【作者】 郭孝；

【导师】 介晓磊；

【作者基本信息】 河南农业大学 ， 作物营养生理， 2010， 博士

【摘要】 硒和钴是动植物重要的微量元素,不但对牧草的产量和品质有显著的影响,而且也是畜禽生产中必需的重要营养元素,对动物生长发育及畜产品品质有重要影响。黄河中下游牧草生产基地和绿色奶业示范带多在黄河滩区及黄河故道,土壤多属砂质瘠薄型,硒钴等微量元素缺乏的问题尤其突出,一定程度地影响到当地的草畜生产,也影响到草畜产品的质量和安全性。2006～2009年,在河南省黄河滩区及沿岸地区,进行了苜蓿微量元素田间试验和动物饲养试验,研究硒、钴肥料土壤基施后通过在土壤-牧草-饲料-动物链(Soil-Pasture-Feed -Animal Chain,SPFAC)中的传导,对土壤肥力、牧草生长、饲草营养水平、动物饲料转化效率等的影响,进而探讨硒、钴在合理基施的情况下,通过SPFAC,达到既提高草畜生产水平、又能生产出营养全面且富硒钴的动物产品,实现土壤、牧草、饲料、动物等多级增效的目的,对保证优质牧草生产和动物食品安全具有重要理论意义和实际应用价值。研究结果如下:1.硒、钴施用对土壤的培肥效果单施硒肥能够促进0～20 cm土层中根系根瘤菌的生长,提高土壤碱解氮含量,对速效磷和速效钾的含量影响不显著;单施钴肥对0～20 cm土层中碱解氮、速效磷、速效钾以及有机质含量影响均不显著;硒钴配施不但能够提高0～20 cm土层中碱解氮和有机质含量,而且还提高速效钾含量,其中,硒和钴施用量分别在765 g/hm~2和1548 g/hm~2的情况下,碱解氮、速效钾和有机质含量分别提高了8.9 %、7.2 %和7.1 %。2.硒、钴施用对苜蓿生长、产量和质量的影响硒、钴的单施和合理配施均能在不同程度上促进苜蓿生长,提高苜蓿饲草产量,改善饲草营养水平以及增加饲草中Se、Co、Mo、Cu、B、Fe、Mn、Zn等元素的含量和积累量。(1)对苜蓿生长和产量的影响硒、钴单施和配合基施能够提高苜蓿硝酸还原酶(NR)的活性和氮代谢水平,而且能提高现蕾到开花期苜蓿叶片叶绿素含量和净光合能力,提高苜蓿的单位叶面积生产干物质的速率,有利于苜蓿的花前青干草生产和果实发育,当硒、钴配合基施,用量分别在570 g/hm~2和762 g/hm~2情况下,增产效果显著,青干草可增产8.06 %,果实千粒重可提高12.85 %。(2)对苜蓿的抗病性的影响硒、钴配合基施对开花-结实期紫花苜蓿的锈病、普通叶斑病、夏季黑茎病的发生有明显的抑制作用。当硒(765 g/hm~2)和钴(762 g/hm~2、1548 g/hm~2)分别配合基施下,表现出良好的防病效果,生长季节内锈病的发病率可分别降低24.7 %和31.6 %,叶斑病的发病率可分别降低22.7 %和25.2 %,苜蓿夏季黑茎病的发病率可分别降低19.0 %和25.2 %。另外,硒、钴配施对预防根腐病也有一定效果,当硒和钴用量分别在570 g/hm~2和1548 g/hm~2配合基施下,发病率可平均降低19.8 %,其中在结荚-成熟期防病效果最佳。(3)对苜蓿常规营养成分的影响当硒、钴配合基施,用量分别在765 g/hm~2和762 g/hm~2情况下,能显著提高苜蓿青干草的粗蛋白和粗脂肪含量,对粗纤维和无氮浸出物影响不显著,饲用价值得到了提高。其它硒、钴配施组合能显著地提高牧草中粗纤维含量,降低粗脂肪含量,对粗蛋白质和无氮浸出物含量影响不显著。(4)对苜蓿中硒钴含量的影响施用硒或钴肥料均能相应地提高苜蓿青干草中硒或钴含量;在供试施肥量范围内,硒施用量与苜蓿青干草中硒的积累量呈显著正相关关系,而施用钴量超过一定量后,苜蓿青干草中钴的含量维持相对稳定。虽然单施硒对草中钴积累量影响不大,但硒钴混合肥料可显著提高牧草钴的积累量,肥料中硒量越高草中钴的积累量越多。硒钴的合理配施还能显著提高苜蓿对硒钴的利用率,提高从肥料无机硒向牧草有机硒的转化率,从而增强牧草中硒的有效性和安全性。硒和钴施用量分别在765 g/hm~2和762 g/hm~2的情况下,其配合施用有效地提高苜蓿青干草硒的含量,比对照高1097.52 %,比单施硒高69.39 %;硒和钴施用量分别在765 g/hm~2和1548 g/hm~2的情况下,其混合肥料对提高苜蓿青干草的钴含量效果最有效,比对照高144.44 %,比单施钴高27.02 %。(5)对苜蓿饲草中Mo、Cu、B、Fe、Mn、Zn等6种微量元素含量的影响硒钴混合肥料能显著提高苜蓿青干草中Mo、Cu、B、Fe、Mn、Zn等6种微量元素含量,其中Mo的提高幅度最大,为142.34 %～476.20 %、其次为Fe、Mn和Zn,分别提高了48.16 %～59.45 %、32.88 %～41.66 %和37.10 %～96.39 %。Cu和B的提高幅度最小,分别为13.43 %～37.33 %和14.60 %～39.67 %。当硒和钴用量分别在765 g/hm~2和762 g/hm~2配合基施下,6种微量元素的平均含量和积累量达到最佳水平。3.硒、钴通过SPFAC对饲料营养价值的影响在荷斯坦奶牛、杜泊羊、新西兰大白兔和三黄鸡的饲料中,添加富硒、富钴和富硒钴苜蓿青干草或草粉(简称为富微牧草),不仅能提高畜禽日粮中Se和Co的含量,而且也能提高日粮中Zn、Mo、B、Cu、Fe和Mn等微量元素含量。在供试的各个动物日粮中,添加富硒钴苜蓿青干草或草粉(当硒和钴用量分别在765 g/hm~2和762 g/hm~2配合基施下生产的)效果最理想,在以上动物日粮中富微牧草适宜添加量为5 %～15 %。另外,该文利用硒钴配合基施生产的富微牧草,进行了饲料化技术研究,制定了富微牧草在以上4种动物日粮中的配制技术。4.硒、钴通过SPFAC对动物生长、饲料利用及产品质量的影响采用隔离养殖法,研究了用富微牧草配制的高微饲料日粮对3.5岁荷斯坦奶牛、50日龄杜泊羊、40日龄新西兰大白兔,35日龄三黄鸡和6周龄Wister大白鼠等动物生长性能、饲料转化及产品质量的影响,并制定了具体的利用技术。(1)硒、钴通过SPFAC对动物生长和饲料利用的影响在荷斯坦奶牛、杜泊羊、新西兰大白兔和三黄鸡以及Wister大白鼠的饲料中适当添加富硒、富钴和富硒钴3种富微牧草均可促进动物生长和提高饲料饲料转化率。其中在三黄鸡的日粮中添加5 %的富钴和10 %的富硒钴苜蓿草粉后,雏鸡的日增重分别提高19.0 %和26.2 %,饲料转化率分别提高21.2 %和29.5%;在新西兰大白兔的日粮中添加10 %的富钴和富硒钴苜蓿草粉后,幼兔的日增重分别提高12.4 %和11.0 %,饲料转化率分别提高7.6 %和6.1 % ;在荷斯坦奶牛日粮中添加5 %的富硒苜蓿青干草后,饲料转化率可提高13.9 %;在杜泊羊的日粮中添加15 %的富硒和10 %的富硒钴苜蓿青干草后,饲料的转化率可分别提高28.3 %和27.7 %。另外,在Wister大白鼠的日粮中添加4 %和6 %的富硒苜蓿草粉,能在不同程度上提高大白鼠的胃蛋白酶的活力、减少饲料在胃内的残留率,提高小肠对饲料的推动力,有利于饲料的转化与利用,日均增重分别提高了14.9 %和12.7 %,饲料转化率分别提高8.5 %和9.0 %,并且安全无副作用。