复方中草药对猪生长性能、屠宰性能、肉品质和免疫功能的影响

试验旨在研究复方中草药对猪生长性能、屠宰性能、肉品质和免疫功能的影响。将60头育肥猪随机分成4组,每组15头猪。对照组、Ⅰ组、Ⅱ组、Ⅲ组分别在基础日粮中添加0、0.5%、1.0%、2.0%的复方中草药。结果显示:与对照组相比,Ⅰ组育肥猪平均日增重、血清免疫球蛋白G(IgG)含量均显著提高(P<0.05),失水率显著降低(P<0.05)。与对照组相比,Ⅱ组、Ⅲ组育肥猪末重、平均日增重、胴体重、胴体斜长、熟肉率、脾脏指数、血清免疫球蛋白A (IgA)含量、IgG含量均显著提高(P<0.05),料重比、背膘厚、剪切力、失水率均显著降低(P<0.05)。与Ⅰ组相比,Ⅱ组、Ⅲ组育肥猪胴体重、胴体斜长、血清IgG含量均显著提高(P<0.05),背膘厚均显著降低(P<0.05)。研究表明,育肥猪基础饲粮中添加1.0%和2.0%的该复方中草药制剂均能改善育肥猪的生长性能、屠宰性能、肉品质和免疫功能,临床应用中选择1.0%作为最适添加剂量。     

饲粮添加艾叶粉对青年期蛋鸭生长性能、抗氧化功能及免疫性能的影响

试验旨在研究饲粮添加不同水平艾叶粉对青年期蛋鸭生长性能、抗氧化功能及免疫性能的影响。试验选取4周龄健康蛋鸭120只，随机分为4组，每组6个重复，每个重复5只。对照组每天饲喂基础日粮，试验Ⅰ、Ⅱ、Ⅲ组在基础日粮基础上分别添加2%、4%和6%的艾叶粉，预试期7 d，正式期35 d。结果显示：(1)与对照组相比，试验Ⅱ、Ⅲ组末重、总增重和平均日增重（ADG）显著升高（P<0.05），试验组料重比（F/G）显著降低（P<0.05）。(2)与对照组相比，试验Ⅰ、Ⅱ组血清白蛋白（ALB）含量显著提高（P<0.05）、血清丙二醛（MDA）含量显著降低（P<0.05），试验Ⅱ组血清总超氧化物歧化酶（T-SOD）活性显著提高（P<0.05）；试验Ⅰ组血清IgG含量显著提高（P<0.05），试验Ⅱ组血清IgA含量显著提高（P<0.05），试验Ⅰ、Ⅱ组血清IgM含量显著提高（P<0.05），其中试验Ⅱ组IgM含量最高。研究表明，在饲粮添加4%艾叶粉可改善青年期蛋鸭的生长发育、抗氧化功能以及免疫性能。     

复方中草药添加剂对湖羊屠宰性能、肉品质及瘤胃组织形态学的影响

为研究基础日粮中添加不同比例的复方中草药对湖羊屠宰性能、肉品质和瘤胃组织形态学发育的影响,试验选择体重相近的30日龄湖羊公羔24只,随机分为3组,每组8只,对照组饲喂基础日粮,试验Ⅰ组、Ⅱ组在基础日粮中分别添加4%和5%的复方中草药添加剂,试验期60 d。结果显示:试验Ⅰ组羊肉剪切力显著低于对照组(P0.05)和试验Ⅱ组(P0.05);试验Ⅰ组与Ⅱ组的胴体GR值、失水率均低于对照组(P0.05),眼肌面积、熟肉率和脾脏重量均高于对照组(P0.05);试验Ⅰ组瘤胃乳头高度和肌层厚度均显著高于对照组(P0.05)和试验Ⅱ组(P0.05)。说明在湖羊基础日粮中添加4%和5%的复方中草药均能提高产肉性能、增加羊肉嫩度、改善机体的免疫功能和促进瘤胃发育,且4%添加量改善效果更为显著。     

