越冬期绵羊放牧对冬小麦生长及产量的影响

对黄土高原区冬小麦（Triticum aestivum）陇育220进行越冬期绵羊放牧,跟踪观测返青后放牧与未放牧小麦土壤水分、分蘖数、生长期株高和鲜重及收获期籽实产量等,探讨越冬放牧对小麦生长及产量的影响。结果表明,1）冬小麦陇育220越冬前青饲草鲜产量4.68 thm-2,干草产量为1.35 thm-2。2）越冬放牧过的小麦,返青时耕作层土壤水分含量提高1.13%;拔节时平均分蘖数5.5个株-1,比未放牧（4.6个株-1）提高19.6%。3）随着生育期的推进,越冬放牧过的小麦株高极显著降低3.5～5.3 cm（P＜0.01）,相应的株鲜重也有所减少,但未有显著变化（P＞0.05）。4）放牧后小麦成熟期平均株高76.5 cm,比未放牧（82.1 cm）显著（P＜0.05）降低5.6 cm,穗数减少24.3个m-2,但籽实产量仅减少2.5%,未对小麦生产构成显著影响。研究表明,越冬放牧在黄土高原冬小麦农区切实可行。     

小麦秸秆处理方式对绵羊生长性能、瘤胃发酵性能及经济效益的影响

文章旨在评估不同小麦秸秆处理方式对干物质体外降解动力学及绵羊生长性能和瘤胃发酵性能的影响.试验将平均初始体重为(51.26±0.07)kg的24头绵羊随机分为3组,每组4个重复,每个重复2头羊.3组绵羊每天采食体重1％的基础浓缩料,对照组自由采食未处理的小麦秸秆,处理组绵羊分别采食2.5％氨水处理的小麦秸秆和5×108...     

Effects of three short-term pasture allocation methods on milk production,methane emission and grazing behaviour by dairy cows

Two short-term grazing experiments were conducted with Norwegian Red cows. In Exp 1, 24 cows were randomly assigned to one of the following three pasture allocation methods (PAM): weekly pasture allowance (7RG), grazing 1/7 of 7RG each day (1SG), or grazing as 1SG but had access to grazed part of the paddock within one week (1FG). In Exp 2, 7RG was shortened to 5 days (5RG). We hypothesized that PAM will affect sward quality, quantity, intake and production differently. Pasture chemical composition changed with advancing grazing days but were not different between treatments. Pasture intake, milk yield, and methane emission were not affected by PAM. In Exp 1, 7RG cows spent less time on grazing, whereas in Exp 2, 1FG cows spent longer on grazing than others. Patterns observed in sward quality, and behavioural and physiological adaptations of cows to short-term changes in nutrient supply may explain the observed effects.     

不同处理方式的橄榄饼渣对肉羊生长性能、屠宰性能及屠体品质的影响

文章旨在研究肉羊日粮中添加不同方式处理的橄榄饼渣对生长性能、屠宰性能及屠体品质的影响。试验选择健康、平均体重为(29.5±2.2)kg的肉羊120只,随机分为4组,每组6个重复,每个重复5头羊。试验共设计4种全混合日粮,均以玉米-豆粕为主,各组日粮中分别添加15%的未处理、碱处理、青贮处理及制粒处理的橄榄饼渣,试验共开展70 d。结果显示:不同处理方式的橄榄饼渣显著影响干物质摄入量(P <0.05),与制粒处理组相比,饲喂未处理、碱处理和青贮处理橄榄饼渣的肉羊日采食量显著提高(P <0.05);制粒组较其他三组显著降低了肉羊的料重比(P <0.05)。不同处理橄榄饼渣显著影响肉羊空腹重(P <0.05)。橄榄饼渣的不同处理方式对肉羊胴体、胃、肝脏、心肺的相对重量均无显著影响(P> 0.05)。与制粒组相比,未处理、碱处理及青贮处理胴体脂肪相对重量显著提高(P <0.05),同时盆腔、肾脏和肠系膜脂肪相对重量显著低于制粒组(P <0.05)。制粒组显著降低了胴体脂肪与体脂的比例(P <0.05)。结论 :在本研究的试验条件下,与普通未处理的橄榄饼渣相比,碱处理或青贮处理对肉羊生长性能无显著影响。未处理、碱处理及青贮处理的橄榄饼渣在肉羊日粮中适宜的添加水平为15%。     

