Data/hora: 19/06/2024 08:38:49

Biblioteca(s): 	Embrapa Pecuária Sudeste; Embrapa Pecuária Sul; Embrapa Recursos Genéticos e Biotecnologia.	
Data corrente: 	17/11/2020	
Data da última atualização: 	17/11/2020	
Autoria: 	CAVANI, L.; BRAZ, C. U.; GIGLIOTI, R.; OKINO, C. H.; GULIAS GOMES, C. C.; CAETANO, A. R.; OLIVEIRA, M. C. de S.; CARDOSO, F. F.; OLIVEIRA, H. N. de.	
Afiliação: 	LIGIA CAVANI, UNESP; CAMILA URBANO BRAZ, UNESP; RODRIGO GIGLIOTI, Instituto de Zootecnia; CINTIA HIROMI OKINO, CPPSE; CLAUDIA CRISTINA GULIAS GOMES, CPPSUL; ALEXANDRE RODRIGUES CAETANO, Cenargen; MARCIA CRISTINA DE SENA OLIVEIRA, CPPSE; FERNANDO FLORES CARDOSO, CPPSUL; HENRIQUE NUNES DE OLIVEIRA, UNESP.	
Título: 	Genomic study of Babesia bovis infection level and its association with tick count in Hereford and Braford cattle.	
Ano de publicação: 	2020	
Fonte/Imprenta: 	Frontiers in Immunology, v. 11, article 1905, aug. 2020.	
Páginas: 	11 p.	
DOI: 	https://doi.org/10.3389/fimmu.2020.01905	
Idioma: 	Inglês	
Conteúdo: 	Bovine babesiosis is a tick-borne disease caused by intraerythrocytic protozoa and leads to substantial economic losses for the livestock industry throughout the world. Babesia bovis is considered the most pathogenic species, which causes bovine babesiosis in Brazil. Genomic data could be used to evaluate the viability of improving resistance against B. bovis infection level (IB) through genomic selection, and, for that, knowledge of genetic parameters is needed. Furthermore, genome-wide association studies (GWAS) could be conducted to provide a better understanding of the genetic basis of the host response to B. bovis infection. No previous work in quantitative genetics of B. bovis infection was found. Thus, the objective of this study was to estimate the genetic correlation between IB and tick count (TC), evaluate predictive ability and applicability of genomic selection, and perform GWAS in Hereford and Braford cattle. The single-step genomic best linear unbiased prediction method was used, which allows the estimation of both breeding values and marker effects. Standard phenotyping was conducted for both traits. IB quantifications from the blood of 1,858 animals were carried using quantitative PCR assays. For TC, one to three subsequent tick counts were performed by manually counting adult female ticks on one side of each animal's body that was naturally exposed to ticks. Animals were genotyped using the Illumina BovineSNP50 panel. The posterior mean of IB heritability, estimated by the Bayesian animal model in a bivariate analysis, was low (0.10), and the estimations of genetic correlation between IB and TC were also low (0.15). The cross-validation genomic prediction accuracy for IB ranged from 0.18 to 0.35 and from 0.29 to 0.32 using k-means and random clustering, respectively, suggesting that genomic predictions could be used as a tool to improve genetics for IB, especially if a larger training population is developed. The top 10 single nucleotide polymorphisms from the GWAS explained 5.04% of total genetic variance for IB, which were located on chromosomes 1, 2, 5, 6, 12, 17, 18, 16, 24, and 26. Some candidate genes participate in immunity system pathways indicating that those genes are involved in resistance to B. bovis in cattle. Although the genetic correlation between IB and TC was weak, some candidate genes for IB were also reported in tick infestation studies, and they were also involved in biological resistance processes. This study contributes to improving genetic knowledge regarding infection by B. bovis in cattle.	
Palavras-Chave: 	Bovine babesiosis; Cross validation; Genetic parameters; Genome wide association studies; Genomic selection.	
Thesagro: 	Babesia Bovis.	
Categoria do assunto: 	H Saúde e Patologia	
URL: 	http://ainfo.cnptia.embrapa.br/digital/bitstream/item/217858/1/GenomicStudyBabesia.pdf	
Registro original: 	Embrapa Pecuária Sudeste (CPPSE)	
Exemplares: 	CPPSE - (25145-1) - UPC - AP - DD - PROCI-2020.00062 - CAV - 2020.00113 - DIS
CENARGEN - (38328-1) - UPC - AP - DD -  -  -  - DIS
CPPSUL - (14717-1) - UPC - AP - DD -  -  -  - DIS