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Herein, we investigated the potential of REIMS analysis for classifying muscle composition and meat sensory quality. The study utilized 116 samples from 29 crossbred Angus × Salers, across three muscle types. Prediction models were developed combining REIMS fingerprints and meat quality metrics. Varying efficacy was observed across REIMS discriminations - muscle type (71 %), marbling level (32 %), untrained consumer evaluated tenderness (36 %), flavor liking (99 %) and juiciness (99 %). Notably, REIMS demonstrated the ability to classify 116 beef across four Meat Standards Australia grades with an overall accuracy of 37 %. Specifically, "premium" beef could be differentiated from "unsatisfactory", "good everyday" and "better than everyday" grades with accuracies of 99 %, 84 %, and 62 %, respectively. Limited efficacy was observed however, in classifying trained panel evaluated sensory quality and fatty acid composition. Additionally, key predictive features were tentatively identified from the REIMS fingerprints primarily comprised of molecular ions present in lipids, phospholipids, and amino acids.
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Paladar , Bovinos , Animais , Humanos , Espectrometria de Massas , Austrália , Ácidos Graxos/análise , Ácidos Graxos/química , Músculo Esquelético/química , Carne/análise , Aminoácidos/análise , Aminoácidos/químicaRESUMO
We consider the science, policy, and implementation (science-policy-society interface) issues around the agrifood system and the UK's transition to net zero. We conclude that agrifood policy should become more targeted, and the marriage of top-down and bottom-up approaches is key to co-create a pathway that is plausible for each stakeholder.
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Gastrointestinal nematode (GIN) parasites in grazing cattle are a major cause of production loss and their control is increasingly difficult due to anthelmintic resistance and climate change. Rotational grazing can support control and decrease reliance on chemical intervention, but is often complex due to the need to track grazing periods and infection levels, and the effect of weather on larval availability. In this paper, a simulation model was developed to predict the availability of infective larvae of the bovine GIN, Ostertagia ostertagi, at the level of individual pastures. The model was applied within a complex rotational grazing system and successfully reproduced observed variation in larval density between fields and over time. Four groups of cattle in their second grazing season (n = 44) were followed throughout the temperate grazing season with regular assessment of GIN faecal egg counts, which were dominated by O. ostertagi, animal weight and recording of field rotations. Each group of cattle was rotationally grazed on six group-specific fields throughout the 2019 grazing season. Maps and calendars were produced to illustrate the change in pasture infectivity (density of L3 on herbage) across the 24 separate grazing fields. Simulations predicted differences in pasture contamination levels in relation to the timing of grazing and the return period. A proportion of L3 was predicted to persist on herbage over winter, declining to similar intensities across fields before the start of the following grazing season, irrespective of contamination levels in the previous year. Model predictions showed good agreement with pasture larval counts. The model also simulated differences in seasonal pasture infectivity under rotational grazing in systems that differed in temperature and rainfall profiles. Further application could support individual farm decisions on evasive grazing and refugia management, and improved regional evaluation of optimal grazing strategies for parasite control. The integration of weather and livestock movement is inherent to the model, and facilitates consideration of climate change adaptation through improved disease control.
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Anti-Helmínticos , Doenças dos Bovinos , Helmintos , Enteropatias Parasitárias , Nematoides , Infecções por Nematoides , Bovinos , Animais , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/veterinária , Infecções por Nematoides/tratamento farmacológico , Fazendas , Contagem de Ovos de Parasitas/veterinária , Doenças dos Bovinos/parasitologia , Enteropatias Parasitárias/veterinária , Anti-Helmínticos/uso terapêuticoRESUMO
Meat products are particularly plagued by safety problems because of their complicated structure, various production processes and complex supply chains. Rapid and non-invasive analytical methods to evaluate meat quality have become a priority for the industry over the conventional chemical methods. To achieve rapid analysis of safety and quality parameters of meat products, hyperspectral imaging (HSI) is now widely applied in research studies for detecting the various components of different meat products, but its application in meat production and supply chain integrity as a quality control (QC) solution is still ambiguous. This review presents the fresh look at the current states of HSI research as both the scope and the applicability of the HSI in the meat quality evaluation expanded. The future application scenarios of HSI in the supply chain and the future development of HSI hardware and software are also discussed, by which HSI technology has the potential to enable large scale meat product testing. With a fully adapted for factory setting HSI, the inspection coverage can reliably identify the chemical properties of meat products. With the introduction of Food Industry 4.0, HSI advances can change the meat industry to become from reactive to predictive when facing meat safety issues.
