利用可消化干物质评定牧草饲用价值

牧草的饲用价值,应包括它的产量和质量两方面。那种单纯追求产量而不考虑质量的概念是不全面的。因此,必须树立一个既能反映产量又能反映质量的综合概念来评定,笔者认为这个综合概念可采用测定可消化干物质和可消化粗蛋白质量的方法。可消化干物质是饲用价值的重要部分。     

反刍动物秸秆饲料的补饲技术

<正>反刍动物秸秆饲料的补饲技术是秸秆饲料化工程技术中营养管理技术的重要内容,是挖掘反刍动物自身营养潜力、高效利用农作物秸秆的重要调控技术之一。1补饲的原则1使秸秆中廉价可利用的碳水化合物的采食量最大,也就是秸秆基础日粮的采食量最大。2添加非蛋白氮源(尿素或氨),使秸秆基础日粮的可发酵氮含量达到可消化干物质的3%。3补饲相当于日粮干物质10%~20%的青绿饲料,     

补饲预防羔羊食土癖

青海省湖东种羊场及周围地区的青海细毛羔羊在断奶后,发生以食土为主的异嗜,多次食土后羔羊出现发育不良、消瘦、腹泻以至死亡,给该地区的养羊业造成一定的经济损失。为此,在１９９５年９月和１９９６年９月,先后对湖东种羊场地区的患羔进行了常量元素钠、钾、钙、磷、氯和微量元素钴、锌以及维生素Ｂ１２营养状况的调查。根据调查结果,拟定给羔羊补饲食盐及含钴、锌的混合食盐,观察效果,以达到预防食土癖的目的。１　材料与方法１．１　供试羊　湖东种羊场地区尚未食土的青海细毛初断奶羔羊８１只（母羔５１只,公羔３０只）,登记…     

反刍动物秸秆基础日粮补饲苜蓿的组合效应

本文综述了反刍动物秸秆基础日粮补饲苜蓿的组合效应，并对该类饲料组合效应的产生机理进行了归纳，指出经作者改进的卢德勋（2003）提出的组合效应综合评定指数（MFAEI）可对饲料间组合效应进行整体量化．指导反刍动物秸秆基础日粮的补饲。     

反刍动物秸秆基础日粮补饲苜蓿的组合效应

本文综述了反刍动物秸秆基础日粮补饲苜蓿的组合效应，并对其机理进行分析。     

AM生物菌剂发酵小麦秸秆料对山羊补饲的效果

试验采用6月龄子午岭黑山羊40只，随机分为试验组和对照组，两组每天混群放牧8h，除试验组归牧后补饲AM发酵秸秆料外，其它条件均一致，试验进行60d。试验结果：小麦草秸经AM发酵后，粗蛋白提高43．41％，粗纤维降低34．42％；试验组日增重219g，比对照组88g提高150％，差异极显著（P＜0．01）；屠宰性能、经济效益也明显优于对照组。     

奶牛怎样补饲脂肪

脂肪喂量要适当 奶牛日粮中脂肪的含量最多不能超过日粮干物质的7％。在正常情况下。奶牛基础日粮本身就含有3％左右的脂肪，因此。补充量一般为3％～4％。即1天1头奶牛应补充0．45～1．36kg脂肪。如果日粮中脂肪的添加量超过7％，就会降低瘤胃微生物的活性，影响对粗纤维的消化，导致奶牛食欲降低，使干物质采食量下降。产奶量降低。     

承德绒山羊补饲试验报告

在承德市丰宁和宽城两处各选择绒山羊60只,随机分成2组,试验组和对照组,每组30只。坝上试验组每天补饲配合料0.3kg,宽城试验组每天补饲配合料0.25kg,对照组按原饲养方式进行。结果表明,坝上绒山羊补饲0.3kg全价料,能量达到2.547MJ,粗蛋白达到27.08g,能够保证羊绒生长需要和怀孕需要。宽城绒山羊补饲0.25kg全价料,能量达到2.093MJ,粗蛋白达到22.34g,能够保证绒山羊绒生长、维持需要和怀孕需要,且绒产量都比对照组有明显提高。     

夏南横交牛犊牛补饲试验研究报告

本试验针对夏南横交牛犊生长发育特点,采取提前补饲精料的办法,研究适时补饲对其日增重、断奶重的影响,探索提高其断奶体重的方法。从存栏的初生牛犊中,随机选择了37头夏南横交牛,分为试验组30头,对照组7头,试验期180d,试验结果：试验组平均初生重41．43kg,平均目增重0．88kg,6月龄时平均体重达199．57kg(实称重);对照组平均初生重42kg,平均日增重0．73kg,6月龄时平均体重达173．43kg。试验组与对照组平均日增重经t检验差异极显著。     

肉羊补饲尿素的方法

在肉羊的育肥过程中农民朋友常常添加尿素以加快出栏,提高经济效益.但添加多少却参差不一,经过多年的实践证明羊的尿素补饲量以占饲草、饲料干物质的2%为宜.也可按体重的0.02%～0.05%喂给,即每10千克体重可喂2～5克.6月龄以前的羊不宜喂尿素.     

