Understanding the metabolic profile of backfat is essential for optimizing breeding strategies and improving pork production. While the early stages of adipose tissue development have been partially characterized, metabolic alterations during the fattening phase (180-360 days)- a critical period for physiological maturation and carcass trait formation-remain insufficiently understood. In this study, we characterized the metabolomic profiles of backfat from Ningxiang pigs across four developmental stages (180d, 240d, 300d, 360d) and evaluated their relationships with carcass traits. A total of 154 metabolites exhibited significant temporal variation (q < 0.05), including functional lipids such as methanandamide phosphate and oleoylethanolamide, which are associated with appetite regulation and lipid metabolism. The progressive accumulation of bioactive exogenous metabolites like α-tocotrienol and cephaeline, indicated potential stage-dependent immunometabolic adaptations. In contrast, several synthetic xenobiotics, potentially derived from feed additives or environmental exposure, accumulated in backfat tissue and may represent potential risks to animal health and pork safety. Co-expression network analysis identified a metabolite module strongly associated (|R| > 0.7, q < 0.05) with key carcass traits, within which psychotrine-an understudied plant-derived alkaloid not previously associated with animal growth- was identified as a hub metabolite. This study establishes a comprehensive metabolic characterization of backfat during the fattening phase in an indigenous pig breed. Collectively, these findings provide novel candidate biomarkers for carcass trait prediction, highlight the potential impact of synthetic compound accumulation, and offer valuable insights for precision breeding, nutritional management, and meat safety assessment in swine production.

Indigenous pigs constitute crucial genetic reservoirs. Adipose tissue is central to pig growth and metabolism, yet its molecular ontogeny remains poorly characterized in indigenous breeds such as the Ningxiang pig. We employed mass spectrometry to profile backfat proteomes across six postnatal stages (60-360 days). Proteomes clearly separated early (60-120 days) from late stages (300-360 days). Older pigs showed enrichment in processes linked to energy metabolism, translation, immune function, and mitochondrial activity. We identified 43 lipid metabolism proteins exhibiting significant age-dependent abundance. Weighted co-abundance network analysis revealed four protein modules significantly correlated with lean meat percentage, fat percentage, and carcass weight. Intramodular analysis identified four hub proteins-ALDH18A1, FABP4, FBP1, and HADHB-as putative candidates associated with lipid transport, gluconeogenesis, and fatty acid oxidation. This study links temporal proteomic profiles with key carcass traits, providing a data resource and a network-based framework for future research.

Indigenous pig breeds in China possess distinct biological characteristics, yet their growth dynamics and feeding behaviors remain inadequately characterized. This study compared growth performance, feed conversion ratio (FCR), and feeding behavior in four Hunan indigenous pig breeds, Dongshan (DS), Longtan (LT), Pushi (PS), and Taoyuan (TY), during the fattening stage (approximately 50–90 kg, over 60 days). Automated feeding stations were used to continuously monitor body weight, feed intake, and feeding behavior over 60 days in 48 pigs (12 per breed). Linear mixed model and generalized additive mixed model (GAMM) were employed to analyze growth trajectories, FCR dynamics, and temporal feeding patterns. The PS breed exhibited the highest daily gain (0.785 kg/day) and lowest FCR (3.98), whereas the DS breed showed the poorest feed efficiency (FCR 4.83). GAMM revealed significant non-linear changes in FCR and feeding rate across growth stages, with breed-specific critical windows of divergence. Notably, the TY breed achieved comparable growth to DS and LT with superior feed efficiency, suggesting adaptive metabolic characteristics. Diurnal feeding rhythms were conserved across breeds, despite marked differences in absolute feeding rates. These findings provide a fundamental database for precision feeding management and genetic improvement of indigenous pig breeds.

