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Dietary C18 unsaturated fatty acids are extensively biohydrogenated by rumen microbiota into 18:0 and trans-18:1 isomers. Usually, the biohydrogenation (BH) pathways produce mostly 18:0 and trans-11 18:1 as the main intermediate. However, when fed lowforage diets that decrease the rumen pH, the main BH intermediate often is the trans-10 18:1 isomer. This change in BH, called the trans-10 shift, is associated with milk fat depression, but despite that, little is known about the triggers of the trans-10 shift and its ecological role in rumen microbiota. Microbiota stressed by low rumen pH may benefit from increased trans-18:1 availability favoring the production of the trans-18:1 isomer with a slower rate of BH. Thus, we hypothesize that at low rumen pH conditions, the BH of trans-10 18:1 will be slower than that of trans-11 18:1. We tested that with an in vitro experiment using batch incubation in Hungate tubes, replicated in 5 wk. In each run, 24 tubes were allocated at 6 treatments and 4 incubation times (0, 6, 24 and 48 h). The treatments resulted from the combination of 2 buffering solution pH (6.74 vs. 5.85) and 3 substrates: 1) Control (60 mg feed DM) 2) T10 (Control plus 1.2 mg of trans- 10 18:1) and 3) T11 (Control plus 1.2 mg of trans-11 18:1). Volatile fatty acids (VFA) and long-chain fatty acids were analyzed by gas chromatography. Data were analyzed using the 2 × 3 factorial arrangement for each incubation time. Low pH resulted in less 30 to 37% DM disappearance than those with high pH at all incubation times (P < 0.05). The decrease in VFA with low pH was less expressive (≈17%) and only evident at 24 and 48 h incubation times. The low pH also decreased (P < 0.05) the BH of 18:1n-9 (less ≈47 to 53%), 18:2n-6 (less 30 to 34%) and 18:3n-3 (less 20 to 22%) at 24h and 48h incubation times, respectively. The disappearance of trans-11 18:1 was 14.6% at 6 h, 29.0% at 24 h and 32.8% at 48 h and was not affected by pH. The disappearance of trans-10 18:1 was dependent on pH. At 6 h and high pH the disappearance of both was similar, but at low pH the disappearance of trans-10 18:1 was much less (9.8%) than that of trans-11 18:1. However, at 48 h and low pH, the disappearance was similar between isomers and the disappearance of trans-10 18:1 was much greater (46.6%) than trans- 11 18:1. In summary, the BH of trans-10 18:1 is less at low pH than at high pH, and this could in part explain its abundance in some practical ruminant feeding conditions. Acknowledgements: Fundação para a Ciência e a Tecnologia (FCT) funding through PTDC/ CAL-ZOO/29654/2017(RumOmics), PTDC/CALZOO/ 4515/2021(Gene2Rumen), UIDB/00276/2020 (CIISA), and LA/P/0059/2020 (AL4Animals) projects. [ABSTRACT FROM AUTHOR]

Simple Summary: Omega-3 polyunsaturated fatty acids (n-3 PUFAs), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been increasingly studied due to their beneficial health effects. N-3 PUFAs are particularly abundant in the brain and retina, where they play various roles that are important to the maintenance of normal function in those organs. The present study aimed to evaluate the FA profile of lamb brain and retinal tissues after they were fed three experimental diets supplemented with an EPA-rich microalga for 21 days. The microalga was delivered in a different format in each one of the diets (oil, spray-dried and freeze-dried biomass); therefore, its efficiency in altering the FA profile of brain and retina was evaluated for each diet. Overall, our results demonstrated that the brain EPA content remained unchanged after EPA supplementation, in contrast with the retinal EPA, which was very responsive to microalga supplementation. Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have special physiological functions in both brain and retinal tissues that are related to the modulation of inflammatory processes and direct effects on neuronal membrane fluidity, impacting mental and visual health. Among them, the long-chain (LC) n-3 PUFAs, as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are of special importance. Scarce data are available about the fatty acid (FA) composition of the ruminant brain in response to dietary intervention. However, we decided to examine the brain and retina FA composition of lambs supplemented with an EPA-rich microalga feed for 21 days, as it is known that despite the extensive biohydrogenation of dietary PUFAs in the rumen, ruminants can selectively accumulate some n-3 LC-PUFAs in their brain and retinal tissues. Twenty-eight male lambs were fed a control diet, or the same diet further supplemented with Nannochloropsis sp. microalga. Their brains and retina were collected for FA characterization. Overall, the brain FA profile remained unchanged, with little alteration in omega-3 docosapentaenoic acid (DPA) enhancement in both the hippocampus and prefrontal cortex. Retinal tissues were particularly responsive to the dietary intervention, with a 4.5-fold enhancement of EPA in the freeze-dried-fed lambs compared with the control lambs. We conclude that retinal tissues are sensitive to short-term n-3 PUFA supplementation in lambs. [ABSTRACT FROM AUTHOR]

Simple Summary: The consumption of edible dormouse (Glis glis L.) meat is accepted as part of the tradition and heritage of certain regions of southern Europe. Since the literature regarding the composition of dormouse meat is scarce and no studies reported the fatty acid composition of muscle, this study aimed to investigate the fatty acid composition of edible dormouse m. biceps femoris in both sexes. Furthermore, some fatty acids suggest feeding of an edible dormouse on a specific group of plants. This work can contribute to increase the knowledge on edible dormouse physiology and nutritional traits as well as to update food composition database. This study aimed to investigate the fatty acid (FA) composition of edible dormouse m. biceps femoris in both sexes. More than 20 FA were identified in the muscle, with the 18:1cis-9 (oleic acid) being the most abundant in both sexes, comprising more than 50% of total FA in muscle. The most dominated FA were monounsaturated (MUFA), followed by saturated FA (SFA) and polyunsaturated FA (PUFA), reaching 54.8%, 25.43% and 19.8% of total FA, respectively. Sums of PUFA and n-3 PUFA tended (p > 0.05) to be higher in males than in females. There were no significant differences between sexes on the FA composition. Nevertheless, the 18:2n-6 tended to differ between sexes (p = 0.063). Several long-chain PUFA (LC-PUFA) were detected in dormouse muscle, with the 20:4 n-6 (arachidonic acid, AA) and the 22:6 n-3 (docosahexaenoic acid, DHA) being the most abundant in both sexes. The relatively high stearoyl-CoA desaturase (SCD) indexes and the large concentration of 18:1cis-9 in dormouse muscle tissues might point to a low mobilization of the SCD products. Furthermore, finding the unusual FA 20:3 ∆5,∆11,∆14, suggests feeding on leaf and wood lipids of Coniferophytes. We demonstrated sexual size monomorphism in edible dormouse. The literature regarding the composition of dormouse meat is scarce and no studies reported the FA composition of muscle, thus, this work can contribute to increasing the knowledge on edible dormouse physiology and nutritional traits. [ABSTRACT FROM AUTHOR]

