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101.
<正>饲料是畜牧业赖以发展的物质基础,饲料成本约占整个畜禽养殖成本的60%—70%。三十多年来,我国饲料工业取得了巨大成就,走过了许多发达国家五十年甚至上百年才走完的历程,实现了世界第一大饲料生产国的飞跃,2018年我国饲料总产量已达2.28亿吨[1]。我国饲料工业的快速发展,有力地推动了我国畜牧经济的发展,改善了人们的物质生活水平。近年来,我国畜禽养殖业规模化、集约化发展迅速,饲料企业的规模和产品结构也发生了较大变化。一些小型饲料企业逐渐被淘汰,规模生产企业占绝对主导地位,配合饲料的比例越来越高,  相似文献   
102.
This research was conducted for the purpose of determining the effects of bat guano on plant nutrient contents in the soil and in lettuce (Lactuca sativa L.) during the spring of both 2014 and 2015 with three replications according to randomized blocks experiment design. Bat guano was applied to the soil in two different forms; According to the results organic matter, P, Cu and Mn amounts in the soil were found to be statistically significant and increased compared to the control. Likewise, in the application of bat guano dust, organic matter, P and Mn amounts in the soil were found to be statistically significant and increased compared to the control. In lettuce, N, K, Mg, Fe, Cu, Zn and Mn amounts in the application of bat guano powder and K, Ca, Mg, Fe, Zn and Mn amounts in the application of bat guano dust were found to be statistically significant.  相似文献   
103.
Changes in quality parameters including pH, water activity, texture, and lipid oxidation were studied in pasteurized chum salmon (Oncorhynchus keta) ikura samples packaged using two films with different oxygen transmission rates (OTR) (40 and 62 cm3·m?2·day?1; F-40 and F-62), during 60 days storage at 4°C. No significant differences in pH and water activity (aw) were observed between ikura packaged using two different films with different OTR (P > 0.05). However, compared to the first day of study, water activity decreased significantly in ikura (P < 0.05). Ikura thiobarbituric reactive substance (TBARS) in the pouches significantly increased during the storage at 4°C (P < 0.05). Both pouches showed similar trends in TBARS until day 29, while after day 29, ikura packaged in F-62 (OTR = 62 cm3·m?2·day?1) showed a significant increase in TBARS compared to F-40 with less OTR (P < 0.05). The texture of ikura became softer compared to the first day; however, no significant difference was observed between the ikura samples in two pouches (P < 0.05). The quality changes of ikura measured during storage indicate that packaging ikura in a lower OTR film would provide greater quality retention than one with higher OTR.  相似文献   
104.
A feeding experiment was conducted to study the response of rainbow trout juveniles fed different levels of lupin meal in diets for rainbow trout juveniles. Very limited information is available on the relationship between dietary lupin meal in rainbow trout health status. Therefore, this study aimed to determine the effects of lupin meal inclusion levels (0%, 15%, 30%, 45%, and 60%) on growth performance and health status of rainbow trout juveniles. The experimental diets (LM0, LM15, LM30, LM45, and LM60) were formulated iso‐nitrogenous (41% crude protein) and iso‐calorific (18% crude lipid). The fish were fed twice a day. As a result, the best growth performance was observed in fish fed with LM15 and LM30 diets. No significant differences were detected among experimental groups in terms of body compositions. The haematological values showed significantly (p < 0.05) lower heamatocrit and mean cellular volume (MCV) in the group of LM60 compared with the other groups. For the other haematological parameters such as haemoglobin, red blood cell and mean cellular haemoglobin studied in the present study no significant differences were observed (p < 0.05). The lupin meal included groups showed significant reduction in total protein (TPROT), triglyceride (TROG), cholesterol (CHOL), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) compared with the control group (p < 0.05). The inclusion of lupin meal did not cause any changes in glucose (GLU), glutamic oxaloacetic transaminase (GOT), and glutamic pyruvic transaminase (GPT) between the treatment groups (p < 0.05). In conclusion, lupin meal might be used in rainbow trout diets up to 30% without any malnutrition effect on growth performance, haemotological and serum biochemical parameters.  相似文献   
105.

Objective

To describe an ultrasound-guided approach for venous and arterial vascular access and catheterization in anesthetized adult Yorkshire cross-bred pigs.

