Effect of vitamin E supplementation and diet on fatty acid composition and on meat colour and lipid oxidation of lamb leg steaks displayed in modified atmosphere packs

Groups of 8 lambs were allocated to one of five concentrate diets supplemented with all-rac-α-tocopheryl acetate containing 30 (C30), 60 (C60), 120 (C120), 250 (C250) and 500 (C500) mg/kg dry matter. Two other groups were fed grass silage and 400 g/day concentrate with 60 (S60) or 500 (S500) mg α-tocopheryl acetate/kg dry matter. Within diet, vitamin E level did not affect growth performance or carcass characteristics. Basal diet did not affect final live weight, conformation and fatness scores. M. semimembranosus from S lambs contained more α-tocopherol than that of C lambs on the same intake and by day 6 in MAP (75%O2/25%CO2) chroma and a* were below acceptable levels in C30 lambs. TBARS were higher in C30 and C60 muscle than in other treatments (P < 0.001) after 3 and 6 days display. Muscle fatty acid composition varied with basal diet but lipid oxidation depended more on vitamin E concentration with an initial concentration of 1.9 μg/g muscle preventing significant lipid oxidation.     

Effects of oral vitamin D(3) supplementation and supplement withdrawal on the accumulation of magnesium, calcium, and vitamin D in the serum, liver, and muscle tissue and subsequent carcass and meat quality of Bos indicus influenced cattle

Bos indicus crossbred cattle (n=79) were fed vitamin D(3) (0 or 3 million IU/hd/d) for 5d. Afterwards, half of each group was slaughtered immediately, while half was fed, without supplementation, for 7d before processing. Serum calcium concentration was increased (P<0.05) in cattle after supplement removal, but not immediately following supplementation. This also was observed in the M. longissimus lumborum and M. triceps brachii, but not in the M. semitendinosus. Liver biopsy vitamin D(3) concentrations were higher (P<0.05) in supplemented cattle immediately following supplementation, but were not different from controls after supplement removal. Vitamin D(3) did not affect tenderness at supplement removal day 0, but increased the tenderness of the M. longissimus lumborum and M. semitendinosus at supplement removal day 7. Vitamin D(3) supplementation improves muscle tenderness and may be more effective when supplementation is ceased 7d before slaughter, with minimum food safety concerns.     

Peripartum serum vitamin E, retinol, and beta-carotene in dairy cattle and their associations with disease

Peripartum decreases in serum concentrations of vitamins A and E may contribute to impaired immune function in dairy cows. The objectives of this study were to describe peripartum serum concentrations of alpha-tocopherol, beta-carotene, and retinol and their associations with disease risk. On 20 farms over 1 yr, blood samples were collected weekly from 1057 cows from 1 wk before expected calving until 1 wk postpartum. Serum concentrations of alpha-tocopherol, beta-carotene, and retinol, as well as several biochemical variables were measured. Their associations with the risk of retained placenta or clinical mastitis were modeled separately with logistic regression, and the factors associated with the concentration of each vitamin were modelled with mixed linear regression. Differences in vitamin concentrations between 2 batches of sera analyzed 6 mo apart required stratification of statistical analyses. Accounting for the effects of parity, season, and twins, an increase in alpha-tocopherol of 1 microg/mL in the last week prepartum reduced the risk of retained placenta by 20%, whereas serum nonesterified fatty acid concentration > or = 0.5 mEq/L tended to increase risk of retained placenta by 80%. In the last week prepartum, a 100 ng/mL increase in serum retinol was associated with a 60% decrease in the risk of early lactation clinical mastitis. There were significant positive associations of peripartum serum concentrations among each of alpha-tocopherol, beta-carotene, and retinol.     