Campylobacter on poultry meat needs to be controlled to reduce the risk of infection caused by the consumption of chicken meat. Pulsed light (PL) application on poultry meat was studied to control Campylobacter spp. The effect of this technology was evaluated regarding poultry meat colour and volatile compound changes. Two breast sample groups were prepared: inoculated with Campylobacter (107 bacteria of Campylobacter jejuni strains) and not inoculated. Samples were submitted to PL, five pulses/s of 300 ms, 1 Hz, and 1 J/cm2 in the apparatus, PL Tecum unit (Claranor). A response surface experimental design was applied regarding the factors of voltage (1828 to 3000 W) and distance to the source UV lamp (2.6 to 5.4 cm). The binomial factorial treatment (voltage and distance) with PL induced different energy doses (fluence J/cm2) received by samples, 2.82 to 9.67 J/cm2. Poultry meat pulsed light treated had a significant decrease of Enterobacteriaceae counts. The treatments applied were unable to reduce 1 log Campylobacter cfu/g of poultry meat. The poultry meat PL treated became slightly light, redder, and yellower than those not treated. PL can decrease the proportion of aldehydes on total volatiles in meat, particularly on those associated with chicken-like, chicken skin-like, and sweet odour notes in fresh poultry meat. Further studies of PL with higher energy doses will be necessary to confirm if there are Campylobacter reductions and about poultry meat treated under storage to evaluate if volatile compounds can affect the flavour of PL-treated meat samples. [ABSTRACT FROM AUTHOR]

The trans-10 shift is a recognized deviation from the normal ruminal biohydrogenation (BH) pathways of the dietary polyunsaturated fatty acids (FA) in the rumen. This phenomenon leads to the formation of the harmful t10-18:1, which is detrimental to the health of the animal, instead of the beneficial t11-18:1, which has positive effects. The phenomenon known as the t10-shift has been observed in animals consuming diets that are high in starch but low in forage. Although consuming such similar diets, there exists a significant variability in t10-shift expression among animals. The reasons be- hind the t10-shift are not well understood. With the aim of finding biomarkers associated with t10-shift, this study utilized multiple levels of information, including lipidomics, metabolomics, and proteomics of ruminal contents. Rumen contents from male lambs (n = 16) distributed by two diets with distinct forage: concentrate ratios (20:80 and 80:20) were collected after 42 d on ad libitum feed. FA from rumen contents were prepared and analyzed by gas chromatography, metaproteomics analyzes were performed from rumen bacterial pellets using LC-MS/MS-based label-free quantification, and metabolomics analyzes were performed from rumen fluid supernatants using IMS-TOF technology. Multivariate analyses and correlations were performed using the Metaboanalyst R package. Several fatty acids, proteins, and metabolites showed a strong correlation with the proportion of t10-18:1 in rumen contents. Among fatty acids, 17:0, 14:0, a-15:0, and t15-18:1 were positively correlated, while t11-18:1, t11,c13-CLA and c9,t11-CLA showed negative correlation. The metabolites, thiamine aldehyde, mevinolinic acid, 2-hydroxy-2H-benzo[h] chromene-2-carboxylate, or biotin were positively correlated with t10-18:1, as well as proteins associated with gluconeogenesis, stress response or amino acid metabolism. This work provides, for the first time, a multi-level integrated view of t10-shift phenomena in sheep. Fundação para a Ciência e a Tecnologia (FCT) provided financial support through the research pro- jects PTDC/CAL-ZOO/29654/2017 (RumOmics), PTDC/CAL-ZOO/4515/2021 (Gene2Rumen), UIDB/00276/2020 (CIISA), UIDB/04129/2020 (LEAF), and LA/P/0059/2020 (AL4Animals) [ABSTRACT FROM AUTHOR]

This work evaluated the effects of dietary inclusion of microalga Chlorella vulgaris on post-weaning piglet growth performance and physiology. Noncastrated male piglets [n = 72; Piétrain × (Large White x Landrace), with 7.4±1.03 kg body weight (BW); 28 d] were blocked by BW and randomly assigned to 24 pens (3 animals/pen, n = 8) and each pen to one of three experimental diets, fed ad libitum: (C) Control diet (wheat/corn/soybean meal-based), (CV2.5) 2.5% C. vulgaris inclusion and (CV5) 5% C. vulgaris inclusion. The trial lasted 5 wk, with BW and feed intake determined weekly. Total tract apparent digestibility (TTAD) was determined using chromic oxide as external marker. Following wk 5 (67 d), one piglet per pen (median BW) was slaughtered and visceral organs, gastrointestinal contents and Longissimus lumborum muscle were sampled. Untargeted 1H NMR metabolomics study characterized hepatic polar metabolome following CHCl3:MetOH:H2O extraction. Multivariate analysis (PCA, PLS-DA) and identification of important metabolites enabled pathway analysis. Intramuscular fatty acid composition was determined by gas-liquid chromatography after direct transesterification to methylesters and extraction. Growth performance indicators, TTAD, digesta viscosity and pH were determined and analyzed by ANOVA with values reported as average ± SEM and significance at P ≤ 0.05. Diet did not affect average daily BW gain (566 ± 1.6 g/d), average daily feed intake (711 ± 1.8 g/d), nor feed conversion ratio (1.28 ± 0.078). Viscosity of intestinal contents in upper small intestine (3.7 ± 0.19 mPa.s) and ileum (4.8 ± 0.26 mPa.s), as well as pH of stomach (4.1 ± 0.18), upper small intestine (5.7 ± 0.08), ileum (6.6 ± 0.07), cecum (5.7 ± 0.10) and colon contents (6.1 ± 0.08) were unaffected by diets, within each sampling site. Minor negative effects of microalgae inclusion were seen on digestibility of all feed fractions (1 to 9% difference, compared with Control), namely DM, OM, CP, CF, Ash, NDF and DE. In the muscle, animals fed 5% C. vulgaris presented greater concentrations of omega-3 polyunsaturated fatty acids (PUFA, 1.68 ± 0.112 % vs. 1.39 % of total FA) and no effect in omega-6 PUFA concentration, thus a greater ratio of Omega 3 to Omega 6 (0.052 ± 0.022 vs. 0.045), when compared with Control. Multivariate analysis of liver metabolomics showed significant clustering, clearly separating both microalgaefed groups from Control. The altered metabolic profile suggests activation of antioxidant pathways, as well as carbohydrate and amino acid metabolism with dietary inclusion of C. vulgaris. Particularly, levels of antioxidant metabolic markers as glutathione, sarcosine, betaine and their precursor amino acids point to an enhanced GSH-antioxidant system activation. Overall, results indicate that C. vulgaris inclusion in postweaning diets up to 5% does not penalize growth performance and can effectively be used in piglet nutrition. Furthermore, hepatic metabolomics suggest important bioactivity imparted by C. vulgaris dietary inclusion, potentially linking enhanced antioxidant systems in the liver with stable integration of PUFA in muscle, which may improve piglet health and pork quality. [ABSTRACT FROM AUTHOR]

