During the last decades, the genetic improvement of the suidae has allowed an upward growth in the size of the litters (hyperprolific lines) but at the same time an increase in the mortality of the piglets has been observed, which can oscillate between 4-20% in the first 3 or 4 days of life and during the weaning phase.

Lactation and weaning are considered especially susceptible stages during the productive life of pigs and it is important to recognize which agents or factors could be increasing mortality on the farm.

Causes of mortality in lactating and weaned piglets

The causes of mortality that affect lactating and weaned piglets are very diverse. Many of the causes are directly related to the sow and the milk it produces in this first part of the cycle. If the sows show deficiencies in their state of health or in the production of quality colostrum, the piglets may be compromised in their immunological development and may not grow optimally from the beginning, lengthening their productive cycle, or in the worst cases, increasing the mortality rates and decreasing the profitability of production.

Colostrum, the first milk produced by the sow after farrowing, contains a high concentration of antibodies and other immunological components that help protect lactating pigs from disease. If the colostrum is of poor quality, is insufficient or is not consumed in the first hours of life, pigs can experience an immune deficiency that leaves them more susceptible to infections and diseases.

In addition to the transfer of passive immunity, nutrition plays a crucial role in the health of lactating and weanling pigs. During this stage, pigs experience significant changes in their intestinal microbiota, which is essential for the development and proper functioning of the immune system. An inadequate diet can negatively affect intestinal well-being, altering the balance of the microbiota and weakening the body’s defenses.

Vulnerable pigs are more prone to disease, which can require costly treatments and affect production performance. In addition, infections and enteric diseases can lead to decreased nutrient uptake, resulting in poor growth and reduced feed conversion efficiency.

The highest mortality rates in this phase are related to enteric disorders and diseases. The pathologies that we frequently find in farms are:

1. Neonatal colibacillosis:

   It is one of the most relevant enteric pathologies at these stages, produced by Escherichia coli.
   Colibacillosis in lactating and weaned pigs occurs when proper nutrition and management control is not maintained. E. coli bacteria are naturally abundant in the healthy intestine of pigs. What happens is that when the conditions of the intestine are not optimal due to dysbiosis, poor development of the intestine and immune deficiencies due to problems with the intake of colostrum or its composition, this bacterium can proliferate more easily, which leads to the appearance of this pathology.

   On the other hand, it is a bacterium that has various strains, including enterotoxigenic ones. These strains produce fimbriae that adhere to the surface of the intestinal epithelium and also produce enterotoxins that induce fluid leakage from the epithelium into the intestinal lumen. When it gets complicated, enterotoxins enter the bloodstream and septicemia, acute diarrhea and severe dehydration occur. In most cases it causes the death of the piglet due to the severe symptoms it presents.

2. Clostridiosis:

   It is a disease produced by Clostridium perfringens type A and C, it appears in neonates or piglets with 4-6 days of life when they stop taking colostrum.
   Clostridium perfringens type A causes necrotic enterocolitis. The bacterium produces alphatoxin which is hemolytic, necrotizing and lethal with mortality of up to 50% and betatoxin which produces necrotic enteritis as well as involvement of the central nervous system in severe cases.
   Clostridium perfringens type C causes the typical acute dysentery, which presents with nervous disorders, diarrhea and necrosis of the intestinal mucosa. Many times, the symptoms are so severe that no treatment is effective and the death of the piglets is inevitable.

3. Porcine rotavirus:

   It is the most important viral disease in suckling piglets. It affects the intestinal villi, mainly the jejunum and ileum, and is accompanied by anorexia, vomiting, foul-smelling diarrhea, and dehydration, with 50% mortality in piglets under three weeks of age.

4. Intestinal parasites:

   The main parasitic agents are Isospora suis, Ascaris, Hyostrogylus, Trichuris suis, among others. They are pathogens that cause inflammatory lesions in the intestine and produce disorders such as diarrhea, enteritis, dehydration, weight loss, and growth retardation. In the case of Isospora suis, it causes lesions in the enterocytes and atrophy of the intestinal villi, which leads to persistent diarrhea and malabsorption of the nutrients present in the feed. This fact is of great importance since the subsequent stages of production will be affected, such as fattening, a phase where the weight increase must be exponential through the correct assimilation of nutrients.

