Swine Diseases and Atrophic Rhinitis

Swine Systems

• Gilts undergo pregnancy
• Farrowing occurs in the farrow barn, from birth to weaning.
• Weaning happens at around 21 days, then pigs move to a nursery
• Pigs that weigh between 50-60 pounds are transferred to a finish barn.
• Pigs are sent to market when they are approximately 5-6 months old and weigh 280 pounds

Swine Diseases

• Swine can be hosts to viral and bacterial diseases

Swine Bacterial Diseases

• Atrophic Rhinitis
• E. Coli
• Swine Dysentery
• Clostridial Disease
• Exudative Dermatitis
• Leptospirosis
• Erysipelas
• Mycoplasma
• APP
• Glasser's Disease

Swine Viral Diseases

• TGEV
• PPV
• PRRS
• ASF
• PED

Atrophic Rhinitis (AR)

• AR is caused by Bordetella bronchiseptica, Pasteurella multocida
• Signs include snuffling, sneezing, snorting, and serous or mucopurulent nasal discharge
• The disease destroys the nasal turbinates
• Mortality is low
• Growth rate and feed efficiency are significantly affected

Early Signs of AR

• Lateral or dorsal deviation of the snout and a dorsal deviation often results in shortening or wrinkling of the skin over the snout

Control of AR

• Improve husbandry, management, and housing through ventilation
• Vaccinate the breeding stock, pigs or both.
• Administer antibiotic therapy, though this is questionable

Escherichia Coli

• The illness is also known as baby pig scours, white scours, or bacterial enteritis
• Diarrhea present is hypersecretory in nature, varying in color
• Clear and watery in neonates, potentially white or yellow
• Progress leads to dehydration, shivering, hypothermia, and a roughened coat
• Can be followed by death

Control of E. Coli

• Enforce proper sanitation
• Practice proper sow nutrition and vaccination
• Establish the origin of breeding stock
• Vaccinate gestating sows
• Administer antibiotics
• Practice "All in All" out method during farrowing
• Clear fecal slurries

Colibacillosis - ED

• This is a specific type of E. Coli
• ED is an acute, often-fatal enterotoxemia of recently weaned piglets
• It is caused by a few serotypes of Escherichia coli
• It is characterized by edema at certain sites
• Signs include sudden death, neurologic signs and swollen eyelids because of edema
• Diarrhea is usually not a sign

Control of ED

• Management and nutritional considerations
• Use antimicrobials and Immunoprophylaxis
• Competitive exclusion and negative herds can help, as well as controlling entry
• Natural resistance via genetically resistant pigs

Swine Dysentery

• It is caused by Brachyspira hyodysenteriae + Brachyspira pilosicoli (spirochete)
• Also known as bloody scours, black scours or vibrionic dysentery, severe and infectious
• Any age group of pigs can be affected, but it is most common between 8-16 weeks
• Signs include diarrhea initially mucoid grey to yellow that quickly becomes mucohemorrhagic
• Fresh red blood may be present in the mucus of the diarrhea and dehydration quickly follows

Swine Dysentery Treatment

• Method 1: All piglets less than 3 weeks are taken to a clean site and rasied there
• Method 2: Medicate to reduce herd down to manageable numbers, and give carbadox, lincomycin or tiamulin
• Method 3: Complete depopulation if its become endemic
• Complete depopulation typically occurs when biosecurity is difficult to manage and sanitation is difficult

Clostridial Diarrhea

• C. perfringens type C: causes variable morbidity & high mortality in neonates or suckling pigs
• C. perfringens type A: moderate morbidity & lower mortality
• C. difficile: this has variable morbidity and mortality
• Type C is most prevalent, mainly affecting piglets less than 1 week old between 1-3 day
• This leads to Necrohemorrhagic enteritis in the intestine, which means hemorrhagic diarrhea and collapse followed by death

Control of Clostridial Diarrhea

• Administer immune antiserum within 2 hours of birth
• Piglets can be protected if dams are injected with bacterin-toxoid 5-6 weeks prior to farrowing or 2-3 weeks before
• Some benefit can result by feeding antibiotics with anticlostridial activity to sows before farrowing and during lactation

Exudative Dermatitis

• This is caused by Staphylococcus hyicus
• Aka 'greasy pig' disease
• Usually seen in pigs less than 8 weeks, but can occur in older pigs, but seldom in adult pigs
• Main source of infection is from the sow to the piglet during nursing
• The bacteria are unable to penetrate intact skin, so infection is passed through lacerations on legs & feet
• Signs are the reddening of the skin with erosions at the coronary band, depression, anorexia and red areas of skin that turn into brown spots and increased production of serum exudates that cover the entire pig
• Control: Administer high dose antibiotics for 7 – 10 days

Leptospirosis

• This is caused by Leptospira spp.
• Bacteria are transferred from exposure to infected urine of wildlife or other pigs
• Leptospira penetrates mucous membranes, wounds/abrasions
• Signs are abortion 2 – 4 weeks before term and SMEDI (stillbirth, mummification, embryonic death, infertility)
• Vaccination, antibiotics and vector control are available, as well as treated water

