车前子中黄酮提取物对油脂的抗氧化活性研究

以车前子为原料超声强化乙醇提取黄酮,通过单因素和正交试验获得最佳工艺条件,研究了黄酮提取物对油脂的抗氧化性能及对羟基自由基的清除能力并与常用的抗氧化剂VC和柠檬酸比较。结果表明,在30%乙醇、料液比1∶40、超声温度60℃、超声强化处理60 min的最佳工艺条件时,车前子中黄酮的提取率为2.8%,该提取物对羟基自由基的清除作用随浓度增大而增强,对油脂有较强的抗氧化活性,抗氧化能力接近VC与柠檬酸,当油脂在烘箱放置时间延长使氧化程度加深时,黄酮对动物油的保护作用愈加显著,所以车前子黄酮提取物更宜于作为动物油的天然抗氧化剂添加于油脂及含油食品中。     

淡豆豉异黄酮浓缩物对大鼠胰岛素抵抗的改善作用

目的:观察淡豆豉异黄酮浓缩物对大鼠胰岛素抵抗(IR)的改善作用。方法:采用高糖高脂饲料喂养加小剂量链脲佐菌素(STZ)腹腔注射的方法建立IR大鼠模型,8周后测定糖耐量(GTT),留取空腹血清测定血糖(FPG)、胰岛素(FINS)和糖化血红蛋白(GHb),计算胰岛素敏感指数(ISI)。结果:淡豆豉异黄酮浓缩物能明显改善IR大鼠GTT,明显降低FPG,FINS和GHb,显著增加ISI。结论:淡豆豉异黄酮浓缩物对大鼠胰岛素抵抗有明显的改善作用。     

HPLC法测定不同产地火麻仁中五种脂肪酸含量

目的:采用高效液相色谱法对不同产地火麻仁药材中五种主要脂肪酸(α-亚麻酸、亚油酸、油酸、棕榈酸、硬脂酸)进行含量测定,据此对不同产地火麻仁的优劣进行评价。方法:采用Agilent EclipseXDB-C18色谱柱(150mm×4.6mm,5μm),以甲醇-水(85∶15)为流动相,流速1.0mL.min-1,检测波长210nm,柱温30℃。在此条件下,该五种脂肪酸的甲酯化产物与其他组分得到良好的分离,α-亚麻酸甲酯、亚油酸甲酯、油酸甲酯、棕榈酸甲酯和硬脂酸甲酯的进样量分别在42 168μg(r=0.9998)、67267μg(r=0.9995)、9.7 39μg(r=0.9995)、23 94μg(r=0.9996)和14 56μg(r=0.9997)范围内与各自峰面积积分值呈良好线性关系;平均加样回收率分别为99.5%(RSD=0.65%,n=6)、99.5%(RSD=1.20%,n=6)、99.2%(RSD=0.41%,n=6)、99.0%(RSD=0.60%,n=6)和99.5%(RSD=0.61%,n=6)。结论:该法操作简便,结果可靠。不同产地火麻仁油脂中的脂肪酸含量的确具有一定差异,以保定地区的脂肪酸含量为最高,可为火麻仁油脂的合理开发利用提供相关借鉴。     

Characterization of semen type prevalence and allocation in Holstein and Jersey females in the United States

Our objective was to characterize semen type prevalence and allocation to inseminate US Holstein and Jersey females by year, parity, service number, and herd size. A secondary objective was to identify the prevalence of beef breed sires selected to create beef × Holstein and beef × Jersey crossbred calves. The final data set included 8,244,653 total inseminations of 4,880,752 Holstein females across 9,155 herds, and 435,267 total inseminations of 266,058 Jersey females across 2,759 herds from October 2019 to July 2021. This data set represents approximately 42 and 27% of the total dairy cows and heifers, respectively, across approximately 40% of the total licensed dairy herds in the continental United States. Holstein and Jersey females were inseminated with 1 of 4 semen types: (1) beef, (2) conventional, (3) sexed, or (4) other dairy. The top 4 beef breeds used to produce beef × Holstein and beef × Jersey crossbred calves, respectively, were Angus (55.1 and 39.1%), Limousin (13.9, and 23.5%), Simmental (11.7 and 20.5%), and Crossbreed Beef (11.3 and 4.8%). From 2019 to 2021, the use of sexed semen to inseminate Holstein and Jersey females increased from 11.0 and 24.5% to 17.7 and 32.1%, respectively, and the use of beef semen to inseminate Holstein and Jersey females increased from 18.2 and 11.4% to 26.1 and 21.2%, respectively. The use of beef semen to inseminate Holstein and Jersey females increased with increasing parity and service number, whereas the use of sexed semen decreased with increasing parity and service number supporting that farmers used sexed semen more aggressively in higher fertility and younger females with greater genetic merit. Overall, the increase in sexed and beef semen inseminations was driven primarily by larger herds. In conclusion, sexed and beef semen inseminations in US Holstein and Jersey females increased from 2019 to 2021 and was allocated differentially based on parity and service number. This increase was driven primarily by larger dairy herds possibly due to differences in reproductive performance and economies of scale.     

