The objective of the study was to evaluate the phenotypic variability of the percentage of medullated fibres of Huacaya alpacas, as well as to calculate the phenotypic correlation between the average diameter of fiber (ADF) and the percentage of total medullation (PM). Fibre samples were collected from 36 Huacaya alpacas (0.4-10.4 years old males) to analyse the ADF and the PM with the projection microscope. The type of medulla of the fibres was considered as not medullated, fragmented, discontinuous, continuous and strongly medullated. A high phenotypic variability of PM between alpacas and within the samples was observed. The mean ± standard deviation of PM and ADF was 32.56 ± 18.30% and 17.58 ± 2.52 μm for non-medullated fibres; 29.29 ± 11.67% and 21.49 ± 2.39 μm for fragmented medullated fibres; 14.01 ± 10.14% and 24.04 ± 2.40 μm for discontinuous medullated fibres; 23.90 Â...

            The aim of this study was to evaluate the effect of the age and sex of the vicuña on the mean fibre diameter (MFD), spinning fineness, curvature index, fibre length and fibre diameter profile; also, to calculate the phenotypic correlations between fibre textile characteristics. Pre-dehaired samples (n=88) were analysed with the OFDA 2000 equipment. In the statistical model the age, sex and age:sex interaction were considered as fixed effects. Sex had a significant effect on the phenotypic variations of DMF, maximum and minimum diameter profile; likewise, age had a significant effect on MFD, spinning fineness and minimum profile diameter. However, the interaction of sex and age had no effect on the characteristics studied. The phenotypic correlations were significant and positive between DMF and spinning fineness, spin fi...

In alpacas color fleece phenotypes have different terminologies that induces confusion within the brown color and its shades, it requires a better description and quantification. Consequently, the aims of the study were to quantify the color of fiber and identify the informational SNPs in the MC1R gene (melanocortin 1 receptor) in brown and black alpacas. A vicuña phenotype (n=14) and four alpaca phenotypes (n=79), light brown, dark brown, brown-black and black were evaluated by colorimetry. The vicuña fleece showed greater lightness (47.74) and color intensity (24.33) compared to brown alpacas. The CIE L*a*b* values (lightness and intensity) suggest low values in eumelanic alpacas and high in pheomelanic alpacas. In vicuña and alpaca, the coding sequence of the MC1R gene has a single exon of 954 bp, in vicuñas the deletion (c.224_227del) was not observed. However, this deletion was ...

In alpacas color fleece phenotypes have different terminologies that induces confusion within the brown color and its shades, it requires a better description and quantification. Consequently, the aims of the study were to quantify the color of fiber and identify the informational SNPs in the MC1R gene (melanocortin 1 receptor) in brown and black alpacas. A vicuña phenotype (n=14) and four alpaca phenotypes (n=79), light brown, dark brown, brown-black and black were evaluated by colorimetry. The vicuña fleece showed greater lightness (47.74) and color intensity (24.33) compared to brown alpacas. The CIE L*a*b* values (lightness and intensity) suggest low values in eumelanic alpacas and high in pheomelanic alpacas. In vicuña and alpaca, the coding sequence of the MC1R gene has a single exon of 954 bp, in vicuñas the deletion (c.224_227del) was not observed. However, this deletion was ...

The aim of this study was to determine the correlation between the staple strength and the textile characteristics of black and brown fibres, as well as to evaluate the influence of colour, breed, location, age, and sex of alpaca on the staple strength properties. Staple strength was measured with the Staple Length & Strength instrument. Fibre characteristics were measured using an Optical-based Fibre Diameter Analyzer (OFDA 2000). Data did not show a normal distribution, as verified by the Shapiro-Wilk normality test. Spearman’s rank correlation coefficients between staple strength and fibre textile characteristics were calculated. The influence of colour, breed, location, age, and sex of alpacas on the staple strength properties were analysed separately by the Kruskal-Wallis rank sum test (α=0.05). The highest correlation was observed between peak force position and staple lengt...

The objective of the study was to evaluate the phenotypic variability of the percentage of medullated fibres of Huacaya alpacas, as well as to calculate the phenotypic correlation between the average diameter of fiber (ADF) and the percentage of total medullation (PM). Fibre samples were collected from 36 Huacaya alpacas (0.4-10.4 years old males) to analyse the ADF and the PM with the projection microscope. The type of medulla of the fibres was considered as not medullated, fragmented, discontinuous, continuous and strongly medullated. A high phenotypic variability of PM between alpacas and within the samples was observed. The mean ± standard deviation of PM and ADF was 32.56 ± 18.30% and 17.58 ± 2.52 μm for non-medullated fibres; 29.29 ± 11.67% and 21.49 ± 2.39 μm for fragmented medullated fibres; 14.01 ± 10.14% and 24.04 ± 2.40 μm for discontinuous medullated fibres; 23.90 Â...

            The aim of this study was to evaluate the effect of the age and sex of the vicuña on the mean fibre diameter (MFD), spinning fineness, curvature index, fibre length and fibre diameter profile; also, to calculate the phenotypic correlations between fibre textile characteristics. Pre-dehaired samples (n=88) were analysed with the OFDA 2000 equipment. In the statistical model the age, sex and age:sex interaction were considered as fixed effects. Sex had a significant effect on the phenotypic variations of DMF, maximum and minimum diameter profile; likewise, age had a significant effect on MFD, spinning fineness and minimum profile diameter. However, the interaction of sex and age had no effect on the characteristics studied. The phenotypic correlations were significant and positive between DMF and spinning fineness, spin fi...

