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1.
Tree Physiol ; 43(8): 1290-1306, 2023 08 11.
Article in English | MEDLINE | ID: mdl-36930058

ABSTRACT

Drought is projected to occur more frequently and intensely in the coming decades, and the extent to which it will affect forest functioning will depend on species-specific responses to water stress. Aiming to understand the hydraulic traits and water dynamics behind water-saver and water-spender strategies in response to drought and recovery, we conducted a pot experiment with two species with contrasting physiological strategies, Scots pine (Pinus sylvestris L.) and Portuguese oak (Quercus faginea L.). We applied two cycles of soil drying and recovery and irrigated with isotopically different water to track fast changes in soil and stem water pools, while continuously measuring physiological status and xylem water content from twigs. Our results provide evidence for a tight link between the leaf-level response and the water uptake and storage patterns in the stem. The water-saver strategy of pines prevented stem dehydration by rapidly closing stomata which limited their water uptake during the early stages of drought and recovery. Conversely, oaks showed a less conservative strategy, maintaining transpiration and physiological activity under dry soil conditions, and consequently becoming more dehydrated at the stem level. We interpreted this dehydration as the release of water from elastic storage tissues as no major loss of hydraulic conductance occurred for this species. After soil rewetting, pines recovered pre-drought leaf water potential rapidly, but it took longer to replace the water from conductive tissues (slower labeling speed). In contrast, water-spender oaks were able to quickly replace xylem water during recovery (fast labeling speed), but it took longer to refill stem storage tissues, and hence to recover pre-drought leaf water potential. These different patterns in sap flow rates, speed and duration of the labeling reflected a combination of water-use and storage traits, linked to the leaf-level strategies in response to drought and recovery.


Subject(s)
Pinus sylvestris , Quercus , Dehydration , Droughts , Biological Transport , Desiccation , Soil
2.
Meat Sci ; 198: 109098, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36681060

ABSTRACT

Two groups of 8 individually housed young crossbred-bulls, in the finishing period, were used to test the effect of a Total Mixed Ration diet with high forage content (54% DM), low starch content (14% DM), supplemented with sunflower seeds (10% DM) (HFS) on growth performance, carcass and meat quality, fatty acid profile and carbon footprint, with reference to a conventional concentrate-based (90% DM) (Control) diet. The experiment lasted 64 days before slaughter. During the experiment, feed intake was monitored daily and live weight every 14 days. Individual CH4 emissions were assessed at 16-days intervals, using a GreenFeed for Large Animal unit. Feed intake and feed conversion ratio were higher for HFS diet, but average daily weight gain and feeding costs were similar for the two diets. Dressing percentage was reduced with HFS diet. The HFS increased redness, yellowness and Chroma of subcutaneous fat, but did not compromise commercial value of the carcasses. Meat colour, shear force, or sensory parameters were not affected by diet. The HFS diet allowed a healthier FA profile, due to the higher proportions of 18:3n-3, t11-18:1 and c9,t11-18:2 and the lower proportion of t10-18:1. The HFS diet did not reduce the carbon footprint in the finishing period of young bulls, due to increased digestive CH4 emissions. The results of this experiment showed that the HFS diet can be an alternative to the conventional diets used in finishing young-bulls. Although it may result in a slight reduction in animal performance, it has a strong impact on reducing dependence on inputs from outside the farm.


Subject(s)
Greenhouse Gases , Animals , Cattle , Male , Animal Feed/analysis , Diet/veterinary , Meat , Dietary Supplements
3.
Meat Sci ; 188: 108782, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35303657

ABSTRACT

Thirty-two bulls were assigned to four total mixed biodiverse haylage-based diets to evaluate the effects of partial substitution of grains by agroindustrial byproducts, sunflower seeds (SS) supplementation and haylage level on growth, in vitro methane production and carcass and meat quality. Dietary treatments included a grain-based diet with 30% grain and haylage:concentrate ratio (H:C) of 60:40 (DM basis) (MCe); a by-product-based diet where 50% of the grain was substituted for by-products (H:C, 60:40) (MBp); a byproducts diet with 10% sunflower seed and 90% (DM) MBp (H:C, 54:46) (MBpSS); and a byproducts, SS diet with increased haylage (H:C, 67.5:32.5) (HBpSS). Dry matter intake and growth rate were lower in HBpSS, but feed conversion ratio was unaffected by diet. In vitro methane emissions were reduced by SS. Meat colour and shear force were similar among diets. Lipid oxidation in cooked meat was reduced and fatty acid composition was improved with SS. Biodiverse haylage-based diets may be a viable option for finishing bulls.


