饲粮精料水平和蛋氨酸铬添加剂量对舍饲滩羊生长性能、屠宰性能、肉品质和脂肪沉积的影响

本试验旨在探究饲粮精料水平和蛋氨酸铬(Cr-Met)添加剂量对舍饲滩羊生长性能、屠宰性能、肉品质和脂肪沉积的影响。采用2×3双因素试验设计,2个因素分别为饲粮精料水平和Cr-Met添加剂量,其中饲粮精料水平分别设为35%(低精料饲粮,饲粮精粗比为35∶65)和55%(高精料饲粮,饲粮精粗比为55∶45),Cr-Met添加剂量分别设为0、0.75和1.50 g/(d·只)。将60只雄性滩羊羔羊[平均体重为(21±1)kg]随机分配到6个试验组,每组10只。试验期为80 d,其中预试期15 d,正试期65 d。结果显示:1)与低精料饲粮组相比,高精料饲粮组滩羊的平均日增重、屠宰率、背膘厚度、肌内脂肪含量和后腿肉比重显著增加(P<0.05),但料重比与肌肉蒸煮损失、剪切力、pH、亮度(L*)值、红度(a*)值和黄度(b*)值则显著降低(P<0.05)。2)低精料饲粮组滩羊背膘厚度、皮下脂肪厚度、肌内脂肪含量和后腿肉比重随Cr-Met添加剂量的增加而线性降低(P<0.05),但肌肉pH则线性升高(P<0.05)。3)高精料饲粮组滩羊肋肉比重、腰肉比重以及肌肉剪切力和pH随Cr-Met添加剂量的增加而线性升高(P<0.05),而肌内脂肪含量和肌肉a*值则线性降低(P<0.05)。综合本试验测定指标,建议在滩羊养殖中选择精粗比为55∶45的高精料饲粮,Cr-Met的适宜添加剂量为1.50 g/(d·只),且不建议在精粗比为35∶65的低精料饲粮中添加Cr-Met。     

蛋鸡脂肪肝综合征模型的建立

试验旨在建立蛋鸡脂肪肝综合征病理模型。选取5日龄的海兰褐蛋鸡公雏280只，随机分为对照组（基础日粮组）和3个模型组（A、B、C组），试验第1~10天给模型组饲喂不同配比的高脂饲料，第11~20天饲喂常规基础日粮，每天观察并记录试验鸡精神状态、外观体征、饮水量和食欲情况，试验第0、10、20天从各组随机抽取15只鸡进行翅静脉采血并剖取肝脏和腹脂，测定肝脏系数、肝脂率、腹脂率，血清总胆固醇（TC）、甘油三酯（TG）、谷丙转氨酶（ALT）和谷草转氨酶（AST）水平。结果显示，试验第10天，3个模型组剖检时可见腹腔和肠系膜有大量的脂肪沉积，肝脏系数、肝脂率和腹脂率，以及血清中总胆固醇、甘油三酯、谷丙转氨酶和谷草转氨酶指标均符合鸡脂肪肝综合征模型的诊断标准；试验第20天，模型A、B组谷丙转氨酶和谷草转氨酶水平有所恢复，其他指标仍高于对照组，而模型C组的临床症状和各项检测指标仍符合鸡脂肪肝综合征模型的诊断标准。因此采用连续饲喂高脂饲料C（74.5%基础日粮、6%胆固醇、14%猪油、5%蔗糖、0.5%丙基硫氧嘧啶）可成功建立蛋鸡脂肪肝综合征模型。     

Markers for Predicting Overweight or Obesity of Broodmares

Obesity has become of great concern to all equine community from both veterinary and welfare points of view. For estimating obesity markers of brood mares, 17 mares with body conditions were subjected to blood sampling and ultrasound examination to measure rump fat for 6 consecutive weeks. Body length (L), girth (G), and height (H) were measured to estimate body weight (BW), body fat %, body fat mass (BFM) and body mass index (BMI). Mares were classified into three groups according to body condition score (BCS) and rump fat thickness (RF). Overweight mares (O) had BCS >7 and RF >7 mm, moderate (M) had BCS and RF >3 to ≤7, and emaciated (E) had BCS and RF ≤ 3 mm. Glucose, triglycerides, nitric oxide (NO), insulin, insulin-like growth factor-I (IGF-1), leptin, ovarian hormones, and thyroid hormones were measured. Results revealed that BCS, G, L, L × G × H, BW, RF, fat %, and BFM correlated significantly (P < .0001) with body condition. Tetraiodothyronine concentrations of E mares were significantly high (P = .04), but triiodothyronine concentrations tended (P = .07) to be low. Insulin (P = .06) and IGF-1 (P = .07) concentrations tended to be high in O mares. Moderate mares had the highest leptin concentrations (P = .007), but E mares had the lowest P4 concentrations (P = .01). Overweight mares had nonsignificantly high glucose, NO, and triglycerides. In conclusion, back fat and morphometric measurements are the easiest and simple assessment of overweight and obesity. Obese and overweight mares showed slight hyperinsulinemia, hypertriglyceridemia, and hyperglycemia. Hyperleptinemia alone is not indicative of obesity.     