Protected Designation of Origin (PDO) products are gaining importance due to their high quality and increased consumer concerns about sustainability. Arouquesa PDO beef is a local product with valued organoleptic traits that contributes to local heritage and economy in rural regions of Northern Portugal. Proteomic analysis provides insights on important metabolic pathways that can be related to the production system and be used to differentiate PDO beef from beef produced under standard systems such as those used with crossbreds. The aim of this work is to compare the proteome profile of Arouquesa PDO beef with beef from crossbred animals produced under standard conditions. Muscle samples (n = 10) were collected from the abattoir from male weaners slaughtered at 8.5 mo of age: five Arouquesa breed and five Limousine (n = 2) or Charolais (n = 3) crossbreds. Samples were analyzed using 2D-DIGE and spots showing differential accumulation (P-value < 0.05 and fold-change ± 1.5) were selected for identification using in-gel tryptic digest and LC-MS/MS identification. Meat quality parameters (pH, crude protein and total lipids) were also determined. Animal body weight was 62% heavier (P < 0.05) in crossbred animals (214 ± 5.47 kg). Arouquesa beef had reduced crude protein (17.52 ± 1.39 vs. 20.46 ± 1.44 g/100 g meat) and consequently a greater value of total lipids (8.39 ± 1.86 vs. 3.62 ± 2.44 g/100 g meat). Of the 34 protein spots showing differential accumulation, 13 had greater abundances in Arouquesa beef, whereas 21 were increased in the crossbred animals. Some of the up-regulated proteins in the Arouquesa beef are involved in glycolysis (GADPH, GPI, PGM1, TPI, ENO3) or in muscle structure (MYL1, MYLPF). The down-regulated proteins were mostly related to muscle structure (MYLPF, MYL6B, TNNT1), oxygen transport (HBA, HBB) or heat shock proteins (HSPB1). We also found for some proteins several differentially regulated proteoforms between breeds (MYLPF and TPI1), not all regulated in the same way. The proteins involved in glycolysis can indicate a decreased glycolytic potential of Arouquesa muscle leading to reduced glycogen degradation during post-mortem. The proteins related to muscle structure are generally associated with greater growth performances which was not expected as Arouquesa animals had lighter final body weights. However, MYL1 is also associated to increased tenderness as expectable in Arouquesa beef due to the production system based on early slaughter. The greater abundance of proteins related to oxygen metabolism in crossbred animals suggests a greater oxidative capacity which may be related to muscle fiber composition. In conclusion, the proteome profile of Arouquesa breed points to better beef quality traits compared with commercial beef; thus, contributing to increase product valorization. We found different proteins in the two groups related to specific metabolisms showing a breed-specific response allowing the improvement of the PDO products traceability. [ABSTRACT FROM AUTHOR]

The aim of this work was to develop functional couscous in a traditional Tunisian manner (hand rolling), enriched in algae biomass (6% w/w). Four Chlorella vulgaris (C. vulgaris) biomasses and one mixture of C. vulgaris and two macroalgae biomasses (Ulva rigida and Fucus vesiculosus) were used. The C. vulgaris strain was subjected to random mutagenesis and different culture conditions (Allmicroalgae), resulting in different pigmentations and biochemical compositions. Couscous samples were characterized in terms of nutritional properties, oscillatory rheology properties and digestibility. All biomasses provided a significant supplementation of nutrients and excellent acceptance. The enrichment resulted in lower firmness, higher viscoelastic functions (G0 and G”) and a significant improvement in the cooking quality. Major differences between couscous samples with different microalgae were observed in protein and mineral contents, fully meeting Regulation (EC) No. 1924/2006 requirements for health claims made on foodstuffs. The amount of digested proteins was also higher in algae-containing samples. The fatty acid profile of the enriched couscous varied in a biomass-specific way, with a marked increase in linolenic acid (18:3 ω3) and a decrease in the ω6/ω3 ratio. Sensory analysis revealed that microalgae-containing products could compete with conventional goods with an added advantage, that is, having an ameliorated nutritional value using algae as a “trendy” and sustainable ingredient. [ABSTRACT FROM AUTHOR]

Eicosapentaenoic acid (EPA) from freeze-dried biomass of Nannochloropsis oceanica microalgae resists ruminal biohydrogenation in vitro, but in vivo demonstration is needed. Therefore, the present study was designed to test the rumen protective effects of N. oceanica in lambs. Twenty-eight lambs were assigned to one of four diets: Control (C); and C diets supplemented with: 1.2% Nannochloropsis sp. oil (O); 12.3% spray-dried N. oceanica (SD); or 9.2% N. oceanica (FD), to achieve 3 g EPA /kg dry matter. Lambs were slaughtered after 3 weeks and digestive contents and ruminal wall samples were collected. EPA concentration in the rumen of lambs fed FD was about 50% higher than lambs fed SD or O diets. Nevertheless, the high levels of EPA in cecum and faeces of animals fed N. oceanica biomass, independently of the drying method, suggests that EPA was not completely released and absorbed in the small intestine. Furthermore, supplementation with EPA sources also affected the ruminal biohydrogenation of C18 fatty acids, mitigating the shift from the t10 biohydrogenation pathways to the t11 pathways compared to the Control diet. Overall, our results demonstrate that FD N. oceanica biomass is a natural rumen-protected source of EPA to ruminants. [ABSTRACT FROM AUTHOR]

