Evaluation of Nutritional Value and Safety of Black Soldier Flies Fed on Dead Pig Meat and Bone Meal

[Objectives]This study was conducted to evaluate the nutritional value and safety of black soldier flies fed with dead pig meat and bone meal(DPMBM)and to explore the resource utilization of DPMBM.[Methods]The general nutrient composition,amino acids,fatty acids and mineral elements of black soldier fly meal(BSLM)were detected and analyzed.[Results]The results showed that the contents of moisture,crude protein,crude fat and ash in BSLM were 3.42%,42.31%,34.04%and 5.40%,respectively.The contents of total amino acids(TAA),essential amino acids(∑EAA)and non-essential amino acids(∑NEAA)and umami amino acids(∑DAA),the EAA/TAA value and the EAA/NEAA value were 37.93%,13.08%,24.85%,13.43%,34.47%,52.61%,respectively.A total of eight kinds of saturated fatty acids and seven kinds of unsaturated fatty acids were detected,accounting for 63.65%and 32.67%of the total fatty acids.Among the major mineral elements,the content of Ca was the highest,followed by K,Mg and Na.Among the trace mineral elements,the content of Mn was the highest,followed by Fe,Zn,Cu,Ni,Cr,Cd,As,Pb,Se,Sn,Ti,Sb and Hg.The contents of heavy metal mineral elements in BSLM were far lower than the limits specified in Hygienical Standard for Feeds.[Conclusions]In conclusion,BSLM has high nutritional value and good safety of heavy metals,and thus great potential for development and utilization as a high quality dietary protein,fat and mineral elements source.

Distribution of H-FABP mRNA in Hybrids of Songliao Black Pig×Sus scrofa

[ Objective] This study was to investigate the distribution of H-FABP mRNA in hybrids of Songliao black pig x Sus scrofa, so as to provide references for revealing the physiological functions of this gene. [Method] With the mRNA from different tissues as template, RT-PCR amplification was carried out for cloning cDNA of hybrid pig, which was then used for PCR reaction using specific primers; the amplification products were separated by gel electrophoresis and analyzed by sequencing for detecting the distribution pattern of H-FABP mRNA in hybrids of Songliao black pig x Sus scrofa. [ Result] H-FABP expressed in all the twelve tissues including subcutaneous fat, abdominal fat, mammary gland, Iongissimus dorsi muscle, dorsal deltoid muscle, heart, liver, spleen, lung, kidney, ileum and duodenum. [ Conclusion] The wide distribution of H-FABP gene suggests that its functions are important and multiple.

Effects on Growth Performance and Feed Digestibility of Hainan Black Pigs by Adding Lysine in Low Protein Diet

[Objective] The paper was to study the effects on growth performance and feed digestibility of Hainan black pigs by adding lysine in low prntein diet. [Method] A tntal of 36 Hainan black pigs with the body weight of （46.34±3.06） kg were randomly divided into three groups： con- trol group （protein level 15%, lysine level 0.83%）, experimental grnup 1 （protein level 13%, 0.83%）, and experimental group II （protein level 13%, lysine level 1.03）, each group had three replicates of four pigs. The trial lasted 35 d. [Result] The growth performance of Hainan black pig in grnup II had no significan! difference with that in contrail group （P〉0.05）. The apparent digestibility of chide protein and phosphorus of Hainan black pigs in Group II increased significantly （P〈0.05）, which were increased by 10.08% and 11.85% respectively compared to the control group; the apparent digestibility of calcium was increased, but the difference was not signifieant （P〉0.05）. [Conclusion] It will not reduce the growth performance of Hainan blaek pig when the protein level of diet is reduced by 2% and Ihe lysine level is increased to 1.03%. It is recommended that the diet can be used in the production of llainan black pig.

