Effects of sunflower oil infusions of Asparagopsis taxiformis on in vitro ruminal methane production and biohydrogenation of polyunsaturated fatty acids.

Asparagopsis taxiformis inhibits ruminal methane (CH4) production due to its bromoform (CHBr3) content. The immersion of A. taxiformis in edible vegetable oils allows the extraction and stabilization of the highly volatile CHBr3 in the oil phase. The objectives of this study were to explore the effects of adding sunflower oils with increasing concentrations of CHBr3 on in vitro ruminal methanogenesis and biohydrogenation. Five batches of 48-h in vitro incubations were performed in 14 fermentation bottles, using rumen inocula collected shortly after the slaughter of young crossbred bulls and 1 g of dry matter (DM) from a total diet of mixed feed without added oil (control) or with 60 µL of sunflower oil per gram of DM as the substrate. The treatments were the CHBr3 content in the oil added: 0 µg (B0), 25 µg (B25), 50 µg (B50), 75 µg (B75), 100 µg (B100), and 150 µg (B150) of CHBr3 per gram of substrate DM. Organic matter (OM) degradability, total gas, CH4, volatile fatty acids (VFA), long-chain fatty acids, and dimethyl acetals (DMA) were analyzed at the end of each incubation. Data were analyzed with a model considering the treatments as the fixed effect and the run as a random block and using orthogonal contrasts. Degradability of OM was higher in the control group and was unaffected by CHBr3 concentration. Total gas production per gram of degraded OM was unaffected by treatments and averaged 205 ± 29.8 mL/g. Methane (mL) production decreased linearly with increasing CHBr3 concentrations, with 33%, 47%, and 87% reductions for B75, B100, and B150, respectively. Total VFA concentration was unaffected by oil inclusion but was reduced by 20% in CHBr3-containing treatments, although without any dose-response pattern. The molar percentage of acetate decreased linearly, whereas propionate and butyrate increased linearly with the increasing CHBr3 dosage. Including oil in the diet decreased the branched-chain fatty acids and DMA content. Increasing CHBr3 concentrations did not affect branched-chain fatty acids, but linearly increased most of the identified DMA. Adding oil to the control diet increased the 18:2n-6, whereas increasing the concentration of CHBr3 had no effect on 18:2n-6 but decreased linearly the 18:0 and increased the trans-18:1 isomers. The results obtained provide evidence that oil immersions of A. taxiformis can successfully inhibit ruminal production of CH4 in vitro at doses of 100 and 150 µg/g DM, and simultaneously modulate biohydrogenation.

Bovine oocyte membrane permeability and cryosurvival: Effects of different cryoprotectants and calcium in the vitrification media.

The cryopreservation process must be improved to enhance oocyte cryosurvival and functionality. Two protocols with different cryoprotectants (CPAs), containing either ethylene glycol (EG), dimethyl sulfoxide (DMSO) and sucrose (EGDMSO) or 1,2-propanediol and sucrose (PrOH) were evaluated. In both protocols, calcium (Ca2+) free or -containing base media were tested. Oocytes were subjected to vitrification or only exposed to CPAs without immersion in liquid nitrogen. Oocyte's viability, cortical granules location and competence for development after fertilization were assessed. Finally, fatty acid composition and membrane permeability of oocytes exposed to CPAs were analyzed. Independently of Ca2+ concentration in the vitrification media, the development rates were higher in oocytes vitrified with EGDMSO protocols (p = 0.0005). After warming, higher cleavage rates were obtained in EGDMSO + Ca2+ compared to the PrOH without Ca2+ protocol (p = 0.02). Oocytes exposed to PrOH without Ca2+ presented lower cleavage rates compared to control (p = 0.04). An enhanced premature zona hardening in vitrified oocytes as well as lower concentrations of the fatty acids c11:18:1 and 20:4n-6 in cumulus oocyte complexes exposed to PrOH protocols were identified. The oocytes minimum volume and permeability were affected by the exposure to PrOH and Ca2+ (p ≤ 0.007). In conclusion, the most effective protocol for bovine oocytes cryopreservation combines EG and DMSO, independently of Ca2+ concentration in the media. A higher toxicity and an incomplete depletion of water during PrOH loading may hamper oocyte viability. The type of CPAs and Ca2+ interfered differentially on oocyte pathways to functionality, and this should be considered when choosing a cryopreservation protocol.

Effect of reduced dietary protein and supplementation with a docosahexaenoic acid product on broiler performance and meat quality.