(2)硒、钴通过SPFAC对奶产品品质的影响在荷斯坦奶牛日粮中添加富硒苜蓿青干草会明显降低牛奶中乳脂和乳蛋白的含量,但对乳糖以及非脂固形物含量影响不大;添加富硒钴苜蓿青干草能显著地提高牛奶中乳脂的含量,提高幅度为22.2 %,但会显著降低牛奶中乳糖以及非脂固形物含量,对乳蛋白的含量影响不大。(3)硒、钴通过SPFAC对动物肉产品品质的影响在新西兰大白兔和三黄雏鸡的日粮中添加富微牧草青草(或草粉)对肉产品中蛋白质、脂肪和碳水化合物的含量影响不显著的,但能适当提高肉产品中Fe、Cu和Zn的含量,显著提高肉产品中Se的含量,肝脏对微量元素的富积效果好于其他部位。(4)硒、钴通过SPFAC对动物产品中硒积累量的影响在新西兰大白兔和三黄雏鸡及Wister大白鼠等动物日粮中适当添加富硒和富硒钴苜蓿草粉,能显著地提高这些动物产品中骨骼肌、肝脏、心脏和肾脏中硒的含量和积累量,在动物产品中肌肉中硒的积累量最多,肝脏的硒浓度最高,动物产品中硒的积累量与土壤施硒量以及牧草中硒的积累量3者之间呈显著的正相关性。由于动物对饲料中的硒有很强的富积能力,所以富微苜蓿草不适宜在日粮中连续添加,而应该根据动物生长特点和需要间隔利用,做到既经济又高效。本文通过研究硒钴在“土-草-饲-畜链”(SPFAC)传导中对草畜生长与营养的调控,分析二者在土-草-饲-畜系统的多级增益效应及相应技术,明确了“土-草-饲-畜”(SPFAC)中涉及牧草种植、饲料添加及动物养殖等环节的中硒、钴微量元素应用的关键技术与指标参数,建立了一套解决动物微量元素营养问题的技术途径,即通过在土壤基施硒、钴肥料,使矿物态硒钴富集到牧草体内转化为有机态,根据动物营养需要,把富集硒钴的牧草进行饲料化应用,生产出具有高附加值畜产品,体现了增产提质、食品安全、生态健全和物质良性循环的理念。更多还原

【Abstract】 Selenium(Se)and cobalt (Co) are two kinds of important essential trace elements to forage and animal production. In Henan Province, the fine grass and green milk production zones are mainly distributed along the Yellow river beach where soils are sandy and sterile with lower Se and Co contents. Deficiency of Se and Co in soils affects local forage and animal production level as well as the qualities and securities of fodder and animal products. This paper put forward a concept of nutrient flow in Soil-Pasture-Feed -Animal Chain(SPFAC), and conducted a seris of field trials and animal experiments from 2006 to 2009 in order to study the multiple effects of Se and Co on soil fertility, growth and nutrition of forage plant(alfalfa[Medicago sativa L.]), animal feed conversion efficiency, and feasible concrete measurements to enhance production levels of grass and animal products rich in Se,Co and other nutrients, furtherly, established a set of effective technical ways to solve trace element gaps of soil, forage plant and animal diets, i.e. by basal fertilization of Se and Co fertilizers in soil, inorganic Se and Co could be accumulated in alfalfa plants by root absorption and transformed into organic Se and Co mostly, the pasture rich in Se and Co could also be uesed as fodder to produce animal products with higher extra values.The results showed as following:1. The effects of Se and Co on soil fertility Se fertilization could promote the growth of root nodule of alfalfa in a depth of 0-20cm soil, and improve top soil structure and increase available N and organic matter significantly. Co fertilization had less effects on soil fertility mentioned above. Combined application Se and Co not only raised the contents of available N and organic matter significantly, but also enhanced content of available K. When applying rates of Se and Cobalt being 570 g/hm~2 and 1548 g/hm~2, contents of available N, available K and organic matter could raise by 8.9 %, 7.2 % and 7.1 %, respectively.2. The effects of Se and Co on the growth, yield and fodder quality of alfalfa Single or rational combined application Se and Co fertilization could promote the growth of alfalfa, raise forage yields,improve nutrition levels of fodders and add contents and accumulation volumes of trace elements (such as Se, Co, Mo, Cu, B, Fe, Mn and Zn) in alfalfa plant.