应用纤维素酶评定秸秆饲料的消化率及其影响因素的研究

应用纤维素酶+胃蛋白酶法评定了6种秸秆饲料在绵羊体内的消化率。试验结果表明:酶解的消化率(X)与体内干物质消化率(DMD),有机物消化率(OMD),和能量消化率(ED)之间有显著的相关性,求出估测方程为: 体内:DMD(％)=6.95+0.75X r=0.89(P<0.01),RSD=1.81 OMD(％)=9.39+0.80X r=0.76(P<0.05),RSD=3.25 ED(％)=0.92X-1.75 r=0.78(P<0.05).RSD=3.54 酶解法具有良好的重演性和稳定性(变异系数平均4.66％)。     

Milk production responses to pre- and postcalving dry matter intake in grazing dairy cows

Sixty-eight multiparous grazing dairy cows were randomly allocated to two precalving pasture allowances to achieve differential dry matter intakes (DMI) for 29 ± 7.7 d precalving (Low or High DMI; 4.8 or 11.9 kg DM). At calving, cows within each precalving treatment were randomly allocated to one of two levels of feeding (Low or High DMI; 8.6 or 13.5 kg DM) for 35 d postcalving in a completely randomized design and a 2 × 2 factorial arrangement of treatments. Following treatments all cows grazed together and were fed pasture and pasture silage. Daily milk yields were recorded, and fat, protein and lactose concentrations determined weekly for 15 weeks. Blood was sampled weekly pre- and postcalving and analysed for indicators of energy status, growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Body condition score (BCS) at calving was reduced by precalving restriction (P < 0.001; 2.8 and 3.0 for precalving Low and High treatment groups, respectively). Precalving restriction reduced milk fat production by 8.4% during the first 5 weeks postcalving, but differences were not significant subsequently. Postcalving feed restriction reduced yield of fat corrected milk (FCM), fat and protein by 23, 21 and 28%, respectively, during the first 5 weeks postcalving. Decreased (P < 0.05) yields of FCM, fat and protein (11, 10 and 9%, respectively) were also evident for 10 weeks after the feed restriction finished. There was a tendency (P < 0.1) for a precalving × postcalving DMI interaction in milk protein yield during the first 5 weeks of lactation with no effect of precalving level of feeding in cows that were restricted postcalving. The plasma concentrations of non-esterified fatty acids (NEFA), β-hydroxybutyrate (BOH) and GH were elevated in restricted cows precalving, and IGF-1 concentration was reduced. Plasma NEFA and BOH concentrations were elevated postcalving in restricted cows, but no effect of postcalving DMI on GH or IGF-1 concentration was evident. Results suggest that under grazing systems milk production responses to precalving DMI are small, but energy restrictions in early lactations result in significant carryover effects in milk production.     

添加酶制剂改善"双低"菜籽粕矿物质、干物质和能量代谢的研究

本试验研究了"双低"菜籽粕中添加植酸酶、木聚糖酶、β-葡聚糖酶、果胶酶、纤维素酶等非淀粉多糖酶对"双低"菜籽粕中矿物质和干物质、能量代谢率的影响,以及各种酶制剂的适宜添加水平.试验结果表明添加植酸酶、木聚糖酶、β-葡聚糖酶、果胶酶可以改善"双低"菜籽粕中钙、总磷、植酸磷、铁、锌、锰以及干物质和能量的代谢率,并且随着酶制剂的添加量增加,"双低"菜籽粕中干物质和矿物质的代谢率得到改善的幅度也越大.     

Determination of Pasture Dry Matter Intake Rates in Different Seasons and Their Application in Grazing Management

Eight mature horses weighing 576 ± 32 kg (mean ± SD) were used to compare differences in pasture dry matter (DM) intake rate in October (period 1), February (period 2), and May (period 3). Horses were randomly assigned to a pair of adjacent 5 m × 5 m grazing cells containing nontoxic, endophyte-infected tall fescue. Horses had access to each cell for 4 hours. Pasture DM intake rate was estimated over the entire 8-hour period by measuring the pre- and postgrazing herbage mass within each cell and was expressed as kg DM/100 kg body weight (BW)/hr. Mean 8-hour DM intake rate in period 1 (0.17 ± 0.01 kg DM/100 kg BW/hr) was greater (P < .001) than for period 2 (0.09 ± 0.01 kg DM/100 kg BW/hr) and period 3 (0.11 ± 0.01 kg DM/100 kg BW/hr), but it was not different (P = .274) between periods 2 and 3. A second experiment using the same eight horses was conducted immediately after the first experiment, within each season, to determine whether the DM intake rates derived from the first experiment could be used along with estimates of maintenance digestible energy (DE) requirements and pasture DE concentrations to predict the amount of grazing time required for a horse to consume only its maintenance DE requirement and maintain zero BW change over a 6-week period. Grazing time necessary to maintain zero BW change was accurately predicted for period 1 only.     

