ? 0.01) with Warner?Bratzler shear force, measured on the longissimus dorsi muscle after 7 and 14 days of beef aging. Transcript abundance for the muscle regulatory gene MYOD1 was lower in animals with more tender beef. We also performed a coexpression network analysis using whole transcriptome sequence data generated from 30 samples of longissimus muscle tissue to identify genes that are potentially regulated by MYOD1. The effect of MYOD1 gene expression on beef tenderness may emerge from its function as an activator of muscle-specific gene transcription such as for the serum response factor (C-fos serum response element-binding transcription factor) gene (SRF), which determines muscle tissue development, composition, growth and maturation.

Iron content affects lipogenic gene expression in the muscle of nelore beef cattle.

Iron (Fe) is an essential mineral for metabolism and plays a central role in a range of biochemical processes. Therefore, this study aimed to identify differentially expressed (DE) genes and metabolic pathways in Longissimus dorsi (LD) muscle from cattle with divergent iron content, as well as to investigate the likely role of these DE genes in biological processes underlying beef quality parameters. Samples for RNA extraction for sequencing and iron, copper, manganese, and zinc determination were collected from LD muscles at slaughter. Eight Nelore steers, with extreme genomic estimated breeding values for iron content (Fe-GEBV), were selected from a reference population of 373 animals. From the 49 annotated DE genes (FDR<0.05) found between the two groups, 18 were upregulated and 31 down-regulated for the animals in the low Fe-GEBV group. The functional enrichment analyses identified several biological processes, such as lipid transport and metabolism, and cell growth. Lipid metabolism was the main pathway observed in the analysis of metabolic and canonical signaling pathways for the genes identified as DE, including the genes FASN, FABP4, and THRSP, which are functional candidates for beef quality, suggesting reduced lipogenic activities with lower iron content. Our results indicate metabolic pathways that are partially influenced by iron, contributing to a better understanding of its participation in skeletal muscle physiology.

Qualitative-feed-restricted heavy swine: meat quality and morpho-histochemical characteristics of muscle fibers

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

Características qualitativas e quantitativas do músculo Longissimus de bubalinos e bovinos terminados em confinamento

Pós-graduação em Zootecnia - FCAV

Desempenho de bovinos cruzados terminados em confinamento e qualidade dos músculos longissimus e semitendinosus in natura e maturados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Valores nutricionais e qualitativos de carnes bovinas (Longissimus thoracis) provenientes de sistemas de produção orgânica e convencional

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Public acceptance of carbon dioxide capture and storage in a proposed demonstration area

With the rising levels of CO2 in the atmosphere, low-emission technologies with carbon dioxide capture and storage (CCS) provide one option for transforming the global energy infrastructure into a more environmentally, climate sustainable system. However, like many technology innovations, there is a social risk to the acceptance of CCS. This article presents the findings of an engagement process using facilitated workshops conducted in two communities in rural Queensland, Australia, where a demonstration project for IGCC with CCS has been announced. The findings demonstrate that workshop participants were concerned about climate change and wanted leadership from government and industry to address the issue. After the workshops, participants reported increased knowledge and more positive attitudes towards CCS, expressing support for the demonstration project to continue in their local area. The process developed is one that could be utilized around the world to successfully engage communities on the low carbon emission technology options.

Uncertainty budget in the measurement of typical airborne number, surface area and mass particle distributions

The effects of particulate matter on environment and public health have been widely studied in recent years. A number of studies in the medical field have tried to identify the specific effect on human health of particulate exposure, but agreement amongst these studies on the relative importance of the particles’ size and its origin with respect to health effects is still lacking. Nevertheless, air quality standards are moving, as the epidemiological attention, towards greater focus on the smaller particles. Current air quality standards only regulate the mass of particulate matter less than 10 μm in aerodynamic diameter (PM10) and less than 2.5 μm (PM2.5). The most reliable method used in measuring Total Suspended Particles (TSP), PM10, PM2.5 and PM1 is the gravimetric method since it directly measures PM concentration, guaranteeing an effective traceability to international standards. This technique however, neglects the possibility to correlate short term intra-day variations of atmospheric parameters that can influence ambient particle concentration and size distribution (emission strengths of particle sources, temperature, relative humidity, wind direction and speed and mixing height) as well as human activity patterns that may also vary over time periods considerably shorter than 24 hours. A continuous method to measure the number size distribution and total number concentration in the range 0.014 – 20 μm is the tandem system constituted by a Scanning Mobility Particle Sizer (SMPS) and an Aerodynamic Particle Sizer (APS). In this paper, an uncertainty budget model of the measurement of airborne particle number, surface area and mass size distributions is proposed and applied for several typical aerosol size distributions. The estimation of such an uncertainty budget presents several difficulties due to i) the complexity of the measurement chain, ii) the fact that SMPS and APS can properly guarantee the traceability to the International System of Measurements only in terms of number concentration. In fact, the surface area and mass concentration must be estimated on the basis of separately determined average density and particle morphology. Keywords: SMPS-APS tandem system, gravimetric reference method, uncertainty budget, ultrafine particles.

Intrusion detection techniques in wireless local area networks

This research investigates wireless intrusion detection techniques for detecting attacks on IEEE 802.11i Robust Secure Networks (RSNs). Despite using a variety of comprehensive preventative security measures, the RSNs remain vulnerable to a number of attacks. Failure of preventative measures to address all RSN vulnerabilities dictates the need for a comprehensive monitoring capability to detect all attacks on RSNs and also to proactively address potential security vulnerabilities by detecting security policy violations in the WLAN. This research proposes novel wireless intrusion detection techniques to address these monitoring requirements and also studies correlation of the generated alarms across wireless intrusion detection system (WIDS) sensors and the detection techniques themselves for greater reliability and robustness. The specific outcomes of this research are: A comprehensive review of the outstanding vulnerabilities and attacks in IEEE 802.11i RSNs. A comprehensive review of the wireless intrusion detection techniques currently available for detecting attacks on RSNs. Identification of the drawbacks and limitations of the currently available wireless intrusion detection techniques in detecting attacks on RSNs. Development of three novel wireless intrusion detection techniques for detecting RSN attacks and security policy violations in RSNs. Development of algorithms for each novel intrusion detection technique to correlate alarms across distributed sensors of a WIDS. Development of an algorithm for automatic attack scenario detection using cross detection technique correlation. Development of an algorithm to automatically assign priority to the detected attack scenario using cross detection technique correlation.