Publications by authors named "Jenevaldo B da Silva"

The present study aimed to describe the occurrence of Borrelia spp. in cattle in the states of Minas Gerais and Pará in southeastern and northern Brazil, respectively. Bovine whole blood samples were examined by blood smear and polymerase chain reaction (PCR) to detect the flagellin B (flaB) gene of Borrelia spp.

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This study aims to evaluate the infection's clinical parameters and genetic diversity of msp1α of the AmRio1 strain in acute and chronic infections in cattle and ticks. A calf experimentally infected with the A. marginale AmRio1 strain was monitored during acute infection, and the presence of the msp1α gene was verified in the semi-nested polymerase chain reaction (PCR) during the acute and persistent phases of infection.

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The objective of this study was to determine the prevalence of antibodies to Neospora caninum and Toxoplasma gondii among 500 cattle (Bos indicus) and 500 buffaloes (Bubalus bubalis) using the indirect fluorescent antibody test (IFAT) technique. Blood samples from were collected from water buffalo and cattle in 10 municipalities in the northern region of Brazil. The frequency of cattle and water buffaloes seropositive for Neospora caninum in Pará state, Brazil, was 55% and 44%, respectively, and the frequency of cattle and water buffaloes seropositive for Toxoplasma gondii was 52% and 39%, respectively.

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The present study reports the genetic diversity of Anaplasma marginale during anaplasmosis outbreaks in rural properties of the states of Goiás and São Paulo, Brazil. Mortality rates of 3.5% (37/1,050) in calves, 4.

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Major surface protein 1a has been used as a marker for genetic stability in identifying geographical isolates of Anaplasma marginale. We conducted a longitudinal study to ascertain the genetic diversity of A. marginale in a dairy cattle herd with a history of clinical anaplasmosis.

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Anaplasma marginale is the most prevalent pathogen transmitted by ticks in cattle in tropical and subtropical regions of the world. However, the tick species involved in the transmission of A. marginale in buffaloes in Brazil have not been identified.

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Article Synopsis
  • Tuberculosis poses a significant threat to cattle production, causing economic losses and having a zoonotic potential.
  • A study in Pará, Brazil, tested 1140 buffaloes using a comparative cervical test (CCT), revealing 4.65% positive cases for tuberculosis, with additional inconclusive and negative results.
  • The findings suggest that CCT is an effective diagnostic tool, with good sensitivity (71.43%) and specificity (82.61%), indicating a low prevalence of Mycobacterium bovis among the tested buffaloes.
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The establishment of laboratory colonies of ticks is often hampered by their lack of adaptation to alternative hosts. The aim of this study was to artificially feed partially engorged Dermacentor (Anocentor) nitens females through plastic tips, and to identify what are the optimal conditions of application of this technique to get as much as possible close to the natural conditions. The technique of artificial feeding through plastic tips allowed the engorgement of D.

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This study aimed to evaluate season, breed, number of lactations and milk production as risk factors relating to Rhipicephalus microplus infestation in dairy cows during the peripartum. Eighty-four animals were randomly selected through proportional stratified sampling. All engorged and partially engorged female R.

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Article Synopsis
  • The study investigates the prevalence of various parasitic diseases in water buffaloes in northern Brazil, focusing on Toxoplasma gondii, Neospora caninum, Anaplasma marginale, Babesia bigemina, and Babesia bovis.
  • A total of 4,796 blood samples from buffaloes across five provinces were analyzed using two methods: IFAT and ELISA, revealing significant serological prevalence rates for the diseases.
  • The findings provide crucial data for managing and controlling these bovine pathogens, which is essential for the health of the buffalo population in the region.
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The prevalence of and possible risk factors for tuberculosis were studied in water buffalo from Pará, Brazil. In this study, 3,917 pregnant and nonpregnant female Murrah and Mediterranean buffaloes were studied; 2,089 originated from Marajó Island, and 1,108 were from the mainland. The comparative cervical tuberculin test was used as a diagnostic test for tuberculosis in these animals.

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Anaplasma marginale is endemic in tropical and subtropical areas around the world. Some studies have suggested that cows during peripartum may present a transient immunosuppression state and development of clinical signs of anaplasmosis. The aim of this study was to investigate the relationship between some risk factors and the seroprevalence of A.

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To evaluate the prevalence and possible risk factors for brucellosis caused by Brucella abortus in water buffaloes in the state of Pará, Brazil, 3,917 female buffalo serum samples from pregnant and non-pregnant animals were examined: 2,809 from Marajó Island and 1,108 from the mainland. The buffered acidified plate antigen (BAPA) screening test positively diagnosed 4.8% (188/3,917) of the animals with brucellosis, and the 2-mercaptoethanol (2-ME) confirmatory test affirmed 95.

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Bovine babesiosis is a tick-borne disease caused mainly by Babesia bovis and Babesia bigemina, which are associated to considerable economic losses in cattle herds worldwide. Approximately 60% of buffalo herds in South America are located in Northern Brazil. Little is known about the impact of babesiosis on buffalo herds in Brazil.

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The purpose of this study was to identify the influence of physiological state, season, breed, number of lactations, dairy productivity, and stocking rate on infestation by Rhipicephalus microplus in dairy cows. Two hundred cows were selected through proportional representative sampling at the Seropédica Experimental Station (Pesagro-Rio), Brazil. Fully or partially engorged R.

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The current study aimed to investigate the seroprevalence of IgG antibodies to Anaplasma marginale in cattle from Maputo, Gaza and Inhambane provinces, south Mozambique. A total of 809 serum samples from cattle were obtained and tested by indirect enzyme-linked immunosorbent assay (i-ELISA). The chi-square test at 5% significance was used to assess the association between seroprevalence and the variables gender, age and geographic origin of animals.

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Artificial feeding is an important toll for studying ticks feeding mechanism and transmission of pathogenic agents in the absence of vertebrate host. The objective was to feed artificially of engorged partially females of Dermacentor (Anocentor) nitens, proceeding of infested naturally equines and evaluate the influence of this technique on biological parameters of species. Engorged partially females were collected, weighted and separate by weight in two range of 40 to 60 milligrams and 61 to 100 milligrams.

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