Determination of N-acetylneuraminic and N-glycolylneuraminic acids in unprocessed milk of four cattle breeds.

This research communication reports concentrations of two sialic acids (SA), N-acetylneuraminic (Neu5Ac) and N-glycolylneuraminic (Neu5Gc), in fresh milk from different cow breeds throughout lactation. According to published studies, the two SA types found in animal-derived products have diverse and conflicting effects on human health, but SA content is not routinely analysed in individual milk cows samples. We measured the content of Neu5Ac and Neu5Gc in milk from Holstein Friesian (HO), Simmental (SM), Simmental × Holstein crossbred (SM×HO), and Podolica (POD) cows at 60 and 120 d following calving. HO, SM and SM×HO were reared in an intensive production while POD were raised in an extensive system. Results showed that total Neu5Ac was overall thirty times more abundant than Neu5Gc, and their concentrations were higher at 120 d than at 60 d (P < 0.001). Neu5Gc values were greater in HO, SM, and SM × HO than in POD (P < 0.001), while HO had a higher Neu5Ac value than the other three breeds (P < 0.001). These findings shed light on the differences in SA content among cow breeds and lay the groundwork for future research to select animals that produce milk with desirable characteristics for human health.

Near-Infrared Reflectance Spectroscopy for Predicting the Phospholipid Fraction and the Total Fatty Acid Composition of Freeze-Dried Beef.

Research on fatty acids (FA) is important because their intake is related to human health. NIRS can be a useful tool to estimate the FA of beef but due to the high moisture and the high absorbance of water makes it difficult to calibrate the analyses. This work evaluated near-infrared reflectance spectroscopy as a tool to assess the total fatty acid composition and the phospholipid fraction of fatty acids of beef using freeze-dried meat. An average of 22 unrelated pure breed young bulls from 15 European breeds were reared on a common concentrate-based diet. A total of 332 longissimus thoracis steaks were analysed for fatty acid composition and a freeze-dried sample was subjected to near-infrared spectral analysis. 220 samples (67%) were used as a calibration set with the remaining 110 (33%) being used for validation of the models obtained. There was a large variation in the total FA concentration across the animals giving a good data set for the analysis and whilst the coefficient of variation was nearly 68% for the monounsaturated FA it was only 27% for the polyunsaturated fatty acids (PUFA). PLS method was used to develop the prediction models. The models for the phospholipid fraction had a low R2p and high standard error, while models for neutral lipid had the best performance, in general. It was not possible to obtain a good prediction of many individual PUFA concentrations being present at low concentrations and less variable than other FA. The best models were developed for Total FA, saturated FA, 9c18:1 and 16:1 with R2p greater than 0.76. This study indicates that NIRS is a feasible and useful tool for screening purposes and it has the potential to predict most of the FA of freeze-dried beef.

Quality assessment of escaping silver eel (Anguilla anguilla L.) to support management and conservation strategies in Mediterranean coastal lagoons.

Silver eel samples, collected from the lagoons of Fogliano and Caprolace (Italy), were investigated for a broad range of contaminants (29 polychlorinated biphenyls, 9 polybrominated diphenyl ethers, 5 dichlorodiphenyltrichloroethane, 5 chlordanes, hexachlorobenzene, 3 hexachlorocyclohexane, and 5 metals). Concentrations of targeted compounds stand for a general low contamination pattern. Infestation by Anguillicola crassus and virus infections were also examined. No parasite infestation was found, while infected silver eels had a low prevalence for EVEX, and, for the first time in the Mediterranean area, for AngHV-1. Overall, a good quality status of escaping silver eels, for both lagoons, was highlighted by the use of integrative Indexes. A quality assessment of the ecological status of the two lagoons was carried out developing an expert judgment approach, in order to characterize the habitat of eel stocks. A Final Pressure Index was derived, whose values showed an overall limited global anthropogenic impact acting on both lagoons. Results stand for the suitability of an integrated approach to assess lagoon habitats and eel local stocks quality. This could be proposed as a tool to identify sites yielding high quality eel spawners in the Mediterranean region, in order to set up suitable management frameworks, providing elements to appraise and discuss the potential of coastal lagoons in the Mediterranean region towards the recovery of the eel global stock.

Effect of pasture and intensive feeding systems on the carcass and meat quality of buffalo.