Trans (t) fatty acids (TFA) from partially hydrogenated vegetable oils (i.e., industrial trans) have been phased out of foods in many countries due to their promotion of cardiovascular disease. This leaves ruminant‐derived foods as the main source of TFA. Unlike industrial TFA where catalytic hydrogenation yields a broad distribution of isomers, ruminant TFA are enzymatically derived and can result in enrichment of specific isomers. Comparisons between industrial and ruminant TFA have often exonerated ruminant TFA due to their lack or at times positive effects on health. At extremes, however, ruminant‐sourced foods can have either high levels of t10‐ or t11‐18:1, and when considering enriched sources, t10‐18:1 has properties similar to industrial TFA, whereas t11‐18:1 can be converted to an isomer of conjugated linoleic acid (cis(c)9,t11‐conjugated linoleic acid), both of which have potential positive health effects. Increased t10‐18:1 in meat‐producing ruminants has not been associated with negative effects on live animal production or meat quality. As such, reducing t10‐18:1 has not been of immediate concern to ruminant meat producers, as there have been no economic consequences for its enrichment; nevertheless at high levels, it can compromise the nutritional quality of beef and lamb. In anticipation that regulations regarding TFA may focus more on t10‐18:1 in beef and lamb, the present review will cover its production, analysis, biological effects, strategies for manipulation, and regulatory policy. [ABSTRACT FROM AUTHOR]

Hyperbaric storage (HS) at variable room temperature (RT) has been proposed as an alternative to refrigeration at atmospheric pressure (RF/AP) for food preservation. Little information is available regarding the effect of HS in meat products. In this study the RT/HS effect was evaluated at 100 MPa and variable RT (≈20 °C) for minced meat preservation up to 24 h, initially for one batch. A further two different batches were studied independently. Microbiological and physicochemical parameters were analyzed to assess the feasibility of RT/HS, using storage at RF/AP and variable RT/AP (≈20 °C), for comparison. A post‐hyperbaric storage (post‐HS) was also tested over 4 days at RF/AP. For the first batch the results showed that RT/HS allowed a decrease of the total aerobic mesophile value (P < 0.05) when compared to the initial sample, whereas at RF/AP and RT/AP, values increased to > 6 Log CFU g−1 after 24 h. Similarly, Enterobacteriaceae increased > 1 and > 2 Log CFU g−1 at RF/AP and RT/AP, respectively, while yeasts and molds presented similar and lower overall loads compared to the initial samples for all storage conditions, whereas RT/HS always allowed lower counts to be obtained. Regarding pH, lipid oxidation, and color parameters, RT/HS did not cause significant changes when compared to RF/AP, except after 24 h, where pH increased. The three batches presented similar results, the differences observed being mainly due to the heterogeneity of the samples. RT/HS is a potential quasi‐energetic costless alternative to RF for at least short‐term preservation of minced meat. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The use of black soldier fly (BSF) (Hermetia illucens L.) larvae fat as a lipid supplement in growing rabbit's diet was evaluated at two levels of supplementation in comparison to two levels of extruded linseed. Forty-eight weaned rabbits aged 35 days were individually housed in digestibility cages and randomly allocated to one of the four diets: Linseed-Low (30 g/kg of fat from linseed), Linseed-High (60 g/kg of fat from linseed), BSF-Low (30 g/kg of BSF fat), BSF-High (60 g/kg of BSF fat). Animals had ad libitum access to water and feed during 5 weeks, and were slaughtered at 70 days of age. In the fourth week of the trial, faeces were collected to allow the evaluation of total tract apparent digestibility (TTAD) of the diets. Mortality, dry matter (DM) intake, average daily gain, slaughter live weight, and carcass, liver, perirenal fat, scapular fat, and digestive tract weights were not affected (P > 0.05) either by fat source or fat level. The TTAD of DM, organic matter, ether extract, and gross energy were lower (P < 0.05) in the diet containing BSF fat than in linseed diets, and the decrease observed ranged between 2.3 to 3.1 percent points. With increasing the fat inclusion level, ether extract TTAD increased (P < 0.001) but the cellulose TTAD decreased (P < 0.01). Overall, diets containing BSF fat resulted in a slightly lower TTAD than linseed diets, but this seemed not to have affected growth performance and carcass yield. In conclusion, BSF fat could be considered an alternative lipid source for growing rabbit diets highlighting similar productive results to linseed. [ABSTRACT FROM AUTHOR]

Despite the recent advances in transcriptomics, gene expression studies addressing cattle´s skeletal muscle adaptations in response to compensatory growth are warranted, particularly regarding lipid metabolism due to its impact in meat sensory and nutritional traits. In the present study, in comparison to ad libitum feeding, a period of feed restriction was used in order to understand the changes in bull´s lipid metabolism and gene expression of the adipogenic and lipogenic pathways after re-alimentation. Thus, 40 young Alentejana bulls were either fed ad libitum (CG group) from 9 to 18 months of age or subjected to food restriction from 9 to 15 months of age, and fed ad libitum until 24 months of age (DG group). The intramuscular fat (IMF) and total fatty acids (FA) contents were similar between groups. The major FA (>2%) contents were similar (16:0, 16:1c9, 18:1c9 and 18:2n-6) between treatments with the exception of 18:0 content that was 15% lower in DG than in CG and 20:4n-6 that tended to be greater on DG bulls. Regarding minor FA (<2%), the DG group presented greater proportions (P<0.01) of 17:1c9, 18:1t9, 18:1t10 (, 18:1c11), 18:1c13, 18:3n-6, 22:0, 22:4n-6 and 22:6n-3 and lower (P<0.05) proportions of 20:0, 18:1t16+c14, and branched chain FA (iso-15:0, anteiso-15:0, iso-16:0 and anteiso-17:0) than the CG group. Delta-9 desaturase activity indices were consistently greater (P<0.05) in DG, when compared to the CG group. Regarding microarray analysis, differentially expressed genes between CG and DG bulls were grouped in 5 main biological functions: lipid and nucleic acid metabolisms, small molecule biochemistry, molecular transport and translational modification. Discontinuous growth down-regulated the expression of ACACB (FC (fold-change) = 1.32), FABP3 (FC = 1.45), HADHA (FC = 1.41) and SLC37A4 (FC = 1.40) genes, when compared to the CG system (FDR<0.05). In contrast, in the CG bulls, the expression of ELOVL5 (FC = 1.58) and FASN (FC = 1.71) was down-regulated when compared to DG bulls. These results were confirmed to be significant (P<0.05) in the case of ELOVL5, FASN and SLC37A4, and almost significant for FABP3 by qRT-PCR analysis. The SCD1 and SCD5 gene expressions were not found to be affected by growth path. These results contribute to the still scarce knowledge about the mechanisms involved in fatty acid metabolism during compensatory growth which have decisive role on meat quality produced in Mediterranean areas. [ABSTRACT FROM AUTHOR]

