DDGS对肥育猪生长性能和血清生化指标的影响

为研究玉米-豆粕型饲粮中使用DDGS对肥育猪生长性能和血清生化指标的影响,选择120头体重约60kg的杜×长×大三元杂肥育猪随机分为5组,对照组饲喂玉米-豆粕型基础饲粮,试验I组、II组、III组DDGS使用量分别8%,16%,24%,试验IV组添加24%DDGS+复合酶(添加量:160mg/kg),进行为期45d的饲养试验。结果表明,与对照组比较,各试验组平均日增重分别降低7.44%,13.69%,28.04%和19.76%,其中试验II、III和IV组差异显著(P0.05);各试验组平均日采食量分别降低3.53%,6.01%,15.90%和8.48%,其中试验III和IV组差异显著(P0.05);各试验组料重比分别提高4.14%,8.88%,17.76%和13.61%,其中试验III和IV组差异显著(P0.05)。45d各组间血清总胆固醇、甘油三酯、血清磷、谷草转氨酶和谷丙转氨酶含量均无显著差异(P0.05)。饲粮中DDGS使用量为8%和16%对肥育猪生长性能无显著影响。     

不同来源淀粉对断奶仔猪氮代谢的影响

选择平均体重(8.80±1.0)kg、(28±2)d三元杂交(杜×长×大)断奶仔猪4头,进行为期21 d的消化试验和4×4拉丁方代谢试验,研究不同来源淀粉对氮代谢的影响。结果表明:糯米日粮有利于增加尿氮排泄量,总氮利用率比玉米日粮低(P<0.05)。糯米日粮降低仔猪增重主要受饲料利用效率降低影响。抗性淀粉日粮增加粪氮排泄(P<0.05),显著减少尿氮排泄(P<0.05),显著降低氮表观消化率(P<0.05)。     

LJAMCE对猪生长性能与生化指标的影响

摘 要 杜×长×大三元杂交肥育猪48头被随机分成三组,即对照组、试验1组和试验2组。三组猪试验处理如下：在基础饲粮中加黄霉素20mg/kg后,喂对照组猪;在基础饲粮中加0.15﹪金银花-黄芪复合提取物（LJAMCE）后,喂试验1组猪;在基础饲粮中加0.3﹪LJAMCE后,喂试验2组猪。饲养试验期为40d。饲养试验结果如下： ①试验1、2组猪的日增重均在不同程度上快于对照组猪,分别提高了20.4﹪（P＜0.05）和10.0﹪（P＞0.05）;②LJAMCE可提高饲料转化率,分别比对照组提高9.8﹪（P＞0.05）和5.2﹪（P＞0.05）。③饲粮中加0.15﹪LJAMCE对GPT活性、IgG、TG、vLDL等血液生化指标都有不同程度的积极作用;④LJAMCE在饲粮中适宜添加量为0.15﹪。 关键词 LJAMCE;生长性能;生化指标;育肥猪     

日粮不同赖氨酸水平对生长猪养分表观消化率、血清氨基酸含量和生化指标的影响

研究日粮中不同赖氨酸水平对生长猪养分表观消化率、血清氨基酸含量和血清生化指标的影响.试验采用全收粪法进行,选用12头始重约为20 kg的长×大二元杂交阉公猪,按体重随机分为3个处理组,处理Ⅰ饲喂含赖氨酸0.65%的基础日粮,处理Ⅱ和处理Ⅲ在基础日粮中添加晶体赖氨酸盐酸盐,使赖氨酸含量分别为0.95%和1.25%,试验期为10 d.结果表明,该试验条件下,适宜的赖氨酸含量(处理Ⅱ组)使猪日粮养分表观消化率达到较好的水平,而降低赖氮酸含量(处理Ⅰ组)会使日粮能量、干物质、粗蛋白和磷的表观消化率显著降低(P<0.05);而降低或升高日粮赖氨酸水平会显著影响血清中丝氨酸(Ser)、谷氨酸(Clu)、苏氨酸(Thr)、半胱氨酸(Cys)、酪氨酸(Tyr)和赖氨酸(Lys)的含量(P<0.05或P<0.01);同时,处理Ⅰ组血清中血清尿素氮(BUN)和血清总蛋白(TP)的含量分别显著高于和低于处理Ⅱ组和处理Ⅲ组(P<0.05),但日粮不同赖氨酸水平对血清中血糖(GLU)、甘油三酯(TG)的含量无显著影响(P>0.05).结果表明,在本试验条件下,20～35 kg生长猪日粮总赖氨酸建议需要量为0.95%.     

