• Productivity and Nutritive Value of Barley Green Fodder Yield in Hydroponic System

    Barley grain was sprouted in a still hydroponic growing chamber for 6, 7 and 8 day periods and sampled for chemical analyses, protein fractions,in vitro digestion and metabolisable energy (ME) determination. Productivity measured on the basis of the input-output balance of barley grain and GF yield. Results showed that CP, Ash, EE, NDF, ADF and water soluble carbohydrate (WSC) were increased whereas OM and non fiber carbohydrate (NFC) decreased (p < 0.05) in the GF when compared with the original grain. As the growing period extended from day 6 to day 8, the CP, Ash, EE, NDF and ADF were increased but NFC and WSC reduced (p < 0.05). The non protein nitrogen was increased but true protein decreased (p < 0.05) in GF in comparison to barley grain, however no differences was shown among the growing periods for protein fractions. The potential (b) and rate (c) of in vitro gas production shown a decreasing trend (p < 0.05) by sprouting the barley grain up to 8 days. The amount of OM and ME of GF, obtained per kg of cultivated barley grain, were lower than those of the original grain. more »
  • Comparative Productivity and Grazing Behaviour of Huacaya Alpacas and Peppin Merino Sheep Grazed on Annual Pastures

    Adult Huacaya alpaca (mixed sex, mean±S.D., age 5.2±2.7 years, live weight 72.0±9.5 kg) were grazed with Peppin Merino sheep (castrated male, age 3±0.1 years, live weight 54.0±3.9 kg) for 2 years on improved annual pasture at commercial grazing pressures (10–17 dry sheep equivalents/ha) near Melbourne, Australia. Alpacas and sheep gained weight during the first year and then lost weight (proportional loss: alpacas 22%, sheep 20%, NS) before commencing weight gain. Twice the alpacas gained when the sheep lost weight (P more »
  • The Guts of Alpaca Nutrition: Understanding Energy and Protein Metabolism

    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 undegradable 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. The alpacas fed the 0% UDP diet produced fibre of finer diameter than the alpacas fed diets containing higher levels of UDP, but the 0% UDP group spent more time urinating. This suggests that when fed RDP, which should increase the ammonia concentration in the fermentative organs, the excess ammonia is converted to urea in the liver and excreted in urine. Thus the proportion of dietary protein as RDP may influence the pathways of nitrogen metabolism in alpacas. In light of the results from Chapter 3, the experiment in Chapter 5 aimed to determine if protein degradability influenced nitrogen retention or energy balance and whether alpacas utilise nitrogen more efficiently than sheep. It was hypothesised that alpacas fed a diet containing RDP in the form of canola meal would excrete more nitrogen than those fed UDP and, that alpacas fed the same diet as sheep at maintenance would retain more nitrogen. Alpacas and sheep were fed the same diets as used in the experiment for Chapter 3 while they were housed in metabolism pens. Nitrogen and energy balances were measured to determine whether alpacas metabolised nitrogen more efficiently than sheep and whether protein degradability influenced the ability of alpacas to retain nitrogen. The degradability of the protein in the diet did not influence the amount of nitrogen retained in either species and both the sheep and the alpacas retained similar amounts of nitrogen. However, the alpacas tended to retain less nitrogen as a percentage of the nitrogen absorbed from their food than did sheep fed the same diet. The results suggested that sheep and alpacas probably obtain their energy from different components of their food and utilise protein in different ways. In Chapter 6, the ability of alpacas to spare amino acids for fibre growth by utilising a gluconeogenic precursor was determined. It was hypothesised that alpacas supplemented with calcium propionate would produce more fine fibre than un-supplemented animals. Although the diets supplemented with calcium propionate should have provided more energy, the ME intake of all animals was similar. It appears that rather than sparing amino acids, the alpacas regulated their energy intake by refusing to consume additional energy as calcium propionate. Whether alpacas do moderate their energy intake and prefer to utilise protein as their source of glucose for maintenance was examined in Chapter 7. It was hypothesised that irrespective of their energy intake, alpacas would progressively retain more nitrogen as their intake of dietary protein increased. Conversely, it was expected that sheep would retain less nitrogen than alpacas when their intake of dietary protein increased because they rely on gluconeogenic precursors such as propionate, rather than protein, to meet their energy requirement. The alpacas responded to the dietary treatments in a similar manner to sheep by retaining a similar proportion of the dietary nitrogen that they absorbed. However, there was a trend for the alpacas to retain more of the absorbed nitrogen than the sheep when fed a diet that provided almost twice their maintenance requirement of protein. There was some evidence to suggest that alpacas do not regulate their protein intake as they appear to do with their energy intake. The results from these studies have shown that alpacas obtain glucose for energy predominantly from the protein component of their diet as part of an adaptation to the harsh conditions of their native environment. Our understanding of the ability of alpacas to metabolise energy and nitrogen, compared to sheep, will enable producers to be informed of appropriate ways in which to feed their animals to promote productive and reproductive efficiency. more »
  • The DIY (Do It Yourself) Alpaca Feeding System

    The DIY (do it yourself) alpaca feeding program includes: - Regular body scoring, two to four times a year - Weaning most males off of pelleted supplements (including crumbles) - Use of simple, pre-formulated one- to-three ingredient protein/energy supplements - Substitution of locally purchased mineral mix for pricier specialty mixes - Daily and preventive use of probiotics to keep animals healthy and reduce vet bills more »