Common Pig Health Problems: Diseases, Symptoms, Treatment & Swine Vet Care

Introduction: Why Pig Health Management Matters

Whether you raise a handful of backyard pigs or manage a large commercial swine operation, understanding common pig health problems is one of the most important skills you can develop. Swine are intelligent, resilient animals—but they are also susceptible to a wide range of infectious diseases, parasites, and environmental health challenges that can spread rapidly through a herd.

In commercial production, a single disease outbreak can cost tens of thousands of dollars in treatment costs, production losses, and mortality. For backyard producers, a sick pig can be emotionally devastating and financially significant. In both cases, early recognition of disease signs and swift access to a qualified swine veterinarian are critical to limiting damage and protecting your investment.

This comprehensive guide covers the most important swine diseases you need to know—from respiratory and reproductive problems to viral pandemics and external parasites. We'll walk through symptoms, treatment options, vaccination protocols, and biosecurity strategies that every pig producer should have in place. We'll also explain when to call your vet and how to find a large animal veterinarian with swine expertise in your area.

Understanding Pig Physiology and Why Swine Get Sick

Before diving into specific diseases, it helps to understand a few things about pig biology that make them particularly susceptible to health problems.

Respiratory Anatomy

Pigs have relatively small lung capacity for their body weight, and they are obligate nose-breathers. This means that any respiratory disease—whether bacterial, viral, or caused by poor ventilation—can rapidly become life-threatening. Ammonia buildup from manure in poorly ventilated buildings is a major contributor to respiratory disease in both commercial and backyard settings.

Social Structure and Stress

Pigs are highly social animals, and the stress of mixing pigs from different groups, overcrowding, weaning, or transport weakens their immune systems and makes them significantly more vulnerable to infectious disease. The concept of "all-in, all-out" production—where buildings are completely depopulated and disinfected between groups—was developed specifically because of how stress and pathogen buildup interact in swine.

Rapid Disease Spread

Most swine pathogens spread rapidly through direct pig-to-pig contact, contaminated equipment, aerosols, fomites (boots, clothing, vehicles), and in some cases, through the air over significant distances. This is why biosecurity—controlling what comes onto your farm—is the foundation of swine health management.

Major Viral Diseases in Swine

1. Porcine Reproductive and Respiratory Syndrome (PRRS)

PRRS is arguably the most economically damaging swine disease in the United States and much of the world. It costs the U.S. pork industry an estimated $664 million per year. First identified in the late 1980s, PRRS is caused by a single-stranded RNA arterivirus that exists in two major strains (North American and European) and continuously mutates, making control extremely challenging.

How PRRS Spreads

• Direct contact between infected and susceptible pigs
• Semen from infected boars (major route in breeding programs)
• Aerosol transmission—proven to occur over distances of several miles under certain weather conditions
• Contaminated equipment, vehicles, and personnel
• Transplacental transmission (from sow to fetus)

Symptoms in Sows and Gilts

• Abortions, mummified fetuses, stillbirths, and weak-born piglets
• Reduced farrowing rates and increased wean-to-estrus interval
• Mild respiratory signs (ear blueing, anorexia) in some animals
• Dramatic drops in farrowing rate (sometimes 30–50% in an acute outbreak)

Symptoms in Growing Pigs

• Respiratory distress, coughing, labored breathing
• Reduced growth rate and poor feed conversion
• Secondary bacterial infections (Streptococcus, Pasteurella, Haemophilus) dramatically worsen outcomes
• Increased mortality, especially in nursery pigs

Treatment and Control

There is no specific antiviral treatment for PRRS. Management focuses on:

• Vaccination: Modified live virus (MLV) vaccines are widely used but do not provide complete protection, especially against novel strains. Work with your vet to select the appropriate vaccine for your herd's exposure history.
• Exposure and stabilization: In some cases, controlled exposure of gilts before entering the breeding herd is used to stabilize PRRS status.
• Elimination programs: Large commercial operations sometimes undertake herd closure, mass vaccination, and eventual PRRS-negative status through testing protocols.
• Biosecurity: Air filtration systems, truck washes, and strict people movement protocols are increasingly common in high-risk areas.