Erysipelas

• Is caused by Erysipelothris rhusiopathiae
• This is an infectious disease of growing or adult pigs
• Has three forms:
• Acute
• Mild
• Chronic
• There are at least 26 serotypes of Erysipelothrix spp., but pigs are only susceptible to at least 15
• Healthy pigs can be carriers

Clinical Signs of Erysipelas

• Acute Signs include sudden death and the host being pyrexic
• Reddened or cyanotic skin can be found around ears, snout and jowls, throat and ventral abdomen
• Red to purple raised areas, often referred to as diamond
• Chronic signs follow an acute outbreak and include the Enlargement of joint

Control of Erysipelas

• Outbreaks may be managed by administering penicillin, potentially added to drinking water
• Erysipelas antiserum is effective here
• Vaccination is an option in the face of an outbreak, such as when the pig is less than 6 months old
• Vaccinate again at 6.5 months and booster 1 month later
• Vaccinate sows and pigs before breeding

Glasser's Disease

• Is caused by Haemophilus parasuis
• Aka porcine polyserositis or infectious polyarthritis
• Stress plays a critical role in predisposition to the process to disease
• Most often seen between 3 weeks to 4 months of age, following a stressor
• Signs include fever, depression, breathing difficulties and anorexia, as well as CNS disturbance (tremors, incoordination, posterior paresis, lateral recumbency)
• Vaccinate weanlings

Mycoplasma

• Is caused by Mycoplasma hyopneumoniae
• Aka EP = enzootic pneumonia and sometimes called SEP
• This is a chronic respiratory disease of all ages of pigs
• Interacts & contributes to other respiratory diseases, especially porcine respiratory disease complex
• Signs include a persistent dry cough, decreased growth rates and sporadic dyspnea

Contagious Pleuropneumonia

• It is caused by Actinobacillus pleuropneumoniae (APP)
• It is a severe and contagious respiratory disease
• Affects growing swine up to ~ 6 months
• Has acute and chronic forms
• Signs include prostration, stiffness, fever, apathy, anorexia, and potentially vomiting and diarrhea
• Treatment involves vaccination, medication and improved husbandry

Transmissible Gastroenteritis - TGE

• It is caused by an enteric coronavirus
• It affects pigs of all ages
• The virus destroys the epithelial cells of the jejunum and ileum
• The incubation period is only 18 hours, but outbreaks more often occur in colder months
• Signs are age dependent
• Symptoms in nursing piglets are diarrhea and dehydration (often see undigested milk curds)
• Gestating sows experience abortion and the diarrhea

Porcine Parvovirus - PPV

• It is caused by a parvovirus
• It is is most often asymptomatic in the herd
• If symptomatic, it causes mummification of fetuses if sow infected in the first 70 days of gestation
• Abortions are rare and still births increased here
• Control measures are to vaccinate breeding stock, 2 shots, 2 weeks apart before breeding

Porcine Reproductive & Respiratory Syndrome

• PRRS virus is an enveloped RNA virus in genus Arterivirus, family Arteriviridae
• It is characterized by two overlapping clinical presentations (Reproductive and respiratory)
• This leads to Reproductive impairment or failure in breeding animals and Respiratory disease in pigs of any age
• The virus replicates in macrophages

Effects of PRRS

• Can affect all age groups, more often observed in young pigs
• An affected herd can occur when there is acute or endemic disease
• Clinical signs are highly dependent on the existing herd health status - in a healthy herd there may be no signs
• Pig’s immune system is compromised here leading to secondary infections

Respiratory PRRS

• Acute in a healthy herd with mild symptoms
• Established disease causes the biggest problems
• Signs are a inappetance, signs of pneumonia (coughing), and malabsorption & wasting

Reproductive PRRS

• Dry sows = inappetance, late term abortions, and prolonged anoestrus
• Farrowing sows = Agalactia and Mastitis, plus Stillbirths & mummified fetuses

Control of PRRS

• Vaccination to control signs and reduce shedding
• Treat secondary respiratory and enteric infections with antibiotics for 3-4 wks in sows and boars when either is suspected of having contracted a virus
• A professional can also use water-soluble antibiotics and medication in feed
• Treats early or with interventions which will reduce abortions, miscarriages, stillbirths, or mummification

Typical Swine Vaccination Schedule

• See Table Below
• Atrophic rhinitis = piglets need 7-10 days shots and Replacements (Gilts & boars), and Sows need shots
• Mycoplasma = piglets need 7-10 days shots, and Sows need shots
• Erysipelas = piglets Before/ after weaning get shots, and Replacements (Gilts & boars), and Sows need shots
• Contagious pleuropneumonia = Weaglings need shots
• Leptospirosis = Repalcement (Gilts & boars), & Sows & boars need shots
• Parvovirus = only reaplacement Gilts need shots
• Transmissible gastroenteritis = only reaplacement Gilts, and Sows need shots
• Escherichia coli = Only Weaglings and Sows need shots
• Glasser’s = Only Weaglings need shots

Preventative Measures

• It is much easier to use good management practices to prevent swine diseases
• Fresh water is very critical for pigs, beyond dehydration
• It is best practice for movement of pigs from one unit to another
• The industry is highly regulated