1. Chicken breast meat is a lean meat due to its low content of intramuscular fat (IMF) resulting in an overall lower acceptability by consumers due to a decrease in juiciness, flavour and increased chewiness. Recently, studies performed in pigs suggested the possibility of increasing IMF by decreasing dietary crude protein (CP) content, an effect possibly mediated through an increased lipogenesis. 2. Dietary supplementation with lipids rich in omega 3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) may modulate an increase in the content of these fatty acids in meat from monogastric animals and, thus, promote the daily intake of n-3 LC-PUFA by humans. 3. LC-PUFA are very susceptible to oxidation, resulting in off-flavours that affect meat quality and consumers' acceptability. 4. This trial was conducted to assess the effect of reducing dietary CP, from 21% to 17%, on chicken's meat IMF content and, simultaneously, to evaluate if a complementary supplementation with a proprietary n-3 LC-PUFA source (DHA Gold™) could improve meat quality. These effects were assessed by measuring productive performance and meat quality, oxidative stability, sensory traits and fatty acid profile. 5. A reduction in CP content of broiler diets, from 21% to 17%, balanced for lysine, improved performance while it was not sufficient to increase IMF content in chicken meat. In contrast, DHA Gold™ supplementation had a positive impact both in broiler productive parameters and in meat fatty acid profile. 6. In addition, incorporation of 7.4% of DHA Gold™ in the diet promoted carcass yield but negatively affected chicken meat acceptability by consumers, due to a decrease of meat oxidative stability. 7. Overall the data suggest that neither a dietary supplementation with DHA Gold™ nor a reduction in CP have a direct positive effect in the levels of IMF present in broiler meat.

Nutritional value of meat lipid fraction obtained from mallard duck (Anas platyrhynchos) reared in semiextensive conditions for hunting purposes.

The mallard duck or wild duck (Anas platyrhynchos) is the world's most widespread and numerous dabbling duck, being traditionally hunted across many countries in Europe and North America. This study aims to provide a detailed characterization of mallard duck's meat lipid fraction obtained from farmed specimens, reared for hunting purposes, under semiextensive conditions. The mallard's duck meat total lipid content averaged 2.0 and 4.26 g/100 g of fresh meat in breast and leg meat portions, and its meat comprised 23 individual fatty acids (FA) and 3 dimethylacetals (DMA), independently of the sex or meat portion. The oleic (C18:1 cis-9), palmitic (C16:0), stearic (C18:0), linoleic (C18:2n-6), arachidonic (C20:4n-6), palmitoleic (C16:1 cis-9), and cis-vaccenic (C18:1 cis-11) acids were the predominant FA (representing >1% of total fatty acids in both breast and leg meat portions and independently of the sex), and together, these 7 fatty acids were accountable for 92.4 to 96.5% of total FA plus DMA in mallard duck meat. The monounsaturated, saturated and polyunsaturated fatty acids were accountable for 40.4, 35.0, and 21.0% of total FA plus DMA in breast and 54.6, 38.7, and 5.7% of total fatty acids in leg, while total DMA were liable for 3.6 and 0.9% of total FA plus DMA in breast and leg, respectively. The mallard duck meat total cholesterol content averaged 49.8 and 57.1 mg/100 g of fresh meat for breast and leg meat portions. Five tocochromanols were quantified in mallard duck meat, affording it with a total vitamin E content of 5.48 and 3.63 µg/g of fresh meat in breast and leg portions. The sex had no influence (P > 0.05) on mallard's duck meat lipid composition, but meat portion had a strong influence on mallard's duck meat lipid composition, influencing total lipid, total cholesterol, total vitamin E contents, FA partial sums, FA ratios (exception made for the n-6/n-3 ratio), and all nutritional lipid indices. The breast meat presented lower total lipid and total cholesterol contents, better FA ratios and nutritional quality indices and higher vitamin E content, being regarded as a healthier meat than leg. The study presented herein shows that mallard duck production in semiextensive conditions, similar to those used herein, could be used for the production of mallard duck beyond hunting. A production of duck's meat under natural or organic production practices, oriented to a market niche within the gourmet/organic markets.

Direct supplementation of diet is the most efficient way of enriching broiler meat with n-3 long-chain polyunsaturated fatty acids.

1. Concentrations of beneficial omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs) in poultry meat can be improved by increasing the concentration of n-3 PUFA in poultry diets. 2. A decrease in flavour quality is, however, usually associated with the dietary supplementation with n-3 PUFA, which is due to the susceptibility of PUFA to oxidation. 3. This experiment was conducted to study the effects of introducing two different n-3 fatty acid sources (extruded linseed and DHA Gold™, a proprietary algal product rich in docosahexaenoic acid), either separately or together, on broiler productive performance, and meat quality, oxidative stability, sensory traits and LC-PUFA profile. 4. Birds given the algal product displayed better productive performances than animals from other groups. 5. The data revealed an improvement in the fatty acid nutritional value of meat from birds receiving the algal product and an inefficient conversion of α-linolenic acid (LNA) into LC-PUFA. 6. Metabolisation of LNA in vivo is not sufficient to improve meat quality in n-3 LC-PUFA and direct supplementation of the diet with n-3 LC-PUFA is a better alternative to modulate an increase in beneficial fatty acids of broiler meat. 7. The overall acceptability of meat was negatively affected by the dietary supplementation with 7.4% of DHA, in contrast to the supplementation with 3.7% of DHA, which showed to be efficient in improving LC-PUFA meat content without affecting its sensory properties.