不同淀粉来源日粮对断奶仔母猪内脏组织蛋白质合成的影响

为了研究玉米、糙米、糯米和抗性淀粉等不同谷物淀粉对断奶仔猪内脏组织蛋白质合成率(FSR)的影响,以16头28日龄断奶的杜×长×大三元杂交仔母猪(体重(8.0±0.4)kg)为试验对象,一次性大剂量腹腔注射L-[2H5]苯丙氨酸溶液后,测定了内脏组织蛋白质周转状况。结果表明,来源于玉米日粮组的淀粉促进了断奶仔猪内脏组织蛋白质的合成,其FSR高于糙米和抗性淀粉日粮组,显著高于糯米日粮组,且十二指肠、空肠、回肠、结肠、胰脏和肝脏的FSR分别比糯米日粮组高85.87%,47.47%,37.29%,56.29%,43.55%和17.63%。可见,日粮淀粉来源不同,对仔猪内脏组织FSR的影响也不同。     

低蛋白质日粮对麻羽肉鸡生长性能、血清生化指标及粪氮含量的影响

本试验旨在研究低蛋白质日粮对麻羽肉鸡生长性能、血清生化指标及粪氮含量的影响。选取1日龄麻羽肉鸡225只,随机分为3组,每组5个重复,每个重复15只。分1~28日龄和29~56日龄2个阶段饲养,每个阶段配制3种日粮。对照组1~28日龄和29~56日龄分别饲喂粗蛋白质水平为21%和18%的日粮;试验Ⅰ组、试验Ⅱ组饲喂在对照组日粮基础上分别降低1、2个百分点的低蛋白质日粮,并通过添加合成氨基酸将日粮的必需氨基酸水平与对照组保持一致,试验期56天。结果表明：（1）1~28日龄、29~56日龄及1~56日龄肉鸡平均日采食量、平均日增重及料重比各组间均无显著差异(P＞0.05)。（2）28、56日龄血清总蛋白、尿素氮、尿酸含量各组间均无显著差异(P＞0.05)。（3）1~28日龄及29~56日龄试验Ⅰ组、试验Ⅱ组粪氮含量分别比对照组下降了5.98%、11.23%及8.09%、11.88%,差异均显著(P＜0.05)。由此可见,在满足氨基酸需要的前提下,降低日粮粗蛋白质1~2个百分点对麻羽肉鸡生长性能、血清生化指标无显著影响,但可显著降低粪氮含量。     

半乳甘露寡糖取代金霉素对育肥猪血清生化指标和激素水平的影响

将48头育肥猪(杜×长×大)随机分为2组,每组3个重复,在同一玉米-豆粕型基础日粮中分别添加0.1%半乳甘露寡糖(GMOS)和50 mg/kg金霉素(CTC),进行了46 d的对比试验。饲养试验结束后,从2个处理的每个重复分别选择1头阉公猪空腹采血10 mL,以检测这2种添加剂对其血清生化指标和激素水平的影响。     