ZJS88－1型杏仁软皮脱皮机的研制

杏仁是人们喜爱的营养保健食品，杏仁软皮的脱除是杏仁加工中要解决的关键问题。本文论述了杏仁软皮的摩擦脱除机理，介绍了ＺＪＳ８８－１型杏仁软皮脱皮机柔性硬摩擦装置及脱皮机结构材点。生产试用及其机器性能测试结果表明：该脱皮机结构合理，性能良好，并适用于类似食品的脱皮加工，具有较广的使用价值。     

Genomic and pedigree estimation of inbreeding depression for semen traits in the Basco-Béarnaise dairy sheep breed

Inbreeding depression is associated with a decrease in performance and fitness of the animals. The goal of this study was to evaluate pedigree-based and genomic methods to estimate the level of inbreeding and inbreeding depression for 3 semen traits (volume, concentration, and motility score) in the Basco-Béarnaise sheep breed. Data comprised 16,196 (or 15,071) phenotypic records from 620 rams (of which 533 rams had genotypes of 36,464 SNPs). The pedigree included 8,266 animals, composed of the 620 rams and their ancestors. The number of equivalent complete generations for the 620 rams was 7.04. Inbreeding coefficients were estimated using genomic and pedigree-based information. Genomic inbreeding coefficients were estimated from individual SNP and using segments of homozygous SNP (runs of homozygosity, ROH). Short ROH are of old origin, whereas long ROH are due to recent inbreeding. Considering that the equivalent number of generations in Basco-Béarnaise was 6, inbreeding coefficients for ROH with a length >4 Mb refer to all (recent + old) inbreeding, those with a length >17 Mb correspond to recent inbreeding, and the difference between them indicates old inbreeding. Pedigree-based inbreeding coefficients were also estimated classically, or accounting for nonzero relationships for unknown parents, or including metafounder relationships (estimated using markers) to account for missing pedigree information. Finally, inbreeding coefficients combining genotyped and nongenotyped animal information were computed from matrix H of the single-step approach, also including metafounders. Inbreeding depression was estimated differently depending on the approach used to compute inbreeding coefficients. These 8 estimators of inbreeding coefficients were included as covariates in different animal models. No inbreeding depression was detected for sperm volume or sperm concentration. Inbreeding depression was significant for the motility of spermatozoa. The effect of old and recent inbreeding on motility was null and negative, respectively, demonstrating the existence of purging by selection of deleterious recessive alleles affecting motility. A 10% increase in inbreeding would result in a reduction in mean motility ranging between 0.09 and 0.22 points in the score (from 0 to 5). Motility is unfavorably affected by increasing recent inbreeding but the impact is very small. Runs of homozygosity and metafounders allow us to accurately estimate inbreeding depression and detect recent inbreeding.     

Genetic consequences of terminal crossbreeding,genomic test,sexed semen,and beef semen in dairy herds

The development of breeding tools, such as genomic selection and sexed semen, has progressed rapidly in dairy cattle breeding during the past decades. In combination with beef semen, these tools are adopted increasingly at herd level. Dairy crossbreeding is emerging, but the economic and genetic consequences of combining it with the other breeding tools are relatively unknown. We investigated 5 different sexed semen schemes where 0, 50, and 90% of the heifers; 50% of the heifers + 25% of the first-parity cows; and 90% of the heifers + 45% of the first-parity cows were bred to sexed semen. The 5 schemes were combined in scenarios managing pure-breeding or terminal crossbreeding, including genomic testing of all newborn heifers or no testing, and keeping Swedish Red or Swedish Holstein as an initial breed. Thus, 40 scenarios were simulated, combining 2 stochastic simulation models: SimHerd Crossbred (operational returns) and ADAM (genetic returns). The sum of operational and genetic returns equaled the total economic return. Beef semen was used in all scenarios to limit the surplus of replacement heifers. Terminal crossbreeding implied having a nucleus of purebred females, where some were inseminated with semen of the opposite breed. The F₁ crossbred females were inseminated with beef semen. The reproductive performance played a role in improving the benefit of any of the tools. The most considerable total economic returns were achieved when all 4 breeding tools were combined. For Swedish Holstein, the highest total economic return compared with a pure-breeding scenario, without sexed semen and genomic test, was achieved when 90% sexed semen was used in heifers and 45% sexed semen was used for first-parity cows combined with genomic test and crossbreeding (+€58, 33% crossbreds in the herd). The highest total economic return for Swedish Red compared with a pure-breeding scenario, without sexed semen and genomic test, was achieved when 90% sexed semen was used in heifers combined with genomic test and crossbreeding (+€94, 46% crossbreds in the herd). Terminal crossbreeding resulted in lower genetic returns across the herd compared with the corresponding pure-breeding scenarios but was compensated by a higher operational return.     

