Bovine Blood Xenotransfusion as a Therapeutic Approach for the Treatment of Acute Blood Loss in Sheep.

Hemotherapy in small ruminants is indicated for several acute and chronic conditions; however, its clinical use is often limited by the difficulty in identifying suitable donors, particularly regarding blood volume availability and hematologic compatibility. Xenotransfusion in small ruminants with bovine blood may represent a practical alternative in emergency situations involving severe anemia when homologous donors are unavailable. This study evaluated the clinical, hematologic, biochemical, and blood gas responses of sheep subjected to acute blood loss followed by bovine whole blood xenotransfusion. Six healthy adult castrated male sheep (mean body weight 44.3 ± 7.2 kg) underwent removal of 40% of their estimated total blood volume. Parameters were assessed before hemorrhage induction (T0) and at times T30, T6h, T12h, T24h, T48h, T72h, T96h, T5d, T6d, T7d, T8d and T16d after transfusion. Acute blood loss significantly reduced packed cell volume and erythrocyte count at T0 (p < 0.05). After xenotransfusion, packed cell volume increased at T30min, T6h, and T12h and remained stable until T72h (p < 0.05), with progressive erythrocyte recovery and sustained macrocytosis. Total leukocyte count remained unchanged, whereas platelets increased at T7D (p < 0.05). Total protein decreased at T0 and subsequently increased. Transient elevations in urea, creatinine, glucose, pO2, and SO2 were observed (p < 0.05), without acid-base imbalance. Clinical parameters progressively stabilized, and no severe transfusion reactions occurred. Bovine whole blood xenotransfusion may represent a promising therapeutic alternative for sheep subjected to acute blood loss under the experimental conditions evaluated in this study. The procedure was associated with improvements in clinical, hematological, and biochemical parameters, and no severe transfusion reactions were observed during the monitoring period. These findings support the potential clinical applicability of this approach as an emergency intervention in situations where homologous donors are not readily available.