Fatty acid and vitamin E composition of intramuscular fat in cattle reared in different production systems

The aim of this study was to evaluate the fatty acid composition of intramuscular fat and the vitamin E content of beef from different production systems. Four cattle production systems were used: cattle reared under intensive conditions and fed concentrate (INT1) from Spain, cattle raised at pasture and supplemented with concentrate (SUP1) from the United Kingdom, cattle raised at pasture and on corn silage (SUP2) from Germany and cattle reared under extensive conditions slaughtered at two and three years old (EXT2 and EXT3) from Uruguay. The highest proportion and content (mg per 100 g of muscle) of linoleic acid (C18:2n-6) and arachidonic acid (C20:4n-6) and the lowest saturated fatty acids (SFA) was found in INT1 beef. In contrast, beef reared under extensive conditions showed the highest proportion and content of linolenic acid (C18:3n-3), docosapentaenoic acid (DPA, C22:5n-3) and eicosapentaenoic acid (EPA, C20:5n-3), and SUP1 and SUP2 beef showed the highest level of palmitic acid (C16:0) and SFA. Beef from intensive system (INT1) had the lowest P/S (PUFA/SFA) ratio, whereas beef from extensive system (EXT2 and EXT3) had the lowest n-6/n-3 ratio. The results of the PCA (principal components analysis) of fatty acid composition showed that beef from intensive system (INT1) was clearly differentiated from the other meats and was located with the C18:2n-6 and C20:4n-6 and the n-6/n-3 ratio. EXT2 and EXT3 beef were located with C18:3n-3 and long chain fatty acids. Beef from extensive systems had the highest concentration of vitamin E (3.91 mg α-tocopherol/kg muscle).     

Effects of dietary vitamin A restriction during finishing on color display life, lipid oxidation, and sensory traits of longissimus and triceps brachii steaks from early and traditionally weaned steers

Our objective was to determine the effects of vitamin A restriction during finishing on color display life, lipid oxidation, and sensory traits of longissimus lumborum (LL) and triceps brachii (TB) steaks from early and traditionally weaned steers. Forty-eight steers weaned at either 137 ± 26 days (EW) or 199 ± 26 days (TW) were supplemented with either 15,400 IU/kg dry matter of vitamin A (HA) or restricted to no supplemental vitamin A (LA) during finishing for 210 and 150 days, respectively. Both LL and TB steaks from the HA steers had the darkest (P < 0.05) color scores after 3 days of retail display in PVC packaging at 2 °C, and the highest (P < 0.05) thiobarbaturic acid reactive substances (TBARS) values. Instrumental a∗, b∗, and saturation index values were lowest (P < 0.05) in LL steaks from the HA steers. Instrumental L∗ values were lower (P < 0.05) on days 4–6 in TB steaks from TW steers fed LA than those from EW steers fed HA. No differences were found in Warner–Bratzler shear force values or sensory traits in either muscle. No supplemental vitamin A versus high levels of vitamin A inclusion in finishing diets has potential to increase color display life and reduce lipid oxidation, with no effects on meat palatability.     

Effects of chestnut tannins on carcass characteristics, meat quality, lipid oxidation and fatty acid composition of rabbits

Seventy two male Bianca Italiana rabbits were used to study the effects of the inclusion (0%, 0.5%, and 1.0%) of a natural extract of chestnut wood (Silvafeed ENC) in the diet on productive traits, carcass characteristics, meat quality, lipid oxidation and fatty acid composition of rabbit meat. Results showed ENC had no significant effect on live weight, productive traits, hot carcass weight, dressing percentage, skin weight, pH, cooking losses, shear force and colour. The iron content was higher in Longissimus thoracis et lumborum (LTL) muscle of rabbit fed the ENC 1.0% diet than the control group. TBARS average values in the group ENC 0.5% were significantly lower (P < 0.05) than in the control and ENC 1.0% groups. Myristic acid (C14:0; P < 0.01), palmitoleic acid (C16:1 cis-9; P < 0.05) and pentadecanoic acid (C15:0; P < 0.01) contents were lower in LTL muscle of rabbits fed the ENC 1.0% diet, whereas the palmitic acid (C16:0) content was higher (P < 0.05) in the rabbits of this group. Moreover, the rabbits fed with the ENC 0.5% diet had lower (P < 0.01) levels of trans-vaccenic acid (C18:1 trans-11) compared to rabbits fed with the control diet. No significant differences were observed in saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA) fatty acids, as well as in PUFA/SFA and n − 6/n − 3 ratios among the groups.     

