Botanical and chemical composition of diets selected by alpacas (Lama pacos) pastured in the Ulla Ulla wetlands

Citation data:

Brigham Young University - Provo

Publication Year:
2004
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Downloads 51
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Repository URL:
https://scholarsarchive.byu.edu/etd/5382; https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=6381&context=etd
Author(s):
López López, Lino Constancio
Publisher(s):
Brigham Young University - Provo
Tags:
Alpaca--Nutrition--Bolivia; Animal Sciences; Life Sciences; Nutrition
thesis / dissertation description
This study was done in the subtropical high Andes of Ulla Ulla. Its objectives were to determine the botanical composition, nutritional value, and preferred forages in the wetlands (hydromorphic and mesico) diet, by season (dry and wet), and by botanical family (12 families). Three-hundred sixty samples were collected from 6 alpacas with esophageal fistulations, and from them nutritional value and botanical composition were determined; the latter was compared with the botanical composition of the wetlands to determine preference. The results are highly significant (p<0.01) for botanical families, interaction between season and family, interaction of wetland type and family, and interaction of the season with wetland type and family. Species from the family Juncaceae were the most consumed with 27.78%, followed by moderate consumption of Cyperaceae (21.03%), Gramineae (15.02%), and Rosaceae (12.39%). Lower consumption occurred with Umbeliferaceae and Asteraceae with 6.61% and 5.64%, respectively, and the lowest consumption was of Plantaginaceae, Scrophulariaceae, minor plants, Gentianiaceae, unidentified plants, and Ranunculaceae with 2.86%, 2.50%, 2.17%, 2.08%, 1.03%, and 0.89%, respectively. The botanical families with the greatest preference value (PV) were Gramineae (PV=6.48), Scrophulariaceae (PV=8.75), Gentianiaceae (PV=7.55), and Ranunculaceae (PV=8.16). Proportional preference was observed in Juncaceae (PV=1.49), Cyperaceae (PV= -1.72), Rosaceae (PV=1.82), and Umbeliferaceae (PV= -0.82). The Asteraceae family was classified as a forced preference (PV= -6.29). The average nutritional value of the diet shows high values: 14.69% of raw protein, 14.58% ash, 85.42% organic matter, 21.43% raw fiber, and 31.00% neutral detergent fiber. It was concluded that alpacas efficiently select their diet for nutritional value, however, consumption is not appropriate, which results in negative live weight gain, especially in the dry season. On the other hand, the plants' preference values correspond to the lowest and one of the highest is a forced preference, according to the botanical composition of the wetland, which suggests that the preferred plants are repeatedly consumed in current continual pastures, and that alpacas are forced to consume unpalatable plants. This reflects on bad CANAPAS wetlands management in Ulla Ulla. Consequently, reversing this situation implies changes in pasture management and a reduction of the animal load.