Liquid methionine added to diets for lactating sows leads to both more fat and lactose concentration in the milk as well as a better gut absorption of nutrients in the suckling piglets’ guts. Jointly, these factors explain a higher piglet body weight before and after weaning.

在哺乳母豬日糧中添加液態(tài)蛋氨酸有助于提高乳汁中的脂肪及乳糖含量，同時(shí)可以提高哺乳仔豬腸道對(duì)營(yíng)養(yǎng)物質(zhì)的吸收率?？傮w而言，這都可以提高仔豬斷奶前后的體重。

Nutritionists must find solutions to feed the modern and hyper-prolific sows and develop new strategies to meet increasing nutrient requirements. Lactation is an essential phase, as sow milk quantity and quality play a central role in the growth of suckling piglets.

營(yíng)養(yǎng)學(xué)家需要找到新辦法飼喂現(xiàn)代化的高產(chǎn)母豬，滿足其不斷增長(zhǎng)的營(yíng)養(yǎng)需求。母乳量及質(zhì)量在哺乳仔豬生長(zhǎng)中發(fā)揮著重要作用，因此，保證哺乳期營(yíng)養(yǎng)十分重要。

Comparing methionine

Recently, a trial was carried out in China on cross-bred primiparous sows in order to compare lactating sow diets with an extra supply of methionine with a control diet containing 0.25% of total methionine, at a level in agreement with the recommendations of the United States National Research Council (NRC). Three methionine sources are available for the feed industry. In this trial, 2 forms of methionine were compared: a powder form, DL-methionine (1.34 kg/tonne) and a liquid form: DL-hydroxy methionine, DL-HMTBA (1.51 kg/tonne).

對(duì)比試驗(yàn)

近期，中國(guó)進(jìn)行了一項(xiàng)實(shí)驗(yàn)，實(shí)驗(yàn)對(duì)象為雜交的初產(chǎn)母豬，目的是對(duì)比日糧中不同蛋氨酸含量對(duì)母豬的影響，其中一組添加了額外的蛋氨酸，對(duì)照組的蛋氨酸添加量則為NRC(美國(guó)國(guó)家研究理事會(huì))推薦量0.25%。飼料行業(yè)中有3種蛋氨酸來源。該試驗(yàn)對(duì)其中2種進(jìn)行了對(duì)比：粉末狀DL-蛋氨酸(1.34kg/t)、液態(tài)DL-羥基氨基酸即DL-HMTBA(1.51kg/t)。

Compared to the control diet and the DL-methionine diet, the diet containing DL-HMTBA leads to a significant improvement of fat and lactose content of the milk of the sows (Figure 1), the 2 sources of energy supply for suckling piglets. The authors also demonstrated that a better milk composition stimulates intestinal gene expression and increases absorption capacity of the suckling piglets gut.

與對(duì)照組及添加DL-氨基酸的日糧相比，添加了DL-HMTBA的日糧使母豬乳汁中的脂肪及乳糖含量顯著提高(見圖1)。同時(shí)，研究員也表示，更優(yōu)質(zhì)的乳汁成分可以刺激腸道基因表達(dá)，并提高哺乳仔豬腸道的吸收率。

As a consequence of the higher nutritional milk content regarding macronutrients and amino acids, the body weight of suckling piglets at day 14 post-farrowing in the DL-HMTBA group was significantly higher (+510 g) than in the control group and tended to be higher (+310 g) than in the DL-methionine group.

由于乳汁中含有更多多量元素及氨基酸，DL-HMTBA組的哺乳仔豬在分娩后第14天，體重顯著高于對(duì)照組仔豬(+510g)，并且高于DL-蛋氨酸組的仔豬(+310g)。

圖1 飼喂不同來源蛋氨酸的母乳中脂肪和乳糖的含量

Figure 1 - Content of fat and lactose in milk of sows fed with different sources of methionine

Body weights increase

These new data confirm the better efficacy of the liquid form of methionine which were observed earlier by researcher Hao Li and his team, affiliated to Sichuan Agricultural University, China. In that trial, where both sows and piglets received a diet with increased levels of sulphur amino acids through DL-HMTBA or DL-methionine, the scientists demonstrated that the body weight of 35 day old piglets was significantly higher when sows and piglets received methionine as DL-HMTBA compared with DL-methionine, also seeFigure 2.