Feed is the largest cost in pig production, driving interest in alternative ingredients that maintain performance at lower expense. Alfalfa, a nutrient-rich and widely available forage legume, shows promise as a partial feed substitute. However, it remains unclear how partial replacement with alfalfa affects growth dynamics, feed efficiency, and feeding behavior across fattening stages in pigs. This study investigated the effects of substitution with 8% alfalfa or alfalfa silage on growth performance and feeding behavior in growing-finishing pigs over a 60-day fattening period (60-130 kg). A total of 24 pigs were randomly assigned to three diet treatments: commercial feed, 8% alfalfa substitution, or 8% alfalfa silage substitution. Weight, feed intake, feed conversion ratio (FCR), and feeding hour were measured and analyzed using linear mixed-effects models and generalized additive mixed models. Results showed no significant effects of alfalfa on overall weight, feed intake or FCR. However, Pigs fed commercial feed showed superior FCR during mid-fattening (weeks 2.8-5.2, P < 0.05) but worse FCR than alfalfa-fed groups during late-finishing phase (weeks 6.6-8, P < 0.05). Moreover, alfalfa silage altered animal behavior by shifting feeding hour by roughly three hours earlier (P < 0.05). In summary, substitution with 8% alfalfa or alfalfa silage can be incorporated without compromising overall pig performance. While, integrating alfalfa in later fattening stages could further improve feed efficiency and reduce costs. This supports the use of phase-specific feeding strategies and adoption of such practices could enhance both economic and environmental sustainability in commercial pig farming.

Lipids and volatile organic compounds (VOCs) are essential contributors to meat flavor. However, no studies to date have comprehensively explored the lipids and VOCs in raw pork from Ningxiang (NX) pigs and their hybrid breed Berkshire × Ningxiang (BN) pigs. This study aimed to identify the lipids and VOCs and reveal the crucial lipids for characteristic flavor formation. Samples were collected from the longissimus dorsi muscle of six NX and BN 8-month-old pigs each. The intramuscular fat (IMF) content of NX pork was 5.43%, almost twice that of BN pork (p < .01). Total 187 significantly different lipids were identified between NX and BN pork (variable importance in projection scores > 1, p < .05). Further analysis suggested 38 lipids were potential markers. Out of 66 identified VOCs, 16 key VOCs were screened both in NX and BN pork. Furtherly, hexanal-D, 2-methylbutanal, 3-methylbutanal, 1-penten-3-one, 1-octen-3-ol, and ethyl acetate-D were found to be key differential VOCs. Comparing with NX pork, BN pork significantly improved pungent odor. Correlation between the lipid markers and key VOCs demonstrated that phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylinositol (PI), phosphatidylcholine (PC), and triglyceride (TG) were identified as key differentiating compounds for characteristic flavor. Our findings provided a novel understanding of pork identification and a basis for improving the flavor quality of NX and BN pork.

异位发酵床技术是一种高效处理养殖粪污的经济实用技术,畜禽粪污通过异位发酵床微生物高效处理后,可作为有机肥原料,实现资源化利用.文章总结了永州市零陵区刘文猪场的异位发酵床处理方式及利用实践经验,为畜禽粪污全量收集处理还田提供参考.

OBJECTIVE:Daweizi (DWZ) is a famous indigenous pig breed in China and characterized by tender meat and high fat percentage. However, the expression profiles and functions of transcripts in DWZ pigs is still in infancy. The object of this study was to depict the transcript profiles in DWZ pigs and screen the potential pathway influence adipogenesis and fat deposition.METHODS:Histological analysis of backfat tissue was firstly performed between DWZ and lean-type Yorkshire pigs, and then RNA sequencing technology was utilized to explore miRNAs, lncRNAs and mRNAs profiles in backfat tissue. 18 differentially expressed (DE) transcripts were randomly selected for quantitative real-time polymerase chain reaction (QPCR) to validate the reliability of the sequencing results. Finally, gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis were conducted to investigate the potential pathways influence adipocyte differentiation, adipogenesis and lipid metabolism, and a schematic model was further proposed.RESULTS:A total of 1,625 differentially expressed transcripts were identified in DWZ pigs, including 27 upregulated and 45 downregulated miRNAs, 64 upregulated and 119 downregulated lncRNA, 814 upregulated and 556 downregulated mRNAs. QPCR analysis exhibited strong consistency with the sequencing data. GO and KEGG analysis elucidated that the differentially expressed transcripts were mainly associated with cell growth and death, signal transduction, peroxisome proliferator-activated receptors (PPAR), AMP-activated protein kinase (AMPK), PI3K-Akt, adipocytokine and foxo signaling pathways, all of which are strongly involved in cell development, lipid metabolism and adipogenesis. Further analysis indicated that the BGIR9823_87926/miR-194a-5p/AQP7 network may be effective in the process of adipocyte differentiation or adipogenesis.CONCLUSION:Our study provides comprehensive insights into the regulatory network of backfat deposition and lipid metabolism in pigs from the point of view of miRNAs, lncRNAs and mRNAs.