Prevention of enteric pathologies

A serious mistake when managing these pathologies is to implement only a symptomatic and/or pharmacological treatment, this is mainly due to the fact that in many cases the primary cause is not being solved and this generates recurrences of the pathologies in question.

The prevention of enteric pathologies in lactating and weaned pigs implies a comprehensive approach that includes proper breeding management, balanced nutrition, stress management, intestinal microbiota control, and the implementation of vaccination programs. By adopting these preventive measures, the incidence of intestinal diseases can be significantly reduced, and the welfare and performance of pigs improved at this critical stage of their lives.

Effective strategy to reduce the prevalence of enteric diseases and ultimately mortality in lactating and weaned piglets

Fortunately, there are technologies developed specifically for the improvement of mortality in lactating and weaned piglets. A clear example is Alquernat Nebsui, an intestinal conditioner made up of pronutrients of plant origin, which stimulates the regeneration and proper functioning of enterocytes by stimulating specific genes that optimize the functions of these intestinal cells.

Alquernat Nebsui was tested in vivo in piglets to assess its efficacy in reducing mortality during lactation. The trial consisted of supplementing 1 ml of Alquernat Nebsui orally to 38 piglets on day 2 of life, comparing it with a control group of 33 piglets without any supplementation; both groups also received a standard basal diet. The results showed that Alquernat Nebsui produced a significant improvement in parameters such as:

• The average weight of the piglets (+0.22kg at 21 days of the productive cycle)

• Average daily gain (ADG) (+ 3 g/d which translates into +1.5% weight gain)

• Better mortality (-13,22%)

Alquernat Nebsui achieves an improvement in productive parameters such as weight (+0.22 kg/pig), ADG (+3g/d) and mortality (-13.22%) by stimulating enterocyte regeneration and physiology. This translates into improved feed digestion, nutrient absorption, and control of pathogenic flora in the intestine, improving intestinal well-being, which allows optimal performance of the piglets. In addition, since it is a natural product, it does not generate antimicrobial resistance or residues and does not require a period of suppression.

On the other hand, regarding the weaning and post-weaning phase where diarrhea is common, there are products on the market, such as zinc oxide (ZnO), used to reduce the severity of enteric pathologies and promote the growth of piglets. However, it has an extremely serious problem associated, which is the generation of waste that leads to the contamination of groundwater, surface and sedimentary water. This fact has promoted that its use has also been progressively prohibited in EU countries and other parts of the world.

Alquernat Nebsui was tested in vivo against zinc oxide in piglets. The trial was based on the supplementation of two groups, the control with zinc oxide at 2 kg/t and the other group with Alquenat Nebsui at 0.5kg/t for 30 days. The results that Nebsui obtained in comparison with Zinc oxide were important:

• A. Nebsui achieved an improvement of 1.7% in live weight

• A. Nebsui achieved an improvement in average daily gain of 17%

• Achieved a higher consumption which is related to a lower prevalence of diarrhea at an early age.

An improvement in the structure of the intestinal mucosa was also observed at the histological level:

These results show that Alquernat Nebsui achieves less morbidity since there are -42% of piglets with diarrhea and less severity compared to the results obtained with zinc oxide. It also achieves greater digestive efficiency because, as observed at the histological level, a better state of the villi is generated.

Conclusions

Mortality is a parameter that needs to be exhaustively controlled in pig farming due to its direct relationship with the economic benefit of the farm. The management of the nutrition and health of the sows is crucial for the correct production of colostrum and, above all, for the correct transfer of the immunity of the piglets to obtain immunocompetent pigs and prevent enteric diseases such as colibacillosis, coccidiosis, etc., promoting the welfare of pigs during the lactation and weaning phases.

For that matter, the use of Alquernat Nebsui has proven to be effective in reducing mortality and improving productive parameters. Compared to zinc oxide, Alquernat Nebsui has shown superior results in terms of weight, average daily gain, and intestinal well-being of piglets.

In summary, Alquernat Nebsui is positioned as a promising solution to prevent enteric diseases and improve the performance of lactating and weanling pigs.

Bibliography

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