Meta-analysis study of the genetic parameters of fiber traits in Cashmere goats

By aggregating the previous studies, the present study aimed to perform a meta-analysis to estimate the weighted average of the genetic parameters of fiber length, fiber diameter and percentage yield of fiber in cashmere goats to increase the accuracy of estimations. The data of 14 related published papers between 1989 and 2021 were used. A model with random effects was used to estimate the genetic parameters, standard error and 95% confidence range of traits by using Metafor package in R environment. The weighted average of heritability estimates for length, diameter and percentage yield were 0.24 ± 0.047, 0.42 ± 0.053 and 0.60 ± 0.103, respectively. The obtained results indicated that the studied traits have high heritability estimates and therefore the direct genetic selection can lead to the improvement of the performance of these traits. The highest estimate of genetic and phenotypic correlations were obtained between the percentage yield and the fiber length as 0.84 and 0.54, respectively. The lowest genetic and phenotypic correlations were obtained between the percentage yield and the fiber diameter as 0.38 and 0.35, respectively. Sharp reductions in the standard errors of the heritability estimates due to aggregating the results and increasing the sample size, improve accuracy of the corresponding estimates. The genetic parameters estimated in the present study may be used for developing the breeding programs to improve the fiber traits in Cashmere goats. Therefore, the results of meta-analysis study can improve the breeding programs, especially in breeds with insufficient records.