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Increasing demands are being placed on meat producers to verify more about their product with regards to safety, quality and authenticity. There are many methods that can detect aspects of these parameters in meat, yet most are too slow to keep up with the demands of modern meat processing plants and supply chains. A new technology, Rapid Evaporative Ionisation Mass Spectrometry (REIMS), has the potential to bridge the gap between advanced laboratory measurements and technology that can screen for quality, safety and authenticity parameters in a single measurement. Analysis with REIMS generates a detailed mass spectral fingerprint representative of a meat sample without the need for sample processing. REIMS has successfully been used to detect species fraud, detect use of hormones in meat animals, monitor meat processing and to detect off flavours such as boar taint. The aim of this review is to summarize these and other applications to highlight the potential of REIMS for meat analysis. Sampling methods and important considerations for data analysis are discussed as well as limitations of the technology and remaining challenges for practical adoption.
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Espectrometria de Massas/métodos , Carne/análise , Animais , Fraude , Espectrometria de Massas/instrumentação , Carne/normasRESUMO
There is little modern data addressing the differential lifetime growth of commercially reared low and average birthweight pigs born into large litters (>14 piglets). As such, the main aim of this study was to quantify the lifetime growth and mortality rate of low and average birthweight pigs on commercial farms in Northern Ireland. It was also aimed to analyze the level, stage and cause of mortality within each birthweight category. A total of 328 low birthweight (low BW; <1 kg) and 292 average birthweight (Av BW; 1.3 to 1.7 kg) pigs were individually identified across four commercial farms and one research farm. Animal growth and mortality were monitored on an individual basis from birth until slaughter age. Av BW pigs were heavier than low BW pigs throughout the trial (P < 0.001), with a weight advantage of 1.16 kg at weaning increasing to over 9 kg at slaughter age. Av BW pigs recorded a superior average daily gain (ADG) to low BW pigs throughout the trial (P < 0.05), with the greatest difference recorded immediately postweaning between weeks 4 and 8 and weeks 8 and 12 when a 77 and 85 g/d difference was recorded, respectively. AV BW pigs which were cross-fostered were significantly lighter than those remaining with their birth mother at weaning (0.9 kg), week 8 (1.7 kg), and week 12 (3.1 kg) (P < 0.05, respectively). The variance of weight was significantly greater for the AV BW pig population than the low BW pig population at week 4 (P < 0.001) and 8 (P < 0.05). Preweaning mortality of low BW pigs was over three times greater than that of Av BW pigs (21% vs. 6%; P < 0.001), with low BW deaths occurring earlier (9.2 d vs. 15.4 d; P < 0.001) and at a lighter weight (1.2 vs. 2.4 kg; P < 0.001) than Av BW pigs. There was a clear association between birthweight and cause of preweaning death (P < 0.05), with starvation (49%) and overlying (28%) accounting for the majority of low BW mortalities. Birthweight had no effect on rate, age, or weight of postweaning mortalities (P > 0.05). The alimentary tract (27%) and respiratory tract (27%) were the most commonly implicated body systems following postmortem examination of postweaning deaths. In conclusion, this study quantified the inferior weight, growth rate, and mortality of low BW pigs, identifying the lactation and immediate postweaning periods as having the greatest potential in reducing this birthweight associated growth differential.
