Genotype,production system and sex effects on fatty acid composition of meat from goat kids

Two trials were performed to assess the meat fatty acid profile of goat kids from different genotypes, production systems and sex. In the first trial, genotype effect was determined in 24 suckling male kids from Turkish Saanen, Maltese and Gokceada breeds. In the second trial, male and female Gokceada Goat kids were used to compare the effect of extensive and semi‐intensive production systems on fatty acid composition of meat. Significant genotype effect was observed in the percentages of myristic acid (C14:0), palmitic acid (C16:0), oleic acid (C18:1 n‐9), linolenic acid (C18:3 n‐3), arachidonic acid (C20:4 n‐6) and docosahexaenoic acid (C22:6 n‐3), despite no differences on the ratios of polyunsaturated fatty acids to saturated fatty acids (PUFA/SFA) and n‐6/n‐3 (P > 0.05). The effect of production system had also significant effects on fatty acids, but sex only influenced significantly stearic acid (C18:0), C18:1 n‐9 and C18:3 n‐3 fatty acids and total PUFA level and PUFA/SFA ratio. This study confirms that dairy breeds are prone to produce higher levels of unsaturated fatty acids in their muscle. Meanwhile, meat from Gokceada goat kids, which is one of the indigenous breeds in Turkey, had similar PUFA/SFA and n‐6/n‐3 ratios to Turkish Saanen and Maltase.     

黑白花兔肌肉营养成分分析与评价

为了探讨黑白花兔肌肉营养品质特性,试验按照国家食品安全标准和化学分析法,对黑白花兔肌肉（腿肌）常规营养成分、氨基酸和脂肪酸构成比例进行测定分析,并评价其蛋白质营养价值。结果显示,黑白花兔肌肉中水分、粗蛋白质、粗脂肪和灰分含量分别为73.43%、21.67%、3.83%和1.13%,公、母兔间常规营养成分无显著差异（P>0.05）;黑白花兔肌肉中总氨基酸、必需氨基酸和鲜味氨基酸含量分别为196.53、78.64和70.80 mg/g;以氨基酸评分（AAS）为标准,第一限制性氨基酸是缬氨酸,第二限制性氨基酸是蛋氨酸+胱氨酸;以化学评分（CS）为标准,第一限制性氨基酸是蛋氨酸+胱氨酸,第二限制性氨基酸是缬氨酸,公、母兔间氨基酸含量均无显著差异（P>0.05）;脂肪酸构成比例中不饱和脂肪酸与饱和脂肪酸比为1.74;除棕榈油酸（C16：1）和亚麻酸（C18：3）外,公、母兔间其余脂肪酸含量均无显著差异（P>0.05）。综上所述,黑白花兔肌肉中蛋白质含量高,鲜味氨基酸和必需氨基酸含量丰富,氨基酸平衡性较好,不饱和脂肪酸含量高于饱和脂肪酸,营养价值较高,具有较好的食用价值。     

Analysis and Evaluation of Nutritional Components of Black-White Rabbit Muscle

In order to measure the nutritional characteristics of Black-White rabbit meat,the nutrient components,the conventional nutrient,amino acid and fatty acid content of leg muscle in Black-White rabbit were tested and analyzed,and the protein nutritional values were evaluated based on the National Food Security Standard and chemical analytical method of product quality. The results showed that the moisture,crude proteins,crude fats and ash in leg muscle of Black-White rabbit were 73.43%,21.67%,3.83% and 1.13%,respectively. There was no significant difference on the nutrient components between female and male rabbits (P>0.05). The total amino acids,essential amino acids and delicious amino acids were 196.53,78.64 and 70.80 mg/g,respectively. According to amino acid score (AAS),the first limiting amino acid of Black-White rabbit was Val and the second limiting amino acid was Met+Cys. However,based on the standard of chemical score (CS),the first limiting amino acid was Met+Cys and the second was Val. Additionally,the ratio of unsaturated fatty acids (UFA) to saturated fatty acids (SFA) was 1.74,and no significant difference was found on the amino acids between female and male rabbits (P>0.05). More specifically,except the fatty acid of C16:1 and C18:3, there was no significant difference in the fatty acid compositions between female and male rabbits (P>0.05). In conclusion,Black-White rabbit meat was composed of high proteins,delicious amino acids and essential amino acids suggesting that it had better balance of amino acids. The unsaturated fatty acids in Black-White rabbit meat were higher than saturated ones meaning high nutritional value and better dietary values.     

