Risk factors for Toxoplasma gondii infection in sheep and cattle from Fernando de Noronha Island, Brazil

Abstract

Toxoplasmosis is a zoonotic disease of global distribution that affects all warm-blooded animals. The purpose of this investigation was to determine the prevalence of T. gondii infection and identify the risk factors associated with its occurrence in domestic ruminants raised on the island of Fernando de Noronha, Brazil, and to confirm that cattle and sheep raised in Fernando de Noronha Island present statistically different T. gondii prevalence rates. Serum samples were collected from sheep (n=240) and cattle (n=140) for the detection of antibodies by indirect immunofluorescence. Samples were collected from all the animals on all the farms. Risk factors were analyzed by univariate analysis and logistic regression. The prevalence rate of positive sheep was 85.0% while that of cattle was 10.7%. A multivariate analysis revealed that the site of contact of sheep with felines was a risk factor. For cattle, the risk factors identified in this study were: extensive farming system, water source, more than three cats per farm, and the presence of rats in feed storage locations. The findings revealed a significant difference in the prevalence rates in sheep and cattle raised in this insular environment.Keywords: Ruminants, toxoplasmosis, epidemiology. ResumoA toxoplasmose é uma zoonose cosmopolita que acomete animais de sangue quente. Objetivou-se nessa investigação determinar a prevalência e identificar os fatores de risco associados à ocorrência da infecção por T. gondii em ruminantes domésticos criados na Ilha de Fernando de Noronha e demonstrar que bovinos e ovinos criados na ilha de Fernando de Noronha, Brasil, apresentam prevalências estatisticamente distintas. Foram obtidas amostras de soro sanguíneo de todos os ovinos (n=240) e bovinos (n=140) de todas as propriedades da ilha para a pesquisa de anticorpos na Reação de Imunofluorescência Indireta. Os fatores de risco foram analisados por meio da análise univariada e regressão logística. A prevalência de ovinos reagentes foi de 85,0% e 10,7% para bovinos, que foram significativamente diferentes. Na análise multivariada, local de contato de ovinos com outras espécies foi identificado como fator de risco. Para os bovinos, os fatores de risco foram: sistema extensivo, fonte de água, número de gatos nas propriedades e a presença de rato. Os resultados obtidos demonstram diferença significativa nas prevalências em ovinos e bovinos criados neste ambiente insular.Palavras-chave: Ruminantes, toxoplasmose, epidemiologia.

Evaluation of the Effects of Toxoplasmosis in Small Ruminants on the Epidemiology of Human Toxoplasmosis by Indirect ELISA in Kaleybar Region, North West of Iran

“…Some studies including those conducted by Bahrieni et al on small ruminants in southeastern Iran (46), de Moura et al on goats in Brazil (47), and Gebremedhin et al on sheep in Ethiopia (48) show that susceptibility to toxoplasma is higher in females than in males. However, in the current study, no statistically significant relationship was found between gender and the seroprevalence of toxoplasmosis (0.276), which is consistent with many other studies (49)(50)(51)(52)(53). It seems that gender does not appear to play an important role in toxoplasmosis, and in epidemiological studies, it is considered as a confounding factor (54).…”

Seroprevalence, spatial distribution and risk factors associated with Toxoplasma gondii infection among cattle in a quilombola community in the Brazilian cerrado

“…The presence of anti-T. gondii antibodies in 8.93% (95% CI: 7.55%-10.47%) of the cattle demonstrates that the prevalence of infection in the Brazilian central Cerrado region is close to that observed in both the far western part of Brazil (11.8%) (Souza et al, 2016) and in the island portion, in the far east, in the Atlantic islands of Fernando de Noronha (10.7%) (Magalhães et al, 2016). This corroborates the copious capacity for dissemination and adaptability of the parasite (Tenter et al, 2000).…”

“…Anti-bovine IgG antibodies produced in rabbit (Sigma, St. Louis, USA) were used as a conjugate. A cut-off point at a dilution of 1:64 was established (Magalhães et al, 2016;Souza et al, 2016). IFAT slides were examined by means of fluorescence microscopy using an epifluorescence microscope (Olympus Bx 51, Olympus Inc., Tokyo, Japan) at 40x magnification.…”

Toxoplasma gondii in cattle in Brazil: a review

“…Host feeding behavior has also been correlated with the risk of infection among humans and animals (Robert-Gangneux, 2014). For cattle, which tend to feed on the higher portions of the pasture grass, the possibility of oocyst intake is lower than for sheep, for example, which graze on grasses that are close to the ground (Magalhães et al, 2016).…”

“…These animals can enter the pastures and share the same water source as used by the cattle, thus increasing the cattle's exposure to the parasite through dissemination of oocysts in the environment. On Fernando de Noronha, an Atlantic island in the state of Pernambuco, Brazil, Magalhães et al (2016) showed that the exposure of cattle to T. gondii was related to extensive rearing. On this island, T. gondii antibodies were detected in 66% of the feral cats (Costa et al, 2012).…”