(1)The effects of Se and Co on the growth, yield of alfalfa plant Rational basal single and combined application of Se and Co all could not only enforce nitrate reductase activities and nitrogen metabolitic levels, but also promote net photosythetic efficiency,decrease plant respiration loss, enhance production rate of dry matter as well as seed growth from ramification to florescence, and raise alfalfa hay production before florescence. When application rates of Se being 570 g/hm~2, 762 g/hm~2, Se-Co combined fertilizers had best application effects on forage production and grain development, alfalfa hay was increased by 8.06 %(P<0.05)and 1000-grain weight was increased by 12.85 %(P<0.05).(2)The effects of Se and Co on disease-resistance of alfalfa plant Se and Cobalt combined basal fertilizer had great disease prevention effects on rust、brown spot、summer black stem and appeared more obvious effects in flowering-ripening stage. Under combined basal fertilization when application rate of Se was 765 g/hm~2, that of Cobalt was 762 g/hm~2 1548 g/hm~2, respectively, rust, brown spot, summer black stem could be prevented effectively, and alfalfa rust could be decreased by 24.7 % and 31.6 %, respectively, brown spot could be decreased by 25.2 % and 22.7 %, respectively, summer black stem could be decreased by 25.2 % and 19.0 %, respectively. Furthermore, Se and Co combined basal fertilizer also had obvious preventing effects on root rot which could be decreased by 19.8 % and showed more obvious effects in pods formation-ripening stage when Se application rate being 57 g/hm~2 and Cobalt application rate being 1548 g/hm~2.(3)The effects of Se and Co on major nutrients of alfalfa hay Se and Co single and combined fertilization had significant effects on major nutrients of alfalfa hay. When application rates of Se being 765g/hm~2, 762 g/hm~2, Se and Co single and combined fertilization had optimal applied effects which enhanced the contents of crude protein (CP)and ether extract(EE), kept stabilities of crude fiber(CF) and nitrogen-free extract(NFE) and enhanced feed values of alfalfa hay. Other single and combined fertilizers could enhance the content of CF more significantly,decrease the content of EE, and had no significant effluence on the of CP and NFE.(4)The effects of Se and Co fertilization on the contents of Se and Co in alfalfa hay Alfalfa had stronger capacities to absorb,transfer and utilize Se and Co from soil to plant root. Single basal application of Se and Co could increase the contents of Se and Co of alfalfa hays (and more Se in soil,more Se in hays).Within all Se and Co single and combined fertilization,there were more significant correlation(P﹤0.01)between Se applied amount and Se accumulation amount of alfalfa hay. Co accumulation amount of alfalfa hay kept stable. When Co applied rate increased the certain level, if more Co was applied in soil, some surplus Co might be wasted. Rational combined application of Se and Co could raise utilization rate of