"肉牛育肥散"饲喂效果初试

粗放饲养条件下，将20头供试牛随机分为两组、每组10头，每10d为一个试验期，试验进行了3期。在试验期内其结果为：试验组肉牛的日增重较对照组分别高14．3％、10．7％和10．7％，有极显著差异。从经济效益分析，试验组肉牛头日增重1435g，纯收入3．83元，对照组头日均增重1285g，纯收入3．12元，试验组高出对照组0．71元。试验表明，按规定数量加入“肉牛育肥散”于精料中，可使肉牛增重加快，提高饲料利用率，降低增重成本，从而提高经济效益。     

湿热环境对自由采食生长育肥猪采食行为的影响

本试验旨在研究湿热环境对自由采食情况下生长育肥猪采食行为的影响。试验选取117头平均体重为(30.26±2.19)kg的健康生长猪,随机平均分到9个测定站,每个测定站采用全自动种猪生产性能测定系统和自动温湿度记录仪分别对采食行为和舍内温湿度进行记录。结果表明:生长育肥猪采食行为表现出明显的昼夜节律变化规律,06:00—09:00和15:00—19:00 2个时间段内的采食量、采食次数、采食时间显著高于21:00—04:00(P0.05),其采食行为的52%以上都发生在这2个时段;温度、相对湿度及其互作能极显著影响生长育肥猪的单位体重采食量、采食时间(P0.01),温湿指数的增加能显著降低单位体重采食量(P0.05)。综上,湿热环境对生长育肥猪的采食行为有显著影响;其采食行为呈现昼夜节律变化。     

体外法优化玉米—杂粕型饲粮的非淀粉多糖酶谱及其对育肥猪肠道微生物的影响

【目的】利用体外模拟法优化玉米—杂粕型饲粮的非淀粉多糖（NSP）酶谱,并分析优化的非淀粉多糖酶谱对饲粮养分消化率和育肥猪肠道微生物组成和结构的影响,为饲粮高效利用和精准饲养提供数据支撑和理论参考。【方法】试验一在育肥猪玉米—杂粕型饲粮中分别添加不同水平的木聚糖酶、β-葡聚糖酶、纤维素酶、α-半乳糖苷酶、β-甘露聚糖酶和果胶酶6种NSP酶,采用胃—小肠体外模拟法测定体外回肠干物质消化率（IVIDMD）;取IVIDMD达到最大值时各NSP酶的添加水平为该NSP酶0编码水平,按照六元二次回归正交旋转组合设计,进行体外消化试验,建立IVIDMD与NSP酶添加量的六元二次回归方程,筛选出玉米—杂粕型饲粮最优NSP酶谱（OEC）;利用胃—小肠—大肠体外模拟消化法分析测定添加OEC前后饲粮的体外干物质消化率（IVDMD）、体外能量消化率（IVGED）和体外消化能（IVDE）,以验证OEC的效果。试验二按照单因素完全随机设计,选用16头健康、体重相近去势公猪（117.8 ± 1.66 kg）,随机分为2个处理组,每个处理8头猪,对照组饲喂玉米—杂粕型基础饲粮,加酶组在基础饲粮中添加OEC;在试验开展第18天采用直肠擦拭法采集猪新鲜粪便,利用16S rRNA基因高通量测序对粪便微生物菌群的多样性及相对丰度进行分析,并进行功能预测。【结果】（1）在本试验条件下,玉米—杂粕型饲粮OEC为：纤维素酶1 003 U·kg^-1、木聚糖酶18 076 U·kg^-1、β-葡聚糖酶1 377 U·kg^-1、β-甘露聚糖酶14 765 U·kg^-1、α-半乳糖苷酶337 U·kg^-1和果胶酶138 U·kg^-1;（2）在玉米—杂粕型饲粮中添加OEC使IVDMD由73.44%显著提高到76.26%（P<0.01）,IVGED由74.03%显著提高到76.45%（P = 0.01）,IVDE由14.97 MJ·kg^-1显著提高到15.58 MJ·kg^-1（P<0.01）;（3）在门水平上,共筛选出了12个相对丰度大于0.1%的菌门,其中Bacteroidota（拟杆菌门）、Firmicutes（厚壁菌门）和Spirochaetota（螺旋体门）为优势菌门,三者之和在组内占比达96%以上;（4）在属水平上,饲粮中添加OEC显著增加norank_f_F082,norank_f_Bacteroidales_RF16_group,Bacteroides（拟杆菌属）和Roseburia（氏菌属）的相对丰度（P<0.05）,Eubacterium_ruminantium_group（P = 0.083）有增加的趋势,而Oscillibacter（颤杆菌克）的相对丰度显著降低（P<0.05）,Clostridium_sensu_stricto_1和norank_f__norank_o__WCHB1-41（P = 0.083）有降低的趋势（P = 0.052）。【结论】饲粮中添加体外法优化的NSP酶谱,显著提高了育肥猪玉米—杂粕型饲粮干物质和能量的体外消化率以及体外消化能,增加了纤维分解菌和产丁酸菌等有益菌在育肥猪肠道微生物中的占比,在一定程度上减少了有害菌的数量,优化了肠道微生态。     