Effect of maternal age on milk production traits, fertility, and longevity in cattle

Longevity is the economically most important functional trait in cattle populations. However, with an increased productive lifespan, the number of offspring born by older dams increases. A higher maternal age might have negative effects on the performance of offspring. The objective of this study was to investigate the effect of maternal age on production (energy-corrected milk yield [ECM]) and functional traits (fertility; somatic cell score, and functional longevity) in Austrian dual-purpose Simmental cows. Age of dam had a significant effect on ECM yield and longevity. The ECM yield of daughters decreased with age of dam. Although the risk of culling slightly increased with age of dam, it was lowest for daughters of oldest dams. Results for fertility were non-significant, and results for somatic cell scores were inconsistent across parities.     

Effect of diet on animal performance, lipid composition of subcutaneous adipose and liver tissue of beef cattle

Two trials were carried out with Brahman beef cattle to study animal performance and carcass characteristics as well as fatty acid composition of subcutaneous adipose and hepatic tissue, as influence by length of grain feeding period or a pasturing regimen. In trial 1, steers were allotted to three feedlot finishing periods (76, 104 and 146 days) after being backgrounded on pasture. Steers fed 76 days had greater average daily gains (P < 0·05) than steers fed 146 and 104 days, respectively. Carcasses of steers slaughtered after 146 days on feed had higher (P < 0·05) marbling scores, quality grades, fat over ribeye, quality yield and per cent kidney, pelvic and heart (KPH) fat than steers fed for 104 and 76 days. The proprortions of certain fatty acid of subcutaneous fat and liver tissue were influenced by the length of grain feeding. There was a marked increased in the proportion of oleic acid in both tissues as the steers remained longer in the feedlot and a higher percentage of total saturated fatty acids at 76 days than at the other two times. Quantitative separation of hepatic lipid classes by the Iatroscan revealed that phosphatidylcholine and phosphatidylethanolamine were the main components of the phospholipids. Presents as minor components were cardiolipin and sphingomyelin. No differences (P > 0.·05) in these individual subclasses of liver lipids or in triglycerides were observed between the feedlot groups. Liver polyunsaturated fatty acids (PUFA) were higher (P < 0·001) at 104 than 76 days. In trial 2, steers fed a concentrate diet gained faster (P < 0·05) than the pasture group after 138 days. Marbling scores, yield grade, quality grade, fat over ribeye and per cent KPH were higher (P < 0·01) for the concentrate group while fat color scores were higher (P < 0·01) for the pasture group. Liver fatty acid analysis of summed ω6 PUFAs of triglyceride, phosphatidylcholine, phosphatidylethanolamine were higher for the feedlot than the pasture group. Linoleic acid was higher (P < 0·05) in the TG and PC liver subclass of the feedlot animals while higher (P < 0·05) linolenic acid occurred in the pasture group.     

Effects of dietary vitamin E supplementation and packaging on the colour stability of sliced pasteurized beef ham

The effect of supplementation of vitamin E (2025 IU animal⁻¹ day⁻¹) in the diet of beef bulls on the colour stability of pasteurized beef ham was studied. Control and enriched diets were provided for the last 136 days before slaughter. Pasteurized hams were manufactured from Mm. semitendinosus from eight animals per dietary group. Half of the samples of sliced ham from control (CON) and supplemented (SUP) bulls were packaged under vacuum (VAC) and half in low-oxygen modified atmosphere packs (FOG, gas mixture: CO₂/N₂=50/50). The packages were kept under constant illumination for 28 days at 8°C. During storage, the number of colony-forming units (CFU) reached a maximum of 5x10⁷ g⁻¹. The microflora was dominated by lactic acid bacteria. The supplementation with vitamin E showed no effect on microbial growth. Lipid oxidation was stable during storage. A significant difference between both dietary groups was detected for the decrease in the redness values during storage. Redness values of CON vacuum-packaged samples decreased (P < 0.01) with time, whereas those for the SUP products only tended to decrease. The redness values of FOG-packed ham were higher than those of VAC-packed ham at the end of the display period, irrespective of the dietary group. Overall, colour appeared to be more stable in the FOG-packed products than in the VAC-packed products. It can be concluded that dietary supplementation of bulls with vitamin E appears to offer only a minor improvement in colour stability over current feeding regimens when the Mm. semitendinosus are used to make cured, pasteurized ham-type products.     

