The aim of this study was to estimate the genetic parameters (heritability and genetic correlations) for characters associated with the uniformity of fibre diameter in fleece of young (tuis) alpacas of the Mallkini farm (Puno, Peru). Samples were taken from the thigh, mid-rib and shoulder of 1127 animals at the first shearing (573 males and 554 females) born in 2015 and 2016. The samples were analysed under the IWTO-12 standard of the Sirolan Laserscan equipment. The pedigree file had 10 481 alpacas giving a coefficient of inbreeding of 0.16%. The genetic parameters were estimated using ASReml and Pedigree Viewer software. The characters evaluated were the fibre diameter and its standard deviation, coefficient of variation and comfort factor. The genetic analysis was carried out using a multivariate animal model, which includes the additive genetic effect of the animal as a random e...

El objetivo del presente estudio fue estimar los parámetros genéticos (heredabilidad y correlaciones genéticas) para caracteres asociados a la uniformidad del diámetro de fibra en el vellón de alpacas tuis del fundo Mallkini (Puno, Perú). Se utilizaron muestras de las zonas corporales de muslo, costillar medio y paleta de 1127 animales a la primera esquila (573 machos y 554 hembras) nacidos en 2015 y 2016. Las muestras fueron analizadas bajo la norma IWTO-12 del equipo Sirolan Laserscan. El archivo de pedigrí contaba con 10 481 alpacas dando un coeficiente de consanguinidad de 0.16%. Los parámetros genéticos se estimaron mediante los softwares ASReml y Pedigree Viewer. Los caracteres evaluados fueron el diámetro de fibra (DF) y su desviación estándar (DE), coeficiente de variación (CV) y factor de confort (FC). El análisis genético se realizó utilizando un modelo ani...

The aim of this study was to estimate genetic parameters for birth and weaning weight in guinea pigs (Cavia porcellus) reared in a farm in Cieneguilla, Lima, Peru. Univariate animal model that included sex of calf, parity, season of birth, animal and litter effect was used in the genetic analyses. In addition, the effect of number of newborns was included in the model for birth weight, and the number of born alive and age at weaning were included in the model for weaning weight. Variance components were estimated by Bayesian Gibbs sampling with a chain of100 000 rounds with the first 10 000 rounds discarded for burn-in by using MCMCglmm library of R software. Heritability estimates for birth weight was 0.155 ± 0.036 and for weaning weight was 0.246 ± 0.046. These values were similar to those estimated by using REML.

The aim of this study was to estimate genetic parameters for birth and weaning weight in guinea pigs (Cavia porcellus) reared in a farm in Cieneguilla, Lima, Peru. Univariate animal model that included sex of calf, parity, season of birth, animal and litter effect was used in the genetic analyses. In addition, the effect of number of newborns was included in the model for birth weight, and the number of born alive and age at weaning were included in the model for weaning weight. Variance components were estimated by Bayesian Gibbs sampling with a chain of100 000 rounds with the first 10 000 rounds discarded for burn-in by using MCMCglmm library of R software. Heritability estimates for birth weight was 0.155 ± 0.036 and for weaning weight was 0.246 ± 0.046. These values were similar to those estimated by using REML.

The purposes of this study were a) to evaluate the effect of random factors such as litter (L) and fixed effects such as season (S), calf sex (CS), and parity (P) on birth weight (BW) and weaning weight (WW); and b) to estimate the phenotypic correlation between BW and WW. The study was conducted in the Cieneguilla guinea pig farm of the Universidad Nacional Agraria La Molina. The data comprised 5460 and 3514 records for BW and WW respectively of improved guinea pigs. The data was collected from January 2009 to July 2010. Weaning was at 14 days of age. The feeding system was based on broccoli crop residues (Brassica oleracea italica) and concentrate. SAS MIXED procedure (v 9.1) was used to analyze the mixed models. Total born (TB) was used as covariate for BW and born alive (BA) and age of weaning (AW) were used as covariate for WW. BW was influenced (p<0.01) by TB, S, CS and P, and W...

The study was carried out at the Cieneguilla guinea pig farm of La Molina National Agrarian University, Lima. The objective of the study were to evaluate the association of fixed factors such as season (E), parity (NP), and covariates such as maternal weight at parity (PMP), total born (TN), number of live births (LB) and age at weaning (EDC) with total born (TN), number born alive (NV), number weaned (ND), litter weight at birth (PCN), and litter weight at weaning (PCD), and to estimate phenotypic correlations between the maternal traits. Data was collected from 1302 litters collected from January 2009 to July 2010. Analysis of variance and F tests were performed using the GLM procedure of SAS (v. 9.1). The statistical analysis for TN and NV adjusted for the covariate PMP differences were obtained for E and NP (p<0.01); for ND adjusted for the covariate PMP differences were obtained ...