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Improved genetics in commercial pig production have resulted in larger litter sizes. However this has increased the prevalence of compromised pigs exhibiting inferior birthweights, weaning weights, and lifetime performance. This study aimed to determine the effects of increased sow lactation feed intake on growth of low and average birthweight piglets until 10 wk of age. Low (Low BW; <1 kg) and average (Av BW; 1.3-1.7 kg) birthweight animals were reared in uniformly weighted litters comprising 14 piglets on a foster mother offered either a low (Low FA; max 7.5 kg/d) or high (High FA; max 11 kg/d) feed allowance over a 28- ± 1-d lactation. Piglet performance was monitored from birth until 10 wk of age. Sows offered a High FA consumed 42.4 kg more feed on average than those offered Low FA, resulting in a greater derived milk yield (P < 0.05). Animals of Av BW remained heavier than Low BW pigs throughout the trial (P < 0.05). Piglets reared by High FA sows were heavier at weeks 3, 4, 5, and 7 (P < 0.05) but not week 10 (P > 0.05). Growth rate of piglets relative to their birthweight was significantly greater for Low BW piglets than those of Av BW during lactation (P < 0.001). Piglets reared by sows offered a High FA expressed greater relative growth preweaning (P < 0.05); however, postweaning relative growth for piglets reared on sows offered a Low FA was greater (P < 0.05) suggesting compensatory growth. Neither birthweight nor sow feed allowance significantly affected preweaning mortality (P > 0.05). However, Low BW animals on sows with a High FA recorded half the preweaning mortality of Low BW pigs on sows with a Low FA. During week 1 of lactation, Av BW litters recorded a greater total suckling duration compared to Low BW litters (P < 0.05) but there was no difference in suckling frequency (P > 0.05). During week 3 of lactation, High FA litters displayed a significantly lower suckling frequency (P < 0.05) yet a greater total suckling duration (P < 0.001). Average daily gain was greater for Av BW pigs during weeks 4-7 (P < 0.001) but no difference was recorded between weeks 7 and 10 (P > 0.05). Average daily feed intake was greater for Av BW pigs throughout the nursery period (P < 0.05) but feed-conversion ratio did not differ compared to Low BW pens (P>0.05). In conclusion, offering sows a High FA increased weaning weight of all animals; however, birthweight was the major determinant of postweaning performance.
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OBJECTIVE: The 3×3 factorial arrangement was used to investigate if either high watersoluble carbohydrates (WSC) cultivars or suitable time of day that the grass cut could improve nutrient values and in vitro fermentation characteristics. METHODS: The 3 cultivars were mowed at 3 diurnal time points and included a benchmark WSC ryegrass cultivar 'Premium', and 2 high WSC cultivars AberAvon and AberMagic, which contained, on average, 157, 173, and 193 g/kg dry matter (DM) of WSC, and 36.0, 36.5, and 34.1 g/kg DM of N during 7th regrowth stage, respectively. The fermentation jars were run at 39°C with gas production recorded and sampled at 2, 5, 8, 11, 14, 17, 22, 28, 36, and 48 h. The rumen liquid was collected from 3 rumen fistulated cows grazing on ryegrass pasture. RESULTS: High WSC cultivars had significantly greater WSC content, in vitro DM digestibility (IVDMD) and total gas production (TGP), and lower lag time than Premium cultivar. Methane production for AberMagic cultivar containing lower N concentration was marginally lower than that for AberAvon and Premium cultivars. Grass cut at Noon or PM contained greater WSC concentration, IVDMD and TGP, and lower N and neutral detergent fiber (NDF) contents, but CH4 production was also increased, compared to grass cut in AM. Meanwhile, the effects of diurnal cutting time were influenced by cultivars, such as in vitro CH4 production for AberMagic was not affected by cutting time. The IVDMD and gas production per unit of DM incubated were positively related to WSC concentration, WSC/N and WSC/NDF, respectively, and negatively related to N and NDF concentrations. CONCLUSION: These results imply either grass cut in Noon or PM or high WSC cultivars could improve nutrient values, IVDMD and in vitro TGP, and that AberMagic cultivar has a slightly lower CH4 production compared to AberAvon and Premium. Further study is necessary to determine whether the increase of CH4 production response incurred by shifting from AM cutting to Noon and/or PM cutting could be compensated for by high daily gain from increased WSC concentration and DM digestibility.
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The rumen is a complex ecosystem composed of anaerobic bacteria, protozoa, fungi, methanogenic archaea and phages. These microbes interact closely to breakdown plant material that cannot be digested by humans, whilst providing metabolic energy to the host and, in the case of archaea, producing methane. Consequently, ruminants produce meat and milk, which are rich in high-quality protein, vitamins and minerals, and therefore contribute to food security. As the world population is predicted to reach approximately 9.7 billion by 2050, an increase in ruminant production to satisfy global protein demand is necessary, despite limited land availability, and whilst ensuring environmental impact is minimized. Although challenging, these goals can be met, but depend on our understanding of the rumen microbiome. Attempts to manipulate the rumen microbiome to benefit global agricultural challenges have been ongoing for decades with limited success, mostly due to the lack of a detailed understanding of this microbiome and our limited ability to culture most of these microbes outside the rumen. The potential to manipulate the rumen microbiome and meet global livestock challenges through animal breeding and introduction of dietary interventions during early life have recently emerged as promising new technologies. Our inability to phenotype ruminants in a high-throughput manner has also hampered progress, although the recent increase in "omic" data may allow further development of mathematical models and rumen microbial gene biomarkers as proxies. Advances in computational tools, high-throughput sequencing technologies and cultivation-independent "omics" approaches continue to revolutionize our understanding of the rumen microbiome. This will ultimately provide the knowledge framework needed to solve current and future ruminant livestock challenges.