高山草原绵羊放牧生态及消化代谢系列研究Ⅱ.放牧绵羊排尿量收集方法的新改进--纸尿裤法

利用纸尿裤法和常规法对６只甘肃高山细细毛羊成年竭羊，分别在祁连山东段高山草原７、８、１０、１月牧草生长的青草期、黄草期、葳草期共四期排尿量收集对比试验研究。实验表明，纸尿裤法收集收牧绵羊排尿量是常规法的１．６５－１．９４倍，纸尿裤法全面优于常规法，该方法的应用可以使放羯羊排尿量计量更加客观准确。     

放牧干扰和年际间降水量变化对地木耳生长速度的影响

地木耳(Nostoc commune)是一种固氮蓝藻,其固氮活性是可逆的,在天然草地氮素循环中起着重要的作用。试验模拟了年际间降水量变化和放牧强度对地木耳生长的影响,以期为合理利用和管理天然草地提供依据。结果表明,适度放牧促进了地木耳的生长,其早期和后期生长速度分别是不放牧时的3倍和4倍,不放牧时生长最慢。降水量对地木耳后期生长速度与早期生长速度的影响呈相反的趋势,高降水量显著提高了早期生长速度,是最低降水量时的14倍;平均降水量显著提高了后期生长速度。适度放牧、高降水量时早期生长速度最快,适度放牧、平均降水量时后期生长速度最快。     

Performance and grazing behaviour of Churra Tensina sheep stocked under different management systems during lactation on Spanish mountain pastures

Thirty-six adult ewes rearing single male lambs were randomly allocated to three paddocks (n = 12) grazing permanent Pyrenean pastures in spring (0.5 ha/lot). Treatments were rationed grazing (Rat-Gr) in which lambs remained indoors and ewes grazed during 8 h/day (08:00–16:00 h) and were supplemented 0.5 kg/day of barley meal; continuously grazing ewes rearing non-supplemented lambs (Gr) and continuously grazing ewes rearing supplemented lambs in creep feeders at pasture (Gr + S). Grazing behaviour was registered at weekly intervals by direct observation during the outdoor time in Rat-Gr and from dawn to dusk in Gr and Gr + S.

Sward height of Rat-Gr became higher than the rest (P < 0.05), resulting in a greater dry matter and a lower crude protein content of this pasture (P < 0.05). Ewe live-weight, body condition score and lumbar fat thickness were similar across treatments (P > 0.05), while milk yield was higher in Gr + S (P < 0.05). Lambs from Rat-Gr and Gr + S presented a higher average daily gain than Gr treatment (P < 0.05). Grazing behaviour records showed that all treatments spent grazing similar percentages of daylight time at pasture (average 52%; P > 0.05). Ewes biting rate was greater in Gr (P < 0.05) and it was higher after noon in all treatments (P < 0.001). Gr and Gr + S showed an extended peak of grazing (min/h) in the evening. Lambs followed the grazing pattern of dams since 3 weeks old. It was concluded that in contrast with the traditional indoor system of managing production of light lambs both spring continuous grazing systems allowed producing Ternasco lambs (18–24 kg LW, younger than 90 days old). Lambs supplemented suckling their mothers and grazing until slaughter showed similar performance to those obtained in indoor system. Dietary supplementation of lambs at pasture did not impair ewes milk yield and grazing time but reduced their biting rate and the offspring grazing time.     