OBJECTIVE: This work was carried out to evaluate the effect of pasture (PA) feeding on buffalo meat quality compared with buffaloes reared intensively with the use of corn silage as a forage base or alternatively with polyphite meadow hay (PH). METHODS: Thirty Mediterranean bull buffaloes were distributed into three experimental diet groups: maize silage (MS), PH, and PA. The animals were slaughtered at a live weight of 250 kg, and carcass and meat quality were evaluated. After 7 days of ageing, physical and chemical parameters of longissimus thoracis muscle were determined. To evaluate lipid oxidation the thiobarbituric acid reactive substances was tested at 7 and 14 days, and also the fatty acid profile was recorded by gas chromatography. RESULTS: The PA group, even if it showed carcass parameters lower than those of the silage maize group, reported a good meat percentage (60.59% vs 58.46%, respectively) and lower fat percentage (p<0.001). PA-fed animals showed meat redness, and even if only on raw meat, shear force was higher than the others. Low values of conjugate linoleic acid, polyunsaturated fatty acids, and n-3 were reported in the silage maize group. Principal component analysis (PCA) clearly showed the influence of different diets on meat quality, and PCA1 and PCA2 explained 82% of the variability. CONCLUSION: Buffaloes reared on PA had meat with high nutritional value even if they showed poor carcass performance compared to the animals fed on MS. Buffaloes fed on polyphite hay were in an intermediate position, similar to grazing animals, according to the same nutritional determinations.

An index to measure the activity attitude of broilers in extensive system.

In organic poultry production it is important to rear animals with a dynamic attitude to take advantage of outdoor areas. Farmers are reluctant to use such strains due to their lower productivity and older slaughtering age. However, fast growing lines grown in organic system often suffer poor health and welfare conditions. The kinetic metabolism of chickens is correlated with different types of muscle fiber: type I (in red muscles or oxidative) for prolonged and moderate movement and type II (in white muscles or glycogenic) for fast movements. Red muscle metabolism produces energy mainly by ß-oxidation of Highly Unsaturated n-3 Fatty Acids (HUFA). Accordingly, kinetic activity causes higher consume of HUFA in red muscles than in white muscles, so the ratio between n-3 HUFA and their precursor C18:3 n-3 (ALA) is likely to be smaller in red than in white muscles. However, these ratios are highly affected by the environment. To reduce the effect of environmental variables, we propose an "Activity index" as the difference between n-3 HUFA/ALA in white and red muscle within the same bird. This index, measured after slaughtering, should represent the activity performed by the chicken during its life. Given that birds in good health had the possibility of moving, the "Activity index" would measure the activity actually performed by the animals. Should birds of a given strain show a higher activity level, this would be an indication of the suitability of that strain to outdoor systems. This work verified the application of this "Activity index" on 90 birds from 6 genetic strains with known kinetic behavior reared in an experimental farm. The "Activity index" was also tested on chicken strains collected form commercial organic farms. The results confirmed that strains recognized for higher kinetic attitude actually walked more and their behavior was clearly detected by the "Activity index" estimated from their muscles.

Microbiological and physicochemical parameters for predicting quality of fat and low-fat raw ground beef during refrigerated aerobic storage.

The aim of the current study was to identify quality indicators of fat (14.50 ± 0.75%) and low-fat (4.79 ± 0.63%) raw ground beef by monitoring changes in physicochemical and microbiological parameters during aerobic refrigerated storage, such as water-holding capacity, pH, thiols, carbonyl compounds, thiobarbituric acid reactive substances (TBARS), metmyoglobin, deoxymyoglobin, oxymyoglobin color indices, pseudomonads, Brochothrix thermosphacta, and total viable counts. Meat packaged in air-permeable polyethylene plastic film was stored under controlled isothermal conditions (0, 5, 10, and 15 °C). A population level of pseudomonads equal to 7.0 ± 0.5 log10 colony forming units (CFU)/g was considered as the potential spoilage level. Using principal component analysis, samples were distinguished on the basis of their microbial load. A significant positive correlation between microbial population and carbonyls, metmyoglobin, TBARS, water-holding capacity, and a negative correlation with thiols and color parameters (L* , chroma) were observed. Two different approaches were followed to estimate the quality status of samples: (i) the partial least square (PLS) regression with R2 of 0.93 and root mean square error prediction of 0.44 for pseudomonads, using the above physicochemical characteristics as the dominant input variables, which allowed prediction of the microbiological status of ground beef regardless of time-temperature storage profile and fat content, and (ii) a square-root-type model (adjusted R2 of 0.952) that satisfactorily predicted the growth of spoilage pseudomonads under isothermal and dynamic conditions, regardless of the above physicochemical changes. The above results suggest that depending on the available input data, the two modeling approaches can accurately (and complementarily) assess quality of aerobically stored ground beef. PRACTICAL APPLICATION: Changes in appearance and quality of fat and low-fat raw ground beef are associated with physicochemical alteration and/or microbial growth. The study provides two different modeling approaches that can be integrated in an intelligent interface of the refrigerator having specific colorimetric and/or temperature sensors, to evaluate in a convenience way the quality of stored meat thus reducing domestic waste: the partial least square model was based on physicochemical parameters (particularly chroma, metmyoglobin, and thiobarbituric acid reactive substances), while the square root model was based on the time-temperature conditions during storage.

