Research Article Prevalence of Dog Erythrocyte Antigen 1 in 7,414 Dogs in Italy Anyela Andrea Medina Valentin, Alessandra Gavazza, and George Lubas Veterinary Transfusional Center (CTV), Department of Veterinary Sciences, University of Pisa, Via Livornese Lato Monte, San Piero a Grado, 56122 Pisa, Italy Correspondence should be addressed to Anyela Andrea Medina Valentin; anyela.medina@vet.unipi.it Received 11 May 2017; Revised 30 June 2017; Accepted 1 August 2017; Published 24 September 2017 Academic Editor: Ingo Nolte Copyright © 2017 Anyela Andrea Medina Valentin et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Te study aim was to establish the prevalence of DEA 1, the most immunogenic and clinically important blood group in canine blood transfusion, in 7,414 dogs from Italy. Te potential sensitization risk following a frst transfusion and the acute reaction risk following a second transfusion given without a cross-matching and blood typing test were also calculated. Dogs tested were purebred (4,798) and mongrel (2,616); 38.8% were DEA 1 negative and 61.2% were DEA 1 positive. High prevalence for DEA 1 positive blood type was found in Ariegeois and English Setter, whereas German Shepherd and Boxer had higher DEA 1 negative blood type. Breeds with blood type never reported before included French Brittany Spaniel and Pug showing a high prevalence of DEA 1 positive type, while French Bulldog and West Highland White Terrier were more ofen DEA 1 negative. Just 48.8% of purebred and 13.9% of mongrel dogs were considered as prospective blood donors based upon their blood type. Most of the breeds had a sensitization risk of 20.0–25.0%. Rottweiler and Ariegeois had less risk of sensitization (9.4 and 4.2%) and the minor risk of an acute transfusional reaction (0.9–0.2%). Te prevalence of DEA 1 positive and negative dogs in Italy agrees with most of the data already reported in the literature. 1. Introduction Canine blood groups are recognized and have standardized terminology as Dog Erythrocyte Antigen (DEA). Te DEA system includes seven well-known blood groups (DEA 1, 3, 4, 5, 6, 7, and 8) with over twenty antigen specifcities [1–4]. Other nonstandardized antigens within DEA such as Dal [3, 5] and the recently described Kai 1 and 2 have been reported [6]. Canine blood groups comprise a two-allele system with a positive and negative type. Te DEA 1 blood group system initially was described with 3 types, DEA 1.1, 1.2, and likely 1.3 [3, 7, 8]. Utiliz- ing quantitative fow cytometry and an immunochromato- graphic technique with a monoclonal anti-DEA 1 alloanti- body the continuum of DEA 1 negative to weakly (1+) up to strongly DEA 1 positive (4+) blood type was observed in contrast to the originally described DEA 1 system and with a signifcant correlation between these tests [9]. Recently, an autosomal dominant mode of inheritance of 4 alleles of DEA 1 with strong (4+) to weak (1+) reactivity was discovered. DEA 1 positive alleles are dominant over DEA 1 negative allele without any direct correlation with the historical DEA 1.2 positive subtype [10]. So now, it is accepted to speak about the DEA 1 group as a whole without any subtype [9, 10]. Natural occurring antibodies against DEA 1 antigen in dog’s erythrocytes have never been positively identifed [11]. On the other hand, natural antibodies against DEA 3, 5, and 7 have been documented with a prevalence of 6%, 23%, and 45%, respectively [2]. However, although all canine blood group antigens can stimulate the formation of alloantibodies, DEA 1 seems to be the most immunogenic and also is considered the most clinically important. Alloantibodies will appear following the frst transfusion in DEA 1 negative recipient dogs receiving positive DEA 1 red blood cells (RBCs) within 4–14 days [11–14]. Sensitization of the recipient and production of alloantibodies can result in a severe acute hemolytic transfusion reaction and even death if a second DEA 1 positive RBC transfusion is administered to the same patient [15–17]. Te risk of alloantibody production and transfusion reactions against antigens other than DEA 1 is Hindawi Veterinary Medicine International Volume 2017, Article ID 5914629, 10 pages https://doi.org/10.1155/2017/5914629