Pig Diseases in the USA

1. Pig Diseases in the USA John J. McGlone, Ph.D. Pork Industry Institute Texas Tech University

2. Pig Disease Categories Diseases we do not want to get (that we know about) Diseases that are regulated by the US government with an eye towards eradication Other diseases to manage

3. Pig diseases we do not want Hog Cholera Hoof and Mouth  African Swine Fever

4. Hog Cholera Classic Swine Fever Viral; single stand of RNA Family: Togaviridae, Genus: Pestivirus Same family as BVD USA eradication was from 1962-1976 Has not been eradicated from Europe (note The Netherlands).

5. Hog Cholera Infected pigs shed virus for 10-20 days Can be transmitted in utero Feeding garbage exacerbates the spread; leading to the outlaw of this practice in many states. 6-day incubation period; Respiratory; enteric; anorexia; hunched; ataxia; leukopenia

6. Foot (Hoof) and Mouth A picornavirus Family: Picornaviridae; Genus: Apthovirus(Aptha, in Greek means vessicles in the mouth) RNA virus; 7 serotypes Can infect pigs, cattle, sheep & goats Aerosol is highly contagious

7. Foot and Mouth Can be transmitted in semen; not the fetus North and Central America is free; South America, Africa & Asia are infected 3-5 day incubation period Vessicles in mouth and between toes; Sharp fever, abortion; skin lesions leading to sluffing of tissue

8. African Swine Fever DNA-containing virus; Family: Iridovirdae Only pigs (including wart hogs and the like) are susceptible; ticks may be carriers High fever & mortality; respiratory distress;Hemorragic disease May resemble Hog Cholera Little antibody formation -- no vaccine

9. Vaccines? Foot and Mouth -- yes Hog Cholera -- yes African Swine Fever -- no What else is out there???

10. Diseases that are regulated by the US government Pseudorabies Brucellosis You can be validated as free from these by state agencies Feral pigs are major carriers of these and other diseases

11. PseudorabiesAujeszky�s Disease Viral; Herpesviridae of the subfamily alphavuirus; DNA While pigs are the only �natural� host, it infects all farm animals and vermin All pigs can be infected; suckling pigs are least affected Transmitted by aerosol, fluids, incl. semen

12. PRV 2-4 day incubation period Nervous symptoms among younger pigs (ataxia) and respiratory and reproductive symptoms among older pigs (G-F & sows) Mortality can be 100% among piglets Farrowing rate is reduced due to abortions and many stillbirths are observed

13. PRV Few gross lesions; respiratory & GI tracts are affected Genetically-engineered vaccine allows vaccination titers to be distinguished from natural infections States & USA quarantine the herd as a part of the eradication program

14. Brucellosis Bacteria -- Brucella suis Infects pigs and humans (a different organism infects cattle -- Brucella abortus -- with only a little cross over) Nearly eradicated in the USA (TX still infected) Venereal disease of swine; Reproductive failures, especially abortions

15. Major Classes of Production Diseases (ones some chose to live with) Respiratory Enteric Reproductive Parasitic Metabolic

16. Respiratory PRRS Atrophic Rhinitis Mycoplasmal pneumonia Swine influenza Actinobacillus pleuropneumoniae

17. PRRS Lelystad virus In 1997, 68.5% of USA farms were seropositive Farrowing rate declines by 50% Stillbirths & preweaning mortality & growing pig mortality increases by 300%(1-3 pigs/litter born dead; 2 to 6 % mortality in each of nursery & G-F)

18. PRRS Modified live vaccine offers poor protection No effective treatment Widespread problem; not solved by SEW or any measure other than �all-in-all-out and wait� or depopulate

19. Atrophic Rhinitis Caused by 2 organisms: Bordetella bronchiseptica causes a non-progressive form of AR Progressive (severe) AR is caused by toxigenic Pasteurella Multocida When both organisms are present, the AR is especially symptomatic

20. Atrophic Rhinitis Severe turbinate atrophy, bloody & crooked noses, followed by increased incidence of respiratory tract lesions and infections Genetic predisposition is possible Caustic air environments exacerbate the symptoms SEW may help eliminate the bugs

21. Atrophic Rhinitis Production set-backs are the most costly Vaccines are available for BB & PM Sulfamethazine is effective, but banned in some countries; a host of partially effective antibiotics are available Suggest: Depopulation

22. Mycoplasmal pneumonia Also called enzootic pneumonia Bacteria: Mycoplasma hyopneumoniae Nose-to-nose contact spreads the organism Highly prevalent in the the USA, Europe, Australia and most modern pig countries Lungs have lesions; secondary infections; performance set-backs

23. Mycoplasmal pneumonia Several antibiotics are available; all are only partially effective SEW may help prevent its spread Suggest: Depopulate

24. Actinobacillus pleuropneumoniae Also called Haemophilus pleuropneumoniae Bacteria of the name: Actinobacillus pleuropneumoniae Widespread distribution Economic cost is associated with rapid, high mortality, rather than only production set-backs