Effects of previous diet and duration of soybean oil supplementation on light lambs carcass composition, meat quality and fatty acid composition

Forty Merino Branco ram lambs were used to study the effects of initial diet and duration of supplementation with a conjugated linoleic acid (CLA) promoting diet, on carcass composition, meat quality and fatty acid composition of intramuscular fat. The experimental period was 6 weeks. The experimental design involved 2 initial diets (commercial concentrate (C); dehydrated lucerne (L)), and 2 finishing periods (2 and 4 weeks) on dehydrated lucerne plus 10% soybean oil (O). Data were analysed as a 2 × 2 factorial arrangement with initial diet and time on finishing (CLA promoting) diet as the main factors. The lambs were randomly assigned to four groups: CCO; COO; LLO; LOO according to the lamb’s diet fed in each period.Lambs initially fed with concentrate showed higher hot carcass weights (11.2 vs 9.6 kg) than lambs fed initially with lucerne. The increase of the duration of finishing period reduced the carcass muscle percentage (57.4% vs 55.5%) and increased the subcutaneous fat percentage (5.67% vs 7.03%). Meat colour was affected by initial diet. Lambs initially fed with concentrate showed a lower proportion of CLA (18:2cis-9, trans-11 isomer) (0.98% vs 1.38% of total fatty acids) and most of n−3 polyunsaturated fatty acids than lambs initially fed with lucerne. Initial diet did not compromise the response to the CLA-promoting diet and the proportion of 18:2cis-9, trans-11 in intramuscular fat increased with the duration of time on the CLA-promoting diet (1.02% vs 1.34% of total fatty acids).     

Effects of breed and a concentrate or grass silage diet on beef quality in cattle of 3 ages. II: Meat stability and flavour

This study examined the effect of breed and diet on meat quality, defined as lipid stability, colour shelf life and sensory quality. Ninety-six steers were used, half Aberdeen Angus (AA) cross and half Holstein-Friesian (HF). They were reared from 6 months of age on a standard concentrate diet or grass silage and slaughtered at 14, 19 or 24 months of age. Breed had small effects on quality with lower lipid stability in muscle of 24 month-old HF (P<0.05). Sensory scores were similar between the breeds, the few differences being in favour of AA. Diet had the biggest effects on meat quality, in all 3 age groups. The grass silage diet produced higher plasma and muscle levels of vitamin E, lower lipid oxidation in loin steaks measured at 4 and 7 days of retail display and better colour stability (saturation) during shelf life in MAP (O(2):CO(2); 75:25) (all P<0.001). The high values for lipid oxidation in the concentrate-fed steers were linked to high muscle PUFA concentrations and low levels of vitamin E.     

日粮中Zn和Se强化对秦宝雪花牛肝中矿物质及挥发性化合物的影响

为了研究日粮中Zn、Se营养强化对秦宝雪花牛（秦川牛×日本和牛）肝矿物质及挥发性化合物的影响,选取16头秦宝雪花公牛为实验对象,分别以基础日粮、添加Zn、Se营养强化剂的强化日粮进行饲养。在18月龄屠宰后测定其肝脏中的矿物质元素Ca、Fe、Zn、Se、Mg以及挥发性化合物。结果发现Zn、Se强化使秦宝雪花牛肝矿物质元素中的Zn含量提高了73%,并使Se含量提高了18.6倍。苯并噻唑的含量在Zn、Se强化后被提高了15%。此外,Zn、Se强化还会影响到壬醛、反-2-壬烯醛、2-戊基呋喃等物质的含量。结果表明,日粮中Zn、Se强化会提高秦宝雪花牛肝中Zn、Se等矿物质含量,同时会对部分含硫化合物和醛类物质产生明显影响。      

