Effects of l-carnitine supplementation to suckling piglets on carcass and meat quality at market age

In a previous study, carnitine supplementation to piglets during the suckling period resulted in an increased total muscle fibre number at weaning in piglets of low birth weight. The objective of the present study was to investigate whether this effect is maintained until market age and whether this would attenuate the negative consequences of low birth weight on carcass and meat quality. Using a split-plot design with litter as block, sex as whole plot and treatment as subplot, the effects of early-postnatal l-carnitine supplementation on female and castrated male piglets of low birth weight were investigated on a total of 56 German Landrace piglets from 14 litters. From days 7 to 27 of age piglets were orally supplemented once daily with 400 mg of l-carnitine dissolved in 1 ml of water or received an equal volume of water without carnitine. From weaning (day 28) until slaughter (day 166 of age) all pigs were fed standard diets. At weaning, carnitine-supplemented piglets had a twofold increased concentration of free carnitine (P < 0.001) and a lower concentration of non-esterified fatty acids (P < 0.05) in blood plasma indicating that carnitine became bioavailable and increased fatty acid utilization during the period of supplementation. Growth performance was not influenced by treatment in any growth period. Dual-energy X-ray absorptiometry revealed no differences in body composition between groups in weeks 12, 16 and 20 of age. LW at slaughter, carcass weight, measures of meat yield and fat accretion, as well as body composition by chemical analyses and dissection of primal cuts did not differ between treatments. No differences between control and carnitine-treated pigs in total fibre number (P = 0.85) and fibre cross-sectional area (P = 0.68) in m. semitendinosus (ST) measured at slaughter could be observed. The carnitine group tended to exhibit a smaller proportion of slow-twitch oxidative fibres (P = 0.08), a greater proportion of fast-twitch glycolytic fibres (P = 0.11), and increased specific lactate dehydrogenase activity (P = 0.09) in ST indicating a more glycolytic muscle metabolism. Compared with the controls, a lower pH₂₄ value was observed (P = 0.05) in ST muscle of carnitine-supplemented pigs, which – in castrates only – was associated with an increased drip loss (P < 0.01). Meat quality traits in m. longissimus were not influenced by treatment. In conclusion, our hypothesis that early-postnatal carnitine supplementation to piglets of low birth weight permanently increases myofibre number and improves later carcass and meat quality could not be confirmed by this experiment.     

Reliability of map accuracy assessments: A reply to Roff et al. (2016)

Roff et al. (Ecological Management and Restoration, 17 , 2016, 000) provide a discussion of the criteria expected for the best approach to validation of mapping programs and uses Hunter (Ecological Management & Restoration 17 , 2016, 40) to highlight issues involved. While we support the general principles outlined, we note that the review does not apply the same standards to Sivertsen et al. (Greater Hunter Native Vegetation Mapping Geodatabase Guide (Version 4.0). Office of Environment and Heritage, Department of the Premier and Cabinet, Sydney, Australia, 2011), the original document critiqued by Hunter (Ecological Management & Restoration 17 , 2016, 40). The Hunter (Ecological Management & Restoration 17 , 2016, 40) validation was based on a larger sample size, greater sampling within mapping units and greater representation of landscapes than Sivertsen et al. (Greater Hunter Native Vegetation Mapping Geodatabase Guide (Version 4.0). Office of Environment and Heritage, Department of the Premier and Cabinet, Sydney, Australia, 2011). Survey and validation sites being placed along public roads and lands are common to both the general Office of Environment and Heritage (OEH) and Hunter (Ecological Management & Restoration 17 , 2016, 40) validation methodologies. Thus, the criticisms of Roff et al. (Ecological Management and Restoration, 17 , 2016, 000) of the Hunter (Ecological Management & Restoration 17 , 2016, 40) approach apply equally, if not more, to Sivertsen et al. (Greater Hunter Native Vegetation Mapping Geodatabase Guide (Version 4.0). Office of Environment and Heritage, Department of the Premier and Cabinet, Sydney, Australia, 2011). We outline in the article how the Roff et al. (Ecological Management and Restoration, 17 , 2016, 000) critique was selective and in some cases incorrect in its analysis of issues presented in Hunter (Ecological Management & Restoration 17 , 2016, 40) and did not apply the same criteria to their own work. We conclude by discussing future directions for validating and mapping vegetation communities.     