2. Porcine Epidemic Diarrhea Virus (PEDv)

PEDv first emerged in the United States in 2013 and spread with devastating speed across the country. In its first two years, it killed an estimated 7 million piglets—a roughly 10% reduction in the U.S. pig inventory at the time. PEDv is caused by a coronavirus that attacks the intestinal lining, causing a profuse, watery diarrhea that is almost always fatal in piglets under two weeks of age.

Clinical Signs

• Neonatal piglets (0–14 days): Explosive watery yellow diarrhea, vomiting, rapid dehydration, near 100% mortality in naive herds
• Weaned pigs: Profuse diarrhea, vomiting, significant weight loss, mortality variable (10–30%)
• Adults: Diarrhea, anorexia, vomiting; rarely fatal but lose condition rapidly

Diagnosis

Fecal PCR testing is the gold standard. Submit fresh fecal samples or intestinal tissue from dead piglets to a veterinary diagnostic laboratory as quickly as possible. The speed of diagnosis is critical because PEDv moves through a barn at alarming speed.

Treatment

Treatment is entirely supportive—there is no antiviral treatment. For neonatal piglets, mortality in naive herds approaches 100% regardless of treatment. In weaned pigs, electrolyte therapy, keeping pigs warm and dry, and reducing feed density may help. The focus must shift immediately to:

• Stopping the spread within and between sites (strict biosecurity lockdown)
• Protecting gilts and sows: feedback protocols (controlled exposure to infected intestinal material) are sometimes used by veterinarians in commercial settings to accelerate immunity development in breeding females so they can pass maternal antibodies to piglets through colostrum
• Vaccination: USDA-conditionally licensed vaccines are available

How It Spreads

PEDv spreads primarily through fecal-oral contact. Even a tiny amount of contaminated feces on a boot, truck tire, or piece of equipment is enough to introduce the virus. Shared transport trucks are a major vector—thorough washing and disinfection of transport vehicles is essential.

3. Transmissible Gastroenteritis (TGE)

TGE is caused by a coronavirus related to PEDv and produces nearly identical clinical signs: explosive diarrhea and vomiting with near-100% mortality in piglets under two weeks of age. TGE was the original devastating swine enteric coronavirus before PEDv emerged and is still circulating in the U.S.

Differentiation between TGE and PEDv requires laboratory testing (PCR or immunofluorescence). Treatment and control approaches are similar. An important difference: TGE tends to be more seasonal, occurring primarily in winter months, while PEDv can strike year-round.

4. Porcine Circovirus Disease (PCVD / PCV2)

Porcine circovirus type 2 (PCV2) is one of the smallest known viruses that infects mammals, but it causes significant economic losses in swine production worldwide. PCV2 infection alone often causes mild or subclinical disease, but in combination with PRRS, parvovirus, or other immune stressors, it triggers a complex of conditions collectively called porcine circovirus-associated disease (PCVAD).

Clinical Syndromes

• Postweaning Multisystemic Wasting Syndrome (PMWS): The most recognized form. Affects 8–16 week old pigs. Progressive weight loss ("wasting"), enlarged lymph nodes, respiratory distress, diarrhea, jaundice in some animals. Mortality 5–20% but can be much higher.
• Porcine Dermatitis and Nephropathy Syndrome (PDNS): Red-purple skin lesions especially on hindquarters and perineum, kidney failure. Often fatal. Seen in growing and finishing pigs.
• Reproductive failure: PCV2 can cause late-term abortions, stillbirths, and mummified fetuses similar to PRRS.
• Porcine Respiratory Disease Complex (PRDC): PCV2 is frequently identified as a co-pathogen.

Vaccination

Highly effective PCV2 vaccines are available and are among the most important vaccines in swine production. Several commercial vaccines exist (Circumvent, Ingelvac CircoFLEX, Porcilis PCV, others). Most are administered to piglets at 3–4 weeks of age. Some protocols also vaccinate sows. Vaccination has dramatically reduced PCVAD losses in commercial herds since vaccines became available in 2006.

5. African Swine Fever (ASF) — Critical Biosecurity Threat

African Swine Fever (ASF) is currently the most serious threat facing the global swine industry. It has devastated pig populations across Asia, Europe, and parts of Africa. As of early 2026, ASF has NOT been confirmed in the United States commercial pig population, but it has been detected in wild boar in some Caribbean countries, and the risk of introduction to the U.S. through illegal pork products, infected wild boars at the border, or other pathways is considered significant by USDA APHIS.

