title: Oxidative stress in dairy cows naturally infected with the lungworm Dictyocaulus viviparus (Nematoda: Trichostrongyloidea).
abstract: The aim of this study was to analyse the oxidative and anti-oxidant status in serum samples from dairy cows naturally infected by Dictyocaulus viviparus and its relation with pathological analyses. The diagnosis of the disease was confirmed by necropsy of one dairy cow with heavy infection by the parasite in the lungs and bronchi. Later, blood and faeces were collected from another 22 cows from the same farm to measure reactive oxygen species (ROS) levels, thiobarbituric acid-reactive substances (TBARS), catalase (CAT) and superoxide dismutase (SOD) activities on day 0 (pre-treatment) and day 10 (post-treatment with eprinomectin). Faecal examination confirmed the infection in all lactating cows. However, the number of D. viviparus larvae per gram of faeces varied between animals. Cows showed different degrees of severity according to respiratory clinical signs of the disease (cough and nasal secretion). Further, they were classified and divided into two groups: those with mild (n = 10) and severe disease (n = 12). Increased levels of TBARS (P < 0.001), ROS (P = 0.002) and SOD activity (P < 0.001), as well as reduced CAT activity (P < 0.001) were observed in cows with severe clinical signs of the disease compared to those with mild clinical signs. Eprinomectin treatment (day 10) caused a reduction of ROS levels (P = 0.006) and SOD activity (P < 0.001), and an increase of CAT activity (P = 0.05) compared to day 0 (pre-treatment). TBARS levels did not differ with treatment (P = 0.11). In summary, increased ROS production and lipid peroxidation altered CAT and SOD activities, as an adaptive response against D. viviparus infection, contributing to the occurrence of oxidative stress and severity of the disease. Treatment with eprinomectin eliminated the infection, and thus minimized oxidative stress in dairy cows.
authors.affiliation: Graduate Program in Toxicological Biochemistry,Department of Biochemistry and Molecular Biology,Universidade Federal de Santa Maria (UFSM),Santa Maria,RS,Brazil.
authors.forename: A D
authors.initials: AD
authors.lastname: da Silva
authors.affiliation: Graduate Program in Toxicological Biochemistry,Department of Biochemistry and Molecular Biology,Universidade Federal de Santa Maria (UFSM),Santa Maria,RS,Brazil.
authors.forename: A S
authors.initials: AS
authors.lastname: da Silva
authors.affiliation: Department of Microbiology and Parasitology,Universidade Federal de Santa Maria (UFSM),Santa Maria,RS,Brazil.
authors.forename: M D
authors.initials: MD
authors.lastname: Baldissera
authors.affiliation: Laboratory of Veterinary Pathology,Instituto Federal Catarinense (IFC),Concórdia,SC,Brazil.
authors.forename: C I
authors.initials: CI
authors.lastname: Schwertz
authors.affiliation: Graduate Program in Toxicological Biochemistry,Department of Biochemistry and Molecular Biology,Universidade Federal de Santa Maria (UFSM),Santa Maria,RS,Brazil.
authors.forename: N B
authors.initials: NB
authors.lastname: Bottari
authors.affiliation: Graduate Program in Toxicological Biochemistry,Department of Biochemistry and Molecular Biology,Universidade Federal de Santa Maria (UFSM),Santa Maria,RS,Brazil.
authors.forename: G M
authors.initials: GM
authors.lastname: Carmo
authors.affiliation: Department of Veterinary Population Medicine,College of Veterinary Medicine,University of Minnesota,USA.
authors.forename: G
authors.initials: G
authors.lastname: Machado
authors.affiliation: Laboratory of Veterinary Pathology,Instituto Federal Catarinense (IFC),Concórdia,SC,Brazil.
authors.forename: N J
authors.initials: NJ
authors.lastname: Lucca
authors.affiliation: Laboratory of Veterinary Pathology,Instituto Federal Catarinense (IFC),Concórdia,SC,Brazil.
authors.forename: L C
authors.initials: LC
authors.lastname: Henker
authors.affiliation: Laboratory of Veterinary Pathology,Instituto Federal Catarinense (IFC),Concórdia,SC,Brazil.
authors.forename: M M
authors.initials: MM
authors.lastname: Piva
authors.affiliation: Laboratory of Veterinary Pathology,Instituto Federal Catarinense (IFC),Concórdia,SC,Brazil.
authors.forename: P
authors.initials: P
authors.lastname: Giacomin
authors.affiliation: Graduate Program in Toxicological Biochemistry,Department of Biochemistry and Molecular Biology,Universidade Federal de Santa Maria (UFSM),Santa Maria,RS,Brazil.
authors.forename: V M
authors.initials: VM
authors.lastname: Morsch
authors.affiliation: Graduate Program in Toxicological Biochemistry,Department of Biochemistry and Molecular Biology,Universidade Federal de Santa Maria (UFSM),Santa Maria,RS,Brazil.
authors.forename: M R C
authors.initials: MRC
authors.lastname: Schetinger
authors.affiliation: Cooperativa de Produção e Consumo Concórdia (COPÉRDIA),Concórdia,SC,Brazil.
authors.forename: R A
authors.initials: RA
authors.lastname: da Rosa
authors.affiliation: Laboratory of Veterinary Pathology,Instituto Federal Catarinense (IFC),Concórdia,SC,Brazil.
authors.forename: R E
authors.initials: RE
authors.lastname: Mendes
mesh_terms: D000818:Animals; D001980:Bronchi / Q000469:parasitology; D002374:Catalase / Q000097:blood; D002417:Cattle; D002418:Cattle Diseases / Q000469:parasitology / Q000473:pathology*; D004021:Dictyocaulus / Q000302:isolation & purification*; D004022:Dictyocaulus Infections / Q000473:pathology*; D005243:Feces / Q000469:parasitology; D008168:Lung / Q000469:parasitology; D018384:Oxidative Stress; D010270:Parasite Egg Count; D017382:Reactive Oxygen Species / Q000097:blood; D013482:Superoxide Dismutase / Q000097:blood; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis
chemical_list: D017382:Reactive Oxygen Species; D017392:Thiobarbituric Acid Reactive Substances; D002374:Catalase; D013482:Superoxide Dismutase