陇东黑山羊肉品质及脂肪酸特征研究

为分析陇东黑山羊肉品质及脂肪酸特性,本研究在庆阳市随机选取3只12月龄陇东黑山羊公羊,测定其肉品质、营养成分和肌内脂肪酸。结果表明:背最长肌的pH在5.67～6.22,属于鲜肉的正常范围,剪切力为71.74 N,熟肉率为56.37%,肉色评分为3.33;背最长肌的水分含量(73.82%)高于前腿肌和后腿肌(P<0.05),背最长肌和前腿肌中的粗脂肪含量高于后腿肌(P<0.05),粗灰分和粗蛋白质含量在3个肌肉组织中差异均不显著;3个肌肉组织中单不饱和脂肪酸含量高于多不饱和脂肪酸(P<0.05),其中背最长肌中的油酸(C18:1n9c)含量为27.00%;多不饱和脂肪酸与饱和脂肪酸的比值(PUFA/SFA)在背最长肌中的含量为0.33。综合分析,胴体不同部位间营养成分和脂肪酸的组成及含量有一定差异性,背最长肌肉质最优,具有较好的食用价值和生产高档羊肉产品的潜力。     

草地早熟禾叶片脂肪酸对秋季低温的响应

为了探索冷季型草坪草的耐冷机制,以气相色谱-质谱（GC-MS）对秋季草地早熟禾叶片脂肪酸进行测定,并与盛夏时作对比。利用NIST97.L质谱库共检索出27种脂肪酸,以棕榈酸和硬脂酸为主的饱和脂肪酸有13种,约占总数的17%;以亚麻酸、亚油酸和棕榈油酸为主的不饱和脂肪酸有14种,约占83%。此外,肉豆蔻酸、棕榈酸、油酸等12种脂肪酸始终存在,占98.2%～99.2%,是质膜的主要组分。随气温降低,脂肪酸种类和含量都发生了改变。盛夏有反丁烯二酸和十四炔酸,而入秋后出现了苯甲酸、月桂酸、癸酸等12种脂肪酸,但含量甚微;此外,二烯脂肪酸下降,三烯脂肪酸增加。研究结果表明,草地早熟禾叶片质膜含有较高的不饱和脂肪酸,具有较强的耐冷性;为了抵御秋季冷凉气温,其脂肪酸不饱和度进一步增加更是提高了对冷害的抗性。     

反刍动物肌肉脂肪酸对肉品质的影响及其调控因素

肌肉中脂肪酸的含量和组成成分在一定程度上影响肉品质以及消费者的健康。反刍动物的肉产品是具有保健作用的共轭亚油酸的主要来源。因此,揭示反刍动物肌肉脂肪酸的形成机制与调控手段十分必要。本文主要针对反刍动物肌肉脂肪酸的调控因素及肌肉脂肪酸对肉质风味、氧化稳定性和肉色的影响进行了综述,以期为改善反刍动物肌肉脂肪酸提供参考。     

Effect of soy lecithin on total cholesterol content,fatty acid composition and carcass characteristics in the Longissimus dorsi of Hanwoo steers (Korean native cattle)

