Rumen‐protected methionine supplementation and fibre production in alpacas (Vicugna pacos)

Abstract

Sulphur-containing amino acids are a crucial requirement for fibre production and may be supplemented in the diet of fibre-producing animals to stimulate fibre growth. The alpaca fibre industry is a developing industry in Australia with high variability in fibre production. To date, there is no evidence whether supplementing the diet of alpacas with sulphur amino acids improves fibre production. We hypothesised that supplementation with the rumen-protected sulphur amino acid, methionine would increase fibre growth in alpacas. Three groups of eight huacaya alpaca wethers were fed daily a maintenance diet supplemented with 0, 2 or 4 g of rumen-protected methionine for 7 weeks. Fibre samples were taken at the beginning and end of the study with a blood sample taken by jugular venipuncture prior to feeding on the first day of each week. Methionine supplementation had no effect on fibre diameter (p = 0.92), fibre length (p = 0.91) or fibre yield (p = 0.33). The change of season over the study affected plasma glucose (p < 0.001), plasma urea nitrogen (p < 0.001) and fibre diameter (p < 0.001). The indifference between groups may be due to the maintenance diet supplying sufficient levels of methionine, the lack of genetic potential of the experimental animals to respond to additional methionine or that the supplemental methionine was not protected in alpacas and deaminated for glucose production.

Textile characteristics of fiber from Huacaya alpacas (Vicugna pacos)

“…Alpaca farming allows extensive natural pastures, which are otherwise unsuitable for crops or other livestock, to be productive (Iñiguez and Alem, 1996). Alpacas have adapted to available dietary resources in areas where they are raised (Li et al, 2008) and thus are productive even in the absence of nutritional supplementation (Moore et al, 2012). Among South American camelids, alpacas were domesticated more than 6,000 years ago (Wheeler, 2004) and have been used for fiber production for more than 3,000 years (Wang et al, 2003;Wuliji et al, 2000).…”