中草药复方添加剂对繁殖后期种公鸡血液生化指标的影响

试验将80只50周龄尼克T种公鸡随机分成Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组,每组16只。Ⅰ、Ⅱ组为对照组,分别饲喂基础日粮和基础日粮添加鸡蛋,Ⅲ、Ⅳ、Ⅴ组为试验组,分别在基础日粮中添加1%、2%、3%中草药复方添加剂,研究中草药复方添加剂对繁殖后期种公鸡血液生理生化指标的影响。结果表明,日粮中添加不同水平中草药复方添加剂均能显著提高种公鸡血清总蛋白和球蛋白含量(P<0.01或P<0.05),显著降低谷丙转氨酶和谷草转氨酶活性,显著降低尿酸和甘油三酯含量(P<0.05);血清尿素氮有降低的趋势,但差异不显著;血清高密度脂蛋白有升高的趋势,但差异不显著;各试验组血清总胆固醇含量不同程度降低,其中Ⅳ组显著低于对照Ⅰ组17.19%。     

日粮中添加复方中草药添加剂对产蛋后期蛋用种母鸡繁殖性能和新城疫抗体效价的影响

试验研究了补益类中草药对淘汰蛋用种母鸡繁殖性能和新城疫抗体效价的影响。将360羽72周龄蛋用种母鸡随机分为4组,每组5个重复,每个重复18羽鸡。对照组饲喂基础日粮,试验Ⅰ、Ⅱ、Ⅲ组分别在基础日粮中添加了1%的补益中草药方剂Ⅰ、Ⅱ、Ⅲ,试验期为7周,观察三种方剂对正常淘汰的蛋用种鸡繁殖性能和免疫功能的影响。结果表明:试验Ⅰ、Ⅱ、Ⅲ组和对照组相比产蛋率分别提高2.45%、6.3%、5.1%,差异不显著(P>0.05);破蛋率和对照组相比分别降低了26.1%、26.86%、18.7%,差异不显著(P>0.05);蛋形指数和蛋壳厚度均差异不显著(P>0.05);试验Ⅰ、Ⅱ、Ⅲ组受精率分别比对照组提高了1.58%、4.42%、1.47%,试验Ⅱ组的受精率显著高于对照组(P<0.05);试验Ⅰ、Ⅲ组死精率分别比对照组降低了41.98%、38.93%,差异不显著(P>0.05);试验Ⅰ、Ⅲ组受精蛋孵化率均显著高于对照组(P<0.05),试验Ⅱ组和对照组差异不显著(P>0.05);试验组新城疫抗体效价在大多数时间均比同期对照组高,第1周时,试验Ⅱ、Ⅲ组显著高于对照组(P<0.05);第6周时,试验Ⅲ组显著高于对照组(P<0.05)。     

复方中草药对仔猪免疫功能的效果影响

为了探究复方中草药对仔猪免疫功能的效果影响,试验选择健康、(25±2)日龄的三元杂交仔猪150头,随机分为5组,每组30头,对照组饲喂基础日粮,Ⅰ、Ⅱ、Ⅲ、Ⅳ组分别在基础日粮中添加0.3%、0.4%、0.7%、1.0%的复方中草药。于免疫前1天和免疫后第28天采血测定猪瘟抗体水平和血清中白蛋白、总蛋白、免疫球蛋白Ig M、Ig G及补体C3浓度。结果表明:免疫后第28天添加复方中草药的Ⅰ、Ⅱ、Ⅲ、Ⅳ组仔猪猪瘟平均抗体水平均高于对照组,其中0.4%添加组(Ⅱ组)抗体水平最高,且离散度较小;免疫后第28天血清总蛋白浓度、免疫球蛋白Ig G及补体C3含量Ⅰ、Ⅱ、Ⅲ、Ⅳ组均较对照组提升,其中0.4%添加组(Ⅱ组)的提升程度优于其他各组,且与对照组相比差异显著(P0.05)但血清中Ig M含量Ⅰ、Ⅱ、Ⅲ、Ⅳ组与对照组无明显差异。说明复方中草药可以增强仔猪免疫功能、提升猪瘟抗体水平,且增强及提升的程度与添加剂量有关。     