Nannochloropsis oceanica microalga feeding increases long-chain omega-3 polyunsaturated fatty acids in lamb meat.

To test the hypothesis that lambs fed freeze-dried Nannochloropsis oceanica (NO) biomass will have a higher deposition of EPA in tissues than those fed other Nannochloropsis EPA-sources, we fed 28 lambs with one of four diets: i) C, control, without EPA; ii) O, with 1.2% Nannochloropsis oil; iii) SD, with 12.3% spray-dried NO biomass; iv) FD, with 9.2% freeze-dried NO biomass. Dry matter intake, growth, tissues fatty acid composition, oxidative stability and sensory traits of the resultant meat were evaluated. The EPA was highest in tissues of lambs fed SD and FD compared with O but was similar between SD and FD. Total trans-18:1 did not differ among treatments, but the t10/t11-18:1 ratio decreased with all EPA containing diets. EPA diets were also supplemented with Vitamin E preventing the lipid oxidation in EPA-enriched meat and the meat sensory traits were not affected although occasionally some off-flavours were detected in FD meat.

Effect of trans-10 cis-12 conjugated linoleic acid on bovine oocyte competence and fatty acid composition.

The reproductive performance of dairy cows may be improved by feeding conjugated linoleic acid (CLA) supplements during early lactation. The mechanism of action of t10,c12 CLA is not clearly known. Our objective was to investigate the effect of t10,c12 CLA on oocyte maturation and lipid composition of cumulus oocyte complexes (COC). The developmental potential of oocytes incubated in in vitro maturation (IVM) medium supplemented with t10,c12 CLA to the blastocyst stage and embryo quality were also assessed. In experiment 1, abattoir-derived oocytes were matured in TCM199 + 10% serum supplemented with 100 µM t10,c12 CLA (t10,c12 CLA n = 672) or without it (control n = 672). Mature oocytes were either stained for chromatin configuration or inseminated and cultured for embryo development assessment. In experiment 2, COC and IVM culture media were subjected to fatty acid (FA) analysis prior and after maturation with t10,c12 CLA or without it (control). Total lipids and FA profiles in oocytes, cumulus cells and culture media were determined by gas chromatography. t10,c12 CLA supplementation to IVM medium improved (p = 0.05) embryo quality evaluated morphologically. This effect was associated with t10,c12 CLA presence (3.1 ± 0.7%, p = 0.04) and lower levels of arachidonic acid in FA profile of t10,c12 CLA mature oocytes (immature oocytes = 4.4 ± 1.9%, t10,c12 CLA mature oocytes = 1.0 ± 0.7%, p = 0.05). Differences in myristic and eicotrienoic acids, saturated and unsaturated FA concentrations between oocytes and cumulus cells were detected (p ≤ 0.05). In conclusion, the presence of t10,c12 CLA during maturation interfered on lipid metabolism improving bovine oocyte competence to develop into higher quality embryos.

The effect of Nannochloropsis oceanica feed inclusion on rabbit muscle proteome.

Nannochloropsis oceanica is a microalga, highly concentrated in protein and EPA (eicosapentaenoic acid). It has a recalcitrant cell wall that decreases nutrient digestibility. The objective of this study is to evaluate the effect of Nannochloropsis oceanica feed inclusion on the muscle proteome of fattening rabbits. Twenty rabbits were housed in individual cages for 5 weeks and were fed a control diet (n = 10) and one with 4.45% inclusion of microalga, replacing whole soybean meal (n = 10). After slaughter, samples of gastrocnemius muscle were taken for label-free proteomic analysis. A total of 1497 proteins were identified, 46 with differential abundance. Control rabbits had high abundance of proteins related to protein metabolism, suggesting higher muscle protein turnover. They also had higher abundance of structural proteins, suggesting a less tender meat by comparison with algae-fed rabbits. These had high abundance of proteins related to amino acid catabolism (Phe, Tyr) and synthesis (Gln). In addition, they had high abundance of proteins related to protein breakdown, overall suggesting that more tender meat may result from algae feeding. BIOLOGICAL SIGNIFICANCE: Microalgae are interesting feedstuffs particularly from a sustainability point of view. Their use in farm animal diets could simultaneously enhance the nutritional value and quality of meat. However, the biochemical pathways behind such improvement remain uncharacterized, namely in the rabbit species. By using a proteomics approach, this study will enlighten such biochemical pathways and relate them with productive performance parameters. In addition, results reflect some anti-nutritional properties of the recalcitrant cell wall over amino acid digestibility and consequently, its availability for protein synthesis.