Subject(s)
Animal Feed , Helianthus , Animal Feed/analysis , Animals , Cattle , Diet/veterinary , Dietary Supplements , Edible Grain , Male , Meat , Methane
4.
Sci Rep ; 11(1): 21878, 2021 11 08.
Article in English | MEDLINE | ID: mdl-34750444

ABSTRACT

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.


Subject(s)
Eicosapentaenoic Acid/metabolism , Rumen/metabolism , Sheep, Domestic/metabolism , Stramenopiles/chemistry , Animal Feed/analysis , Animals , Biomass , Diet/veterinary , Dietary Supplements , Digestion , Fatty Acids/metabolism , Freeze Drying , Gastrointestinal Microbiome , Intestinal Absorption , Male , Microalgae/chemistry , Microalgae/ultrastructure , Microscopy, Electron, Scanning , Rumen/microbiology , Sheep, Domestic/microbiology , Stramenopiles/ultrastructure
5.
Meat Sci ; 168: 108191, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32450454

ABSTRACT

Growth performance, carcass and meat quality of 16 Alentejana bulls fed for 90 days with a conventional cereal-based (Control) or a high-fibre and low-starch (HFLS) diet were studied. The HFLS diet included 20% alfalfa hay, 4.8% soybean oil, 6% soybean hulls, 6% dehydrated citrus and 6% sugar beet pulps in substitution of grain. Ryegrass hay was offered to a maximum of 20% of total intake in both diets. Bulls were individually housed, weighed every 14 days, and feed intake was registered daily. Average daily weight gain, dry matter intake, carcass and most meat quality traits were not affected by the diet (P > .05). Feeding an HFLS diet, therefore, can improve beef fatty acid profiles without negatively impacting animal performance or meat quality.


Subject(s)
Animal Feed/analysis , Dietary Fiber , Red Meat/analysis , Starch , Animal Nutritional Physiological Phenomena , Animals , Cattle/growth & development , Diet/veterinary , Fatty Acids/analysis , Male
6.
Meat Sci ; 164: 108092, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32172003

ABSTRACT

The aim of this study was to evaluate the effect of the dietary inclusion of Cistus ladanifer L. and vegetable oils on intramuscular fat composition, muscle antioxidant status and lipid oxidative stability, and explore the mechanism by which dietary Cistus ladanifer limits the lipid oxidation. Lambs were assigned 9 diets, corresponding to 3 levels of Cistus ladanifer (50, 100 and 200 g/kg DM) and 3 levels of oil (0, 40 and 80 g/kg DM). Oil supplementation increased highly peroxidizable fatty acid content and the peroxidizability index (P < .05). Muscle phenolic content, reducing ability and radical scavenging ability were not affected by Cistus ladanifer (P > .05). The highest level of Cistus ladanifer enhanced muscle resistance to lipid oxidation (P = .006) and increased α-tocopherol content (P = .005), reducing meat lipid oxidation over 7 days of storage (P < .001). Results showed that Cistus ladanifer has a protective effect against lipid oxidation through increasing α-tocopherol concentration in the muscle.


Subject(s)
Diet/veterinary , Red Meat/analysis , alpha-Tocopherol/analysis , Animal Feed/analysis , Animals , Antioxidants/analysis , Cistus , Fatty Acids, Unsaturated/analysis , Linseed Oil , Lipid Metabolism , Male , Plant Oils , Random Allocation , Sheep, Domestic
7.
Trop Anim Health Prod ; 52(4): 1623-1630, 2020 Jul.
Article in English | MEDLINE | ID: mdl-31838719

