title: A new single-dose bivalent vaccine of porcine circovirus type 2 and Mycoplasma hyopneumoniae elicits protective immunity and improves growth performance under field conditions.
abstract: The efficacy of the new single-dose bivalent vaccine of porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae was evaluated under field conditions for registration as recommended by the Republic of Korea's Animal, Plant & Fisheries Quarantine & Inspection Agency. Three farms were selected based on their history of co-infection with PCV2 and M. hyopneumoniae. On each farm, a total of 80 3-week-old pigs were randomly allocated to one of two treatment groups: (i) vaccinated (n=40) and (ii) unvaccinated (n=40) animals at 3 weeks of age. Protection by the bivalent vaccine helped increase the market weight by 6.2 kg/pig (106.2 kg in vaccinated group vs. 100 kg in unvaccinated group; P<0.05) and decreased mortality rate by 13.4% (0.8% in unvaccinated group vs. 14.2% in unvaccinated group; P<0.05). Vaccinated animals induced PCV2-specific neutralizing antibodies (NA) and interferon-γ secreting cells (IFN-γ-SC), and M. hyopneumoniae-specific IFN-γ-SC. Vaccinated animals displayed a reduced PCV2 load in the blood and M. hyopneumoniae load in nasal swabs compared to unvaccinated animals. Vaccination of pigs against PCV2 and M. hyopneumoniae effectively reduced the lung and lymphoid lesion scores compared to unvaccinated animals in all 3 farms. The new bivalent vaccine is very efficacious in controlling PCV2 and M. hyopneumoniae infection based on clinical, immunological, virological, and pathological evaluations under field conditions.
authors.affiliation: Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea.
authors.forename: Jiwoon
authors.initials: J
authors.lastname: Jeong
authors.affiliation: Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea.
authors.forename: Changhoon
authors.initials: C
authors.lastname: Park
authors.affiliation: Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea.
authors.forename: Kyuhyung
authors.initials: K
authors.lastname: Choi
authors.affiliation: Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea. Electronic address: swine@snu.ac.kr.
authors.forename: Chanhee
authors.initials: C
authors.lastname: Chae
mesh_terms: D000818:Animals; D001428:Bacterial Vaccines / Q000276:immunology / Q000627:therapeutic use; D018173:Circoviridae Infections / Q000276:immunology / Q000662:veterinary*; D017925:Circovirus / Q000145:classification / Q000276:immunology*; D060085:Coinfection / Q000276:immunology / Q000517:prevention & control; D005260:Female; D045705:Mycoplasma hyopneumoniae / Q000276:immunology*; D045729:Pneumonia of Swine, Mycoplasmal / Q000276:immunology* / Q000517:prevention & control; D034421:Sus scrofa / Q000254:growth & development / Q000276:immunology; D013552:Swine; D013553:Swine Diseases / Q000276:immunology / Q000382:microbiology / Q000821:virology; D014611:Vaccination / Q000662:veterinary; D017778:Vaccines, Combined / Q000276:immunology / Q000627:therapeutic use*; D014765:Viral Vaccines / Q000276:immunology / Q000627:therapeutic use
chemical_list: D001428:Bacterial Vaccines; D017778:Vaccines, Combined; D014765:Viral Vaccines
keywords: Bivalent vaccine; Mycoplasma hyopneumoniae; Porcine circovirus type 2; Porcine respiratory disease complex