产蛋鸡合理应用植物磷的方式及其意义

在几种不同的植物磷利用方式中，以产蛋鸡最具节省磷源、降低环境污染和饲料成本，以1994年美国NRC所用非植酸磷能达到此目的，而且科学性较强，简便易行。     

不同水平植酸酶在产蛋鸡饲粮中应用效果的分析

试验采用产蛋高峰期（３０周龄）海兰褐商品蛋鸡。在饲料中用３００ＦＴＵ植酸酶替代２２克无机磷,相当于在每吨饲料中添加１５０克商品植酸酶替代１３８千克磷酸氢钙（ＤＣＰ）或１５４千克可利用磷。观察植酸酶完全替代磷酸氢钙（后对产蛋鸡生产性能和体况的影响。根据试验结果表明,可以在产蛋鸡饲料中用商品植酸酶替代目前使用的磷酸氢钙。根据我国目前的磷酸氢钙品质（含氟量）状况,在蛋鸡饲料中使用植酸酶能够减轻以至于杜绝磷酸氢钙导致的氟中毒问题。同时可以预见,使用植酸酶可以大幅度降低排泄物的含磷量,减少磷对自然环境的污染,另外在饲料成本略有下降的情况下可有效地改善蛋鸡的生产性能。     

植酸酶替代产蛋鸡饲料中磷酸氢钙的研究

本试验目的是利用植酸酶可以水解饲料中植酸的原理，探讨在国内蛋鸡的实际生产条件下，商品植酸酶替代磷酸氢钙的效果和评价实际可应用性。试验选用22─46周龄北京红鸡，在饲料中用300FTU植酸酶替代2.2克无机磷（相当于在每吨饲料中添加60克商品植酸酶替代13.8公斤磷酸氢钙─DCP，或1.54公斤可利用磷），观测植酸酶对产蛋鸡生产性能和体况的影响。结果表明：用300FTU植酸酶替代2.2克无机磷至少可以保持产蛋鸡的生产性能不变。其中：产蛋率（＋2.2％）、日耗料量（＋l.4％）、饲料报酬（一2.0％）、破蛋率（一2．0％）、死淘率（一4.l％）和胫骨总灰分含量（＋3.6％）均优于对照组，但差异不显著；而日产蛋量（＋4.1％）、体增重（十47％）、胫骨钙含量（＋4.8％）则显著优于对照组（P＜0.05）。根据试验结果，认为可以在产蛋鸡饲料中用商品植酸酶替代目前使用的磷酸氢钙。还可以认为，根据我国目前的磷酸氢钙品质（含氟量）状况，在蛋鸡饲料中使用植酸酶能够大幅度减轻以至于杜绝磷酸氢钙导致的氟中毒问题。同时能够预见，使用植酸酶可以大幅度降低排泄物的含磷量，减少磷对自然环境的污染。植酸酶在产蛋鸡饲料中具有重要的现实应用意义。     

植酸酶和纤维素酶对蛋鸡生产性能的影响及蛋鸡非植酸磷需要量研究

选用18周龄海赛克192只 ,研究了玉米—豆粕型日粮中添加植酸酶和纤维素酶对蛋鸡生产性能的影响以及蛋鸡对非植酸磷的需要量。采用2×2×2因子正交试验设计(L827) ,基础日粮为玉米—豆粕型 ,含玉米60 % ,豆粕27 % ,两个水平非植酸磷(0.38 %、0.16 %) ,两个水平植酸酶(300IU/kg,0) ,两个水平纤维素酶(0.1 % ,0)。试鸡随机分为8组 ,每组4个重复 ,每个重复6只鸡。试验饲养期共7个月。试验结果表明 ,玉米—豆粕型日粮添加0.1 %纤维素酶有降低试鸡日采食量的趋势。添加300IU/kg 植酸酶和0.1 %纤维素酶及其他各因素处理对蛋鸡全试验期平均产蛋率…     

