title: Effect of exposure to Neospora caninum, Salmonella, and Leptospira interrogans serovar Hardjo on the economic performance of Irish dairy herds.
abstract: The objective of the current study was to quantify the effects of exposure to Salmonella, Neospora caninum, and Leptospira interrogans serovar Hardjo (L. hardjo) on dairy farm profitability and to simulate the effect of vaccination for Salmonella and L. hardjo on dairy farm profitability. The production effects associated with exposure to each of these pathogens in study herds were defined under 3 categories: (1) milk production effects, (2) reproduction effects (including culling), and (3) mortality effects. The production effects associated with exposure to Salmonella, N. caninum, and L. hardjo were incorporated into the Moorepark Dairy Systems Model. In the analysis, herds negative for exposure to Salmonella, N. caninum, and L. hardjo were assumed baseline herds, with all results presented relative to this base. In simulations examining the effect of vaccination for Salmonella and L. hardjo on farm profitability, vaccinated herds (vaccination costs included) were considered as baseline herds and results were presented relative to this base. Total annual profits in unvaccinated herds were reduced by €77.31, €94.71, and €112.11 per cow at milk prices of €0.24, €0.29, and €0.34/L, respectively, as a result of exposure to Salmonella. In the current study, herds positive for exposure to Salmonella recorded a 316-kg reduction in milk yield, whereas no association was detected between exposure to N. caninum or L. hardjo and milk production. Exposure to both N. caninum and L. hardjo was associated with compromised reproductive performance. Herds positive for exposure to N. caninum and Salmonella had greater rates of adult cow mortality and calf mortality, respectively. Vaccination for both Salmonella and L. hardjo was associated with improved performance in study herds. Exposure to N. caninum resulted in a reduction in annual farm profits of €11.55, €12, and €12.44 per cow at each milk price, whereas exposure to L. hardjo resulted in a reduction in annual farm profits of €13.83, €13.78, and €13.72 per cow at each milk price. Herds that tested positive for exposure to Salmonella and L. hardjo were compared with herds vaccinated for the respective pathogens. Herds vaccinated for Salmonella generated €67.09, €84.48, and €101.89 per cow more profit at each milk price compared with herds positive for exposure. Similarly, herds vaccinated for L. hardjo generated €9.74, €9.69, and €9.63 per cow more profit compared with unvaccinated exposed herds. However, herds that tested negative for exposure to Salmonella and L. hardjo generated additional profits of €10.22 and €4.09 per cow, respectively, compared with vaccinated baseline herds.
authors.affiliation: Teagasc, Animal and Grassland, Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland; School of Veterinary Medicine, UCD Veterinary Sciences Centre, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: E
authors.initials: E
authors.lastname: O' Doherty
authors.affiliation: Teagasc, Animal and Grassland, Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland.
authors.forename: R
authors.initials: R
authors.lastname: Sayers
authors.affiliation: School of Veterinary Medicine, UCD Veterinary Sciences Centre, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: L
authors.initials: L
authors.lastname: O' Grady
authors.affiliation: Teagasc, Animal and Grassland, Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland. Electronic address: Laurence.Shalloo@Teagasc.ie.
authors.forename: L
authors.initials: L
authors.lastname: Shalloo
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial; D002417:Cattle; D002418:Cattle Diseases / Q000191:economics / Q000453:epidemiology / Q000382:microbiology*; D003048:Coccidiosis / Q000453:epidemiology / Q000662:veterinary*; D005260:Female; D007494:Ireland / Q000453:epidemiology; D007921:Leptospira interrogans / Q000145:classification; D007922:Leptospirosis / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D008892:Milk / Q000191:economics; D018688:Neospora; D012098:Reproduction; D012475:Salmonella; D012481:Salmonella Infections, Animal / Q000453:epidemiology / Q000382:microbiology*
chemical_list: D000907:Antibodies, Bacterial
keywords: Leptospira interrogans serovar Hardjo (L. hardjo); Neospora caninum; Salmonella; dairy farm profitability