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在养猪生产过程中，断奶仔猪腹泻的问题相当普遍。据调查，断奶仔猪腹泻率在20%-30%左右。一般情况下，断奶后3-5天的腹泻率为0.6％；而8-13天腹泻就变得严重，腹泻率达32%左右。该病造成的死亡率可达10%-20%，即使病愈，其生长发育也会受到严重影响，推迟出栏时间，给养殖户带来巨大的经济损失。
引起仔猪腹泻的原因非常复杂，主要有：①致病性大肠杆菌引起的腹泻；②仔猪断奶后，母源抗体急剧下降，造成抵抗力下降；③仔猪的消化机能不健全，高植物蛋白的饲料引起胃肠道机能紊乱；④断奶后的应激，尤其是环境应激，如温差超过10℃时，腹泻率就会增加25％－30％，湿度过高也会增加腹泻的次数；⑤饲喂方式不当，如过度限饲或过度饲喂会引起饥饿性和过食性腹泻；⑥肠道发生的免疫反应。仔猪断奶后即切断了从母体获得被动免疫的来源，但由于主动免疫，尤其是特异性免疫系统功能还未完全有效地建立起来，IgA＋B细胞占主要地位要在4周龄时才能达到成年猪水平，而IgM＋细胞要到3－4月龄才达到成年猪水平。一旦开始饲喂含有大量植物蛋白的玉米—豆粕型日粮，断奶仔猪就会发生肠道免疫反应，出现腹泻现象。
研究表明，在引起仔猪腹泻的诸多因素中，原发性因素并不是大肠杆菌，而是由于断奶过程中的应激(尤其是采食了大量的植物蛋白这类的抗原)影响肠道和粘膜免疫系统的改变，小肠绒毛变短，微生态平衡打破。造成了肠道的损伤，使胃肠酶水平和吸收能力下降。新生仔猪肠道有一种“记忆”细胞，它能识别抗原并与之反应，当断奶仔猪接触到从来没有接触过的植物蛋白时，就会发生免疫反应，以消除抗原的危害。但是，当断奶仔猪长期接触这些日粮中的抗原，日粮的抗原物质达到一定量或作用时间后，仔猪就会产生免疫耐受力，从此对这种抗原不再反应。在仔猪没有适应日粮中的抗原或者肠道未产生免疫耐力之前，这种日粮仍会引起仔猪腹泻。
由此可见，控制仔猪的腹泻应该从仔猪营养方面着手，以下是几点控制仔猪腹泻的措施。
一、选择优质饲料原料
猪乳是高度可消化养分的优良来源。按干物质计，猪乳中含脂肪45％、乳糖25％、蛋白28％，其余成分包括免疫球蛋白、维生素和矿物质。但是绝大部分断奶日粮含脂肪太低(常低于10％)，含碳水化合物(淀粉)较高，以及高含量的植物蛋白质。猪乳与断奶日粮养分上的差异，可能是造成仔猪断奶后腹泻的主要原因之一。因此，在断奶仔猪日粮中应选择优质饲料原料。
二、早期补料
养猪生产者都知道，要想培育出最好的仔猪，必须使用最好的仔猪颗粒料，早期补料。因为用好的仔猪料补料不仅会影响断奶阶段，而且通过其后效作用影响猪的整个一生。研究表明，在仔猪出生5－7天开始补料，可影响断奶仔猪对蛋白质的反应，使免疫系统产生免疫耐受力，促进胃肠道的发育，减少肠道对日粮蛋白的过敏反应，因此，抓好断奶前补料可以预防腹泻的发生。
三、降低饲料中的蛋白质水平
仔猪断奶后，腹泻的发生率随着猪日粮中蛋白质含量的提高而增高，因为蛋白质是主要抗原物质，降低蛋白质水平，可减轻肠道的免疫反应和腹泻程度。
四、饲喂添加剂
1、添加柠檬酸
由于仔猪消化机能不健全，其胃底腺不发达，缺乏产生足够的胃酸能力。断奶前，胃内的酸性环境主要靠母乳中乳糖发酵产生乳酸维持。这样分泌的胃酸不足会造成胃蛋白酶原的激活受到限制，因此，在玉米—豆粕型日粮中，胃对鱼粉、豆粕等非乳蛋白不能很好地消化，造成小肠内细菌增殖，肠道功能紊乱，腹泻脱水。在饮水和饲料中添加1％的柠檬酸可降低胃内的pH值，保持一定的酸度，可以激活消化酶，有利于乳酸杆菌的繁殖，提高消化能力，从而改善仔猪的增重速度和饲料利用率。
2、添加酶制剂
在日粮中添加稳定性、特异性的外源消化酶(脂肪酶和淀粉酶)对仔猪性能有较大的影响，它可以弥补断奶后仔猪体内酶的分泌不足，从而提高饲料的利用率，防止消化不良性腹泻。
3、添加益生素
益生素是从畜禽肠道内的正常菌群中分离培养得出的有益菌种，在肠道内繁殖成优质菌群，抑制病原菌及有害微生物的生长繁殖，形成肠道内良性微生态环境。从而减少仔猪腹泻，改善肠道健康，促进营养物质的消化吸收，增强机体抗病能力，有利于断奶仔猪的生长发育。
4、添加抗生素
抗生素可促进生长和改善饲料转化率已被广大养殖户所接受。在补料和开食料中添加抗生素，既可控制病原微生物增殖，又可加速肠道免疫耐受过程，从而减轻肠道损伤，预防腹泻的发生。但目前用于防止仔猪腹泻的抗生素如金霉素、泰乐菌素、杆菌肽锌、喹乙醇等持续使用使病原菌产生耐药性，并在畜禽产品中残留给人体健康带来危害，已遭到无抗品的抵制。
5、高锌
在日粮中添加高锌可以提高采食量和饲料利用率，并能有效地预防腹泻的发生。大量研究表明：高锌3000mg 能有效减少断奶仔猪腹泻的发生，但高锌对仔猪生长发育造成危害：高锌首先打破原有各种元素的平衡，造成仔猪对铜、铁的吸收不利，可导致铁、铜继发性缺乏，出现贫血，高锌大部分随粪便排泄到环境中，造成环境污染。目前几乎所有饲料厂家均在寻找和试用高锌的替代产品，如纳米蒙脱石、复合益生素、益生元、中草药饲料添加剂等。
6、纳米蒙脱石
纳米蒙脱石是新兴起的抗腹泻和脱霉的饲料添加剂，对消化道内的霉菌毒素、病毒、病菌及其产生的毒素有固定、吸附作用；对消化道粘膜有覆盖能力，提高粘膜屏障对攻击因子的防御功能；还可脱出饲料中霉菌毒素，提高饲料的品质。纳米蒙脱石中含有硒等微量元素，可以弥补微量元素的不足，对畜禽的生长有促进作用。非常安全，无休药期，无毒副作用，不产生抗药性。纳米蒙脱石治疗仔猪腹泻的临床效果观察表明，纳米蒙脱石可替代抗生素和高锌，是无抗首选添加剂。
预防断奶仔猪腹泻，除了通过上述几点控制措施来保证营养的均衡，还与仔猪的管理水平(如舍温、喂量、喂法、适宜断奶等)、环境等有一定关系。控制仔猪腹泻，应采取综合防制措施：预防为主，防治结合，少用或不用抗生素，减少高锌的危害，走无抗的健康道路。
The English version
