随着我们对猪能量代谢的理解加深，我们可以将这些知识运用到实际中来改善猪场的饲料效率。下面这些想法就是来源于本章所作的各种讨论：
1.管理好猪和栏舍减少维持能量需要
维持能量是以体重为变量的函数，但同时还受猪的活动频率、保护猪免受外部因素（疾病、应激等）免疫系统和其它系统的功能维持、体温调节的影响。
2、提高日粮总能中可消化能量的比例
即使在玉米、豆粕等高度可消化日粮中，约有15%的总能以粪便的形式浪费。生产者可通过降低日粮颗粒大小、制粒、添加外源酶等方法来提高日粮的消化率控制这一比例。
随着玉米价格的上升，颗粒大小的目标值有所下降；十年前使用的玉米颗粒大小为750微米，目前部分生产者设定其目标大小为300-350微米。Goodband等（2002）报道在1200-400微米范围内每下降100微米可将育肥猪的饲料效率提高4个点。Patience等
（2011）报道将颗粒大小的标准偏差由2.33微米下降至1.88微米，可将能量消化率由81%提高至85%。
3、检测农场日粮的实际能量含量
任何日粮中可消化或可代谢的能量的数值均存在相当大的变异，因为原料不同、不同年龄阶段猪的消化能力不同、颗粒大小不同、加工方法不同（制粒或粉剂）等。这使得营养学家很难去有效管理日粮实际能量水平。一种相对容易且不那么昂贵的解决方法是，
在日粮中添加0.4%的二氧化钛作为消化标志物，且连续添加5天。5天以后，收集栏舍内的粪便样品（约占总粪便的10%）。分析样品中标志物和能量，检测日粮中真实消化能水平。可利用所得的消化能估算代谢能数值。这种方法的一个难题是猪的食粪癖，这会对计算造成错误。实际中可通过调控试验栏地板的漏缝大小来减小这方面的影响。
4、高温季节饲喂低热增耗的日粮来减少热应激
正常条件下食物在消化和代谢过程中产生的热量，才帮助动物暖和。但在高温季节，热量却是猪生长的负面影响因素。另外，高温时猪通过自身生理调控降低采食量，这可能对健康和生理功能有益，但同时也降低了生长速率和提高了饲料效率。因此，高浊季节选择产热量最小的日粮配方是很重要的，这种日粮蛋白质、纤维水平较低，和或者高脂肪含量。
5、减小猪维持健康的能量需求
我们都知道免疫系统激活将增加维持的能量增加量。Williams等（1997）报道此可增加13%。既然健康问题降低了采食量、降低了能量摄入量，同样还降低了能量的消化率。
维持能量需要增加是能量效率降低的另一因素。疾病可给猪的能量代谢造成许多问题，所有的均可导致效率降低。因此，对于所有的猪肉生产者将疾病赶出栏舍是一项十分重要的事情，因为疾病的存在是非常昂贵的。
6、选择利用日粮能量用于维持需要效率更高的猪
对改善饲料效率的选育目前已经进展到选育降低维持能量需要量方面，这种趋势不但会持续，还会更加复杂。其将会作为选育、我们理解能量代谢的工具，且相互推进。既然维持能量需要约占每天总摄入能量的1/3，那这就为未来基因选育提供了一个合理的目标。我们还知道基因型间存在变异，那允许这种选育存在是有意义的。
7、优先考虑采食量
正如美国的养猪行业，及世界上其它国家，均面临着接受低能量日粮来降低饲料成本，提高猪的采食量带来的好处大大超过人们的想象。结果见下表10。本研究中设计了3个模型，利用Cargill的猪肉最大生长模型，反应猪在不同情况下对降低日粮能量的反应：
（1）猪可通过增加采食量来应对日粮能量水平的下降；
（2）猪不能增加自身的采食量，因此猪每天能量摄入量下降，但同样饲喂至相同的出栏体重，只是出栏天数延迟；
（3）
猪不能增加自身的采食量，因此猪每天能量摄入量下降，但猪出栏天数与模型1中一样，只是出栏体重降低。三种模型的结果差异惊人。如果与模型1保持相同的出栏天数，出栏重将从模型1中的132kg下降至模型3中的123kg。如果与模型1保持相同的出栏重，出栏天数将从模型1的125天增加至模型2中的139天。毫无疑问，未来采食量会更加重要，即使其在过去已经很重要了。以最大化采食量
为目的管理栏舍可帮助猪对低能量日粮的调整，保证每天能量摄入量正常。这样还降低了无害化饲养的成本。
8、制定单个栏舍或生产系统的采食量曲线
了解栏舍或系统内采食量的重要性不可忽视。知道饲料消耗数据并不足够，即使数据是正确的，但这仅代表了整个生长阶段的平均水平，离制定最优化饲喂方案还相差甚远。
上面第7点的生长模型很好地反应了掌握猪的采食量曲线的好处。如果采食量曲线已知，那么只需要知道何时、如何猪对低能量日粮作出反应。
原文出处：Feed efficiency in swine
The English version
With the deepened our understanding of pigs, energy metabolism, can we apply this knowledge to practice, to improve the pig feed efficiency. The following idea is derived from this chapter made a variety of discussion:
1. Manage pigs and bar reduce maintain energy needs
Maintain energy is variable weight function, but also protected by the frequency of pig, the pig from external factors (disease, stress, etc.) the function of the immune system and other systems maintenance, the influence of the temperature regulating.