Requeijão, a Portuguese whey cheese, was selected as a case study of a highly perishable dairy product and stored at 0.1 (AP) and 100 MPa (HS) at variable room temperature (RT) (≈17-21° C) and compared with refrigeration (RT) (4° C), during two storage periods, 24 hr and 10 days. After 24 hr at AP/RT, Requeijão presented microbial counts above 6.00 log CFU/g, while after HS, total aerobic mesophiles and Enterobacteriaceae growth was inhibited. For lactic acid bacteria and yeasts and molds, HS showed an additional microbial inactivation effect, decreasing approximately 1.5 and 3.5 log CFU/g, to values below the detection limit (<1.0 log CFU/g) during the 24 hr experiment. In the second storage experiment (10 days), HS allowed to achieve counts below the detection limit, maintaining them throughout the storage period, and also the physicochemical parameters were unaffected. Thus, HS results clearly point to Requeijão shelf-life extension compared to RF. Practical applications Hyperbaric storage (HS) at room temperature (RT) is emerging as a new food preservation methodology that acts by microbial growth inhibition similarly to refrigeration. However, HS allows significant energetic costs reduction, since it only implies energy costs during compression/decompression phases (few minutes), and no additional energy is needed to control the temperature or to maintain the product under pressure for long periods as opposed to refrigeration. This is undoubtedly a great advantage for HS, since energy savings implied will greatly reduce costs throughout the storage period. As a consequence, HS also becomes an environmentally friendlier technology, with a carbon footprint estimated to be about 26-fold lower compared to refrigeration storage. This is one of the few studies concerning HS on solid foods and the first work that stored foods for longer storage periods (up to 10 days). [ABSTRACT FROM AUTHOR]

Goat dairy products are an important source of animal protein in the tropics. During the dry season, pasture scarcity leads animals to lose up to 40% of their body weight, a condition known as Seasonal Weight Loss (SWL) that is one of the major constraints in ruminant production. Breeds with high tolerance to SWL are relevant to understand the physiological responses to pasture scarcity so they could be used in programs for animal breeding. In the Canary Islands there are two dairy goat breeds with different levels of tolerance to SWL: the Palmera, susceptible to SWL; and the Majorera, tolerant to SWL. Fat is one of the milk components most affected by environmental and physiological conditions. This study hypothesises that feed-restriction affects Majorera and Palmera breeds differently, leading to different fatty acid profiles in the mammary gland and milk. An interaction between breed and feed-restriction was observed in the mammary gland. Feed-restriction was associated with an increase in oleic acid and a decrease in palmitic acid percentage in the Palmera breed whereas no differences were observed in the Majorera breed. Palmitic and oleic acids together constituted around 60% of the total fatty acids identified, which suggests that Palmera breed is more susceptible to SWL. In milk, feed-restriction affected both breeds similarly. Regarding the interaction of the breed with the treatment, we also observed similar responses in both breeds, but this influence affects only around 2% of the total fatty acids. In general, Majorera breed is more tolerant to feed-restriction. [ABSTRACT FROM PUBLISHER]

In the present study, it was hypothesized that the incorporation of fatty acids is distinct among ruminant tissues and that it could be modulated by diet composition. To test this hypothesis, fatty acid composition, including conjugated linoleic acid isomers, of the most relevant beef by-products (brain, heart, kidney, liver, pancreas and tongue) from young bulls those fed distinct silage levels was assessed. Data indicated a large variation in fatty acid profile and conjugated linoleic acid composition among edible by-products. The most abundant fatty acids were C16:0 (kidney), C18:0 (heart and liver) and C18:1c9 (brain, pancreas and tongue) followed by C20:4n-6, except in brain (C22:6n-3 predominates). Brain, as shown by principal component analysis, presents a distinct fatty acid composition compared to the other beef by-products analysed. In addition, high silage diet relative to low silage diet promoted an increase of n-3 polyunsaturated fatty acid, t11,t13 and t11,c13 conjugated linoleic acid in heart, kidney, liver and pancreas. Overall, the data suggested that beef by-products had, in general, high contents of cholesterol, saturated fatty acid and trans fatty acid, as well as high levels of conjugated linoleic acid. Therefore, from a nutritional point of view they are recommended only in small amounts as part of a balanced diet. [ABSTRACT FROM AUTHOR]

The food industry aims to produce dry fermented sausages (DFS) with high quality, but Alentejano or Iberian pork has a high price, which might jeopardize the sustainability of traditional producers. Considering this fact, the objective of this work was to evaluate the quality and acceptability of DFS made with low value pork raw material from Alentejano purebred sows and a crossbred Iberian × Duroc pigs. The nutritional fat values, microbial and sensorial quality of DFS with different diameters were assessed and the texture and fatty acids (FA) profiles were correlated with sensory attributes. Pork raw material did not influence pH, aw and microbial characteristics of both DFS, but those produced with Alentejano sows presented the highest content of polyunsaturated FA and less saturated FA. Both DFS presented satisfactory appreciations regarding sensorial quality. Practical Applications This work aims to increase knowledge about dry fermented sausage processed with an alternative crossbreed Iberian × Duroc pigs less expensive than the Iberian pigs. This alternative in traditional processing of dry fermented sausages with the maintenance of their quality and consumer acceptability will contribute to the sustainability of all traditional small meat industries and of an economic sector with great importance on the Mediterranean region. [ABSTRACT FROM AUTHOR]

