Growth performance and pork fat quality as measured by three methods of pigs fed 20% DDGS and slaughtered using a standard industry split marketing strategy.

A total of 40 pens containing 22 crossbred barrows (initial BW = 43.07 ± 1.61 kg; PIC 1050 × PIC 337 genetics) were housed in a commercial wean to finish facility. Pens were randomly allotted to dietary treatments in a 2 × 3 factorial arrangement with 2 levels of dried distillers grains with solubles (DDGS; 0% or 20%) and chosen for 1 of 3 marketing cuts removing 4, 8, and 10 animals from each pen. Fat tissue samples were removed from the anterior tip of the jowl and posterior to the sternum on the belly edge 1d postmortem. Fatty acid composition was determined via the Folch method, and iodine values (IV) were calculated from chemical titrations, fatty acid profile (GC IV), and in-plant Bruker near-infrared (NIR) spectroscopy. Pearson's correlation coefficients for IV determination methods were estimated. Inclusion of 20% DDGS did not change ( > 0.05) growth performance, whereas marketing cut affected performance, with the second cut producing the most efficient pigs ( < 0.01). Total SFA and MUFA concentrations were higher ( < 0.01) in belly and jowl fat from pigs fed 0% DDGS. Total PUFA and the PUFA:SFA in belly and jowl fat was higher ( < 0.01) when 20% DDGS was fed. Dried distillers grains with solubles inclusion increased IV in belly and jowl as determined by all 3 methods. Regardless of dietary treatment or fat depot, Pearson correlation coefficients between titration and GC IV, titration and NIR, and GC IV and NIR were 0.46 ( < 0.01), 0.68 ( < 0.01), and 0.43 ( < 0.01), respectively. These correlations suggest methods may rank samples equally but do not provide the same absolute IV. Belly fat had a lower IV ( < 0.01) than jowl fat using titration or GC IV methods, suggesting pigs have varied degrees of physiological maturity at specific fat depots when weight end points are used during the finishing phase. In conclusion, feeding 20% DDGS negatively affected fat quality but not growth performance, and marketing time changed growth performance.

Beef muscle isolation has no detrimental effect on premium ground beef programs.

This experiment evaluated whether isolating certain muscles from the chuck for retail sale and excluding them from ground beef mix changes the number of days that ground chuck is acceptable to consumers. Chucks were harvested from twenty-four beef steers, and were allocated to either traditional or innovative fabrication methods. Resulting ground beef patties were stored in retail simulation conditions for 7days to determine color and oxidative stability. Raw patties were analyzed for thiobarbituric acid reactive substances (TBARS), oxymyoglobin concentration, objective color by Minolta Chromameter, and by a trained sensory panel for odor, color and percent discoloration. No differences (P>0.05) were observed between traditional and innovative style patties for TBARS, sensory odor or color, or oxymyoglobin concentration. Minolta Chromameter readings revealed more substantial fading (P<0.05) in traditional patties compared with innovative style patties. This study demonstrated that removing certain muscles from the ground chuck mix does not cause detrimental consequences in resulting ground chuck patties.

Robocasting of biomimetic hydroxyapatite scaffolds using self-setting inks.

Low temperature self-setting ceramic inks have been scarcely investigated for solid freeform fabrication processes. This work deals with the robocasting of alpha-tricalcium phosphate/gelatine reactive slurries as a bioinspired self-setting ink for the production of biomimetic hydroxyapatite/gelatine scaffolds. A controlled and totally interconnected pore network of ∼300 µm was obtained after ink printing and setting, with the struts consisting of a micro/nanoporous matrix of needle-shaped calcium deficient hydroxyapatite crystals, with a high specific surface area. Gelatine was effectively retained by chemical crosslinking. The setting reaction of the ink resulted in a significant increase of both the elastic modulus and the compressive strength of the scaffolds, which were within the range of the human trabecular bone. In addition to delaying the onset of the setting reaction, thus providing enough time for printing, gelatine provided the viscoelastic properties to the strands to support their own weight, and additionally enhanced mesenchymal stem cell adhesion and proliferation on the surface of the scaffold. Altogether this new processing approach opens good perspectives for the design of hydroxyapatite scaffolds for bone tissue engineering with enhanced reactivity and resorption rate.

Dependence of mechanical compressive strength on local variations in microarchitecture in cancellous bone of proximal human femur.

