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151.
LI Xiao-meng LI Qiu-feng CAO Yu-feng YU Chun-qi LI Jian-guo GAO Yan-xia 《中国畜牧兽医》2015,42(7):1705-1710
This experiment was conducted to study the effect of different dietary nutrition levels on fattening effect of Holstein bulls.48 4-month-old Holstein bulls with an average body weight of 128 kg were allocated into two groups,group Ⅰ was fed a low nutrition level diet,group Ⅱ was fed a high nutrition level diet.Each group had 24 Holstein bulls.The pre-test period lasted for 7 days and the trial period lasted for 245 days.The results showed that compared with group Ⅰ,the ADG in group Ⅱ was significantly increased by 6.36% (P<0.01),while the F/G in group Ⅱ was decreased by 6.55%.With the increasing of dietary nutrition levels,the apparent digestibility of CP,EE,NDF,ADF,Ca and P were rising,but there was no significant differences between two groups (P>0.05).Compared with group Ⅰ,the serum GLU,AST,ALT and GH contents in group Ⅱ were increased by 12.52%,12.85%,9.68% and 13.24% (P<0.05),respectively,while the serum BUN content in group Ⅱ was decreased by 10.98% (P<0.05).Compared with group Ⅰ,the feeding profits of group Ⅱ increased by 1.37 yuan/(head·day),the total economic benefit of group Ⅱ increased by 335.65 yuan/head.In conclusion,the improvement of dietary nutrition levels could improve the fattening performance and the economic benefit of Holstein bulls. 相似文献
152.
The objective of this study was to evaluate of the growth performance, serum biochemical indices, liver antioxidant parameters and ability of anti-infection with Aeromonas hydrophila by adding the fermented Chinese medicine by Bacillus Subtilis to the carp fish feed, and to find out the appropriate supplemental level of fermented Chinese medicine in diets. Carp fingerling with an initial body weight of (35±0.5) g were set up to 6 experimental diets supplemented with 0 (control group), 0.1‰, 0.5‰, 1‰, 2‰ and 3‰ fermented Chinese medicine for 56 days, respectively. Each group had 30 fish and set up 3 repetitions. After the feeding trail,the fish were challenged with Aeromonas hydrophila to calculate the relative percentage survival (RPS).The results showed as follows:Supplementing fermented traditional Chinese medicine by Bacillus subtilis, the weight gain rate (WGR), specific growth rate (SGR), condition factor (CF), the activities of lysozyme (LSZ), complement 3 (C3),total protein (TP),total anti-oxidation capacity (T-AOC),total superoxide dismutase (T-SOD) and catalase (CAT) in serum of common carp were enhanced at different degrees, while the feed coefficient (FCR)and malondialdehyde (MDA) in serum were declined at different degrees.When the fermented Chinese medicine supplemental levels were 2‰ and 3‰,the effects were significant (P<0.05)(except for C3, ALP and Cr).The experimental results of the virulence of common carp infected with pathogen Aeromonas hydrophila showed that,the fermented herbal could obviously improve the ability of anti-infection, the immune protective rate of the group with 2‰, 3‰ doses of the fermented Chinese medicine could reach 77.23% and 74.63%, respectively. From what had been discussed above, the group with 2‰ and 3‰ doses of the fermented Chinese medicine had significant effect on the growth performance, serum biochemical indices, liver antioxidant parameters and Aeromonas hydrophila anti-infection ability. Considering the cost of adding fermented Chinese medicine, the recommendations for the best additive quantity was 2‰. 相似文献
153.
白唇鹿血清生化指标测定 总被引:4,自引:1,他引:3
测定了35头青海白唇鹿的19项血清生化指标。结果为Na^2+138.1±5.84mmol/L,K^+5.75±0.73mmol/L,Ca^2+2.42±0.20/L,P2.33±.38mmol/,Cl^-,102.2±6.03mmol/L,总蛋白87.50±6.17g/L白蛋白59.18±6.96g/L球蛋白28.34±5.26g/L,A/G,2.19±0.59,血清蛋白质组分(%)A67.57± 相似文献
154.
家兔乳酸脱氢酶等生化指标的测定及其与生产力关系的研究 总被引:2,自引:0,他引:2
对8个品种家兔的血清Ca、P、K、Na、乳酸脱氢酶和血清蛋白质含量的测定并经LSR检验表明,各品种家兔之间乳酸脱氢酶及其同工酶含量不同,其生产性能与A、B亚基含量相关,含A亚基越丰富,其生长速度越快;各品种间血清总蛋白、白蛋白、球蛋白含量、白/球比值及β-球蛋白含量均存在不同差异,生长发育快的家兔的血清总蛋白、球蛋白、β-球蛋白含量较高,白蛋白含量及白/球比值较低 相似文献
155.