Changes in speciation,mobility and bioavailability of Cd,Cr and As during the transformation process of pig manure by black soldier fly larvae(Hermetia illucens)

The black soldier fly larvae(BSFL)(Hermetia illucens)are a good candidate for poultry and livestock manure treatment.The harvested insect bodies and feces can be used as animal feed and organic fertilizer.However,heavy metals have a negative impact on the transformation process of the manure by BSFL.Here we evaluated the effects of Cd,Cr and As in pig manure on the growth of BSFL,as well as the mobility and changes in speciation of the metals during the transformation process.The results showed that As significantly reduced the weight of BSFL,but Cr and Cd had no significant effects on BSFL growth.The bioaccumulation factors(BAFs)at various concentrations of Cd(2.8–3.7)were significantly higher than those of Cr(0.44–0.62)and As(0.43–0.45).The heavy metals in pig manure were mainly transferred to BSFL feces,and the distribution percentages of Cd,Cr and As in the BSFL feces were 52.6–62.0%,90.3–94.2%and 93.0–93.3%,respectively.Cd concentrations in BSFL feces were significantly lower than those in the pig manure,while there were no significant differences in the concentrations of Cr and As between BSFL feces and pig manure(except for the treatment with the addition of 150 mg Cr kg^(–1)).The metal speciation(weak acid soluble,reducible,oxidizable and residual fractions)in BSFL feces obviously changed when compared with pig manure.In BSFL feces,the reducible proportion of Cr decreased while the oxidizable proportion increased.Cd mainly existed in the weak acid soluble and reducible states in pig manure and BSFL feces.For As,the proportions of weak acid soluble and reducible states decreased in BSFL feces.After the BSFL transformation process,the bioavailable fraction of Cr decreased by 17.3–23.1%,but those of Cd and As did not change significantly,except for As in the CK group.These findings contribute to our understanding of the roles of BSFL during the biotransformation process of livestock manure as well as the safe utilization of transformed products.

Growth and Reproduction and Immune Traits of a New Intermediate Population of Enshi Black Pig

[Objectives] This study was conducted to illustrate the possible effects of heredity on the growth,reproduction and immune traits of Enshi Black pig.[Methods]The main growth,reproduction and immune traits of three populations( Goutou type,Shizitou type and an intermediate type between them) of Enshi Black pig were surveyed,and the correlations among these traits were analyzed.[Results]The health score of pregnant sows,average litter size and weight gain of piglets of intermediate type were all very significantly higher than those of Goutou and Shizitou types( P < 0.01).The percentage of lymphocytes of intermediate type was significantly higher than that of Goutou and Shizitou types( P < 0.05).The number of white blood cells( WBCs) and the number of neutrophils of intermediate type very were significantly higher than those of the other two types( P < 0.01).The percentages of CD3 + CD4 + double positive T cells( helper/inducer T lymphocytes) and CD3 + CD8 + double positive T cells( suppressor/cytotoxic T lymphocytes) and the CD4 +/CD8 + ratio( the ratio of helper T cells/suppressor T cells) of intermediate type were all significantly higher than those of the other two types.Correlation analysis showed that there was a very significant positive correlation between health score and litter size( P < 0.01,R = 0.336),a significant negative correlation between the percentage of lymphocytes and the number of neutrophils( P < 0.05,R =-0.733),and a significant correlation between the percentage of CD3 + CD8 + T cells and the number of platelets( P < 0.05,R = 0.700).[Conclusions] The intermediate type Enshi Black pig inherits the excellent traits of both Goutou type and Shizitou types,and thus has better growth,reproduction and immune traits than the other two types.