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The nutritional value of meat is an increasingly important factor influencing consumer preferences for poultry, red meat and processed meat products. Intramuscular fat content and composition, in addition to high quality protein, trace minerals and vitamins are important determinants of nutritional value. Fat content of meat at retail has decreased substantially over the past 40 years through advances in animal genetics, nutrition and management and changes in processing techniques. Evidence of the association between diet and the incidence of human non-communicable diseases has driven an interest in developing production systems for lowering total SFA and trans fatty acid (TFA) content and enrichment of n-3 PUFA concentrations in meat and meat products. Typically, poultry and pork has a lower fat content, containing higher PUFA and lower TFA concentrations than lamb or beef. Animal genetics, nutrition and maturity, coupled with their rumen microbiome, are the main factors influencing tissue lipid content and relative proportions of SFA, MUFA and PUFA. Altering the fatty acid (FA) profile of lamb and beef is determined to a large extent by extensive plant and microbial lipolysis and subsequent microbial biohydrogenation of dietary lipid in the rumen, and one of the major reasons explaining the differences in lipid composition of meat from monogastrics and ruminants. Nutritional strategies can be used to align the fat content and FA composition of poultry, pork, lamb and beef with Public Health Guidelines for lowering the social and economic burden of chronic disease.
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Gorduras na Dieta/análise , Ácidos Graxos/análise , Manipulação de Alimentos/métodos , Carne/análise , Valor Nutritivo , Animais , Bovinos , Humanos , Lipólise , Aves Domésticas , Ovinos , SuínosRESUMO
There is considerable interest in enhancing beneficial fatty acids, particularly 18:3n-3, conjugated linoleic acid and long chain n-3 fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in beef to provide benefits to human health. Here, the potential to enhance these fatty acids by feeding a n-3 polyunsaturated fatty acid (PUFA)-rich plant extract (PX) from lucerne is presented. Cattle (n=8/diet) were assigned to the following finishing diets: straw and concentrate (S-CC); straw and concentrate containing 25% PX and 2000IUvitaminE/kg PX-concentrate (S-PXC); grass silage (GS); GS plus 75gPX/kg dry matter intake (DMI) (GS-LPX) or GS plus 150g PX/kg DMI (GS-HPX). Addition of PX to concentrates or GS increased the n-3 fatty acid content of loin muscle and had favourable effects on the n-6:n-3 PUFA ratio (P<0.05), without detrimental effects on loin muscle sensory characteristics.
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Ração Animal/análise , Ácidos Graxos/análise , Medicago sativa , Carne Vermelha/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos , Dieta/veterinária , Humanos , Masculino , Músculo Esquelético/química , Extratos Vegetais , SilagemRESUMO
Eating quality of the same meat samples from different animal types cooked at two end-point cooking temperatures (55°C and 74°C) was evaluated by trained panels in France and the United Kingdom. Tenderness and juiciness scores were greater at 55°C than at 74°C, irrespective of the animal type and location of the panel. The UK panel, independently of animal type, gave greater scores for beef flavour (+7 to +24%, P<0.001) but lower scores for abnormal flavour (-10 to -17%, P<0.001) at 74°C. Abnormal flavour score by the French panel was higher at 74°C than at 55°C (+26%, P<0.001). Irrespective of the data set, tenderness was correlated with juiciness and beef flavour. Overall, this study found that cooking beef at a lower temperature increased tenderness and juiciness, irrespective of the location of the panel. In contrast, cooking beef at higher temperatures increased beef flavour and decreased abnormal flavour for the UK panelists but increased abnormal flavour for the French panel.
