The standard of weaning pigs at 21 days coincides with a low point in the development of a pig’s immune system. The pig is “immunodeficient” or susceptible to illness during this time.
 
In the first weeks of life, the pig’s immunity is strong because he absorbs antibodies from the sow’s colostrum and milk. This passive immunity peaks at day 7 and declines as the pig ages. (See figure 1)
 
As the pig approaches weaning, his immune system starts to produce antibodies in response to bacteria, viruses or toxins in the environment. However, the weaned pig’s immunity continues to come mostly from the sow’s antibodies until he is nearly 28 days old – past the standard weaning age. He will not be fully covered by his own active immune system until day 42 or later.

Pig digestive system is key to support pig health

One way to support the immunodeficient nursery pig is to protect and support the pig’s digestive system health. Why do you want to protect the gut? Because it has two important functions:
 

• The pig digestive system contains 70 percent of the lymphoid tissue that makes up a pig’s immune system.
• To act as a barrier between the pig’s digestive system and the rest of the body.

Many pathogens enter the body through the digestive system, and a healthy gut lining keeps undesirable bacteria and toxins inside the intestine, where they can pass through the pig without causing harm. If this barrier is disrupted, an influx of bacteria or other antigens can open the door to inflammation or illness.

How to support weaned pig digestive system health

Adequate feed and water intake are the key to maintaining the barrier, and the right nursery diet can support both feed and water intake.

• Choose nursery feeds such as UltraCare^® starters with intake-enhancing ingredients that trigger feeding behavior. These feeds encourage initial and repeat pig feed intake.
• Choose a feed such as UltraCare^® starters with complex rather than simple ingredients. Complex diets include protein sources that are easily digested by the young pig’s immature digestive system, preventing digestive irritation or stress.
• Supplement the early nursery diet with UltraCare^® gel, which supplies a water component as well as nutrients and electrolytes.

Weaning is the most stressful period for a young pig, and it happens at a time when immunity from sow’s milk is declining and the pig’s immune system is not fully developed. The right nutrition in this phase supports optimal gut development and a strong intestinal barrier against pathogens.
 
How would improved ROI impact your operation? Learn more about our swine nutrition technology and connect with your local Purina representative to learn more.