Examinando por Autor "Heredia Vilchez, Lizeth Amparo"

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Genetic diversity and structure of creole cattle (Bos taurus) from southern Peruvian Highlands
(2024-01-17) Figueroa Venegas, Deyanira Antonella; Saldaña, Carla L.; Corredor Arizapana, Flor Anita; Heredia Vilchez, Lizeth Amparo; Mamani Cato, Rubén Herberht; Gutierrez, Gustavo; Gomez Quispe, Oscar; Ciprian, Aldo; Murga Valderrama, Luis N.; Arbizu, Carlos I.
The creole cattle was originated after the introduction of cattle into America 5 centuries ago. Currently, the production traits of Peruvian creole cattle is scarcely known. An important characteristic of the creole cattle is its adaptability to different extreme environments. However, to date, molecular studies in Peruvian creole cattle are still scarce. Currently, due to the advances in molecular genetics, a new generation of molecular markers has been developed for the genetic characterization of livestock. Single nucleotide polymorphisms (SNP) have become a very popular tool for the genetic study of livestock populations. Genome-wide SNP chips were developed for multi-breed genetic studies in cattle.
Influence of agroclimatic factors on the efficiency of multi-ovulation in cattle in the Peruvian tropics
(Frontiers Media S.A., 2025-04-01) Segura Portocarrero, Gleni Tatiana; Murga Valderrama, Nilton Luis; Lopez Lapa, Rainer Marco; Saucedo Uriarte, José Américo; Gongora Bardales, Deiner Jhonel; Frias Torres, Hugo; Poclín Rojas, Annie Yoselin; Depaz Hizo, Benjamin; Vasquez Tarrillo, Ronald Will; Heredia Vilchez, Lizeth Amparo; Ampuero Trigoso, Gustavo
Introduction: Agroclimatic conditions are key determinants in the development of animal production and reproduction, with specific breed differences in vulnerability to environmental stress. This research aims to determine the influence of agroclimatic factors on the efficiency of multi-ovulation in cattle in the Peruvian tropics. Methods: The study was conducted at the “El Porvenir” Agricultural Experimental Station (EEA) of the National Institute of Agricultural Innovation (INIA), located in the district of Juan Guerra, province and department of San Martín, Peru. Throughout a year, four collections of structures were made from 12 Bos indicus donor cows from the genetic nucleus of the PROMEG Tropical project every 2 months under intensive breeding conditions. The cows were classified according to their production: milk (five individuals of the Gyr breed and two of the Guzerat breed) and meat (two individuals of the Nelore breed and three of the Brahman breed), with ages of 3 and 4 years, selected based on specific criteria: regular estrous cycles, no deformities or reproductive problems, and certified pedigree registration. During each collection protocol, the number of viable structures (blastocysts and morulas), non-viable structures (unfertilized oocytes-UFO and degenerated), and agroclimatic factors [temperature (°C), relative humidity (%), precipitation (mm), wind speed (m/s), and the Temperature-Humidity Index (THI)] were evaluated at three times (6 a.m., 1 p.m., and 6 p.m.). A longitudinal experimental design was used for the analysis. Statistical tests were applied, including ANOVA and post-hoc tests (Tukey's Test), to assess the significance of differences between variables, such as the humidity index and temperature in relation to the production of viable structures and non-viable structures. Data visualization was achieved using R Studio libraries, including ggplot2, factoextra, and FactoMineR. Results: The analyses highlight the influence of the interaction between humidity and temperature, resulting in THI on bovine stress, revealing complex interactions that primarily affect embryo production. Stress peaks, especially under adverse conditions, were observed to significantly impact animal health. Discussion: This response to stress can affect both overall well-being and productive performance. Additionally, it should be noted that this impact varies according to the adaptability and resilience of the breed. Therefore, it is suggested to continue this study, as the literature on this topic is limited, and to conduct further research to optimize the well-being and productivity of livestock.
Microsatellite-based genetic diversity and population structure of Huacaya alpacas (Vicugna pacos) in Southern Peru
(MDPI, 2023-05-05) Figueroa Venegas, Deyanira Antonella; Corredor Arizapana, Flor Anita; Mamani Cato, Ruben; Gallegos Acero, Roberto; Condori Rojas, Nicoll; Estrada Cañari, Richard; Heredia Vilchez, Lizeth Amparo; Salazar Coronal, Wilian; Quilcate Pairazamán, Carlos Enrique; Arbizu Berrocal, Carlos Irvin
The alpaca population mostly consists of the Huacaya phenotype and is widely distributed in Southern Peru. This study aimed to estimate the genetic diversity and population structure of two Huacaya alpaca populations (Ajoyani and Quimsachata) using fourteen and twelve microsatellite markers for each population, respectively. A total of 168 alpaca biological samples were outsourced to Peruvian laboratories for DNA extraction and genotyping. For genetic diversity, observed heterozygosity (Ho), expected heterozygosity (He), polymorphism information content (PIC), and fixation indices values were estimated. An admixture analysis was performed for the population structure analysis. Different programs were used for these estimations. In total, 133 (Ajoyani) and 129 (Quimsachata) alleles were found, with a range of 4 to 17 by locus. The mean HO, HE, and PIC per marker for Ajoyani were 0.764 ± 0.112, 0.771 ± 0.1, and 0.736; for Quimsachata, they were 0.783 ± 0.087, 0.773 ± 0.095, and 0.738, respectively. The population structure showed no structure with K = 2. This study provides useful indicators for the creation of appropriate alpaca conservation programs.