This study aims to investigate the effect of soy lecithin on the total cholesterol content, the fatty acid composition and carcass characteristics in the Longissimus dorsi in Hanwoo steers. Hanwoo steers (24 head) were fed two diets: Control (CON) (concentrate + alcohol‐fermented feed (AFF)) and soy lecithin treatment (CON + soy lecithin at 0.5% of the AFF). Soy lecithin treatment increased average daily gain, serum concentrations of triglyceride, total cholesterol and high‐density lipoprotein‐cholesterol in the blood. A lower cholesterol concentration was found in the Longissimus dorsi for the soy lecithin diet compared to the CON diet. With respect to the marbling score and quality grade of Longissimus dorsi, soy lecithin supplementation significantly increased the C20:5n3, C22:4 and polyunsaturated fatty acids contents compared to the CON diet. Soy lecithin supplementation would alter the total cholesterol content, polyunsaturated fatty acid profile and meat quality of Longissimus dorsi.     

Genetic correlations among fatty acid compositions in different sites of fat tissues, meat production, and meat quality traits in Duroc pigs

This study estimated genetic parameters for fatty acids of different sites of fat tissue, meat production, and meat quality traits of Duroc pigs selected during 7 generations for ADG, LM area, backfat thickness (BF), and intramuscular fat (IMF). For this study, 394 barrows and 153 gilts were slaughtered at 105 kg of BW. High heritabilities for C18:0 of outer and inner subcutaneous fat tissue were estimated, respectively, as 0.54 and 0.51; those of intermuscular and intramuscular fat were 0.40 and 0.51, respectively. Genetic and phenotypic correlations of ADG and BF with saturated fatty acids of outer and inner subcutaneous fat were positive, but those with C16:1 and C18:2 were negative, and those with C18:1 were nearly zero. Genetic and phenotypic correlations between LM area and respective fatty acids showed opposite results. Respective genetic and phenotypic correlations of melting points with C18:0 and C18:1 were positive and high, and negative and high, respectively. Genetic correlations between cooking loss and SFA (C14:0, C16:0, and C18:0) of IMF were positive and moderate: 0.56, 0.47, and 0.47, respectively. On the other hand, monosaturated fatty acid of C18:1 was highly and negatively correlated with cooking loss (-0.61). Moreover, high genetic correlation between meat color (pork color standard and lightness) and fatty acid compositions of IMF suggest that the SFA (C14:0, C16:0, and C18:0) were correlated genetically with meat lightness and that unsaturated fatty acid compositions (C18:1 and C18:2) were correlated with meat darkness. Results of this study suggest that the fatty acid composition of adipose tissue is correlated genetically with meat production and meat quality traits.     

Fatty acid composition, oxidative stability and sensory quality of meat from broiler chicken fed autolysate from bacteria grown on natural gas

Bacterial autolysate, a down stream product of bacterial biomass grown on natural gas by mainly the methanotrophic bacteria Methylococcus capsulatus, was fed at 8% as is to broiler chickens from 1 to 35 days of age for studies of fatty acid composition, lipid oxidation and sensory quality of thigh meat stored frozen for 6 month at -18 °C or -80 °C. Lipid oxidation was measured by thiobarbituric acid reactive substances (TBARS) and volatile profile by dynamic headspace gas chromatography. Adding bacterial autolysate to diets did not affect the total content of saturated, monounsaturated or polyunsaturated fatty acids in thigh meat, but increased the levels of C14:0, C16:0, C18:0 and C16:1n-7 and reduced the levels of C18:1n-7, C18:2n-6 and C18:3n-3 fatty acids. Feeding of bacterial autolysate tended (p < 0.08) to reduce TBARS of meat samples. Contents of volatiles were generally low, but feeding of bacterial autolysate significantly reduced levels of butanal (p < 0.04) and tended to reduce levels of hexanal (p < 0.11), pentanal (p < 0.09), 1-penten-3-ol (p < 0.08) and butanone (p < 0.08). Bacterial autolysate had no effects on sensory quality parameters of meat related to odour and flavour. To conclude, adding bacterial autolysate to diets did not affect the relative proportion of saturated, monounsaturated or polyunsaturated fatty acids, but reduced content of volatiles in frozen-stored broiler meat. The reduced susceptibility to lipid oxidation in broiler meat may be related to antioxidant properties of the bacterial autolysate.     

