Scours, commonly known as diarrhea in swine, is a symptom of an underlying disruption within the pig’s gastrointestinal tract, not a disease itself. It has a high incidence rate, particularly in young piglets where it is known as neonatal scours, and carries the potential for rapid mortality. The loss of fluids and electrolytes associated with scours can quickly lead to death from dehydration and hypovolemic shock. Understanding the identification, causes, and management of scours is necessary for maintaining herd health and minimizing losses.
Recognizing the Signs
The first indication of scours is a noticeable change in the pig’s fecal matter, moving from a firm consistency to loose, watery, or thin feces. The color of the manure can vary significantly depending on the cause, often appearing yellow, white, or gray. In severe cases, it may contain flecks of blood or mucus.
Fecal staining around the perineum, tail, and hindquarters is a clear visual sign of diarrhea. Affected pigs also display behavioral and physical symptoms signaling a serious health decline, including lethargy, weakness, and a rough, dull hair coat.
The most immediate life-threatening consequence is dehydration, manifesting physically as sunken eyes and inelastic skin. Affected piglets often huddle together, shiver, and seek supplemental heat due to an inability to regulate their body temperature, indicating compromised energy status.
Primary Causes and Contributing Factors
The causes of scours are complex, often involving a combination of infectious agents, environmental stressors, and nutritional imbalances that disrupt the pig’s gut health. The gastrointestinal system’s malfunction results from the gut either failing to digest and absorb nutrients or actively secreting excess fluid due to toxin production.
Infectious Agents
Infectious agents are a major category of scours causes, with specific pathogens targeting different age groups. Pathogenic strains of E. coli are a common cause, frequently striking piglets within the first week of life. They produce toxins that cause a profuse, watery scour and rapid dehydration.
Other bacteria, such as Clostridium difficile and Clostridium perfringens, cause enteritis and acute scouring, typically within the first week after birth. Viral causes like Rotavirus often affect pigs between three and six weeks of age by damaging the intestinal lining, which reduces the surface area for absorption.
Highly contagious viruses such as Transmissible Gastroenteritis (TGE) and Porcine Epidemic Diarrhea (PED) can cause explosive outbreaks involving vomiting and severe diarrhea in all ages, but they are particularly devastating to piglets under three weeks old. Parasitic causes, primarily Coccidia, tend to induce a creamy or yellowish scour in piglets between nine days of age and weaning.
Non-Infectious and Environmental Factors
Environmental factors significantly contribute to the onset and severity of scours by increasing stress and weakening immunity. Chilling, often caused by inadequate supplemental heat or drafts, diverts the piglet’s energy away from immune function and growth toward maintaining body temperature.
Poor sanitation allows for a high pathogen load, overwhelming the piglet’s limited defenses. Overcrowding and the stress of mixing pigs at weaning also suppress the immune system, making the animals highly susceptible to opportunistic bacterial proliferation.
Nutritional Factors
Nutritional causes are particularly relevant during transition periods, such as around weaning. The sudden shift from a highly digestible milk diet to a solid, plant-based feed can lead to undigested food accumulating in the gut. This undigested material provides a perfect substrate for pathogenic bacteria, especially E. coli, to multiply.
Milk replacer intolerance or poor diet quality can also trigger digestive upset. Issues with the sow, such as mastitis or agalactia (failure to secrete milk), can reduce the piglet’s intake of protective antibodies and nutrients, predisposing the litter to infectious scours.
Treatment and Supportive Care
The immediate intervention for a scouring pig focuses on counteracting the severe dehydration that is the primary cause of mortality. Supportive care must be implemented quickly, regardless of the suspected cause, to stabilize the animal’s fluid and energy levels.
Supportive Care
Rehydration is paramount and involves administering oral electrolyte solutions to replace lost fluids and salts. These solutions must be kept clean and fresh, often requiring active administration by syringe to severely affected, weak piglets.
Maintaining a warm, dry environment is equally important to prevent chilling, which exacerbates energy loss. Providing supplemental heat and ensuring dry bedding helps the piglet conserve energy, allowing its body to focus on fighting the infection and recovering.
Medical Intervention
Medical treatment depends on accurately identifying the causative agent, which typically requires a veterinarian to perform diagnostic tests on fecal samples. For confirmed bacterial infections, such as those caused by E. coli, appropriate antibiotics may be prescribed to reduce the pathogen load.
Antibiotic use should be guided by sensitivity testing to ensure the correct drug is used, and it is usually administered orally for localized gut infections. However, antibiotics are ineffective against viral causes like Rotavirus or TGE, for which only supportive care can be provided.
Isolation of sick animals is necessary to contain the spread of the disease to healthy litters. Prompt veterinary consultation is required, as a specific diagnosis is needed to tailor the treatment plan, which may include anti-parasitic medications for Coccidia.
Long-Term Prevention Strategies
Long-term prevention relies on a comprehensive strategy targeting biosecurity, environmental control, and immunity enhancement to minimize pathogen challenge. Strict biosecurity protocols, including controlling human and vehicle traffic, prevent the introduction of new disease strains onto the farm.
Sanitation practices are a major component of reducing the pathogen burden, especially in farrowing and nursery rooms. Implementing an “all-in/all-out” system, where rooms are completely emptied, cleaned, disinfected, and dried between groups of pigs, is highly effective.
Proper temperature management is necessary to reduce environmental stress on the piglets. This involves creating a warm microclimate for the piglets while keeping the sow cooler, achieved through supplemental heat lamps and ventilation systems that control air flow and humidity.
Vaccination programs bolster herd immunity against specific pathogens like E. coli and Clostridium. Sows are often vaccinated prior to farrowing to stimulate high levels of antibodies in their colostrum and milk, providing passive protection to the nursing piglets.
Ensuring that every newborn piglet receives sufficient colostrum within the first hours of life is the most effective way to protect it from early-life scours. Management practices like split-suckling help ensure smaller or weaker piglets receive adequate maternal antibodies before the gut’s ability to absorb them declines.