隨著我們對(duì)豬能量代謝的理解加深，我們可以將這些知識(shí)運(yùn)用到實(shí)際中來(lái)改善豬場(chǎng)的飼料效率。下面這些想法就是來(lái)源于本章所作的各種討論：
1.管理好豬和欄舍減少維持能量需要
維持能量是以體重為變量的函數(shù)，但同時(shí)還受豬的活動(dòng)頻率、保護(hù)豬免受外部因素（疾病、應(yīng)激等）免疫系統(tǒng)和其它系統(tǒng)的功能維持、體溫調(diào)節(jié)的影響。
2、提高日糧總能中可消化能量的比例
即使在玉米、豆粕等高度可消化日糧中，約有15%的總能以糞便的形式浪費(fèi)。生產(chǎn)者可通過(guò)降低日糧顆粒大小、制粒、添加外源酶等方法來(lái)提高日糧的消化率控制這一比例。
隨著玉米價(jià)格的上升，顆粒大小的目標(biāo)值有所下降；十年前使用的玉米顆粒大小為750微米，目前部分生產(chǎn)者設(shè)定其目標(biāo)大小為300-350微米。Goodband等（2002）報(bào)道在1200-400微米范圍內(nèi)每下降100微米可將育肥豬的飼料效率提高4個(gè)點(diǎn)。Patience等
（2011）報(bào)道將顆粒大小的標(biāo)準(zhǔn)偏差由2.33微米下降至1.88微米，可將能量消化率由81%提高至85%。
3、檢測(cè)農(nóng)場(chǎng)日糧的實(shí)際能量含量
任何日糧中可消化或可代謝的能量的數(shù)值均存在相當(dāng)大的變異，因?yàn)樵喜煌⒉煌?span style="line-height:1.6;">齡階段豬的消化能力不同、顆粒大小不同、加工方法不同（制粒或粉劑）等。這使得營(yíng)養(yǎng)學(xué)家很難去有效管理日糧實(shí)際能量水平。一種相對(duì)容易且不那么昂貴的解決方法是，
在日糧中添加0.4%的二氧化鈦?zhàn)鳛橄瘶?biāo)志物，且連續(xù)添加5天。5天以后，收集欄舍內(nèi)的糞便樣品（約占總糞便的10%）。分析樣品中標(biāo)志物和能量，檢測(cè)日糧中真實(shí)消化能水平�？衫盟玫南芄浪愦x能數(shù)值。這種方法的一個(gè)難題是豬的食糞癖，這會(huì)對(duì)計(jì)算造成錯(cuò)誤。實(shí)際中可通過(guò)調(diào)控試驗(yàn)欄地板的漏縫大小來(lái)減小這方面的影響。
4、高溫季節(jié)飼喂低熱增耗的日糧來(lái)減少熱應(yīng)激
正常條件下食物在消化和代謝過(guò)程中產(chǎn)生的熱量，才幫助動(dòng)物暖和。但在高溫季節(jié)，熱量卻是豬生長(zhǎng)的負(fù)面影響因素。另外，高溫時(shí)豬通過(guò)自身生理調(diào)控降低采食量，這可能對(duì)健康和生理功能有益，但同時(shí)也降低了生長(zhǎng)速率和提高了飼料效率。因此，高濁季節(jié)選擇產(chǎn)熱量最小的日糧配方是很重要的，這種日糧蛋白質(zhì)、纖維水平較低，和或者高脂肪含量。
5、減小豬維持健康的能量需求
我們都知道免疫系統(tǒng)激活將增加維持的能量增加量。Williams等（1997）報(bào)道此可增加13%。既然健康問(wèn)題降低了采食量、降低了能量攝入量，同樣還降低了能量的消化率。
維持能量需要增加是能量效率降低的另一因素。疾病可給豬的能量代謝造成許多問(wèn)題，所有的均可導(dǎo)致效率降低。因此，對(duì)于所有的豬肉生產(chǎn)者將疾病趕出欄舍是一項(xiàng)十分重要的事情，因?yàn)榧膊〉拇嬖谑欠浅０嘿F的。
6、選擇利用日糧能量用于維持需要效率更高的豬
對(duì)改善飼料效率的選育目前已經(jīng)進(jìn)展到選育降低維持能量需要量方面，這種趨勢(shì)不但會(huì)持續(xù)，還會(huì)更加復(fù)雜。其將會(huì)作為選育、我們理解能量代謝的工具，且相互推進(jìn)。既然維持能量需要約占每天總攝入能量的1/3，那這就為未來(lái)基因選育提供了一個(gè)合理的目標(biāo)。我們還知道基因型間存在變異，那允許這種選育存在是有意義的。
7、優(yōu)先考慮采食量
正如美國(guó)的養(yǎng)豬行業(yè)，及世界上其它國(guó)家，均面臨著接受低能量日糧來(lái)降低飼料成本，提高豬的采食量帶來(lái)的好處大大超過(guò)人們的想象。結(jié)果見(jiàn)下表10。本研究中設(shè)計(jì)了3個(gè)模型，利用Cargill的豬肉最大生長(zhǎng)模型，反應(yīng)豬在不同情況下對(duì)降低日糧能量的反應(yīng)：
（1）豬可通過(guò)增加采食量來(lái)應(yīng)對(duì)日糧能量水平的下降；
（2）豬不能增加自身的采食量，因此豬每天能量攝入量下降，但同樣飼喂至相同的出欄體重，只是出欄天數(shù)延遲；
（3）
豬不能增加自身的采食量，因此豬每天能量攝入量下降，但豬出欄天數(shù)與模型1中一樣，只是出欄體重降低。三種模型的結(jié)果差異驚人。如果與模型1保持相同的出欄天數(shù)，出欄重將從模型1中的132kg下降至模型3中的123kg。如果與模型1保持相同的出欄重，出欄天數(shù)將從模型1的125天增加至模型2中的139天。毫無(wú)疑問(wèn)，未來(lái)采食量會(huì)更加重要，即使其在過(guò)去已經(jīng)很重要了。以最大化采食量
為目的管理欄舍可幫助豬對(duì)低能量日糧的調(diào)整，保證每天能量攝入量正常。這樣還降低了無(wú)害化飼養(yǎng)的成本。
8、制定單個(gè)欄舍或生產(chǎn)系統(tǒng)的采食量曲線(xiàn)
了解欄舍或系統(tǒng)內(nèi)采食量的重要性不可忽視。知道飼料消耗數(shù)據(jù)并不足夠，即使數(shù)據(jù)是正確的，但這僅代表了整個(gè)生長(zhǎng)階段的平均水平，離制定最優(yōu)化飼喂方案還相差甚遠(yuǎn)。
上面第7點(diǎn)的生長(zhǎng)模型很好地反應(yīng)了掌握豬的采食量曲線(xiàn)的好處。如果采食量曲線(xiàn)已知，那么只需要知道何時(shí)、如何豬對(duì)低能量日糧作出反應(yīng)。
原文出處：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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