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.

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.

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.

Production of low-cholesterol butter with Lacticaseibacillus paracasei immobilized in calcium-alginate beads.

This study focused on the application of three strains of Lacticaseibacillus paracasei to assimilate cholesterol in cream and butter. The strains were enclosed in calcium-alginate beads and incubated in cream at 30 °C for 15 h. Immobilization of lactobacilli cultures in calcium-alginate beads resulted in a 23% reduction in cholesterol (p < 0.05) in cream, whereas a negligible reduction was observed in cream fermented with free cells. Butter with a 44% reduction in cholesterol was produced from fermented cream by L. paracasei L2A21K5 entrapped in alginate beads. No significant (p > 0.05) changes in the fatty acid profile were observed in the low-cholesterol butter, except for a slight but significant increase in n-3 fatty acids (p < 0.05). In addition, the indices of atherogenicity and thrombogenicity were significantly reduced in the low-cholesterol butter (p < 0.05). Panelists rated the low-cholesterol butter as good in appearance, consistency, and flavor.

The effects of improving low dietary protein utilization on the proteome of lamb tissues.

Cistus ladanifer L. is a common shrub endemic to the Mediterranean region with high levels of condensed tannins (CT). CT form complexes with dietary protein resisting microbial degradation in the rumen, which enhances dietary protein utilization in ruminant diets. The objective of this study was to evaluate the utilization of CT in the diet of lambs on the proteomes of muscle, hepatic and adipose tissues. Twenty-four Merino Branco ram lambs were randomly allocated to three treatments (n = 8): C - control (160 g crude protein (CP)) per kg DM, RP - reduced protein (120 g CP/kg DM); and RPCT - reduced protein (120 g CP/kg DM) treated with CT extract. At the end of the trial, lambs were slaughtered and the longissimus lumborum muscle, hepatic and peri-renal adipose tissues sampled. A two-way approach was used for proteomic analysis: 2D-DIGE and nanoLC-MS. In the muscle, C lambs had lower abundance proteins that partake in the glycolysis pathway than the lambs of other treatments. Control lambs had lower abundance of Fe-carrying proteins in the hepatic tissue than RP and RPCT lambs. The latter lambs had highest abundance of hepatic flavin reductase. In the adipose tissue, C lambs had lowest abundance of fatty-acid synthase. SIGNIFICANCE: soybean meal is an expensive feedstuff in which intensive animal production systems heavily rely on. It is a source of protein extensively degraded in the rumen, leading to efficiency losses on dietary protein utilization during digestion. Protection of dietary protein from extensive ruminal degradation throughout the use of plants or extracts rich in CT allow an increase in the digestive utilization of feed proteins. In addition to enhance the protein digestive utilization, dietary CT may induce other beneficial effects in ruminants such as the improvement of the antioxidant status.

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.

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.

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.

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.

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.

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.

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.

Immunocastration as an alternative to caponization: evaluation of its effect on body and bone development and on meat color and composition.

Caponization is associated with some morbidity and mortality, which contributes to important economic losses. This practice is executed without any pain relief (neither anesthesia nor analgesia) and can be painful and without consideration of animal welfare. On the other hand, immunocastration accomplished by Improvac and Bovipriva in pigs and cattle represents a noninvasive procedure, and for that reason is regarded as an alternative with improved animal welfare. This study includes 4 experimental groups consisting of capons, slips, roosters, and birds submitted to the Improvac treatment. The administration of Improvac was associated with a considerable reduction in serum testosterone concentration (reduced by 79% compared to average serum testosterone of roosters). Regarding significant differences among experimental groups, birds from the Improvac group were intermediate between capons and slips with respect to abdominal fat pad weight and yield, breast meat water and protein contents, and femur length. Conversely, color parameters such as lightness, redness, and hue angle for Improvac birds were intermediate between roosters and capons. Thus, immunocastration with Improvac could represent an alternative solution to caponization, with considerable improvements in animal welfare.

The reduction of starch in finishing diets supplemented with oil does not prevent the accumulation of trans-10 18:1 in lamb meat.

