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Supplemental material, sj-pdf-2-vet-10.1177_03009858221117859 for Pulmonary bleeding in racehorses: A gross, histologic, and ultrastructural comparison of exercise-induced pulmonary hemorrhage and exercise-associated fatal pulmonary hemorrhage by Guido Rocchigiani, Ranieri Verin, Francisco A. Uzal, Ellen R. Singer, Paola Pregel, Lorenzo Ressel and Emanuele Ricci in Veterinary Pathology

International audience; Contaminated poultry and eggs are major sources of Salmonella infections in humans. The decrease of Salmonella foodborne infections is dependent on the reduction of Salmonella burden at primary production stages. Defensins are major antimicrobial peptides, effectors of innate immunity playing a key role in the protection of mucosal surfaces of animals and humans through multiple modes of action such as bacterial membrane disruption, chemotactic properties towards leucocytes, and tissue repair [1](Lay and Gallo, 2009). Enteric defensins are also regulators of intestinal microbial ecology [2](Salzamn et al., 2010). The sustained production of defensins in the gut could constitute a valuable mean of control in gut health.Aim of the work was to investigate if the infection of one-day-old chickens with S. Enteritidis deleted of ZnuABC transporter (S. Enteritidis ΔznuABC) used as a vaccine candidate modifies the course of avian β-defensin genes expression during the first 4 weeks of chicken life.Microbiological and histopathological investigations were carried out in order to assess the pathogen colonization of the organs and the effects of vaccination in the intestine.Forty white Leghorn hens were divided into two groups of 20 animals (treated and control group, respectively). One mL of sodium bicarbonate buffer containing105 CFU ofS. Enteritidis ΔznuABC was administered by oral gavage to each animal of the treated group; animals of the control group received 1 mL of sterile sodium bicarbonate buffer. Five animals in each group were sacrificed on day 3, 7, 17, 32 and 86 post-administration. Liver, caecal tonsils and portions of intestine (colon) were aseptically removed and processed for bacteriological, biomolecular and histological analyses.The results of the microbiological analyses showed a decrease in the concentration of Salmonella in the intestine in the first 32 days and a complete disappearance in about 3 months. This result highlights the attenuation of the vaccine strain in the chicken and its possible use in animals with long production cycles, in accordance with the data reported in the literature on attenuated strains of S. Typhimurium [3](Van Immerseel et al., 2005)). The biomolecular analysis showed a pattern already found in several studies for the AvBD1, AvBD2, AvBD4 and AvBD7 genes, not significantly modified by vaccination. In contrast, AvBD9, AvB10 and AvBD14 showed a new pattern of expression in the control group, not observed in treated animals, but without significant differences between the two groups. Histological analysis showed an increase in haemorrhages in the colon and caecal tonsils in treated animals and an activation of lymphoid follicles of the colon at day 7, probably caused by intestinal colonization. These results highlight some possible issue of the vaccine (haemorrhages).Epithelial and haemorrhagic damage was also observed in control group, thus requiring further investigations.

Haemoparasites and their effects on hooded crows (Corvus corone cornix) are poorly studied. The aims are to evaluate the prevalence of Haemoproteus spp./Plasmodium spp. or Leucocytozoon spp., to correlate this with gross and histopathological findings, and to investigate the association among infection and geographical origin, age, gender, parasite distribution and prevalence among organs. Hooded crows (n = 47) were collected within a regional culling programme from 3 districts in the province of Turin (Italy) and subjected to necropsy. Histological and molecular analyses were carried out on some tissues. Leucocytozoon spp. was detected in 46 crows (97.9%) by polymerase chain reaction (PCR), whereas 28 birds (59.6%) were found to be positive for Haemoproteus spp./Plasmodium spp. The distribution of parasites in several organs varied significantly, showing that Leucocytozoon spp. is ubiquitous in organs in contrast with Haemoproteus spp./Plasmodium spp., which have a specific predilection for spleen and lungs. The prevalence of Haemoproteus spp./Plasmodium spp. also differed significantly among the crows captured in the areas of the study. The high prevalence of haemoparasites emphasizes the success of ornithophilic vectors and the susceptibility of this species to infection. Differences in prevalence among the sites are probably due to orographic features of the areas, variations in vector species and density, or to crow population size or structure. In spite of the high infection rate, no gross and histological lesions were found. This finding further suggests an evolutionary adaptation between crows and avian blood parasites.