RESUMO

Background: Neosporosis is a cosmopolitan disease known as the main infectious cause of abortion in cattle, reported in several states in Brazil. The transplacental transmission in cattle is responsible for perpetuating the disease in the herd. In the state of Santa Catarina, previous studies on this protozoan in cattle are mostly serological surveys. To increase information about this reproductive disorder, this work describes the diagnosis of abortions due to Neospora caninum in dairy cattle from state of Santa Catarina and the follow-up for 4 years in a farm affected by neosporosis. Cases: From 2015 to 2019, necropsy was performed on 10 aborted bovine fetuses, between fifth and eighth month of pregnancy, with 1 fetus aborted in 2015, 3 in 2016, 2 in 2017 and, 4 in 2019, all originating from the same dairy property in the southern region of state of Santa Catarina. No macroscopic lesions were found. Histopathology revealed mild to moderate multifocal mononuclear necrotizing encephalitis in 5 fetuses, and multifocal mild mononuclear myositis and myocarditis in 4 and 3 fetuses, respectively. Polymerase Chain Reaction (PCR) using primers based on the Nc-5 gene was positive for N. caninum in five fetuses. Three visits were performed in the farm for epidemiological evaluation and blood samples collection for IgG antibodies anti-N. caninum (IFAT). The total herd was 170 Jersey, Holstein and crossbred cattle, raised in a semi-confined system with mechanical milking system. Since 2014, there has been a significant increase in abortions cases, approximately 20 cows had abortions; in the year 2015, approximately 10; in 2016, less than 5; in 2017, 4 cows aborted; in 2018, 11 abortions and, in 2019, there were 4 abortions. An increase in the rate of return to estrus was also reported, and both primiparous and multiparous cows had reproductive disorders. Abortions were recorded throughout the year and occurred predominantly between the fourth and sixth month of pregnancy. In 2016, an Indirect Immunofluorescence Reaction (IFAT) was performed on sera from 26 cows (13 with a history of reproductive disorders and another 13 without disorders). Of these, 50.0% (13/26) were seropositive, with titers ranging from 100 to 1600 (cutoff ≥100). The Enzyme Immunoassay (ELISA) of the entire herd was carried out in 2017, with 26.54% (43/162) of seropositivity, 8.02% (13/162) suspect, and 30.4% (17/56) had reproductive disorders. It was observed that only animals born on the property were used for replacement, there was less possibility of direct contact between dogs on the property with milking facilities, placental and fetal remains, properly disposing of these, incinerating or burying. Thirty animals were discarded from the property, 25 of which had reproductive disorders. All young female daughters of seropositive cows remained on the property for replacement. During the evaluation period, all dogs were eliminated. Discussion: In this study, the diagnosis of neosporosis was made through epidemiology, histopathological lesions characterized by mononuclear encephalitis, myocarditis and myositis, and detection of the agent by PCR, associated with serological techniques. The lesions observed are indicative of N. caninum infection and are compatible with lesions observed in other studies. Serological screening is important to complement the diagnosis of abortion by N. caninum and to help control the agent in herds. From this report it is concluded that N. caninum is an important agent of reproductive disorders in cattle in the southern region of Santa Catarina, the different serological analyzes showed a good screening index for the inclusion of control strategies. In addition, the monitoring of reproductive rates of affected properties becomes necessary over the years, allowing better observation of control strategies.

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RESUMO

Este estudo teve como objetivo descrever casos de abortamento por leptospirose em éguas, ocorrido no município de Mossoró, Rio Grande do Norte. Cinco éguas com histórico de abortamento foram submetidas a exames clínicos, hematológico e pesquisa de aglutininas anti-Leptospira para 22 diferentes sorovares, pelo Teste de Soroaglutinação Microscópica (SAM). Foi realizado exame anatomopatológico da placenta e de um feto equino abortado com 9 meses de idade. A infecção por Leptospira sp. ocorreu em três éguas que abortaram, sendo uma positiva para o sorovar Pomona, título 800; uma para o sorovar Hardjo, título 400; uma para o sorovar Icterohaemorrhagiae, título 400. No exame anatomopatológico da placenta foram observados cotilédones edemaciados de coloração vermelho escuro, com áreas focais enegrecidas, friáveis e necróticos. No exame necroscópico do feto observou-se icterícia, presença de líquido sero-sanguinolento na cavidade abdominal, torácica e saco pericárdico, áreas multifocais de hemorragia no fígado, coração e pulmão, rins de consistência friável e áreas multifocais branco amareladas. Histologicamente, verificou-se necrose e inflamação do epitélio placentário coriônico; necrose difusa de hepatócitos e hepatite mononuclear; acentuada hemorragia no interstício do córtex renal, degeneração hidrópica e necrose das células do epitélio tubular e presença de cilindros hemáticos intratubular; além de nefrite intersticial mononuclear e pneumonia intersticial mononuclear difusa acentuada. Os resultados deste estudo demonstraram títulos elevados de aglutininas anti-Leptospira em éguas e a presença de lesões histológicas nos órgãos fetais e placenta, confirmando a importância da Leptospira como agente causador de abortamento