25. Actinobacillus pleuropneumoniae Brought on by stress; can be acute or chronic Rapid fever, foamy, bloody respiratory tract discharge; death within 36 hours; tract is inflamed and bloody; Rapid, high levels of certain antibiotics can be effective Suggest: Clean up or depopulate

26. Swine influenza Also called swine flu, caused by a virus; Influenza A virus (Orthomyxoviridae family); Different serotypes; Birds and other mammals may carry or become infected by the virus -- including humans Mild stress brings out symptoms

27. Swine influenza Significant respiratory symptoms, including dog-barking type of coughing Fever is mild; 1-3 day incubation period No specific treatment is available; make sure water is available

28. Pneumonic Pasteurellosis From Pasteurella multocida (gram negative coccobacillus) See Atrophic Rhinitis for more details Often isolated and labeled the cause of death following acute respiratory distress Many antibiotics are available

29. Enteric Diseases TGE E. coli Swine dysentery Ileitis (proliferative enteropathies) Clostridium Coccidia Rotavirus

30. TGE Transmissible Gastro Enteritis Viral: Coronavirus; RNA Severe enteric symptoms; there is a Porcine Respiratory Coronavirus (PRCV) that cross reacts with TGE

31. TGE 18 h to 3 day incubation period; then severe scours; 50-100% of piglets will die; fewer older pigs; sows vomit; watery to yellow scours with a foul odor Destruction of intestinal epithelium; pigs unthrifty for life Feed-back of dead pigs is best Strikes more in winter

32. Eschericha coli E. coli is a common intestinal bacteria; pathogenic E. coli is the enteric organism; Enteric Colibacillosis; many serotypes Gram negative, flagellated rods; bacteria produces endotoxin Symptoms like TGE; lower death loss and it should respond to antibiotics if treated early

33. Swine dysentery Bloody scours; mucohemorrhagic diarrhea Bacteria: Treponema hyodysenteriae; 7 serotypes known Bloody scours, especially in G-F pigs Fever; deaths if untreated Several antibiotics are available Suggest: depopulation

34. Ileitis (proliferative enteropathies) Several diseases in this category; some bacterial, others of unknown cause Campylobacter genus is involved Sudden deaths; some times bloody scours; slow growth Some antibiotics are somewhat effective

35. Clostridium Fatal necrotic enteritis Several bacteria, especially Clostridium perfringens type C (also tetanus & botulism) Young piglets will die within 36 hours; in the chronic form they may live 1 week Dehydration; red feces Antibiotics can be effective

36. Coccidia Obligatory intracellular protozoan parasite Isospora suis Symptoms start 7-14 days of age; yellow to grayish diarrhea; rancid odor Several anticoccidials to piglets (giving to sows not effective) Suggest: stringent sanitation; all-in-all-out

37. Rotavirus Virus of the Reoviridae family of the genus Rotavirus Very common in nature; many serotypes 12-24 h incubation period; nursing pigs most affected; can be high mortality or a mild scours; weanlings may show signs Expose sows to give piglets immunity

38. Others Reproductive Parasites PSS/PSE Prolapse, Ulcer & Hernia Mycotoxins Skin/joint problems, esp. Erysipelas MMA Behavioral problems

39. Reproductive Brucellosis (see above) Leptospirosis Parvo Virus PRRS (see above)

40. Leptospirosis Bacteria of the Leptospira; gram negative rods; 7 serotypes (or more) Infection of mucous membranes Mild symptoms of anorexia, listlessness Major reproductive problems: abortions, lower farrowing rates Vaccines are available

41. Parvo Virus Virus of family Parvoviridae; DNA Embryonic and fetal deaths Main symptom is stillborn pigs or lower numbers born alive Vaccines are available

42. Parasites No excuse to have them Trichinosis Ascarid Kidney Mange Lice

43. PSS/PSE Genetic condition caused by a mutation of a gene Malignant hyperthermia Halothane gene Hal 1873; genetic test Single gene: carrier, mono-mutants Two genes; di-mutant Test and eliminate

44. Prolapse, Ulcer & Hernia Genetic predisposition to each Prolapses can be rectal or vaginal Hernias can be inguinal or scrotal Multi-factorial causes Diet contributes to all, but not the main cause

45. Mycotoxins Metabolites of mold/fungal growth from the genus Fusarium Aflotoxins, Ochratoxin and citrinin, Trichothecenes, Zeralenone, Ergot and Fumonisins Reduce feed intake and several cause reproductive problems due to steroid activity

46. MMA Mastitis, Metritis, Agalagtia (usually hypogalactia) Multi-factorial cause; genetic predisposition; bacterial infections; constipation; lack of exercise Piglets waste away and die due to malnutrition

47. Skin/joint problems, esp. Erysipelas Erysipelas, diamond skin disease, caused by a bacteria Erysipelothrix rhusiopathiae; fever, followed by skin lesions, and then joint inflammation Vaccines available for Erysipelas Other bacteria can cause skin and/or joint inflammation: Streptococci, Staphlococci

48. Behavioral Problems Tail biting & ear chewing Savaging piglets Naval/Urine sucking Not a problem:-- bar biting-- phantom nest building-- aggression in pigs less than 100 lb