Computer tomographic investigation of subcutaneous adipose tissue as an indicator of body composition

<p>Abstract</p> <p>Background</p> <p>Modern computer tomography (CT) equipment can be used to acquire whole-body data from large animals such as pigs in minutes or less. In some circumstances, computer assisted analysis of the resulting image data can identify and measure anatomical features. The thickness of subcutaneous adipose tissue at a specific site measured by ultrasound, is used in the pig industry to assess adiposity and inform management decisions that have an impact on reproduction, food conversion performance and sow longevity. The measurement site, called "P2", is used throughout the industry. We propose that CT can be used to measure subcutaneous adipose tissue thickness and identify novel measurement sites that can be used as predictors of general adiposity.</p> <p>Methods</p> <p>Growing pigs (<it>N </it>= 12), were each CT scanned on three occasions. From these data the total volume of adipose tissue was determined and expressed as a proportion of total volume (fat-index). A computer algorithm was used to determined 10,201 subcutaneous adipose thickness measurements in each pig for each scan. From these data, sites were selected where correlation with fat-index was optimal.</p> <p>Results</p> <p>Image analysis correctly identified the limits of the relevant tissues and automated measurements were successfully generated. Two sites on the animal were identified where there was optimal correlation with fat-index. The first of these was located 4 intercostal spaces cranial to the caudal extremity of the last rib, the other, a further 5 intercostal spaces cranially.</p> <p>Conclusion</p> <p>The approach to image analysis reported permits the creation of various maps showing adipose thickness or correlation of thickness with other variables by location on the surface of the pig. The method identified novel adipose thickness measurement positions that are superior (as predictors of adiposity) to the site which is in current use. A similar approach could be used in other situations to quantify potential links between subcutaneous adiposity and disease or production traits.</p

Chemical composition and antibacterial activity of red murta (Ugni molinae Turcz.) seeds: an undervalued Chilean resource

Murta (Ugni molinae Turcz) is an endemic Chilean specie mostly used in medical, cosmetic, and food industries. However, during the industrial processing of murta fruits, the biomass containing the seeds is discarded as an industrial byproduct that does not find significant uses yet. This work is a first approach to valorize murta biomass through the identification and quantification of principal chemical constituents and exploring their antibacterial properties. The proximal analysis revealed that murta seeds exhibited significant content of raw fiber (64%), crude fat (14%), crude protein (12%), and low levels of ashes (1.5%) and minerals (0.04-0.23%). Dietary fiber was mainly composed of lignin, cellulose, pectin, and hemicellulose. Polyunsaturated fatty acids (89.0%), monounsaturated fatty acids (7.7%), and saturated fatty acids (3.3%) were the main constituents of seed oils. The arginine, asparagine, glutamic acid, and glycine were the primary protein constituent amino acids. Tannin fractions, total polyphenolic content, and oxygen radical absorbance capacity as antioxidant activity were measured. The chromatographic and mass spectrometric analysis (HPLC-MS/MS) confirmed the presence of several phenolic compounds like phenolic acids, flavonols, flavones, proanthocyanidins, and high molecular weight polyphenols. The murta seed extract showed high antibacterial activity against both Gram positive (Staphylococcus aureus, Bacillus cereus, and Streptococcus pyogenes) and Gram negative (Escherichia coli, Salmonella typhi, and Pseudomonas aeruginosa) bacterial strains. Murta seeds could be considered as a new source of nutritional components and bioactive compounds for different nutraceutical and food applications.Grant CONICYT PIA/APOYO CCTE FB17000