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161.
四川农村养猪日粮及平衡饲养技术初探   总被引:1,自引:0,他引:1  
在四川养猪主产地的不同地理生态区选点,深入农户广泛开展农村养猪常用饲料及日粮调研,采集饲料样品92个,分析测定铁、铜、猛、锌、钴、碘和硒的含量,将四川农村养猪日粮总结划分为:(1)玉米、青料日粮;(2)甘薯、青料日粮;(3)玉米、小麦、青料日粮;(4)玉米、大麦、青料日粮。并对各日粮的营养含量作了概算和评定。在此基础上,提出适合四川农村养猪日粮的添加剂预混料和浓缩料配制建议以及浓缩料主要营养指标推荐值。依此,开展了4种日粮的6批44组347头肉猪的饲养试验。从中优选出一批饲料配方,已在11个地市的40余家厂试产,省内外广大农村养猪中应用,有效地促进了饲料工业和农村养猪生产的发展。研制的甘薯青料日粮及平衡饲养技术,已列专题在省内大面积推广应用。经济效益和社会效益十分显著。  相似文献   
162.
This study was conducted to investigate the effects of probiotic (Primalac), prebiotic (TechnoMos) and synbiotic (Primalac + TechnoMos) supplementation on performance, immune responses, intestinal morphology and bacterial populations of ileum in broilers. A total of 240 one‐day‐old broiler chicks were randomly divided into four treatment groups which included 60 birds. Control group did not receive any treatment. The chicks in the second, third and fourth groups were fed probiotic (0.9 g/kg), prebiotic (0.9 g/kg) and probiotic (0.9 g/kg) plus probiotic (0.9 g/kg; synbiotic), respectively, at entire period. Daily feed intake, daily weight gain and feed conversion ratio were evaluated. The birds were immunized by sheep red blood cell (SRBC) on days 12 and 29 of age and serum antibody titres were measured on days 28, 35 and 42. Newcastle vaccines administered on days 9, 18 and 27 to chicks and blood samples were collected on day 42. Intestinal morphometric assessment and enumeration of intestinal bacterial populations were performed on day 42. The results indicated that consumption of probiotic, prebiotic and synbiotic had no significant effect on daily feed intake, daily body weight gain, feed conversion ratio, carcass traits, intestinal morphology and bacterial populations of ileum (p > 0.05). Consumption of prebiotic increased total and IgM anti‐SRBC titres on days 28 and 42 and antibody titre against Newcastle virus disease on day 42 (p < 0.05). Synbiotic increased only total anti‐SRBC on day 28 (p < 0.05). It is concluded that consumption of prebiotic increased humoral immunity in broilers. Therefore, supplementation of diet with prebiotic for improvement of humoral immune responses is superior to synbiotic supplementation.  相似文献   
163.
Understanding the links between large scale spatial structuring of fish assemblages and shaping factors is essential to develop comprehensive ecosystem-based fisheries management. In this study, we investigated spatial patterns of bottom fish assemblages in the North Sea in relation to prevailing water masses in the region. We based our analysis on catch data from the German Small-Scale Bottom Trawl Survey conducted between 1987 and 2005 and used both ordination techniques and Mantel tests. Spatial variability of bottom fish assemblages was larger than inter-annual variability. Five significantly different bottom fish assemblages were associated with the following prevailing hydrographical regimes: i) the English Channel, ii) Continental Coastal, iii) central North Sea, iv) northern North Sea, and v) northern Atlantic water masses. Associations were generated by gradients in relative proportions of abundant species such as grey gurnard ( Eutrigla gurnardus ), dab ( Limanda limanda ), whiting ( Merlangius merlangus ), haddock ( Melanogrammus aeglefinus ) and Norway pout ( Trisopterus esmarki ). Taking into account large scale spatial structuring of catch data Mantel tests confirmed significant correlation between the fish assemblages and hydrographical variables. In summary, our results strongly support the hypotheses that hydrographical features such as water masses, fronts, and residual currents could shape bottom fish associations in the North Sea. Spatial demarcations of bottom fish assemblages indicated by this study can be used to support ecosystem-based fisheries management strategies.  相似文献   
164.