體重增長(zhǎng)

這些新數(shù)據(jù)證實(shí)了四川農(nóng)業(yè)大學(xué)研究員Hao Li團(tuán)隊(duì)的觀點(diǎn)——液體形式的蛋氨酸功效更佳。在該試驗(yàn)中，母豬和仔豬飼料中通過添加DL-HMTBA或DL-蛋氨酸補(bǔ)充更高水平的含硫氨酸。研究人員發(fā)現(xiàn)DL-HMTBA組的35日齡仔豬的體重要明顯高于DL-蛋氨酸組，見圖2。

注：TSAA/Lys=含硫氨基酸/賴氨酸

圖2 35日齡仔豬體重(kg)

Figure 2 Piglet weight at 35 days (kg).

Furthermore, those piglets had a better gut morphology, with higher villus heights and villus height/crypt depth ratio leading to a better absorption capacity. Moreover, during the post weaning period, the effect of dietary treatments on jejunal glutathione status showed that DL-HMTBA treatment allowed a better red-ox status than in the other treatments (as shown by higher reduced glutathione and lower oxidised glutathione to reduced glutathione ratio).

此外，DL-HMTBA組的小豬有更好的腸道形態(tài)，具有較高的絨毛高度和絨毛高度/隱窩深度比，從而使得它們擁有更好的吸收能力。

Higher feed intake

Another interesting finding was that weaned piglets receiving the DL-HMTBA source of methionine in their complete feed, show a higher feed intake across post-weaning days (P<0.05) compared to those in the control or dl-methionine groups, leading to a better average daily weight gain.

更高的采食量

另一個(gè)有趣的發(fā)現(xiàn)是，與對(duì)照組和DL-蛋氨酸組相比，DL-HMTBA組的斷奶仔豬在斷奶后采食量更高(P <0.05)，因此DL-HMTBA組的平均增重也較高。

The researchers also concluded that increased consumption of methionine as DL-HMTBA might alleviate stresses associated with early weaning. Compared to the control group, higher villus height, villus height/crypt depth ratio and number of goblet cells were observed in the DL-HMTBA treatment group providing evidence for its positive effect on weaning stress.

研究人員還得出結(jié)論，增加DL-HMTBA形式的蛋氨酸補(bǔ)充可以緩解斷奶早期的應(yīng)激反應(yīng)。與對(duì)照組相比，在DL-HMTBA組中觀察到更高的絨毛高度及絨毛高度/隱窩深度比和杯狀細(xì)胞數(shù)，這也證實(shí)了為何DL-HMTBA組能更好的克服斷奶應(yīng)激。

The team at Sichuan Agricultural University concluded that early-weaning induced growth retardation appears to be attenuated through changes in plasma amino acid profiles and elevation of growth performance and intestinal antioxidant capacity in piglets, following increased consumption of methionine as DL-HMTBA.These observations offer novel insights into the mechanism of sulphur amino acids metabolism, with important nutrition and health implications.

四川農(nóng)業(yè)大學(xué)的研究小組得出結(jié)論，斷奶早期造成的發(fā)育遲緩似乎可通過改變血漿中氨基酸的構(gòu)型得到改善。仔豬的生長(zhǎng)性能及腸道抗氧化能力隨DL-HMTBA形式蛋氨酸消耗的增加而提高。這些發(fā)現(xiàn)為含硫氨酸代謝機(jī)制提供了新的見解，對(duì)營(yíng)養(yǎng)和健康的研究具有重要意義。