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Feeding trials were performed with two groups of dairy cows receiving ammonized straw pellets supplemented with varying levels of concentrates as sole basal diet. The trials were carried out over periods of 546 days and 120 days. An annual milk production of 4217.9 kgs (calculated on the basis of 3.5% of milk fat) per cow was achieved in group I by feeding 3060.6 kgs of straw pellets and 2014.7 kgs of concentrates per animal. After subtracting all additives an amount of 2641.1 kgs of pure straw (= 52%) and of 2434.2 kgs of concentrated food (= 48%) remained so that the resulting amount of dry feed consumed per 100 kg of milk was 120.3 kg. A total of 6309.6 kgs of milk was produced per cow over a period of 546 days of trial. During this period the average weight gain per cow was 98.4 kgs. 1517.3 kgs of milk (calculated on the basis of 3.5% milk fat) per cow were produced in group II (56 cows) over a period of 105 days by feeding 892.5 kgs of straw pellets and 682.5 kgs of concentrate pellets. The concentrate pellets contained 50% of ammonized dried sugar beet chips but not extracted meals.  相似文献   

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本研究测定分析了秸秆制粒饲喂肉牛对其采食、反刍、养分表观消化率、瘤胃发酵和增重的影响,以丰富秸秆饲料化利用方式。试验选取30头18月龄左右、活重接近的西杂肉牛,随机分成3组(每组10头),分别饲喂粉碎玉米秸秆(对照组)、玉米秸秆颗粒饲料(试验Ⅰ组)及玉米秸秆精粗饲料颗粒(试验Ⅱ组)。结果表明,1)秸秆制粒饲喂肉牛,其采食、反刍、咀嚼时间均有所缩短,且每食团咀嚼时间显著少于对照组(P=0.004),而试验Ⅱ组采食时长显著低于对照组(P=0.032)。2)除试验Ⅰ组中性洗涤纤维的表观消化率显著低于对照组外(P<0.05),3组肉牛其他养分的表观消化率均无显著差异。3)秸秆粉碎制料后饲喂肉牛影响瘤胃发酵,与对照组比较,试验Ⅰ组瘤胃pH值及丁酸含量显著下降(P<0.05),而乙酸含量和乙酸/丙酸显著升高(P<0.05);试验Ⅱ组瘤胃液丁酸含量显著下降(P<0.05),乙酸/丙酸及NH3-N含量显著升高(P<0.05)。4)秸秆粉碎制粒饲喂肉牛能显著增加日增重和饲料转化率(P<0.05),试验Ⅰ组及试验Ⅱ组日增重较对照组分别高出0.36和0.38 kg,饲料转化率(料重比)分别提高27.86%和29.09%。  相似文献   

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When the herbicide chlormequat (chlorocholine chloride or CCC) was correctly used at 2 kg per hectare at the five-leaf stage of growth, the residues in wheat straw did not exceed 3 ppm. Such residual amounts remained unchanged after storage and pelleting. However, the feeding of contaminated straw pellets to cows did not result in contaimination of the milk detectable by a method which was capable of determining concentrations down to 0.05 ppm.  相似文献   

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选择20头18月龄、体重相近的西门塔尔杂种公牛(西门塔尔牛♂×本地黄牛♀),随机分为4组,日粮营养水平一致,试验组1、2和3日粮粗饲料分别以复合秸秆颗粒(50%玉米秸秆+50%苜蓿干草)替代20%、50%和80%的全株玉米青贮,对照组粗饲料全部为全株玉米青贮饲料;育肥120 d屠宰后取背最长肌测定肌内脂肪(IMF)和脂肪酸含量,以研究日粮结构及粗饲料组成对肉牛肌肉脂肪沉积、脂肪酸含量的影响.结果表明:1)复合秸秆颗粒替代部分全株玉米青贮饲料,能显著提高肉牛肌肉中IMF含量(P<0.05);2)添加不同比例复合秸秆颗粒后,肉牛的肌肉饱和脂肪酸(SFA)含量有下降趋势,但各组间无显著差异;硬脂酸(C18:0)和棕榈酸(C16:0)在各组肉牛中含量较高,分别为28.38%~32.18%和9.87%~11.48%;3)复合秸秆颗粒可提高肌肉不饱和脂肪酸(UFA)及单不饱和脂肪酸(MUFA)的含量及降低多不饱和脂肪酸(PUFA)、n-3 PUFAs含量,但各组间无显著差异;n-6 PUFAs相对含量为7.23%~10.17%,对照组显著高于试验组1和2(P<0.05);4)粗饲料组成影响肉牛部分功能性UFA,其中试验组1的γ-亚麻酸(C18:3n6)显著低于对照组和试验组3(P<0.05),而试验组2的花生四烯酸(C20:4n6)显著低于其他组(P<0.05).综上所述,复合秸秆颗粒替代不同比例全株玉米青贮饲料饲喂肉牛,能提高背最长肌IMF含量,不影响其脂肪酸组成和营养价值;复合秸秆颗粒可广泛应用于肉牛生产.  相似文献   