What Is ASF?

ASF is caused by a large DNA virus in the Asfarviridae family—the only member of its family that infects vertebrates. It is unrelated to classical swine fever (hog cholera, which was eradicated from the U.S. in 1978). ASF is not a food safety concern for humans—it cannot infect people—but it is devastating to pigs, with mortality rates of 90–100% in susceptible herds with virulent strains.

Clinical Signs

• Acute form: High fever (104–108°F), loss of appetite, huddling, weakness, reddening/blueing of skin (ears, snout, legs), diarrhea (may be bloody), rapid death within 2–10 days. Pregnant sows abort. Sudden deaths with few prior signs.
• Subacute/chronic forms: Milder respiratory signs, weight loss, swollen joints, skin ulcers. Can persist in a herd for months, complicating detection.

What to Do If You Suspect ASF

ASF is a federally reportable foreign animal disease (FAD). If you see sudden, unexplained high mortality or severe illness in your pigs, you must:

1. Immediately isolate affected animals and restrict movement on and off your farm
2. Contact your veterinarian immediately
3. Contact your state veterinarian or USDA APHIS at 1-866-536-7593 (the FAD Emergency Hotline)
4. Do not move any pigs, products, or equipment off the farm until authorities clear it

There is currently no approved vaccine for ASF in the United States. Control relies entirely on biosecurity and rapid response. The economic consequences of an ASF introduction would be catastrophic for U.S. pork producers.

ASF Biosecurity Measures Every Producer Should Take Now

• Never feed untreated food scraps ("garbage feeding") to pigs—illegal in most states and a major ASF risk
• Never allow pigs to contact wild boars or feral hogs
• Do not bring pork products from ASF-affected countries onto your farm
• Report any suspicious illness immediately
• Know what ASF looks like—display USDA recognition materials in your barn

Major Bacterial Diseases in Swine

6. Erysipelas (Diamond Skin Disease)

Erysipelas is caused by the bacterium Erysipelothrix rhusiopathiae, which is ubiquitous in the environment and can survive for years in soil. Almost every pig farm has some level of exposure. The disease is most commonly seen in older growing pigs and breeding animals, and it tends to flare up during hot, humid weather or periods of stress.

Three Clinical Forms

• Acute/Septicemic: High fever (104–108°F), sudden death with few prior signs, reddened skin. Sows may abort. Often the first sign is finding dead pigs that appeared healthy the day before.
• Subacute/Skin (Diamond Skin Disease): The classic presentation—raised, firm, reddish-purple rhomboid (diamond-shaped) skin lesions most visible on lightly pigmented areas. Pigs may be febrile and lame. Lesions may progress to skin necrosis and sloughing.
• Chronic: Develops in recovered animals. Causes vegetative endocarditis (heart valve lesions leading to heart failure and sudden death) and/or arthritis in joints—particularly the hocks and carpals. Chronically affected pigs lose condition and eventually need to be culled.

Treatment and Prevention

Erysipelas responds very well to penicillin, which remains the treatment of choice. Early treatment of the acute form is usually curative. Chronic forms (arthritis, endocarditis) are much more difficult to reverse.

Vaccination is highly effective and is a standard part of swine health programs. Most sows and gilts are vaccinated twice per year. Boars should also be vaccinated. Growing pigs may be vaccinated in areas with high disease pressure. Multiple commercial vaccines are available (bacterins and modified-live).

Zoonotic risk: Erysipelothrix rhusiopathiae can infect humans, causing "erysipeloid"—a localized skin infection typically acquired through skin abrasions during pig handling. If you develop an unusual skin infection after working with pigs, tell your doctor.

7. Mycoplasma Hyopneumoniae (Enzootic Pneumonia)

Mycoplasma hyopneumoniae is the primary cause of enzootic pneumonia, the most common respiratory disease of swine worldwide. It causes a chronic, dry, non-productive cough that can persist for weeks to months. While Mycoplasma alone rarely kills pigs, it damages the respiratory epithelium and dramatically predisposes pigs to secondary bacterial infections (Pasteurella multocida, Actinobacillus pleuropneumoniae, Haemophilus parasuis) that can be fatal.