不同处理的小麦秸在绵羊体内的消化率及其对瘤胃液pH 值、NH-N 浓度的影响

从整体消化和瘤胃消化的角度出发,研究了复合处理(尿素 石灰)对小麦秸营养价值的影响。结果表明:①复合处理优于尿素处理;②复合处理可使小麦秸的干物质消化率(DM-D)、有机物消化率(OMD)、能量消化率(ED)和中性洗涤纤维消化率(NDFD)分别提高10.8%,21.4%,23.4%,43.8%。     

The Effect of Hay Net Design on Rate of Forage Consumption When Feeding Adult Horses

Modern horse management systems tend to limit a horse's opportunity to forage. The objective of this experiment was to investigate the effect of hay net design on the rate of forage consumption when feeding horses. Eight adult horses were fed in individual stalls in a replicated Latin square design, with two horses per treatment per week. Horses were fed hay off the stall floor (control), or from one of three hay nets: large (15.2 cm openings), medium (4.4 cm openings), and small (3.2 cm openings). Horses had access to hay for two 4-hour periods each day. When horses could not consume all forage from the medium and small hay nets in 4 hours, a second study using a crossover design gave horses an unlimited amount of time to feed from the hay nets. Stopwatches were used to calculate time to consumption and dry matter intake rates (DMIR). Mean time to consumption was 3.1 and 3.4 hours for the control and large hay net, respectively, in study 1, and 5.1 and 6.5 hours for the medium and small hay nets, respectively, in study 2. Mean DMIR during the 4-hour feeding period were 1.5, 1.3, 1.1, and 0.9 kg/hr for the control, large, medium, and small hay nets, respectively; all treatments were different (P < .0001). These results demonstrate that hay nets were effective at decreasing the rate of forage consumption when feeding adult horses. Long-term studies are warranted to determine if horses will adapt to feeding from hay nets.     

断奶日龄对仔猪Et玫瑰花环形成率和T淋巴细胞转化率的影响

选取15窝杜洛克×长白×约克夏三元杂交初生仔猪 ,按14、21、28、35日龄断奶和不断奶随机分为5组(14E、21E、28E、35E、C) ,每组3窝 ,研究断奶及不同断奶日龄对仔猪外周血Et玫瑰花环形成率和T淋巴细胞转化率的影响。结果表明 :哺乳仔猪外周血Et玫瑰花环形成率、淋巴细胞转化率LTT(PHA、LPS刺激原)随日龄增长呈线性加大的趋势(P<0.05) ;断奶应激均使Et、LTT(PHA)、LTT(LPS)降低(P<0.05)。断奶越早 ,断奶后血液LTT(PHA/LPS)下降的幅度越大 ,恢复与哺乳猪相同水平的时间越长 ,其中14日龄断奶后1～3周 ,21、28日龄断奶后1周LTT(PHA)显著低于对照组(P<0.05) ;14日龄断奶后1～4周 ,21日龄断奶后1～3周 ,28日龄断奶后1～2周 ,35日龄断奶后1周LTT(LPS)显著低于对照组(P<0.05)。     

奶牛泌乳曲线数学模型拟合和早期预报

本研究根据北京地区黑白花奶牛500个完整泌乳期的产奶记录资料研究了Wood模型、改进多项式模型、回归模型的拟合以及回归模型的预报情况。拟合结果表明,利用Wood模型来估计北京地区黑白花奶牛产奶量是可行的,但在取样间隔天数较大时估计奶量与实际奶量间有较大的偏差。鉴于此,作者提出了改进多项式模型,采用了ALI的回归模型,按对Wood模型进行拟合的同样方法对这两个模型进行了拟合,拟合精确度都较Wood模型有所改进。取样间隔天数大时,改进多项式模型的拟合精确度提高的幅度较大。回归模型的预报奶量与实际奶量呈较一致的变化规律,这对早期选种具有一定的实践意义。     

线叶菊草地地下植物量及其生长率的动态分析

为探讨线叶菊＋贝加尔针茅草地地下植物量的分布，季节动态，生长率动态及其相关因素，对采“Ｈａｏ沟法”定期测定其地下植物量，结果表明，地下植物量的８１．２８％，分布在０～２０ｃｍ土层内，季节变化曲线呈“Ｕ”线，早春与晚秋时地下植物量较大，而低谷出现在７月下旬至８月上旬，地上部分在旺盛生长对地下部分贮藏的营养物质有较大的依赖性，在生长季末期，活根量的净积累效率最高，地下部分的净生产力为５９８．５６ｇ／ｍ