紫茎泽兰对建昌黑山羊肌肉中氨基酸和脂肪酸含量的影响

为研究紫茎泽兰(Ageratina adenophora)对建昌黑山羊肌肉中氨基酸和脂肪酸含量的影响,本研究采用氨基酸自动分析仪和氯仿–甲醇抽提法,对自然放牧采食紫茎泽兰的建昌黑山羊背最长肌中氨基酸、脂肪酸含量进行测定分析。结果显示,与对照组比较,建昌黑山羊肌肉必需氨基酸(essential amino-acid,EAA)、非必需氨基酸(non-essential amino acid,NEAA)和总氨基酸(total amino acid,TAA)含量减少,风味氨基酸含量减少;饱和脂肪酸(saturated fatty acid,SFA)含量减少,单不饱和脂肪酸(monounsaturated fatty acid,MUFA)、多不饱和脂肪酸(polyunsaturated fatty acids,PUFA)和不饱和脂肪酸(unsaturated fatty acid,UFA)含量增加,UFA/SFA(U/S)值升高,与膻味呈正比的脂肪酸含量升高,与膻味呈反比的脂肪酸含量减少,说明紫茎泽兰降低了肉品的氨基酸营养价值,增加了肉品的脂肪酸营养价值,对肉品风味有一定影响。研究表明,紫茎泽兰饲喂反刍动物,具有一定的营养价值,但紫茎泽兰的毒性使动物肌肉脂肪酸和氨基酸含量发生变化,降低了肉品品质。     

Effects of dietary phytol on tissue accumulation of phytanic acid and pristanic acid and on the tissue lipid profiles in mice

Recent in vitro evidence suggests that the phytol‐derived fatty acids, phytanic acid (PA) and pristanic acid (PrA), are components of animal products with the potential to cause both beneficial and harmful effects on human health. In this study, we investigated the in vivo tissue accumulation of PA and PrA and the changes in tissue lipid profiles, using mice fed a phytol‐containing diet. After 4 weeks of treatment with a diet containing 1.0% phytol, plasma, adipose tissue, liver, and brain were collected and their lipid profiles were biochemically and gas‐chromatographically determined. Dietary phytol caused PA and PrA accumulation in the adipose tissue and liver but not in the brain, and reduced plasma and liver triacylglycerol levels. Phytol intake also decreased the fatty acid concentrations in the adipose tissue, especially polyunsaturated fatty acids such as linoleic acid, but increased the concentrations of these fatty acids in the liver. However, dietary phytol had a low impact on the brain lipid profile. This study suggests that dietary phytol intake caused accumulation of PA and PrA and modified lipid profiles in the adipose tissue and liver, but that the brain is an insusceptible tissue to dietary phytol‐induced changes.     

3种植物添加剂对惠阳胡须鸡肌肉氨基酸、脂肪酸组成与含量的影响

本试验旨在研究绿茶粉、桑叶粉和大蒜粉对鸡肌肉中氨基酸、脂肪酸含量和组成的影响，为植物添加剂在惠阳胡须鸡生产中的应用提供理论依据。选取120只120日龄体重相同、健康的惠阳胡须母鸡，随机分成4个处理，每个处理3个重复，每个重复10只。试验Ⅰ组，饲喂基础日粮+2%绿茶粉；试验Ⅱ组，饲喂基础日粮+4%桑叶粉；试验Ⅲ组，饲喂基础日粮+1.5%大蒜粉；对照组，饲喂基础日粮，预试验7 d，正式试验30 d。饲养试验结束后，每个处理随机选取10只鸡进行屠宰。每只屠宰鸡取同一部位胸肌100 g，通过氨基酸自动分析仪测定肌肉中氨基酸的组成和含量，通过气相色谱仪测定肌肉中脂肪酸的组成和含量。试验结果表明：①日粮中添加植物添加剂对肌肉中氨基酸的组成没有影响，但对肌肉中氨基酸的含量有影响，试验组必需氨基酸含量均显著高于对照组（P<0.05）；②日粮中添加植物添加剂对肌肉中脂肪酸的组成没有影响，但对肌肉中脂肪酸的含量有影响，对照组总饱和脂肪酸含量显著高于3个试验组（P<0.05），而3个试验组总多不饱和脂肪酸含量/总饱和脂肪酸含量的比值显著高于对照组（P<0.05）。本试验结果表明，日粮中添加植物添加剂不影响肌肉中氨基酸和脂肪酸的组成，但影响肌肉中两者的含量，显著降低鸡肌肉中饱和脂肪酸的含量，提高多不饱和脂肪酸的比例，增加必需氨基酸含量。因此，日粮中添加植物添加剂可改善惠阳胡须鸡肌肉品质。     