Effect of liveweight and condition score of ewes at mating,and shearing mid-pregnancy,on birthweights and growth rates of twin lambs to weaning

AIMS: To determine the effects of liveweight and condition score of ewes at mating, and shearing mid-pregnancy, on birthweights and growth rates of twin lambs from birth to the time of weaning, and; to determine whether any effect of condition score is independent of liveweight.

METHODS: Romney ewes (n=435) which conceived within a 17-day mating period and successfully gave birth to and reared twin lambs to weaning were used. Ewes were managed during pregnancy so that their total liveweight increased at a level equivalent to the expected growth of the conceptuses. Approximately half of the ewes were shorn 70 days after the mid-point of mating, and the remainder were left unshorn, at which time they had 6-months' wool growth. All lambs were weighed within 12 h of birth and again at weaning.

RESULTS: There was a significant linear relationship (R²=0.99) between mean group liveweight and condition score of ewes at mating (difference of 7.3 kg per 1.0 unit condition score). Liveweight of ewes at mating had small but significant (p<0.05) positive effects on both birthweights and growth rates of twin lambs to weaning. Ewes that had condition scores of 3.5–4.0 (scale 0–5) at mating gave birth to significantly (p<0.05) lighter lambs than ewes that had condition scores <3.5. The condition score of ewes at mating was positively associated with growth rates of lambs, although this effect was largely explained by variation in the liveweight of ewes at mating.

Twin lambs born to ewes shorn mid-pregnancy were significantly (p<0.05) heavier at birth (by 0.4 kg) and at weaning (p<0.05) than those born to unshorn ewes. The heavier weaning weights of lambs born to ewes shorn mid-pregnancy were due to a heavier birthweights rather than increased growth rate.

CONCLUSIONS: Liveweight and condition score of ewes at mating had small positive effects on growth rates to weaning of twin lambs. Shearing mid-pregnancy increased birthweights and weaning weights of twin lambs. To achieve high weaning weights of twin lambs, farmers should ensure ewes attain high liveweights and condition scores at mating and shear mid-pregnancy. It is speculated that the effects of liveweight and condition score of ewes at mating on weaning weights of twin lambs would be greater than those observed in the present study under conditions in which nutrition of the dam is below optimum.     

水果提取物对羔羊生长性能、抗氧化及肉品质的影响

本研究旨在研究日粮添加水果提取物对羔羊生长和屠宰性能、组织器官抗氧化及肉品质的影响.试验将60只体重接近的羔羊随机分为2组,每组6个重复,每个重复5只.在为期4周的饲养期间,对照组饲喂基础日粮,处理组饲喂基础日粮+150?mg/kg水果提取物.结果:粮添加150?mg/kg水果提取物对羔羊屠宰率、热胴体重、冷胴体重、内...     

天然放牧条件下性别对苏尼特羊肌肉组织中胆固醇、脂肪酸含量和血清生化指标的影响

试验旨在研究不同性别的苏尼特羊血清生化指标及肌肉组织中脂肪酸与胆固醇含量存在的差异.试验选择在天然草场放牧的8月龄羯羔、母羔各8只,禁食12h、禁水2h进行屠宰,测定背最长肌、臂三头肌、股二头肌、臀肌中的脂肪酸、胆固醇等指标.结果 显示,母羔血清中白蛋白(ALB)和钙(Ca)含量显著高于羯羔(P＜0.05),而碱性磷酸...     