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Culinária/métodos , Carne Vermelha/análise , Animais , Bovinos , Feminino , Manipulação de Alimentos , Preferências Alimentares , França , Humanos , Masculino , Sensação , Paladar , Temperatura , Reino UnidoRESUMO
Grassland-based ruminant production systems are integral to sustainable food production in Europe, converting plant materials indigestible to humans into nutritious food, while providing a range of environmental and cultural benefits. Climate change poses significant challenges for such systems, their productivity and the wider benefits they supply. In this context, grassland models have an important role in predicting and understanding the impacts of climate change on grassland systems, and assessing the efficacy of potential adaptation and mitigation strategies. In order to identify the key challenges for European grassland modelling under climate change, modellers and researchers from across Europe were consulted via workshop and questionnaire. Participants identified fifteen challenges and considered the current state of modelling and priorities for future research in relation to each. A review of literature was undertaken to corroborate and enrich the information provided during the horizon scanning activities. Challenges were in four categories relating to: 1) the direct and indirect effects of climate change on the sward 2) climate change effects on grassland systems outputs 3) mediation of climate change impacts by site, system and management and 4) cross-cutting methodological issues. While research priorities differed between challenges, an underlying theme was the need for accessible, shared inventories of models, approaches and data, as a resource for stakeholders and to stimulate new research. Developing grassland models to effectively support efforts to tackle climate change impacts, while increasing productivity and enhancing ecosystem services, will require engagement with stakeholders and policy-makers, as well as modellers and experimental researchers across many disciplines. The challenges and priorities identified are intended to be a resource 1) for grassland modellers and experimental researchers, to stimulate the development of new research directions and collaborative opportunities, and 2) for policy-makers involved in shaping the research agenda for European grassland modelling under climate change.
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Improving the health beneficial fatty acid content of meat and milk is a major challenge requiring an increased understanding of rumen lipid metabolism. In this study, we isolated and characterized rumen bacterial lipases/esterases using functional metagenomics. Metagenomic libraries were constructed from DNA extracted from strained rumen fluid (SRF), solid-attached bacteria (SAB) and liquid-associated rumen bacteria (LAB), ligated into a fosmid vector and subsequently transformed into an Escherichia coli host. Fosmid libraries consisted of 7,744; 8,448; and 7,680 clones with an average insert size of 30 to 35 kbp for SRF, SAB and LAB, respectively. Transformants were screened on spirit blue agar plates containing tributyrin for lipase/esterase activity. Five SAB and four LAB clones exhibited lipolytic activity, and no positive clones were found in the SRF library. Fosmids from positive clones were pyrosequenced and twelve putative lipase/esterase genes and two phospholipase genes retrieved. Although the derived proteins clustered into diverse esterase and lipase families, a degree of novelty was seen, with homology ranging from 40 to 78% following BlastP searches. Isolated lipases/esterases exhibited activity against mostly short- to medium-chain substrates across a range of temperatures and pH. The function of these novel enzymes recovered in ruminal metabolism needs further investigation, alongside their potential industrial uses.
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Esterases/genética , Esterases/metabolismo , Metagenoma , Rúmen/microbiologia , Animais , Bovinos , Escherichia coli/genética , Esterases/isolamento & purificação , Expressão Gênica , Concentração de Íons de Hidrogênio , Hidrólise , Dados de Sequência Molecular , Análise de Sequência de DNA , Temperatura , Transformação Bacteriana , Triglicerídeos/metabolismoRESUMO
Developing novel strategies for improving the fatty acid composition of ruminant products relies upon increasing our understanding of rumen bacterial lipid metabolism. This study investigated whether flax or echium oil supplementation of steer diets could alter the rumen fatty acids and change the microbiome. Six Hereford × Friesian steers were offered grass silage/sugar beet pulp only (GS), or GS supplemented either with flax oil (GSF) or echium oil (GSE) at 3% kg(-1) silage dry matter in a 3 × 3 replicated Latin square design with 21-day periods with rumen samples taken on day 21 for the analyses of the fatty acids and microbiome. Flax oil supplementation of steer diets increased the intake of polyunsaturated fatty acids, but a substantial degree of rumen biohydrogenation was seen. Likewise, echium oil supplementation of steer diets resulted in increased intake of 18:4n-3, but this was substantially biohydrogenated within the rumen. Microbiome pyrosequences showed that 50% of the bacterial genera were core to all diets (found at least once under each dietary intervention), with 19.10%, 5.460% and 12.02% being unique to the rumen microbiota of steers fed GS, GSF and GSE respectively. Higher 16S rDNA sequence abundance of the genera Butyrivibrio, Howardella, Oribacterium, Pseudobutyrivibrio and Roseburia was seen post flax feeding. Higher 16S rDNA abundance of the genus Succinovibrio and Roseburia was seen post echium feeding. The role of these bacteria in biohydrogenation now requires further study.