促进植酸酶应用

为提高磷的利用率,消除植酸的抗营养作用,在过去30年植酸酶被越来越多地用于动物饲料。目前,高效的植酸酶已经面市,但植酸酶的功效仍有提升的空间。     

日粮不同总磷水平及添加植酸酶对蛋鸡生产性能的影响

以360羽72周龄伊莎父母代蛋种鸡为试验动物,随机分为五个组,研究饲喂含不同总磷水平的日粮(分别为0.35%, 0.40%, 0.45%,0.50%和0.55%五个水平)及添加植酸酶(500u/kg)对蛋鸡生产性能以及钙磷表观代谢率的影响.对试验期蛋鸡产蛋率、平均蛋重、耗料量、料蛋比、蛋壳厚度、蛋型指数和破蛋率的统计结果表明:总磷水平在0.40%左右时,蛋鸡的产蛋率最高,且差异显著(P<0.05),日粮不同总磷水平对蛋鸡其他它生产指标的影响差异不显著(P>0.05).对试鸡钙磷表观代谢率的计算表明:低磷日粮中的磷的表观代谢率较高,而钙的表观代谢率较低,高磷日粮中钙磷代谢则相反.结论:日粮总磷在加入植酸酶(500u/kg)的情况下0.40%水平即能使蛋鸡发挥比较好的生产性能,且不会出现缺乏症状.若综合产蛋率、耗料量、料蛋比三个因素,蛋鸡对总磷的需求水平为0.40%,若考虑平均蛋重、破蛋率这两个因素,则蛋鸡对总磷的需求水平为0.55%.     

日粮不同总磷水平及添加植酸酶对蛋鸡生产性能的影响

以360羽72周龄伊莎父母代蛋种鸡为试验动物,随机分为五个组,研究饲喂含不同总磷水平的日粮（分别为0.35%,0.40%,0.45%,0.50%和0.55%五个水平）及添加植酸酶（500u/kg）对蛋鸡生产性能以及钙磷表观代谢率的影响。对试验期蛋鸡产蛋率、平均蛋重、耗料量、料蛋比、蛋壳厚度、蛋型指数和破蛋率的统计结果表明：总磷水平在0.40%左右时,蛋鸡的产蛋率最高,且差异显著（P〈0.05）,日粮不同总磷水平对蛋鸡其他它生产指标的影响差异不显著（P〉0.05）。对试鸡钙磷表观代谢率的计算表明：低磷日粮中的磷的表观代谢率较高,而钙的表观代谢率较低,高磷日粮中钙磷代谢则相反。结论：日粮总磷在加入植酸酶（500u/kg）的情况下0.40%水平即能使蛋鸡发挥比较好的生产性能,且不会出现缺乏症状。若综合产蛋率、耗料量、料蛋比三个因素,蛋鸡对总磷的需求水平为0.40%,若考虑平均蛋重、破蛋率这两个因素,则蛋鸡对总磷的需求水平为0.55%。     