Human cancellous bone is a heterogeneous material. Despite this, most of the published studies report correlations between mechanical properties and morphometric parameters averaged on the whole specimen. This work investigated whether local variations in morphometric parameters were linked to the localized failure regions of cancellous bone. Additionally, it was examined whether local values of morphometric parameters can predict the ultimate stress better than the average bone volume fraction (BV/TV). Cylindrical cancellous bone specimens extracted along the primary compressive group of human femoral heads were studied. These were microCT-imaged to assess the morphometric parameters, compressed to determine the ultimate stress, and rescanned by microCT to visualize the failure region. Failure involved slightly less than half of the free height of the specimens. Significant differences were found in the morphometric parameters calculated in the failure and in the non-failure regions. The cross-sections containing minimum BV/TV values were those most often located inside the failure region (83%, p<0.001). Regression analysis confirmed that variations in BV/TV best describe variations in ultimate stress (R2=0.84) out of the averaged morphometric parameters. The prediction of ultimate stress increased when minimum or maximum values of the morphometric parameters were taken, with the highest prediction found by considering the minimum BV/TV (R2=0.95). In conclusion, due to the heterogeneity of cancellous bone, there may exist regions characterized by a different microarchitecture, where the bone is weaker and consequently is more likely to fail. These regions mostly contain minimum values in BV/TV, which were found to predict ultimate stress better than average BV/TV.

Structural parameters and mechanical strength of cancellous bone in the femoral head in osteoarthritis do not depend on age.

For normal bone, aging has been associated with a decrease of both density and failure strength, and with the development of pathologies such as osteoporosis. Conversely, it has been reported that another common disease, osteoarthritis, may alter these age-related changes in cancellous bone, suggesting that it may have a protective role against osteoporosis and the correspondent fracture risk. It was reported that in the principal compressive region of the femoral head in osteoarthritis the bone density does not depend on age. However, it is not clear if this independence on age of the cancellous bone density corresponds also to a reduced dependence on age of the strength to failure. The present work examined cancellous bone from the principal compressive region of the femoral head of 37 patients having severe osteoarthritis. The aim was (1) to investigate the dependence on age of both the structural parameters and the ultimate stress and (2) to investigate the relationships between the ultimate stress and the structural parameters. Using X-ray microcomputed tomography, three-dimensional structural parameters, such as bone volume fraction, direct trabecular thickness and structure model index were calculated. Then the specimens were compressed to failure to determine the ultimate stress. It was found that none of the investigated structural parameters did depend on age, and also the ultimate stress did not depend on age (p>0.05 for all regressions on age). In addition, the ultimate stress was significantly correlated with the structural parameters, primary with the minimum bone volume fraction and the average bone volume fraction (R(2)=0.95 and R(2)=0.84, respectively). These findings show that severe osteoarthritis or a related factor may change the age dependences of both the structural parameters and the mechanical properties usually reported for normal cancellous bone. These results suggest for this pathology to have a protective role against the age-related decrease in density, the age-related deterioration of the microarchitecture and the age-related decrease of the failure strength for the cancellous bone in the principal compressive region of the human femoral head.

Anaerobic bacteria commonly colonize the lower airways of intubated ICU patients.

OBJECTIVES: To investigate respiratory tract colonization by aerobic and anaerobic bacteria in mechanically ventilated patients. METHODS: Bacterial colonization of the stomach and the respiratory tract was qualitatively and quantitatively analyzed over time in 41 consecutive mechanically ventilated patients in a Swedish intensive care unit (ICU), with special emphasis on elucidation of the role of anaerobic bacteria in the lower respiratory tract. Samples were taken from the oropharynx, gastric juice, subglottic space and trachea within 24 h (median 14 h) of intubation, and then every third day until day 18 and every fifth day until day 33. RESULTS: The patients were often heavily colonized with microorganisms not considered to belong to a healthy normal oropharyngeal and gastric flora on admission to the ICU. A majority harbored enterococci, coagulase-negative staphylococci and Candida spp. in at least one site on day 1. Anaerobic bacteria, mainly peptostreptococci and Prevotella spp., were isolated from subglottic and/or tracheal secretions in 59% of the patients. Different routes of tracheal colonization for different groups of microorganisms were found. Primary or concomitant colonization of the oropharynx with staphylococci, enterococci, enterobacteria and Candida was often seen, while Pseudomonas spp., other non-fermenting Gram-negative rods and several anaerobic species often primarily colonized the trachea, indicating exogenous or direct gastrointestinal routes of colonization. CONCLUSIONS: Mechanically ventilated patients were heavily colonized in their lower airways by potential pathogenic microorganisms, including a high load of anaerobic bacteria. Different routes of colonization were shown for different species.