Milk intake studies in llamas (Lama glama) using the “dose-to-the-mother” technique

The knowledge of milk and milk nutrient intakes in suckling young is essential for giving recommendations on adequate nutrient supply. In a study involving 6 lactating llama (Lama glama) dams and their suckling young, milk intake and total water turnover were measured at three different stages of lactation (wk 3–4, 10–11 and 18–19 post partum (PP)) using the “dose-to-the-mother” (DTTM) technique. The method involved the application of the stable hydrogen isotope Deuterium (2H) to the lactating dam. In suckling llamas, total water turnover increased with age (P < 0.01), whereas the milk-water fraction decreased (P < 0.001). With increasing age less water from milk and more water from other sources was ingested. By contrast, the fraction of the milk-water excreted by thedamdid not change, indicating a fairly constant relationship between milk-water excreted via milk and total water ingested during lactation. Milk intake of the young, which also reflected the dams’ milk output, decreased with age (P < 0.001). The results of the present investigation suggest that the “dose-to-the-mother” technique used here gives reasonable estimates of milk intake in suckling llamas and can serve as basis for estimating nutrient requirements. Compared with the isotope dilution technique, the presentDTTMmethod has the advantage that it also allows an estimate of the intake of non-milk-water of the suckling young if certain assumptions are made. Based on the present results, daily maintenance requirements for suckling llamaswere calculated as approximately 310 kJ ME/kg BW0.83. The ME required for the production of measured milk yields were estimated as 16.27, 14.74 and 12.77 MJ/d for the three measurement periods at wk 3–4, 10–11 and 18–19 PP, respectively