新型酿酒酵母培养物对育肥猪生产性能、肌肉品质和肠道微生物的影响

本试验旨在研究日粮中新型酿酒酵母培养物(YCB)添加量对育肥猪生产性能、肌肉品质和肠道微生物的影响。选取440头初始体重为(61.49±0.36 kg)的健康三元杂交（杜×长×大）育肥猪,随机分为4组,基础日粮中未添加酿酒酵母培养物为试验Ⅰ组,添加2.5%传统酵母培养物(YCA)为试验Ⅱ组、添加2.5%新型酵母培养物(YCB)为试验Ⅲ组、添加5% YCB为试验Ⅳ组,试验期60天。结果表明：（1）基础日粮中添加YCA和YCB对育肥猪的平均日增重、饲料利用率均有所改善,其中试验Ⅳ组料重比最低,但差异不显著。（2）与试验Ⅰ组相比,试验Ⅱ、Ⅲ和Ⅳ组可显著降低肌肉滴水损失率和剪切力(P<0.05),其中试验Ⅳ组最低;与试验Ⅰ组相比,试验Ⅱ、Ⅲ和Ⅳ组肌内脂肪分别提高2.8%、6.7%和6.9%,但差异不显著;通过透射电镜发现,试验Ⅱ和Ⅳ组肌原纤维蛋白微量降解,试验Ⅰ组和Ⅲ组肌原纤维蛋白明显降解。（3）试验Ⅲ组和Ⅳ组粪便中瘤胃球菌属、颤螺菌属和粪球菌属等纤维分解菌属的丰度上升,显著增强育肥猪的脂质代谢、碳水化合物代谢、淀粉和蔗糖代谢(P<0.05),改善胆汁酸代谢和脂质代谢。综上可知,在育肥猪生产上添加YCB可以改善育肥猪的生产性能和肌肉品质,通过调节肠道微生物进而影响机体代谢,其生产中适宜添加量为5%。     

千里光超微粉对仔猪生长性能、部分血清生化指标的影响

为研究日粮中添加千里光超微粉对仔猪生长性能和部分血清生化指标的影响,选取体重为10 kg左右的杜×长×大三元杂交仔猪90头,按随机区组设计、公母各半的原则,将仔猪分成5个处理组,每个处理3个重复,每个重复6头仔猪。Ⅰ组饲喂基础日粮,Ⅱ组饲喂添加75 mg/kg金霉素和20 mg/kg硫酸粘杆菌素的日粮,Ⅲ、Ⅳ、Ⅴ组分别饲喂添加0.4%、0.8%、1.2%千里光超微粉的日粮。试验期为30天。结果发现,添加千里光超微粉能提高仔猪平均日增重和平均日采食量,降低料肉比,其中添加0.8%的千里光超微粉能显著提高仔猪的平均日增重(P＜0.05)、显著降低料肉比(P＜0.05),且与Ⅱ组的效果相当(P＞0.05);添加千里光超微粉能在一定程度上提高血清GLU、TG、T3、T4、IGF-I含量,降低血清BUN含量,其中添加0.8%的千里光超微粉能显著提高血清T3、IGF-I的含量(P＜0.05),显著降低BUN含量(P＜0.05)。表明仔猪日粮中添加0.8%的千里光超微粉能显著提高仔猪平均日增重和血清T3、IGF-I含量,显著降低料肉比和血清BUN含量,改善仔猪的生长性能。     