葡萄渣对肉鸡生长性能、营养物质消化及肉质的影响

文章旨在探讨葡萄渣对肉鸡生长性能、营养物质表观消化率和肉品质的影响。将500只1日龄肉鸡随机分为4组,每组5个重复,每个重复25只鸡。日粮分为4个处理:对照组(基础日粮),处理1~3组在基础日粮中分别添加4、6和8g/kg葡萄渣。试验从1日龄开展到28日龄。结果显示,日粮添加葡萄渣对体增重无显著线性影响(P>0.05),但对1~7d和8~14d体增重的影响具有显著二次曲线效应(P<0.05),22~28d和1~28d体增重、采食量和饲料转化率均无显著影响(P>0.05)。除灰分表观消化率随葡萄渣添加水平的升高呈二次曲线趋势外(P=0.07),葡萄渣对其他养分表观消化率无显著影响(P>0.05)。葡萄渣添加水平对血清中葡萄糖、甘油三酯和高密度脂蛋白水平无显著影响(P>0.05),而总胆固醇和血清IgG水平表现为显著二次曲线效应(P<0.05)。随着葡萄渣添加水平的升高,肌肉储存0、5和10d后硫代巴比妥酸反应物值表现为显著线性降低(P<0.05),在储存5d和10d时呈二次曲线效应(P<0.05)。此外,葡萄渣也显著降低了肌肉的鲜红度,表现为显著线性和二次曲线效应(P<0.05)。综上所述,在肉鸡日粮中添加8g/kg的葡萄渣,在不影响肉鸡生长性能、营养物质消化率和胴体性状的前提下可有效降低血清胆固醇,改善肉鸡的肉质参数。     

大豆油和黄油对羔羊生长性能、养分消化率及屠宰品质的影响

文章旨在研究不同脂肪原料(大豆油和黄油)对羔羊生长性能、养分消化率及屠宰品质的影响。试验选择均重(18.5±1.70)kg的公羊24只,随机分为3组,每组4个重复,每个重复2只羊,对照组饲喂以大麦为主的基础日粮(不加脂肪),黄油组和大豆油组分别在大麦型日粮中添加3.2%的黄油、大豆油,试验开展9周。黄油和大豆油组较对照组显著提高了酸性洗涤纤维摄入量(P <0.05),同时粗脂肪摄入量也显著高于对照组(P <0.05)。与对照组相比,大豆油和黄油组显著提高了羔羊日增重和末重(P <0.05)。日粮添加脂肪较对照组显著提高了羔羊总增重(P <0.05)。大豆油和黄油组较对照组显著提高了粗脂肪表观消化率(P <0.05)。日粮添加脂肪显著提高了N的摄入量(P <0.05)。黄油组较对照组显著提高了热屠体和冷屠体重(P <0.05),大豆油和黄油组较对照组显著提高了肝脏和肾脏脂肪重量(P <0.05)。黄油组较大豆油组显著提高了最长肌重量(P <0.05),对照组和黄油组较大豆油组显著提高了腰肌系水力(P <0.05)。结论 :大麦型日粮中添加3.2%大豆油和黄油可以提高羔羊日增重、末重和屠体重,对养分消化率和胴体品质有一定改善。     

谷胱甘肽对肉羊生长性能、屠宰性能及肉品质的影响

选择东北细毛羊×德国肉用美利奴的杂交一代肉羊12只,分成对照组、试验Ⅰ组和Ⅱ组,每组4只,研究谷胱甘肽对肉羊生长性能、屠宰性能及肉品质的影响。试验期60 d。结果表明:与对照组相比,谷胱甘肽显著提高了肉羊的日增重(P<0.05),试验Ⅰ组、Ⅱ组分别提高了14.6%和11.4%;降低了肉羊的料重比(P<0.05),试验Ⅰ组、Ⅱ组分别降低了11.0%和8.1%。试验Ⅰ组的净肉率和GR值显著高于对照组(P<0.05),Ⅱ组的宰前活重显著高于对照组(P<0.05);试验Ⅰ组肉的剪切力显著低于对照组(P<0.05);试验Ⅰ组、Ⅱ组的滴水损失显著低于对照组(P<0.05),而熟肉率显著高于对照组(P<0.05),且两试验组间差异不显著(P>0.05);各试验组宰后45 min内肉的pH没有显著差异(P>0.05),但试验Ⅰ组24 h的pH极显著地高于其他2组(P<0.01)。     

霉菌毒素污染日粮对后备母猪生长性能、养分消化及血液指标的影响

文章旨在评估呕吐毒素污染的玉米对后备猪生长性能、养分消化及血液指标的影响.试验选择平均初始体重为(33.77±0.23)kg的二元后备猪320头,随机分为4组,每组4个重复,每个重复20头.对照组饲喂正常玉米～豆粕型日粮,处理组饲喂分别用100、200和300?g/kg呕吐毒素污染的玉米替代正常玉米配制日粮,试验共进行...     

