Prediction of SARS-CoV-2 hosts among Brazilian mammals and new coronavirus transmission chain using evolutionary bioinformatics

Severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2 are thought to transmit to humans via wild mammals, especially bats. However, evidence for direct bat-to-human transmission is lacking. Involvement of intermediate hosts is considered a reason for SARS-CoV-2 transmission to humans and emergence of outbreak. Large biodiversity is found in tropical territories, such as Brazil. On the similar line, this study aimed to predict potential coronavirus hosts among Brazilian wild mammals based on angiotensin-converting enzyme 2 (ACE2) sequences using evolutionary bioinformatics. Cougar, maned wolf, and bush dogs were predicted as potential hosts for coronavirus. These indigenous carnivores are philogenetically closer to the known SARS-CoV/SARS-CoV-2 hosts and presented low ACE2 divergence. A new coronavirus transmission chain was developed in which white-tailed deer, a susceptible SARS-CoV-2 host, have the central position. Cougar play an important role because of its low divergent ACE2 level in deer and humans. The discovery of these potential coronavirus hosts will be useful for epidemiological surveillance and discovery of interventions that can contribute to break the transmission chain.

Differential expression of urinary volatile organic compounds by sex, male reproductive status, and pairing status in the maned wolf (Chrysocyon brachyurus)

The maned wolf (Chrysocyon brachyurus) is an induced ovulator. Though the mechanism of ovulation induction remains unknown, it is suspected to be urinary chemical signals excreted by males. This study assessed volatile organic compounds (VOCs) in weekly urine samples across 5 months from 13 maned wolves (6 intact males, 1 neutered male, 6 females) with the goal of identifying VOCs that are differentially expressed across sex, reproductive status, and pairing status. Solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) were used to extract and separate VOCs that were identified via spectral matching with authentic standards, with spectral libraries, or with new software that further matches molecular fragment structures with mass spectral peaks. Two VOCs were present across all 317 urine samples: 2,5-dimethyl pyrazine and 2-methyl-6-(1-propenyl)-pyrazine. Fifteen VOCs differed significantly (Adj. P < 0.001 and |log2 fold change| >2.0) between intact males and females. Using partial least squares-discriminant analysis, the compounds with the highest importance to the sex classification were delta-decalactone, delta-dodecalactone, and bis(prenyl) sulfide. Sixty-two VOCs differed between intact males and the neutered male. Important classifier compounds were 3-ethyl 2,5-dimethyl pyrazine, 2-methyl-6-(1-propenyl)-pyrazine, and tetrahydro-2-isopentyl-5-propyl furan. Several VOCs established as important here have been implicated in reproductive communication in other mammals. This study is the most robust examination of differential expression in the maned wolf thus far and provides the most comprehensive analysis of maned wolf urinary VOCs to date, increasing the sample size substantially over previous chemical communication studies in this species. New data analysis software allowed for the identification of compounds in the hormone-producing mevalonate pathway which were previously unreported in maned wolf urine. Several putative semiochemicals were identified as good candidates for behavioral bioassays to determine their role in maned wolf reproduction, and specifically in ovulation induction.

First records of Chrysocyon brachyurus (Illiger, 1815) (Mammalia, Carnivora) in the Gualeguay Department, Entre Ríos Province, Argentina

The maned wolf (Chrysocyon brachyurus, Illiger 1815) is the largest canid in South America. The objective of this work is to present a new border registry of Chrysocyon brachyurus, in the Department of Gualeguay, Province of Entre Ríos (32°59'51.78''S, 59°30'59.12''W); validate its membership in that taxon through the use of the COI molecular marker and review and comment on recent reports of specimens recorded further south of the known range of the species in a conservation context.

The value of a small urban green area to the medium and large-sized mammals conservation

Brazil presents the biggest mammal diversity in the world, 755 species, of which 110 are classified under some degree of threat. In the São Paulo State is an estimated 350 taxa richness, however, this number can be even higher due to the gap of sampling over large extensions. In addition, many urban green areas are not studied because their value is underestimated for biodiversity conservation. In this way, the present study aimed to survey the medium and large-sized terrestrial mammals in a Municipal Conservation Unit located in the urban area of Franca, SP. Using cameras trap, sand plots, and active search, in the period between May and July 2019, 16 mammals were sampled. The highest number of species was identified through sand plots (12), followed by active search (7) and cameras trap (4). The sampled community is mostly composed of opportunistic and generalist species with few predators. Among species found, the maned wolf (Chrysocyon brachyurus) is classified nationally as vulnerable to extinction. Despite the significant number of sampled species, the species accumulation curve obtained did not reach its asymptote. Thus, it is concluded that Zoobotanic Garden, despite suffering strong anthropic pressure, develop an important role in the regional medium and large-sized terrestrial mammals conservation, acting as a refuge area for these species.