Nutritional diseases of South American camelids

Literature describing nutritional or nutrition-related diseases of llamas and alpacas was reviewed. Case reports of copper toxicity, polioencephalomalacia, plant poisonings and urolithiasis accounted for the greatest number of literature citations relative to llamas and alpaca nutritional diseases. However, the overall number of published studies detailing nutritional disease of llamas and alpacas is very limited. Metabolic bone disease, associated with Vitamin D deficiency, and hepatic lipidosis were metabolic diseases for which controlled research studies were completed to address underlying mechanisms. Circumstantial evidence would suggest llamas and alpacas are similar to other ruminants relative to most nutrient deficiency or toxicity disease problems. Llamas and alpacas are unique compared to other ruminant animals in their susceptibility to zinc and Vitamin D deficiency diseases. A zinc-responsive dermatosis has been described, but the true role of zinc deficiency is debated. Llamas and alpacas show a seasonal deficiency in Vitamin D resulting in a hypophosphatemic rickets syndrome. Camelids may have a lower capacity to endogenously synthesize Vitamin D or higher requirement compared to other species. Although mechanisms are not fully understood, llamas and alpacas are somewhat different in metabolic responses to negative energy balance and subsequent hepatic lipidosis. Further research is necessary to better define llama and alpaca nutrient requirements and metabolism as they directly impact potential for nutritional disease. © 2005 Elsevier B.V. All rights reserved.