补饲精料对乌珠穆沁羊生产性能、屠宰性能和肉品质的影响

试验旨在研究草颗粒和草颗粒补饲精料对乌珠穆沁羊生产性能、屠宰性能和肉品质的影响。选取20只6月龄体重为(28.83±0.19) kg乌珠穆沁羊,采用随机区组设计,随机分为2组,每组10只。设计2种日粮饲喂乌珠穆沁羊,分别为草颗粒(对照组)和草颗粒补饲精料(试验组)。结果表明:补饲精料未能显著影响羊的日增重(P>0.05),日增重分别为56.33和60.00 g。对照组和试验组的3项屠宰性能指标(宰前活重、胴体重、屠宰率)、6项化学成分指标(粗蛋白、粗脂肪、有机物、干物质、钙、磷)、6项肉品质指标(pH1、pH24、大理石纹、亮度、熟肉率、剪切力)、16项脂肪酸指标和15项氨基酸指标差异均不显著(P>0.05)。试验组羊4项屠宰性能指标(净肉重、净肉率、眼肌面积、GR值)、4项肉品质指标(红度、黄度、胆固醇、失水率)、6项脂肪酸指标(十三碳酸、肉豆蔻酸、珍珠酸、γ-亚麻酸、α-亚麻酸、花生酸)和3项氨基酸指标(异亮氨酸、酪氨酸、精氨酸)均显著高于对照组(P<0.05)。对照组7项主要脂肪酸(丁酸、月桂酸、肉豆蔻烯酸、十五碳酸、十五碳烯酸、棕榈酸、棕榈油酸、硬脂酸、油酸、n-6/n-3)、苏氨酸和谷氨酸显著高于试验组(P<0.05)。饲喂草颗粒补饲精料对乌珠穆沁羊生长性能影响不大;天然草地草颗粒饲喂能满足家畜营养需求,在促进乌珠穆沁羊生产性能、屠宰性能和肉品质方面具有重大潜力。     

酵母硒和酵母铬对羔羊生长性能、胴体品质、血液激素及代谢产物的影响

文章旨在研究日粮添加酵母硒和酵母铬对羔羊生长性能、胴体品质、血液相关指标的影响。试验选择平均体重为(26±4.75)kg的呼伦贝尔羔羊60只,随机分为6组,每组10只,每只羊作为1个重复。日粮采用2×3多因子设计,其中2个酵母硒水平(0和0.3 mg/kg,以硒计)和3个酵母铬水平(0、0.2和0.3 mg/kg,以铬计),试验共进行12周。随着酵母铬添加水平的升高,羔羊采食量显著线性升高(P <0.05)。酵母硒组羔羊末重、总增重和日增重随酵母铬添加水平的升高显著线性升高(P <0.05)。无酵母硒组随酵母铬添加水平的升高,血浆葡萄糖水平显著线性升高(P <0.05)。血浆甘油三酯和胰岛素水平随酵母铬添加水平的升高表现为显著二次曲线效应(P <0.05)。酵母硒组血浆甘油三酯和胰岛素水平随酵母铬添加水平的升高显著线性升高(P <0.05),而血浆尿酸含量显著线性下降(P <0.05)。无酵母硒组随酵母铬添加水平的升高,眼肌面积和胴体蛋白沉积量显著线性升高(P <0.05)。酵母硒组添加酵母铬对羔羊胴体相关指标均具有显著影响(P <0.05),其中屠体重、热胴体和冷胴体重、眼肌面积和能量沉积量随酵母铬添加水平表现为显著二次曲线效应(P <0.05),而脂肪含量和脂肪沉积量显著线性降低(P <0.05)。综上所述,硒酵母与铬酵母联合使用可以提高羔羊生产性能和改善胴体组成,改善血液激素和代谢产物,从而提高羊肉品质。     