Los objetivos del estudio fueron a) evaluar el efecto de factores al azar, como efecto de camada (C) y efectos fijos, como estación (E), sexo de la cría (SC), y número de parto de la madre (NP) sobre el peso al nacimiento (PNC) y peso al destete de las crías (PDC), y b) estimar la correlación fenotípica entre PNC y PDC. El estudio se desarrolló en la Granja de Cuyes de Cieneguilla de la Universidad Nacional Agraria La Molina. Se analizaron 5460 datos de PNC y 3514 datos de PDC recolectados de cuyes mejorados entre enero de 2009 a julio de 2010. El destete se realizó a los 14 días de edad en promedio. La alimentación fue en base a residuos de cosecha de brócoli (Brassica oleracea italica) y alimentos balanceados elaborados en la granja. Se utilizó el procedimiento MIXED de SAS (v 9.1) para el análisis de modelos mixtos. El total de nacidos (TN) se utilizó como covariable par...

The study was carried out at the Cieneguilla guinea pig farm of La Molina National Agrarian University, Lima. The objective of the study were to evaluate the association of fixed factors such as season (E), parity (NP), and covariates such as maternal weight at parity (PMP), total born (TN), number of live births (LB) and age at weaning (EDC) with total born (TN), number born alive (NV), number weaned (ND), litter weight at birth (PCN), and litter weight at weaning (PCD), and to estimate phenotypic correlations between the maternal traits. Data was collected from 1302 litters collected from January 2009 to July 2010. Analysis of variance and F tests were performed using the GLM procedure of SAS (v. 9.1). The statistical analysis for TN and NV adjusted for the covariate PMP differences were obtained for E and NP (p<0.01); for ND adjusted for the covariate PMP differences were obtained ...

Universidad Nacional Agraria La Molina. Escuela de Posgrado. Doctorado en Ciencia Animal

El objetivo del presente estudio fue evaluar el efecto de tres sistemas de alimentación sobre la respuesta productiva y el perfil de ácidos grasos en la carcasa de cuyes. Se emplearon 18 cuyes machos de 21 días de edad distribuidos aleatoriamente en tres grupos y alojados en jaulas galvanizadas. Los tratamientos fueron: T1, alfalfa verde; T2, alimentación mixta [alimento balanceado + alfalfa verde (10% del PV)]; y T3, alimentación integral (solo alimento balanceado). Se determinó la ganancia de peso, consumo de alimento y conversión alimenticia semanal. Los animales fueron sacrificados en el día 28 para evaluar el rendimiento de carcasa. Asimismo, se extrajo la grasa total para determinar el perfil de ácidos grasos mediante cromatografía de gases. Las variables de la respuesta productiva y el perfil de ácidos grasos de la carcasa de los animales experimentales fueron significa...

El objetivo del presente estudio fue evaluar el efecto de tres sistemas de alimentación sobre la respuesta productiva y el perfil de ácidos grasos en la carcasa de cuyes. Se emplearon 18 cuyes machos de 21 días de edad distribuidos aleatoriamente en tres grupos y alojados en jaulas galvanizadas. Los tratamientos fueron: T1, alfalfa verde; T2, alimentación mixta [alimento balanceado + alfalfa verde (10% del PV)]; y T3, alimentación integral (solo alimento balanceado). Se determinó la ganancia de peso, consumo de alimento y conversión alimenticia semanal. Los animales fueron sacrificados en el día 28 para evaluar el rendimiento de carcasa. Asimismo, se extrajo la grasa total para determinar el perfil de ácidos grasos mediante cromatografía de gases. Las variables de la respuesta productiva y el perfil de ácidos grasos de la carcasa de los animales experimentales fueron significa...

The alpaca herds in Pasco region, Peru, have few known genetic links, so the breeding value of sires from different herds cannot be compared since environmental effects can mask the genetic differences among them. The aim of the study was to evaluate a sire referencing scheme for a dispersed genetic nucleus of Huacaya alpacas in Pasco. Data was collected to evaluate the organizational capacity of the breeders and characterize the population structure of six herds belonging to the nucleus in 2016. The size of the nucleus was calculated based on the need for annual replacement of sires. The genealogy was simulated for three scenarios of sire reference schemes (SRS) with 3, 6 and 9 males mating 10, 20 and 30% of dams in the nucleus per generation respectively. The contemporary groups (CG) were determined by herd-year for three generations. Finally, the degree of the genetic link was calcula...

The alpaca herds in Pasco region, Peru, have few known genetic links, so the breeding value of sires from different herds cannot be compared since environmental effects can mask the genetic differences among them. The aim of the study was to evaluate a sire referencing scheme for a dispersed genetic nucleus of Huacaya alpacas in Pasco. Data was collected to evaluate the organizational capacity of the breeders and characterize the population structure of six herds belonging to the nucleus in 2016. The size of the nucleus was calculated based on the need for annual replacement of sires. The genealogy was simulated for three scenarios of sire reference schemes (SRS) with 3, 6 and 9 males mating 10, 20 and 30% of dams in the nucleus per generation respectively. The contemporary groups (CG) were determined by herd-year for three generations. Finally, the degree of the genetic link was calcula...