甲酸对二色胡枝子青贮品质的影响

以二色胡枝子(Lespedeza bicolor Turcz.)为青贮原料,研究甲酸添加量(0、2、4、6 mL/kg鲜重)对其青贮品质的影响,以期为二色胡枝子的有效利用提供科学依据。结果表明:随甲酸添加量的增加胡枝子青贮料中pH值和氨态氮含量以及干物质损失率均呈降低趋势,而且贮料中的水溶性糖逐渐增加;添加甲酸能显著降低青贮料中NDF和ADF的含量(P<0.05);6mL/kg甲酸组对抑制青贮发酵效果最明显,有机酸产量最低;随甲酸添加量的增加,青贮料中丁酸的含量也增加,使青贮料的发酵品质有所降低。     

银翘天甘含药血清制备工艺的优化

本研究通过单因素试验和响应面分析设计优化银翘天甘醇提物制剂含药血清的制备工艺,研究采血时间、给药次数及给药浓度对小鼠血清中绿原酸含量的影响。结果表明,银翘天甘醇提物制剂含药血清最佳制备工艺条件为:给药浓度为0.024 g/mL,给药4次,于最后一次给药后33 min采血。此条件下含药血清中绿原酸含量达到33.34μg/mL。     

两种方法所获鸭破骨细胞数量及活性比较

对直接从鸭骨髓腔机械分离的成熟破骨细胞（osteoclasts,OC）和由鸭骨髓来源单核细胞融合成的OC样多核巨细胞（multinucleatedgiantcells,MNGCs）进行培养,分别进行抗酒石酸酸性磷酸酶（tartrate-resistantacidphosphatase,TRAP）染色并计数,扫描电镜观察象牙片吸收陷窝,比较了2种方法获得0C的骨吸收功能。结果显示,2种方法均能分离培养出TRAP阳性且具有骨吸收功能的多核OC,但直接分离获得的成熟OC骨吸收功能更强。     

蓟马取食对苜蓿氨基酸组成及含量的影响

为了探究蓟马取食对苜蓿(Medicago sativa L.)氨基酸组成及含量的影响,本研究以'草原2号'(Medicago varia Martin.'Caoyuan No.2')感蓟马品种和'草原4号'(Medicago sativa L.'Caoyuan No.4')抗蓟马品种为材料,分别进行牛角花齿蓟马(Odo...     

1株具有免疫增强功能的乳酸菌筛选及其免疫效果评价

为筛选出具有较强免疫功能的益生菌用于临床研究,对分离自健康鸡粪便样品中的20株乳酸菌进行耐酸、耐胆盐、体外抑菌、黏附、胞外多糖含量测定试验以及小鼠免疫功能检测,并结合上述试验结果进行综合性评价.结果:筛选出20号菌株为目的菌株,耐酸、耐胆盐试验表明,该菌株在pH=2时的存活率为72.7％,在胆盐浓度为1.0％的环境中存...     

Effects of calcium salts of long-chain fatty acids and rumen-protected methionine on plasma concentrations of ghrelin, glucagon-like peptide-1 (7 to 36) amide and pancreatic hormones in lactating cows

Our objective was to determine the effects of calcium salts of long-chain fatty acids (CLFAs) and rumen-protected methionine (RPM) on plasma concentrations of ghrelin, glucagon-like peptide-1 (7 to 36) amide, and pancreatic hormones in lactating cows. Four Holstein cows in midlactation were used in a 4 by 4 Latin square experiment in each 2-wk period. Cows were fed corn silage-based diets with supplements of CLFAs (1.5% added on dry matter basis), RPM (20 g/d), CLFAs plus RPM, and without supplement. Jugular blood samples were taken from 1 h before to 2 h after morning feeding at 10-min intervals on day 12 of each period. CLFAs decreased dry matter intake, but RPM did not affect dry matter intake. Both supplements of CLFAs and RPM did not affect metabolizable energy intake and milk yield and composition. Plasma concentrations of NEFAs, triglyceride (TG), and total cholesterol (T-Cho) were increased with CLFAs alone, but increases of plasma concentrations of TG and T-Cho were moderated by CLFAs plus RPM. Calcium salts of long-chain fatty acids increased plasma ghrelin concentration, and the ghrelin concentration with CLFAs plus RPM was the highest among the treatments. Plasma concentrations of glucagon-like peptide-1, glucagon, and insulin were decreased with CLFAs, whereas adding RPM moderated the decrease of plasma glucagon concentration by CLFAs. These results indicate that the addition of methionine to cows given CLFAs increases plasma concentrations of ghrelin and glucagon associated with the decrease in plasma concentrations of TG and T-Cho.     