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The investigations with young female cattle (twin cattle, n = 30) the applicability of straw as sole roughage after the end of the suckling period was tested. Completely (I) and partly (II) pelleted rations of dried feed with a straw component of 65% each in the total rations were used. Feed intake, development of body weight, feed expenditure as well as indexes of rumen fermentation and of the concentration of some metabolism parameters in the blood serum were measured. In the complete test period (between 5th and 12th months of life, 243 days) there were not any significant differences between the groups in all registrations. Average daily weight gains of 570 g were achieved with an overall high dry matter (2.6 kg/100 kg live weight) and roughage (straw) intake (1.6 kg dry matter/100 kg live weight). The standard expenditure of energy and protein given for the stage of development was differentiatedly undercut. The energy expenditure being below the standard (ca. 10%), the total energy expenditure (kEFUcattle) was by 20 (II) and 25% (I) below standard expenditure. Energy expenditure aimed at weight gain reached very satisfactory values with 3.68 (I) and 3.79 kEFUcattle/kg weight gain (II). Protein expenditure fell short of the standard for the development stage by 14 (II) and 20% (I) resp. All parameters ascertained of the rumen and intermediate metabolism were in the physiologic standard range, as is characteristic of feeding regimes with a relatively high quota of roughage.  相似文献   

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Two lots of straw pellets (supplemented with 10% molasses), produced either with a 5 mm sieve in a hammer mill (lot A) or with a 12 mm sieve (lot B) from wheat straw, were tested with 4 sheep (wethers, average live weight 43 kg) and 4 bulls (average 170 kg). After carrying out a digestibility experiment, the mean retention time (mrt), the 80%-excretion of the markers and the transit time were ascertained with the help of 51Cr-EDTA and 103Ru-phenanthroline. The digestibility of carbohydrates (both crude fibre and N-free extracts) was significantly higher for the bulls than for the sheep. Mrt, transit time and 80%-marker excretion were ascertained as follows: (Table: see text) The better digestion performance of carbohydrates from pelleted wheat straw in bulls in contrast to the sheep is due to the longer retention time of the digesta in the digestive tract of bulls. In connection with the considerably higher ruminating capacity of cattle in comparison to sheep, a longer retention time of the straw particles (Welch, 1982) in the reticulo-rumen must be considered.  相似文献   

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By means of pelleting them one to four times (press G 600) and adding 20% sugar beet chips and 3% ammonia hydrogen carbonate at varying loose density (357-561 kg/m3) 4 straw pellet charges were produced. Significant differences could be ascertained for these pellets with regard to the fineness coefficient (I-IV 1.67; 1.30; 1.19; 0.83), hardness of pellets (5.4; 8.8; 9.4; 18.6 N/m2/10(5) and partly the loose volume. After testing four wethers per group, an energy concentration in the same sequence was ascertained as follows: 409, 388, 377 and 382 EFUcattle/kg dry matter. Apart from a higher crude fibre digestibility of groups I and II compared to III there were no significant differences in the digestibility. The measuring of feed passage time with the help of Cr2O3 did not result in directed differences. On an average of all groups, 80% of the Cr2O3 excretion was achieved after 70.5 +/- 0.7 h. The mean retention time of Cr2O3 in the digestive tract in all four groups was in average 53.3 +/- 1.2 hours. The different fineness degrees and values of the hardness of straw pellets remained without significant effects on the feed value of the straw pellets in the experiments with sheep.  相似文献   

