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81.
OBJECTIVE: To determine the changes in Ca, P, Mg, Na, K, S, Cu, Fe and Zn concentrations of milk during the lactation in pasture-fed Thoroughbred mares and then calculate the dietary mineral requirements of the sucking foal and the lactating mare. PROCEDURE: Milk was sampled on days 1, 3, 7, 14, 21, 28 and at various times between 55 to 65, 85 to 95 and 135 to 150 days after parturition from 21 pasture-fed mares. The concentrations of macro- and micro-elements in the milk were determined by inductively coupled plasma emission spectrometry. RESULTS: Concentrations (mg/L) of these elements were highest in colostrum (Mg 302, Na 561, K 955, S 1035, Cu 0.76, Fe 0.79 and Zn 5.5) except for Ca (1245) and P (895), which where highest on day 7. The mean milk mineral element concentrations (mg/L) over days 55 to 150 were Ca 843, P 543, Mg 47, Na 120, K 590, S 219, Cu 0.19, Fe 0.34 and Zn 2.1. The mean plasma element concentrations (mg/L) over the same period were Ca 120, P 77.1, Mg 17.0, Na 3110, K 168, S 983, Cu 1.1, Fe 1.5 and Zn 0.49. Concentration gradients between plasma and milk were observed and, in the case of Ca, P, Mg, K and Zn, their concentrations in milk were greater than those in plasma, while a reverse situation was observed for Na, S, Cu and Fe. CONCLUSION: With the exception of Ca and P, the highest concentrations of mineral elements were observed in the colostrum. The nursing foal should have access to good pasture or creep feed, because the intakes of Ca, P and Cu from milk may be less than optimum to meet the daily mineral element requirements.  相似文献   
82.
稚蚕人工饲料中桑绿枝粉的添加效果及加工特点   总被引:16,自引:0,他引:16  
在家蚕稚蚕人工饲料中分别添加 15 %的桑绿枝粉、冬桑条粉、桑皮粉等 ,并与豆腐渣、市售纤维素粉末等进行了对照试验 ,结果以添加桑绿枝粉的稚蚕人工饲料各项成绩最为理想 ,稚蚕对其有良好的摄食性 ,从而为研制稚蚕低成本人工饲料开辟了新的原料来源  相似文献   
83.
The influence of three diets, comprising dam's milk (DM) from the same farm, commercial milk replacer with (CMRL) or without 3.2% lactose (CMR), on the duration and intensity of Candida glabrata shedding in the faeces of preweaned calves following experimental oral infection was examined. Shedding of other potential enteric pathogens was also monitored. The duration and intensity of C. glabrata shedding in DM-fed calves were reduced significantly compared with the calves fed the two diets based on milk replacers. Consequently, feeding calves with DM might disrupt the infective cycle, resulting in the yeast's elimination from a farm. In the CMR and CMRL groups, the periods of intensive shedding of C. glabrata and rotavirus overlapped but no diarrhoea was associated with the shedding of either microorganism. There was no evidence that lactose diminished colonization in vivo.  相似文献   
84.
将48头杜×长×大三元杂交生长猪随机分为两组,分别饲喂正常磷水平日粮和无磷酸氢钙日粮,结果表明:与正常磷水平日粮相比,无磷酸氢钙日粮可显著提高磷的表观消化率(P<0.05),增加猪场的纯收入,减少粪中磷的排放以保护猪场周边的生态环境。  相似文献   
85.
利用人工瘤胃体外产气法研究不同精粗比(0:1和1:1)日粮类型时中链脂肪酸对甲烷产量的影响。结果显示,体外培养24h,添加脂肪酸对甲烷产量的抑制作用不受日粮类型的影响(P>0.05);与不添加酸的对照相比,添加50mg未酯化月桂酸(C12:0)及月桂酸和肉豆蔻酸(C14:0)以3:2的比例组成的混合物(50mg)可分别抑制甲烷产量的22.2%(P<0.01)和11.8%(P<0.05);添加50 mg未酯化C14:0使甲烷产量降低3.4%(P>0.05);不同日粮类型上饲料产气量、瘤胃液pH值和氨氮浓度差异显著(P<0.01)。  相似文献   
86.
本文主要从多不饱和脂肪酸(PUFA)的来源、合成途径、作用机理及使用效果等方面阐述了多不饱和脂肪酸影响猪繁殖性能的研究进展。  相似文献   
87.