复方中草药添加剂对仔猪饲料代谢动力学的研究

通过消化与饲养实验,研究中草药添加剂对仔猪的促生长作用机理。消化实验采用外源指示剂法,按照4×4完全拉丁方设计,用8头平均体重为9.65±1.26kg的35日龄杜长大三元杂交公猪进行了35天试验(其中预试期7天);饲养实验利用40日龄胎次相近、平均初重为10.19±1.86kg的断奶杜长大三元杂交仔猪5窝36头按照单因子随机区组设计,在经过28天的试验后结束时进行了空腹血液指标分析测定。试验得出的主要结论有:①中草药添加剂显著提高了断奶仔猪对饲料粗蛋白(CP)和酸性洗涤纤维(ADF)的表观消化率(P<0.05);中草药1组在提高饲料CP与ADF消化方面分别比喹乙醇组高14.68%、38%;②中草药添加剂显著提高了仔猪血液血小板数(PLT)(P<0.05);③中草药添加剂组比喹乙醇组显著降低了仔猪血液谷丙转氨酶(ALT)的浓度(P<0.05),提高了血液葡萄糖(Glu)的浓度(P<0.05),中草药添加剂的安全性需要重新评估。④中草药添加剂提高了血液总蛋白(TP)、白蛋白(Alb)、血清尿素氮(BUN)、谷草转氨酶(AST)、乳酸脱氢酶(LDH)和肌酸激酶(CK)的含量,差异不显著(P>0.05)。结果:复方中草药添加剂通过提高仔猪对饲料粗蛋白质与酸性洗涤纤维的表观消化率、增强蛋白质与葡萄糖的吸收、加快糖类在体内的代谢,达到对仔猪促生长作用的效果;中草药添加剂在猪饲料中的安全使用需要进一步深入研究。     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

Relation between wheat-rye crossability and seed set of common wheat after pollination with other species in the Hordeae

Summary Cultivars of common wheat (Triticum aestivum L. em. Thell.) of high wheat-rye (Secale cereale L.) crossability set more seed with pollen of other related species than did wheats of low wheat-rye crossability. This was found to be true for pollen parents from the genera Triticum, Aegilops, Secale, Agropyron and Elymus.     

Breeding apomictic bahiagrass (Paspalum notatum Flügge) with improved turf traits

The development of a turf‐type bahiagrass could have a remarkable impact on the billion‐dollar turf industry in the south‐eastern United States. The goals of this study were to (i) select bahiagrass genotypes with improved turf attributes and (ii) determine the reproductive mode and seed fertility of selected genotypes. The population included mutants, wild types, hybrids and standard cultivars evaluated at two locations for two years. Morphological variation was observed and clonal repeatability (H²) ranged from 0.27 to 0.90. Flowering was extremely reduced in some mutants, which also exhibited dark green colour, finer texture and reduced canopy height. Cytoembryological observations revealed that diploids reproduced sexually and tetraploids by obligate or facultative apomixis. Genotypes with superior seed fertility were identified, while others were comparable to the standard cultivars. While mutant plants exhibited great morphological variation, the random mutations did not affect their reproductive mode, validating the use of mutagenesis in apomictic species. The high H² indicated that selection for improved turf attributes could be successfully performed with the advantage of clonal seed propagation.     

Inheritance of fruit colour in a wild Russian red raspberry seedling

Summary A new gene, i, from a self-incompatible wild Russian Rubus idaeus seedling is described. The gene i interacts with the fruit colour gene T, Tii plants having apricot instead of red fruits, and spines, leaves and stems pigmented to varying degrees. A deficit of apricot-fruited seedlings in progenies segregating for i could be explained by linkage between i and the self-incompatibility S locus with a crossover value of approximately 26.7%.Segregations for spine colour in crosses and backcrosses of the Russian seedling with two green-spined (ttII) raspberries selected for their yellow fruit colour, showed that both the latter carried the spine colour intensifier gene P. This suggests that earlier authors were incorrect in attributing the apricot fruit colour developed by some tt plants to a pleiotropic effect of P.     

Flag Leaf Senescence, as Evaluated by Numerical Image Analysis, and its Relationship with Yield under Drought in Durum Wheat

Senescence was evaluated at different stages of the grain‐filling period in eight durum wheat varieties using numerical image analysis (NIA). The varieties were grown under early, severe drought conditions on the high plains of Sétif in Algeria. After flowering, three different irrigation treatments were applied. Treatment effect was small, while a genotypic effect was noted for most of the senescence parameters. Senescence correlated to biomass, while the maximal rate of senescence, V_smax, correlated to thousand‐kernel weight. The potential of the method of numerical image analysis for monitoring flag leaf senescence, detecting genotypic variability and selecting genotypes with delayed senescence is discussed.     