藏猪、川乡黑猪妊娠期子宫体繁殖功能相关lncRNA鉴定和功能预测

[目的]探讨长链非编码RNA(long non-coding RNA,lncRNA)在藏猪、川乡黑猪繁殖过程中的调控机理,筛选相关lncRNA。[方法]采集具有不同产仔数的藏猪和川乡黑猪妊娠期的子宫体组织作为样本,建立特异性猪子宫mRNA文库,利用Illumina PE150 HiSeq平台进行测序,测序结果经过质控、比对与拼接后,筛选出差异表达lncRNA并预测其靶基因,对靶基因进行GO功能和KEGG通路富集分析。随机选取7个差异表达lncRNAs进行实时荧光定量PCR验证。[结果]在藏猪和川乡黑猪子宫体中存在32个共同差异表达lncRNAs,共得到168个靶基因。GO功能分析显示,不同繁殖能力的样本共同差异表达lncRNA的靶基因主要富集于分子代谢、转录活性调节、细胞增殖调节、子宫体修饰、微量元素代谢等条目中;KEGG通路分析显示,共同差异表达lncRNA的靶基因主要富集在糖酵解过程、卵母细胞分裂、细胞寿命调节、Ras信号通路、RIG-Ⅰ信号通路、FoxO信号通路、HIF-1信号通路、调控稳态过程等。实时荧光定量PCR结果显示,7个差异表达lncRNAs的表达与转录组测序结果一致。[结论]本研究在藏猪和川乡黑猪子宫体中发现了32个可能通过调控潜在靶基因参与母猪妊娠过程的lncRNAs,为进一步研究lncRNA在母猪繁殖过程中的调节机制提供了参考依据。这些lncRNA可作为新的繁殖性状生物标记用于猪的育种过程中。

东极黑猪群体遗传结构分析及利用

东极黑猪是在我国东北部发现的一种新黑猪群体,试验旨在了解东极黑猪群体结构和遗传多样性,以期更好地保护和利用东极黑猪遗传资源。通过50k SNP芯片研究426头东极黑猪进行遗传多样性、亲缘关系和家系结构,同时加入20头大白猪及20头民猪数据开展主成分分析(Principal component analysis,PCA)。结果表明,东极黑猪57466个SNPs中有47389个SNPs通过质检;PCA结果显示,3个群体分别聚类,东极黑猪与另外两个猪种区分明显;东极黑猪群体中部分个体遗传关系较近,状态同源(Identity by state,IBS)遗传距离为0.0977~0.3589,平均值为0.2752;连续性纯合片段(Runs of homozygosity,ROH)分析发现该群体平均ROH为317.3 Mb,主要分布在200~300 Mb,群体平均近交系数(FROH)为0.133,说明存在近交情况。根据基因组亲缘关系和聚类分析结果,可将东极黑猪群体分为15个家系。综合分析表明,东极黑猪群体遗传多样性丰富,品种独特,但存在近交,建议引入新血统以防遗传多样性丢失。

性别对五莲黑猪胴体性能及肉品质的影响比较

选择体重100 kg左右的五莲黑猪20头屠宰(10头阉割公猪,10头母猪),研究不同性别试验猪的胴体性能和肉品质。结果表明,性别对试验猪的胴体性能、背最长肌脂肪酸含量影响不显著,对肉的L值和剪切力及蛋氨酸、亮氨酸、酪氨酸、赖氨酸、鲜味氨基酸含量、鲜味氨基酸占总氨基酸比例影响显著。其中,与阉公猪组相比,母猪组肉的L值极显著提高9.97%(P<0.01),剪切力极显著降低31.05%(P<0.01),蛋氨酸和酪氨酸分别提高61.29%(P<0.05)、18.95%(P<0.01);亮氨酸、赖氨酸、鲜味氨基酸含量、鲜味氨基酸占总氨基酸比例阉公猪组分别比母猪组显著提高11.88%(P<0.05)、80.73%(P<0.05)、11.16%(P<0.05)、7.38%(P<0.05)。说明性别对五莲黑猪肉的部分氨基酸含量影响显著,对猪肉的品质有一定影响。

Developmental Changes of Col3a1 mRNA Expression in Muscle and Their Association with Intramuscular Collagen in Pigs

