Leptospirosis in native mixed-breed sheep slaughtered in a semiarid region of Brazil

Farías

et al. 2018

Trop Anim Health Prod

Although some studies in sheep have indicated leptospire colonization of the genital tract, further studies are needed to clarify the role of genital carriers in this species. Thus, this study aimed to evaluate the colonization of pathogenic leptospires in the genital and urinary tract of slaughtered sheep. Fifty-seven adult, female woolless sheep destined for slaughter were used. Renal (n = 57), bladder (n = 57), ovary (n = 34), uterine tube (n = 44), and uterus (n = 33) samples were collected for molecular detection of Leptospira sp. DNA, and blood samples (n = 57) for serological testing. The molecular testing was performed using polymerase chain reaction (PCR), and the serological testing was performed using microscopic serum agglutination test (MAT). Samples with amplifying DNA were subjected to genetic sequencing. In total, leptospiral DNA was found in the tissues of 44 (77.2%) sheep, whereas only nine animals were positive on both PCR and MAT; there was slight agreement between PCR and MAT techniques (k = 0.0268; p = 0.684). In 61 (54.9%) genital tract and in five (4.4%) urinary tract samples, the leptospiral DNA was detected, with significant difference (p < 0.001). The genes of one sample from the uterine tube and another from the bladder were sequenced and demonstrated 99% similarity to Leptospira interrogans. Anti-Leptospira antibodies were detected in 11 (19.3%) of the tested animals. The results reinforce the importance of the genital tract as an extra-renal site of colonization, suggesting the possibility of venereal transmission in sheep.

Section: Discussionsupporting

confidence: 57%

High frequency of genital carriers of Leptospira sp. in sheep slaughtered in the semi-arid region of northeastern Brazil

Farías

et al. 2018

Trop Anim Health Prod

“…This study found high occurrences in Icterohaemorrhagiae and Autumnalis, with 25.21% occurrences in the former and 31.09% occurrences in the latter, which is a recurrent fact in studies related to animals in the Northeast (Costa et al, 2017;Moraes et al, 2019). This is an important fact, as it brings worries to human and animal health, once leptospirosis can also occur in occupational form, and these serogroups are important to the disease cycle in humans, especially to those in contact with the animals and their fluids, such as agricultors, slaughterhouse workers and veterinarians (Dorjee et al, 2008;Adler & De La Peña Moctezuma, 2010), and it was observed the presence of the disease in both biomes, despite their differences in soil and climate, suggesting a relation between the region studied and the occurrence of these serogroups.…”

Section: Discussionsupporting

confidence: 50%

Epidemiological survey for goat leptospirosis in two distinct biomes in Northeastern Brazil

Viana

Lima

et al. 2021

RSD

Self Cite

Caprine breeding is a largely exploited activity in Brazil, with a herd of over 10 million goats concentrated mostly in the Northeast region, which contains 93.9% of the national herd. However, this region is affected by huge losses due to inappropriate management and illness occurrence, such as leptospirosis, a reproductive disease that causes economic and productive losses. Considering these previous statements, we aimed to determine the most frequent seroprevalence, serogroups and factors associated with the occurrence of leptospirosis in goats from different states and biomes of the Brazilian northeast and properly locate the disease throughout the region through the analysis of epidemiological questionnaires and geographic data. The samples were submitted to the Microscopic Agglutination Test (MAT) with a cutoff of 50. In addition, geographic data were analysed to create maps with epidemiological descriptions of the disease in the states. The total occurrence of seropositive animals was 19.93% (119/597), 18.92% (35/185) in the state of Alagoas and 20.38% (84/412) in Maranhão. The most common serogroups in these states were Autumnalis (31.09%) and Icterohaemorrhagiae (23.81%). Dividing the results, it was possible to observe a greater occurrence of the serogroup Autumnalis (42.86%) Icterohaemorrhagiae (28.57%) in the state of Alagoas, Caatinga biome, plus Autumnalis (26.19%) and Icterohaemorrhagiae (23.81%) in the state of Maranhão, Cerrado biome. It was proven that Leptospira sp. is present in both states and biomes analyzed, present in diverse areas as in vegetation and climate, warning preventive care towards the disease.

“…Studies have reported the predominance of low titers of anti- Leptospira antibodies associated with infection in sheep flocks or samples from a slaughterhouse [15, 16, 17]. However, the microscopic agglutination test (MAT) used for serological diagnosis is not considered an adequate method to identify carriers at the individual level, since infected animals may have low or undetectable titers, necessitating the use of direct diagnostic methods for detection of carriers [18].…”

Section: Introductionmentioning

confidence: 99%

Investigation of chronic infection by Leptospira spp. in asymptomatic sheep slaughtered in slaughterhouse

et al. 2019

The study aimed to evaluate the histopathological characteristics of renal lesions in chronically infected sheep and with low titers of anti- Leptospira antibodies from a slaughterhouse. In the serological analysis, 24.74% (48/194) presented seroreactivity with a titer equal to or greater than 100. Among these seroreactive sheep, titers of 100 were predominant (58.33%, 28/48), with the highest titer being 1,600 (2.08%, 1/48). Serogroup Sejroe (sv. Hardjo) was the most frequent at 35.42% (17/48). Leptospiral DNA was verified in 4.12% (8/194) of the kidney samples tested, and no urine sample was positive. All the samples corresponded to the pathogenic species L . interrogans . The eight amplicons with 202-nucleotides were identical with two mismatches (presented 100% of identity) using the PCR targeting to secY gene. Histological sections of PCR-positive kidneys were submitted to direct detection by the anti-LipL32 immunohistochemistry (IHC) technique. The Leptospira spp. antigen was evident in 62.5% (5/8) of the kidneys. Positive staining was observed in the cytoplasm of tubular cells and in the form of brownish aggregates that adhered to tubular epithelial cells and projected into the lumen. Inflammatory lymphoplasmacytic infiltrate, ranging from mild to moderate, with multifocal distribution, was the predominant finding in seroreactive animals (33.33%, 16/48). The demonstration of the leptospiral antigen lining the renal tubules through IHC of naturally infected sheep confirmed by PCR characterizes renal colonization in a species with the presence of histological changes compatible with leptospirosis.