发酵中草药对黑山羊生长性能及血液生化、免疫和抗氧化指标的影响

试验旨在研究发酵中草药对黑山羊生长性能及血液生化、免疫及抗氧化指标的影响。选取18只健康的努比亚黑山羊,随机分为3组,每组3个重复,每个重复2只羊;对照组饲喂基础饲粮,试验Ⅰ组为基础饲粮+200 g发酵中草药、试验Ⅱ组为基础饲粮+300 g发酵中草药,预试期10 d,正试期60 d。结果显示,试验Ⅰ组和试验Ⅱ组黑山羊的采食量和日增重显著高于对照组(P<0.05);试验Ⅱ组黑山羊血液免疫球蛋白IgA、IgG和IgM均显著高于对照组(P<0.05),且超氧化物歧化酶(SOD)和过氧化氢酶(CAT)显著高于试验Ⅰ组和对照组(P<0.05);对照组丙二醛(MDA)含量显著高于试验Ⅰ组和试验Ⅱ组(P<0.05)。由此可见,基础饲粮中添加发酵中草药能促进黑山羊的生长性能,添加300 g发酵中草药能显著提高机体的免疫力和抗氧化能力。     

复方中草药添加剂对细鳞鱼生长性能的影响

试验研究含大蒜素和杜仲的复方中草药添加剂对细鳞鱼生长性能的影响,进行49 d的饲养试验,试验共设4个处理组:对照组饲喂基础日粮,试验Ⅰ组添加0.05%大蒜素和杜仲的复方中草药添加剂;试验Ⅱ组添加0.10%大蒜素和杜仲的复方中草药添加剂;试验Ⅲ组添加0.15%大蒜素和杜仲的复方中草药添加剂.每个处理设3个重复,每个重复50尾。结果表明:添加大蒜素和杜仲的复方中草药添加剂能提高细鳞鱼的最终体重、增重率,且试验Ⅱ、Ⅲ组与对照组相比,差异显著(P<0.05),试验Ⅱ、Ⅲ组之间无显著差异(P>0.05);饵料系数降低,且试验Ⅱ、Ⅲ组与对照组相比,差异显著(P<0.05),试验Ⅱ、Ⅲ组之间无显著差异(P>0.05);对存活率无显著影响。结论:饲料中添加0.10%大蒜素和杜仲的复方中草药添加剂可以有效提高细鳞鱼生长性能。     

黄芪、蒲公英和金银花复方中草药对奶牛产奶性能及血清生化指标的影响北大核心

试验旨在研究黄芪、蒲公英和金银花复方中草药对奶牛产奶性能、血清生化、抗氧化、免疫指标的影响。选取20头处于泌乳中期的中国荷斯坦奶牛,随机分为4组,每组5个重复,每个重复1头奶牛。对照组奶牛饲喂基础日粮,各试验组分别在基础日粮中添加100、200、300 g/d的中草药添加剂。预试期10 d,正式试验期21 d。结果显示,试验第1~3周,试验Ⅲ组奶牛的平均日产奶量最高,显著高于对照组(P<0.05)。试验Ⅲ组奶牛的乳脂率最高,对照组奶牛的乳脂率显著低于其他组(P<0.05)。试验Ⅲ组奶牛体细胞数最低,显著低于对照组和试验Ⅰ组(P<0.05)。对照组奶牛血清谷草转氨酶(AST)和肌酸激酶(CK)活性最高,显著高于试验Ⅱ组和试验Ⅲ组(P<0.05)。试验Ⅰ组奶牛血清免疫球蛋白G(IgG)含量最高,显著高于对照组和试验Ⅲ组(P<0.05)。研究表明,黄芪、蒲公英和金银花复方中草药添加剂能够显著提升奶牛的平均日产奶量和乳脂率,改善奶牛的肝肾功能,但对牛奶中乳蛋白和乳糖含量影响不明显,适宜添加量为200 g/d。     

日粮中添加α-硫辛酸对家兔生长性能、血清免疫、抗氧化指标及肉品质的影响

为了研究日粮中添加不同比例的α-硫辛酸对家兔生长性能、血清免疫、抗氧化指标及肉品质的影响,试验选取体重相近的35日龄家兔240只,随机分为4组,每组3个重复,每个重复20只,对照组饲喂基础日粮,试验Ⅰ组、试验Ⅱ组、试验Ⅲ组分别在基础日粮中添加200,400,600 mg/kg的α-硫辛酸,预试期5 d,正试期35 d,测定其生长指标、血清免疫与抗氧化指标及肉品质指标。结果表明：试验Ⅱ组平均日增重显著高于对照组(P<0.05);试验Ⅱ组的料重比显著低于对照组和试验Ⅰ组(P<0.05)。试验Ⅱ组的血清免疫球蛋白A(IgA)含量显著高于对照组和试验Ⅰ组(P<0.05);试验Ⅱ组、试验Ⅲ组的血清免疫球蛋白G(IgG)含量均显著高于对照组(P<0.05)。试验Ⅱ组、试验Ⅲ组的总抗氧化能力(T-AOC)显著高于对照组和试验Ⅰ组(P<0.05);试验Ⅱ组、试验Ⅲ组的谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性均显著高于对照组(P<0.05);三个试验组丙二醛(MDA)含量均显著低于对照组(P<0.05)。试验Ⅱ组、试验Ⅲ组的屠宰后24 h...     