Fat deposition is an economically important trait in pigs. Ningxiang pig, one of the four famous indigenous breeds in China, is characterized by high fat content. The underlying gene expression pattern in different developmental periods of backfat tissue remains unclear, and the purpose of this investigation is to explore the potential molecular regulators of backfat tissue development in Ningxiang pigs. Backfat tissue (three samples for each stage) was initially collected from different developmental stages (60, 120, 180, 240, 300, and 360 days after birth), and histological analysis and RNA sequencing (RNA-seq) were then conducted. Fragments per kilobase of transcript per million (FPKM) method was used to qualify gene expressions, and differentially expressed genes (DEGs) were identified. Furthermore, strongly co-expressed genes in modules, which were named by color, were clustered by Weighted gene co-expression network analysis (WGCNA) based on dynamic tree cutting algorithm. Gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) enrichment were subsequently implemented, and hub genes were described in each module. Finally, QPCR analysis was employed to validate RNA-seq data. The results showed that adipocyte area increased and adipocyte number decreased with development of backfat tissue. A total of 1,024 DEGs were identified in five comparison groups (120 days vs. 60 days, 180 days vs. 120 days, 240 days vs. 180 days, 300 days vs. 240 days, and 360 days vs. 300 days). The turquoise, red, pink, paleturquoise, darkorange, and darkgreen module had the highest correlation coefficient with 60, 120, 180, 240, 300, and 360 days developmental stage, while the tan, black and turquoise module had strong relationship with backfat thickness, adipocyte area, and adipocyte number, respectively. Thirteen hub genes (ACSL1, ACOX1, FN1, DCN, CHST13, COL1A1, COL1A2, COL6A3, COL5A1, COL14A1, OAZ3, DNM1, and SELP) were recognized. ACSL1 and ACOX1 might perform function in the early developmental stage of backfat tissue (60 days), and FN1, DCN, COL1A1, COL1A2, COL5A1, COL6A3, and COL14A1 have unignorable position in backfat tissue around 120 days developmental stage. Besides, hub genes SELP and DNM1 in modules significantly associated with backfat thickness and adipocyte area might be involved in the process of backfat tissue development. These findings contribute to understand the integrated mechanism underlying backfat tissue development and promote the progress of genetic improvement in Ningxiang pigs.

This study evaluated the effects of flavonoids from mulberry leaves (FML) on plasma biochemical indices, serum activities of lipid metabolism-related enzymes, fat morphology, fatty acid composition, and lipid metabolism in different adipose tissues of finishing pigs. We used 120 Chinese hybrid barrows of Berkshire and Bama mini-pigs with an average initial body weight of 45.11 ± 4.23 kg. The pigs were randomly assigned to five treatment groups and fed a control diet based on corn, soybean meal, and wheat bran or a control diet supplemented with 0.02%, 0.04%, 0.08%, or 0.16% FML. Each experimental group had six replicates (pens), with four pigs per pen. After a 7-d adaptation period, the feeding trial was conducted for 58 d. Blood and adipose tissue samples were collected from 30 pigs (one pig per pen) at the end of the test. The results showed that FML supplementation significantly decreased the feed intake to body gain ratio, the plasma concentrations of total cholesterol and free fatty acids, and the serum activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase (linear or quadratic effects, P < 0.05), and decreased the plasma triglyceride concentration (quadratic, P = 0.07). Increasing FML supplementation increased the average daily gain and serum activities of lipoprotein lipase (linear and quadratic effects, P < 0.05) and adipose triglyceride lipase (linear, P < 0.05). Dietary FML supplementation decreased the adipocyte area in the dorsal subcutaneous adipose (DSA) tissue of finishing pigs (linear, P = 0.05) and increased the adipocyte area in the visceral adipose tissue (quadratic, P < 0.01). Increasing FML supplementation decreased the C20:1 content in DSA, abdominal subcutaneous adipose, and visceral adipose tissues of finishing pigs (P < 0.05) and increased the C18:3n3 and n-3 PUFA contents (P < 0.05). The lipid metabolism genes were regulated by the PPARγ-LXRα-ABCA1 signaling pathway, and their expressions differed in different adipose tissues. These findings suggest that FML improved growth performance, regulated lipid metabolism, inhibited fat production, and improved fatty acid distribution in the adipose tissue of finishing pigs, thereby improving pig fat’s nutritional quality and health value.