Ziziphi spinosae Semen Oil Enhance the Oxidative Stability of Soybean Oil under Frying Conditions

The objective of this study is to improve the oxidative stability of soybean oil by using Ziziphi spinosae semen oil (ZSSO). In the present study, the oxidative stability, fatty acid composition, tocopherol, and phenolic changes of soybean oil without additives and soybean oil mixed with 5% ZSSO are evaluated during frying at 180 ℃ for 18 h. Tert-butyl hydroquinone (TBHQ) and vitamin E (VE) as common antioxidants are incorporated into soybean oil for comparison. According to the results of oxidative stability assays of conjugated diene value, thiobarbituric acid value, acid values, and total polar compounds, the incorporation of ZSSO significantly restrain the lipid oxidation of soybean oil. After 18 h of frying, the soybean oil samples with ZSSO has more polyunsaturated fatty acids, tocopherols, and DPPH radical scavenging capacity, and less trans fatty acids, compared with TBHQ and VE. In addition, ZSSO-containing soybean oil maintains a high content of phenols during the frying period, which is correlated with the increase in oxidative stability. Therefore, replacing part of soybean oil with ZSSO can effectively reinforce the performance of soybean oil under frying conditions.     

响应曲面法优化超声提取韭菜籽油的工艺研究

试验首先通过单因素试验分析了提取剂种类、液料比、超声功率、超声时间和超声温度对得率的影响,然后在此基础上采用Box-Behnken设计对超声提取韭菜籽油工艺中的液料比、超声时间和超声温度3因素的最优化组合进行了定量研究,建立并分析了各因素与得率关系的数学模型。结果表明:最佳的工艺条件为液料比11.9mL/g,超声时间59m in和超声温度58℃。经试验验证,在此条件下,得率为22.41%,与理论计算值22.48%基本一致。说明回归模型能较好地预测韭菜籽油的提取得率。     

Exploring the impact of sexed semen on the structure of the dairy industry

Widespread commercial application of sexed semen is expected within the next decade because of continued improvements in fertility of sexed semen and sorting capacity. The objective of this study was to explore the potential impact of widespread application of sexed semen on the structure of the dairy industry in the United States. Historically, female offspring from all heifers and cows were needed to produce enough dairy replacement heifers to replace culled cows. The use of sexed semen allows for a decoupling of breeding decisions necessary to obtain an adequate supply of dairy replacement heifers from those needed to achieve pregnancies needed to start new lactations. Application of sexed semen allows dairy producers to select among their herds’ potential dams and produce dairy replacement heifers from only the genetically superior animals. The rate of genetic progress is expected to increase, but not more than 15% of the rate of gain accomplished through sire selection achieved through conventional (nonsexed) artificial insemination breeding. The supply of dairy replacement heifers is expected to grow to meet and temporarily exceed current demand, resulting in reduced prices for dairy replacement heifers. Consequently, herd turnover rates are expected to increase slightly, and herd expansions may accelerate. The rate of consolidation of dairy farms is expected to increase. Widespread application of sexed semen may temporarily increase the supply of milk, which would result in lower milk prices. The cost of milk production will be reduced as well. Many breeding options exist for the genetically poorer cows in the herd. The optimal breeding mix depends on the value of the various kinds of calves that could be produced. More crossbred calves for beef production may be produced; however, a market for these crossbred calves is not well established. Increased specialization is expected with more dairy producers deciding not to raise their own heifers but to purchase replacements. Other dairy farms might specialize in producing genetically superior dairy replacement heifers for sale. Depending on the value of calves not raised for replacements, artificial insemination organizations might market beef conventional semen or beef male sexed semen to dairy farms. The use of sexed semen should lower the cost of progeny-testing programs and embryo transfer and enhance the value of genetic markers. Eventually, the economic benefits from the use of sexed semen will be passed on to consumers.