番鸭产蛋各期肝脂肪酸组成及AMPK信号通路基因表达研究

旨在探究产蛋各期番鸭肝腺苷酸活化蛋白激酶（AMPK）信号通路基因表达和肝脂肪酸组成,为番鸭肝脂质代谢应答产蛋提供机理研究。本研究选取开产前22周龄、产蛋初期30周龄、产蛋中期40周龄和产蛋末期60周龄母番鸭各15羽,全自动生化仪测定血脂水平,苏木精-伊红（HE）染色和油红O染色观察肝组织学结构,实时荧光定量PCR （qRT-PCR）检测肝AMPK通路基因表达,气相色谱-质谱联用法（GC-MS）检测产蛋各期肝脂肪酸组成。结果表明,总胆固醇（TC）、低密度脂蛋白胆固醇（LDL-C）、甘油三酯（TG）和极低密度脂蛋白胆固醇（VLDL-C）水平在40周龄显著高于22、30和60周龄（P<0.05）;高密度脂蛋白胆固醇（HDL-C）水平在30和40周龄显著低于22和60周龄（P<0.05）。肝HE和油红O染色切片显示,肝在22周龄呈实质状,至产蛋40和60周龄,肝脂滴沉积明显（P<0.05）。AMPKα1在22、30、40和60周龄呈本底低水平表达,并显著低于产蛋各期肉碱脂酰转移酶1（CPT1）和脂肪酸合成酶（FAS）的表达量（P<0.05）,FAS在22、40和60周龄均呈高水平表达（P<0.05）;羟甲基戊二酰辅酶A还原酶（HMGR）、肝细胞核因子4α（HNF4α）、乙酰辅酶A羧化酶1（ACC1）和固醇调控元件结合蛋白-1（SREBP1c）在40周龄表达量显著高于22和30周龄（P<0.05）。肝中饱和脂肪酸（SFA）、单不饱和脂肪酸（MUFA）和多不饱和脂肪酸（PUFA）主要由C16∶0、C18∶0、C18∶1和C20∶2 n-6构成,分别占总脂肪酸含量的32%、16%、30%和9%。C14∶0和C16∶0含量在40周龄显著高于22周龄（P<0.05）;C24∶0、C20∶2 n-6和PUFA含量在60周龄显著高于22和40周龄（P<0.05）。综上,番鸭产蛋期肝通过上调FAS等脂质合成基因表达,合成大量长链脂肪酸,沉积于肝,并增加血脂水平。     

Technical note: stearidonic acid metabolism by mixed ruminal microorganisms in vitro

Dietary supplementation of stearidonic acid (SDA; 18:4n-3) has been considered a possible strategy to increase n-3 unsaturated fatty acid content in ruminant products; however, little is known about its metabolism in the rumen. In vitro batch incubations were carried out with bovine ruminal digesta to investigate the metabolism of SDA and its biohydrogenation products. Incubation mixtures (4.5 mL) that contained 0 (control), 0.25, 0.50, 0.75, 1.00, 1.25, or 1.50 mg of SDA supplemented to 33 mg (DM basis) of commercial total mixed ration based on corn silage, for dairy cows, were incubated for 72 h at 39°C. The content of most fatty acids in whole freeze-dried cultures was affected by SDA supplementation. Branched-chain fatty acids decreased linearly (P < 0.01), and odd-chain fatty acids decreased quadratically (P < 0.01), particularly from 1.00 mg of SDA and above, whereas most C18 fatty acids increased linearly or quadratically (P ≤ 0.04). Stearidonic acid concentrations at 72 h of incubation were very small (<0.6% of total fatty acids and ≤0.9% of added SDA) in all treatments. The apparent biohydrogenation of SDA was extensive, but it was not affected by SDA concentration (P > 0.05). Biohydrogenation followed a pattern similar to that of other C18 unsaturated fatty acids up to 1.00 mg of SDA. Stearic acid (18:0) and vaccenic acid (18:1 trans-11) were the major fatty acids formed, with the latter increasing 9-fold in the 1.00 mg of SDA treatment. At greater inclusion rates, 18:0 and 18:1 trans isomers decreased (P ≤ 0.03), accompanied by increases in unidentified 18:3 and 18:4 isomers (P = 0.02), suggesting that the biohydrogenation pathway was inhibited. The present results clearly indicate that SDA was metabolized extensively, with numerous 18:4 and 18:3 products formed en route to further conversion to 18:2, 18:1 isomers, and 18:0.     