Comparison of amino acid profiles between rats subjected to forced running and voluntary running exercises

It has been suspected that in comparison with glucose or fatty acids, the levels of amino acids may readily change with different forms of exercise. In the present study, we measured the concentrations of amino acids, glucose, triglycerides, total protein and total cholesterol in the blood and/or cerebrospinal fluid (CSF) of rats subjected to forced running exercise on a treadmill, and voluntary running exercise using a wheel, with a constant running distance of 440 m. Rats that performed no running and rats subjected to immobilization stress were used as controls. We observed a few significant changes in the levels of plasma glucose, triglycerides, total protein and total cholesterol in all groups. Whereas, plasma amino acid levels were significantly changed by exercise and stress, especially during the light period. The plasma levels of many amino acids were specifically increased by forced running; some were decreased by immobilization stress. Few amino acids showed similar changes in their levels as a result of voluntary running. In addition, there was a significant difference in the degree of amino acid imbalance between blood and CSF. These results provide the first information on changes in levels of amino acids in plasma and CSF resulting from forced and voluntary exercises.     

Fatty acid composition of serum lipids in atopic and healthy dogs

Fatty acids are increasingly used in the treatment of canine atopic dermatitis and their beneficial effects are documented in several prospective, controlled studies. Results from recent studies have indicated that atopic dogs have disordered fat metabolism, due to decreased desaturase activity. To further clarify these possible abnormalities, we examined serum fatty acid patterns in dogs with atopic dermatitis and normal controls. Atopic dermatitis was diagnosed according to the diagnostic criteria proposed by Willemse, after elimination of other possible causes of pruritic dermatitis. Both the relative and the absolute amounts of fatty acids in sera were determined by gas chromatography. Differences in the serum fatty acid pattern indicating a reduction in desaturase activity were not detected in atopic dogs when compared with controls.     

低温弱光胁迫下芸豆叶片光抑制与类囊体膜脂构成变化

以对低温弱光敏感性有差异的两个红芸豆品种为材料,研究了低温弱光胁迫处理及恢复过程中幼苗叶片的叶绿素含量、荧光参数和类囊体膜脂肪酸组成的变化。结果表明:与对照相比,随胁迫时间延长,叶片中Chl a、Chl b和Chl(a+b)含量降低(P<0.05);F_v/F_m、F_v'/F_m'、qP、Φ_PSⅡ和ETR下降(P<0.05),Chl a/b和NPQ上升(P<0.05);类囊体膜脂MGDG、DGDG和SQDG中的亚麻酸(C18:3)含量显著降低(P<0.05),棕榈酸(C16:0)含量显著升高(P<0.05),PG中的棕榈酸(C16:0)和反式十六碳-烯酸[C16:1(3t)]含量降低(P<0.05),而亚麻酸(C18:3)和亚油酸(C18:2)含量升高(P<0.05),在叶片抵御低温弱光胁迫过程中维持一定的膜脂不饱和度的重要作用。随胁迫时间延长,类囊体膜总饱和脂肪酸(SFA)含量升高,多不饱和脂肪酸(PUFA)含量以及膜脂不饱和度(U/S)显著降低,恢复期则相反。在胁迫处理和恢复期,“英大红”和“小红芸豆”的U/S变化差异不明显,PUFA含量变化差异显著(P<0.05),且与F_v/F_m的相关性分别达到86.21%和83.92%,表明低温弱光处理及恢复过程中,光抑制后PSⅡ功能的修复与PUFA含量增加存在一定关系。因此,低温弱光胁迫下“英大红”光抑制程度较“小红芸豆”轻,可能是较高含量的PUFA增加了类囊体膜的不饱和度,维持膜的稳定性,减轻了光抑制。     

