Two striped dolphins (SD1, SD2), stranded along the Ligurian coast of Italy, were diagnosed with a nonsuppurative meningoencephalitis associated with previously undescribed protozoan tissue cysts. As tissue cysts were morphologically different from those of Toxoplasma gondii, additional histopathological, immunohistochemical, ultrastructural, and biomolecular investigations were performed, aiming to fully characterize the organism. Histopathology revealed the presence of large Sarcocystis-like tissue cysts, associated with limited inflammatory lesions in all CNS areas studied. IHC was inconclusive, as positive staining with polyclonal antisera did not preclude cross-reaction with other Sarcocystidae coccidia. Applied to each animal, 11 different PCR protocols precluded a neural infection by Sarcocystis neurona, Sarcocystis falcatula, Hammondia hammondi, and Neospora caninum. T. gondii coinfection was confirmed only in dolphin SD2. Sarcocystis sp. sequences, showing the highest homology to species infecting the Bovidae family, were amplified from SD1 myocardium and SD2 skeletal muscle. The present study represents the first report of Sarcocystis-like tissue cysts in the brain of stranded cetaceans along with the first description of Sarcocystis sp. infection in muscle tissue of dolphins from the Mediterranean basin.

In the setting of the recent COVID-19 pandemic, transmission of SARS-CoV-2 to animals has been reported in both domestic and wild animals and is a matter of concern. Given the genetic and functional similarities to humans, non-human primates merit particular attention. In the case of lemurs, generally considered endangered, they are believed to be susceptible to SARS-CoV-2 infection. We have conducted a study for evidence of SARS-CoV-2 infection among the 43 lemurs of Mundomar, a zoological park in Benidorm, Spain. They belong to two endangered lemur species, 23 black-and-white ruffed lemurs (Varecia variegata) and 20 ring-tailed lemurs (Lemur catta). Health assessments conducted in 2022 and 2023 included molecular analyses for SARS-CoV-2 RNA of oral and rectal swabs using two different RT-qPCR assays, always with negative results for SARS-CoV-2 in all animals. The assessment also included serological testing for antibodies against the receptor-binding domain (RBD) of the spike protein (S) of SARS-CoV-2, which again yielded negative results in all animals except one black-and-white ruffed lemur, supporting prior infection of that animal with SARS-CoV-2. Our data, while not indicating a high susceptibility of lemurs to SARS-CoV-2 infection, show that they can be infected, adding to the existing information body on potential ways for SARS-CoV-2 virus spreading in zoos, highlighting the need for animal surveillance for the virus.

Lactococci have been associated with fetal and neonatal infections in humans and cattle. Here we describe a case of reproductive loss attributed to Lactococcus petauri in a lemur. A full-term black-and-white ruffed lemur ( Varecia variegata ) was found dead in the indoor area of a zoologic exhibit. Classification as a late-term abortion or stillbirth was unclear as the precise gestational time was unknown. A medical checkup of the dam revealed fever and neutrophilic leukocytosis; recovery followed treatment with enrofloxacin. The main histologic findings were placental edema and hemorrhage, hepatic necrosis, desquamated amniotic epithelial cells in alveoli, and subendocardial and myocardial hemorrhages. Tissue Gram stain revealed abundant gram-positive cocci arranged in short chains in the placenta and liver. Toxoplasma gondii was not detected by immunohistochemistry. Bacterial isolates from the placenta and fetal liver were identified as Lactococcus garvieae by MALDI-TOF MS. However, the isolates were found to be L. petauri by determining their in-silico DNA–DNA hybridization and average nucleotide identity values using pairwise comparisons of their whole-genome sequences and the genomes of the type strains. The antimicrobial susceptibility of isolates by the disk diffusion method revealed resistance to tylosin, gentamicin, apramycin, neomycin, amikacin, ampicillin, and florfenicol. We attributed the reproductive loss in this lemur to placental and fetal infection by L. petauri .