ABSTRACT

The aim of this study was to evaluate the effect of partial or total replacement of Tifton 85 hay with cassava foliage hay and/or spineless cactus on the weight gain, body measurements, ingestive behaviour, and parasite infection of confined sheep. Thirty-five non-castrated male lambs with no defined breed were housed in individual pens for 90 days. Five treatments in a complete mixture were offered twice a day: Tifton hay (TH), cassava foliage hay (CFH), Tifton hay + cassava foliage hay (TH + CFH), Tifton hay + spineless cactus (TH + SC), and cassava foliage hay + spineless cactus (CFH + SC). The data were evaluated by analysis of variance and Tukey's test at 5% probability. The dry matter and crude protein intake were higher in sheep fed CFH and CFH + SC than sheep fed TH. Animals fed TH + SC presented a higher average daily gain (0.215 g) than sheep fed TH (0.125 g). The addition of spineless cactus to the diet with Tifton hay increased the feed efficiency by approximately 100% but did not affect the faecal egg count/g. The use of cassava foliage hay and its association with spineless cactus is recommended for the replacement of Tifton 85 hay in the diet of confined sheep.


Subject(s)
Animal Feed/analysis , Cactaceae , Diet/veterinary , Manihot , Sheep, Domestic/growth & development , Animal Nutritional Physiological Phenomena , Animals , Feeding Behavior , Male , Parasite Egg Count , Red Meat , Sheep , Sheep, Domestic/parasitology , Weight Gain
8.
Meat Sci ; 160: 107945, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31627117

ABSTRACT

Thirty-six lambs were used to evaluate the effect of three levels of Cistus ladanifer condensed tannins (CT; 0, 1.25 and 2.5%) and two ways of CT supply (C. ladanifer aerial parts and C. ladanifer CT extract) on lamb growth performance, carcass composition, meat quality and FA composition of intramuscular and subcutaneous fat. The basal diet was composed of dehydrated lucerne supplemented with 60 g/kg of soybean oil. The highest amount of CT (2.5%) had detrimental effects on growth performance, particularly when the aerial part of C. ladanifer was used. Conversely, 1.25% CT in diets did not affect growth performance and meat quality, and inclusion of C. ladanifer CT extract in diet at this level increased t11-18:1, but not c9,t11-18:2 content in fat. Feeding C. ladanifer CT extract might be a good approach for enhancing the nutritional value of ruminant fat, but further studies are needed to ensure upregulation of endogenous synthesis of c9,t11-18:2.


Subject(s)
Cistus , Diet/veterinary , Red Meat/analysis , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Fatty Acids/analysis , Male , Plant Components, Aerial , Plant Extracts , Proanthocyanidins , Sheep, Domestic/growth & development
9.
Meat Sci ; 161: 107964, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31683223

ABSTRACT

Thirty-two crossbred Merino branco male lambs were randomly allocated to eight diets, combining two forms of alfalfa presentation (chopped or ground), with four barley grain levels (0%, 11.2%, 21.3% and 33% dry matter (DM)), balanced by low starch agro-industrial by-products (LSBP). The diets were supplemented with 6% soybean oil and included 40% of alfalfa in DM. The lambs were individually housed and the trial lasted six weeks. Intake of DM, average daily weight gain (ADG) and carcass weight were higher with ground alfalfa (P < 0.01). Replacing barley grain by LSBP reduced linearly DM intake and ADG (P < 0.001) but increased meat tenderness (P = 0.046). Regardless of the treatments, meat showed a healthy biohydrogenation fatty acid (FA) profile, with high proportions of t11-18:1, c9,t11-18:2 and a t10-18:1/t11-18:1 ratio clearly below 1. The reduction of barley in diet had a moderate positive impact on meat FA composition, decreasing t10-18:1, which was enhanced by the increase of forage particle size.