Effect of SCD and SREBP genotypes on fatty acid composition in adipose tissue of Japanese Black cattle herds

Fatty acid composition of beef adipose tissue is one of important traits because high proportions of monounsaturated fatty acid are related to favorable beef flavor and tenderness. In this study, we investigated effects of genetic factors such as stearoyl-CoA desaturase (SCD) and sterol regulatory element binding protein (SREBP) on beef carcass traits including fatty acid composition using two cattle populations. Sire effect was significantly related to almost all traits except BMS, suggesting that the trait examined in this study is highly controlled by genetic factors. The effect of SCD genotype on fatty acid composition was detected remarkably in both cattle groups, especially on stearic and oleic acids. This result was consistent with our previous studies and suggests that SCD is associated with fatty acid composition. Unlike SCD genotyping, the effect of SREBP genotype was not identified in this study. Our results suggested that SCD genotype would contribute to improving beef quality in field populations. Further studies about the relationship among these factors will bring an insight into the molecular mechanism of fatty acid metabolism in cattle.     

Effect of Slaughter Weight on Carcass Traits,Meat Quality,Amino Acids and Fatty Acids in Muscle of Jiangkou Luobo Pigs

In order to study the effect of slaughter weight on carcass traits,meat quality,amino acids and fatty acids in muscle of Jiangkou Luobo pigs,36 Jiangkou Luobo pigs (6 pigs of 60,70,80,90,100 and 110 kg body weight,respectively) were selected to determine carcass quality,meat quality characteristics and nutritious component and analyze their changes with weight.The results showed that before the body weight reaching to 80 kg,the slaughter rate and loineye area were increased fast,the contents of various amino acids were increased obviously.And when the body weight was 80 kg,the fatty acids were rich,including oleic acid and linoleic acid.When the body weight was more than 90 kg,there were excessive fat deposition in porcine somatic and the content of lysine,valine,threonine and other essential amino acids were extremely significant or significant differences (P<0.05;P<0.01).Generally Jiangkou Luobo pigs with the 80 kg body weight had the better carcass traits and meat quality,rich and ideal amino acid and fatty acid composition in muscle,especially had the high content of essential amino acids and flavor amino acid,and suitable proportion of unsaturated fatty acid and saturated fatty acid.Therefore,the reasonable slaughter weight of Jiangkou Luobo pigs was about 80 kg.     

Fatty acid composition,fat deposition,lipogenic gene expression and performance of broiler fed diet supplemented with different sources of oil

The present study assessed the effect of feeding palm oil (PO), sunflower oil (SO) and their combination on performance, fat deposition, fatty acid composition and lipogenic gene expression of broilers reared for 42 days. A total of 144 1‐day‐old broilers (Cobb500) were randomly allotted into four treatment diets with each having six replicates of six chicks in each replicate following a completely randomized design. Live weight gain and feed efficiency was significantly (P < 0.05) higher in birds fed with a combination of oil sources compared to controls. Birds fed with the combination of oil and SO alone had higher carcass yield and lower abdominal fat. Higher (P < 0.05) concentrations of unsaturated fatty acids (UFA) and lower concentrations of palmitic acid and saturated fatty acid (SFA) was found in birds fed SO alone and combinations of SO and PO. Furthermore, the outcomes showed that birds fed diet supplemented with SO and the combination of SO and PO down‐regulated gene expression of key hepatic lipogenic enzymes of fatty acids synthase (FAS), acetyl‐CoA carboxylase (ACC) and stearoyl‐CoA desaturase (SCD). These findings suggest that the diet containing the combination of 2% PO and 4% SO may reduce hepatic lipogenesis, as well as lower abdominal fat content of broilers.     