Eighty-four castrated boars including Laiwu Black （LW） （weight 30-90 kg, n = 6） and Lulai Black （LL） （weight 40-100 kg, n = 6） were used to study the developmental changes of collagen type Ⅲ alpha 1 （Col3al） mRNA expression in the muscle and their association with intramuscular collagen （IMC）. The muscle total RNA was extracted to determine the abundance of Col3al mRNA using relative quantitative RT-PCR with β-actin mRNA as the internal standard. The results indicated that the developmental patterns of muscle Col3al mRNA in LW and LL pigs were similar. The abundance of Col3al mRNA increased with body weight, but decreased a little at 70 kg and 80 kg phases for LW and LL, respectively. On the whole, the expression level of Col3al mRNA in muscle of LW was higher than that of LL （P 〈 0.05）. Correlation analysis showed that the expression of Col3al mRNA in muscle was positively correlated with total and insoluble IMC, but was negatively correlated with IMC solubility for LW pigs （P 〈 0.01） and LL pigs （P 〈 0.05）, respectively. These results suggest that the muscle Col3al gene expression is affected by body weight and genotype and has important effect on IMC content and characteristics.

黟县黑猪微卫星遗传多样性分析

选择55头黟县黑猪的血液样品,采用PCR(聚合酶链式反应)和PAGE(聚丙烯酰胺凝胶电泳)法对14个微卫星标记进行分型,分析黟县黑猪群体的遗传多样性。结果表明:在黟县黑猪群体中,14个微卫星位点共检测出171个等位基因,平均每个位点约12个,有效等位基因数为3.11-12.37,观测杂合度范围为0.31-1;14个微卫星位点多态性含量为0.65-0.91,均具有高度多态性,累积排除概率达99.9%,说明选择的14个微卫星标记能够对黟县黑猪的亲缘关系进行鉴定。

基于SNP芯片分析徽县青泥黑猪遗传多样性和遗传结构

旨在分析徽县青泥黑猪遗传多样性和遗传结构,为其作为新遗传资源申报、保护与利用提供参考。本研究以甘肃省2个已知地方猪种(八眉猪、合作猪各20头)和待鉴定新猪种(徽县青泥黑猪28头)共68头猪为研究对象,利用“中芯一号”50K SNP芯片检测全基因组范围内单核苷酸多态性(single nucleotide polymorphisms, SNPs),采用多种软件分析徽县青泥黑猪遗传多样性、遗传结构、群体分化指数及亲缘关系。结果显示:共检测到55 156个SNPs,质控后剩余49 279个SNPs;徽县青泥黑猪的有效群体含量(N_(e))、期望杂合度(H_(e))、观察杂合度(H_(o))、多态标记比例(PN)和核苷酸多样性(Pi)分别为2.2、0.370 7、0.386 4、0.915 7、0.378 6,均高于合作猪和八眉猪,且徽县青泥黑猪的连锁不平衡系数较低,衰减速度较快;PCA显示,3个群体分别聚类,根据PC1(PC1>0)可将HX群体和HZ、BM群体区分开,进化树分析发现徽县青泥黑猪独自聚为一支,八眉猪和合作猪聚为另一大支,随后逐渐分离,群体结构显示,当K=3时,徽县青泥黑猪呈现出与八眉猪、合作猪不同的进化路线,但徽县青泥黑猪血缘较为混杂;徽县青泥黑猪与八眉猪、合作猪之间的群体分化指数分别为0.123 6和0.159 8,表明各猪种之间存在一定程度的遗传分化;IBS矩阵和G矩阵分析发现,徽县青泥黑猪大部分个体之间亲缘关系较远,少数个体亲缘关系较近。本研究基于“中芯一号”50K SNP芯片数据分析了徽县青泥黑猪的遗传多样性及遗传结构,发现徽县青泥黑猪遗传多样性高于八眉猪和合作猪,独立聚类,且与八眉猪、合作猪之间有明显的遗传分化,初步认为是甘肃地方新猪种,徽县青泥黑猪部分个体之间存在近交风险,需要加强保种,该研究为深入挖掘徽县青泥黑猪新遗传资源及合理保种利用提供参考。