Se and ratio of transfor from inorganic Se from fertilizers to organic Se in forage. Effectiveness and securement of Se were all enhanced obviously. When applied rates of Se being 765 g/hm~2 and 762 g/hm~2, Se and Co combined use can raise Se accumulation amount effectively by 1097.52 % and 69.39 % in comparation with the control and Se single use. When applied rates of Se being 765 g/hm~2 and 1548 g/hm~2, Se and Co combined application can raise Co accumulation amount effectively by 144.44 % and 27.02 % in comparation with the control and Co single fertilization.(5)The effects of Se and Co fertilization on the contents of Mo, Cu, B, Fe, Mn and Zn in alfalfa hay Se and Cobalt applied fertilizers could enhance the contents of Mo, Cu, B, Fe, Mn and Zn more significanly(P﹤0.05). Of all 6 kinds of trace elements, the contents of Mo had most significant increasing levels (142.3% -476.2 %), next to Fe, Mn and Zn ( 48.1%-59.4 %, 32.9%-41.7% and 37.1 %-96.4%, respectively), Cu and B had lower increasing levels (13.4 %-37.3 % and 14.6 %-39.7%, respectively). When application rates of Se and Co being 765g/hm~2and 762 g/hm~2, respectively. The contents and accumulation of 6 trace elements mentioned above can reach optimal levels.3. The effects of Se and Co on feed nutrition levels while transmitted through SPFAC Supplement of alfalfa dust (rich in Se and Co)can raise the contents of Se, Co, Zn, Mo, B, Cu, Fe and Mn of animal(Holstein cows, Dorper sheep, New-Zealand rabbits and San Huang chicken)diets.Alfafa dust rich in Se and Co(produced when combined application rates of Se and Co being 765 g/hm~2,1548g/hm~2 respectively)had optimal effects on animal production. When alfalfa dust (rich in Se and Co)were supplemented with 5 %-15 %,.animal production were more efficient and safe. Based on studies and analysis of feedlize techniques about alfalfa produced by Se and Co basal fertilization,feed rationing techniques of high trace elements were formulated in animals(milk cattle,dorper sheep,rabbit and chicken).4. The effects of Se and Co on growth , feed utilization level and product quality of animal production while transmitted through SPFAC Adopting separate feeding, the effects of diets supplemented with alfalfa hay or dust (rich in high trace elements) on growing performances, feed conversion level and animal product quality were studied in some animal production coorporation and bases, such as Henan Sino-Dutch Dairy Technology and Development Co., Ltd, Xinmi New-star Rabbit Raising Base and Zhongmou Dorper Sheep Extension Base, etc. According to the animal growing and producing performances, more effective feed techniques along with multiple benefits were formulated simultaneously, some key techniques and index parameter were definited clearly concerning with grass planting and animal raising in SPFAC.