Genetic parameters for fleece weight and fibre attributes in Argentinean Llamas reared outside the Altiplano

Abstract

The objective of this work with Argentinean Llamas was to estimate (co)variance components and genetic and permanent environmental parameters and to report mean and standard deviations of fleece weight and fibre attributes, measured under outside Altiplano areas conditions. A total of 2850 records, from 450 founder females and 45 founder males allowed the measurement of 816 animals. The animals came from 3 different localities and the fleece variables were: fleece weight (under annual shearing) (FW, kg), fleece strip weight (as fleece weight predictor) (FSW, g), staple length (SL, cm), mean fiber diameter (MFD, μm), fiber diameter coefficient of variation (FDCV, %), total medulation grades (MG, %) and lattice medulla fibre (CFP,%); Chest circumference (CC, cm) was used as a predictor for animal size. Residual, genetic and permanent environmental (co)variances were obtained through a multivariate Animal Model with repeatibilities, using VCE4 software. Mixed model fixed effects include: year of production, year of sampling (repeated), animal age classed at sampling, flocks, coat color and type of fleeces and CC as linear covariate. The estimated heritabilities were: 0.44 ± 0.05 (FW), 0.34 ± 0.06 (FSW), 0.23 ± 0.05 (SL), 0.32 ± 0.05 (MFD), 0.33 ± 0.06 (FDCV), 0.29 ± 0.04 (MG), and 0.33 ± 0.07 (CFP). Genetic correlations were significant ( p < 0.05) for all pairs of variables with the exception of FW–FDCV and MFD–FDCV. All correlations level were medium to high, but FW–FSW was very high (0.89 ± 0.04), showed that both attributes are almost identical. Repeatibilities were high for all attributes, and all permanent environment effects were statistically significant ( p < 0.05). The heritabilities, repeatibilities and correlations obtained in this work were generally lower than other values out of the Altiplano areas, but in concordance with similar values from Altiplano. It can be concluded that there are large opportunities to improve the fibre diameter and fibre diameter variation, and also fibre production attribute if this are chosen as selection criteria. The fleece strip weight variable is important as fleece weight predictor because of the high genetic and phenotypic correlation between them. The implication of this work is grounded on the use of genetic parameters to generate a selection program outside Altiplano (highlands) conditions and under production systems in the hands of small peasants.