北京黑猪全基因组ROH检测和选择信号分析

旨在基于长纯合片段(ROH)和选择信号iHS分析北京黑猪群体的遗传结构,挖掘与经济性状相关的候选基因。本研究的对象为北京黑猪群体,平均日龄为210 d。对729头北京黑猪的illumina Porcine 50K芯片数据进行质控和填充后,进行ROH和iHS的分析。本研究选择参与组成ROHs的前1%的SNPs作为ROH岛的阈值,将超过此阈值的区域称为ROH岛。保留标准化的iHS值中排在前1%的所有SNPs位点,将位点上下游各延伸200 kb作为选择信号iHS得到的强受选择区域。将选择信号的强受选择区域与ROH岛重叠的区段定为本研究的候选区域。本研究最终保留724个体和45585个SNPs,通过ROH分析共识别到10个ROH岛,这些岛内包含449个SNPs。iHS分析的结果显示,保留得分排在前1%的位点后,共有376个强受选择位点。最终,在iHS的强受选择区域与ROH岛的5个重叠区域内注释到18个基因,其中包括一些已知的影响猪肉质和生长发育过程的基因。本研究分析了北京黑猪群体ROH的分布,并结合选择信号,揭示了北京黑猪受选择的位点和候选基因,该研究结果为深入探讨北京黑猪的群体特性及经济性状的遗传机制提供重要参考。

紫马铃薯皮粉对黑水虻幼虫生长性能、废弃物消减率、虫体营养组分及肠道微生物的影响

本试验旨在研究育成猪粪中添加紫马铃薯皮粉对黑水虻幼虫生长性能、废弃物消减率、虫体营养组分及肠道微生物的影响。选取4日龄黑水虻幼虫3 000只,随机分为5组,每组3个重复,每个重复200只。对照组饲喂育成猪粪,试验组分别饲喂育成猪粪+2%紫马铃薯皮粉(2%添加组)、育成猪粪+4%紫马铃薯皮粉(4%添加组)、育成猪粪+6%紫马铃薯皮粉(6%添加组)和育成猪粪+8%紫马铃薯皮粉(8%添加组)。试验期16 d。结果表明:1)6%、8%添加组的幼虫平均干重显著低于对照组及2%、4%添加组(P<0.05)。各组之间废弃物消减率无显著差异(P>0.05)。2)4%、6%和8%添加组的粗蛋白质含量显著高于对照组(P<0.05),2%、4%、6%和8%添加组的粗脂肪含量显著低于对照组(P<0.05)。3)4%添加组的变形菌门相对丰度显著低于对照组(P<0.05),放线菌门、拟杆菌门、蓝菌门、疣微菌门、酸杆菌门相对丰度显著高于对照组(P<0.05)。4)4%添加组的普罗威登斯菌属、Breznakia和肠球菌属相相对丰度显著低于对照组(P<0.05),狭窄梭菌属、土孢杆菌属、棒状杆菌属、罗姆布茨菌属和苏黎世杆菌属相对丰度显著高于对照组(P<0.05)。5)狭窄梭菌属和土孢杆菌属相对丰度分别与幼虫平均干重、粗蛋白质含量呈显著正相关(P<0.05),而肠球菌属相对丰度与粗蛋白质含量呈显著负相关(P<0.05)。6)4%添加组的肠道微生物网络图连接数为3 138个,节点数为178个,高于其他各组,说明4%马铃薯皮粉添加比例下肠道最为复杂。由此可见,育成猪粪中添加4%紫马铃薯皮粉能在不影响幼虫平均干重和废弃物消减率情况下,提高虫体粗蛋白质含量,降低粗脂肪含量,有益于幼虫肠道健康,有利于提升昆虫蛋白质生产效率。