1 引言 宁乡猪是我国四大名猪种之一,是典型的脂肪型猪种.随着近年来饲养环境及消费市场的变化,因脂肪型出名的宁乡猪逐渐被养殖户淘汰,逐渐造成了我国优质地方资源猪种饲养占有率的下降.因此,如何提高宁乡猪的瘦肉率和市场占有率逐渐成为研究者关注的问题.本试验通过对不同屠宰月龄下宁乡猪及其杂交猪内脏组织变化进行研究,以期为宁乡猪的生理特性和育种选育研究提供形态学数据资料,也为宁乡猪的开发利用提供科学依据和思路.

文章在提出原生态保种概念基础上开展了宁乡花猪保种群世代Ⅰ公猪85头、母猪464头和世代Ⅱ公猪76头、母猪428头1～16胎次不等的世代繁育,历时10年获得系统调查数据.运用该数据分析所建立的以世代界定车轮、以系谱血缘实施组配选配、以逐一轮次规范有序繁殖的原生态保种体系方法的实践效果.结果表明:1)保种群161头公猪、892头母猪闭锁繁殖4536窝41269头仔猪比《湖南省家畜家禽品种志和品种图谱》(1984版)中的宁乡花猪毛色比率趋势体现出更为发展、而与保护区种群趋势基本一致;2)产仔数、产活仔数分别为10.42头和9.10头,其最高值为20头和17头.而以标准差衡量世代间、血缘间产仔数、产活仔数均值的离散、变异,其范围为1.94～2.84头和2.02～2.78头,反映出种群内、系别间均存在高产基因及基因型个体;3)相比《湖南省家畜家禽品种志和品种图谱》(1984版)中的宁乡花猪的数据,该项原生态保种所获性能指标不仅稳定、而且有所提高.由此,体现出原生态保种概念及其体系方法的正确性和可行性.

杜洛克猪原产于美国东部,其基于市场需要,由大个体脂肪型猪品种转变为瘦肉型猪.育种形成了高瘦肉率和饲料转化率、强适应性和生长发育快的特点,因繁殖能力不出众,常作为猪育种的终端父本,现已成为世界著名的瘦肉型猪种之一.我国是集生猪养殖、消费和育种为一体的大国,不仅具有品种丰富的地方猪种,还引进了多种国际上大受欢迎的国外品种.在人们饮食习惯和生猪市场消费需求的推动下,瘦肉率和饲料转化率等较低的地方猪种退出大众市场,国内生猪养殖公司纷纷引进杜洛克等国外瘦肉型猪种进行遗传育种改良,将培育瘦肉率高、生长速度快、饲料转化率高、繁殖性能良好,同时兼顾肉品质的优质猪新品种作为猪育种领域的主要科研攻关方向.面对引种后种猪性能退化问题,国内部分生猪养殖公司基于短期盈利目标,严重依赖国外育种体系,造成被国外育种公司"牵着鼻子走"的局面.在当前形势下,充分利用国内的种猪资源,结合地区环境进行猪品种创新,选育出优良瘦肉型猪新品系尤为重要.

杜仲叶资源丰富,富含多种营养成分和生物活性成分.杜仲叶及其提取物可改善猪的生长性能、繁殖性能、肉品质及免疫力等.文章就杜仲叶及其提取物的主要成分、功能及在养猪生产中的应用进行综述.

花垣县田成渔港养殖场粪污干湿分离后,干粪打包发酵供猕猴桃园及周围农户菜地施用.粪水进入红泥膜沼气池,产生的沼气做场区能源,沼液经四级沉淀后流入沼液池,通过吸粪车运输到猕猴桃园贮粪池,形成了"猪—沼—果(菜)"粪污综合处理利用模式.

