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文章旨在研究日粮添加发酵玉米秸秆对肉牛生长性能、养分表观消化率和经济效益的影响。试验将45头西门塔尔杂交公肉牛随机分为3组,每组3个重复,每个重复5头牛。分别向基础饲料中添加0%、15%和30%的发酵玉米秸秆作为试验日粮。试验持续70?d(预饲期10?d,正试期60?d)。试验结果表明,日粮添加30%发酵玉米秸秆显著提高了肉牛的平均日增重、平均日采食量和终末体重(P <0.05);显著降低肉牛料重比(P <0.05);日粮添加15%发酵玉米秸秆显著提高了肉牛平均日采食量(P <0.05),但对肉牛增重和料重比无显著影响(P> 0.05)。日粮中添加15%和30%发酵玉米秸秆显著提高了肉牛粗蛋白质表观消化率(P <0.05);肉牛中性洗涤纤维表观消化率随发酵玉米秸秆添加量提高而升高(P <0.05);日粮中添加30%发酵玉米秸秆显著提高了肉牛酸性洗涤纤维表观消化率(P <0.05);日粮添加发酵玉米秸秆对肉牛干物质、粗脂肪、钙和磷的表观消化率无显著影响(P> 0.05)。日粮添加30%发酵玉米秸秆小幅增加了日粮成本,肉牛的增重成本降低,毛利... 相似文献
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试验采用3×4设计来考察日粮中添加乳糖和海藻提取物(来源于海带属.主要成分为昆布多糖和岩藻依聚糖)对断奶仔猪生产性能和养分消化率的影响。乳糖添加量分别为60、150和250g/kg,海藻提取物添加量分别为0、1、2和4g/kg。试验选择24日龄、7.5±1kg断奶仔猪384头,按体重随机分为12个处理组(每个处理组8个重复)。结果表明,试验全期(0~21d).乳糖X海藻提取物互作对断奶仔猪日增重(ADG)影响显著.当低和中等乳糖添加组13粮中海藻提取物的添加量增加到2g/kg时.断奶仔猪日增重显著增加(P〈0.05)。然而.当高乳糖组日粮中海藻提取物的添加量增加到lg/kg以上水平时.断奶仔猪日增重没有进一步提高。在试验期间.乳糖×海藻提取物互作对断奶仔猪饲料转化率(FCR)影响显著(P〈0.05)。当低乳糖添加组日粮中海藻提取物的添加量增加到4g/kg时.断奶仔猪饲料转化率极显著增加(P〈0.01)。当中等乳糖添加组日粮中海藻提取物的添加量增加到2g/kg时.断奶仔猪饲料转化率显著增加。但是.在高乳糖添加组13粮中增加海藻提取物的添加量对断奶仔猪饲料转化率没有影响(P〉0.05)。在整个试验期间.随着日粮中海藻提取物添加量的增加.断奶仔猪平均日采食量(ADFI)呈线性增加(P〈0.05)。随着日粮中乳糖添加量的增加.断奶仔猪对灰分的消化率呈线性增加(P〈0.01),氮(N)和中性洗涤纤维的消化率呈二次曲线规律下降(P〈0.01)。总之,在每个不同乳糖水平日粮中添加海藻提取物水平不同对断奶仔猪的影响效果不同。在饲粮中添加高浓度乳糖(60g/kg)或海藻提取物可通过提高养分消化率来提高断奶仔猪的日增重和饲料转化效率.也可以减轻仔猪断奶后发生的一些常见问题. 相似文献
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选用3头装有永久瘤胃瘘管的云南黄牛,饲喂5种含不同加工处理(粉碎、粉碎蒸汽、干碾压、湿碾压、蒸汽压片)玉米的日粮,在精粗比为50:50的条件下,采用5×5不完全拉丁方设计,测定5种日粮中干物质,有机物质、蛋白质、淀粉、中性洗涤纤维、酸性洗涤纤维的消化率以研究不同处理对饲料消化率的影响。试验结果表明,在5组处理玉米日粮中,蒸汽压片玉米日粮组干物质(DM)、有机物质(OM)和粗蛋白(cP)全消化道消化率显著提高(P〈0.05)。全消化道淀粉消化率各处理玉米日粮组间存在差异,蒸汽压片与粉碎蒸汽玉米日粮组显著高于干碾压与湿碾压玉米日根组(P〈0.05),而与粉碎玉米日粮组间没有显著差异(P〉0.05)。中性洗涤纤维(NDF)与酸性洗涤纤维(ADF)的消化率在5组处理玉米日粮间没有显著差异(P〉0.05). 相似文献
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观察添加刺五加提取物对绵羊瘤胃发酵及养分利用的影响,以揭示其对瘤胃发酵影响的机理。选择6只健康的小尾寒羊,随机分为2组,采用交叉试验设计,分别添加0、50mg/kg刺五加水提取物。不同时间点采集试验羊的瘤胃液,测定pH值、氨态氮(NH,-N)浓度、挥发性脂肪酸(VFA)浓度;收集试验动物粪便,测定日粮中各营养物质的表观消化率。试验结果表明:刺五加的添加可以降低绵羊瘤胃NH,-N浓度,使瘤胃液pH值变化趋势减缓;明显提高日粮酸性洗涤纤维(ADF)和中性洗涤纤维(NDF)的表观消化率(P〈0.05),显著提高瘤胃液乙酸和总挥发性脂肪酸(TVFA)浓度(P〈0.05)。该试验为刺五加添加剂在反刍动物中的应用奠定基础,同时对中草药添加剂日粮在反刍动物中的使用提供借鉴。 相似文献
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选择1日龄、健康、正常的长白猪、大太猪(大白猪(6)×太湖猪(♀))和太湖猪各24头,每个品种设为一个处理.每个处理按体重一致原则设4个重复。每个重复6头猪(公母各半),采用外源指示剂法,分别测定它们在42~45日龄和72~75日龄对日粮养分(干物质、粗蛋白质、粗脂肪、中性洗涤纤维、酸性洗涤纤维、能量)的表观消化率。结果表明:在42~45日龄时.大太猪对粗蛋白质的消化率显著高于长白猪(P〈O.05):大太猪对中性洗涤纤维和酸性洗涤纤维的消化率极显著高于长白猪(P〈0.01):大太猪对粗脂肪和能量的消化率分别极显著和显著高于太湖猪(P〈0.01或P〈O.05):太湖猪对中性洗涤纤维和酸性洗涤纤维的消化率都极显著高于长白猪(P〈O.01)。在72~75日龄时.大太猪对粗蛋白质的消化率显著高于长白猪和太湖猪(P〈0.05);大太猪和太湖猪对中性洗涤纤维的消化率极显著高于长白猪(P〈0.01);3种猪对干物质、粗脂肪、酸性洗涤纤维和能量的消化率差异均不显著(P〉O.05)。所以,在本试验条件下,大太猪对粗蛋白质的消化率高于长白猪和太湖猪:大太猪和太湖猪对中性洗涤纤维的消化率高于长白猪。 相似文献
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选用36头经产奶牛,根据泌乳期、上一泌乳期305d产奶量和预产期,采用随机区组设计分为4组,研究甘油(0、100、200和300g/d)对泌乳早期奶牛血液指标和尿酮浓度的影响。结果表明:日粮添加甘油后,200g/d组和300g/d组血浆葡萄糖浓度显著高于对照组(P〈0.05),而血浆游离脂肪酸和β-羟丁酸浓度显著低于对照组(P〈0、05);200g/d组和300g/d组尿酮浓度显著低于对照组和100g/d组(P〈0.05)。根据试验结果,甘油适宜添加量为200g/d。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献