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In investigations with 30 young cows (twin cattle) the applicability of straw materials as sole roughage was tested during the first half of their second year of life (183 feeding days). In the course of the experiment sole feed pellets (I) and partly pelleted rations of dried feed (straw pellets plus loose wheat and loose wheat straw resp.; II) were used. Approximately 72% of the dry matter intake was provided from straw materials in both groups and on an average of the test period. Weight gain and feed expenditure were ascertained and at the end of the test period also the parameters of rumen fermentation and of the concentration of some metabolism parameters in the blood serum. With feed supply being restrictive (2.2 kg dry matter/100 kg live weight), a high dry matter intake from straw (1.6 kg/100 kg live weight or 4.8 kg/animal and day resp.) and average weight gains of between 574 (I) and 582 g (II) were achieved. The standard expenditure of energy (kEFUcattle) and protein stated in the GDR feed evaluation system for this period of development was undercut by 27 (II) and 29 (I)% and 12 (II) and 18 (I)% resp. On average the expenditure of kEFUcattle/kg weight gain was 4.75 (I) and 4.98 (II) and that of digestible crude protein/kg weight gain 679 (I) and 733 g (II). Compared to standard values the expenditure of energy and feed expenditure from concentrates was 80%. Rumen fermentation conditions corresponded to those of a high cellulolytic activity (C2: C3 ratio of greater than 4: 1). The only significant differences between the groups at the time of sampling were to be observed in the total concentration of volatile fatty acids and in the pH-value in the rumen. The absolute (1/animal) and relative (1/kg dry matter intake) volume of rumen fluid varied between 65 and 70 and between 10.5 and 12.5 1. The ascertained concentration of selected metabolism parameters were within the physiologic standard range.  相似文献   

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Frozen boar spermatozoa: methods of thawing pellets.   总被引:2,自引:0,他引:2  
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A feedlot growth-performance trial and a metabolism trial were conducted to evaluate the comparative feeding value of tapioca pellets (TP). In the growth-performance trial treatments consisted of a steam-flaked corn (SFC)-based finishing diet in which a blend of 86% TP and 14% peanut meal replaced SFC at the rate of 0, 15, or 30% of diet DM. Daily weight gain (P less than .10) and DM intake (P less than .01) were greatest when 15% of the diet DM consisted of TP. Feed/gain increased linearly (P less than .01) with TP substitution into the diet. Treatment effects on carcass merit were small (P greater than .10), except that marbling score was greater with 15% TP than with either 0 or 30% TP. In the metabolism trial involving four Holstein steers, treatments consisted of an 88% concentrate diet containing 67% of either SFC or TP. Ruminal and total tract digestibility of starch was similar (P greater than .10) for SFC and TP, averaging 91 and 99%, respectively. Postruminal (P less than .05) and total tract (P less than .01) digestibility of N was lower for the TP than for the SFC diet. Total tract digestibility of N in TP was 3%. Little, if any, ADF in TP was fermented in the rumen. Total tract digestibility of ADF in TP was 16%. Total tract digestibility of DM (P less than .01) and OM (P less than .05) decreased 7 and 5%, respectively, with TP substitution for SFC. Virtually all the difference in OM digestibility could be attributed to differences in ADF excretion. The DE value of the diet decreased 11.5% (P less than .01) with the substitution of TP for SFC. It was concluded that TP can replace up to 30% of the DM in growing-finishing diets without adversely affecting ADG or DM intake of feedlot cattle. Tapioca pellets have approximately 86% the NE value of SFC.  相似文献   

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纤维素酶在0、10、20、30、40U/g的添加量下,体外酶解苜蓿草粉6、12、18、24、36h,研究酶解率的变化。结果表明,苜蓿草粉的酶解率随纤维素酶添加量的增加以及酶解时间的延长而提高。最佳的酶解时间是24h,理想的酶浓度是30U/g,此时的酶解率为17.05%。  相似文献   

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缓控释微丸的研究进展   总被引:1,自引:0,他引:1  
通过查阅国内外有关文献,对近年来缓控释微丸的辅料、制备方法、包衣技术及释药机理等的研究概况作一综述,并对其在兽药领域的发展前景进行了展望。  相似文献   

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