**Background:** Anaemia is common in alpacas, with severe cases (PCV < 0.15 l/l) often attributed to blood loss from Haemonchus contortus infection. Gastric ulcers are also frequent in South American camelids (SACs), but current literature states they rarely cause anaemia. This case challenges that assumption by documenting severe anaemia secondary to a perforated gastric ulcer.
**Methods:** A nine-year-old, 66-kg male alpaca from a herd of ~30 was presented to the Clinic for Swine and Small Ruminants, University of Veterinary Medicine Hannover, with suspected forestomach acidosis after possibly ingesting too many pears. The owners noted pale mucous membranes, hypothermia, and colic. Pretreatment by a local veterinarian included metamizole, butylscopolamine, dexamethasone, IV fluids, and a 500-ml whole blood transfusion. On presentation, the alpaca was recumbent, with rectal temperature 35.7°C, respiratory rate 56 breaths/min, heart rate 140 beats/min, and pale conjunctivae (FAMACHA score 2). Despite emergency treatment (dexamethasone, metamizole, butylscopolamine, doxapram), the animal died within two hours. Laboratory analysis of venous blood revealed severe anaemia (PCV 0.13 l/l, haemoglobin 62 g/l), leucopenia (WBC 5.6 G/l) with band neutrophils (1.26 G/l), azotaemia (creatinine 422 µmol/l, urea 42.6 mmol/l), hypocalcaemia (1.78 mmol/l), hyperphosphataemia (4.81 mmol/l), and elevated CK (805 U/l). No haemotrophic mycoplasmas were detected on blood smear. Faecal examination five days prior showed no gastrointestinal nematode eggs, coccidia, or lungworm larvae. Necropsy revealed a 7-cm focal ulcer in the first compartment with a 2-mm perforation, purulent peritonitis, and multifocal smaller ulcers/erosions in the third compartment. Intestinal contents contained digested blood.
**Key Results:** The cause of death was cardiovascular failure due to ulcerative perforated inflammation of the first compartment with peritonitis. The severe anaemia (PCV 0.13 l/l) was attributed to intraluminal blood loss from the perforated ulcer, as other causes (haemonchosis, mycoplasma, nutritional deficiencies) were excluded. The anaemia was likely regenerative based on the presence of Cabot rings and nucleated red blood cells (2%), though reticulocyte count was not performed. The leucopenia with band neutrophils is consistent with previous reports of gastric ulcers in SACs.
**Clinical Implications:** This case demonstrates that gastric ulcers can cause severe, even fatal, anaemia in alpacas, contrary to prior assumptions. Clinicians should include perforated gastric ulcer in the differential diagnosis for anaemic alpacas, especially when colic and pale mucous membranes are present. Diagnosis is challenging due to nonspecific symptoms, and occult blood tests may not detect all bleeding ulcers. Prophylactic measures include stress reduction and cautious NSAID use. Blood transfusion may be temporarily beneficial but may not resolve ongoing blood loss from a perforated ulcer.