Effect of genetic origin, diet and weaning weight on carcass composition, muscle physicochemical and histochemical traits in the rabbit

Fifty rabbits originating from the crossing of one dam strain with three sire strains, Hy+, INRA 9077 and INRA 3889, were studied. The adult body weights of the sire strains were 5·1, 4·1 and 3·1 kg, respectively. After weaning, the Hy+ and the INRA 9077 rabbits were fed either an H (11·99 MJ DE kg DM⁻¹) or L diet (9·67 MJ DE kg DM⁻¹). The INRA 3889 rabbits were fed only the H diet. In each of these five blocks, two weaning weights were studied and the rabbits were slaughtered when the average body weight of each block reached 2·5 kg. Slaughter yield, carcass fatness and hindleg meat to bone ratio were determined. Muscular tissue was described using (1) physicochemical criteria (ultimate pH, L^*a^*b^* colour) of the biceps femoris (BFE), tensor fasciae latae (TFL) and semimembranosus accessorius (SMA) muscles and (2) histochemical characteristics of the longissimus lumborum muscle (LL) through computerised image analysis (fibre type composition, cross-sectional area). At slaughter, the rabbits of INRA 3889 sire origin, which had the highest degree of maturity (72%), gave the best slaughter yield (p<0·01), the heaviest reference carcass weight (p<0·01), and highest LL proportion (p<0·01), hindleg meat to bone ratio (p<0·05) and fatness (p<0·01); their LL muscle showed the lowest percentage of βR fibres, while the cross-sectional area of their muscular fibres was the highest (p<0·05). When all sire × diet combinations were put together, the heavier the weaning weight, the lower the daily gain (p<0·01) and the lightness (L*) of thigh muscles (p<0·05). The lower the DE content of the diet, the lower the growth rate, the slaughter yield, the reference carcass weight (p<0·01) and the cross-sectional area of all types of muscle fibres of the rabbits of both Hy+ and INRA 9077 sire origin.     

Addition of tea catechins and vitamin C on sensory evaluation, colour and lipid stability during chilled storage in cooked or raw beef and chicken patties

The effects of addition of tea catechins (TC) and vitamin C (VC) on sensory evaluation, colour and lipid stability in cooked or raw beef and chicken meat patties during refrigerated storage were studied. Fresh beef striploin and chicken breast muscles were minced, following removal of external fat and connective tissue. Following mincing, beef and chicken were assigned to one of the following five treatments: control (meat treated with no antioxidant); TC200, meat plus 200 mg TC/kg muscle; TC400, meat plus 400 mg TC/kg muscle; VC200, meat plus 200 mg VC/kg muscle, VC400, meat plus 400 mg VC/kg muscle. Sodium chloride (1%) was added to all samples. Patties (125 g portions), formed from the above-treated minced meat, were oven cooked, cooled, and packaged in 30% CO₂:70% N₂. Fresh raw beef and chicken patties were packaged in 80% O₂:20% CO₂. All samples were stored for up to 7 days under fluorescent lighting at 4 °C. Sensory parameters (colour, flavour, taste, tenderness and overall acceptability) were evaluated on cooked beef and chicken patties after 1, 3 and 6 days of storage. Surface colour (Hunter L, a and b values), and lipid oxidation (2-thiobarbituric acid reactive substances) were measured on days 1, 3 and 6 of storage for cooked meats and on days 2 and 7 for raw beef and chicken. Tea catechins addition (200 or 400 mg/kg) to minced meat caused (P < 0.05) discolouration in cooked beef and chicken meat patties and significantly reduced (P < 0.001) lipid oxidation in cooked or raw beef patties compared to the control. Beef, either raw or cooked, was more susceptible (P < 0.01) to oxidation compared to chicken. Raw meat stored in high oxygen conditions was more susceptible to lipid oxidation than cooked meat stored in anaerobic conditions. Tea catechins treatments (TC200 and TC400) inhibited (P < 0.05) lipid oxidation in raw beef to a greater extent than vitamin C treatments (VC200 and VC400). These results indicate that tea catechins are potent natural antioxidants and exhibit greater antioxidant efficacy compared to vitamin C.     