高档苎麻服装面料研发中的染整技术问题探讨

本文对苎麻高支细薄织物的丝光、纯苎麻单面印色休闲面料的染整工艺及吸湿快干苎麻针织面料的开发中的某些染整技术问题进行分析讨论,并提出了相关技术建议。     

Preparation and application of an<Emphasis Type="Italic">s</Emphasis>-triazine-based novel<Emphasis Type="Italic">N</Emphasis>-halamine biocide for antimicrobial fibers

N-halamines serve as important antimicrobial agents. Development of this class of compounds has been shown to provide benefits especially from a biocidal point of view. A novels-triazine-basedN-heterocycle, dichloro-m-aminophenyl-hydantoinyl-s-triazine (DAPHT), which could be rendered antimicrobial through exposure to diluted chlorine bleach, was synthesized and characterized by¹H NMR,¹³C NMR, and FT-IR. A finishing method was used to apply theN-halamine precursor onto cotton fabric, and the optimum conditions for finishing were investigated. The DAPHT-treated cotton fabric had durable antimicrobial properties up to 50 standard washing cycles and was rechargeable under normal laundry/bleaching conditions. The antimicrobial efficacy against Gram-positive and Gram-negative bacteria was demonstrated.     

细旦涤麻棉针织物的纤维素酶整理

本文介绍了酶整理技术在细旦涤麻棉针织物上的应用，提出了现在主要三种纤维素酶处理细旦涤麻棉针织物的最佳工艺及效果。     

Effect of maize grain and herbage allowance on estimated metabolizable energy intake and animal performance in beef cattle finishing systems

This study investigated the effects of levels of supplementation with maize grain and herbage allowance (HA) on grass herbage and maize intake, animal performance and grazing behaviour in two replicated grazing experiments with Angus beef cattle in Argentina. In Experiment 1, the response to increasing HA (2·5, 5·0 and 7·5 kg DM herbage 100 kg^?1 live weight (LW) d^?1 with and without 0·5 kg DM maize grain 100 kg^?1 LW d^?1) was investigated. In Experiment 2, the responses to level of maize grain offered (0, 0·5 and 1·0 kg DM maize grain 100 kg^?1 LW d^?1) at an HA of 2·5 kg DM herbage 100 kg^?1 LW d^?1 and an HA of 5·0 kg 100 kg^?1 LW d^?1 without maize grain were assessed. In Experiment 2, soyabean meal was added to control the crude protein concentration in the diet. Two methods were used for intake estimations: pre‐ and post‐feeding herbage mass difference, and the use of the n‐alkane and ¹³C technique. The latter predicted most accurately the metabolizable energy requirements calculated from live weights and liveweight gain of beef cattle attained in each treatment in both experiments. Increasing HA significantly increased herbage intake and liveweight gain (P < 0·01), and general quadratic relationships between these variables could be fitted across experiments despite differences in animal and pasture characteristics. Increasing the amount of maize grain offered significantly reduced herbage intake and grazing time, but increased liveweight gain and digestibility of the diet. Substitution rate increased with increasing HA in Experiment 1 but was not affected by level of maize supplementation in Experiment 2. These relationships will aid the development of grazing management models for Argentinean conditions.     

