- Over the years I have operated AAFT, the question of whether to use Standard Deviation (SD) or Co-efficient of variation (CV) when evaluating fibre traits is undoubtedly one of the most commonly asked questions. It also happens to be one of the issues most plagued by misunderstanding, and consequently, carries the potential to de-rail breeding strategies, particularly those aimed at reducing the incidence of coarse fibres, increasing the level of fibre uniformity, improving the processing performance of fleeces or simply improving the style and handle of fleeces. more »
- Since about 2008, the Australian alpaca fleece market has moved from a single desk marketing system dominated by the Australian Alpaca Fleece Ltd, to competitive supply networks incorporating a number of fleece collection and buying entities. The entities range from producer based collectives to commercial businesses. Further, these entities are able to adopt any one, or a combination of fleece collection protocols or standards that have been developed over recent years to provide guidance on how to class alpaca fleeces into commercially driven consignment lines. more »
- Increasing the knowledge of the semen characteristics in the alpaca will contribute to understanding one of the many factors that affect the poor fertility rate in this species. Ten adult male alpacas, 2.6–10 years of age, average weight 64.7±4.7 kg were used. The animals were distributed randomly into two groups of five each and submitted alternatively to two semen collections, using an artificial vagina and sexually receptive females. For the first semen collection the animals had a sexual rest period of about 90 and 45 days before the second. Duration of semen collection, color and volume of ejaculate were recorded, and sperm concentration and morphology (light microscopy) were evaluated. Descriptive statistical analyses were used for each variable, considering all samples obtained (n=19). An analysis of variance for animal groups and opportunity of collection were used for quantitative variables. Most frequent color was opalescent white (84.2%). There were no statistical differences among male groups or between semen collections. The average values and standard deviations for the quantitative variables were: 12.3±7.2 min for semen collection time, 1.8±0.8 ml for ejaculate volume, (17.6±26.1)×106 sperm/ml for sperm concentration and 34.0±52.2×106 for total number of sperm per ejaculate. The percentage of normal spermatozoa was 51.0±12.4%. From the total abnormalities, that of mid piece segment (14.4%) was the most frequent. These results indicate that male alpaca have poor semen quality, when compared with other domestic species. Nevertheless, for the evaluation of male alpaca as breeders it would be necessary to create a protocol for the selection of them, where phenotypic, behavioral and seminogram aspects are considered. The values reported herein define the characteristics of the alpaca semen that could be considered as the initial base of the seminal analysis to select male alpacas before mating. more »
- The usefulness of classifying the Alpaca wool samples according to their color, sex and location is associated with their economic value in the market, hence adequate methods for rapid classification are needed to assess the of wool value. This study evaluated the potential of the visible and near infrared (vis-NIR) spectroscopy combined with multivariate statistical analysis to classify Alpaca (Lama Pacos) fiber samples according to age (1 and 2-3-year-old), sex (Male and Female) and color (Black, Brown, LF and White). Samples (n=291) were scanned in reflectance mode in the wavelength range of 400-2500nm using a monochromator instrument (FOSS NIRSystems6500, Inc., Silver Spring, MD, USA). Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used to classify fiber samples. Cross-validation was used for validation of classification models developed. Results showed that PLS-DA correctly classified 100% of fiber samples into ages, intermediate classification rates were obtained for color, while lower classification rates were obtained for the discrimination of wool samples according to sex. The results from this study suggested that vis-NIR spectroscopy in combination with multivariate data analysis can be used as a rapid method to classify Alpaca fiber samples according to age, sex and color. more »
- The aim of this study was to determine the relationship between selenium (Se) concentration (which is used as direct method for diagnostics of selenium status) and activity of glutathione peroxidase (indirect method) in whole blood of alpacas and thus compare the suitability of use of these two diagnostic methods. A further objective was to determine Se status in relation to different age groups of alpacas and different Se supplementation. A total of 257 alpacas (196 adults and 61 crias) from 18 farms were included in this study. The farms differed in size and the use of Se supplement. The age of animals ranged from 4 days up to 16 years old. Blood samples were collected for measurement of whole blood Se concentration and glutathione peroxidase (GSH-Px) activity. The activity of GSH-Px is given in μkat/l of whole blood and μkat/g of hemoglobin. The relation between concentration of Se and GSH-Px activity and the effect of sex, age and feeding pattern on these parameters were statistically evaluated. Mean (±SD) Se concentration was 84.1 ± 35.3 μg/l and ranged from 27.9 μg/l to 225.6 μg/l for all age groups. We found significant difference (P more »