Rumen biohydrogenation-derived fatty acids in milk fat from grazing dairy cows supplemented with rapeseed, sunflower, or linseed oils.

The effects of supplementation with rapeseed, sunflower, and linseed oils (0.5 kg/d; good sources of oleic, linoleic, and linolenic acids, respectively) on milk responses and milk fat fatty acid (FA) profile, with special emphasis on rumen-derived biohydrogenation intermediates (BI), were evaluated in a replicated 4 x 4 Latin square study using 16 grazing dairy cows. The dietary treatments were 1) control diet: 20-h access to grazing pasture supplemented with 5 kg/d of corn-based concentrate mixture (96% corn; CC); 2) RO diet: 20-h access to grazing supplemented with 4.5 kg/d of CC and 0.5 kg of rapeseed oil; 3) SO diet: 20-h access to grazing supplemented with 4.5 kg/d of CC and 0.5 kg of sunflower oil; and 4) LO diet: 20-h access to grazing supplemented with 4.5 kg/d of CC and 0.5 kg of linseed oil. Milk fatty acids were converted to methyl esters and analyzed by gas-liquid chromatography and silver-ion HPLC. Dietary treatments had no effect on milk production or on milk protein content and milk protein production. Supplementation with rapeseed and sunflower oils lowered milk fat content and milk fat production, but linseed oil had no effect. Inclusion of dietary vegetable oils promoted lower concentrations of short-chain (including 4:0) and medium-chain FA (including odd- and branched-chain FA) and 18:3n-3, and higher concentrations of C(18) FA (including stearic and oleic acids). The BI concentration was higher with the dietary inclusion of vegetable oils, although the magnitude of the concentration and its pattern differed between oils. The RO treatment resulted in moderate increases in BI, including trans 18:1 isomers and 18:2 trans-7,cis-9, but failed to increase 18:1 trans-11 and 18:2 cis-9,trans-11. Sunflower oil supplementation resulted in the highest concentrations of the 18:1 trans-10, 18:1 cis-12, and 18:2 trans-10,trans-12 isomers. Concentrations of 18:1 trans-11 and 18:2 cis-9,trans-11 were higher than with the control and RO treatments but were similar to the LO treatment. Concentration of BI in milk fat was maximal with LO, having the highest concentrations of some 18:1 isomers (i.e., trans-13/14, trans-15, cis-15, cis-16), most of the nonconjugated 18:2 isomers (i.e., trans-11,trans-15, trans-11,cis-15, cis-9,cis-15, and cis-12,cis-15), and conjugated 18:2 isomers (i.e., trans-11,cis-13, cis-12,trans-14, trans-11,trans-13, trans-12,trans-14, and trans-9,trans-11), and all conjugated 18:3 isomers. The LO treatment induced the highest amount and diversity of BI without decreasing milk fat concentration, as the RO and SO treatments had, suggesting that the BI associated with 18:3n-3 intake may not be the major contributors to inhibition of mammary milk fat synthesis.

The muscular, hepatic and adipose tissues proteomes in muskox (Ovibos moschatus): Differences between males and females.

The muskox (Ovibos moschatus) is a ruminant highly adapted to arctic conditions. The objective of this work is to study liver, muscle and adipose tissues proteomes in muskoxen highlighting sex differences. Ten animals (5 per sex) were sampled in Western Greenland during the winter hunting season. During carcass processing, muscle, liver and rump fat samples were obtained. Proteomic analyses were conducted using both gel-based and gel-free approaches. Gel-free data are available (ProteomeXchange; PXD014147). For gel-free analysis, 729, 853 and 792 proteins were identified for fat, liver and muscle, respectively. Several proteins were detected with differential abundance between male and female tissues: 77, 15 and 12 proteins using gel-free for adipose tissue, liver and muscle respectively while 3 differential proteins were identified in the gel-based analysis of the adipose tissue. Females have higher abundance of proteins involved in tissue structural stability in the muscle, while males have higher abundance of proteins related to muscle development. In the liver and adipose tissue, females have higher abundance of proteins related to oxidative-stress resistance. Proteins accumulated in the adipose tissue of males highlight higher adipogenic potential. Sex dimorphism is inherent to this species, with higher abundance of proteins in specific metabolic pathways. SIGNIFICANCE: The proteomes of the muskox muscle, hepatic and adipose tissues are characterized for the first time. In addition, the effect of sex on tissue protein abundance is studied. Our results reveal that sex dimorphism goes from morphology to the molecular level in this species, affecting protein, lipid and carbohydrate metabolism. This contributes for an in-depth look into sex dimorphism using proteomics which is lacking in most mammals, apart from model species. Moreover, this information has been related to nutritional status, which is particularly important when managing the muskox population and the transformation of its habitat in relation to external factors such as climate changes that can severely affect ecosystems.