Mechanisms and diversity of resistance to sorghum shoot fly,Atherigona soccata

Sorghum shoot fly, Atherigona soccata, is one of the important pests of postrainy season sorghums. Of the 90 sorghum genotypes evaluated for resistance to this pest, RHRB 12, ICSV 713, 25026, 93046 and 25027, IS 33844‐5, Giddi Maldandi and RVRT 3 exhibited resistance in postrainy season, while ICSB 463, Phule Anuradha, RHRB 19, Parbhani Moti, ICSV 705, PS 35805, IS 5480, 5622, 17726, 18368 and 34722, RVRT 1, ICSR 93031 and Dagidi Solapur showed resistance in rainy season, suggesting season‐specific expression of resistance to A. soccata. ICSB 461, ICSB 463, Phule Yasodha, M 35‐1, ICSV 700, 711, 25010, 25019 and 93089, IS 18662, Phule Vasudha, IS 18551 and 33844‐5 and Barsizoot had fewer deadhearts than plants with eggs across seasons, suggesting antibiosis as one of the resistance mechanism. Five genotypes exhibited resistance with high grain yield across seasons. Correlation, path and stepwise regression analyses indicated that leaf glossiness, seedling vigour, trichome density, oviposition and leaf sheath pigmentation were associated with the expression of resistance/susceptibility to shoot fly, and these can be used as marker traits to select and develop shoot fly‐resistant sorghums.     

Cowpea (Vigna unguiculata): Genetics,genomics and breeding

Cowpea, Vigna unguiculata (L.), is an important grain legume grown in the tropics where it constitutes a valuable source of protein in the diets of millions of people. Some abiotic and biotic stresses adversely affect its productivity. A review of the genetics, genomics and breeding of cowpea is presented in this article. Cowpea breeding programmes have studied intensively qualitative and quantitative genetics of the crop to better enhance its improvement. A number of initiatives including Tropical Legumes projects have contributed to the development of cowpea genomic resources. Recent progress in the development of consensus genetic map containing 37,372 SNPs mapped to 3,280 bins will strengthen cowpea trait discovery pipeline. Several informative markers associated with quantitative trait loci (QTL) related to desirable attributes of cowpea were generated. Cowpea genetic improvement activities aim at the development of drought tolerant, phosphorus use efficient, bacterial blight and virus resistant lines through exploiting available genetic resources as well as deployment of modern breeding tools that will enhance genetic gain when grown by sub‐Saharan Africa farmers.     

Screening for resistance to take-all in wheat,triticale and wheat-triticale hybrid lines

Summary Fifteen triticale and wheat-triticale hybrid lines were evaluated for resistance to the take-all fungus Gaeumannomyces graminis var. tritici and compared with five wheat and two rye lines in inoculated field and pot trials. The triticale and wheat-triticale hybrid lines varied in rye chromosome number and degree of resistance expressed. One line, Venus with seven pairs of rye chromosomes consistently showed levels of resistance intermediate between wheat and rye. A trend was observed where increasing rye chromosome content led to greater resistance but exceptions showed that variation within triticales could not be ascribed to rye chromosome content alone.     

Reaction of tritordeum to Fusarium culmorum and Septoria nodorum

Summary Hordeum chilense is a wild barley extensively used in wide crosses in the Triticeae. It could be a valuable source of resistance to Fusarium culmorum and Septoria nodorum. Some H. chilense x Triticum spp. amphiploids, named tritordeums, were more resistant than the parental wheat line to these diseases, others were not. Average contents of ergosterol and deoxynivalenol (DON) suggested that resistance to colonization by Fusarium was the highest for Hordeum chilense, followed by tritordeum and wheat in decreasing order. In particular, the H. chilense genotypes H7 and H17 enhanced the wheat resistance to F. culmorum in its tritordeum offsprings. Resistance to S. nodorum in tritordeum was not associated with tall plant height. There is sufficient genetic variation for resistance to F. culmorum and S. nodorum among tritordeum to allow the breeding of lines combining short straw and resistance to both diseases.