Interannual variability,stability and resilience in UK plant communities

Plant communities are often assumed to be stable on a year-to-year basis. We present evidence that species composition in permanent quadrats changes considerably between years at a range of Environmental Change Network sites across the UK. The extent of this variability varies with habitat type. Communities associated with low disturbance levels and low agricultural inputs, particularly moorland (upland grass and heath) and bog communities, are most stable.Inter-annual variability should, therefore, be considered in designing monitoring schemes to ensure that frequency of recording is sufficient to avoid short-term fluctuations obscuring long-term trends.More diverse communities were more stable, with less species turnover between years. However, diverse communities also tended to be dominated by slow-growing, slow-reproducing plants, adapted to low nutrient conditions, identified as ‘stress tolerators’ in the Grime CSR scheme and low Ellenberg N values. Species compositional stability was more strongly correlated with these indices of plant functional types than species richness. Nevertheless, a significant effect of species richness could be identified, even after other causes of variation were accounted for.More stable communities in our study are likely to be resilient to low levels of environmental change, although they may still change, and possibly change dramatically if critical ‘tipping points’ are reached.     

AURITA: an affordable,autonomous recording device for acoustic monitoring of audible and ultrasonic frequencies

Passive acoustic monitoring can be used for many purposes including biodiversity and habitat assessments and studying the ecology of populations, communities and soundscapes. As such, acoustic recording devices are essential data collection tools for bioacousticians and soundscape ecologists. Currently available commercial options are typically expensive and limited to recording either ultrasonic or audible frequencies. Here, we present the AURITA (Audible and Ultrasonic Recording In TAndem) for the autonomous collection of both audible and ultrasonic acoustic data. This self-contained, modular unit combines the Solo, an open-source, Raspberry-Pi-based recorder and a commercially available bat recorder, the Peersonic RPA2, enabling it to capture sounds from 60 Hz to 192 kHz in WAV format. The configuration presented costs ~£350 (excluding memory cards and batteries) to produce and can be maintained and repaired in the field. Two nine-week field tests involving 12 AURITA units were conducted in 2016 and 2017 and confirmed their reliability, resulting in 34,093 h of audible data and 551 h of ultrasonic data; all units were retrieved successfully and intact. The AURITA proved to be reliable in the field and produced high-quality acoustic data, making it ideal for simultaneous monitoring in both audible and ultrasonic frequencies over continuous periods of time.     

Estimation of Respiratory Nasal Pressure and Flow Rate Signals Using Different Respiratory Sound Features

BackgroundRespiratory sounds are associated with the flow rate, nasal flow pressure, and physical characteristics of airways. In this study, we aimed to develop the flow rate and nasal flow pressure estimation models for the clinical application, and find out the optimal feature set for estimation to achieve the optimal model performance.MethodsRespiratory sounds and flow rate were acquired from nine healthy volunteers. Respiratory sounds and nasal flow pressure were acquired from twenty-three healthy volunteers. Four types of respiratory sound features were extracted for flow rate and nasal flow pressure estimation using different estimation models. Effects of estimations using these features were evaluated using Bland-Altman analysis, estimation error, and respiratory sound feature calculation time. Besides, expiratory and inspiratory phases divided estimation errors were compared with united estimation errors.ResultsThe personalized logarithm model was selected as the optimal flow rate estimation model. Respiratory nasal flow pressure estimation based on this model was also performed. For the four different respiratory sound features, there is no statistically significant difference in flow rate and pressure estimation errors. LogEnvelope was, therefore, chosen as the optimal feature because of the lowest computational cost. In addition, for any type of respiratory sound feature, no statistically significant difference was observed between divided and united estimation errors (flow rate and pressure).ConclusionRespiratory flow rate and nasal flow pressure can be estimated accurately using respiratory sound features. Expiratory and inspiratory phases united estimation using respiratory sounds is a more reasonable estimation method than divided estimation. LogEnvelope can be used for this united respiratory flow rate and nasal flow pressure estimation with minimum computational cost and acceptable estimation error.     

Differential expression of sarcoplasmic proteins in four heterogeneous ovine skeletal muscles

Fiber-type distribution is known to vary widely within and between muscles according to differences in muscle functions. 2-DE and MALDI-MS were used to investigate the molecular basis of muscle fiber type-related variability. We compared four lamb skeletal muscles with heterogeneous fiber-type composition that are relatively rich in fast-twitch fiber types, i.e., the semimembranosus, vastus medialis, longissimus dorsi, and tensor fasciae latae (TL). Our results clearly showed that none of the glycolytic metabolism enzymes detected, including TL which was most strongly glycolytic, made intermuscular differentiation possible. Muscle differentiation was based on the differential expression of proteins involved in oxidative metabolism, including not only citric acid cycle enzymes but also other classes of proteins with functions related to oxidative metabolism, oxidative stress, and probably to higher protein turnover. Detected proteins were involved in transport (carbonate dehydratase, myoglobin, fatty acid-binding protein), repair of misfolding damage (heat shock protein (HSP) 60 kDa, HSP-27 kDa, alpha-crystallin beta subunit, DJ1, stress-induced phosphoprotein), detoxification or degradation of impaired proteins (GST-Pi, aldehyde dehydrogenase, peroxiredoxin, ubiquitin), and protein synthesis (tRNA-synthetase). The fractionating method led to the detection of proteins involved in different functions related to oxidative metabolism that have not previously been shown concomitancy.