北京黑猪AQP9和RPS10基因多态性及其与背膘厚的关联分析

旨在研究水通道蛋白9(aquaporins9,AQP9)及核糖体蛋白10(ribosomal protein S10,RPS10)基因多态性及其与北京黑猪背膘厚的相关性,以期能够获得北京黑猪背膘厚的有效标记。本研究以413头北京黑猪为研究对象,测定不同部位(肩部、6-7肋间、胸腰结合、腰荐结合)的背膘厚度。PCR扩增AQP9和RPS10基因的启动子区和外显子区序列筛选SNP位点,并将SNPs与各部位背膘厚进行关联分析。运用荧光定量PCR检测基因的差异表达。结果发现,AQP9基因启动子区有4个突变位点,其中1个SNP:rs332699245 A>C与胸腰结合处背膘厚关联显著(P<0.05),且该位点突变预测到了结合转录因子的改变;RPS10基因在3′UTR、CDS区共有8个突变位点,其中5个与背膘厚显著关联:rs80795904 C>G、rs80932213 T>C与6~7肋间背膘厚关联显著(P<0.05),rs3469834461 C>T与肩部背膘厚、四点平均背膘厚关联显著(P<0.05),rs80862457 C>T与胸腰结合处背膘厚、腰荐结合处背膘厚关联显著(P<0.05),rs336938272 A>C与6~7肋间背膘厚、腰荐结合处背膘厚、四点平均背膘厚均关联显著(P<0.05);且在3′UTR区检测到1个SNP(rs80862457 C>T),位于小RNA(microRNA,miRNA)结合靶点。基因表达差异分析表明,rs332699245 A>C中AA型个体的AQP9基因mRNA水平显著高于AC型个体(P<0.05),rs80862457 C>T中TT型个体的RPS10基因mRNA水平显著高于CC型个体(P<0.05)。综上所述,AQP9和RPS10基因与北京黑猪背膘厚显著关联,rs332699245 A>C和rs80862457 C>T位点可作为北京黑猪背膘厚选育的潜在分子标记,为北京黑猪的选育提供理论支撑。

江泉黑猪GPAT 3基因多态性及其与生长性状的关联分析

【目的】探究江泉黑猪甘油-3-磷酸酰基转移酶3(glycerol-3-phosphate acyltransferase 3,GPAT3)基因多态性及其与生长性状的相关性,为江泉黑猪的遗传改良和优化繁殖计划提供理论和技术支持。【方法】采集292头江泉黑猪的耳组织样并提取DNA,PCR扩增GPAT 3基因片段,结合Sanger测序与MassARRAY核酸质谱分析系统检测单核苷酸多态性(single nucleotide polymorphism,SNP)位点及基因分型。利用R语言3.6.2、HaploView、PHASE等软件进行GPAT 3基因SNP位点的遗传效应、连锁不平衡和单倍型分析。利用SAS 9.2软件分析GPAT 3基因SNP位点及其构成的单倍型块与江泉黑猪生长性状的相关性。【结果】在GPAT 3基因及其5′-调控区共发现10个SNPs,其中4个为低度多态,6个为中度多态;7个SNPs位点基因型频率分布处于哈代-温伯格平衡状态。关联分析发现,9个SNPs与江泉黑猪生长性状呈显著关联(P<0.05),其中g.134957929 G>A、g.134957930 G>T、g.134958013 G>A和g.134976983 T>C存在极强连锁,构建的AGGT/AGGT双倍型在胸围、体高方面具有显著优势(P<0.05),GTGC/GTGC双倍型和GTGC单倍型在体长方面具有显著优势(P<0.05);g.135002556 C>A、g.135002627 C>T、g.135002680 C>T存在极强连锁,构建的ATC/ATC双倍型在胸围、腹围方面具有显著优势(P<0.05),CCC/ATC双倍型在背膘厚方面具有显著优势(P<0.05),ATT单倍型在腹围方面具有显著优势(P<0.05)。【结论】江泉黑猪GPAT 3基因具有丰富的多态性位点,9个SNPs及其构成的2个单倍型块与江泉黑猪胸围、腹围、体高等有显著关联性,可作为江泉黑猪生长性状选育的分子遗传标记。