本试验旨在研究饲粮中添加不同水平的桑叶提取物(MLE)对生长猪生长性能、养分表观消化率及血清生化指标的影响.选择体重为(23.84±3.11)kg的健康宁乡猪杂交F1代(杜洛克×宁乡猪)240头,随机分为4个组,每组6个重复,每个重复10头猪.对照组饲喂基础饲粮,3个试验组分别在基础饲粮中添加0.05％、0.10％、0.15％MLE.试验猪自由采食和饮水,预试期5 d,正试期43 d.结果显示:1)随着MLE添加水平的增加,生长猪的末重呈线性增加(P<0.05),平均日采食量(ADFI)和平均日增重(ADG)均呈线性和二次变化(P<0.05).与对照组相比,0.10％和0.15％MLE组生长猪的末重、ADFI和ADG均显著提高(P<0.05).2)生长猪的总能和有机物表观消化率随MLE添加水平的增加呈线性和二次变化(P<0.05);与对照组相比,0.05％、0.10％和0.15％MLE组总能和有机物表观消化率均显著提高(P<0.05);粗脂肪表观消化率随MLE添加水平的增加呈线性增加(P<0.05);粗纤维表观消化率随MLE添加水平的增加呈二次变化(P<0.05).3)生长猪的血清免疫球蛋白A、免疫球蛋白G和免疫球蛋白M含量随MLE添加水平的增加呈线性升高(P<0.05),且0.10％和0.15％MLE组的上述3种免疫球蛋白含量均显著高于对照组(P<0.05).4)生长猪的血清总胆固醇(TCHO)和低密度脂蛋白(LDL)含量随MLE添加水平的增加呈线性降低(P<0.05),0.10％和0.15％MLE组血清TCHO和LDL含量显著低于对照组(P<0.05).由此可见,饲粮中添加MLE能够改善生长猪的生长性能,提高养分表观消化率,增强机体免疫能力,调节血液脂质代谢.在本试验条件下,生长猪饲粮中MLE的适宜添加水平为0.10％.

为评价杜洛克与宁乡猪杂交组合的效果,以21头杜宁杂种猪(杜洛克为父本,宁乡猪为母本)为研究对象,对其胴体性状、肉质性状、肌肉成分相关指标进行测定,并就胴体性状和肉质性状相关性进行了分析.结果显示,宰前体重为(99.00±7.32) kg的杜宁杂种猪,屠宰率为(71.15±1.29)%,眼肌面积为(29.45±2.64) cm2,背膘厚为(38.50±5.85) mm,失水率(15.23±2.56)%,嫩度(4.20±0.86) kgf.背最长肌中检测到21种脂肪酸,饱和脂肪酸含量为(43.15±1.26)%,总不饱和脂肪酸含量为(56.88±1.26)%.肌苷酸含量(2.15±0.23) mg/g.必需氨基酸、鲜味氨基酸、总氨基酸含量分别为(8.99±0.39)%、(14.87±0.58)%、(19.56±0.80)%.相关性分析显示,杜宁杂种猪背膘厚与瘦肉率(r=-0.710)、脂率(r= 0.833)呈极显著相关(P<0.01);滴水损失与pH2 4(r=0.826)、嫩度(r=0. 806)、熟肉率(r=-0.552)呈极显著相关(P<0.01).综合以上结果表明,杜宁杂种猪的胴体、肉质性能良好,背膘厚适中,肌肉保水力强,营养价值丰富且富含鲜味物质,获得了良好的杂交效果.

试验以加系大白母猪为研究对象,分别以引进英系大白冷冻精液和加系大白常温精液配种,统计情期受胎率、分娩率、总产仔数、产活仔数、后代猪仔猪初生个体重、25日龄断奶个体重、达100 kg体重日龄等性状,以测试不同类型精液的配种效果.结果表明:1)冷冻精液组的受胎率(66.67％)、分娩率(57.29％)均极显著低于常温精液组的受胎率(89.44％)、分娩率(80.99％);2)冷冻精液组的总产仔数(10.82头)显著低于常温精液组的总产仔数(15.92头);3)冷冻精液组的初生个体重(1.69 kg)、25日龄断奶个体重(6.42 kg)均显著高于常温精液组的初生个体重(1.38 kg)、25日龄断奶个体重(5.99 kg);4)冷冻精液组后代达100 kg体重日龄(160.72 d)显著高于常温精液组后代(157.41 d),冷冻精液组后代母系指数(100.56)显著低于常温精液组后代(116.26),两组100 kg体重活体背膘厚无显著差异.结论:冷冻精液组后代的初生个体重、25日龄断奶个体重等指标均高于常温精液组,但受胎率、分娩率、总产仔数、产活仔数、达100 kg体重日龄等指标均不如常温精液组,在生产实践中有待进一步验证.

