Tesis de grado, Universidad Mayor de San Andres, Facultad de Agronomia, Carrera de Ingenieria Agronomica. / Abstract in Spanish and English.

In 132 rabbits belonging to the Cunicola La Esperanza Farm of the city of El Alto in the department of La Paz, the principle physical characteristics of the angora rabbit fiber were determined in a period of 3 shearings. As such they were organized into 2 groups, clearly differentiated by their sex (female and male). The obtained fiber of the different shearings were weighed in order to determine the performance of each animal and subsequently analyzed the wool in the Experimental Station of Patacamaya, where they determined the diameter, length of hair and marrow composition. The results were subjected to a statistical analysis with the help of the SAS program. The effects of the principle studied factors (sex, age, number of shearing) showed highly significant differences (p<0.01). The fiber yields for males and females were 70.76 and 81.72 g respectively; as such the fiber yields of 57.77, 82.91, 84.28, 80.01, 71.36, 81.11 and 76.25 g for those under the age of 1 year, 1 year, 2 years, 3 years and first shearing, second shearing, third shearings respectively. The age of the animals and the number of shearings were the principle causes of the variation of the performance of the fiber. The male rabbits obtained 13.10 microns in diameter, 56.10% of marrow composition and 4.10 cm of length, and the female rabbits 13.91 microns of diameter, 65.34% of marrow composition y 4.23 cm of length, being the effect of the sex most highly significant (p<0.01). The fineness of fiber of the animals was 12.80, 13.07, 14.28 y 13.88 microns respectively for the ages younger than 1 year, 1 year, 2 years and 3 years, a marrow composition of 57.68, 60.54, 60.56 y 64.10%, for the same ages, observing among themselves highly significant differences (p<0.01); except in the variability of the length of the hair. In animals subjected to different numbers of shearing they obtained 13.48, 13.37 and 13.67 microns for the first, second and third shearings respectively and a bone composition of 59.28, 62.32 y 60.56%, observing minimum numerical differences, but not statistical, as in the length of hair.