Subject(s)
Animal Feed/analysis , Feeding Behavior/physiology , Food Quality , Medicago sativa/chemistry , Particle Size , Rumen/physiology , Starch/administration & dosage , Animal Nutritional Physiological Phenomena/physiology , Animals , Behavior, Animal/physiology , Diet/methods , Male , Red Meat , Sheep
10.
PLoS One ; 14(9): e0221996, 2019.
Article in English | MEDLINE | ID: mdl-31490993

ABSTRACT

This study investigated the associations between abundance of rumen ciliate protozoa and the proportion of the main bioactive fatty acids related to rumen biohydrogenation, as 18:0, t10-18:1, t11-18:1, c9,t11-18:2, 18:3n-3 and 18:2 n-6, in rumen and meat of growing lambs, using data derived from 3 production experiments. A global correlation analysis and a linear regression analysis considering the effect of the experiment were performed. Ten of the 86 lambs involved in the experiments did not present ciliate cells in rumen liquor and the remaining lambs presented an average of 1.35 × 106ciliates / ml rumen liquor. From the nine genera of ciliates identified, Entodinium was the most abundant, averaging 1.17 × 106 cells / ml of rumen liquor. A large variation among lambs was observed for both rumen concentration and community structure of ciliates. Rumen t11-18:1 (P < 0.001) and meat deposition of t11-18:1 (P < 0.001) and of c9,t11-18:2 (P < 0.001) increased linearly with total ciliates, whereas the t10/t11 ratio in rumen (P = 0.002) and in meat (P = 0.036) decreased linearly. Entodiniomorphids seems to be strongly related with meat deposition oft11-18:1 and c9,t11-18:2 and with the reduction of the trans-10 shifted pathway. Completeness of RBH decreased linearly with Holotrichs (P = 0.029), Entodiniomorphids (P = 0.029), Isotricha (P = 0.011) and Epidinium (P = 0.027) abundances. Rumen 18:0 also decreased linearly with increasing counts of total ciliates (P = 0.015), Holotrichs (P = 0.020), Entodiniomorphids (P = 0.010) and Isotricha (P = 0.014). Rumen protozoa were positively linked with the deposition of healthy bioactive FA and simultaneously negatively associated with the occurrence of trans-10 shift.


Subject(s)
Ciliophora/metabolism , Fatty Acids/metabolism , Meat , Rumen/microbiology , Sheep/microbiology , Animals , Diet , Hydrogenation , Muscles/metabolism , Muscles/microbiology , Regression Analysis
11.
Meat Sci ; 147: 28-36, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30196198

ABSTRACT

With this trial we have tested the effects of structural and chemical composition of neutral detergent fibre (NDF) of the diet on lamb fatty acid composition of meat and subcutaneous fat. Twenty lambs, were fed complete diets with low starch and similar NDF content of different origin (ground alfalfa or soybean hulls). Animal performance and product quality were not affected by treatments. Rumen pH increased and parakeratosis intensity decreased with the level of alfalfa in the diet. Increasing the alfalfa proportion in the diet decreased t10-18:1 (P = .023), increased t11-18:1 (P = .003) and decreased the t10/t11 ratio according to a quadratic pattern (P = .020). Chemical composition and structure of the diet's fibrous fraction influenced the BI pattern of the final product. Forty percent of alfalfa in diet reduced the severity of t10-shift, but for its full resolution, other factors should be considered including forage particle size and buffering capacity of the diet.


Subject(s)
Animal Feed/analysis , Dietary Fiber , Red Meat/analysis , Sheep, Domestic/growth & development , Animals , Diet/veterinary , Fatty Acids/analysis , Male , Medicago sativa , Parakeratosis/veterinary , Rumen/chemistry , Glycine max , Subcutaneous Fat
12.
Food Sci Technol Int ; 23(3): 209-221, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28359203

ABSTRACT

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 C18:1 c9 (brain, pancreas and tongue) followed by C20:4 n-6, except in brain (C22:6 n-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.


Subject(s)
Animal Feed , Cattle , Diet/veterinary , Fatty Acids/analysis , Meat/analysis , Silage , Animals , Cholesterol/analysis , Fatty Acids, Omega-3/analysis , Linoleic Acids, Conjugated/analysis , Linoleic Acids, Conjugated/chemistry , Male , Trans Fatty Acids/analysis
13.
Meat Sci ; 123: 166-172, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27744146

