Background: Autologous blood transfusion in acute blood loss into the abdomen is widely used in small animal and human emergency medicine but is not well described in horses. Objectives: To evaluate the outcomes of autologous transfusion of noncitrated blood in horses with haemabdomen in perioperative and non-perioperative haemorrhage cases. Study design: Retrospective study of clinical records. Methods: Data were extracted from records of nineteen horses diagnosed with haemoabdomen in years 2020–2025, treated with autologous transfusions of noncitrated blood. Six perioperative haemorrhage cases (1 female and 5 males) and thirteen non-perioperative haemorrhage cases of various aetiology (12 females and 1 male) were included in the study. Data on hospitalisation period, amount of transfused blood, number of transfusions, complications, short- and long-term outcomes were compared between the study groups. Results: Nineteen horses aged 3–28 (median age 14) were diagnosed with haemabdomen based on transabdominal ultrasonography and abdominocentesis. Clinical findings on initial examination included abdominal discomfort, tachycardia, prolonged capillary refill time and pale mucous membranes. All nineteen horses underwent autotransfusion of whole noncitrated blood. Total blood volume transfused was 7-38.75 L (median 21.5 L; IQR: 18.5) for the non-perioperative group and 4.5-29.5 L (median 18.25; IQR: 18.5) for the perioperative group. Rapid clinical deterioration was observed in 2 horses in the non-perioperative group and 1 horse in the perioperative group, necessitating euthanasia. The remaining 11 horses in the non-perioperative group (survival rate 11/13) and 5 horses in the perioperative haemorrhage group (survival rate 5/6) survived until discharge following 3–15 days of hospitalisation (median 8.5 days). Main limitations: Retrospective design; heterogeneous, warmblood-oriented population; unbalanced sex distribution in study groups. Conclusions: Autotransfusion of noncitrated blood may be a valuable alternative to standard allogenic blood transfusions and seems to be beneficial for haemoabdomen treatment in all treated haemorrhage cases.

[1]¿p1 [1]¿m1 Background: WNV appears to have rapidly expanded its geographical range in Europe, causing increasing numbers of outbreaks in both humans and horses. In August 2024, WNV was found in dead crows in Warsaw, Poland, following a significant die-off of various bird species. Shortly after that, first cases of WNV in Poland were confirmed in horses and suspected in humans. At present, there is no specific treatment for WN encephalitis and new treatment protocols are urgently required. Objectives: Describing clinical manifestation and treatment outcomes of three confirmed neuroinvasive WNV infections in horses in Poland, treated with immunised plasma and post-exposure vaccination. Study design: Non-comparative study, case series. Methods: Three horses were admitted to a referral hospital in central Poland with moderate to severe neurological symptoms. A novel treatment protocol involving the use of immunised plasma and post-exposure vaccination was developed and treatment outcomes were assessed through clinical examination and measurement of anti-WNV IgM and SAA levels. Results: Autumn 2024 brought the first confirmed WNV cases in horses in Poland. Two out of the three horses admitted to the hospital made a full recovery. A combination of supportive treatment, post-exposure vaccination and transfusion of plasma from a vaccinated donor seems to improve outcomes in horses with neuroinvasive WNV infection. Main limitations: Small study group size due to low incidence of WNV infections in Poland and a number of cases remaining undiagnosed. Only two of the described horses were treated with donor plasma due to timing of the admission of the first patient. Conclusions: Laboratory-confirmed West Nile Virus infections are a new disease in the horse population in Poland and Europe, and veterinarians throughout our continent need to include WNV in their differential diagnosis of neurological disorders and to equip themselves with knowledge and skills to treat such patients.