甘肃4种地方杂交黑猪肉品质与营养成分比较

试验旨在分析比较4种杂交黑猪肉的肉质性状、营养成分、氨基酸和脂肪酸等含量的差异,为地方特色杂交黑猪肉生产提供数据支撑和理论依据。试验选择甘肃省舟曲县4个农民合作社提供的4个品种杂交黑猪24头,采集每头猪背最长肌,采用国标法测定肉质和常规营养成分指标。结果表明:中舟黑猪失水率、熟肉率显著高于其他三种黑猪(P<0.05)。中舟黑猪肌肉中粗脂肪含量显著高于其他三种黑猪(P<0.05),粗蛋白含量显著高于河太黑和杜太黑猪(P<0.05)。中舟黑猪肌肉中饱和脂肪酸和单不饱和脂肪酸含量显著高于其他三种黑猪(P<0.05),不饱和脂肪酸和多不饱和脂肪酸显著低于其他三种黑猪(P<0.05);中舟黑猪肌肉中氨基酸总量显著低于杜关黑猪和杜太黑猪(P<0.05),但肌肉中鲜味氨基酸含量高于其他三种黑猪。说明中舟黑猪肌肉中氨基酸更丰富,脂肪酸比例更合理,更适合进行保种和开发研究。

北京黑猪脂肪前体细胞的分离培养及成脂诱导分化研究

旨在建立北京黑猪脂肪前体细胞的分离培养及成脂诱导分化培养体系,为研究猪脂肪沉积的分子机制提供试验材料,为生物培育肉的制备提供技术指导。本研究采集1头7日龄健康的北京黑猪公猪的颈部皮下脂肪组织,使用机械法联合I型胶原酶消化法分离脂肪前体细胞。对获得的脂肪前体细胞进行形态观察、生长曲线绘制、免疫荧光鉴定、成脂诱导分化、油红O染色、BODIPY染色、甘油三酯含量测定及使用实时荧光定量PCR和Western blot技术检测成脂分化相关基因的表达。结果表明,分离的北京黑猪脂肪前体细胞贴壁后呈长梭形,细胞生长曲线呈S型。免疫荧光结果表明,PREF1表达为阳性,表明分离的细胞的确为脂肪前体细胞。在相同的诱导试剂组合条件下,使用10%FBS比2%FBS成脂诱导分化效果更好。在相同血清浓度的情况下,鸡尾酒法与油酸钠、罗格列酮共同联用的细胞分化效果较好。分化8 d的细胞中出现大量的脂滴,脂滴经油红O染色呈红色,经BODIPY染色呈绿色。且分化8 d的细胞中甘油三酯的含量显著升高(P<0.001)。qPCR结果显示,PPARγ、CEBPα、ACCα、LPL、SCD和FABP4在分化2 d时表达量均显著升高(P<0.05),4~6 d达到高峰,8 d时表达量降低。Western blot结果表明,PPARγ、CEBPα、FABP4、APN在细胞分化过程中表达逐渐上调。PREF1在细胞分化过程中表达逐渐下调。在三维培养情况下,使用10%FBS,鸡尾酒法与油酸钠、罗格列酮共同联用也能使脂肪前体细胞分化为成熟的脂肪细胞,分化8 d的细胞中脂滴经BODIPY和油红O染色后分别呈绿色和红色,且PPARγ、CEBPα、ACCα、LPL、SCD和FABP4在分化8 d的细胞中的表达量显著上调(P<0.001)。综上所述,本研究成功建立了北京黑猪脂肪前体细胞的分离与培养体系,并筛选出适合二维和三维培养的成脂诱导分化方法,为进一步研究猪脂肪沉积的分子机制和改善肉品质奠定基础,也为细胞培育肉的制备提供技术指导。

苏农黑猪生长特征和采食行为分析及其性别差异比较

旨在研究新培育品种苏农黑猪的生长发育规律。选取体重35 kg左右、日龄102 d左右的苏农黑猪阉公猪和母猪各30头,将同性别的猪按体重随机分入3个栏,每栏10头,当苏农黑猪饲喂至体重110 kg左右结束试验。通过种猪生产性能测定站获取生长性能与采食相关指标数据,研究其生长发育规律及性别差异,并使用多种函数拟合生长曲线及消化能、粗蛋白摄入与体重的曲线。结果:阉公猪生长至110 kg所需的平均天数显著低于母猪(P<0.05),平均日增重和平均日采食量极显著高于母猪(P<0.01),平均日采食时间极显著高于母猪(P<0.01)。生长曲线的拟合结果以von Bertalanffy模型为最优,阉公猪和母猪的拐点日龄、拐点体重和最大日增重分别为126 d、50.931 kg、0.764 kg和111 d、41.791 kg、0.752 kg。消化能、粗蛋白摄入与体重曲线的拟合结果以ExpDec1模型为最优,拟合得到的预测值均高于猪营养需要量中的推荐值。相较于母猪,阉公猪营养需要量预测值更高。综上,苏农黑猪阉公猪生长性能优于母猪,von Bertalanffy模型能较好地预测苏农黑猪生长发育情况,ExpDec1模型能较好地预测苏农黑猪能量和蛋白摄入量。

