Risk factors related to Toxoplasma gondii seroprevalence in indoor-housed Dutch dairy goats

Prev Vet Med. 2016 Feb 1:124:45-51. doi: 10.1016/j.prevetmed.2015.12.014.

Abstract

Toxoplasma gondii can cause disease in goats, but also has impact on human health through food-borne transmission. Our aims were to determine the seroprevalence of T. gondii infection in indoor-housed Dutch dairy goats and to identify the risk factors related to T. gondii seroprevalence. Fifty-two out of ninety approached farmers with indoor-kept goats (58%) participated by answering a standardized questionnaire and contributing 32 goat blood samples each. Serum samples were tested for T. gondii SAG1 antibodies by ELISA and results showed that the frequency distribution of the log10-transformed OD-values fitted well with a binary mixture of a shifted gamma and a shifted reflected gamma distribution. The overall animal seroprevalence was 13.3% (95% CI: 11.7–14.9%), and at least one seropositive animal was found on 61.5% (95% CI: 48.3–74.7%) of the farms. To evaluate potential risk factors on herd level, three modeling strategies (Poisson, negative binomial and zero-inflated) were compared. The negative binomial model fitted the data best with the number of cats (1–4 cats: IR: 2.6, 95% CI: 1.1–6.5; > = 5 cats:IR: 14.2, 95% CI: 3.9–51.1) and mean animal age (IR: 1.5, 95% CI: 1.1–2.1) related to herd positivity. In conclusion, the ELISA test was 100% sensitive and specific based on binary mixture analysis. T. gondii infection is prevalent in indoor housed Dutch dairy goats but at a lower overall animal level seroprevalence than outdoor farmed goats in other European countries, and cat exposure is an important risk factor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Protozoan / blood
  • Binomial Distribution
  • Dairying
  • Enzyme-Linked Immunosorbent Assay / veterinary
  • Goat Diseases / blood
  • Goat Diseases / epidemiology*
  • Goat Diseases / parasitology
  • Goats
  • Housing, Animal
  • Netherlands / epidemiology
  • Poisson Distribution
  • Prevalence
  • Regression Analysis
  • Risk Factors
  • Seroepidemiologic Studies
  • Toxoplasma / isolation & purification*
  • Toxoplasmosis, Animal / blood
  • Toxoplasmosis, Animal / epidemiology*
  • Toxoplasmosis, Animal / parasitology

Substances

  • Antibodies, Protozoan