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Biota , Dieta/métodos , Ácidos Graxos/análise , Óleos de Plantas/administração & dosagem , Rúmen/química , Rúmen/microbiologia , Animais , Bovinos , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Echium/química , Linho/química , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Secoisolariciresinol diglucoside (SDG), the most abundant lignan in flaxseed, is metabolized by the ruminal microbiota into enterolignans, which are strong antioxidants. Enterolactone (EL), the main mammalian enterolignan produced in the rumen, is transferred into physiological fluids, with potentially human health benefits with respect to menopausal symptoms, hormone-dependent cancers, cardiovascular diseases, osteoporosis and diabetes. However, no information exists to our knowledge on bacterial taxa that play a role in converting plant lignans into EL in ruminants. In order to investigate this, eight rumen cannulated cows were used in a double 4 × 4 Latin square design and fed with four treatments: control with no flax meal (FM), or 5%, 10% and 15% FM (on a dry matter basis). Concentration of EL in the rumen increased linearly with increasing FM inclusion. Total rumen bacterial 16S rRNA concentration obtained using Q-PCR did not differ among treatments. PCR-T-RFLP based dendrograms revealed no global clustering based on diet indicating between animal variation. PCR-DGGE showed a clustering by diet effect within four cows that had similar basal ruminal microbiota. DNA extracted from bands present following feeding 15% FM and absent with no FM supplementation were sequenced and it showed that many genera, in particular Prevotella spp., contributed to the metabolism of lignans. A subsequent in vitro study using selected pure cultures of ruminal bacteria incubated with SDG indicated that 11 ruminal bacteria were able to convert SDG into secoisolariciresinol (SECO), with Prevotella spp. being the main converters. These data suggest that Prevotella spp. is one genus playing an important role in the conversion of plant lignans to human health beneficial antioxidants in the rumen.
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Antioxidantes/metabolismo , Lignanas/metabolismo , Prevotella , RNA Ribossômico 16S/genética , Estômago de Ruminante/microbiologia , Animais , Bovinos , Feminino , Humanos , Polimorfismo de Fragmento de Restrição , Prevotella/genética , Prevotella/isolamento & purificação , Prevotella/metabolismo , Reação em Cadeia da Polimerase em Tempo RealRESUMO
This paper focuses on dietary approaches to control intramuscular fat deposition to increase beneficial omega-3 polyunsaturated fatty acids (PUFA) and conjugated linoleic acid content and reduce saturated fatty acids in beef. Beef lipid trans-fatty acids are considered, along with relationships between lipids in beef and colour shelf-life and sensory attributes. Ruminal lipolysis and biohydrogenation limit the ability to improve beef lipids. Feeding omega-3 rich forage increases linolenic acid and long-chain PUFA in beef lipids, an effect increased by ruminally-protecting lipids, but consequently may alter flavour characteristics and shelf-life. Antioxidants, particularly α-tocopherol, stabilise high concentrations of muscle PUFA. Currently, the concentration of long-chain omega-3 PUFA in beef from cattle fed non-ruminally-protected lipids falls below the limit considered by some authorities to be labelled a source of omega-3 PUFA. The mechanisms regulating fatty acid isomer distribution in bovine tissues remain unclear. Further enhancement of beef lipids requires greater understanding of ruminal biohydrogenation.