中型褐壳产蛋鸡饲粮非植酸磷适宜水平的研究

用20周龄的商品代北京红开产蛋鸡150只进行饲养试验和磷代谢试验，研究饲粮非植酸磷水平对20－40周龄阶段蛋鸡产蛋性能、蛋及蛋壳品质、血清生化特性和饲粮植酸磷表观消化利用率的影响，进而从多方面综合评价中型褐壳产蛋鸡的饲粮非植酸磷适宜水平，同时测定产蛋鸡对饲粮植酸磷的消化能力。试鸡按完全随机设计以体重随机分为5个处理组，分别喂以含非植酸磷0．20％、0．25％、0．30％、0．35％和0．40％及含钙量均为3．5％的玉米一豆粕型饲粮。饲粮非植酸磷水平对鸡的产蛋率、蛋重、产蛋量、采食量、饲料效率、蛋壳强度、蛋品哈氏单位、蛋形指数、血清白蛋白、球蛋白和碱性磷酸酶（AKP）活性无明显影响（P＞0．18），而对蛋壳厚（P＜0．04）、蛋壳重（P＜0．07）及植酸磷表观消化率（P＜0．05）有显著影响。蛋壳厚、蛋壳强度及蛋壳重 0．20％非植酸磷水平组最大，此时鸡对饲粮植酸磷的表观消化率高达70．5％，但随饲粮非植酸磷水平的增加，上述4项指标均恒定降低，在0．30％－0．40％非植酸磷水平，蛋壳厚（P＜0．04）和蛋壳重（P＜0．07）明显降低，在0．25％和0．40％时植酸磷表观消化率分别比0．20％水平组降低17．7T和21．4个百分点（P＜0．05）。结果表明，北京红中型褐壳产蛋鸡在20－40周龄阶段的饲粮非植酸磷水平以0．20％（实测值为0．23％）为宜；中型褐壳产蛋鸡对饲粮植酸磷有很强的消化能力。     

植酸酶替代产蛋鸡日粮中磷酸氢钙的研究

试验选用640只23周龄产蛋鸡,研究应用植酸酶减少日粮中磷酸氢钙的用量后,对产蛋鸡生产性能、骨中钙磷含量和营养物质表观消化率的影响.试验分4组,各组日粮植酸酶水平为0、300、400、550 U/kg,相应各组日粮的磷酸氢钙含量为1.6%、0.55%、0.29%、0.29%.结果表明,各组的产蛋率和料蛋比差异不显著(P＞0.05).试验各组蛋鸡的死淘率与对照组相比有不同程度下降.试验各组胫骨中钙的含量和对照组差异不显著(P＞0.05),试验1组胫骨中磷的含量显著高于其他各组(P＜0.05),灰分含量各组之间差异不显著(P＞0.05).试验各组粗蛋白和能量的表观消化率与对照组相比差异不显著(P＞0.05).     

Calcium and phosphorus levels in the diet of laying birds

Two hatches of crossbred pullet chicks were brooded and reared to 18 weeks of age on diets which conformed to the recommendations of the National Research Council (N.R.C.) of America for calcium and phosphorus. The pullets of each hatch were then divided at random into six laying groups. Three groups were fed diets containing 2.25, 3.14 and 5.0 per cent respectively of calcium without supplementary phosphorus and the other three groups were fed diets of the same graded calcium levels but with supplementary phosphorus to give a total inorganic phosphorus content of 0.45 per cent. When the rate of egg production in the groups receiving 2.25 per cent calcium exceeded 70 per cent an ad libitum supply of limestone grit was provided and the intake recorded. Over the twelve months of lay this resulted in an average total dietary intake level of nearly 2.65 per cent calcium.

Egg yield was not significantly influenced by the diets, except that the production of birds fed on the diet containing 5 per cent calcium without supplementary phosphorus was significantly depressed. Food intake was not adversely affected by the higher levels of ground limestone; in fact, there was a positive regression of food consumption on the percentage of calcium in the diet. Because of the greater food intake and the lower egg production, food consumed per dozen eggs and cost of food per dozen eggs were higher in the groups receiving 5 per cent dietary calcium without phosphorus supplementation, compared with groups which received lower dietary levels of calcium. There were, however, no significant differences between the various groups in income or in the margin of income over costs, per bird or per dozen eggs.

The data on egg grading showed that over the two experiments and at all levels of calcium there was no evidence of any influence of phosphorus on the combined percentage of large and standard eggs. The average percentage for the two diets with the 5 per cent level of calcium was significantly greater than the combined average for all the other diets.

The average percentage of cracked eggs for the groups with diets containing 5 per cent calcium was 9.4 per cent compared with an average of 11.1 per cent for all the other diets, but the difference was not significant.