BACKGROUND Tannins are polyphenolic compounds able to modify the ruminal biohydrogenation ( BH) of unsaturated fatty acids, but their activity may vary among different tannin sources. The effect of rockrose ( Cistus ladanifer) on BH has never been compared with other more common tannin sources. Tannin extracts (100 g kg−1 substrate dry matter) from chestnut ( CH), quebracho ( QB), grape seed ( GS) and rockrose ( CL) were incubated in vitro for 6 h with ruminal fluid using as substrate a feed containing 60 g kg−1 of sunflower oil. A control treatment with no added tannins was also included. RESULTS Compared with the control, GS and CL, but not CH and QB, increased ( P < 0.05) the disappearance of c9, c12-18:2 with a consequent larger production of c9, t11-18:2 and t11-18:1. However, no differences among treatments ( P > 0.05) were observed for the disappearance of c9-18:1 and c9, c12, c15-18:3. The production of 18:0 was not different ( P > 0.05) among treatments, although its proportion in the total BH products was lower ( P < 0.05) for GS than for the other treatments. CONCLUSION Condensed tannins from GS and, to a lesser extent, from CL stimulate the first steps of BH, without a clear inhibition of 18:0 production. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This study evaluated the changes of cows' milk fat fatty acids (FA) after transition from pasture to a total mixed ration (TMR) diet and back to pasture. Eight Holstein cows were used in a 52-d experiment divided into three periods. In period I (PI), cows grazed for 10 d and were supplemented with 5 kg head-1 day-1 of concentrate. On the 11th day, cows were moved to a barn and fed a TMR diet for the next 21 d (PII). On the 32nd day, cows were sent back to pasture for another 21 d (PIII) and received the same supplement of PI. Milk samples were taken on days 10 of PI and 2, 4, 7, 14 and 21 of PII and PIII. Total mixed ratio significantly increased dry matter intake and milk production and decreased milk fat content. Diet significantly affected the concentration of most FA in milk fat. Grazing pasture significantly increased the concentrations of 18:0, 18:1 c9, 18:1 t11, 18:2 c9,t11, 18:2 t11,c15, 18:3 c9,c12,c15, iso and anteiso branched-chain FA and sums of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA). Concentrations of 12:0, 14:0, 16:0, 15:0, 17:0, 18:2 c9,c12 and the sum of saturated fatty acids (SFA) significantly increased with PII diet. Most FA and FA sums took 14-21 d to stabilise in PII and only 4-7 d after transition for pasture. This evolution pattern of milk fat FA suggests that the long historical feeding regimen is a factor that impacts on the time cows take to respond to different diets by changing FA composition, probably as a result of the adaptation time of rumen microbes. [ABSTRACT FROM AUTHOR]

Information about lipid content and fatty acid (FA) composition of muskoxen (Ovibos moschatos) edible tissues is very limited in comparison to other meat sources. Thus, this work aims to present the first in-depth characterization of the FA profile of meat, subcutaneous adipose tissue and liver of muskoxen living in West Greenland. Furthermore, we aim to evaluate the effect of sex in the FA composition of these edible tissues. Samples from muscle (Longissimus dorsi), subcutaneous adipose tissue and liver were collected from female and male muskoxen, which were delivered at the butchery in Kangerlussuaq (West Greenland) during the winter hunting season. The lipid content of muscle, adipose tissue and liver averaged 284, 846 and 173 mg/g of dry tissue, respectively. This large lipid contents confirms that in late winter, when forage availability is scarce, muskoxen from West Greenland still have high fat reserves, demonstrating that they are well adapted to seasonal feed restriction. A detailed characterization of FA and dimethylacetal composition of muskoxen muscle, subcutaneous adipose tissue and liver showed that there are little differences on FA composition between sexes. Nevertheless, the 18:1cis-9 was the most abundant FA in muscle and adipose tissue, reaching 43% of total FA in muscle. The high content of 18:1cis-9 suggests that it can be selectively stored in muskoxen tissues. Regarding the nutritional composition of muskoxen edible tissues, they are not a good source of polyunsaturated FA; however, they may contribute to a higher fat intake. Information about the FA composition of muskoxen meat and liver is scarce, so this work can contribute to the characterization of the nutritional fat properties of muskoxen edible tissues and can be also useful to update food composition databases. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the physicochemical characteristics of commercially available dry fermented sausages from different origins tracing their nutritional composition and extrapolating their potential health benefits to consumers. There is a great diversity in sausages' proximal composition since each producer has their own formulation, type of manufacture and uses of pig genotype, with no differentiation regarding products' origin or diameter. The mineral contents of fermented sausages differ probably due to variations in raw materials and products' formulation as a consequence of natural mineral occurrence. In addition, the principal component analysis of fatty acid composition clearly discriminates the origin of dry fermented sausages. From the nutritional point of view, the fermented sausages provide 37-40% total fat, 13-14% saturated fat, 0.48-0.52% cholesterol as well as 0.03-0.10% α-tocopherol, which are inside of the dietary recommendations. [ABSTRACT FROM AUTHOR]

The meat from ruminants can be a valuable dietary source of rumenic acid ( c9, t11-CLA) and of n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA). Nevertheless, commonly ruminant meats present a fairly low content of both c9, t11-CLA and n-3 LC-PUFA. Most of c9, t11-CLA in meat is derived from the delta-9 desaturation of t11-18:1 catalyzed by stearoyl-CoA desaturase (SCD) and deposited in triacylglycerides (TAG). Thus, optimizing c9, t11-CLA in meat implies: a high substrate supply, a high SCD activity, and a high intramuscular fat (IMF) deposition. High rumen t11-18:1 outflow requires high forage diets which down-regulate SCD activity and IMF deposition. Conversely, as most animals are finished with cereal rich concentrate diets, the SCD activity and IMF deposition are promoted but the rumen outflow of t11-18:1 frequently is replaced by t10-18:1 ( t10-shift) which cannot be converted to CLA. Thus the occurrence of the rumen t10-shift is probably the main constraint to c9, t11-CLA enrichment in meat, as is reviewed in detail. The constrains to n-3 LC-PUFA enrichment of ruminant meat are mostly associated to the extensive rumen biohydrogenation of PUFA, the low elongation and desaturation of 18:3n-3 into n-3 LC-PUFA, and the capacity of muscle lipids to incorporate n-3 LC-PUFA. Considering the almost exclusive esterification of n-3 LC-PUFA in membrane phospholipids, the limits to n-3 LC-PUFA incorporation in muscle are discussed considering the amount of and type of available phospholipids as well as the possibility of its esterification in TAG. Simplified summary of the main drives that could limit the c9, t11-CLA deposition in meat of ruminants fed high forage or high concentrate diets. [ABSTRACT FROM AUTHOR]

The Cistus ladanifer L. shrub is a widespread species of the Mediterranean region that is available as a feed source for ruminants all the year round, constituting a source of energy and nutrients when most of the vegetation is dry. However, there is no trustworthy information about the fatty acid composition of C. ladanifer, as well as no information about the seasonal and age related changes in their fatty acid composition. Thus, we collected the aerial parts of C. ladanifer plants of two age groups [young vs. older ones (2-6 years old)] during four consecutive seasons to characterize their fatty acid composition. The fatty acid composition of C. ladanifer is dominated by saturated fatty acids including the occurrence of two methyl branched chain fatty acids (BCFA), the iso-19:0 and iso-21:0, which as far as we know were detected for the first time in shrubs. Also, we demonstrated that several labdane type compounds might interfere with the fatty acid analysis of C. ladanifer. Marked seasonal changes in BCFA and polyunsaturated fatty acids (PUFA) were found, suggesting that BCFA can replace PUFA in plant lipids at high environmental temperatures. [ABSTRACT FROM AUTHOR]

