Anti-Toxoplasma gondii and anti-Neospora caninum antibodies in sheep from Paraná state, South Brazil: prevalence and associated factors

Abstract

The aim of this study was to evaluate the seroprevalence and factors associated with the presence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies in sheep from Paraná state. The detection of antibodies for T. gondii and N. caninum was performed by homemade and commercial indirect ELISA, respectively. Multiple logistic regression analysis was used to verify the factors associated with the seroprevalence. Antibodies anti-T. gondii and anti-N. caninum were observed in 42.7% and in 17.6% of the animals, respectively. The protective factors associated to seropositive were “some level of confinement” (full or semi-extensive confinement) (OR=0.53) for T. gondii and “use of skilled labor” (OR=0.64) for N. caninum. The risk factors were “presence of cats” (OR=1.75) for T. gondii and “feeding of dogs with sheep placental remains” (OR=1.79) for N. caninum. In addition, to presenting a significant and simultaneous seroprevalence for both agents (9.9% of the animals), the results also indicate that deficiencies in management and environmental sanitation, the presence of reservoirs, and types of exploitation enhance the seropositivity. Thus, studies like this might support sanitary programs and public policies for the prevention of T. gondii and N. caninum in the sheep herds of Paraná state.

Dynamics of Neospora caninum-Associated Abortions in a Dairy Sheep Flock and Results of a Test-and-Cull Control Programme

“…Although seroprevalence studies indicate that N. caninum infection is present in small ruminants worldwide [1,15,25,26], the impact of ovine neosporosis is still unknown, and only a few case reports of N. caninum associated abortions have been published [5][6][7]. On the other hand, previous experiences of controlling ovine neosporosis are scarce [8].…”

“…However, recent evidence suggests that N. caninum is also linked to abortion and neonatal mortality in sheep [5,7,8,10]. Most of the studies focused on N. caninum in sheep have investigated the seroprevalence by sampling a representative number of animals from several flocks [13,15,29,30] or testing for N. caninum DNA presence in aborted foetuses from several flocks [17,20,31,32]. However, only one study addressed the relationship between N. caninum serostatus and reproductive performance in a sheep flock [8].…”

“…The occurrence of abortions [12,13] and stillbirths [14] have been statistically associated with N. caninum infection in sheep. The presence of dogs [13], the consumption of placental tissues by dogs [15], and the rearing system [16] have been identified as main risk factors for N. caninum infection in ovine flocks.…”

Ovine Neosporosis: The Current Global Situation

“…For example, animal seroprevalence rates in Brazil have been found to be as low as 1.8% and as high as 60.6% in the states of Rio do Norte (northeastern) and Rondonia (western), respectively [ 83 , 103 ]. In general terms, serological studies carried out in the American continent were restricted to Latin and Central American countries—mainly Brazil (29/37) ( Table 1 ), which had an overall seroprevalence of 19.9% (from a total of 15,461 serum samples tested)—and it has been suggested that deficiencies in environmental management and sanitation that could favor the dissemination of N. caninum in the sheep flocks may be responsible for this high seroprevalence [ 104 ].…”