Signs

• Chronic, dry hacking cough—often most noticeable when pigs are disturbed or exercised
• Reduced growth rate (pigs may grow 10–15% more slowly than healthy pigs)
• Poor feed conversion
• Minimal fever in uncomplicated cases
• At slaughter: characteristic cranioventral consolidation of lungs (gray-purple firm areas in the front-bottom lobes)

Treatment

Several antibiotics are active against Mycoplasma including tiamulin, lincomycin, tetracyclines, and florfenicol. Treatment reduces clinical signs but does not eliminate the organism from the herd. Many commercial operations use strategic medication in feed or water during high-risk periods (weaning, mixing).

Vaccination

Mycoplasma vaccines (bacterins) are among the most widely used vaccines in commercial swine production. They significantly reduce lung lesion scores and improve growth performance. Most protocols involve vaccinating piglets at 1–3 weeks of age, often with a booster. Some one-dose products are also available.

8. Actinobacillus Pleuropneumoniae (APP)

APP causes pleuropneumonia—a severe, often rapidly fatal lung disease most commonly affecting pigs 10–16 weeks of age. It is characterized by fibrinous pleurisy (inflammation of the lung lining) and hemorrhagic pneumonia. Pigs may die within hours of showing the first signs.

Signs

• Sudden onset of fever (105–107°F), anorexia, depression
• Labored, open-mouth breathing; pigs reluctant to move
• Blood-stained foam from the nose and mouth
• Cyanosis (blue discoloration) of extremities
• Death within 24–48 hours in severe cases

Treatment

Penicillin, ampicillin, ceftiofur, florfenicol, and tulathromycin can be effective if given early enough. In acute outbreaks, individual injection of affected pigs plus mass medication of the group is typically required. Work with your vet for antibiotic selection based on sensitivity testing.

9. Streptococcus Suis

Streptococcus suis is carried in the tonsils of many clinically healthy pigs and causes disease when immunity is suppressed by stress, co-infection, or weaning. It is one of the most important causes of meningitis, septicemia, and sudden death in nursery pigs (3–8 weeks post-weaning).

Signs

• Meningitis form: Sudden onset—pigs found in lateral recumbency (on their side), paddling limbs, trembling, head tilt, loss of balance. Fever. Some pigs found dead.
• Septicemic form: High fever, depression, reddening of skin, sudden death
• Arthritis form: Hot, swollen joints; lameness

Treatment

Penicillin is the drug of choice. Early, aggressive treatment of meningitis cases with high doses of penicillin by injection can save some pigs, but survivors sometimes have permanent neurological deficits. Vaccination is available in some countries; in the U.S., autogenous bacterins are sometimes used in problem herds.

Zoonotic risk: Streptococcus suis is an important zoonotic disease, particularly in Asia. Human infections cause severe meningitis, septicemia, and permanent deafness. Use protective gloves and eye protection when handling sick pigs or pork products.

External Parasites: Mange and Lice

10. Sarcoptic Mange (Pig Mange)

Sarcoptic mange, caused by the mite Sarcoptes scabiei var. suis, is the most common and economically significant external parasite of swine. It is highly contagious and, once present in a herd, can be difficult to eliminate without a systematic treatment protocol. Mange mites burrow into the skin, causing intense itching and a characteristic skin condition.

Signs

• Hypersensitivity form (most common in growing pigs): Intense itching (pigs rub against pen walls and equipment constantly), red papules (bumps) progressing to crusty lesions, most prominent on the ears, flanks, and around eyes
• Chronic/crusted form (common in sows and boars): Thick, gray-brown crusts in the ear canal and on the face, neck, and legs. These chronically infected animals are the reservoir for the herd.
• Reduced growth rate and feed efficiency (estimated 5–12% reduction)

Diagnosis

Skin scrapings from fresh lesions (especially ear canal) examined under a microscope. Finding mites confirms the diagnosis, but false negatives are common—mange can be clinical even without finding mites on scraping.