In the process of pig production, weaning diarrhea piglets problem is quite common. According to the survey, weaned piglets diarrhea rate from 20% to about 20%. In general, 3 to 5 days after weaning diarrhea rate was 0.6%; And 8 to 13 days becomes severe diarrhea, diarrhea rate was 32%. The disease caused by the mortality rate of up to 10% - 10%, even if the recovery, its growth and development will be severely affected, delay output, give farmers bring huge economic losses.
The cause of diarrhea piglets is very complex, mainly include: (1) caused by pathogenic e. coli diarrhea; (2) the piglets after weaning, a sharp drop in maternal antibody, resulting in decreased resistance; (3) piglets digestive function is not sound, the high plant protein feed causes gastrointestinal disorders; (4) after weaning of stress, especially the environmental stress, such as the temperature difference of more than 10 ℃, the diarrhea rate can increase 25% 30%, high humidity can also increase the number of diarrhea; (5) the improper feeding, such as excessive limit feeding or excessive feeding may cause sexual hunger and trophic diarrhea; 6. The intestinal immune reaction. Piglets weaned after cutting off the source of the passive immunity from the mother, but as a result of active immunization, especially the specific immune system function has not been fully set up effectively, IgA + B cells dominate in 4 weeks to reach into the swine, and IgM + cells until 3 or 4 months into swine. Once you start feeding type contains a lot of vegetable protein of corn, soybean meal diet, weaned piglets intestinal immune response occurs, diarrhea.
Studies have shown that in a number of factors causing diarrhea piglets, the primary factor is not e. coli, but due to the stress in the process of weaning feed (especially a large number of this kind of plant protein antigen) affect the intestinal mucosal immunity and system changes, small intestinal villus shorten, micro ecological balance. Caused the damage of the gut, decreased gastric enzyme level and absorptive capacity. Have a "memory" newborn piglets intestinal cells, it can identify antigen and reaction, when weaned piglets contact to never contact the plant protein, the immune response, occurs in order to eliminate the dangers of antigen. But when weaned piglets long-term exposure to the antigen in the diet, diet material reaches a certain amount or duration of antigens, piglets will generate immune tolerance, from the response to the antigens is no longer. In the piglet did not adapt to the diet of antigen or intestinal immune endurance before, this kind of diet will cause diarrhea piglets.
Thus, the piglets nutrition control of piglet diarrhea should begin, here are some measures to control the diarrhea piglets.