两种油脂对小鼠皮肤创伤修复作用研究

本研究旨在观察阿勒泰大尾羊尾脂油脂对损伤皮肤是否具有修复作用，并与牛油脂、市售商品做比较。研究选择40 只体重在31 ± 1 g 之间的昆明小鼠，雌雄各半，通过构建小鼠皮肤损伤模型，将小鼠分为4 组（羊尾油组、牛油组、市售商品组和空白组）进行试验观察。小鼠皮肤伤口愈合良好，雌鼠的创面愈合能力强于雄鼠，雌鼠伤口愈合速度：羊尾油组＞牛油组＞市售商品组＞空白对照组。雄鼠伤口愈合速度：羊尾油组＞市售商品组＞牛油组＞空白对照组。皮肤组织病理学结果显示，涂抹羊尾脂、牛油脂、市售商品与空白对照处皮肤相比，创伤修复组织中脂肪细胞、胶原纤维以及其他细胞的数量、排列分布均有差异。羊尾油和牛油均有修复皮肤创伤的作用，且羊尾油修复作用更强，羊尾油可通过促进胶原纤维的生成加速皮肤修复。     

脂肪含量对再制片状干酪品质的影响

研究不同脂肪含量和脂肪替代物对再制片状干酪品质的影响。对5 种不同脂肪含量再制片状干酪的基本理化指标、色泽、质构和感官品质进行测定和评估。结果表明：5 种不同脂肪含量的再制片状干酪pH值、蛋白质和脂肪含量存在显著性差异，酶解浓缩黄油的添加对再制片状干酪亮度值、红度值和黄度值均有明显影响；用酶解浓缩黄油替代全部黄油的减脂50%干酪全质构特性与其他组样品有差异，酶解浓缩黄油部分替代黄油制备的4号减脂干酪全质构特性除凝聚性、回复性外，与1～3号干酪无显著差异；通过感官评定发现，酶解浓缩黄油替代全部黄油的减脂50%干酪（5号）感官评分最低，酶解浓缩黄油部分替代黄油的减脂50%干酪（4号）风味和滋味有所增强，总体得分与全脂干酪产品无显著差异。因此通过降低黄油含量，并添加酶解浓缩黄油可提升减脂再制片状干酪的品质。     

Relationships Between Measurements of Body Fat in Thoroughbred Horses

Equine obesity is increasing in prevalence, and weight loss diets are frequently recommended for these horses. However, there are also management situations in which horses are deemed to be too thin. To monitor the efficacy of weight change programs, estimates of body fat are often made. There are several systems available to estimate body fat, and there are benefits and challenges to using each method. The objective of this study was to compare four different methods of estimating body fat in Thoroughbred horses. In 14 mature Thoroughbred horses, relationships among body condition score (BCS), morphometric measurements, ultrasonic measures of subcutaneous fat depots, and estimation of total body fat (BF_D) via measurement of total body water through deuterium oxide dilution were evaluated. Body condition scores ranged from 4.5 to 6.5 on a 9-point scale. Body condition score, heart girth-to-body weight ratio, and BF_D were all positively correlated with each other (P < .05). Subcutaneous fat depth at the tailhead tended to be positively related to BF_D when only horses with BCS ≥ 5 were included (P = .0680). These data suggest that BCS remains a simple means of monitoring adiposity in mature horses in moderate condition. Tailhead fat depots may become useful for monitoring changes in body fat in Thoroughbreds with a BCS above 5, although more work with animals of higher adiposity is required and at different times of year.     