Treatment

Injectable ivermectin or doramectin (both macrocyclic lactones) are highly effective. Pour-on formulations are also available. For herd elimination:

• Treat all animals in the herd twice, 14 days apart
• Treat incoming animals before introduction
• Clean and disinfect facilities (mange mites can survive off the host for several days)
• Repeat treatment of sows/gilts before farrowing

11. Pig Lice (Haematopinus suis)

Haematopinus suis is the largest louse of any mammal—easily visible to the naked eye. Louse infestations cause itching and skin irritation similar to mange, can transmit diseases (including porcine parvovirus), and can cause anemia in heavily infested young pigs. Lice are host-specific and cannot survive for long off the pig.

Signs

• Intense scratching and rubbing
• Visible lice (brownish, sesame-seed sized) and egg cases (nits) glued to hair at the base
• Most commonly found around the ears, neck, flanks, and inner legs

Treatment

The same macrocyclic lactone treatments used for mange (ivermectin, doramectin) are effective against lice. Two treatments 14 days apart are recommended to catch newly hatched nymphs.

Reproductive Problems in Swine

Porcine Parvovirus (PPV)

Porcine parvovirus is nearly ubiquitous in pig populations worldwide. In immune, previously exposed, or vaccinated sows, it causes no disease. In susceptible gilts and sows, however, PPV infection during early to mid-gestation causes embryo and fetal death, mummification, and reproductive failure. The classic presentation is small litter sizes with mummified fetuses of variable sizes (indicating deaths at different gestational ages).

Vaccination of gilts before their first breeding is essential and is one of the most cost-effective investments in swine reproductive management. Combination vaccines covering PPV, erysipelas, and leptospira are widely used.

Leptospirosis

Multiple serovars of Leptospira can cause reproductive failure in swine, including late-term abortions, stillbirths, and weak-born piglets. Leptospira are shed in urine and can persist in wet environments. Wildlife (particularly rodents and wildlife) serve as important reservoir hosts. Vaccination (multivalent bacterins) is standard in sow herds, combined with rodent control programs.

Swine Influenza (SIV)

Swine influenza virus (SIV) is endemic in U.S. swine herds and causes respiratory disease in all ages of pigs. Clinical signs include sudden onset of coughing, fever, nasal discharge, and lethargy. While rarely fatal on its own in non-naive herds, SIV significantly suppresses immunity and contributes to Porcine Respiratory Disease Complex (PRDC). Multiple H1 and H3 subtypes circulate. Vaccines are available but must be matched to current circulating strains—work with your vet and diagnostic lab for strain typing. SIV is a zoonotic concern—certain strains can infect people, so use respiratory protection when handling sick pigs.

Swine Vaccination Schedule

The following table provides a general framework. Your specific program should be designed in consultation with your swine veterinarian based on your herd's disease history, regional disease pressure, and risk factors.

Animal Category	Vaccine/Disease	Timing	Notes
Piglets 3–5 days	Clostridium perfringens types C & D	At birth	If sow not vaccinated; enteritis prevention
Piglets 3–4 weeks	PCV2 (Circovirus)	3–4 weeks of age	Core vaccine; single or 2-dose depending on product
Piglets 3–4 weeks	Mycoplasma hyopneumoniae	3–4 weeks; some products at 1 week	Booster per label if 2-dose product
Piglets 3–4 weeks	PRRS MLV	3–4 weeks; varies by herd status	Only in PRRS-positive herds; follow vet guidance
Pre-weaning	Haemophilus parasuis (Glasser's disease)	Per product label	High-risk nurseries
Gilts (pre-breeding)	Parvovirus + Erysipelas + Leptospira	5–6 weeks and 2–3 weeks before first breeding	Two-dose prime series; booster every 6 months
Gilts	PRRS MLV	30+ days before entering breeding herd	Herd-specific protocol
Gilts	Swine Influenza (SIV)	Per product; typically pre-breeding	Strain matching important
Sows	Parvovirus + Erysipelas + Leptospira	2–4 weeks pre-farrowing each parity	Boosts maternal immunity passed to piglets via colostrum
Sows	E. coli + Clostridium	3 and 5 weeks pre-farrowing	Prevents neonatal scours via passive immunity
Sows	Porcine Epidemic Diarrhea (PEDv)	Per label; conditionally licensed vaccines	Use in PEDv-positive herds or high-risk areas
Boars	Parvovirus + Erysipelas + Leptospira	Every 6 months	Erysipelas especially important—protects fertility
All breeding stock	Swine Influenza	Annually or semi-annually	Match to circulating strains

Always consult your swine veterinarian before implementing or modifying a vaccination program. Some vaccines require a valid Veterinarian-Client-Patient Relationship (VCPR) and a prescription.