岩羊血液生化遗传多态性的研究 总被引:3,自引:0,他引:3
采用聚丙烯酰胺凝胶电泳和火焰光度法对青海省19只岩羊13个血液生化遗传基因座的多态性特征进行了研究。结果发现:①ES2、ES3、ES4、S-LDH、S-ALP和TF6个基因座存在多态性,而KE、HB、AMY1、AMY2、AMY3、ES1、RBC-LDH和RBC-ALP7个基因座呈单态;②被检岩羊的多态性基因座比例为46.2%,表明岩羊的血液生化遗传基因座有颇大的遗传变异性。 相似文献
156.
157.
Relationships between landcover proportion and indices of landscape spatial pattern 总被引:10,自引:0,他引:10
Recent studies have related percolation theory and critical phenomena to the spatial pattern of landscapes. We generated simulated
landscapes of forest and non-forest landcover to investigate the relationship between the proportion of forest (Pi) and indices of patch spatial pattern. One set of landscapes was generated by randomly assigning each pixel independently
of other pixels, and a second set was generated by randomly assigning rectilinear clumps of pixels. Indices of spatial pattern
were calculated and plotted against Pi. The random-clump landscapes were also compared with real agricultural landscapes.
The results support the use of percolation models as neutral models in landscape ecology, and the performance of the indices
studied with these neutral models can be used to help interpret those indices calculated for real landscapes. 相似文献
158.
甜玉米新种质生化成分的分析 总被引:3,自引:0,他引:3
以我国自己转育成的甜玉米新种南材料,研究甜玉米的生化成分,优势率和遗传控制,研究结果表明,(1)甜玉米新质各种生化成分与原始基因型接近,营养价值高,食味品质好;(2)甜玉米品质性状优势率以负(向)优势为主,明显不同生长势性状的优势率;(3)普甜,甜脆,超甜玉米籽粒外观性状和糖分含量均受其各自的一对隐性基因控制。 相似文献
159.
通过1986~1990年间80多个田间小麦肥效试验,研究了石家庄地区小麦生产进入高产阶段后不同肥力土壤上小麦肥效曲线方程、高产经济施肥指标。结果表明,不同肥力麦田的小麦高产经济施肥指标为:高肥力麦田亩施N11.1~13.8kg,P_2O_510.7~13.9kg,中肥力麦田亩施N12.6~15.2kg,P_2O_59.8~12.1kg;低肥力麦田亩施N13.3~15.5kg,P_2O_59.1~11.7kg。还研究了小麦目标产量施肥法所需的三个施肥参数:(1)小麦百公斤产量养分吸收量,空白区平均为:N2.32kg,P_2O_51.05kg,K_2O2.72kg;施肥区平均为:N2.82kg,P_2_51.03kg,K_2O_3.15kg。(2)土壤速效磷和碱解氮的校正系数(C_P、C_N)分别为:C_P=0.41+4.01/P,C_N=0.28+0.035P。(3)氮、磷肥利用率(Z_N、Z_P)分别为:Z_N(%)=42.1-0.35P,Z_P(%)=27.6-1.20P(P为土壤速效磷含量)。 相似文献
160.
Indices are needed in habitat conservation and restoration to provide repeatable measures relevant to conservation goals. A monitoring and research program was established at Nachusa Grasslands in north-central Illinois (USA) to assess progress in tallgrass prairie restoration and reconstruction efforts and evaluate the effectiveness of indices used to measure community-level properties related to vegetation integrity. Indices selected for comparison included standard diversity measures (e.g., Shannon-Weiner Index, Evenness, Species Richness) and indices developed specifically to estimate vegetation integrity. These latter indices included two unweighted diversity indices, the Species Richness Index and Native Richness Index, and two indices weighted by characteristics of species composition, the Floristic Quality Index (FQI) and its component Mean Coefficient of Conservatism (Mean C). A coefficient of conservatism (CC) is an integer ranging from 0 to 10 assigned a priori to each taxon in a regional flora that estimates the fidelity of a species to natural areas (non-native and most ruderal species are assigned 0 or low values, respectively; species known primarily from natural areas are assigned higher values). All indices compared in this study were calculated using vegetation data collected from equal-sized sampling grids stratified across seven prairie units. The units included remnants and plantings representing a wide range of habitat quality. The FQI and Mean C explained the most variation among sites and were most effective at distinguishing recognized qualitative differences indicating they can be more informative than traditional species-diversity measures in assessing floristic integrity within community types. The FQI and Mean C are applicable to both quantitative ecological monitoring and plotless survey methods. 相似文献