The purpose of the experiment was to study the effect of Momordica grosvenori saponins on improving the effect of high-sucrose/high-fat diet combined with streptozotocin induced type 2 diabetes in rats.The type 2 diabetes rat model was established with a high-sucrose and high-fat diet combined with streptozotocin.Successfully modeled rats were given the total saponins of Momordica grosvenori (100,200,400 mg/kg) or metformin (268 mg/kg) by gavage,once a day for 4 weeks.Recording the "three more and one less"index (24 h internal urine output,water intake and feed intake,body weight);Detecting of biochemical indicators,analysis of fasting blood glucose (FBG),serum total cholesterol (TC),triglycerides (TG),low-density lipoprotein cholesterol (LDL-C),high-density lipoprotein cholesterol (HDL-C),insulin (INS),catalase (CAT),superoxide dismutase (SOD),malondialdehyde (MDA),alanine aminotransferase (AST),aspartate aminotransferase (ALT),blood urea nitrogen (BUN) and creatinine (Cr) levels.Hematoxylin-eosin staining (HE) was used to observe the pathological changes of the pancreas.Compared with the model group,the feed intake,water intake,urine output,blood indicators FBG,INS,MDA,TC,TG,BUN and Cr levels,AST and ALT activities were significantly or extremely significantly decreased in the total saponins of Momordica grosvenori each dose group and metformin group (P<0.05;P<0.01),while CAT,SOD activities and HDL-C level were significantly or extremely significantly increased (P<0.05;P<0.01).In pancreatic tissue,the number of pancreatic cells was increased significantly,and the pathological damage of the pancreas was significantly reduced. Momordica grosvenori saponins and metformin had obvious effects on improving glucose metabolism disorders,and at the same time could significantly reduce insulin resistance,enhance the body’s ability to resist oxidative stress and improve liver and kidney functions.  相似文献   
88.
本试验选取18只体重约42 kg的空怀小尾寒羊母羊,按体重分为3组(n=6),分别喂给以玉米秸秆为粗饲料的精粗比为20∶80(日粮1)、30∶70(日粮2)和40∶60(日粮3)的日粮,以研究不同精粗比日粮对空怀小尾寒羊母羊消化代谢的影响。结果表明,3组羊只的有机物采食量分别为970.1±95.1、1137.3±144.8和1279.2±138.7 g/d.只;玉米秸秆的采食量分别为834.3±75.6、856.1±110.2和822.0±121.7 g/d.只;有机物表观消化率分别为52.53%±5.16%、55.73%±2.64%和59.68%±1.95%;粗蛋白质表观消化率分别为58.73%±7.60%、61.05%±2.61%和62.84%±2.33%;纤维素表观消化率分别为57.42%±6.04%、56.12%±1.06%和53.42%±3.83%;氮保留量分别为0.62±1.17、3.15±2.22和5.87±1.56 g/d.只;钙保留量分别为0.39±0.05、0.59±0.10和0.79±0.06 g/d.只;磷保留量分别为0.40±0.04、0.59±0.06和0.82±0.05 g/d.只;所获得的可消化能分别为9.40±1.37、12.31±2.05和15.09±1.83 M J/d.只;试验期体增重分别为-12.4±46.1、101.2±60.0和157.1±96.5 g/d.只。由此得出结论,在以玉米秸秆为粗饲料的条件下,当空怀小尾寒羊母羊日粮中的精料量为20%时,体重难以维持,并且氮保留率也低(3.29%);增加日粮中的精料量到30%或40%时,可提高日增重,并且使氮保留率达到13.82%或22.09%。增加日粮的精料比例可不同程度地提高有机物、能量、粗蛋白质和钙磷的表观消化率,但对纤维素类物质的消化有一定影响。增加动物的可消化能量供应可大幅度改善氮的利用率,也增加钙磷的保留量。提高日粮的精粗料比例,并不影响小尾寒羊对玉米秸秆的采食量。  相似文献   
89.
从猪胴体脂肪酸组成特点及其改变的可能性入手 ,系统综述了饲粮中添加不同种类与水平的油脂、全脂油籽与饼粕对猪胴体脂肪酸组成的改善 ,以及维生素E、硒、维生素C、类胡萝卜素与肌肽对不饱和脂肪酸含量较高的胴体脂肪氧化稳定性的增强效应 ,并指出了今后的研究和发展方向。  相似文献   
90.
A stochastic-linear program Excel workbook was developed that consisted of 2 worksheets illustrating linear and stochastic program approaches. Both approaches used the Excel Solver add-in. A published linear program problem served as an example for the ingredients, nutrients, and costs and as a benchmark in the development of the linear and stochastic programs. Standard deviations for ME and nutrients were taken or calculated from CV, and from a commercial publication of sources for amino acids. The Excel spreadsheet was set up so that the calculated margin of safety (MOS) value, according to the requested probability, was the same for both the linear and stochastic programs. As an example, the probability for meeting the nutrient value for protein was compared at 50% (MOS = 0) and 69% (MOS = 0.5) by using both linear and stochastic programming. Spreadsheet results illustrated the flexibility, accuracy, and precision of the stochastic program over the linear program in meeting the requested nutrient probability.  相似文献   
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