Biosecurity: The Foundation of Pig Health

Biosecurity—the set of practices that prevent the introduction and spread of disease—is far more cost-effective than treating disease outbreaks. For both commercial operations and backyard producers, biosecurity should be a non-negotiable part of daily management.

Core Biosecurity Principles

External Biosecurity (Keeping Disease Out)

• Quarantine all new animals: Any new pigs brought onto your property should be isolated for a minimum of 21–30 days in a separate facility. Test for diseases relevant to your herd during this period. Never introduce pigs directly into your herd without quarantine.
• Source animals carefully: Know the health status of the farm you are purchasing from. Buy from reputable sources with documented health programs. Request health records and certificates.
• Control visitor access: Limit who enters your pig area. Require visitors to wear clean coveralls and boots provided by your farm. Keep a visitor log.
• Control vehicle access: Transport trucks are a major disease vector. Establish clean/dirty lines. Require trucks to be washed and disinfected before entering.
• No contact with other pigs or pig farms: If you have been on another pig farm, shower and change clothes before entering your own facility. Pathogens can survive on clothing and skin.
• Control feed and water inputs: Use secure, covered feeders and clean water sources. Prevent wildlife contamination of feed.
• Control wildlife and rodents: Feral pigs are a major ASF risk and carry multiple pathogens. Fence to prevent contact. Implement a rigorous rodent control program—rodents carry leptospira, E. coli, Salmonella, and other pathogens.

Internal Biosecurity (Limiting Spread Within the Herd)

• All-in, all-out (AIAO) production: In commercial settings, AIAO by room or by site dramatically reduces disease accumulation. Do not mix pigs of different ages.
• Clean and disinfect between groups: Wash all surfaces, allow to dry completely, then apply an appropriate disinfectant. Drying time is critical—most pathogens are killed by desiccation.
• Separate sick animals immediately: Have a dedicated sick pen or hospital area. Equipment used in sick pens should not be shared with healthy pens.
• Manage manure carefully: Manure is the primary vector for most enteric (gut) pathogens. Clean manure promptly, store it away from pig areas, and apply composted manure only to fields not used for pig grazing.

Biosecurity for Backyard and Small-Scale Producers

Backyard pig keepers often face unique biosecurity challenges: pigs may be close to the house, they may have visitors and children interacting with the pigs, and they may purchase animals from multiple sources at auctions or swap meets. Key recommendations:

• Never purchase pigs at auction without quarantine—auctions mix pigs from dozens of farms and are extremely high-risk disease environments
• Keep a dedicated set of boots and coveralls that stay with your pig area
• Never feed raw or inadequately cooked food scraps (prohibited in many states and a major disease risk including ASF)
• Fence to exclude wildlife, especially feral hogs
• Establish a relationship with a veterinarian before you have a crisis

Recognizing a Sick Pig: Key Warning Signs

Early detection is the most powerful tool you have in limiting disease losses. Inspect your pigs daily, and know what normal looks like so you can quickly spot abnormalities.

Normal Vital Signs in Pigs

Parameter	Normal Range
Temperature	101.5–103.5°F (38.6–39.7°C)
Heart rate	55–85 beats per minute (adults); up to 200 in piglets
Respiratory rate	15–30 breaths per minute (at rest)

Warning Signs That Require Immediate Veterinary Attention

• Temperature above 104°F or below 101°F
• Pig found in lateral recumbency (on its side), unable to rise
• Sudden unexplained death of one or more pigs
• Abortions or multiple stillbirths in the breeding herd
• Explosive diarrhea in multiple animals, especially piglets
• Open-mouth or labored breathing; blue discoloration of ears, snout, or skin
• Bloody nasal discharge or bloody diarrhea
• Suspected ASF: sudden high fever, hemorrhage, sudden death cluster
• Multiple pigs showing neurological signs (circling, paddling, head tilt)

Environmental and Management-Related Health Problems

Heat Stress

Pigs are extremely susceptible to heat stress because they cannot sweat. Their critical temperature for heat stress begins around 75–80°F (24–27°C) for growing pigs and even lower for heavy sows and boars. Heat stress reduces feed intake, growth rate, and reproductive performance, and in severe cases causes death. Signs include panting, prostration, purple discoloration of the skin, and collapse.