Genetic Correlations Between Beef Traits Measured on Young Performance Test Bulls and Daughter Milk Yield

In a breeding programme where young potential breeding bulls are reared on performance test stations, selection based on own results can be carried out before test inseminations. Both beef and milk production traits are included in the total merit index used for selection, and estimates of genetic and phenotypic parameters of these traits are therefore of interest for an optimal construction of such indices. Data on first lactation milk records from the field and beef records of potential dairy breeding bulls from the Danish performance test stations were analysed in bivariate animal-sire models using the AI-REML algorithm. Genetic correlations of 0.16, 0.25 and 0.43 between feed intake capacity and protein yield were obtained for Red Danish (RD), Danish Black and White (DBW) and Danish Jersey (DJ), respectively. These correlations were significantly different from zero for the two populations (DBW and DJ). Genetic correlations around zero between feed efficiency and protein yield were obtained for all three populations. Genetic correlations of 0.44, 0.19 and 0.47 between average daily gain and protein yield were obtained for RD, DBW and DJ, respectively. The genetic correlations between protein yield and muscle area was close to zero for DBW, while it was -0.31 for RD. Selection index calculations indicate that indices composed of different beef performance traits can be used as early predictors for milk yield. Selection on such an index could increase the breeding value of the young bulls for milk production traits by 0.8-2.0% of the population mean.     

Short‐term food deprivation before a fish oil finishing strategy improves the deposition of n‐3 LC‐PUFA,but not the washing‐out of C18 PUFA in rainbow trout

This study aimed to test the hypothesis that the efficiency of a finishing period can be improved by reducing the initial fat content of fish fillets, by means of a period of food deprivation. Two groups of rainbow trout (Oncorhynchus mykiss) were fed for an 18‐week grow‐out period on a vegetable oil‐based diet (VO) or a fish oil‐based diet (FO). VO fed fish were then split into two sub groups: one (VO/FO) was shifted to the FO diet for 8 weeks, whilst the other (UF/FO) was deprived of food (unfed) for 2 weeks and then fed the FO diet for the remaining 6 weeks. The control treatment (FO/FO) was represented by fish continuously fed FO. The subsequent reduction of total fat in the UF/FO treatment was then responsible for a much faster recovery towards a FO‐like fatty acid profile, validating the proposed hypothesis. However, the modification of the fatty acid composition of fish fillets during the feed withholding period, coupled with the postponement of the finishing diet, resulted in only minor beneficial effects of this strategy, and the loss of potential weight gain. However, the n‐3 LC‐PUFA content in UF/VO fish fillets was significantly higher than fish subjected to the VO/FO treatment.     

双低菜籽粕饲喂生长肥育猪的效果研究

[目的]研究应用双低菜籽粕代替豆粕饲喂生长育肥猪的效果。[方法]试验选择长白（♂）与八眉猪（♀）杂交一代母猪,再与长白公猪（♂）杂交所产三元仔猪共60头,随机分4组,即试验Ⅰ、Ⅱ、Ⅲ和Ⅳ组,日粮中分别用0、6%、10%和14%的双低菜籽粕取代日粮中的豆粕。[结果]试验Ⅳ组的日增重极显著低于其他3组日增重（P〈0.01）,而试验Ⅰ、Ⅱ和Ⅲ组之间差异不显著;通过对血液中谷丙转氨酶（ATL）、谷草转氨酶（AST）;甲状腺激素（TSH）、甲状腺素（T4）和三碘甲腺原氨酸（T3）指标测定,各试验组间差异不显著。[结论]选用10%双低菜籽粕取代豆粕蛋白饲粮饲喂生长育肥猪效果最好。