Inferring phenotypic causal networks for tick infestation, Babesia bovis infection, and weight gain in Hereford and Braford cattle using structural equation models

Author(s):Show less -

Cavani, Ligia ^{[1, 2]} ; Lopes, Fernando Brito ^{[2, 3]} ; Giglioti, Rodrigo ^[4] ; Bresolin, Tiago ^[1] ; Campos, Gabriel Soares ^[5] ; Okino, Cintia Hiromi ^[4] ; Gulias-Gomes, Claudia Cristina ^[6] ; Caetano, Alexandre Rodrigues ^[7] ; Oliveira, Marcia Cristina de Sena ^[4] ; Cardoso, Fernando Flores ^[6] ; Rosa, Guilherme Jordao de Magalhaes ^[2] ; de Oliveira, Henrique Nunes ^[1]

Affiliation

^[1] Sao Paulo State Univ UNESP, Sch Agr & Veterinarian Sci, Via Acesso Prof Paulo Donato Castellane S-N, BR-14884900 Jaboticabal, SP - Brazil

^[2] Univ Wisconsin, Dept Anim Sci, 436 Anim Sci Bldg, 1675 Observ Dr, Madison, WI 53706 - USA

^[3] Embrapa Cerrado, Empresa Brasileira Pesquisa Agr, BR-020, Km 18 S-N, BR-73310970 Brasilia, DF - Brazil

^[4] Embrapa Pecuaria Sudeste, Empresa Brasileira Pesquisa Agr, Rodovia Washington Luiz, Km 234 S-N, BR-13560970 Sao Carlos, SP - Brazil

^[5] Fed Univ Rio Grande Sul UFRGS, Av Paulo Gama 110, BR-90040060 Porto Alegre, RS - Brazil

^[6] Embrapa Pecuaria Sul, Empresa Brasileira Pesquisa Agr, Rodovia BR-153, Km 632, 9, BR-96401970 Bage, RS - Brazil

^[7] Embrapa Recursos Genet & Biotecnol, Empresa Brasileira Pesquisa Agr, Parque Estacao Biol, PqEB, Av W5 Norte Final, BR-70770917 Brasilia, DF - Brazil

• Document type: Journal article
• Source: LIVESTOCK SCIENCE; v. 238, AUG 1 2020.
• Web of Science Citations: 0

Abstract

Tick infestation and associated diseases (i.e., babesiosis) constitute major drawbacks for improvement of beef cattle productivity in the tropics, mainly when purebred and crossbred taurine animals are used. Host-parasite-pathogen interactions form complex biological systems that are poorly understood and which significantly affect production and quality traits in ways yet to be dissected and described. This research was carried out to investigate potential causal relationships, through the use of structural equation modeling (SEM), among tick counts (TC), Babesia bovis infection level (IB) and the gains in weight: from birth to adjusted weaning age (WG), and from weaning to yearling (YG). Statistical analyses were conducted in three steps: 1) Partition of (co) variances into genetic and residual components using Bayesian multiple-trait modeling (MTM); of 2) Search for plausible causal structures by applying the inductive causation (IC) algorithm to the residual (co)variances obtained in the first step; and 3) Final analysis using SEM, which was based on the causal network learned from the IC algorithm. The most plausible results comprised three direct links between traits: WG -> YG, TC -> WG, and WG -> IB with structural coefficients posterior means equal to -0.3026, 6.3620, and 0.0004, respectively. The final inferred directed acyclic graph (DAG) suggests that interventions on TC would directly affect WG, which would then affected YG; moreover, WG could also present a small positive effect on IB. (AU)

• FAPESP's process: 15/13024-0 - Genomic study on infection rate of Babesia bovis and association with resistance of tick in Hereford and Braford cattle
• Grantee: Ligia Cavani
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 17/08940-3 - Study of phenotypic causal networks of Babesia bovis, tick resistance and body weights at different ages in Hereford and Braford cattle using structural equation model
• Grantee: Ligia Cavani
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 16/07216-7 - Genomic study and immunological characterization of cattle resistant to bovine babesiosis and analysis of the genetic diversity of Babesia bovis and Babesia bigemina
• Grantee: Henrique Nunes de Oliveira
• Support Opportunities: Research Projects - Thematic Grants