复合型植物提取物对三黄鸡肉品质的影响

本试验旨在研究日粮中添加不同比例的复合型植物提取物对三黄鸡肉品质的影响。试验选用1日龄,健康、初始体重为29.21 g的三黄鸡公鸡240只,随机分4组,每组10个重复,每个重复6只鸡。A组饲喂基础日粮,B、C、D组在基础日粮中分别添加0.01%、0.02%、0.04%的植物提取物。饲养至70日龄时进行屠宰试验,分别取胸肌、腿肌,测定物理指标、化学指标、氨基酸含量、脂肪酸含量。结果表明:与对照组相比,饲料中添加0.02%的植物提取物能够提高肌肉pH、粗蛋白比例(P0.05),降低肌肉脂肪(P0.05),但对肌肉剪切力无显著差异(P0.05);增加肌肉中苏氨酸、谷氨酸、甘氨酸、亮氨酸、必需氨基酸、呈味氨基酸、总氨基酸含量(P0.05);提高腿肌中饱和脂肪酸、不饱和脂肪酸、必需脂肪酸含量(P0.05)。综合分析,在饲料中添加0.02%的植物提取物能显著改善肌肉风味,提高肌肉品质。     

The effect of dietary fish oil soapstock on the performance,carcass fat and flavour of broilers 1

Three hundred and thirty six male broilers were fed on diets containing two levels (2% and 4%) of either acidulated soybean oil soapstock (SOS), acidulated fish oil soapstock (FOS), or a combination of the two. Some of the replicates were changed from FOS diets to diets containing 4% SOS at 5 or 6 1/2 weeks of age.

Dietary FOS was slightly, but significantly, inferior to SOS with regard to live performance, apparently due to an adverse effect on food intake. All birds fed on FOS were unpalatable due to a pronounced “fishy” flavour, thigh meat being more objectionable than breast meat and cooked broth more than roasted meat. About 3 to 4 weeks after transfer to SOS diets, the broilers were acceptable.

Both soapstocks contained over 65% free fatty acids, but their fatty acid composition differed, with the FOS containing more C₁₂ to C₁₆ saturated fatty acids, palmitoleic acid and the typical long‐chain polyenoic fatty acids, but much less linoleic acid. These patterns were reflected in the total dietary lipids and in the abdominal adipose tissue. After the type of dietary soapstock was altered, there was a gradual change in the composition of body fat, which, after about 3 weeks, approached the fatty acid pattern of the birds fed on a diet containing 4% SOS throughout their growing period.     

Detection of central nervous system tissues in meat products: validation and standardization of a real-time PCR-based detection system