ABSTRACT

Forty lambs were fed one of four diets supplemented with a linseed and sunflower oil blend but differing in starch level (mid, ≈35 vs. high, ≈50%) and starch rumen degradability (mid, ≈70 vs. high, ≈80%). The effects of diet on growth, carcass traits and meat fatty acid (FA) composition, with emphasis on biohydrogenation intermediates were evaluated. Lambs stayed on trial for 5weeks until slaughter. Treatment had no effect on animal performance and carcass traits. High-degradability diets decreased (P=0.04) meat shear force compared with mid-degradability diets. Lipid content of meat was unaffected by the diet. Mid-starch diets increased (P<0.05) the saturated FA and cis-MUFA but decreased (P<0.05) the trans-MUFA, particularly the t10-18:1, when compared with high-starch diets. The t11-18:1 (0.7% of total FA) and c9,t11-18:2 (<0.3%) remained low and the 18:3n-3 remained high (1.74%) and unaffected by diet.


Subject(s)
Animal Feed/analysis , Diet/veterinary , Fatty Acids/analysis , Red Meat/analysis , Rumen/metabolism , Starch/administration & dosage , Animals , Food Analysis , Food Quality , Linseed Oil/administration & dosage , Plant Oils/administration & dosage , Sheep, Domestic , Sunflower Oil
14.
J Dairy Sci ; 99(2): 1173-1182, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26686729

ABSTRACT

This study evaluates the effect of the replacement of cereals by dried citrus pulp (DCP) in diets supplemented with 5% of soybean oil, on ewe milk yield and composition, including milk fatty acid (FA). Four Serra da Estrela multiparous ewes in the second month of lactation were used in a double 2×2 Latin square design. Ewes were individually penned and milked twice a day with an 8-h interval. Each experimental period included 14 d of diet adaptation followed by 5d of measurements and sampling. The 2 diets included on dry matter basis 450 g/kg of corn silage and 550 g/kg of either a soybean oil-supplemented concentrate meal containing barley and maize (cereal) or dried citrus pulp (DCP; citrus). Feed was offered ad libitum, considering 10% of orts, and intake was measured daily. Milk yield was higher and dry matter intake tended to be higher with the citrus diet. Milk composition and technological properties for cheese production were not affected by treatments, except for lactose, which was lower with the citrus diet. Replacement of cereals by DCP resulted in a 3-percentage-point decrease of both 18:0 and cis-9-18:1 that were mostly compensated by the 4.19- and 1.68-percentage-point increases of trans-11-18:1 and cis-9,trans-11-18:2, respectively. The intake of C18 FA tended to increase with the citrus diet compared with the cereal diet, but the apparent transfer of 18:2n-6 and of 18:3n-3 did not differ between diets. The milk output of C18 FA increased with the citrus compared with the cereal diet, mostly due to the increase of trans-11-18:1 and cis-9,trans-11-18:2 because the daily milk output of 18:0, trans-10-18:1, cis-9-18:1, 18:2n-6 and 18:3n-3 did not differ between diets. Replacing cereals with DCP in an oil-supplemented diet resulted in a selective increase of trans-11-18:1 and cis-9,trans-11-18:2 in milk, with no major effect on other biohydrogenation intermediates.


Subject(s)
Citrus , Diet/veterinary , Linoleic Acids, Conjugated/analysis , Milk/chemistry , Oleic Acids/analysis , Sheep/metabolism , Animals , Dietary Fats, Unsaturated/pharmacology , Dietary Supplements , Edible Grain , Fatty Acids/pharmacology , Female , Fruit , Hordeum , Lactation/drug effects , Silage/analysis , Soybean Oil/administration & dosage , Zea mays
15.
Environ Sci Pollut Res Int ; 22(20): 15479-94, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26006069

ABSTRACT

Toxic effects of copper (Cu) were analyzed in young plants of Inga subnuda subs. luschnathiana, a species that is highly tolerant to flooding and found in Brazil in wetlands contaminated with Cu. Plants were cultivated in fully nutritive solution, containing different concentrations of Cu (from 0.08 µmol to 0.47 mmol L(-1)). Symptoms of Cu toxicity were observed in both leaves and roots of plants cultivated from 0.16 mmol Cu L(-1). In the leaves, Cu clearly induced alterations in the thickness of the epidermis, mesophyll, palisade parenchyma, and intercellular space of the lacunose parenchyma. Also, this metal induced disorganization in thylakoid membranes, internal and external membrane rupture in chloroplasts, mitochondrial alterations, and electrodense material deposition in vacuoles of the parenchyma and cell walls. The starch grains disappeared; however, an increase of plastoglobule numbers was observed according to Cu toxicity. In the roots, destruction of the epidermis, reduction of the intercellular space, and modifications in the format of initial cells of the external cortex were evident. Cell walls and endoderm had been broken, invaginations of tonoplast and vacuole retractions were found, and, again, electrodense material was observed in these sites. Mineral nutrient analysis revealed higher Cu accumulation in the roots and greater macro- and micronutrients accumulation into shoots. Thus, root morphological and ultrastructural changes induced differential nutrients uptake and their translocations from root toward shoots, and this was related to membrane and endoderm ruptures caused by Cu toxicity.