食物中维生素A、叶酸和维生素E分析方法研究进展

对食物中 3种重要的维生素 :维生素A、叶酸和维生素E的常用分析方法进行了综述。指出了不同分析方法的适用范围以及各自的优缺点。着重介绍了高效液相色谱法在此 3种维生素分析中的应用。并提出了分析方法的发展趋势是高效液相色谱法 (包括正相高效液相色谱法、反相高效液相色谱法和非水反相高效液相色谱法 )、高效液相 -质谱法、气相色谱 -质谱法和离子色谱-质谱法等方法。     

Effect of vitamin E supplementation on weight gain, immune competence, and disease incidence in barley-fed beef cattle

The aim of the study was to investigate whether vitamin E supplements in larger amounts than recommended could reduce incidence of disease, improve immune competence, and increase rate of weight gain of conventionally barley-fed beef cattle. Mean daily intake of vitamin E by individual calves in the experimental group was 200 mg during the first 2 mo, 400 mg during the next 2 mo, and 600 mg during the rest of the period. Corresponding daily intakes of vitamin E for the control group were 50, 100, and 150 mg. Mean plasma vitamin E of the experimental group increased from .49 mg/L at the start of the trial to 2.03 mg/L at the end, but that of the control group was lower at the end (.36 mg/L) than at the beginning (.53 mg/L). No significant differences were observed between the groups concerning incidence of disease or magnitude of lymphocyte stimulation. The results indicated that there was a surprisingly poor biological availability of the dietary vitamin. Therefore, a comparison in reality was made between calves with inadequate and normal vitamin E status. The differences in daily BW gain and time to reach slaughter weight thus probably were effects of the low vitamin E status rather than positive effects of additional vitamin in the diet.     

Chloride salt type/ionic strength and refrigeration effects on antioxidant enzymes and lipid oxidation in cattle,camel and chicken meat

The effects of NaCl and KCl at varying ionic strengths on catalase and glutathione peroxidase (GSH-Px) activities and lipid oxidation in ground Longissimus dorsi (LD) of cattle and camel and breast muscle of chicken during refrigerated storage were studied. NaCl and KCl significantly increased 2-thiobarbituric reactive substances (TBARS) and peroxide values. TBARS and peroxide values increased and GSH-Px activity decreased during 4 day storage in the 4 °C, but catalase activity was stable. Salt type had no consistent effect on GSH-Px and catalase activities. Chicken samples had lower enzyme activities and TBARS content than cattle and camel. Their peroxide values were lower than camel samples. Camel meat showed higher catalase activity and TBARS content than cattle meat. Results indicated that negative correlation between lipid oxidation and GSH-Px activity and the accelerated lipid oxidation in salted meat may be partly related to a decrease in GSH-Px activity.     

Effect of antioxidant on the fatty acid composition and lipid oxidation of intramuscular lipid in pressurized pork

To investigate the effect of antioxidants on lipid oxidation and fatty acid composition in pressurized pork, minced pork with or without 1% Na(2)EDTA was pressurized at 500MPa before 7days storage at 4°C. TBARS value, lipid content and fatty acid composition in untreated and high-pressure (HP) treated samples were analyzed. HP treatment induced marked increases in TBARS values and lipolysis of partial phospholipids causing an increase of free fatty acid content. Preferential hydrolysis for polyunsaturated fatty acids (PUFA) in phospholipids resulted in the percentage of PUFA in phospholipids decreasing markedly and thereby that in free fatty acids increasing significantly. Addition of 1% Na(2)EDTA to minced pork before HP significantly decreased the TBARS values in pressurized samples, but did not inhibit the lipolysis of phospholipids, causing the fatty acid composition of phospholipids and free fatty acids to change similarly to those samples without Na(2)EDTA.