Several phenotypic as well as genotypic methods have been published describing the detection of central nervous system (CNS) tissues that are part of the bovine spongiform encephalopathy (BSE) risk material in food products. However, none of these methods is able to differentiate between CNS tissue of the banned ruminant species and tissues of other animal species. A quantitative and species-specific real-time RT-PCR method has been developed that enables the reliable identification of CNS tissues in meat and meat products. This method is based on a messenger (m)RNA assay that uses bovine, ovine and caprine glial fibrillary acidic protein (GFAP) encoding gene sequences as markers. The in-house validation studies evaluated the tissue specificity of up to 15 bovine tissues and the standardization of absolute as well as relative quantitative measurement. The specific amplification of spinal cord and brain tissue GFAP cDNA has been shown previously. In addition, two commercially available ELISA kits were used for the comparative analysis of artificially contaminated minced meat. Small quantities of bovine brain that had been stored over the recommended period of 14 days were examined. The real-time PCR method proved to be suitable for the detection of 0.1% CNS tissue. No false negative results were observed. The quantitative detection of GFAP mRNA using real-time RT-PCR seems a suitable tool in routine diagnostic testing that assesses the illegal use of CNS tissue in meat and meat products. The stability of the selected target region of the GFAP mRNA also allows the detection of CNS tissues after the meat has been processed.     

Influence of oils on the Taihe Silky Fowl production performances and fatty acids composition of the meat*

Focus on the enrichment of eggs and poultry meat with polyunsaturated fatty acids has increased given their important roles in the human health. The inclusion of polyunsaturated fatty acids (especially n‐3 fatty acids, n‐3 FA) is achieved by different biological methods. The objective of this study was to investigate the effects of inclusion of different oils into the feed on the production performances and fatty acids composition of the meat in Taihe Silky Fowl. A total of 80 fowls were selected at 8 weeks and randomly divided into four groups and fed with basal diet, basal diet + 4% fish oil, basal diet + 4% soybean oil and basal diet + 4% palm oil within 3 weeks respectively. The results showed that: the fowls fed with the diet inclusion of 4% fish oil had higher total gain, average daily gain, the second and the third week average daily gain than those in control group (p < 0.05). Also, inclusion of fish oil could improve the content of C22:5 n‐3 and C22:6 n‐3 polyunsaturated fatty acids in the meat significantly compared with the other three groups (p < 0.01). Meanwhile, C18:3 n‐3 and C18:4 n‐3 polyunsaturated fatty acids were also higher than in the other three groups (p < 0.05 and 0.01). Oils Supplementation could enhance C14:0 and C16:0 (p < 0.05) level, but they did not affect the total saturated fatty acids in the meat. Compared with the control group, fish oil inclusion could lower the C18:2 n‐6 level, higher the C18:3 n‐6, C22:4 n‐6 and C22:5 n‐6 polyunsaturated fatty acids in the meat (p < 0.05). Moreover, diets supplied with 4% fish oil reduced the total n‐6 polyunsaturated fatty acids level and enhanced the total n‐3 polyunsaturated fatty acids level in the meat, which resulted in that the ratio of n‐3/n‐6 was improved, and could meet the need of human body.     

High levels of whole raw soybean in diets for Nellore bulls in feedlot: effect on growth performance,carcass traits and meat quality

The objective of this study was to evaluate the effect of whole raw soybean (WRS) in the finishing diet of Nellore cattle on productive performance, carcass traits, meat quality, fatty acid profile of meat, and blood parameters. In a completely randomized design, 52 Nellore bulls (mean body weight ± SD: 380 ± 34 kg) were allotted for 84 days. The animals received the following diets with a forage: concentrate ratio of 40/60: (i) WRS0: control diet without soybean grains; (ii) WRS8: diet containing 8% WRS in dry matter basis; (iii) WRS16: diet containing 16% WRS, and (iv) WRS24: diet containing 24% WRS. At intervals of 28 days, the animals were weighed, muscle and adipose tissue was analysed by ultrasound, and blood samples were collected. The animals were slaughtered on day 85 and liver weight and hot carcass weight were measured during slaughter. The pH and carcass dressing were calculated at 24 h after slaughter. Longissimus dorsi muscle samples were collected for the determination of fatty acid profile of meat, ether extract, tenderness and sensory analysis of meat aged for 14 days. Blood cholesterol content increased linearly with increasing proportion of whole raw soybean grains. The diet did not affect performance or carcass attributes. The WRS8 had the highest shear force values. In fatty acid profile, C14:0 decreased (p = 0.05), whereas 16:1, 20:0 and 20:1 fatty acids increased linearly with increasing proportion of WRS (p < 0.05). However, concentration of conjugated linoleic acid cis 9, trans 11 and 17:0 increased with WRS24 and WRS16. In the sensory analysis, WRS24 was more tender with respect to the other treatments (p < 0.05). Finally, the inclusion of WRS in the finishing diet of feedlot Nellore bulls only evidenced little changes in fatty acid profile and tenderness, in animals fed diets containing 16 or 24% soybean.     