Subject(s)
Copper/toxicity , Fabaceae/drug effects , Water Pollutants, Chemical/toxicity , Brazil , Calcium Oxalate/metabolism , Cell Wall/metabolism , Cell Wall/ultrastructure , Copper/analysis , Fabaceae/metabolism , Fabaceae/ultrastructure , Plant Leaves/drug effects , Plant Leaves/metabolism , Plant Leaves/ultrastructure , Plant Roots/drug effects , Plant Roots/metabolism , Plant Roots/ultrastructure , Thylakoids/metabolism , Water Pollutants, Chemical/analysis , Wetlands
16.
PLoS One ; 8(3): e58386, 2013.
Article in English | MEDLINE | ID: mdl-23484024

ABSTRACT

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.


Subject(s)
Fatty Acids/analysis , Isobutyrates/analysis , Lipid Metabolism/physiology , Rumen/chemistry , Sheep/metabolism , Animal Feed , Animals , Chromatography, Thin Layer , Dietary Supplements , Medicago sativa , Sheep/physiology , Soybean Oil
17.
Meat Sci ; 93(3): 405-12, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23273443

ABSTRACT

This study assessed the effect of breed and diet on carcass composition, particularly fat partitioning, and meat quality in young bulls. An experiment with forty young bulls from two phylogenetically distant Portuguese bovine breeds, Alentejana and Barrosã, fed two diets with different maize silage to concentrate ratios, but isoenergetic and isonitrogenous, was carried out until the animals reached 18 months of age. In the longissimus lumborum muscle, Barrosã bulls fed the low silage diet had the highest intramuscular fat (IMF) content. Bulls fed the low silage diet also had the highest IMF content in the semitendinosus muscle. Diet determined the proportions of total visceral fat and individual fat depots. Under these experimental conditions, it was shown that the genetic background is a major determinant of carcass composition and meat quality, and that the dietary differences studied had limited effect on carcass composition.


Subject(s)
Adipose Tissue/metabolism , Breeding , Diet , Meat/analysis , Muscle, Skeletal/metabolism , Silage , Zea mays , Animals , Body Composition , Cattle , Dietary Fats/metabolism , Energy Intake , Intra-Abdominal Fat/metabolism , Male , Meat/standards , Nitrogen/administration & dosage
18.
Meat Sci ; 92(4): 841-7, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22885021

ABSTRACT

Thirty-six Merino Branco lambs were assigned to six dietary treatments: control diet (C) consisting of 90% dehydrated lucerne and 10% wheat bran; C with 6% of oil blend (CO); C with 2.5% of grape seed extract (GS); GS with 6% of oil blend (GSO); C with 25% of Cistus ladanifer (CL), and CL with 6% of oil blend (CLO). Meat lipid and colour stability was then evaluated during 7 days of storage. The effect of inclusion of grape seed extract and C. ladanifer in diets on meat sensory properties was also evaluated. Meat antioxidant potential, determined after oxidation induction by a ferrous/hydrogen peroxide system, decreased with oil supplementation (P<0.001), but inclusion of grape seed extract and C. ladanifer in diets protected the meat against lipid oxidation (P=0.036). Meat colour was not affected by diets. Inclusion of grape seed extract and C. ladanifer in diets did not change the sensory properties of meat.