Endocrine relationships of Meishan and White composite females after weaning and during the luteal phase of the estrous cycle

Endocrine differences between European crossbred and Chinese Meishan females have been somewhat modest. Indwelling jugular cannulas were placed in Meishan (n = 7) and White composite (n = 6) multiparous sows before weaning, and blood was sampled from 4 h before to 240 h after removal of litters. Temporal changes in FSH, triiodothyronine (T3), and tetraiodothyronine (T4) after weaning differed between Meishan and White composite sows. Plasma cortisol concentrations were higher in Meishan sows than in White composite sows (P < 0.01), but there were no temporal differences between breeds after weaning. Other hormones monitored (prolactin, GH, IGF-I, and inhibin) were not different between breeds. In the second experiment, Meishan gilts (n = 7) and sows (n = 7) and White composite sows (n = 9) were cannulated during the luteal phase of the estrous cycle and sampled after treatments consisting of GnRH (15 and 150 ng/kg BW), ovariectomy, estradiol cypionate challenge after ovariectomy (10 microg/kg BW), and GnRH antagonist. In response to GnRH challenge, White composite sows had elevated (P < 0.05) concentrations of gonadotropins compared with Meishan. Cortisol concentrations were elevated in Meishan as compared with White composite females (P < 0.01) but unaffected by GnRH treatment. After ovariectomy, LH concentrations increased 3 h sooner in White composite than in Meishan females. After GnRH antagonist, declines in gonadotropins were comparable in both breeds, but LH increased in Meishan females by 20 h but not until after 54 h in White composite females. White composite females demonstrated only a short decline in FSH in response to the GnRH antagonist, but Meishan females had a prolonged decline in FSH concentrations. Consistently elevated cortisol concentrations in Meishan females may positively impact ovarian function; thus, the assumption that high plasma cortisol concentration as an index of stress that impairs reproductive function should be reevaluated in swine. There were few endocrine differences that would relate to or explain increased ovulation rates found in the Meishan breed; thus, other mechanisms must exist to explain the increase in ovarian function in the Meishan breed.     

含不同比例梅山猪血缘杂交肉猪胴体品质研究

选不同比例梅山猪血缘 (梅山猪血缘比例为 0 ,1 / 8,1 / 4 ,3 / 8,1 / 2 ,1 )的杂交仔猪 68头 ,采用单因子试验设计 ,在同一营养水平 (DE :前期 1 4.2 1兆焦 /千克 ,后期 1 3 .79兆焦 /千克 ;CP :1 5 % ,1 3 % ;Lys:0 .75 % ,0 .65 % )下 ,研究不同梅山猪血缘比例对不同体重阶段生长肥育猪胴体品质 (平均膘厚、眼肌面积、瘦肉率等 )的影响。结果表明 :梅山猪与国外猪种杂交后 ,1 / 2梅山 ,1 / 4梅山 ,1 / 8梅山杂交猪的胴体品质显著高于 (P <0 .0 1 )纯种梅山猪。在同一体重下 (1 1 0kg) ,3 / 8梅山 ,1 / 2梅山和纯种梅山猪的平均膘厚显著高于其它血缘组 (P <0 .0 1 ) ,1 / 8梅山 ,1 / 4梅山和杜×大杂交猪间差异不显著 (P >0 .0 5 ) ;瘦肉率和眼肌面积随梅山猪血缘比例增加 ,逐渐下降 ;同一血缘不同体重阶段生长肥育猪随体重 (或饲养天数 )增加 ,平均膘厚、眼肌面积、瘦肉率呈显著二次曲线变化 (P <0 .0 1 ) ,肥育猪在适宜体重下屠宰 ,改善胴体品质     

Direct and maternal breed effects on growth and milk intake of piglets: Meishan versus Dutch breeds