In this paper through digestive and metabolic experiments studied the voluntary intake and apparent digestibility of cottonseed hulls (kernel-contained CH,kernel-free CH) and cornstalk on sheep to evaluate the nutrition value and digestion characteristics of cottonseed hulls.12 of adult Xinjiang merino rams were selected and divided into two groups (n=6 each group),and on the basis of 300 g/(head·day) of mixed concentrate,fed with kernel-free CH by 400 (group 1) or 800 (group 2) g/(head·day) respectively,to estimate the digestibility of CH by difference method;As well,another 18 of adult Xinjiang merino rams were selected and divided into three groups (n=6 each group),and on the basis of 300 g/(head·day) of mixed concentrate,cafeteria feeding with kernel-contained CH (group 3),kernel-free CH (group 4) or ground cornstalks (group 5) respectively,to study the effects of three diets on the voluntary intake,digestion and metabolism of sheep.The results showed that the apparent digestibility of the DM,OM,CP,cellulose,hemicellulose and energy of kernel-free CH by sheep were 46.71%,47.37%,-53.40%,66.60%,62.48% and 42.59%,respectively.There were no significant differences in the intake of DM,OM,cellulose,hemicellulose,energy and Ca between kernel-contained CH and kernel-free CH groups (P> 0.05);Intake of CP and P in kernel-contained CH group were extremely significantly higher than that in kernel-free CH group (P< 0.01);Intake of lignin in kernel-contained CH group was extremely significantly lower than that in kernel-free CH group (P< 0.01).There were no significant differences in the apparent digestibility of DM,OM and energy between kernel-contained CH and kernel-free CH groups (P> 0.05).The apparent digestibility of cellulose and hemicellulose in kernel-free CH group were significantly and extremely significantly higher than that in kernel-contained CH group (P< 0.05;P< 0.01),respectively.The apparent digestibility of CP in kernel-contained CH group was extremely significantly higher than that in kernel-free CH group (P< 0.01).The apparent digestibility of DM,OM,CP,cellulose and energy in ground cornstalks group were extremely significantly higher than that in kernel-contained CH and kernel-free CH groups (P< 0.01),however,the apparent digestibility of Ca and P were lower than that in kernel-contained CH and kernel-free CH groups (P> 0.05).Intake and retention of nitrogen in kernel-contained CH group were extremely significantly higher than that in kernel-free CH group (P< 0.01);The was no significant difference in the retention of nitrogen between kernel-free diet group and cornstalk diet group (P> 0.05).It was concluded that CH was a kind of special forage with larger intake,higher digestibility on the fiber substances and energy,but with a serious obstruction on protein digestion;The nutritional value between kernel-free diet and cornstalk diet was almost equal,and with lower nitrogen digestibility on kernel-free diet.  相似文献   
165.
抗菌肽饲料添加剂对小鼠巨噬细胞吞噬功能的影响   总被引:3,自引:0,他引:3  
对试验小鼠饲喂1‰和3‰抗菌肽饲料添加剂,鸡红细胞吞噬试验检测小鼠腹腔巨噬细胞吞噬功能,研究抗菌肽饲料添加剂对小鼠免疫功能的影响.结果表明,抗菌肽饲料添加剂可以显著提高小鼠腹腔巨噬细胞吞噬鸡红细胞的吞噬率和吞噬指数,增强小鼠非特异性免疫功能.  相似文献   
166.
167.
陈福元 《广东饲料》2000,9(2):31-33
本文详细介绍了大型膨化饲料加工工艺、设备选择及其注意的问题,指出了膨化饲料的发展方向和需解决的问题。  相似文献   
168.
将星杂288鸡种蛋960枚随机分为4组,进行3周孵化试验,各组空气负氧离子浓度分别为200000、100000、50000和40个/cm3。再取孵出的雏鸡120只随机分为4组,进行6周饲养试验,所设负氧离子浓度分别为100000、50000、25000和30个/cm3。结果表明:(1)200000和100000个/cm3负氧离子有助于胚胎的生长发育,能提高种蛋的孵化率;(2)50000个/cm3负氧离子可降低雏鸡料肉比和死亡率,并能促进雏鸡的生长发育,改善雏鸡的某些血液生理生化指标;(3)25000个/cm3以上的负氧离子对孵化和育雏的空气环境有一定净化作用。  相似文献   
169.
170.
Abstract –  The native and non-native freshwater fish species richness as well as the proportion of native fish species to overall fish species were examined to test a hypothesis of a spatial linkage between the distributions of dams and non-native fishes based on survey data collected in rivers and streams in Hokkaido, Japan. Non-native fish species have steadily increased in Hokkaido since the mid 1970s, as indicated by the decreasing proportion of native fish species per fish survey. Non-native species richness was significantly higher in areas above dams (i.e., reservoirs and their inlet streams) compared to areas without dams. As a result, the proportion of native fish species was lower above dams. This proportion was lower in developed and agricultural areas compared with forest areas, although both native and non-native species richness were higher in areas with development and agriculture. Non-native cyprinids, catfish and snakehead occurred primarily in a particular river basin with the largest drainage area, the longest history of reclamation and highest human population in the island. Non-native salmonids on the other hand, occurred in forest areas at higher elevations and their occurrence was associated with the existence of dams. There was a spatial linkage between the distribution of dams and non-native species, although it was applicable only to salmonids. The management of dams and reservoirs needs a strategy to prevent further expansion of exotic salmonids such as rainbow and brown trout. These species can be a significant threat to native Japanese salmonids as a result of various biological mechanisms.  相似文献   
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