Subject(s)
Antioxidants/metabolism , Diet/veterinary , Fatty Acids, Unsaturated/metabolism , Food Quality , Meat/analysis , Muscle, Skeletal/metabolism , Sheep, Domestic/metabolism , Adipose Tissue, White/chemistry , Adipose Tissue, White/growth & development , Adipose Tissue, White/metabolism , Animals , Animals, Inbred Strains , Antioxidants/administration & dosage , Antioxidants/analysis , Cistus/chemistry , Diet/adverse effects , Fatty Acids, Unsaturated/adverse effects , Food Storage , Grape Seed Extract/chemistry , Grape Seed Extract/metabolism , Humans , Linseed Oil/adverse effects , Linseed Oil/metabolism , Lipid Peroxidation , Muscle, Skeletal/chemistry , Muscle, Skeletal/growth & development , Pigmentation , Plant Leaves/chemistry , Plant Oils/adverse effects , Plant Oils/metabolism , Plant Stems/chemistry , Portugal , Sensation , Sheep, Domestic/growth & development , Sunflower Oil
19.
J Agric Food Chem ; 58(19): 10710-21, 2010 Oct 13.
Article in English | MEDLINE | ID: mdl-20831248

ABSTRACT

Thirty-six lambs were used in a 6 week experiment to evaluate the effect of vegetable oil blend supplementation (0 vs 60 g/kg of dry matter (DM)) and two dietary condensed tannin sources, grape seed extract (0 vs 25 g/kg of DM) and Cistus ladanifer L. (0 vs 250 g/kg of DM), on fatty acid (FA) composition of abomasal digesta and intramuscular polar and neutral lipids. Grape seed extract did not affect the FA profile of abomasal digesta or muscle lipid fractions. C. ladanifer had a minor effect in lambs fed diets with no oil but greatly changed the abomasal and muscle FA profiles in oil-supplemented lambs. It decreased 18:0 and increased 18:1 trans-11 in abomasal digesta and increased 18:1 trans-11 and 18:2 cis-9,trans-11 (P = 0.062) in muscle neutral lipids, resulting in an important enrichment of meat 18:2 cis-9,trans-11 when compared to other oil-supplemented diets (19.2 vs 41.7 mg/100 g of muscle).


Subject(s)
Abomasum/metabolism , Cistus/chemistry , Fatty Acids/analysis , Grape Seed Extract/administration & dosage , Plant Oils/administration & dosage , Sheep/metabolism , Adipose Tissue/chemistry , Animals , Diet , Dietary Supplements , Digestion , Fatty Acids/administration & dosage , Male , Muscles/chemistry , Plant Leaves/chemistry , Plant Stems/chemistry , Proanthocyanidins/administration & dosage , Sheep/growth & development
20.
Meat Sci ; 83(3): 499-505, 2009 Nov.
Article in English | MEDLINE | ID: mdl-20416670

ABSTRACT

The effect of stepwise replacement of dietary sunflower oil (SO) with linseed oil (LO) on carcass composition, meat colour and fatty acid (FA) composition of intramuscular lipids of lamb meat was investigated. Thirty-six lambs were fed one of four diets consisting of pellets of lucerne with oil (60g/kg): the diet varied in the composition of oil added and were: 100% SO; 66.6% SO plus 33.3% LO; 33.3% SO plus 66.6% LO and 100% LO. The experimental period was 7weeks. Live slaughter weight, hot carcass weight and intermuscular fat percentage of chump and shoulder increased linearly with replacement of SO by LO. Total FA content of longissimus dorsi muscle and polar and neutral lipids were not affected by the treatments. Replacement of SO with LO increased the content of 18:3n-3 and total n-3 long chain (⩾C(20)) PUFA (LC-PUFA) and decreased the 18:2n-6, total n-6 LC-PUFA and 18:2 cis-9, trans-11 in meat lipids. Maximum CLA concentration (42.9mg/100g fresh muscle) was observed with 100% of SO, decreasing linearly by SO with LO replacement. Maximum n-3 LC-PUFA was predicted to be 27mg/100g of fresh muscle at 78% of SO with LO replacement. Considering both CLA and n-3 LC-PUFA, the maximum levels were estimated to be reached at 52% of replacement of SO with LO. The utilization of blends of SO and LO is a good approach for obtaining lamb meat enriched with both CLA and n-3 LC-PUFA.

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