Considering the importance of leptospirosis in both equine husbandry and public health, as well as the relevance of knowledge of current serogroup and the small number of studies addressing this disease in equines in Northeastern Brazil, the present study performed a serological survey of Leptospira spp. in a serum bank of 1,267 equines originating from 177 municipalities, located in four states in Northeastern Brazil: Ceará, Rio Grande do Norte, Paraíba and Pernambuco. The microscopic agglutination test (MAT) was used for diagnosis of leptospirosis using 24 serovars as antigens. The frequency of reagent equines was 29.7% (376/1,267), and 68.9% (122/177) of municipalities had at least one positive reaction. The serogroups reagent were Australis (37.2%), Icterohaemorrhagiae (29.3%), Tarassovi (9.6%), Sejroe (5.8%), Pomona (5.3%), Grippotyphosa (4.5%), Pyrogenes (2.4%), Bataviae (1.9%), Ballum and Hebdomadis (1.3%), Mini (0.5%), Celledoni, Shermani, and Javanica (0.3% each). There were significant statistical differences regarding sex and age, with a higher frequency in females (P= 0.014), and in animals ≥ 6 years (P=0.001). We concluded that seropositivity to Leptospira spp. is high in equines in Northeastern Brazil, with a predominance of serologic reactions to the Australis serogroup in the border areas between the states, and the Icterohaemorrhagiae serogroup in coastal areas or their vicinity. The high degree of seropositivity found points to the need to implement prophylactic strategies, both intraspecies infection prophylaxis and rodent control. We also recommended avoiding animal crowding and separating animals according to sex and age group during handling.

The objective of this study was to detect the presence of anti-Toxoplasma gondii antibodies in serum samples from 100 sparrows (Passer domesticus Linnaeus, 1758) that were caught in an urban area in southern Brazil. The modified agglutination test (MAT) was used to investigate anti-T. gondii antibodies and samples with a cut-off dilution > 5 were considered positive. Among the 100 serum samples analyzed, 80 (80%) were reactive. These results demonstrate that P. domesticus may play an important role in the epidemiological chain of T. gondii, since it is widely distributed throughout Brazil, and it may act as a source of infection to domestic, semi-domestic cats and to free-living wild felids.

The occurrence of leptospirosis is significantly higher in the tropical climate than in temperate regions, especially in periods with high rainfall levels. In horses, leptospirosis can range from subclinical to asymptomatic but maintains an important role in the transmission of leptospirosis by eliminating the agent in the environment. Regarding horses, the Amazonas herd increased by 30% between 2004 and 2013. Thus, the study aimed to determine the serological prevalence of leptospirosis in horses in Manaus and metropolitan regions, in the State of Amazonas, Brazil as well as to assess the main serogroups involved in the infections of these animals. For this purpose, from August 2018 to July 2019, serum from 198 horses was evaluated through the microscopic agglutination test with a panel of 10 serogroups. As a result, 92 horses (44.46%) were found to be positive for one or more Leptospira serovars, with the highest prevalence of serogroups Icterohaemorrhagiae and Pyrogenes. Therefore, with the increase in the equine herd in the region and, consequently, greater interaction between breeders and animals, the identification of reagents to at least one serovar of Leptospira spp. signals the possible existence of reservoirs of pathogenic strains for other animals and man.