RESUMEN
Bovine Genital Leptospirosis (BGL) is an important reproductive disease. The main agents are Sejroe strains, particularly the Hardjo genotypes from Leptospira interrogans and L. borgpetersenii. Although other Sejroe strain, L. santarosai genotype Guaricura, has been frequently isolated from asymptomatic and slaughtered cattle, even from vaginal fluid samples, the role of this strain as real agent of BGL remains uncertain. This study aimed to reinforce L. santarosai strain Guaricura as an important BGL agent, through genetic characterization of a uterine isolate from a live subfertile cow. Urine, cervicovaginal mucus (CVM) and uterine fragment (UF) were collected. In a set up field laboratory, urine, CVM and UF were immediately seeded in T80/40LH medium with antimicrobial cocktail STAFF. Cultures were subcultured in T80/40LH without cocktails, stored at 29ºC and weekly examined. DNA from urine, CVM and UF samples were submitted to PCR targeting lipL32 and secY genes. One leptospiral isolate was recovered from uterine sample; it was serogrouped as Sejroe (titre 25,600) and secY sequencing revealed high genetic similarity with L. santarosai strains from Guaricura serovar. The isolation of this strain from uterus of a live subfertile cow represents substantial evidence that L. santarosai strain Guaricura indeed plays an important role as a BGL agent.
Asunto(s)
Enfermedades de los Bovinos , Leptospira , Leptospirosis , Animales , Bovinos , Femenino , Leptospira/genética , Leptospirosis/veterinaria , Serogrupo , ÚteroRESUMEN
Swine genital leptospirosis is an infectious disease that leads to economic losses due to abortions, stillbirths, and reproductive failures. Considering the scarcity of studies regarding this condition, the objective of the present study was to identify and analyse leptospires infecting the reproductive tract of female pigs slaughtered in the Amazon region. Cervical-vaginal mucus (CVM) from 150 non-pregnant females were collected and submitted to molecular analysis. Initially, polymerase chain reaction (PCR) based on the lipL32 gene was performed. A total of 26.7% (40/150) samples were positive, indicating the presence of Leptospira sp. DNA. Subsequently, positive lipL32-PCR samples were evaluated using secY nested-PCR and sequencing procedures. Eleven amplicons could be sequenced and were identified as Leptospira interrogans (100% identity). Results from phylogenetic analyses led to identification of a putative strain of L. interrogans serogroup Australis, which is indicative of this being a serogroup. In the present study, there was detection of female pigs with leptospires in CVM indicating the possibility of venereal transmission. The large number of genital positive cases could indicate that genital leptospirosis syndrome could also be relevant onto swine production.