The ' trans-10 shifted' biohydrogenation pathway is frequently established in the rumen when high starch diets are fed to ruminants, resulting in the accumulation of trans-10 18:1 in ruminant products. It has been proposed that the ' trans-10 shifted' biohydrogenation pathway of α-linolenic acid generates two intermediates, the trans-10, cis-15 18:2 and trans-10, cis-12, cis-15 18:3, although none of these have been found in the rumen. We analyzed digestive contents and meat samples from two trials, where animals were fed: a compound feed diet supplemented with 8 % oil blend containing linseed oil (samples A); and a forage based diet supplemented with 6 % linseed oil (samples B). The use of the new SLB-IL111 chromatographic column allowed the detection of two different 18:2 isomers in each sample trial, which could not be resolved when the CP-Sil 88 column is used. The two 18:2 isomers were characterized by mass spectrometry using 4,4-dimethyloxazoline derivatives. However, because they were subject to higher temperatures and present different chromatographic properties compared with the fatty acid methyl esters, we also used the 'covalent adduct chemical ionization' technique to confirm the identity of both 18:2 isomers. We detected and identified the 10,15-18:2 in samples A and the 11,15-18:2 in samples B. The geometry of both isomers was tentatively assigned as trans,cis taking in account their elution order and biologic plausibility. As far as we know, this is the first time that the trans-10, cis-15 18:2 has been found in ruminant digestive contents and meat samples associated with the ' trans-10 shifted' biohydrogenation pathway of α-linolenic acid. [ABSTRACT FROM AUTHOR]

Fat tailed sheep breeds are known for their adaptation to nutritional stress, among other harsh production conditions. Damara sheep, native to Southern Africa, have recently been exported to other areas of the world, particularly Australia, aiming to produce lamb in semi-arid regions. Damaras have a unique hanging fat tail, a fat depot able to be mobilized under nutritional stress. In this article we perform an in-depth characterization of the fatty acid profiles of the fat tail in underfed and control Damara rams. Profiles were very similar between experimental groups, with the exception of palmitic acid (16:0) that was lower (P = 0.014) in underfed animals. However, the most striking result was the very high proportions of non-terminal branched chain fatty acids found in the fat tail adipose tissue, as well as the gastrocnemius muscle of Damara rams. The muscle of Dorper and Merino rams used in the same experiment did not present non-terminal branched chain fatty acids, suggesting that Damara rams have a unique lipid metabolism. Herein, we interpret this trait relating it to a higher ability of Damara sheep to digest fibrous fodder and to putative differences in the propionate metabolism by comparison to other sheep breeds. [ABSTRACT FROM AUTHOR]

Lipid metabolism in the rumen is responsible for the complex fatty acid profile of rumen outflow compared with the dietary fatty acid composition, contributing to the lipid profile of ruminant products. A method for the detailed dimethylacetal and fatty acid analysis of rumen contents was developed and applied to rumen content collected from lambs fed lucerne or concentrate based diets supplemented with soybean oil. The methodological approach developed consisted on a basic/acid direct transesterification followed by thin-layer chromatography to isolate fatty acid methyl esters from dimethylacetal, oxo- fatty acid and fatty acid dimethylesters. The dimethylacetal composition was quite similar to the fatty acid composition, presenting even-, odd- and branched-chain structures. Total and individual odd- and branched-chain dimethylacetals were mostly affected by basal diet. The presence of 18∶1 dimethylacetals indicates that biohydrogenation intermediates might be incorporated in structural microbial lipids. Moreover, medium-chain fatty acid dimethylesters were identified for the first time in the rumen content despite their concentration being relatively low. The fatty acids containing 18 carbon-chain lengths comprise the majority of the fatty acids present in the rumen content, most of them being biohydrogenation intermediates of 18∶2n−6 and 18∶3n−3. Additionally, three oxo- fatty acids were identified in rumen samples, and 16-O-18∶0 might be produced during biohydrogenation of the 18∶3n−3. [ABSTRACT FROM AUTHOR]

BACKGROUND: Consumer awareness regarding the intake of beef of organic origin is strongly associated with the beneficial outcomes to human health, the environment and animal welfare. In this paper the effects of slaughter season and muscle type on the fatty acid composition, conjugated linoleic acid (CLA) isomeric profile, total cholesterol, α-tocopherol and β-carotene contents and nutritional quality of intramuscular fat in organic beef ( n = 30) are reported for the first time. RESULTS: Organic beef showed a very low total lipid content, with seasonal changes in the levels of some fatty acids, CLA isomers, n-6/n-3 polyunsaturated fatty acid (PUFA) ratio, total cholesterol and β-carotene. In addition, differences between longissimus lumborum (relatively red) and semitendinosus (relatively white) muscles were found for many fatty acids, specific CLA contents, many CLA isomers and both PUFA/saturated fatty acid (SFA) and n-6/n-3 ratios. However, in spite of the seasonal and carcass variations, all organic meats analysed had values of beef similar to pasture-fed cattle. CONCLUSION: From a nutritional perspective, organic meat from both slaughter seasons seems to have high CLA contents, PUFA/SFA and n-6/n-3 indices within the recommended values for the human diet. The data indicate that intramuscular fat in organic meat has a high nutritional value throughout the year. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Simple Summary: Ruminant edible products have been associated with adverse health effects, due to their high saturated fatty acids and low polyunsaturated fatty acids content, resulting from the extensive biohydrogenation conducted by rumen microbiota. Cistus ladanifer condensed tannins were able to change the lamb ruminal biohydrogenation, increasing the beneficial fatty acids production. The aim of this study was to test the effect of increasing doses of C. ladanifer condensed tannins extract (0, 25, 50, 75 and 100 g/kg dry matter) on in vitro rumen fermentation and biohydrogenation. The increasing doses of condensed tannins led to a moderate decrease of volatile fatty acids production, a pronounced depression in microbial odd and branched fatty acids and of dimethyl acetals production, and a minor effect on the biohydrogenation, which indicates that microbial growth was more inhibited than fermentative and biohydrogenation activities. The ability of C. ladanifer condensed tannins extract to modulate the biohydrogenation (BH) was not observed in the present study. However, the results obtained suggest a possible adaptative response of the microbial population to stress stimuli of condensed tannins and lipid supplementation. Cistus ladanifer (rockrose) is a perennial shrub quite abundant in the Mediterranean region, and it is a rich source in secondary compounds such as condensed tannins (CTs). Condensed tannins from C. ladanifer were able to change the ruminal biohydrogenation (BH), increasing the t11–18:1 and c9,t11–18:2 production. However, the adequate conditions of the C. ladanifer CTs used to optimize the production of t11–18:1 and c9,t11–18:2 is not yet known. Thus, we tested the effect of increasing the doses of C. ladanifer CT extract (0, 25, 50, 75 and 100 g/kg dry matter (DM)) on in vitro rumen BH. Five in vitro batch incubations replicates were conducted using an oil supplemented high-concentrate substrate, incubated for 24 h with 6 mL of buffered ruminal fluid. Volatile fatty acids (VFAs) and long chain fatty acids (FA) were analyzed at 0 h and 24 h, and BH of c9–18:1, c9, c12–18:2 and c9, c12, c15–18:3, and BH products yield were computed. Increasing doses of C. ladanifer CTs led to a moderate linear decrease (p < 0.001) of the VFA production (a reduction of 27% with the highest dose compared to control). The disappearance of c9–18:1 and c9,c12–18:2 as well as the production of t11–18:1 and c9, t11:18:2 was not affected by increasing doses of C. ladanifer CTs, and only the disappearance of c9, c12, c15–18:3 suffered a mild linear decrease (a reduction of 24% with the highest dose compared to control). Nevertheless, increasing the C. ladanifer CT dose led to a strong depression of microbial odd and branched fatty acids and of dimethyl acetals production (less than 65% with the highest dose compared to control), which indicates that microbial growth was more inhibited than fermentative and biohydrogenation activities, in a possible adaptative response of microbial population to stress induced to CTs and polyunsaturated fatty acids. The ability of C. ladanifer to modulate the ruminal BH was not verified in the current in vitro experimental conditions, emphasizing the inconsistent BH response to CTs and highlighting the need to continue seeking the optimal conditions for using CTs to improve the fatty acid profile of ruminant fat. [ABSTRACT FROM AUTHOR]