Nutritional value of meat lipid fraction from red-legged partridge (Alectoris rufa) obtained from wild and farmed specimens1.

The red-legged partridge (Alectoris rufa) is a feathered game species of great socioeconomic importance in its native range and also in the UK. The aim of this study was to present a detailed comparison of meat's lipid fraction obtained from wild and farm-raised specimens and simultaneously compare the breast and leg meat portions. Meat from wild specimens had a significant (P < 0.05) lower proportion of saturated fatty acid (less 5.1%) and presented better P/S and n-6/n-3 ratios, and atherogenicity index than farm-raised counterparts. The wild specimens presented significant (P < 0.001) higher contents of total vitamin E (8.8 vs. 2.2 µg/g of fresh meat), is for that reason less prone to lipid peroxidation than farm-raised specimens. Meat portions differed significantly (P < 0.05) on total lipid and total cholesterol contents and in all partial sums of fatty acids. The breast was leaner (0.86 vs. 1.47 g/100 g of meat), with lower total cholesterol (37.5 vs. 54.7 mg/100 g of meat), lower saturated fatty acid, monounsaturated fatty acid, polyunsaturated fatty acid, and n-6 polyunsaturated fatty acid (less 0.27, 0.28, 0.10, and 0.11 g/100 g of fresh meat, correspondingly). Regarding the fatty acid ratios and lipid quality indexes, breast meat presents better n-6/n-3 ratio and atherogenicity and thrombogenicity indexes.

Effect of immunocastration and caponization on fatty acid composition of male chicken meat.

Recently, immunocastration with Improvac (ImmC). has been tested in broilers and a considerable reduction in serum testosterone concentration (reduced by 79% compared to roosters) was observed. The aim of this study was to evaluate the effect of immunocastration on meat fatty acid (FA) composition and its comparison with caponized and intact males (roosters). The study was conducted with 3 experimental groups: control group (roosters), the group of birds submitted to surgical caponization (SurgC), and the group of birds submitted to immunocastration with Improvac. The comparison of breast meat partial FA sums of castrated (SurgC and ImmC) with control birds (roosters) revealed that castrated birds showed significantly higher content of n-3 polyunsaturated fatty acids (n-3 PUFA) than control birds (1.76 vs. 1.46 g/100 g of total FA; superiority of 20.2%), which has contributed to the occurrence of significant differences on both the n-6/n-3 ratio and the atherogenicity index (AI). In contrast, on leg meat portion, castrated birds displayed higher contents of both total saturated and monounsaturated fatty acids (SFA and MUFA, with 2.2 and 4.1% more, respectively) and lower total n-6 PUFA content (8.3% less) than was observed in control birds, which contributed to significant differences in the AI index. On the other hand, the comparison of breast meat portion from SurgC with ImmC showed that immunocastration contributed to lower total SFA and higher total n-6 PUFA, which have contributed to significant differences on both Polyunsaturated/Saturated (P/S) and n-6/n-3 ratios. Whereas, on leg meat portion no significant differences were observed on partial sums and a single difference was observed on the thrombogenicity index. Immunocastration of broilers has contributed to minor changes in the FA profile, but has improved the overall lipid quality indexes in both breast and leg meat portions. Therefore, immunocastration could be applied as an alternative method to caponization without negative consequences in meat FA profile.

Effects of grass silage and soybean meal supplementation on milk production and milk fatty acid profiles of grazing dairy cows.

