Erythrocyte dyscrasia, anemia, and hypothyroidism in chronically underweight llamas.

A syndrome characterized by anemia, erythrocyte dyscrasia, low body weight, and hypothyroidism was observed in 8 llamas (Lama glama). At initial examination (1 to 23 months of age; median, 7.5 months), llamas (3 males, 5 females) were markedly underweight (29 to 55 kg; median, 36 kg) and anemic (PCV, 12.9 to 25.5% [median, 19%]). Five of the llamas became progressively more anemic over time; in 2 of them, PCV decreased to less than 10%. Erythrocyte changes included severe poikilocytosis, anisocytosis, asymmetric distribution of hemoglobin within the cytoplasm, and cytoplasmic extensions from one or both poles. Six llamas had moderate to severe valgus deformities of the carpus. All llamas had low baseline serum thyroxine concentration and diminished response to thyrotropin administration. Baseline and post-thyrotropin triiodothyronine concentrations did not have consistent patterns. Five llamas were hypophosphatemic and 7 had low serum iron concentration (iron concentration was not determined in 1 llama). Orally administered iron supplementation did not induce clinical improvement. Because 3 of the affected llamas were full sisters, a genetic basis for the problem has to be considered. It was not possible to evaluate the familial relationship of the other 5 affected llamas. Although the underlying cause of the problem was not established, the prognosis for affected llamas is guarded to poor.