The experiment was conducted to test the hypothesis that the replacement of cereal with low-starch feed ingredients in lambs' finishing diets supplemented with oils could prevent the accumulation of -10-18:1 in meat. Forty lambs were fed 1 of 4 diets supplemented with soybean oil (5.9%) and fish oil (1%) for 6 wk before slaughter. The control (CON) diet contained 43% barley, and in the other diets, barley was completely replaced by dehydrated citrus pulp (DCP), dehydrated sugar beet pulp (DBP), or soybean hulls (SH). Growth performance, feed intake, and carcass and meat quality traits were analyzed. At slaughter, LM samples were collected for gene expression evaluation, and 3 d after slaughter, LM and subcutaneous (s.c.) fat samples were collected for fatty acid analysis. None of the diets affected meat quality, but the DCP diet reduced ADG ( < 0.05) and the DCP and SH diets decreased the feed-to-gain ratio ( < 0.01). The DCP diet increased ( < 0.05) the risk of parakeratosis and the severity of the lesions. Moreover, the DBP treatment led to increased a* (redness) and b* (yellowness) in s.c. fat compared with the CON treatment ( < 0.05). The lipid content of LM did not differ ( > 0.05) with treatment and averaged 34.4 g/kg of meat. Diets had no effect ( > 0.05) on SFA, PUFA, and -MUFA sums and on the -6:-3 ratio in both LM and s.c. fat. A lower expression of fatty acid synthase (FASN) was found with the DCP treatment than with the other treatments ( < 0.001). All treatments showed a high accumulation of -10-18:1, averaging 91 mg/g fatty acid in LM and 147 mg/g fatty acid in s.c. fat. The concentration of -11-18:1 in the tissues was considerably lower than that of -10-18:1, and thus the -10-18:1:-11-18:1 ratio was above 3 with all treatments. Despite this, the SH diet clearly promoted a larger deposition of -11-18:1 and -9,-11-18:2 in tissues compared with the other treatments. () gene expression and SCD activity index in LM were reduced with the SH diet compared with the CON and DCP diets. Overall, these results clearly showed, for the first time, that low-starch/high-NDF diets are not able to prevent the establishment of -10 shifted rumen biohydrogenation pathways, evaluated by the deposition of biohydrogenation intermediates in lamb meat and fat.

Beef palatability and its relationship with protein degradation and muscle fibre type profile in longissimus thoracis in Alentejana breed from divergent growth pathways.

The traditional beef production in the South of Portugal is based on a discontinuous growth (DG) system that requires lower external inputs and could enhance meat quality and financial returns to cattle producers. This system allows farmers to take advantage of the bull's compensatory growth when the pasture is abundant and finishes the cattle on concentrates for 2 to 3 months before slaughter. The fast gain rate before slaughter could be a valuable strategy to improve tenderness and to reduce its inconsistency in beef production. Therefore, the aim of this study was to evaluate the effects of production system (continuous growth (CG) v. DG) on longissimus thoracis muscle properties from Alentejana bulls. In total, 40 Alentejana male calves were allocated to two distinct feeding regimes: in the CG system, animals were fed concentrate plus hay and slaughtered at 18 months of age, whereas in the DG system, animals were fed on hay until 15 months of age and then fed the same diet provided to the CG group until 24 months of age. The DG system had a positive impact on meat tenderness (P<0.001) and global acceptability (P<0.001). DG bulls had greater fibre cross-sectional area (CSA) of glycolytic fibres (P<0.05) and relative area of the muscle (RA) occupied by type IIX fibres (P<0.01) and greater levels of α-actinin (P<0.05) and myosin light chain 2 (P<0.01) proteins, and pH24h (P<0.01) than CG bulls. The latter had greater CSA of type I (P<0.05) and type IIA (P<0.01) and greater RA of type IIA (P<0.05) and oxidative (P<0.05) than CG bulls. The compensatory growth production system had a positive impact on meat tenderness and global acceptability, overcoming the negative effects of slaughter of the bulls at a later age. The DG beef system could be a worthwhile strategy of beef production in Mediterranean areas due to the low-quality pasture in summer.

Quality of eggs from different laying hen production systems, from indigenous breeds and specialty eggs.

Consumers are concerned about the quality of commercially available eggs. Eggs used in this study were marketed in Portugal and originated from laying hens raised in cages, barns, free-range, organic eggs, and eggs enriched with n-3 polyunsaturated fatty acids (PUFA), and from native Portuguese breeds. The eggs were analyzed for chemical and physical properties. Results indicated that yolk color was lighter in organic eggs and darker in n-3 PUFA enriched eggs. Eggs from caged hens had lower Haugh units in contrast with organic eggs. Caged hens produced eggs with a higher protein content while organic eggs had the lowest level of protein in the albumen. As might be expected, eggs enriched in n-3 PUFA had the highest n-3 PUFA content. Choosing an egg by its production system or labeling specificities may not be a guarantee of superior product quality. The layer genotype, age, diet, and the quality of the range also may affect egg properties. Due to a different layer diet, enriched eggs seem to be of superior quality.