中草药提取物对热应激肉牛生长性能、养分消化、瘤胃发酵及肉品质的影响

文章旨在研究中草药提取物对热应激肉牛生长性能、养分消化、瘤胃发酵和肉品质的影响.试验将48头体重无统计学差异的肉牛随机分为两组,每组24头,每组12个重复,每个重复2头牛.对照组与处理组肉牛分别饲喂全混合日粮+0和120 mg/kg中草药提取物,试验为期8周,饲养环境温度为(32±1.5)℃.结果:与对照组相比,中草药...     

Effects of formulating growing pig diet with increasing levels of wheat‐corn distillers dried grains with solubles on digestible nutrient basis on growth performance and nutrient digestibility

Formulating swine diets containing fibrous coproducts based on net energy (NE) and standardized ileal digestible amino acid (SID AA) values is recommended for optimizing pig performance. However, the effects of applying this approach to diets with increasing dietary levels of wheat‐corn‐derived distillers dried grains with soluble (wcDDGS) on pig performance have not been evaluated. Thus, 48 pigs with an average body weight [BW] of 25.5 kg were used to determine the effects of increasing wcDDGS (1:1 wheat to corn ratio) content in grower diets on performance and apparent total tract digestibility (ATTD) of energy and nutrients. Pigs were housed in pens of either 2 barrows or gilts balanced for BW and fed 4 diets within sex for 42 days. Diets were a nutrient adequate corn–barley–soybean meal‐based diet with 0%, 10%, 20% and 30% wcDDGS, and were similar in calculated NE and SID AA values. Acid insoluble ash was used as the indigestible marker. Final BW and overall average daily gain (ADG) linearly decreased (p < 0.05) and feed efficiency tended to decrease (p = 0.07) with increased dietary wcDDGS. Overall average daily feed intake was not affected (p > 0.10) by dietary treatment. The ATTD of dry matter and energy linearly decreased (p < 0.01), whereas the ATTD of neutral detergent fibre linearly increased (p < 0.01) with increasing dietary level of wcDDGS. Increasing dietary wcDDGS content did not affect (p > 0.10) ATTD of Ca and P. In conclusion, increasing dietary wcDDGS content reduced growth performance and ATTD of energy in growing pigs. Thus, the risks of high dietary wcDGGS content may not be completely alleviated by formulating growing pig diets on the basis of NE and SID AA systems.     

CLA发酵豆粕对羔羊生长性能、胴体性能和肉品质的影响

选择120只健康、体重(11.77±0.70)kg的黄淮白山羊公羔,随机分为4组,每组6个重复,每个重复5只。对照组饲喂基础日粮,试验Ⅰ、Ⅱ、Ⅲ组分别用2.5%、5.0%和7.5%CLA发酵豆粕等量替代基础日粮中普通豆粕,预饲期为10 d,正式试验期为30 d。结果表明:CLA发酵豆粕对黄淮白山羊公羔的生长性能均无显著影响(P>0.05);试验Ⅲ组的胴体骨重显著高于对照组和试验Ⅰ组(P<0.05),试验Ⅲ组的骨肉比极显著高于对照组和试验Ⅰ组(P<0.01),其他胴体性能无显著差异(P>0.05);CLA发酵豆粕对黄淮白山羊公羔的肉品质而及羔羊肌肉的化学指标均无显著影响(P>0.05)。     

日粮纤维水平对猪生长性能、养分消化和磷代谢的影响

文章旨在探讨日粮添加不同水平的纤维素对猪生长性能、养分表观消化率和磷损失的影响.试验将平均初始体重为(48.68±0.29)kg的320头生长猪随机分为4组(T1～T4),每组4个重复,每个重复20头.各组饲喂不同纤维素水平的无磷日粮,纤维素水平分别为0、30、60和90?g/kg,试验共开展21?d.结果:不同纤维日...