Simple Summary: This research was carried out to investigate the usefulness and reliability of meat quality traits such as physicochemical properties and fatty acid profiles to discriminate between meat produced by taurine and zebu cattle, finished on pasture or grain. This approach is of utmost importance to assess the authenticity of meat products, particularly when beef is certified based on criteria such as breed and finishing system. Our results using discriminant analyses indicate that meats originating from pasture- or grain-finishing can be discriminated with high reliability, essentially on the basis of their fatty acid profile. The global distinction of meat from the two genetic groups is somewhat more difficult to achieve reliably. Still, prior knowledge of the finishing system used to produce meat from a given genetic group enhances the trustworthiness of the assignment procedure, allowing the reliable allocation of meat samples originating from Bos indicus and Bos taurus finished on pasture or grain, with fatty acid profiles being better discriminating factors than physicochemical properties. These results can be adopted as tools to be used in meat certification programs. Meat obtained under commercial conditions shows considerable variability, mostly due to genetic background and production system. In this study, meat physicochemical properties and fatty acid profiles were analysed to investigate the feasibility of using them as tools to discriminate between meats produced by different genetic groups and finishing systems. Samples of the Longissimus thoracis were collected from 160 commercial bulls of the B. taurus (n = 75) and B. indicus (n = 85) groups, finished either on pasture (n = 46) or with grain supplementation (n = 114) and analysed by standard procedures. Data were analysed by discriminant analysis using a stepwise procedure, to select the meat characteristics that better contribute to discriminate the various groups. Our results indicate that fatty acid profiles of meat had better discriminating ability than physicochemical properties, especially to identify meat from animals finished on grain or pasture. The overall discrimination of meat from different genetic groups was achieved with a slightly lower reliability. Nonetheless, our results show that reliability of allocation to genetic group can be improved if prior information on finishing system is considered. These results are of high importance because they can be incorporated as tools to assess the authenticity of beef, particularly in meat certification programs. [ABSTRACT FROM AUTHOR]

Cistus ladanifer L. is a shrub from Cistaceae family, widespread in Mediterranean countries. Fatty acids (FA) have multiple roles in plants and are involved in adaption mechanisms to environmental conditions. This work evaluated the FA content and composition of each morphological fraction of C. ladanifer (leaves, stems, flower buds, flowers and seed heads) throughout a full year. Cistus ladanifer plants were collected in southern Portugal, during four consecutive seasons (18 plants/season), and the different morphological plant fractions (leaves, stems, flower buds, flowers and seed heads) were separated. Cistus ladanifer morphological fractions showed distinct FA compositions, being possible to discriminate three groups—the leaves that showed to be dominated by saturated FA (main 20:0) and contain branched-chain FA (iso-19:0 and iso-21:0); the stems that are composed mainly by SFA (main 22:0); and the reproductive organs that showed higher contents of polyunsaturated FA (PUFA) and the 16:0 as the main SFA. The FA composition of leaves changed over seasons, with replacement of the PUFA by monounsaturated FA and branched-chain FA during hot seasons. Regarding the other C. ladanifer morphological fractions, the FA composition was more stable over seasons, suggesting that leaves are more prone to adaptations to environmental changes. [ABSTRACT FROM AUTHOR]

The addition of polyphenol extracts in ruminant diets is an effective strategy to modulate rumen microflora. The aim of this in vitro trial was to study the effects of chestnut tannin extract (CHT), vescalagin (VES) and gallic acid (GAL) on dietary fibre degradability and on the dimethyl acetals (DMA) profile and microbial community composition of rumen liquor. Four diets (basal diet; basal diet plus CHT; basal diet plus VES; basal diet plus GAL) were fermented for 24 h using ewe rumen liquor. At the end of the fermentation, the microbial communities were characterized by sequencing the 16S rRNA gene. The DMA profile was analyzed by gas chromatography. Chestnut tannin extract did not affect fibre degradability, whereas VES and GAL showed a detrimental effect. The presence of CHT, VES and GAL influenced the concentration of several DMA (i.e., 12:0, 13:0, 14:0, 15:0, 18:0 and 18:1 trans-11), whereas the composition of the microbial community was marginally affected. The inclusion of CHT led to the enrichment of the genera Anaerovibrio, Bibersteinia, Escherichia/Shigella, Pseudobutyrivibrio and Streptococcus. The results of this study support the hypothesis that the activity of CHT is due to the synergistic effect of all components rather than the property of a single component. [ABSTRACT FROM AUTHOR]