- Twelve adult male alpacas were given either 0·67 (low) or 2·0 (high) × assumed maintenance requirements for a period of 6 weeks after which time each was transferred to the alternative level of nutrition for a further 6 weeks. Fibre samples were taken from two 10-cm2 areas on the mid-side position of each animal at 2, 6, 8 and 12 weeks, and measurements of fibre weight, yield (clean fibre weight/raw fibre weight), fibre diameter and fibre length made on the samples collected at weeks 6 and 12. The higher level of feeding resulted in higher clean fibre weight (low = 0·42 (s.e. 0·03); high = 0·53 (s.e. 0·04)mg/cm2 per day, P < 0·001) and fibre growth rate (low = 186 (s.e. 10); high = 223 (s.e. 14) yon/day, P < 0·05). Changes in yield (low = 0·917 (s.e. 0·006); high = 0·929 (s.e. 0·009)) and mean fibre diameter (low = 31·4 (s.e. 1·9); high = 32·1 (s.e. 1.6) \xm) were not statistically significant. Calculations showed that the increased weight of fibre attributed to the higher level of nutrition could be explained in terms of the observed increases in fibre-length and diameter but that, unlike the sheep in which the ratio fibre length: diameter remains relatively constant under varying nutritional regimes, the effect of nutrition in the alpaca has a proportionally larger effect on fibre length than on fibre diameter. more »
- The origins of South America's domestic alpaca and llama remain controversial due to hybridization, near extirpation during the Spanish conquest and difficulties in archaeological interpretation. Traditionally, the ancestry of both forms is attributed to the guanaco, while the vicuña is assumed never to have been domesticated. Recent research has, however, linked the alpaca to the vicuña, dating domestication to 6000–7000 years before present in the Peruvian Andes. Here, we examine in detail the genetic relationships between the South American camelids in order to determine the origins of the domestic forms, using mitochondrial (mt) and microsatellite DNA. MtDNA analysis places 80% of llama and alpaca sequences in the guanaco lineage, with those possessing vicuña mtDNA being nearly all alpaca or alpaca–vicuña hybrids. We also examined four microsatellites in wild known–provenance vicuña and guanaco, including two loci with non–overlapping allele size ranges in the wild species. In contrast to the mtDNA, these markers show high genetic similarity between alpaca and vicuña, and between llama and guanaco, although bidirectional hybridization is also revealed. Finally, combined marker analysis on a subset of samples confirms the microsatellite interpretation and suggests that the alpaca is descended from the vicuña, and should be reclassified as Vicugna pacos. This result has major implications for the future management of wild and domestic camelids in South America. more »
- Our objectives were to measure alpaca (Lama pacos) diet quality and botanical composition seasonally on 2 high elevation range-sites (bofedal and Altiplano) in the Andes Mountains of Peru. The bofedal site was a perennially green sedge and forb community located at 5,000 m elevation. The Altiplano site, located at 3,190 m, was predominately bunchgrass. We collected diets from free-ranging, esophageally fistulated alpacas at each site. Alpaca diets at both sites were highest in grasses during the wet and early dry season. As the dry season progressed, bofedal alpaca diets were comprised largely of sedges and reeds (78%) while Altiplano diets remained predominantly grasses (68%). Forb consumption varied annually between 8 and 29% of the diet on both sites. Crude protein (CP) in bofedal diets (12.3%) averaged higher than on the Altiplano (10.2%). Values were lowest during August (6.1%) on the Altiplano and in July (8.0%) on the bofedal. In vitro organic matter digestibility (IVOMD) of alpaca diets on the bofedal (63%) was similar to the Altiplano site (64%) when averaged for all seasons. IVOMD was lowest during August (49%) at the Altiplano site and in October (50%) on the bofedal. Low dietary CP and IVOMD during the late dry season (Aug.-Oct.) denote this period as nutritionally critical for both sites. more »
- Two hundred eighty adult female alpacas (Lama pacos) and 200 tui alpacas (young alpacas 3-7 months of age) were grazed on a Festuca-Calamagrostis association at the South American Camelids Research Station, La Raya, Peru, during the dry season and early wet season of 1981 (June-December). Vegetation was sampled monthly during this period for herbage yield by species. Fecal material from both adult female alpaca and tui alpaca was collected monthly for microhistological analyses of food habits. Alpacas were primarily grazers rather than forb eaters during the dry season and early wet period of 1981. Forage classes consumed were different for adult and tui alpaca. Tui alpaca consumed more grass-like plants and forbs than adults during the driest months. Diet indices revealed the following as highly selected, common forage species: Eleocharis albibracteata, Poa. sp., Calamagrostis heterophylla, C. vicunarum, Alchemilla pinnata, Muhlenbergia fastigiata, and Carex spp. Highly selected, trace species were P. gymnantha, M. peruviana, Stipa brachiphylla, Ranunculus limoselloides, and Trifolium amabile. Festuca dolichophylla had been considered by range managers as highly preferred species overall. However, because it was the most abundant species (73% of the total forage yield), F. dolichophylla had a low selection index during the dry season. Alpacas consumed remarkable quantities of grass seeds (up to 20% of the diet) during the driest months of the year, apparently compensating for low quality forage. more »
- From spring 1990 to autumn 1993, 44 spring-mated and 82 autumn-mated alpacas at Flock House Agricultural Centre (FH) had their pregnancies monitored by ultrasound every 10–14 days from day 20 to day 120 of gestation. A further 32 autumn-mated alpacas at Tara Hills High Country Research Station (TH) were monitored in 1992. Trans-rectal probes were used in early gestation and trans-abdominal probes in late gestation. As techniques for pregnancy diagnosis in alpacas improved during the experiment, the stage of gestation at which pregnancies were first confirmed became earlier. From spring 1991 onwards most pregnancies were first diagnosed at 20–30 days of gestation. Progesterone concentrations were determined from individual blood samples collected each time alpacas were brought in for pregnancy diagnosis from spring 1991 onwards. Foetal loss from day 30 onwards was 25.7% with the foetal losses after day 120 of gestation being 9.6–16.7% in different mating groups. There were apparent differences in the pattern of foetal loss between autumn- and spring-mated alpacas at FH with foetal losses before day 81 being 17.3% and 2.8% respectively and no significant difference in foetal loss after day 81 of gestation. The younger New Zealand born alpacas had a similar incidence of foetal loss to the older Chilean born alpacas. There was a suggestion at TH that the stress of transport and relocation of a group of alpacas at 212 ± 3 days of gestation precipitated a high incidence of foetal loss. The spring-mated alpacas had a longer gestation length (350.1 ± 2.7 days) than autumn-mated alpacas at FH (340.2 ± 1.9 days). more »