Comparative nucleotide sequence analysis of the phosphoprotein gene of peste des petits ruminants vaccine virus of Indian origin

The nucleotide sequences of the phosphoprotein (P) gene of peste des petits ruminants (PPRV) vaccine virus (PPRV Sungri/96) belongs to Asian lineage have been determined and the deduced amino acid sequences were compared with another vaccine strain PPRV/Nigeria75/1 and with those of the other morbilliviruses. The 1652 nucleotides of the P gene encode a phosphoprotein of 509 amino acid residues (from nucleotide numbers 60 to 1587), which is 91% identical to that of PPRV/Nigeria75/1. The C protein consists of 177 amino acid residues and is 91% identical with that of PPRV/Nigeria75/1. The conserved mRNA editing site (5'TTAAAAGGGCACAG) was present at positions 742-756 in the P gene, which is conserved in all other morbilliviruses. The CTT trinucleotide sequence is present at the N/P and P/M intergenic region, which is totally conserved in morbilliviruses. This will be the third sequence for the P gene of PPRV since that of the vaccine strain and a wild-type Turkish isolate has been published already.     

糖蜜酒精废液处理过程中生成的微生物蛋白的最佳水解条件研究

通过实验选择复合蛋白酶水解糖蜜酒精废液处理过程中生成的微生物蛋白,并通过正交试验分析得到最佳水解条件为水解酶加入量5.5g/150mL,水解温度65℃,pH值5和水解时间5h。     

道塞特、萨福克与阿勒泰羊5月龄杂交公羔肉品质分析

选取5月龄萨福克×阿勒泰(SAF1、SAF2)、道塞特×阿勒泰(DAF1、DAF2)杂交一、二代羔羊与同龄阿勒泰羊(ALT)各3只,对肉品质进行分析。结果表明:5月龄杂交羔羊肉品质得到明显改善,特别是蛋白质、脂肪和氨基酸含量变化尤为明显,且杂交二代优于杂交一代,杂交组合SA优于DA。     

Supplementing rumen‐protected methionine to lactating multiparous dairy cows did not improve reproductive performance

There is evidence that supplementing methionine has positive effects on uterine environment, oocyte quality and embryo development in cattle. Thus, the objective of this study was to evaluate reproductive traits of cows supplemented with rumen‐protected methionine (RPM) during early to mid‐lactation in comparison with an untreated control group (CON). An additional focus was on the effect of puerperal diseases on reproductive performance parameters in RPM‐supplemented group MET and in CON. A total of 1,709 multiparous Holstein‐Friesian cows were enrolled in this field trial conducted on a commercial dairy farm in Slovakia. Cows were allocated at approximately 12 days post‐partum (dpp) to either CON or MET, the latter supplemented with 25.0 g–27.2 g RPM per cow per day incorporated into the total mixed ration (TMR) until leaving the study pen at approximately 140 dpp. The amount of RPM was calculated based on individual feed ingredients analysis and adjusted during the study period when TMR changed. Cows were monitored during the post‐partum period by vaginal examination (day 5 pp), measuring of beta‐hydroxybutyrate in blood (3, 5, and 8 dpp) and by vaginal examination, uterine cytology and measuring of back fat thickness by ultrasound (all at 31 ± 3 dpp). Compared with CON, cows supplemented with RPM did not show better reproduction performance parameters (first service submission rate, days to first service, conception risk, days open 140). Results from binary logistic regression model for the risk of conception showed that metritis had a significant effect, but the supplementation of methionine had not. Results of Cox regression analysis for the odds of conception within 140 dpp revealed only metritis and clinical endometritis as significant factors. In conclusion, supplementation of RPM had no beneficial effect on reproductive performance in this study farm compared with an untreated control group.