This study aimed to describe cases of leptospirosis abortions in horses, which occurred in the city of Mossoró, Rio Grande do Norte. Five mares with abortion history, were submitted to clinical, hematological and detection of specific anti-Leptospira agglutinins facing 22 different serotypes, by Microscopic Agglutination Test (MAT). It was performed a pathological examination of the placenta and an equine aborted fetus with 9 months old. The Leptospira sp. infection occurred in three mares that aborted. One was positive for Pomona, title 800; one for the Hardjo serovar, title 400 and one for Icterohaemorrhagiae serovar, title 400. In examination of the placenta were observed swollen cotyledons, dark red color with blackened focal areas, friable and necrotic. In the fetus's autopsy was observed icterus, serous-sanguineous fluid in the abdominal cavity, chest and pericardium, multifocal areas of hemorrhage in the liver, heart, lungs, and friable multifocal yellowish white areas in the kidney. Histologically, it was found necrosis and inflammation of the placental chorionic epithelium; diffuse necrosis hepatocyte and mononuclear hepatitis; severe hemorrhage in the interstitium of the renal cortex, hydropic degeneration and necrosis of the tubular epithelial cells and the presence of haematic intratubular cylinders; mononuclear interstitial nephritis and a severe diffuse interstitial mononuclear pneumonia. The results showed high levels of anti-Leptospira agglutinins in mares and presence of histological lesions in the placenta and fetal organs, confirming the importance of Leptospira as abortion-causing agent.

Assuntos

RESUMO

This study aimed to describe cases of leptospirosis abortions in horses, which occurred in the city of Mossoró, Rio Grande do Norte. Five mares with abortion history, were submitted to clinical, hematological and detection of specific anti-Leptospira agglutinins facing 22 different serotypes, by Microscopic Agglutination Test (MAT). It was performed a pathological examination of the placenta and an equine aborted fetus with 9 months old. The Leptospira sp. infection occurred in three mares that aborted. One was positive for Pomona, title 800; one for the Hardjo serovar, title 400 and one for Icterohaemorrhagiae serovar, title 400. In examination of the placenta were observed swollen cotyledons, dark red color with blackened focal areas, friable and necrotic. In the fetuss autopsy was observed icterus, serous-sanguineous fluid in the abdominal cavity, chest and pericardium, multifocal areas of hemorrhage in the liver, heart, lungs, and friable multifocal yellowish white areas in the kidney. Histologically, it was found necrosis and inflammation of the placental chorionic epithelium; diffuse necrosis hepatocyte and mononuclear hepatitis; severe hemorrhage in the interstitium of the renal cortex, hydropic degeneration and necrosis of the tubular epithelial cells and the presence of haematic intratubular cylinders; mononuclear interstitial nephritis and a severe diffuse interstitial mononuclear pneumonia. The results showed highlevels of anti-Leptospira agglutinins in mares and presence of histological lesions in the placenta and fetal organs, confirming the importance of Leptospira as abortion-causing agent.(AU)

Este estudo teve como objetivo descrever casos de abortamento por leptospirose em éguas, ocorrido no município de Mossoró, Rio Grande do Norte. Cinco éguas com histórico de abortamento foram submetidas a exames clínicos, hematológico e pesquisa de aglutininas anti-Leptospira para 22 diferentes sorovares, pelo Teste de Soroaglutinação Microscópica (SAM). Foi realizado exame anatomopatológico da placenta e de um feto equino abortado com 9 meses de idade. A infecção por Leptospira sp. ocorreu em três éguas que abortaram, sendo uma positiva para o sorovar Pomona, título 800; uma para o sorovar Hardjo, título 400; uma para o sorovar Icterohaemorrhagiae, título 400. No exame anatomopatológico da placenta foram observados cotilédones edemaciados de coloração vermelho escuro, com áreas focais enegrecidas, friáveis e necróticos. No exame necroscópico do feto observou-se icterícia, presença de líquido sero-sanguinolento na cavidade abdominal, torácica e saco pericárdico, áreas multifocais de hemorragia no fígado, coração e pulmão, rins de consistência friável e áreas multifocais branco amareladas. Histologicamente, verificou-se necrose e inflamação do epitélio placentário coriônico; necrose difusa de hepatócitos e hepatite mononuclear; acentuada hemorragia no interstício do córtex renal, degeneração hidrópica e necrose das células do epitélio tubular e presença de cilindros hemáticos intratubular; além de nefrite intersticial mononuclear e pneumonia intersticial mononuclear difusa acentuada. Os resultados desteestudo demonstraram títulos elevados de aglutininas anti-Leptospira em éguas e a presença de lesões histológicas nos órgãos fetais e placenta, confirmando a importância da Leptospira como agente causador de abortamento.(AU)

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