试验旨在测定不同类型猪的肉品质,筛选适合当地环境的生猪品种或组合.采用单因子设计,将初始体重为(31.50±7.85)kg的巴克夏猪×浦市铁骨猪、湘村黑猪和巴克夏猪×巴马香猪分为3组,每组8个重复,每个重复1头,分析胴体性状、肉品质及微量元素、脂肪酸、氨基酸含量.预试期3 d,正试期105 d.结果显示:3个处理组猪的胴体性状指标差异均不显著;熟肉率及24 h贮存损失均为湘村黑猪<巴克夏猪×浦市铁骨猪<巴克夏猪×巴马香猪(P<0.05);湘村黑猪肉中铜含量高于巴克夏猪×巴马香猪(P<0.05),巴克夏猪×浦市铁骨猪肉中镁含量高于巴克夏猪×巴马香猪(P<0.05),湘村黑猪肉中钾含量最低(P<0.05);湘村黑猪α-亚麻酸(C18:3n3)含量最低(P<0.05);3个处理组猪肉中氨基酸含量均在正常范围内(P>0.05).综上,巴克夏猪×浦市铁骨猪的屠宰率、瘦肉率等胴体性状以及氨基酸、脂肪酸含量与湘村黑猪相当,24 h贮存损失优于巴克夏猪×巴马香猪.

为了比较宁乡猪不同杂交组合的优劣,筛选出较为理想的杂交组合,试验设计了巴克夏猪×宁乡猪(巴宁)、杜洛克猪×宁乡猪(杜宁)、巴克夏猪×(巴克夏猪×宁乡猪)(巴巴宁)、(巴克夏猪×宁乡猪)×(巴克夏猪×宁乡猪)(巴宁F1)等4个杂交组合,并进行了胴体、肉质等性状指标的系统测定.结果表明,以宁乡猪为母本的杂种猪均具有较好的胴体性状和较高的肉品质,胴体长、平均背膘厚、瘦肉率、肥膘率、失水率、天门冬氨酸、赖氨酸、肉豆蔻酸、锌等19个指标组间存在显著差异(P<0.05),其中巴宁的失水率显著低于巴宁F1(P<0.05),锌含量显著高于其他3个组合(P<0.05),肉蔻豆酸和十七烷酸含量分别显著高于和低于巴巴宁(P<0.05),甘氨酸含量显著高于杜宁(P<0.05),丙氨酸、苯丙氨酸含量显著高于杜宁、巴巴宁(P<0.05);巴宁F1组合瘦肉率最低、肥膘率最高,与其他3组差异达到显著水平(P<0.05),赖氨酸和天门冬氨酸含量显著高于其他3组(P<0.05).说明巴宁杂交组合猪较为适合市场消费需求.

为探讨广益黑猪的肉质特性,试验选取105 kg左右的健康广益黑猪28头,屠宰后取背最长肌分析肉质性状和营养成分.结果表明,广益黑猪肌肉肉色评分、大理石纹评分和贮存损失分别为3.48、3.13和1.94％;粗蛋白质和肌内脂肪分别为21.80％和3.29％.肌肉中氨基酸总量、鲜味氨基酸含量、必需氨基酸含量以及鲜味氨基酸占总氨基酸比例、必需氨基酸占总氨基酸比例分别为20.89％、16.17％、8.80％、77.41％、42.13％;肌肉总不饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸和饱和脂肪酸含量分别为58.43％、44.61％、13.82％和41.57％;肌肉中钾、钠、镁、钙、铜和锌含量分别为0.40％、390.96 mg/kg、290.07 mg/kg、32.32 mg/kg、0.30 mg/kg和14.84 mg/kg.测定结果显示,广益黑猪具有良好的肌肉品质.