< back to Mammal list          > Reference list

THE DIGESTIVE SYSTEM OF VERTEBRATES

MAMMALS: Llama

Llama (Llama glama) digestive tract (Stevens & Hume 1995)



Figure 4.9.  Llama expanded forestomach.  E designates esophageal entrance, and P designates pylorus.  (Modified from Stevens and Hume 1995.)  (CD Figure 5.9)



Figure 5.8. Schematic representation of the llama stomach. The esophagus (1) enters the first compartment (A), which is partially divided into cranial (3) and caudal (4) sacs by a pillar of muscle (7), and separated from the second compartment (B) by a constriction (8). Both compartments include regions of saccules (5,6,9) containing cardiac glandular mucosa. A ventricular groove (2) runs along the lesser curvature of the forestomach between the esophagus and the third compartment (C). The initial four-fifths of the third compartment is also lined with cardiac glandular mucosa (11,12). The terminal segment (13) is lined with proper gastric mucosa and separated from a duodenal ampulla (D), by a pyloric sphincter (14). (From Vallenas, Cummings, and Munnel 1971.)  (CD Figure 6.8)



Figure 5.9.  Left, lateral, longitudinal section of the llama stomach showing the entrance of the esophagus (A), transverse pillar (B) between the cranial and caudal sacs of the first compartment and entrance to the second compartment (C). It also shows the openings to the glandular saccules in the first compartment.  (Modified from Vallenas, Cummings, and Munnel 1971.)  (CD Figure 6.9)



Figure 5.10.  Pressure recording of cyclic contractions of llama forestomach. (From Vallenas and Stevens 1971a.)  (CD Figure 6.10)



Figure 5.11.  Cyclic contraction of the first compartment of the llama  forestomach. A-D  show contractions of pillar and sacs. Cyclic eversion of caudal sac pouches during the three stages of contraction is shown in drawings on the right. (From Vallenas and Stevens 1971a.)  (CD Figure 6.11)


Table 6.6.  Mean retention time for herbivorous forestomach fermenters (CD Table 7.6)

Although digesta retention times are affected by differences in the diet, and in the body temperatures of the bird, sloth and other eutherian mammals, foregut fermenters retain particulate digesta as long or longer than fluid digesta. Most small forestomach fermenters retain fluid and particles for equal lengths of time, but particles are selectively retained by the forestomach of large species and this tends  to increase with an increase in dietary fiber. (modified from Stevens and Hume 1995)