Cross fostering techniques were used to evaluate pre-natal (direct genetic and maternal) and post-natal (maternal) breed effects in Meishan and Dutch breeds on milk intake and growth of piglets during the suckling period and growth after weaning. Meishan as well as Dutch sows nursed mixed litters of Meishan and Dutch piglets. Birth weight of Dutch as compared to Meishan piglets was 56% higher. The effects of this birth weight difference on milk intake and growth of piglets were studied. Data on 44 mixed litters nursed by 21 Dutch and 23 Meishan sows were available.At an average birth weight difference, growth rate from birth to 21 and 21–35 d was 25 and 31% higher for Dutch than for Meishan piglets respectively, while milk intake per piglet at days 13 and 30 of lactation was 38 and 36% higher, respectively. Differences between Dutch and Meishan sows were small.Higher growth during the suckling period of Dutch as compared to Meishan piglets was mainly caused by their higher birth weight. Results indicate that Meishan sows have good maternal characteristics, i.e. significantly lower piglet mortality and the ability to raise also the heavier, more demanding Dutch piglets.     

The impacts of uterine environment and fetal genotype on conceptus size and placental vascularity during late gestation in pigs.

Meishan and Yorkshire gilts were bred exclusively to Yorkshire and Meishan boars, respectively, resulting in similar Meishan x Yorkshire fetuses gestating in the uteri of both maternal breeds. Gilts of both breeds were slaughtered on d 90 and 110 of gestation, and the weight and volume of each uterine horn was determined. Fetal weights and crown-rump lengths were recorded. A section of the chorioallantoic-endometrial attachment site was collected for each conceptus and evaluated for placental and endometrial vascular density. An intact placenta was recovered for each conceptus and weighed, and its surface area was determined. Fetal weight and crown-rump length increased (P < .001) markedly between d 90 and 110 of gestation in Meishan and in Yorkshire uteri, but they were markedly less (P < .001) in Meishan than in Yorkshire uteri. Placental weight and placental surface area were reduced by 40% in Meishan, compared with Yorkshire, uteri; however, placental size did not increase between d 90 and 110 in either uterine type. Placental vascular density and associated endometrial vascular density were similar (P > .20) for conceptuses in Meishan and Yorkshire uteri on d 90 and 110 of gestation. Additionally, even though the ratio of fetal weight: placental weight (placental efficiency) increased between d 90 and 110, placental efficiency was similar for conceptuses in Meishan and Yorkshire uteri. In a previous study using straightbred Meishan or Yorkshire conceptuses gestated in either a Meishan or Yorkshire uterus, we found Meishan conceptuses had a markedly greater placental efficiency than did Yorkshire conceptuses, regardless of the type of uterus in which they were gestated. These data indicate that uterine type determines conceptus size and conceptus genotype controls placental efficiency.     

Age-related changes of reproductive hormones in young Meishan boars

Meishan pigs are known for their early sexual maturity. On the other hand, they grow slowly. There is no information currently available about the combination of these two characteristics in Meishan pigs. To study the developmental characteristics of Meishan pigs, the plasma concentrations of LH, FSH, inhibin, testosterone, estradiol-17beta, progesterone and insulin-like growth factor-I (IGF-I) in young Meishan boars were determined using RIA and ELISA. Inhibin decreased with age in weeks, while testosterone and estradiol-17 beta increased. Testosterone increased gradually, and an increase in estradiol-17beta occurred after sexual maturity. IGF-I increased before puberty and subsequently decreased just after puberty like a pubertal IGF-1 surge. FSH, LH and progesterone did not change with age. There was no significant correlation among the hormones. During the experimental period, the Meishan boars showed large individual differences. These differences may depend on the fact that Meishan boar reach maturity at 12 weeks of age and continue to grow thereafter.     

梅山猪与西方猪生长性能和胴体特性的比较研究

综述了梅山猪与西方猪生长性能和胴体特性的比较研究.结果表明梅山猪主要以生长性能差和脂肪组织高度发育为特性,梅山猪与西方猪相比,具有显著较低的日增重、采食量和瘦肉组织百分率以及较高的饲料转化率和背膘厚度,但梅山猪的肉质优于欧洲猪的.     