不同屠宰体重对江口萝卜猪胴体性状、肉品质、氨基酸和脂肪酸的影响

为研究不同屠宰体重对江口萝卜猪胴体性状、肉品质、氨基酸及脂肪酸的影响,本研究选取60、70、80、90、100、110 kg各6头江口萝卜猪测定了其不同体重阶段的胴体品质和肉质特性,以分析其胴体性状、肉品质及肌肉营养成分随体重的变化规律。结果显示,江口萝卜猪在体重达80 kg之前,其屠宰率、眼肌面积随体重的增加增长较快,氨基酸的含量增加明显,80 kg时肌肉中含有丰富的脂肪酸种类,其中油酸、亚油酸等不饱和脂肪酸含量较高。江口萝卜猪在体重达90 kg之后脂肪过多沉积,各体重组赖氨酸、缬氨酸、苏氨酸等必需氨基酸的含量呈显著或极显著差异（P<0.05;P<0.01）。总体上看,江口萝卜猪在体重达80 kg左右时其胴体性状及肉质性能较好,肌肉中氨基酸和脂肪酸含量丰富,且具有理想的氨基酸和脂肪酸构成,尤其是必需氨基酸及鲜味氨基酸含量高,不饱和脂肪酸及饱和脂肪酸构成比例适宜。因此,综合各项测定指标江口萝卜猪在体重达80 kg左右屠宰较优。     

两种处理工艺对蚕蛹品质影响的研究

 试验采用正已烷处理法(S2)和水煮处理法(S3)两种工艺对蚕蛹粉(silkworm pupae meal,SM)进行脱脂处理,以未经任何处理的蚕蛹粉(S1)为对照,通过比较三种蚕蛹粉物理性状、常规营养成分、氨基酸组成及必需氨基酸评分和脂肪酸组成,评价两种处理工艺对蚕蛹品质的影响。结果表明,正己烷处理的蚕蛹粉无臭,无色,容重、粗蛋白、粗灰分含量显著提高(P<0.05),粗脂肪含量显著降低(P<0.05),水煮处理法对蚕蛹粉脱脂和脱色效果甚微(P> 0.05),但有除臭效果。正己烷处理后显著提高了蚕蛹粉氨基酸总量、必需氨基酸和鲜味氨基酸含量(P<0.05),且处理后的蚕蛹粉更接近FAO/ WHO 规定的理想蛋白源标准。正己烷处理显著影响蚕蛹粉脂肪酸组成,其中C18∶0、C18∶2n-6水平较其他两组显著提高(P<0.05),C18∶3n-3水平显著降低(P<0.05),C18∶1n-9水平显著低于对照组(S1),但与水煮法组(S3)差异不显著。综上所述,正已烷脱脂不但操作简便,费用低廉,且可以达到除臭、脱色、脱脂、生产优质蚕蛹蛋白粉应用于饲料工业中的目的。     

Stimulatory effect of plasma samples from fattening cattle on adipogenesis‐related gene expression in preadipocyte cells

It is desirable to produce beef with high levels of monounsaturated fatty acids (MUFA), as this is related to fat softness and palatability. However, the physiology of MUFA synthesis in bovine fat during the fattening process remains to be established. In this study, in order to elucidate the relationship between plasma components and the fatty acid composition of intramuscular fat, we investigated the effect of plasma obtained from fattening cattle on the messenger RNA (mRNA) expressions of the adipogenesis‐related gene in a clonal bovine intramuscular preadipocyte line (BIP cells). The mRNA expressions of stearoyl‐CoA desaturase, adipocyte Protein 2, peroxisome proliferator‐activated receptor gamma and sterol regulatory element‐binding protein 1 in BIP cells were significantly higher following treatment with those plasma samples collected from the cattle with the highest diaphragmatic unsaturated fatty acids to saturated fatty acids ratio (US/S). Furthermore, the concentration of nonesterified fatty acid (NEFA) in the plasma samples had an inverse correlation with carcass diaphragmatic US/S. These results indicate that cattle with a low ratio of US/S in fat may be discriminated from the population of fattening cattle before slaughter by measuring the effect of their plasma on gene expression in BIP cells as well as their plasma concentration and composition of NEFA.     