The effects of supplementation with grass silage and replacement of some corn in the concentrate with soybean meal (SBM) on milk production, and milk fatty acid (FA) profiles were evaluated in a replicated 4 x 4 Latin square study using 16 dairy cows grazing pasture composed of ryegrass, Kentucky bluegrass, and white clover. Each experimental period lasted for 3 wk. The 4 dietary treatments were PC, 20 h of access to grazing pasture, supplemented with 6 kg/d of corn-based concentrate mixture (96% corn; C); PCSB, 20 h of access to grazing pasture, supplemented with 6 kg/d of corn- and SBM-based concentrate mixture (78% corn and 18% SBM; CSB); SC, 7 h of access to grazing pasture during the day and 13 h of ad libitum access to grass silage at night, supplemented with 6 kg/d of C concentrate; and SCSB, 7 h of access to grazing pasture during the day and 13 h of ad libitum access to grass silage at night, supplemented with 6 kg/d of CSB concentrate. The concentrate mixtures were offered twice each day in the milking parlor and were consumed completely. Grass silage supplementation reduced dietary crude protein and concentration of total sugars, and dietary SBM inclusion increased dietary crude protein concentration and decreased dietary starch concentration. Milk yield and energy-corrected milk were increased by SBM supplementation of cows with access to grass silage. Milk protein concentration was lower in cows offered grass silage, regardless of whether SBM was fed. Dietary SBM inclusion tended to increase milk fat concentration. Plasma urea N was reduced by silage feeding and increased by SBM supplementation. Supplementation with grass silage overnight could represent a useful strategy for periods of lower pasture availability. Dietary inclusion of SBM in solely grazing cows had no effects on milk production and composition, exacerbated the inefficient capture of dietary N, and increased diet cost. Grass silage supplementation affected milk FA profiles, increasing both the FA derived from de novo synthesis and those derived from rumen microbial biomass, and decreasing the sum of C18 FA (mostly derived from diet or from mobilization of adipose tissue reserves). Milk fat concentrations of conjugated linoleic acid cis-9, trans-11, vaccenic acid (18:1 trans-11), and linolenic acid (18:3n-3) were unaffected by grass silage supplementation, suggesting that partial replacement of pasture by unwilted grass silage does not compromise the dietary quality of milk fat for humans.

Influence of pasture intake on the fatty acid composition, and cholesterol, tocopherols, and tocotrienols content in meat from free-range broilers.

Over the last centuries, Western diets acquired a dramatic imbalance in the ratio of polyunsaturated fatty acids (PUFA) to saturated fatty acids (SFA) with a concomitant reduction in the dietary proportion of n-3 PUFA. Pastures are a good source of n-3 fatty acids, although the effect of forage intake in the fatty acid profile of meat from free-range chicken remains to be evaluated. In addition, it is unknown if consumer interest in specialty poultry products derived from free-range or organic production systems is accompanied by a greater nutritional quality of these products. In this study, broilers of the RedBro Cou Nu x RedBro M genotype were fed on a cereal-based diet in portable floorless pens located either on subterranean clover (Trifolium subterraneum) or white clover (Trifolium repens) pastures. Control birds were maintained at the same site in identical pens but had no access to pasture. The capacity of ingested forage to modulate broiler meat fatty acid profiles and the meat content of total cholesterol, tocopherols, and tocotrienols was investigated in broiler chicks slaughtered at d 56. The results suggested that pasture intake (<5% DM) had a low impact on the fatty acid and vitamin E homologue profiles of meat from free-range broilers. However, breast meat from birds with free access to pasture presented lower levels of the n-6 and n-3 fatty acid precursors linoleic acid (18:2n-6) and alpha-linolenic acid (18:3n-3), respectively. In spring the levels of eicosapentaenoic acid (20:5n-3) in breast meat were significantly greater in birds consuming pastures, which suggests greater conversion of alpha-linolenic acid into eicosapentaenoic acid in these birds. Finally, when compared with meat from slower-growing genotypes obtained under the conventional European free-range production systems with slaughtering at d 81, meat from birds of the Ross genotype raised intensively and slaughtered at d 35 seemed to have greater nutritional quality.

Improving the lipid nutritive value of poultry meat through the incorporation of a dehydrated leguminous-based forage in the diet for broiler chicks.

Dehydrated forages are assumed to be good sources of alpha-linolenic acid (ALA) and lipid-soluble antioxidant compounds (vitamin E homologs and beta-carotene). The effects of including a dehydrated leguminous-based forage in a typical diet for broiler chicken, on performance, meat quality, and fatty acid composition were evaluated. One hundred sixty 1-d-old male commercial broiler chicks (Ross 308) were housed in 20 battery brooders. During the 28-d growth period, the animals were fed ad libitum with a typical maize-soybean high-energy feed having access or not to a dehydrated leguminous-based forage provided in a separate feeder. The results revealed that dehydrated forage intake (which was 11.1% of the total intake) had no impact in broiler performance (P > 0.05). The capacity of ingested forage to modulate broiler meat fatty acid profile and the meat content in total cholesterol, tocopherols, tocotrienols, and beta-carotene was investigated in broiler chicks slaughtered at d 28. Dehydrated forage consumption had no effect on the lipid-soluble antioxidant compounds and cholesterol contents of broiler meat but had a significant effect on meat fatty acid profile. Although forage intake did not affect the linoleic acid and ALA contents in poultry meat, the levels of n-3 long-chain polyunsaturated fatty acids [eicosapentaenoic (P = 0.004), docosapentaenoic (P = 0.010), and docosahexaenoic (P = 0.007)] in breast meat were significantly higher in animals consuming leguminous biomass, which suggest a higher conversion of ALA into its derivatives in these birds. Overall, the data confirms that incorporation of a dehydrated leguminous-based forage in the diet for broiler chicks results in more favorable polyunsaturated fatty acids/saturated fatty acids and n-6/n-3 nutritional ratios for animals slaughtered at earlier stages of grow.