Comparisons of blood biochemical parameters,digestive enzyme activities and volatile fatty acid profile between Meishan and Yorkshire piglets

This study was conducted to compare physiological characteristics between Meishan and Yorkshire piglets in their early lives. Six healthy purebred Meishan sows and Yorkshire sows with close farrowing dates were used in this research. The piglets sucked their respective sow's milk for 14 days, then they were slaughtered to collect samples of blood, pancreas, contents of stomach, jejunum, cecum, colon as well as feces for analysis of blood biochemical parameters, digestive enzymes, and volatile fatty acid(VFA). The results showed that Yorkshire piglets had higher concentrations of high-density lipoprotein cholesterol(HDL-C) and total cholesterol(TC)(P 0.05). Gastric lipase activity was higher in Meishan piglets but Yorkshire piglets had higher lactase activity(P 0.05). The total VFA together with acetate and propionate in cecum and colon were higher in Meishan piglets than in Yorkshire piglets(P 0.05),but acetate in jejunum and ratio of acetate to propionate in colon were lower in Meishan piglets than in Yorkshire piglets(P 0.05). In conclusion, in early suckling period, significant differences exist in host metabolism and intestinal microbial metabolism between Meishan and Yorkshire piglets.     

黄烷醇对动物胰岛素抵抗状态下血糖稳态的调控作用及其机理

血糖稳态对动物机体各项生理功能的正常发挥起着重要作用。黄烷醇是一类来源于植物的生物类黄酮物质,研究表明,黄烷醇可以平衡动物胰岛素抵抗状态下的血糖稳态,其机制可能涉及调节肠道碳水化合物的消化吸收效率、增加胰高血糖素样肽-1的活性、促进胰岛β细胞分泌胰岛素、提升肝糖原合成效率以及降低机体炎症来保护胰岛素信号转导途径不被破坏等方面。本文将黄烷醇对动物胰岛素抵抗状态下血糖稳态的调控作用及其机理作一概述,为其在生产和临床上的应用提供依据。     

Cellularity of developing subcutaneous adipose tissue in Landrace and Meishan pigs: Adipocyte size differences between two breeds

Experiments were designed to compare the adipocyte cellularity of subcutaneous adipose tissue between growing Landrace (low backfat) and Meishan (high backfat) pigs at 1 week, 3 weeks, 6 weeks, 3 months and 5 months of age. As pigs aged, body weight and backfat thickness of both breeds significantly increased. When compared at equal ages, backfat thickness adjusted to equal body weight was greater for Meishan pigs. The mean diameter of fat cell size also increased with age, and by 6 weeks adipocytes from both outer and inner layers of subcutaneous adipose tissue were larger in Meishan pigs. At 5 months, approximately 80% of the adipose tissue mass in Meishan pigs was attributable to adipocytes measuring 95–165 µm in diameter, whereas adipocytes of 75–145 µm comprised most of the tissue mass in the Landrace. Although the contribution of smaller adipocytes (25–45 µm) to the tissue volume was negligible, both breeds showed a biphasic diameter distribution at all ages, suggesting that adipocyte hyperplasia is still active. Our results demonstrate that cellularity differences exist between the subcutaneous adipose tissues of Landrace and Meishan pigs, and adipocyte hypertrophy is the most overwhelming contributor to the greater backfat deposition for Meishan pigs.     

Differences in calpain system,desmin degradation and water holding capacity between commercial Meishan and Duroc × Landrace × Yorkshire crossbred pork

The objective of this study was to examine the differences in calpain system, desmin degradation, pH values and water holding capacity (WHC) between muscles of commercial Meishan and Duroc × Landrace × Yorkshire crossbred pigs. Meishan pork presented better WHC evidenced by lower purge loss at days 1 and 3 and less centrifugation loss at day 1 post mortem (P < 0.05). pH values at 45 min post mortem in Meishan pork were significantly higher compared to crossbred pork (P < 0.05). Calpain‐1 messenger RNA (mRNA) expression was lower in Meishan pork compared to that from crossbred pork (P < 0.05). Additionally, calpain‐1 activity, the ratio of calpain‐1 to calpastatin activity and desmin degradation were lower in Meishan pork compared to those from crossbred pork samples (P < 0.05). The results indicate that the calpain system including mRNA expression and activity were different between commercial Meishan and crossbred pork resulting in difference in the degree of desmin degradation during post mortem aging. pH values at 45 min and 24 h post mortem rather than calpain activity and desmin degradation could explain the higher water holding capacity in commercial Meishan pork.