早期断奶对藏西北绒山羊背最长肌氨基酸和脂肪酸含量的影响

[目的] 研究早期断奶对藏西北绒山羊背最长肌中氨基酸和脂肪酸含量的影响。[方法] 将18只健康羔羊按照体重相近原则随机分为试验组和对照组,试验组在28日龄（D28）实施早期断奶,对照组在60日龄（D60）自然断奶,羔羊断奶后饲喂相同的代乳料至75日龄;从两组随机选取5只羔羊进行屠宰采样,对其背最长肌中氨基酸和脂肪酸指标进行测定分析。[结果] 在藏西北绒山羊背最长肌中检测出17种氨基酸,包括赖氨酸、亮氨酸等7种必需氨基酸,天冬氨酸、精氨酸等10种非必需氨基酸。两组断奶羔羊肉中总氨基酸含量、必需氨基酸含量、非必需氨基酸含量均无显著差异（P>0.05）,28日龄断奶组羔羊肉中EAA/TAA、EAA/NEAA比值显著（P<0.05）高于60日龄断奶羔羊。共检测出29种饱和脂肪酸、不饱和脂肪酸,以棕榈酸和油酸含量最高,早期断奶对羔羊肉中饱和脂肪酸含量、单不饱和脂肪酸含量以及多不饱和脂肪酸含量影响不显著（P>0.05）。[结论] 藏西北绒山羊羔羊肉中所含氨基酸和脂肪酸种类多、含量丰富,实施早期断奶、及早补充颗粒料对肉中脂肪酸和氨基酸含量无影响,且可提高EAA/TAA、EAA/NEAA比值,使其更符合FAO/WHO氨基酸评分模式;该试验可为藏西北绒山羊羔羊实施早期断奶、提高母羊的繁殖率提供参考。     

Subcutaneous and intramuscular adipose tissue stearoyl-coenzyme A desaturase gene expression and fatty acid composition in calf- and yearling-fed Angus steers

We proposed that stearoyl-CoA desaturase (SCD) activity dictates fatty acid composition of adipose tissue and muscle in beef cattle, regardless of ruminal or hepatic fatty acid hydrogenation or desaturation. Twelve Angus steers were assigned to a calf-fed (CF) group and slaughtered at weaning (8 mo of age; n=4), 12 mo of age (n=4), or 16 mo of age (n=4). Twelve steers were assigned to a yearling-fed (YF) group and slaughtered at 12 mo of age (n=4), 16 mo of age (n=4), and 17.5 mo of age (n=4; 525 kg, market weight). Data were analyzed based on time on the corn-based finishing diet, with terminal age as a covariate, and orthogonal polynomial contrasts were tested on the main effects of treatment group and time on the finishing diet. Fatty acids from duodenal digesta, plasma, liver, LM, and subcutaneous and intramuscular adipose tissue were measured, and SCD gene expression was measured in intramuscular and subcutaneous adipose tissues. In duodenal digesta, palmitic and linoleic acids increased by 100% over the sampling period, α-linolenic acid decreased over the sampling period, and trans-vaccenic acid was greater in YF than in CF steers (all P < 0.01). The proportion of α-linolenic acid decreased over time in all tissues, including liver. The SCD index (ratio of SCD fatty acid products to SCD fatty acid substrates) increased over time in LM and in intramuscular and subcutaneous adipose tissues. The SCD:glyceraldehyde 3-phosphate dehydrogenase mRNA ratio was virtually undetectable at the initial sampling periods in subcutaneous adipose tissue of YF and CF steers, and it increased over time (P < 0.01). The SCD index and SCD:glyceraldehyde 3-phosphate dehydrogenase ratio were greater in intramuscular adipose tissue of CF steers than in that of YF steers. The SCD index did not change over time in liver and decreased over time in duodenal digesta. We conclude that, unlike essential fatty acids, the SFA and MUFA composition of adipose tissue is regulated by adipose tissue fatty acid desaturation, with little contribution from hepatic or duodenal fatty acids.     