大河乌猪火腿中新型α-葡萄糖苷酶抑制肽的分离、鉴定及活性研究

大河乌猪火腿在发酵和后熟过程中蛋白质降解可产生丰富的生物活性肽。为探究大河乌猪火腿中是否存在α-葡萄糖苷酶抑制肽及其活性,以大河乌猪火腿为研究对象,通过超滤分离方法制备了不同分子质量的火腿肽;以α-葡萄糖苷酶抑制率为指标,采用肽组学结合生物信息学分析方法对火腿肽进行鉴定、筛选和活性研究。结果表明:分子质量小于3 kDa的大河乌猪火腿肽具有良好的α-葡萄糖苷酶抑制活性。从大河乌猪火腿中共鉴定出143条主要来源于肌球蛋白、肌钙蛋白和β-烯醇化酶的肽序列,进一步筛选出的肽段IEEALGDK具有良好的α-葡萄糖苷酶抑制活性(IC_(50)值为1.42 mg/mL)。BIOPE P-UWM数据库检索结果显示,肽段IEEALGDK为新型的生物活性肽。肽的稳定性研究表明,肽段IEEALGDK具有较好的热稳定性、耐酸碱性和胃肠道消化稳定性。分子对接结果显示,肽段IEEALGDK主要通过氢键和疏水相互作用占据α-葡萄糖苷酶的活性残基位点Arg594、Arg727、Arg799和Arg467发挥活性作用。大河乌猪火腿的肽段IEEALGDK为新型生物活性肽,具有良好的α-葡萄糖苷酶抑制活性,研究旨在为大河乌猪火腿肽的进一步开发和利用提供理论参考。

复合蛋白源替代鱼粉对凡纳滨对虾生长性能、饲料利用和免疫性能的影响

试验旨在研究饲料中使用复合蛋白源(猪血球蛋白粉、玉米蛋白粉和酶解脱脂黑水虻粉)替代鱼粉对凡纳滨对虾生长性能、饲料利用、免疫性能和耐氨性的影响。挑选初重(1.01±0.01)g健康有活力的凡纳滨对虾1440尾,随机分为6组,每组4个重复,每个重复60尾凡纳滨对虾。复合蛋白源分别等氮、等脂替代0、20%、40%、60%、80%和100%的鱼粉,分别命名为M1组、M2组、M3组、M4组、M5组和M6组。试验期56 d。结果显示,M4组凡纳滨对虾的增重率和特定生长率显著高于M1组(P<0.05)。M2组、M3组和M4组凡纳滨对虾的饲料效率显著高于M1组(P<0.05)。M6组凡纳滨对虾血清中谷草转氨酶(AST)、谷丙转氨酶(ALT)活性和总胆固醇(CHO)、甘油三酯(TG)含量显著高于M1组(P<0.05),血清中碱性磷酸酶(AKP)活性和总蛋白(TP)含量显著低于M1组(P<0.05)。M6组凡纳滨对虾肝胰腺谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)和酸性磷酸酶(ACP)的活性显著低于其他各组(P<0.05),丙二醛(MDA)含量显著高于M1组、M2组和M3组(P<0.05)。氨氮胁迫18 h后,M6组凡纳滨对虾存活率显著低于其他各组(P<0.05)。研究表明,饲料中复合蛋白源替代鱼粉比例为60%时,可以改善凡纳滨对虾的生长性能,复合蛋白源替代鱼粉比例过高(超过80%)会降低凡纳滨对虾的饲料利用率、免疫力及抗应激能力。