Publications
Wagener, M. G., et al. (2025). Influence of age on biochemical serum parameters in female alpacas - A retrospective study. Heliyon 11(1): e41097. DOI: 10.1016/j.heliyon.2024.e41097
The determination of biochemical parameters plays an important role in the veterinary care of alpacas, as it can provide an overview of the integrity and function of various organs and metabolic states. Various reference intervals are available for interpreting biochemical results in alpacas, but physiological variations due to age, sex or season should also be considered. Particularly, information on the influence of age is scarce. In a retrospective study, we examined 17 measured and three calculated biochemical parameters of 21 healthy female alpacas from a research herd over a period of nine years. We found significant positive correlations between age and serum triglycerides, selenium, vitamin E, urea, urea/creatinine ratio, calcium/phosphate ratio and significant negative correlations between age and aspartate aminotransferase activity, calcium and phosphate. However, our results differ to some extent from those found in the literature comparing changes in biochemical parameters between juvenile and adult alpacas. Overall, our data suggest that some biochemical parameters in adult alpacas are subject to physiological changes with age, which should be considered when interpreting laboratory results in this species.
Wagener, M. G., et al. (2024). Hematologic parameters in female alpacas during age progression: a retrospective study. Sci Rep 14(1): 492. DOI: 10.1038/s41598-023-50572-9
Alpacas, like all camelids, have elliptical red blood cells (RBCs) in contrast to other mammals. This particular shape is important for increased osmotic resistance and stability. Age-related changes in the RBC count are known in other species, with alterations in both red and white blood cells being described. In alpacas, there are few data on age-related changes, and only a comparison of crias with adult animals. We characterized age-related hematologic changes in a study of 21 female alpacas from a research herd. A total of 87 records of clinically healthy alpacas of different ages were statistically analyzed retrospectively from the hematologic records over a nine-year period. Significant positive correlations of age with hemoglobin (Hb), HCT, MCV, MCH, neutrophils, platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR) were found as well as significant negative correlations of age with lymphocytes in addition to lymphocyte-to-monocyte ratio (LMR). A paired comparison of eight older animals in the herd at three different ages also showed significant differences in the parameters Hb, HCT, MCV, MCH, MCHC, lymphocytes, eosinophils and neutrophils. Similar changes in hematologic parameters have been reported in other species and should be taken into account when interpreting hematologic results in alpacas.