Meat quality in relation to swine well-being after transport and during lairage at the slaughterhouse

Meat Science, 2018, 142, 38-43

DOI:10.1016/j.meatsci.2018.04.005

Cortisol and corticosterone in saliva were evaluated as pig stress biomarkers, using pig genotype (Duroc, L62 or Pietrain) and lairage time in the slaughterhouse (0, 2.0, 4.0 or 6.0 h) as controlled variables. Although some pigs were found to be carriers of stress susceptibility, all were healthy heterozygous individuals. Pre-slaughter transport increased cortisol levels in saliva above 3.0 μg/L (medium stress), and 4.0 h of lairage in the slaughterhouse raised them above 6.0 μg/L, whereas corticosterone concentrations exceeded 4 μg/L, which are suggestive of high stress. The highest cortisol levels were detected in the Duroc genotype. Other factors such as food deprivation, background noise, the presence of a large number of animals waiting to be slaughtered, mixing with unfamiliar animals or recent mixing of genders may also influence stress. Corticosterone proved a reliable indicator of high stress only. Meat quality from the pig breeds studied was not affected by lairage in the slaughterhouse for up to 6.0 h.

Sepia ink as a surrogate for colloid transport tests in porous media

Journal of Contaminant Hydrology, 191, 2016, 88–98

http://dx.doi.org/10.1016/j.jconhyd.2016.05.005

We examined the suitability of the ink of Sepia officinalis as a surrogate for transport studies of microorganisms and microparticles in porous media. Sepia ink is an organic pigment consisted on a suspension of eumelanin, and that has several advantages for its use as a promising material for introducing the frugal-innovation in the fields of public health and environmental research: very low cost, non-toxic, spherical shape, moderate polydispersivity, size near large viruses, non-anomalous electrokinetic behavior, low retention in the soil, and high stability.

Electrokinetic determinations and transport experiments in quartz sand columns and soil columns were done with purified suspensions of sepia ink. Influence of ionic strength on the electrophoretic mobility of ink particles showed the typical behavior of polystyrene latex spheres. Breakthrough curve (BTC) and retention profile (RP) in quartz sand columns showed a depth dependent and blocking adsorption model with an increase in adsorption rates with the ionic strength. Partially saturated transport through undisturbed soil showed less retention than in quartz sand, and matrix exclusion was also observed. Quantification of ink in leachate fractions by light absorbance is direct, but quantification in the soil profile with moderate to high organic matter content was rather cumbersome.

We concluded that sepia ink is a suitable cheap surrogate for exploring transport of pathogenic viruses, bacteria and particulate contaminants in groundwater, and could be used for developing frugal-innovation related with the assessment of soil and aquifer filtration function, and monitoring of water filtration systems in low-income regions.