Effects of transcutaneous electrical nerve stimulation on the fatty acid profile of rabbit longissimus dorsi muscle (preliminary report)

This study was designed to investigate whether transcutaneous electrical nerve stimulation (TENS) of the longissimus dorsi muscle (MLD) of rabbits induces specific proportional changes in the muscle fatty acid composition. Ten 4-week-old Pannon White rabbits were exposed to TENS treatment two times a day, with the following settings: 30 Hz, 20 micros impulse length, 10 mA, 2 x 20 min. After a treatment period of 50 days rabbits were slaughtered and the fatty acid composition of the MLD was determined by gas chromatography. The TENS treatment increased the proportions of linoleic (C18:2 n-6), linolenic (C18:3 n-3) and gondoic acids (C20:1 n-9), compared with the control group. The level of palmitic (C16:0), stearic (C18:0), oleic (C18:1 n-9) and eicosapentaenoic (C20:5 n-3) acids significantly decreased. The proportion of total unsaturated fatty acids significantly increased. On the basis of the results obtained, TENS may have similar effects on the muscle fatty acid profile like physical training. Based on the supposal that the composition of membrane structure was also affected, the electrical stimulation of muscles may have further consequences, e.g. on membrane properties.     

低温胁迫对结缕草抗氧化酶活性和脂肪酸含量的影响

为探讨不同纬度来源结缕草（Zoysia Willd）对低温的响应,本研究以两份结缕草种质LT-40（高纬度）和LT-22（低纬度）为材料,分析了适温（30℃/25℃）、亚适温（18℃/12℃）、冷害（8℃/2℃）和冻害（2℃/-4℃）4种温度对叶片电导率（Electrolyte leakage,EL）、叶绿素和丙二醛（Malondialdehyde,MDA）含量、抗氧化酶活性、叶片脂肪酸含量及不饱和指数的影响。结果表明,随着温度的降低,EL增大,叶片中叶绿素含量降低、MDA含量升高,且在LT-22中变化更大;叶片超氧化物歧化酶、过氧化物酶、过氧化氢酶活性均随着温度的下降而逐渐升高,且在LT-40中表现更为显著;低温下叶片中棕榈酸含量呈下降趋势,而硬脂酸含量只在LT-40叶片中显著下降,棕榈油酸和油酸含量在LT-40叶片中显著低于对照,而亚麻酸含量在LT-40叶片中却显著高于对照,不饱和指数在LT-40叶片中显著高于对照。高纬度来源的结缕草在低温胁迫下具有较高的抗氧化能力和较好的质膜稳定性,因而其耐寒性更好。     

Effect of dietary conjugated linoleic acid and monounsaturated fatty acids on productive, carcass and meat quality traits of pigs

Three levels (0, 1 and 2%) of conjugated linoleic acid (CLA) were combined with two levels (low and high) of monounsaturated fatty acids (MUFA) for pig feeding. Productive, carcass and meat quality traits were studied. Large White ♂ × Landrace × Large White ♀ gilts (n = 288) weighting 70 kg were randomly allotted to 6 different feeding treatments and fed to a final average weight of 107 kg. Loins were taken from 48 animals (8 animals randomly selected from each treatment). No differences due to dietary CLA, MUFA or CLA × MUFA interaction were found on average daily gain, average daily consumption, feed conversion ratio, carcass yield, backfat thickness, loin weight, loin pH and loin colour. A significant increase in intramuscular fat content (p = 0.010) and in saturated fatty acids (SFA) (p < 0.001), and a decrease in MUFA (p = 0.001) and desaturase indices were found as consequence of dietary CLA, regardless the MUFA level. Therefore, dietary CLA, MUFA and their interaction did not influence productive and carcass traits of pigs. However, the use of CLA for swine feeding increased the intramuscular fat content and modified the fatty acid profile, regardless the MUFA level of the diets.     