2, improve diet can always in the proportion of digestible energy
Even in corn, soybean meal and other highly digestible diet, about 15% of the total waste in the form of waste. Producers may be reduced through diet, particle size and granulating, adding exogenous enzymes and other methods to improve the digestibility of the diet control the proportion.
With the rise in the price of corn, grain size of the target fell; Ten years ago using corn grain size of 750 microns, now part of the producer to set the target size of 300-300 microns. Goodband etc. (2002) reported in 1200-400 microns each fall within the scope of 100 microns of pig feed efficiency can be four points. Patience etc.
(2011) reported that the standard deviation of the particle size from 2.33 microns dropped to 1.88 microns, the energy digestibility is from 81% to 85%.
3, test farm the actual energy content of the diet
Any diet can digestion or can be, the value of energy metabolism have considerable variation, because different material, different age stages the digestive ability of pig, particle size is different, different processing methods (granules or powder), etc. This makes the nutritionists is hard to manage diet actually energy level. An easier and less costly solution is,
0.4% of titanium dioxide is added in the diet as a digestive markers, and add 5 consecutive days. Five days later, collect bar inner feces samples (accounts for about 10% of the total waste). Markers and energy analysis of samples, testing real can digest level in the diet. Can use the digestion can estimate metabolism can value. A problem of the method is that the pig coprophagia, it will cause error to calculate. Practice could be regulated and controlled by leak test bar floor size to reduce the influence of this aspect.
4, high temperature season low thermal increase consumption of diet to reduce heat stress
Under normal conditions of food produced in the process of digestion and metabolism of heat, to help animals warm. Heat in high temperature season, however, is the negative impact of pig growth factors. In addition, through its physiological regulation to reduce high temperature when pigs feed intake, which may be beneficial to health and physiological function, but also reduces the growth rate and improve the feed efficiency. High temperature season, therefore, choose the minimum heat yield formula diet is very important, this kind of diet to the low level of protein, fiber, or high fat content.
5 maintain a healthy energy demand, reducing pig
We all know that immune system activation will maintain energy addition. Williams (1997) reports that can be increased by 13%. Since health problems to reduce the feed intake, reduces the energy consumption, also reduced the digestibility of energy.
Maintain energy is need to increase the energy efficiency of another factor. Disease poses many problems for the energy metabolism of pigs, all can lead to low efficiency. Therefore, for all the pork producers will catch such disease is a very important thing, because of the existence of the disease is very expensive.
6, choose to use energy from the diet to maintain need efficient pigs
To improve the efficiency of the feed selection is now progress to reducing the breeding to maintain energy requirement, this trend will continue, not only will be more complex. It will be used as a tool of breeding, our understanding of energy metabolism, and promote each other. Since the need to maintain energy accounted for about a third of their total daily energy intake, then the gene for the future breeding provides a reasonable goal. We also know variation between genotype, exist that allow this selection is meaningful.
7, give priority to the feed intake
As America's pig industry, and other countries in the world, are faced with accept low energy diet to reduce feed costs, increase the benefits of pig feed intake more than people imagine. The results are shown in the table below 10. The three model is designed in this study, the use of Cargill pork biggest growth model, reaction pigs under different circumstances on the reduction of diet energy response:
(1) the pig can increase feed intake in response to a decrease in the level of diet energy;
(2) the pig can't increase their intake, so the pig daily energy intake decreased, but also fed to the same market weight, only such days delay;
(3)
 
Pigs can't increase their intake, so the pig daily energy intake down, but the pig market days as model 1, only such weight loss. The results of the three kinds of model difference is amazing. If the same as the model 1 to keep such days, such heavy will be decreased from 132 kg of model 1 to 3 123 kg in the model. If keep the same with model 1 are heavier, such days will be increased from 125 days of model 1 and model 2 in 139 days. There is no doubt that feed intake in the future will be more important, even if it has been important in the past. To maximize the feed intake
For objective management bar can help the pig to low energy diet adjustment, ensure the normal order of the daily energy intake. It also cut the cost of breeding innocuity.
8, formulate a single column or production system of feed intake curve
Understand the importance of column shear or in feed intake system can not be ignored. Know it's not enough to feed consumption data, even if the data is correct, but it only represent the average level of the whole growth stage, is still far from making optimal feeding scheme.
The above 7 points of growth model reflects well grasp the benefits of pig feed intake of the curve. If feed intake curve is known, then only need to know when and how the pig respond to low energy diet.
The original reference: Feed efficiency in masty swyn
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