Study design

Prospective experimental study.

Animals

Ten adult female Yorkshire cross-bred pigs, weighing 78.4 ± 5.6 kg (mean ± standard deviation).

Methods

Using ultrasound guidance and the Seldinger technique, a 7 Fr, 20 cm triple-lumen central venous catheter was placed in the external jugular vein and an 18 gauge, 16 cm catheter was placed in the femoral artery. The success rate of catheterization and the incidence of catheter patency over 24 hours of general anesthesia were recorded.

Results

Catheterization of the external jugular vein was successful in 10 out of 10 pigs and catheterization of the femoral artery was successful in eight out of 10 pigs. A surgical dissection technique on the femoral artery was performed in two pigs. Venous and arterial catheter patency was maintained in all pigs over the 24 hour study period.

Conclusions and clinical relevance

Ultrasound guidance resulted in success rates of 100% for catheterization of the external jugular vein and 80% for catheterization of the femoral artery in anesthetized adult Yorkshire cross-bred pigs. This technique is a noninvasive, easily performed alternative to surgical exposure of the vessels in large pigs undergoing surgical instrumentation for biomedical device testing.  相似文献   
106.
San Martin, B., Cornejo, J., Lapierre, L., Iragüen, D., Pérez, F., Hidalgo, H., Andre, F. Withdrawal time of four pharmaceutical formulations of enrofloxacin in poultry according to different maximum residues limits. J. vet. Pharmacol. Therap. 33 , 246–251. To ensure delivery of safe animal products to consumers, the withdrawal time (WDT) of drugs must be respected. Property differences among pharmaceutical formulations, for the same drugs, can lead to differences in the WDTs estimation. The WDTs of four commercial formulations of enrofloxacin (ENRO) in broiler chickens, considering MRLs established by different countries, were studied. Two hundred‐thirty‐four broiler chicks were allotted among four groups; the formulations were orally administered daily with 10 mg/kg bw. After treatment, six chickens of each group and two controls were slaughtered daily until day 9 post‐treatment. Samples of muscle and liver were collected, and analyzed using HPLC‐MS‐MS. The WDTs among formulations of ENRO showed differences of 24 and 48 h. Based on the European Community and Chile MRLs of 100 μg/kg (muscle) and 200 μg/kg (liver), the WDTs did not exceed 5 days. When Japan MRL was considered (10 μg/kg,), the WDTs increased up to 8 days. These results indicate that for WDTs determination, the differences among pharmaceutical formulations of a drug must be considered as well as the MRLs.  相似文献   
107.
108.
Several species of red algae (Rhodophyta) from the coastal regions of Madagascar have been investigated for their natural products. The most abundant compound was cholesterol (5) in combination with a series of oxidized congeners. The brominated indoles 1–3 along with the sesquiterpene debilone (4) have been isolated from Laurencia complanata. For the first time, debilone (4) has been obtained from a marine plant. From the methanol extract of Calloseris sp., we have achieved the second isolation of the unusual A-ring contracted steroids (−)-2-ethoxycarbonyl-2β-hydroxy-A-nor-cholest-5-en-4-one (9) and phorbasterone B (10). The crude extracts of Laurencia complanata exhibited antimicrobial activity against Bacillus cereus, Staphylococcus aureus, Streptococcus pneumoniae, and Candida albicans.  相似文献   
109.
旨在对比研究马链球菌马亚种(Streptococcus equisubsp.equi,S.equi)3种不同抗原蛋白——分选酶A(sortase A,SrtA)、M蛋白(SeM)及IgG结合蛋白(EAG)的免疫原性及免疫保护效果,本研究以表达并纯化的Sr-tA、SeM及EAG 3种蛋白单独及联合免疫小鼠,免疫后检测了血...  相似文献   
110.
以30份国内外红皮花生资源为材料,对其10个品质性状进行相关性分析、主成分分析和聚类分析.结果表明:30份材料的蔗糖含量变异系数为25.74%,粗脂肪、花生酸和总糖变异系数分别为3.42%、4.40%和2.05%.相关性分析表明:粗脂肪与蔗糖呈极显著负相关,蛋白质与脂肪酸呈极显著负相关.主成分分析表明:10个品质性状简...  相似文献   
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