(1)The effects of Se and Co fertilization on animal growth and feed utilization while transmitted through SPFAC When supplemented with three kinds of alfalfa dusts(rich in Se,Co and Se+Co) in diets of animals(including 3.5-year-old Holstein Lactating cows, 50-day-old Dorper sheep, 40-day-old weaned New-Zealand rabbits, 35-day-old San Huang chicken and 6-week-old Wister rat), not only daily gain and total gain were raised ,but also feed conversion rate were enhanced significantly.Of all experimental animals,chicken had best feeding effects, average daily gain and feed conversion rate were raised by 26.2% and 29.5 %, respectively when supplemented with 10 % alfalfa dust rich in Se and Co. Next to rabbit, average daily gain and feed conversion rate were raised by 12.4 % and 7.6 % respectively when supplemented with 10 % alfalfa dust(rich in Co). and raised by 11.0 % and 6.1 % respectively when supplemented with 10 % alfalfa dust(rich in Se and Co). Feed conversion rate of milk cow was raised by 13.9 % when supplemented with 5 % alfalfa dust(rich in Se). Feed conversion rate of sheep was raised by 28.3 % and 27.7 %, respectively when supplemented with 15 % alfalfa dust(rich in Se). and 10% dust(rich in Se and Co).All diets could enhance pepsin activities, decrease gastric remains feed, increase intake rate of Wister rat in early stage and enhance feed conversion efficiency(8.5 %～9.0 %) without harmful side effects compared with common alfalfa dust when application rates of alfalfa dusts with high contents of Se being 4 % and 6 %.(2)The effects of Se and Co fertilization on the quality of milk quality while transmitted through SPFAC Although alfalfa hay (rich in Se) could enhance cows forage conversion efficiency,they affect milk qualities, fat and protein in milk were decreased by 5 %-10 %, Lactose and SNF kept relative stable. Alfalfa hay( rich in Se and Co) could enhance fat 22.15%, protein kept stable, Lactose and SNF were dicreased significantly.(3)The effects of Se and Co fertilization on the quality of animal products while transmitted through SPFAC Alfalfa dust( rich in Se and Co) had no significant effects on contents protein, fat and Carbohydrate on rabbit and chicken, contents of some trace elements ,such as Fe、Cu and Zn were raised to some extent, contents of Se was enhanced more significantly.(4)The effects of Se and Co fertilization on Se content of animal products while transmitted through SPFAC When additive contents of alfalfa meal (rich in Se and Co)account for 5% of ration, Se contents of animal products (rabbit , chicken and rat)could be enhanced significantly, there were more significant conrelation(P﹤0.01)among Se accumulation amount in animal products, Se accumulation amount in pasture and Se applied amount in soil .This paper analysed additional benefits and critical techniques of Se and Co utilization in SPFAC, aims of which was to not only secure application of trace elements in forage and animal production, but also realize their multiple benefits in SPFAC. The results have great theoritical meaning and pratical value for safe production of forage and animal food products, which also was vital important to set up standardization production regulations as well as promote animal husbandry industrialization.更多还原