Physical and nutritional properties of buffalo meat finished on hay or maize silage-based diets.

The current study examines the effect of different finishing diets (hay- vs. maize-silage on meal ration) on carcass quality, physical, chemical and sensory properties, and fatty acid profiles of buffalo meat. Twenty male Italian Mediterranean buffaloes (246 ± 9.00 kg live weight) were distributed at random into two groups at the beginning of the finishing period (368 ± 20 days). The buffaloes were offered two finishing diets: a maize silage (MS) or an alfalfa hay (AH) diet. No significant differences were found between dietary treatments for live and carcass weight. Meat chemical composition was influenced by dietary treatment. A higher fat content was detected in meat from animals finished with MS than AH (P < 0.05). Overall, the data indicated differences between the fatty acid profiles of meat as a consequence of different feeding systems. The higher fat deposition in the MS group resulted in meat with a less favorable fatty acid profile (i.e. a lower polyunsaturated/saturated fatty acid ratio and α-linolenic fatty acid content) in relation to human health compared with meat from animals fed the AH diet.

HRMAS-NMR spectroscopy and multivariate analysis meat characterisation.

¹H-High resolution magic angle spinning-nuclear magnetic resonance spectroscopy was employed to gain the metabolic profile of longissimus dorsi and semitendinosus muscles of four different breeds: Chianina, Holstein Friesian, Maremmana and Buffalo. Principal component analysis, partial least squares projection to latent structure - discriminant analysis and orthogonal partial least squares projection to latent structure - discriminant analysis were used to build models capable of discriminating the muscle type according to the breed. Data analysis led to an excellent classification for Buffalo and Chianina, while for Holstein Friesian the separation was lower. In the case of Maremmana the use of intelligent bucketing was necessary due to some resonances shifting allowed improvement of the discrimination ability. Finally, by using the Variable Importance in Projection values the metabolites relevant for the classification were identified.

Chianina beef tenderness investigated through integrated Omics.

In the present study we performed an integrated proteomics, interactomics and metabolomics analysis of Longissimus dorsi tender and tough meat samples from Chianina beef cattle. Results were statistically handled as to obtain Pearson's correlation coefficients of the results from Omics investigation in relation to canonical tenderness-related parameters, including Warner Bratzler shear force, myofibrillar degradation (at 48 h and 10 days after slaughter), sarcomere length and total collagen content. As a result, we could observe that the tender meat group was characterized by higher levels of glycolytic enzymes, which were over-phosphorylated and produced accumulation of glycolytic intermediates. Oxidative stress promoted meat tenderness and elicited heat shock protein responses, which in turn triggered apoptosis-like cascades along with PARP fragmentation. Phosphorylation was found to be a key process in post mortem muscle conversion to meat, as it was shown not only to modulate glycolytic enzyme activities, but also mediate the stability of structural proteins at the Z-disk. On the other hand, phosphorylation of HSPs has been supposed to alter their functions through changing their affinity for target interactors. Analogies and breed-specific differences are highlighted throughout the text via a direct comparison of the present results against the ones obtained in a parallel study on Maremmana Longissimus dorsi. It emerges that, while the main cornerstones and the final outcome are maintained, post mortem metabolism in tender and tough meat yielding individuals is subtly modulated via specific higher levels of enzymes and amino acidic residue phosphorylation in a breed-specific fashion, and whether calcium homeostasis dysregulation was a key factor in Maremmana, higher early post mortem phosphocreatine levels in the Chianina tender group could favor a slower and prolonged glycolytic rate, prolonging the extent of the minimum hanging period necessary to obtain tender meat from this breed by a few days.

Relationship between collagen characteristics, lipid content and raw and cooked texture of meat from young bulls of fifteen European breeds.

Variations in texture were determined for 10 day aged raw and cooked Longissimus thoracis (LT) muscle from 436 bulls of 15 European cattle breeds slaughtered at an age of 13-16 months. Variations in texture were related to differences in pH 24 h post-mortem, sarcomere length, collagen characteristics and lipid content. The shear force of cooked meat samples varied from 43.8 to 67.4 N/cm². Simmental, Highland and Marchigiana cattle had the highest shear force values and Avileña-Negra Ibérica, Charolais, Casina and Pirenaica cattle had the lowest values. Cooked meat toughness showed a weak negative correlation to lipid content (P<0.001) but no correlation to collagen characteristics. Raw meat texture measured by compression correlated positively (P<0.001) with total and insoluble collagen. In conclusion, collagen characteristics showed correlation to raw meat texture but not to cooked meat toughness of LT muscle in European young bulls.