The effect of grain supplementation on alpaca (Vicugna pacos) production and meat quality

Abstract

The objective of this study was to determine the effects of grain supplementation on alpaca production and meat quality, from animals raised under a pasture based system in Australia. A total of 56 castrated male alpacas were randomly assigned to one of eight groups (n=7 per group). The eight groups represented two nutritional treatments (pasture-only or pasture+grain supplementation), with each treatment having four replicates. Supplemented animals were incrementally introduced to the ration over a two week period and fed a total grain ration (calculated on 300g/animal/day fed on a paddock basis to reflect commercial feeding) for 8 weeks prior to slaughter. The ration was comprised of whole oats, rolled barley, cracked lupins, cracked corn, black sunflower seeds plus an oil and mineral premix. There was a similar pasture base across all treatments. Supplemented animals displayed larger weight gains (0.64kg/week) across the experiment in comparison to pasture-only animals (0.54kg/week). Although not statistically significant, supplemented animals generated on average, larger eye muscle areas (26cm2 compared to 25cm2) and higher percentages of intra muscular fat (IMF) in the m. longissimus thoracis et lumborum (0.76% compared to 0.67%). Supplementation had minimal effect on fatty acids profiles, including health claimable fatty acids and total omegas. This is likely due to the ration being fed to complement a pasture based system, which is typical for this industry, rather than if it was a substitution ration which would reflect a more intensive system. Overall, grain supplementation was found to increase alpaca production (growth rate) without compromising any of the health benefits associated with this red meat product. The evidence in this study suggests that increasing IMF content of alpaca meat, particularly in m. biceps femoris, will enhance health claimable fatty acid levels within alpaca meat. Greater differences between nutritional treatments would be expected during less favourable pasture conditions such as when pasture is limited due to unfavourable environmental conditions and below average rainfall leading to drought.