豫南茶树种质资源籽实脂肪含量及脂肪酸组成分析

以豫南地区42份茶树种质资源的茶籽为研究对象,分析了茶籽含仁率及茶籽仁的脂肪含量,范围分别在33.53%~71.60%、17.77%~38.39%。利用气-质联用技术（GC-MS）检测了茶籽仁中的脂肪酸组成和含量,共检测到21种脂肪酸,其中主要成分棕榈酸、硬脂酸、顺-油酸、亚油酸和α-亚麻酸的含量分别在2.64%~5.70%、0.21%~1.11%、7.33%~17.29%、0.09%~8.44%和0.01%~0.15%;相关性分析显示,顺-油酸与十三碳酸、十四碳酸和顺-二十碳二烯酸的含量呈极显著负相关,亚油酸与反-油酸、顺-二十二碳六烯酸含量呈极显著负相关;除了水仙7202茶籽仁中的饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸含量比值为3.08∶12.16∶1,其余茶树种质资源茶籽仁中,这三类脂肪酸的比值均约为1∶2.69∶1.37。中黄1号、农抗早、迎霜、鄂茶11号、龙井43、中选8号、崂山3号和黄金叶8个茶树品种,不仅含仁率和脂肪含量较高,而且茶籽仁脂肪酸的组分和含量丰富、均衡,可初步筛选出来作为豫南地区叶籽两用茶园的候选品种。     

淀粉与油脂对妊娠母猪糖脂代谢及其繁殖性能影响的研究进展

妊娠后期随着胎儿生长速度和乳腺发育加快，母猪机体代谢强度逐渐增加，机体糖脂代谢失衡，出现代谢紊乱。能量占整个日粮成分的70%以上，选择适当的日粮能量来源以调节糖脂代谢的平衡是提高母猪繁殖效率的有效方法。淀粉与油脂作为母猪日粮主要能量来源，均可显著影响后备母猪的初情期启动或经产母猪的繁殖性能，但以母猪本身的糖脂代谢特征为出发点，评述不同来源与水平的淀粉或油脂对母猪繁殖性能的影响鲜有总结报道。文章首先综述了母猪妊娠期糖脂代谢特点和代谢机制，简述了妊娠期代谢紊乱对母猪繁殖性能的不良影响，介绍了淀粉与油脂在母体的吸收及代谢特点，对比分析了不同水平与来源的淀粉和油脂对母猪产仔性能和泌乳性能的影响。最后，为最大化提高猪场经济效益，根据实际生产目的，总结了选择合适能量来源的依据。该综述旨在选择日粮适宜水平和来源的淀粉和油脂以期为提高母猪繁殖效率提供数据支持和理论指导。     

Effect of melatonin on visceral fat deposition,lipid metabolism and hepatic lipo-metabolic gene expression in male rats

Melatonin (MT) influences lipid metabolism in animals; however, the mechanistic effect of melatonin on liver fat and abdominal adipose deposition requires further clarity. In order to study the effects of melatonin on lipid metabolism, and hepatic fat and abdominal adipose deposition in animals, twenty Sprague–Dawley (SD) rats of 6 weeks of age with similar bodyweight were randomly divided into two groups: control (CTL) and MT-treated (10 mg/kg/day). During a 60-day experiment, food intake and bodyweight were measured daily and weekly respectively. At the end of treatment, blood samples were collected to collect plasma to quantify hormones and metabolic indicators of lipid metabolism. In addition, organ and abdominal adipose depots including liver, and omental, perirenal, and epididymal fat were weighed. Liver tissue was sampled for sectioning, long-chain fatty acid (LCFA) quantification, and gene chip and Real-time quantitative PCR (qPCR) analyses. The results showed that liver weight and index (ratio of liver weight to body weight) in MT group reduced by 20.69% and 9.63% respectively; omentum weight and index reduced by 59.88% and 54.93% respectively, and epididymal fat weight reduced by 45.34% (p = 0.049), relative to CTL. Plasma lipid indices, triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL) and total cholesterol (TC) with MT treatment decreased significantly compared with the control. Fat and 8 LCFA content in liver in MT group also decreased. Gene chip and qPCR demonstrated that there were 289 genes up-regulated and 293 genes down-regulated by MT. Further analysis found that the mRNA expression of lipolysis-related genes increased, while the mRNA expression of lipogenesis-related enzymes decreased (p < 0.05) with MT. This study concluded that melatonin greatly affected fat deposition, and hepatic LCFA supply and the expression of genes associated with lipogenesis and lipolysis.     

奶牛乳脂性状候选基因EEF1D突变位点功能分析

提高乳脂含量、提升奶质已成为当前奶牛业研究的重点方向之一。前期经GWAS方法研究发现,EEF1D基因5'非翻译区(5'-UTR)的G/A突变与乳脂率极显著相关,为了进一步对候选基因EEF1D的突变位点进行功能分析,首先通过人工合成获得了EEF1D基因突变型与野生型片段,并在细胞水平上对其开展了功能验证实验。研究发现,EEF1D基因5'-UTR的G/A突变引起Sp3转录起始位点后移33 bp,并且突变型的活性大约是野生型的3倍。研究结果表明,该突变可改变转录因子的转录起始位点,从而使EEF1D的表达上调。