A, choose high quality feed ingredients
The pig milk is a good source of highly digestible nutrients. According to the meter of dry matter, the pig fat in milk 45%, lactose 25%, protein 28%, the rest of the ingredients including immune globulin, vitamins and minerals. But the vast majority of weaning diet fat too low (usually less than 10%), with high carbohydrates (starch), and high content of plant protein. Pig milk nutrients and weaning diet differences, may be one of the main cause of piglets after weaning diarrhea. Therefore, in the weaned piglets diet should choose high quality feed ingredients.
Second, the early filling material
Producers know that if you want to breed the best piglets, must use the best piglet grain, early filling material. Because with a good piglet fill material will not only influences the stage of weaning, and through its aftereffect effect influence the pig's whole life. Research shows that in piglets born 5-7 days began to fill material, can affect the weaned piglets on the reaction of the protein, the immune system to produce the immune tolerance, promote the development of the gastrointestinal tract, reducing intestinal allergic reaction to the diet protein, therefore, pays special attention to the filling material can prevent the occurrence of diarrhea before weaning.
Three, to reduce the level of protein in the feed
The incidence of diarrhea piglets after weaning, as it increased with the increase of protein content in pig diet, because protein is the major antigen, lower levels of protein, can reduce the degree of immune response and diarrhea.
Fourth, feeding additives
1, add citric acid
Due to the piglets digestive function is not sound, the fundic gland is not developed, the lack of produce enough ability of gastric acid. Before weaning, stomach acid environment mainly by breast milk lactose fermentation to produce lactic acid. So inadequate secretion of stomach acid can cause the activation of pepsinogen is restricted, therefore, in the corn, soybean meal type diet, stomach to fish meal, soybean meal and other non dairy protein can't digest well, cause intestinal bacteria proliferation, intestinal disorders, diarrhea dehydration. 1% of citric acid is added in the water and feed can reduce the pH of the stomach, maintain acidity, can activate digestive enzymes, promotes the breeding of lactic acid bacteria, improve digestion ability, thus improve the speed of weight gain and feed utilization rate of piglets.
2, add enzymes
Stability, specificity is added in the diet of exogenous enzymes, lipase and amylase) has a great influence the performance of piglets, it can make up after weaning piglets in enzyme secretion insufficiency, so as to improve the utilization rate of feed and prevent the digestion is not benign diarrhea.
3, add probiotic
Probiotic from livestock and poultry cultivation in the normal intestinal flora of beneficial bacteria in the intestines to high-quality bacteria, inhibit the growth of pathogenic bacteria and harmful microbes breeding, form a benign intestinal micro ecology environment. To reduce diarrhea piglets, the intestines, promote digestion and absorption of nutrients, enhance airframe disease-resistant ability, is conducive to the growth and development of weaned piglets.
4, add antibiotics
Antibiotics can promote growth and improve the feed conversion rate has been accepted by the broad masses of farmers. Food in the filling material and adding antibiotics, can control the pathogenic microorganism proliferation, but also accelerate the process of intestinal immune tolerance, so as to reduce the damage, prevent the happening of the diarrhea. But currently used in preventing diarrhea piglets antibiotics such as chlortetracycline, tylosin, bacitracin zinc, olaquindox, such as continuous use make the pathogen resistance, and residue in livestock and poultry products has a harmful effect on human health, has been rejected by no resistance to product.
5, high zinc
High zinc is added in the diet can increase feed intake and feed efficiency, and can effectively prevent the happening of the diarrhea. A large number of studies have shown that: high zinc 3000 mg can effectively reducing the occurrence of weaning diarrhea piglets, but high zinc cause harm to the piglet growth: high zinc first break the balance of various elements, original caused piglet is adverse to the absorption of copper, iron, which can lead to the lack of iron, copper, secondary anemia, most high zinc with manure to the environment, cause environmental pollution. Now almost all feed manufacturers are looking for and trial of high zinc alternatives, such as nanometer montmorillonite, compound probiotics and prebiotics, Chinese herbal medicine feed additive, etc.
6, nanometer montmorillonite
Nanometer montmorillonite is the rise of new anti diarrhea and mildew of feed additives, to mold toxins, viruses, bacteria in the digestive tract and produce toxins are fixed, adsorption; On the digestive tract mucous membrane covering ability, to improve the defence function of mucous membrane barrier to attack factor; Still can emerge mycotoxins in feed, improve the quality of the feed. Nanometer montmorillonite stone containing trace elements like selenium, can make up for the lack of trace elements, has promoting effect to the growth of livestock and poultry. Very safe, "without medicine, non-toxic side effects, no resistance. Nanometer montmorillonite in the treatment of diarrhea piglets clinical effect observation showed that nanometer montmorillonite alternative antibiotics and high zinc, is no preferred resistant agent.
Prevention weaning diarrhea piglets, in addition to the above several control measures to ensure that the balance of nutrition, also with the piglets management level (e.g., Sherwin, feed, feed method, suitable for weaning, etc.), environment and so on. Control diarrhea piglets, comprehensive control measures should be taken: prevention first and combining prevention and cure, with little or no antibiotics, reducing the harm of high zinc, no resistance to the health of the road.
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