Restricting the intake of a cereal-based feed in free-range-pastured poultry: effects on performance and meat quality.

Pastures are assumed to be good sources of alpha-linolenic acid (ALA) and other bioactive compounds. In this study, we evaluated the effects of restricting the intake of a cereal-based feed on the consumption of a legume-based pasture, and consequently on poultry performance and meat quality. Broilers of the RedBro Cou Nu x RedBro M genotype were fed a cereal-based feed at different intake restriction levels (100, 75, or 50% of ad libitum intake) in portable floorless pens located on a subterranean clover (Trifolium subterraneum) pasture. Control birds were maintained at the same site in identical pens but had no access to pasture. The results revealed that, although the growth rate achieved was below the levels expected for the genotype, restriction of cereal-based feed intake had a significant impact on broiler weight gain and feed conversion while leading to an increase in relative leguminous pasture intake (from 1.6 to 4.9% of the total intake, on a DM basis). In addition, bird performance was positively influenced by pasture consumption. The capacity of ingested pasture to modulate carcass characteristics, broiler meat fatty acid profiles, and the meat content of total cholesterol, tocopherols, and to-cotrienols was investigated in broiler chickens slaughtered on d 64. Pasture intake decreased carcass yield (P < 0.05) and meat pH (P < 0.001) and improved breast skin pigmentation (P < 0.001). Consumption of the leguminous pasture had a marginal effect in the vitamin E profiles and cholesterol contents of broiler meat (P < 0.05), although it significantly affected the meat fatty acid profile. Although pasture intake did not influence the linoleic acid content of poultry meat, the levels of n-3 polyunsaturated fatty acids in breast meat [ALA (P < 0.001), eicosapentaenoic acid (P < 0.001), docosapentaenoic acid (P < 0.001), and docosahexaenoic acid (P < 0.001)] were significantly greater in birds consuming the leguminous biomass. Overall, the data suggest an important deposition of ALA and some conversion of ALA to its derivatives in pastured broilers subjected to a restriction of cereal-based feed.

Evaluation of the effects of different diets on microbiome diversity and fatty acid composition of rumen liquor in dairy goat.

Fat supplementation plays an important role in defining milk fatty acids (FA) composition of ruminant products. The use of sources rich in linoleic and α-linolenic acid favors the accumulation of conjugated linoleic acids isomers, increasing the healthy properties of milk. Ruminal microbiota plays a pivotal role in defining milk FA composition, and its profile is affected by diet composition. The aim of this study was to investigate the responses of rumen FA production and microbial structure to hemp or linseed supplementation in diets of dairy goats. Ruminal microbiota composition was determined by 16S amplicon sequencing, whereas FA composition was obtained by gas-chromatography technique. In all, 18 pluriparous Alpine goats fed the same pre-treatment diet for 40±7 days were, then, arranged to three dietary treatments consisting of control, linseed and hemp seeds supplemented diets. Independently from sampling time and diets, bacterial community of ruminal fluid was dominated by Bacteroidetes (about 61.2%) and Firmicutes (24.2%) with a high abundance of Prevotellaceae (41.0%) and Veillonellaceae (9.4%) and a low presence of Ruminococcaceae (5.0%) and Lachnospiraceae (4.3%). Linseed supplementation affected ruminal bacteria population, with a significant reduction of biodiversity; in particular, relative abundance of Prevotella was reduced (-12.0%), whereas that of Succinivibrio and Fibrobacter was increased (+50.0% and +75.0%, respectively). No statistically significant differences were found among the average relative abundance of archaeal genera between each dietary group. Moreover, the addition of linseed and hemp seed induced significant changes in FA concentration in the rumen, as a consequence of shift from C18 : 2n-6 to C18 : 3n-3 biohydrogenation pathway. Furthermore, dimethylacetal composition was affected by fat supplementation, as consequence of ruminal bacteria population modification. Finally, the association study between the rumen FA profile and the bacterial microbiome revealed that Fibrobacteriaceae is the bacterial family showing the highest and significant correlation with FA involved in the biohydrogenation pathway of C18 : 3n-3.

Lipid profile and quality indices of ostrich meat and giblets.