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Ração Animal , Dieta , Gorduras na Dieta , Ácidos Graxos Ômega-3 , Carne/análise , Valor Nutritivo , Animais , Bovinos , Gorduras na Dieta/metabolismo , Gorduras na Dieta/farmacologia , Suplementos Nutricionais , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-3/farmacologia , Humanos , Carne/normas , RúmenRESUMO
An experiment investigated whether the inclusion of chicory (Cichorium intybus) in swards grazed by beef steers altered their performance, carcass characteristics or parasitism when compared to steers grazing perennial ryegrass (Lolium perenne). Triplicate 2-ha plots were established with a chicory/ryegrass mix or ryegrass control. Forty-eight Belgian Blue-cross steers were used in the first grazing season and a core group (n = 36) were retained for finishing in the second grazing season. The experiment comprised of a standardisation and measurement period. During standardisation, steers grazed a ryegrass/white clover pasture as one group. Animals were allocated to treatment on the basis of liveweight, body condition and faecal egg counts (FEC) determined 7 days prior to the measurement period. The measurement period ran from 25 May until 28 September 2010 and 12 April until 11 October 2011 in the first and second grazing year. Steers were weighed every 14 days at pasture or 28 days during housing. In the first grazing year, faecal samples were collected for FEC and parasite cultures. At the end of the first grazing year, individual blood samples were taken to determine O. ostertagi antibody and plasma pepsinogen levels. During winter, animals were housed as one group and fed silage. In the second grazing year, steers were slaughtered when deemed to reach fat class 3. Data on steer performance showed no differences in daily live-weight gain which averaged 1.04 kg/day. The conformation, fat grade and killing out proportion of beef steers grazing chicory/ryegrass or ryegrass were not found to differ. No differences in FEC, O. ostertagi antibody or plasma pepsinogen levels of beef steers grazing either chicory/ryegrass or ryegrass were observed. Overall, there were no detrimental effects of including chicory in swards grazed by beef cattle on their performance, carcass characteristics or helminth parasitism, when compared with steers grazing ryegrass.
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Lolium , Ração Animal , Criação de Animais Domésticos , Animais , Bovinos , Cichorium intybus , Carne , Contagem de Ovos de Parasitas , Aumento de PesoRESUMO
Despite efforts by the industry to control the eating quality of beef, there remains a high level of variability in palatability, which is one reason for consumer dissatisfaction. In Europe, there is still no reliable on-line tool to predict beef quality and deliver consistent quality beef to consumers. Beef quality traits depend in part on the physical and chemical properties of the muscles. The determination of these properties (known as muscle profiling) will allow for more informed decisions to be made in the selection of individual muscles for the production of value-added products. Therefore, scientists and professional partners of the ProSafeBeef project have brought together all the data they have accumulated over 20 years. The resulting BIF-Beef (Integrated and Functional Biology of Beef) data warehouse contains available data of animal growth, carcass composition, muscle tissue characteristics and beef quality traits. This database is useful to determine the most important muscle characteristics associated with a high tenderness, a high flavour or generally a high quality. Another more consumer driven modelling tool was developed in Australia: the Meat Standards Australia (MSA) grading scheme that predicts beef quality for each individual muscle×specific cooking method combination using various information on the corresponding animals and post-slaughter processing factors. This system has also the potential to detect variability in quality within muscles. The MSA system proved to be effective in predicting beef palatability not only in Australia but also in many other countries. The results of the work conducted in Europe within the ProSafeBeef project indicate that it would be possible to manage a grading system in Europe similar to the MSA system. The combination of the different modelling approaches (namely muscle biochemistry and a MSA-like meat grading system adapted to the European market) is a promising area of research to improve the prediction of beef quality. In both approaches, the volume of data available not only provides statistically sound correlations between various factors and beef quality traits but also a better understanding of the variability of beef quality according to various criteria (breed, age, sex, pH, marbling etc.).
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Carne/análise , Estresse Mecânico , Paladar , Animais , Austrália , Bovinos , Europa (Continente) , Humanos , Carne/normas , Modelos Biológicos , Músculos , Controle de QualidadeRESUMO
Following the isolation, cultivation and characterization of the rumen bacterium Anaerovibrio lipolyticus in the 1960s, it has been recognized as one of the major species involved in lipid hydrolysis in ruminant animals. However, there has been limited characterization of the lipases from the bacterium, despite the importance of understanding lipolysis and its impact on subsequent biohydrogenation of polyunsaturated fatty acids by rumen microbes. This study describes the draft genome of Anaerovibrio lipolytica 5ST, and the characterization of three lipolytic genes and their translated protein. The uncompleted draft genome was 2.83 Mbp and comprised of 2,673 coding sequences with a G+C content of 43.3%. Three putative lipase genes, alipA, alipB and alipC, encoding 492-, 438- and 248- amino acid peptides respectively, were identified using RAST. Phylogenetic analysis indicated that alipA and alipB clustered with the GDSL/SGNH family II, and alipC clustered with lipolytic enzymes from family V. Subsequent expression and purification of the enzymes showed that they were thermally unstable and had higher activities at neutral to alkaline pH. Substrate specificity assays indicated that the enzymes had higher hydrolytic activity against caprylate (C8), laurate (C12) and myristate (C14).