El objetivo del estudio fue determinar el porcentaje de fibras meduladas (PFM), diámetro medio de fibra (DMF), desviación estándar de DMF (DE), coeficiente de variación de DMF (CV), porcentaje de fibras menores a 30 µm (FC), finura al hilado (FH), índice de curvatura (IC) y longitud de fibra según el lugar de procedencia de la vicuña, sitio de muestreo de fibra, edad y sexo. Se recolectaron 228 muestras de fibra de tres sitios corporales de 82 vicuñas (hembras y machos) procedentes de cuatro rebaños de Apurímac y uno de Ayacucho. Para el análisis estadístico se consideró como efectos fijos: sitio de muestreo de fibra, lugares de procedencia de la vicuña, edad, sexo y la interacción doble. La comparación múltiple de medias se determinó mediante la prueba de Tukey (α=0.05) y se utilizó el análisis de regresión simple para predecir el PFM. Según la procedencia de las...

El objetivo de este estudio fue evaluar la presencia de caspa en la vicuña y su influencia en seis características textiles principales de la fibra de vicuña según sitio de muestreo, edad y sexo. En el modelo lineal se incluyeron cuatro factores: caspa, edad, sexo y sitio de muestreo del vellón. El estudio reveló una alta prevalencia de caspa, 20.55% en 2017 y 22.97% en 2021. La caspa comienza en la cabeza y se extiende a la parte inferior del cuello, línea dorsal, paleta y costillar medio. Se observó una reducción signi-ficativa del diámetro medio de fibra (DMF) en vicuñas adultas y hembras con caspa. En los sitios del costillar y grupa, el DMF fue más fino y homogéneo, excepto en la parte inferior del cuello, barriga, paleta y muslo, donde la fibra mostró una tendencia a engro-sarse. Además, la caspa reduce significativamente el DMF en la parte inferior del cuello, costi...

The aim of this research was to compare vicuña fibre by the Fourier transform infrared (FTIR) spectroscopy, determine the colorimetric parameters and the percentages of medullation in vicuña fibre from Puno and Apurímac (Peru). Luminosity (L*), colour intensity or purity (C*) and hue (H*) were characterized by colorimetry. These parameters demonstrate a variability of colour and tonality in the vicuña fleece. The FTIR spectra in fibre from vicuñas from Puno and Apurimac overlap, confirming a similar chemical profile in the fibre structure. The percentage of total medullation is different according to the origin, where the vicuñas of the Community of Toma (Puno) have higher percentage of medulation (5.02%), while the vicuñas of the communities of Pilluni (1.65%) and Taraccasa (1.80%) of Apurimac maintain a lower percentage of medullation. Likewise, variability in the percentage of ...

El objetivo de la investigación fue determinar la variación de las características textiles y longitud de fibra al descerdado manual del vellón de vicuña, así como evaluar la influencia del sexo, edad, sitio de muestreo del vellón, y lugar de procedencia de la vicuña sobre las características de calidad de la fibra. El descerdado manual se realizó en 77 muestras de vicuñas provenientes de tres provincias del departamento de Apurímac, Perú. Las características textiles de la fibra antes y después del descerdado fueron evaluadas usando el equipo OFDA 2000 y mediante el análisis de varianza, prueba de t y Tukey (α=0.05). La calidad de fibras descerdada es superior a la fibra no descerdada, debido a la reducción del diámetro medio de fibra (DMF) (-1.68 μm), desviación estándar de DMF (DE) (-0.73) y finura al hilado (FH) (-1.27 μm) y al incremento del porcentaje de fibr...

The aim of this study was to determine the bleaching time of the black and brown fibre with hydrogen peroxide and to evaluate the percentage of medullated fibres according to colour and sampling site in the Huacaya alpaca fleece. In total, 90 fibre samples (shoulder, mid-side area, and rump) were taken from 30 alpacas (10 black, 10 brown, and 10 white). The fibre (2 g) was bleached at different times (5-105 min) with 20 g hydrogen peroxide (40 volume oxygenated cream) and 10 g bleaching powder (High lift 9 Tones). The colorimetric coordinates (L*a*b*) were evaluated at 5, 10, 35, 70 and 105 min in black fibre and at 35 and 70 minutes in brown fibre. After the microscopic analysis, fibre medullation percentage and their standard error were calculated. The luminosity in black fibre is low (5.19 ± 1.78), which increases with bleaching time to 86.60 ± 1.49 at minute 105. The luminosity in ...

The aim of the study was to evaluate the variability of the percentage of medullated fibres, according to sex and location and to compare the colorimetric characteristics in white fibre from Huacaya and Suri alpaca. The study was carried out in two communities (Juntaya in the Oropesa district and San Juan in the Sabaino district) in the province of Antabamba, Apurímac region (Peru), located between 3950 and 4543 meters above sea level. In total, 451 (Huacaya = 410 and Suri = 41) fibre samples (10 g) were taken from the mid side area. The medullated fibres (%) and the mean fibre diameter (µm) were evaluated using the Fiber Med device. For the colour analysis, a spectrometer coupled to an integrating sphere was used and for the characterization of the chemical bands, an FTIR spectrophotometer. The percentage of total medullation, continuous medullation and strongly medullated fibres were...