Genetic diversity in Brown Swiss cattle from Azangaro province, Puno region, Peru
The aim of this study was to evaluate the genetic diversity and population structure of the mitochondrial cytochrome b (cytb) gene in Brown Swiss cattle raised in the Peruvian highlands. Blood samples were collected from 41 cows belonging to 13 dairy farms in Azángaro province, Puno Region. After DN...
Guardado en:
| Autores principales: | , , |
|---|---|
| Formato: | Artículo revista |
| Lenguaje: | Español |
| Publicado: |
Universidad Nacional del Nordeste
2026
|
| Materias: | |
| Acceso en línea: | https://revistas.unne.edu.ar/index.php/vet/article/view/9224 |
| Aporte de: |
| Sumario: | The aim of this study was to evaluate the genetic diversity and population structure of the mitochondrial cytochrome b (cytb) gene in Brown Swiss cattle raised in the Peruvian highlands. Blood samples were collected from 41 cows belonging to 13 dairy farms in Azángaro province, Puno Region. After DNA extraction and PCR amplification, Sanger sequencing was performed. Prior to bioinformatics analysis, three sequences were excluded due to low quality (Q-score < 20), resulting in a final dataset of 38 sequences. Alignment was conducted using the MUSCLE algorithm, and phylogenetic reconstruction was performed using the Maximum Likelihood method (HKY+I model) in MEGA v.12. Genetic diversity indices were estimated using R. A total of 31 distinct haplotypes were identified, indicating high haplotype diversity (Hd = 0.9687) combined with low nucleotide diversity (π = 0.0240). The haplotype network exhibited a star-like topology, characterized by a high number of unique haplotypes and a few central ones. Tajima's Neutrality Test yielded consistently negative values (D < -2.5), suggesting an excess of low-frequency polymorphisms, which is consistent with a recent population expansion or purifying selection. Phylogenetic analysis revealed the presence of multiple divergent mitochondrial lineages without a clear geographic structure. These results indicate that, despite being a commercial breed, the Brown Swiss population in northern Puno retains considerable and heterogeneous mitochondrial genetic reserve, likely maintained through active gene flow. This genetic variability represents an important resource for the design of sustainable conservation and genetic improvement strategies in the region. |
|---|