Improving the nutritional quality and shelf life of broiler meat by feeding diets supplemented with fermented pomegranate (Punica granatum L.) by-products

1. Four experimental diets containing 0, 0.5, 1.0 and 2.0% fermented pomegranate by-products (FPB) were supplied to 320d-old broilers to evaluate the effects of FPB on growth performance, nutritional composition, fatty acid profile and oxidative stability of meat.

2. Dietary supplementation of FPB linearly increased the weight gain and feed intake of broilers with linear reduction in feed conversion ratio.

3. The crude protein, iron, magnesium, and sodium content were linearly higher, whereas cholesterol was linearly lower in the breast meat of FPB-supplemented broilers. In thigh meat, linearly lower ether extract and cholesterol with higher moisture was noted in response to increasing levels of FPB.

4. The proportion of saturated fatty acids was both linearly and quadratically lower in breast and thigh meat, whereas those of monounsaturated fatty acids of breast (linear and quadratic) and n-3 fatty acids of breast and thigh (linear) meat was higher in the FPB-supplemented broilers. The n-6/n-3 ratio of breast meat was linearly lower in response to FPB supplementation. The hypocholesterolaemic to hypercholesterolaemic ratio of thigh meat was higher in the FPB-supplemented groups.

5. The thiobarbituric acid reactive substances and pH value were lower in the breast and thigh meat of FPB-supplemented broilers.

6. Thus, additive supplementation of the diet with up to 2% FPB improved the nutritional quality, fatty acid profile and shelf life of broiler meat.     

Substitution of ramie (Boehmeria nivea) for alfalfa in improving the carcass and meat quality of Liuyang Black goats

Ramie (Boehmeria nivea) is noted for the production of a large biomass that has a high protein content and is rich in antioxidants. It may thus serve as a high-quality forage material to replace alfalfa and improve the meat quality of farmed animals. In this study, we evaluated the carcass characteristics and meat quality of goats when 0, 35%, 75%, and 100% of dietary alfalfa was replaced with ramie. Crude protein content (linear, P < 0.0001) and key muscle color values at 24 h after slaughter decreased with increasing ramie levels. The content of most individual amino acids, non-essential amino acids (NEAA), total amino acids (TAA), branched chain amino acids (BCAA), functional amino acids (FAA), and flavor amino acids (DAA) decreased (P < 0.05) with increasing dietary ramie. The diet in which 35% of alfalfa was replaced with ramie yielded meat with the highest amino acid content, whereas the fatty acid profile was unaffected by the inclusion of ramie. These results indicate that ramie could be used as a potential dietary forage resource for goats, and that substituting 35% of alfalfa with ramie, which is equivalent to 126 g/kg DM content, would be optimal in terms of goat meat quality.     

动物产品中多不饱和脂肪酸和其他脂肪酸含量变化及其影响因素

肉、蛋、奶等动物产品和肉、奶制品是单不饱和脂肪酸(MUFA)和多不饱和脂肪酸(PUFA)的重要来源。因此,提高肉及肉制品、蛋、奶及奶制品中不饱和脂肪酸含量有助于提高全民健康水平和生活质量。主要对目前富含不饱和脂肪酸的动物产品质量及影响动物产品中不饱和脂肪酸成分和含量的饲粮、动物性别和年龄以及基因类型等因素作一简要综述,以期为在生产实践中开发相关技术和产品提供理论参考依据。