The guts of alpaca nutrition: understanding energy and protein metabolism

[Truncated abstract] Alpacas are unique animals in terms of their digestive capabilities and energy and protein metabolism. Nutritional information pertaining to alpacas has been extrapolated from data based on true ruminant nutritional requirements and is therefore inaccurate and misleading for alpaca producers. The general hypothesis tested in this thesis was that alpacas would be better at utilising feedstuffs and be more efficient at obtaining glucose and amino acids that are essential for both maintenance and fibre production than sheep. Two experiments in this thesis (Chapters 3 and 5) evaluated the potential of using un-degradable dietary protein (UDP) in alpaca diets as a means of optimising fibre growth. Chapter 4 of this thesis reports a training method and the design of a special metabolism pen for alpacas which was developed to conduct the experiments described in Chapters 5 and 7. The next experiment (Chapter 6) determined whether alpacas could utilise calcium propionate as a source of glucose. The last experiment (Chapter 7) examined how intakes of different proportions of energy and protein influenced nitrogen metabolism in alpacas compared to sheep. The hypothesis tested in Chapter 3 was that alpacas fed a diet containing canola meal high in UDP to meet maintenance requirements would produce more fibre and spend less time urinating than peers fed a similar amount of canola meal with a low proportion as UDP. Alpacas were fed diets of similar metabolisable energy (ME) content at a level calculated to maintain body weight with the following ratios of UDP: rumen degradable dietary protein (RDP); 0:100 (0% UDP), 30:70 (30% UDP), 60:40 (60% UDP) or 100:0 (100% UDP) from canola meal protein. The fibre characteristics of the alpacas were analysed to determine whether fibre production was affected by the different proportions of UDP in the diet. The behaviour of the alpacas in the 100% and 0% UDP protein groups was also monitored.