During hot weather: provide shade and adequate ventilation, ensure constant access to cool water (pigs drink dramatically more water when hot), use misters or drippers in pig areas, and avoid moving or working pigs during the hottest parts of the day.

Gastric Ulcers

Gastric ulceration of the pars esophagea (the non-glandular portion of the stomach near the esophagus) is extremely common in growing and finishing pigs, particularly those fed finely ground feed in commercial operations. Signs range from subclinical (only detected at slaughter) to sudden death from gastric hemorrhage. Some pigs show intermittent anorexia, pale gums from blood loss, dark tarry feces, and poor growth.

Management: coarser grinding of feed, addition of dietary fiber, reducing feed particle size below 500 microns, and minimizing stress from feed outages all help reduce gastric ulcer prevalence.

Tail Biting

Tail biting is a serious welfare and health problem in commercial pig production. It begins as exploratory behavior, quickly escalates when blood is drawn, and can result in severe wounds, spinal infections, and deaths. Risk factors include overcrowding, poor ventilation, nutritional deficiencies (especially fiber and salt), boredom, and mixing unfamiliar pigs. Environmental enrichment (straw, hanging chains, rubber toys), adequate space, and tail docking (in commercial settings) are used to reduce incidence.

Working with a Swine Veterinarian

Every pig operation—regardless of size—benefits from a relationship with a veterinarian who has swine experience. A valid Veterinarian-Client-Patient Relationship (VCPR) is required by law in the U.S. before a vet can prescribe most medications, including antibiotics. Establishing this relationship before you have a crisis allows your vet to understand your operation and respond more effectively when problems arise.

What to Expect from a Swine Vet Visit

A good swine vet will:

• Conduct a herd health visit—evaluating your housing, ventilation, records, and overall management in addition to looking at sick animals
• Recommend diagnostic testing (fecal PCR, blood serology, post-mortem examination) to identify underlying causes rather than just treating symptoms
• Work with you to develop a vaccination protocol tailored to your herd history and regional disease pressure
• Advise on biosecurity improvements
• Help you establish a written treatment protocol so employees can begin basic treatment of common conditions without waiting for the vet on every occasion

When to Call Immediately

Do not wait to call your vet when:

• Multiple pigs are dying or severely ill
• You see signs consistent with a reportable disease (ASF, classical swine fever, foot-and-mouth disease)
• A sow cannot deliver (dystocia) after active labor
• Pigs show neurological signs (meningitis, encephalitis)
• An outbreak is spreading rapidly through your barn

Record Keeping for Pig Health

Accurate records are the foundation of good pig health management. Records help you identify patterns, evaluate the success of your health program, and provide the documentation your vet needs to prescribe medications and advise on management changes.

Essential records to keep:

• Mortality records: Date, animal ID or group, age, suspected cause
• Treatment records: Date, animal ID, drug name, dose, route, withdrawal time, who administered
• Vaccination records: Date, product name and lot number, animals vaccinated, administered by
• Production records: Litter sizes, weaning weights, growth rates, feed conversion
• Diagnostic records: Lab reports, necropsy findings, culture and sensitivity results
• Purchase and movement records: Source of all incoming animals, quarantine dates

Find a Large Animal Vet Near You

Finding a veterinarian with genuine swine expertise is one of the most important investments you can make in your pig operation. Swine medicine is a specialized field, and not every large animal vet has experience with herd health management, swine reproductive programs, or complex disease investigations.

FarmVetGuide is the most comprehensive directory of large animal veterinarians in the United States, covering all 50 states and more than 2,100 counties. You can search specifically for veterinarians who work with swine, filter by services offered (mobile/farm call, emergency availability, USDA accreditation), and find contact information for practices near your farm.

Whether you raise a few backyard pigs or manage a commercial sow herd, having the right veterinarian in your corner—before a crisis hits—is the single most effective thing you can do for your animals' health.

• Find Swine Veterinarians Near You
• Find Emergency Large Animal Vets
• Find USDA Accredited Vets (required for health certificates and interstate movement)

Frequently Asked Questions About Pig Health

What are the most common diseases in backyard pigs?