The results suggest that there is no economic advantage in raising the calcium content of the basal diet used in these experiments beyond the level of 3.14 per cent and that at this level there appears to be no need with this basal diet to supplement the phosphorus content.     

低磷日粮中添加植酸酶对蛋鸡肠道形态结构的影响

试验旨在研究在低磷的玉米-豆粕型日粮中添加植酸酶对蛋鸡肠道形态结构的影响。选用18周龄体重、产蛋周龄相近的伊莎褐蛋鸡840羽,随机分成7组:正、负对照组及在负对照组基础上分别添加300、1000和10000U/kg的包衣状植酸酶、300U/kg的粉状及300U/kg的微丸状植酸酶(试验Ⅲ、Ⅳ、Ⅴ、Ⅵ和Ⅶ组)。结果表明:与负对照组相比,Ⅳ组的空肠绒毛高度得到了显著提高(P<0.05),Ⅲ、Ⅴ、Ⅵ和Ⅶ组与之相比无显著差异(P>0.05),但分别提高了16.49%、21.80%、15.73%以及17.29%;隐窝深度、绒毛高度/隐窝深度、黏膜厚度与之相比差异不显著(P>0.05)。各试验组间以及试验组与正对照组之间亦无显著差异(P>0.05)。因此,在低磷日粮中添加植酸酶对蛋鸡肠道结构具有一定的改善作用。     

The calcium and phosphorus requirements of laying hens

Two experiments were carried out with a modern hybrid laying strain to establish the calcium requirement for maximum egg production. The first experiment, with three calcium concentrations of 1.7, 2.8 and 3.9 per cent indicated that with 0.55 Per cent dietary phosphorus the requirement for calcium was between 1.7 per cent and 2.8 per cent. Dietary phosphorus supplements added to the mixed cereal diets containing 0.55 per cent phosphorus were without effect on production or the conclusions reached. In a subsequent experiment with four dietary calcium concentrations between 2.3 and 3.3 per cent there was no significant improvement in egg production above 2.6 per cent calcium.

In both experiments the lower production at the lower levels of calcium concentration was associated with reduced food intake. Measurements made in the first experiment showed an increasing shell thickness round the equator of the egg with increasing dietary calcium. In this experiment also a small practical test concerned with cracking of the egg shell in boiling water, indicated that incidence of cracks did not alter as the laying cycle progressed and that resistance to cracking was greatest at the highest dietary calcium concentration.     

蛋鸡日粮中添加大豆黄酮的研究进展

多数研究结果显示,大豆黄酮具有广泛的生物学功能。文章介绍了大豆黄酮的来源和理化特点,并就大豆黄酮对蛋鸡生产性能、鸡蛋胆固醇含量、鸡蛋抗氧化特性和激素内分泌进行了综述。     

大蒜素对蛋鸡产蛋性能的影响

选择 5 4周龄健康罗曼商品蛋鸡 4 0 0只 ,随机分成 5组 ,每组两个重复 ,每个重复 4 0只鸡 ,采用单因子完全随机设计 ,研究蛋鸡日粮中添加大蒜素对蛋鸡产蛋性能的影响。大蒜素的添加水平为 :0、2 0、4 0、80、16 0mg/kg。试验期为 38d。结果表明 ,蛋鸡日粮中添加 4 0mg/kg大蒜素 (大蒜素含量为4 0 % )可使产蛋率提高 11 15 % (P <0 0 5 ) ,料蛋比降低 5 94 % (P <0 0 1) ,日均采食量提高 7 6 4 % (P<0 0 1) ,经济效益显著     