In this study, the lipid profile of 5 different edible tissues (leg, thigh, heart, gizzard, and liver) of ostrich was analyzed. Ostrich edible tissues presented a low fat content (<5 g/100 g wet basis). Gizzard and heart revealed the highest amounts of total cholesterol (1.77 and 1.47 mg/g wet basis, respectively), differing significantly from all other tissues (which averaged 0.95 mg/g wet basis). The main tocochromanol in all tissues was α-tocopherol (10.3 µg/g wet basis in heart and an average of 3.4 µg/g wet basis for all the remaining tissues). All the samples presented a fatty acid profile, dominated by polyunsaturated fatty acids (PUFA) (>38%), namely, linoleic and arachidonic acids. The leg presented simultaneously the highest PUFA/saturated fatty acids (SFA), the lowest n-6/n-3 ratios, and the most favorable lipid quality indices among all tissues in comparison.

Effects of dietary inclusion of citrus pulp and rockrose soft stems and leaves on lamb meat quality and fatty acid composition.

Meat from lambs finished with high-starch diets often contains low concentration of vaccenic (t11-18:1) and rumenic (c9,t11-18:2) acids and high concentration of t10-18:1. We hypothesized that replacing cereals by dehydrated citrus pulp (DCP) and the inclusion of tanniferous feed sources in oil supplemented diets might reduce the accumulation of t10-18:1 and increase the t11-18:1 and c9,t11-18:2 in lamb meat, without affecting the productive performance. In total, 32 lambs were assigned to four diets which combine two factors: basal diet (BD) (cereals v. DCP) and Cistus ladanifer (CL) (0 v. 150 g/kg dry matter). Feed intake, average daily weight gain and carcass traits were not affected by treatments, except for dressing percentage that was reduced with DCP (P=0.046). Both DCP and C. ladanifer reduced tenderness and juiciness of meat, and C. ladanifer also reduced (P0.05) by diets. However, DCP increased the proportions of odd-chain FA (P=0.005) and several minor biohydrogenation (BH) intermediates in meat lipids. C. ladanifer had few effects on meat FA profile. The proportions of t11-18:1 and c9,t11-18:2 were high in all diets (5.4% and 1.5% of total FA, respectively) and were not influenced by the treatments. Basal diet and CL showed some significant interactions concerning FA composition of intramuscular fat. In diets without C. ladanifer, replacement of cereals by DCP increased the 18:0 (P<0.05) and decreased t10,c12-18:2 (P<0.05), t10-18:1 (P<0.10) and t10-/t11-18:1 ratio (P<0.10) with a large reduction of the individual variation for t10-18:1 and of t10-/t11-18:1 ratio. Combined with cereals, C. ladanifer increased 18:0 and reduced the BH intermediates in meat. Replacement of cereals by DCP seems to promote a more predictable FA profile in lamb meat, reducing the risk of t10-shifted BH pathways in the rumen.

Effects of dietary protein and starch on intake, milk production, and milk fatty acid profiles of dairy cows fed corn silage-based diets.

Feed intake, milk production, and milk fatty acid profiles of dairy cows fed corn silage-based diets with different protein and starch concentrations were measured in a 3-period experiment in a changeover design using 12 Holstein cows. Each experimental period lasted for 3 wk. The diet fed as a total mixed ration consisted of 45% corn silage, 5% coarsely chopped wheat straw, and 50% concentrate, on a dry matter (DM) basis. The 4 treatments, formulated to be isoenergetic and to differ in concentrations of dietary crude protein (CP) and starch (DM basis), were as follows: low CP and low starch (LPLS; 14% CP and 15% starch), low CP and high starch (LPHS; 14% CP and 25% starch), high CP and low starch (HPLS; 16% CP and 15% starch), and high CP and high starch (HPHS; 16% CP and 25% starch). The LPLS treatment led to lower DM intake, milk yield, milk protein concentration, and milk lactose yield, probably due to a shortage of both rumen-degradable protein supply to rumen microbes and glucogenic nutrients to the animal. There were no differences between protein-rich diets and LPHS, suggesting that this diet satisfied the rumen-degradable protein requirements of rumen microbes and did not limit feed intake, and the increased supply of glucogenic nutrients spared AA so that the nutrient requirements of mid lactation dairy cows were met. Further increases in CP concentration increased plasma urea concentration and resulted in decreased efficiency of conversion of dietary N into milk N. Milk fatty acid profiles were affected by starch and protein supply, with starch having the largest effect. Additionally, increasing dietary starch concentration decreased the apparent transfer of dietary polyunsaturated fatty acids to milk, suggesting an increased channeling of fatty acids to adipose tissue. The results further suggest that C(15:0) and C(17:0) are synthesized de novo in animal tissues.