Effect of feeding lambs with a tanniferous shrub (rockrose) and a vegetable oil blend on fatty acid composition of meat lipids.

The effects of feeding Cistus ladanifer (Cistus) and a blend of soybean and linseed oil (1 : 2 vol/vol) on fatty acid (FA) composition of lamb meat lipids and messenger RNA (mRNA) expression of desaturase enzymes was assessed. In total, 54 male lambs were randomly assigned to 18 pens and to nine diets, resulting from the combination of three inclusion levels of Cistus (50 v. 100 v. 200 g/kg of dry matter (DM)) and three inclusion levels of oil (0 v. 40 v. 80 g/kg of DM). The forage-to-concentrate ratio of the diets was 1 : 1. Longissimus muscle lipids were extracted, fractionated into neutral (NL) and polar lipid (PL) and FA methyl esters obtained and analyzed by GLC. The expression of genes encoding Δ5, Δ6 and Δ9 desaturases (fatty acid desaturase 1 (FADS1), fatty acid desaturase 2 (FADS2) and stearoyl CoA desaturase (SCD)) was determined. Intramuscular fat, NL and PL contents were not affected by oil or Cistus. Oil supplementation reduced (P<0.05) 16:0, c9-16:1, 17:0, c9-17:1 and c9-18:1 FA and increased (P<0.05) 18:2n-6, 18:3n-3 and the majority of biohydrogenation intermediates in NL. Cistus alone had few effects on FA of NL but interacted with oil (P<0.05) by increasing t10-18:1,t10,t12-18:2,t10,c12-18:2 and t7,c9-18:2. The t10-/t11-18:1 ratio increased with both Cistus and oil levels. The c9, t11-18:2 did not increase (P<0.05) with both oil and Cistus dietary inclusion. Oil reduced c9-16:1, 17:0, c9-17:1,c9-18:1, 20:4n-6, 22:4n-6 and 20:3n-9 proportions in PL, and increased 18:2n-6, 18:3n-3, 20:3n-3 and of most of the biohydrogenation intermediates. The Cistus had only minor effects on FA composition of PL. Cistus resulted in a reduction (P<0.05) of 20:5n-3 and 22:6n-3 in the meat PL. The expression level of SCD mRNA increased (P=0.015) with Cistus level, although a linear relationship with condensed tannins intake (P=0.11) could not be established. FADS1 mRNA expressed levels increased linearly (P=0.019) with condensed tannins intake. In summary, the inclusion of Cistus and oil in 1 : 1 forage-to-concentrate ratio diets resulted in a large increase in t10-18:1 and no increase in c9,t11-18:2 or n-3 long chain poor in polyunsaturated fatty acids in lamb meat.

Effect of betaine and arginine in lysine-deficient diets on growth, carcass traits, and pork quality.

Forty entire male pigs from a commercial crossbreed (Duroc × Large White × Landrace) were used to investigate the individual or combined effects of betaine and Arg supplementation in Lys-deficient diets on growth performance, carcass traits, and pork quality. Pigs with 59.9 ± 1.65 kg BW were randomly assigned to 1 of 5 dietary treatments ( = 8). The 5 dietary treatments were normal Lys and CP diet (0.51% Lys and 16% CP; control), reduced Lys and CP diet (0.35% Lys and 13% CP), reduced Lys and CP diet with betaine supplementation (0.33%), reduced Lys and CP diet with Arg supplementation (1.5%), and reduced Lys and CP diet with betaine and Arg supplementation (0.33% betaine and 1.5% Arg). Pigs were slaughtered at 92.7 ± 2.54 kg BW. The Lys-deficient diets (-35% Lys) increased intramuscular fat (IMF) content by 25% ( = 0.041) and meat juiciness by 12% ( = 0.041) but had a negative effect on growth performance ( < 0.05) of pigs. In addition, Lys-deficient diets increased L* ( = 0.005) and b* ( = 0.010) muscle color parameters and perirenal fat deposition ( < 0.001) and decreased both HCW ( = 0.015) and loin weight ( = 0.023). Betaine and Arg supplementation of Lys-deficient diets had no effect on IMF content but increased ( < 0.05) overall pork acceptability. Arginine supplementation also increased ( = 0.003) meat tenderness. Differences in fatty acid composition of pork were not detected among dietary treatment groups. However, oleic acid was positively correlated ( < 0.05) with IMF content, juiciness, flavor, and overall acceptability of meat. Data confirm that dietary CP reduction enhances pork eating quality but negatively affects pigs' growth performance. Moreover, it is suggested that betaine and Arg supplementation of Lys-deficient diets does not further increase IMF content but improves some pork sensory traits, including overall acceptability.