Re-evaluation of calcium and phosphorus requirements in aged laying hens

1. A series of 5 trials was conducted with 401- to 650-d-old Lohmann, Yafa (local breed with brown eggshells) and Yarkon (local breed with white eggshells) hens fed for 56 to 84 d with diets containing 25 to 50 g/kg calcium (Ca) and 4.5 to 7.6 g/kg phosphorus (P). 2. Increasing dietary Ca from 24-25 to 36-40 g/kg improved egg production, shell weight (SW) and shell thickness (ST), and decreased mortality. 3. Increasing dietary Ca to 48 to 50 g/kg did not affect egg production but increased SW and/or ST. In one out of the 4 trials, this effect was not significant, most likely because of the high shell quality of the eggs from the Yafa hens used for this trial. 4. Dietary P content of 4.5 g/kg (1.0 g/kg added inorganic P) appears to be sufficient for maintaining egg production and shell quality in aged laying hen given 36 to 40 g/kg Ca. 5. Increasing dietary Ca above 40 g/kg may require a higher dietary P content.     

Dietary phosphorus supply, egg-shell deposition and plasma inorganic phosphorus in laying hens

1. In 2 experiments the effects of dietary phosphorus on relationships between plasma inorganic phosphorus concentration (Pi), shell and egg production and depletion states were measured in brown laying hens. 2. In a 12-week experiment dietary phosphorus concentrations from conventionally deficient (1.6 g non-phytate-phosphorus (PNP)/kg) to moderate excess (3.9 g PNP/kg) had little effect on egg and shell production, although there was evidence that plasma Pi concentration, when not influenced strongly by shell formation, reflected dietary phosphorus content. 3. Among birds at each dietary phosphorus concentration there was a negative linear relationship between shell weight of early eggs in the sequence and plasma Pi concentration. The relationship was apparently not affected by dietary phosphorus concentration. 4. Continued feeding of the deficient diet to 61 weeks of age did not have effects on body weight, egg and shell production, other than those associated with age, but plasma Pi and bone measurements indicated marginal phosphorus depletion. 5. In another experiment excessive dietary phosphorus (11.9 g PNP/kg) fed in a cross-over design caused small adverse effects on shell production, increased food intake and body weight and increased plasma Pi content, while there was no relationship between shell weight and plasma Pi concentration. 6. The results are consistent with an indirect effect of plasma phosphorus accumulation on shell formation, probably via an inhibitory effect on skeletal calcium release, in addition to any effect of excess dietary phosphorus on intestinal calcium availability. 7. Phosphorus requirement and status in the laying hen are complicated by the failure to recognise the contribution of digestible phytate-phosphorus to the available phosphorus supply.     

Effect of diet and natural variations in climates on the performance of laying hens

1. Laying hens raised in 3 natural tropical environments were fed on 2 series of diets with a view to defining the optimum combination of climate and dietary energy.

2. A combination of 3 growing climates, 3 laying climates (temperate, hot dry, hot humid), and 2 dietary energy concentrations (10.03 and 11.70 MJ ME/kg with protein concentrations proportional to energy) were tested for 46 weeks using 432 point‐of‐lay pullets.

3. Both growing and laying climates significantly affected most traits measured during the laying period. The patterns of egg production showed good persistency in all environments and differences observed reduced with age.

4. The difference between the high and low energy intake reduced at high ambient temperatures. Feeding low energy diets did not affect mean age at first egg, rate of lay or the egg output in the hot dry environment, nor egg weight in either hot dry or hot humid climates. Rather, feeding low energy diets resulted in improved body weight change in all 3 laying environments.

5. The growing climate and diet interacted significandy on body weight change, while highly significant interactions between laying climate and diet occurred on rate of lay, food and energy intake and egg weight during the laying period.     

蛋鸡磷营养状况检测的敏感性指标探讨

本试验在0.1%、0.2%、0.4%3个水平有效磷条件下，测定检测蛋鸡磷营养充足与否的常用指标，结果表明：6周内，0.1%有机磷对生产性能、胫骨总灰重、灰分含量、钙含量及血磷、血钙、血中碱性磷酸酶活性无显著影响（P＞0.05），对骨磷含量有显著（P＜0.05）降低作用。检测机体磷缺乏的常用指标中，骨磷含量最敏感。