The most common health problems in backyard pigs include erysipelas (diamond skin disease), respiratory infections (often caused by Mycoplasma or secondary bacteria), mange, lice, and intestinal parasites. Erysipelas is particularly important—vaccination is inexpensive and highly protective, and the disease can kill pigs rapidly. External parasites (mange and lice) are also very common in pigs acquired from multiple sources. Any new pig should be examined and treated for parasites before joining your existing animals.

How do I know if my pig has mange versus lice?

Both cause intense itching and rubbing, but the signs differ. Mange mites are microscopic—you won't see them directly, but you'll see the skin damage: red papules, crusty lesions (especially in the ear canal), and thickened, roughened skin. Lice are visible to the naked eye—look for brownish, sesame-seed sized insects at the base of hairs, particularly around the ears, neck, and flanks, along with visible nit (egg) cases attached to individual hairs. A veterinarian can confirm mange by skin scraping and microscopy. Both can be treated effectively with ivermectin or doramectin.

Can pigs give me diseases?

Yes, several pig diseases can infect humans—these are called zoonotic diseases. The most significant include: Erysipelothrix rhusiopathiae (causes skin infections called erysipeloid), Streptococcus suis (can cause severe meningitis and permanent deafness—especially important in Asia), swine influenza virus (certain strains can infect people), Salmonella (food safety concern from handling pork), and Leptospira (spread through urine, causes flu-like illness). Always wear gloves when handling sick animals, wash hands thoroughly after pig contact, and use appropriate respiratory protection when handling sick or dead pigs.

What vaccines do pigs need every year?

Core vaccines for breeding stock include: parvovirus + erysipelas + leptospira combination (given every 6 months to sows, boars, and gilts), Mycoplasma hyopneumoniae (in herds with respiratory disease), PCV2 (circovirus—given to piglets at 3–4 weeks, sow vaccination used in some programs), and swine influenza (annually). Growing pigs in commercial operations typically receive PCV2 and Mycoplasma vaccines at minimum. Your specific program should be developed with your swine veterinarian based on your herd history and regional disease risks.

What is African Swine Fever and should I be worried?

African Swine Fever (ASF) is a highly contagious, almost always fatal viral disease of pigs that is currently considered the most serious threat to global pig production. As of early 2026, ASF has not been confirmed in U.S. commercial pig herds, but it is present in some Caribbean countries and in wild boar populations in parts of Europe and Asia. There is no vaccine approved in the U.S. and no treatment. Prevention relies entirely on biosecurity: never feed raw or inadequately cooked food scraps to pigs, prevent contact between domestic pigs and feral hogs, and never bring pork products from affected countries onto your farm. If you see sudden, unexplained deaths or severe illness in multiple pigs, call your veterinarian and USDA APHIS immediately at 1-866-536-7593.

How do I prevent respiratory disease in my pigs?

Respiratory disease prevention requires a multi-pronged approach. Ventilation is critical—maintain fresh air exchange while avoiding drafts, especially at pig level. Target ammonia levels below 10 ppm. Vaccination against Mycoplasma hyopneumoniae, PRRS (if relevant to your region), and swine influenza significantly reduces respiratory disease burden. Biosecurity—especially quarantining new animals—prevents introduction of new pathogens. All-in, all-out production and thorough cleaning/disinfection between groups breaks the cycle of pathogen accumulation. Minimize stress from mixing, overcrowding, and temperature extremes. When respiratory disease does occur, prompt diagnosis (including pathogen identification) allows targeted treatment rather than broad-spectrum antibiotic guesswork.

When do I need a health certificate to move pigs?

Interstate movement of pigs in the U.S. generally requires a Certificate of Veterinary Inspection (CVI, also called a health certificate), issued by a federally accredited veterinarian (USDA APHIS accredited). Requirements vary by state of destination—some states require additional testing (for brucellosis, pseudorabies, or other diseases) or official identification tags. You should contact the state veterinarian's office in your destination state before moving animals, and allow enough time to schedule a vet examination and obtain required test results. Intrastate movement requirements vary by state as well. Your veterinarian or local USDA APHIS Veterinary Services office can provide current requirements for your specific movement.

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