Effects of the fattening period on the fatty acid composition of fat deposits and free amino acid and inosinic acid contents of the longissimus muscle in carcasses of Japanese Black steers

The effects of the fattening period on carcass characteristics, fatty acid composition of fat deposits, and muscle free amino acid (FAA) and inosinic acid (IMP) contents were evaluated in Japanese Black steers. Ten castrated, 10-month-old calves derived from the same sire were divided into five to be slaughtered at the age of 30 months after a 20-month fattening period (20-month group) and five to be slaughtered at the age of 34 months after a 24-month fattening period (24-month group). Concerning the fatty acid composition of subcutaneous fat, the percentage of palmitoleic acid was higher ( P  < 0.05) in the 24- than in the 20-month group, but no difference was noted in any other fatty acids. For intermuscular fat, no difference was observed in any fatty acids. The percentages of oleic acid and total monounsaturated fatty acid of intramuscular and perinephric fat were higher ( P  < 0.05) in the 24- than in the 20-month group. Of the FAAs in the longissimus thoracis muscle, the threonine and tyrosine contents were lower ( P  < 0.05) in the 24- than in the 20-month group. The IMP content was higher ( P  < 0.05) in the 24- than in the 20-month group, suggesting an effect of prolongation of the fattening period.     

Effect of nicotinic acid on the plasma membrane function and polyunsaturated fatty acids composition during cryopreservation in boar sperm

This study was conducted to evaluate the effect of nicotinic acid on plasma membrane integrity and fatty acid composition in frozen–thawed boar sperm. Boar semen was cryopreserved using freezing extender containing nicotinic acid (NA), then plasma membrane integrity, osmotic equilibration, lipid peroxidation and fatty acid were analysed. The plasma membrane integrity of frozen–thawed sperm was significantly higher in the 10 mM NA than in the 0 and 20 mM NA treatment groups (p < 0.05). Additionally, the osmotic equilibration ability was not different in treatment groups, but lipid peroxidation was significantly decreased in the 10 mM NA treatment group (p < 0.05). The saturated fatty acids were significantly decreased in the 10 mM NA treatment group, and C18:1n‐9, C18:2n‐6, C20:4n‐6, C22:5n‐6 and C22:6n‐3, and total polyunsaturated fatty acids (PUFAs) were significantly increased in the 10 mM NA treatment groups (p < 0.05). In summary, 10 mM NA improved plasma membrane integrity, inhibited lipid peroxidation and increased PUFAs in frozen–thawed boar sperm. These results suggest that NA may be useful to protect the plasma membrane and inhibit the loss of PUFAs for sperm cryopreservation in pigs.     

Effect of sire and sex on the intramuscular fatty acid profile and indices for enzyme activities in pigs

In this study, the effect of sire, sex and intramuscular fat content on the intramuscular fatty acid profile, in particular the long chain polyunsaturated fatty acids (PUFA) was investigated. Therefore, pork samples of the Longissimus thoracis were taken from 121 females and castrates that were the progeny of 5 boars. All animals had been fattened on the same diet and were slaughtered at a live weight of approximately 110 kg. Indices for the activities of Δ9, Δ6 and Δ5 desaturase, as well as elongase activity were estimated from ratios of product to precursor fatty acids. Intramuscular fat content was positively related to the total saturated fatty acid proportion (r = 0.376; p < 0.01) and the total monounsaturated fatty acid proportion (r = 0.579; p < 0.01), and inversely correlated with the total PUFA proportion (r = − 0.637; p < 0.01). A significantly higher index for Δ5 and Δ6 desaturase and elongase activity for PUFA metabolism was observed in females compared to castrate males. Sire had a significant effect on the intramuscular fatty acid profile, notably on the total n − 3 PUFA, and on most individual long chain n − 6 and n − 3 PUFA. The cis-9 C18:1/C18:0 index for Δ9 desaturase activity and the cis-11 C18:1/cis-9 C16:1 elongase activity index, as well as the combined desaturase and elongase enzyme activities in both the n − 6 and n − 3 PUFA chains were significantly influenced by sire.