EFFECT OF DIFFERENT ECOSYSTEMS AND MANAGEMENT PRACTICES ON TOXOPLASMA GONDII AND NEOSPORA CANINUM INFECTIONS IN WILD RUMINANTS IN SPAIN.

Toxoplasma gondii and Neospora caninum are two major abortifacient protozoans in domestic small ruminants and cattle, respectively, and they also parasitize a wide range of wildlife. Numerous serosurveys have been conducted in wild ruminants worldwide. However, the potential effect of different ecosystems and management practices on these infections has not been investigated. We studied the prevalence of antibodies to T. gondii and N. caninum in wild ruminants between 2007 and 2012 from four national wildlife reserves: three open space reserves in northwest Spain (Ancares, Mampodre, and Riaño) and a fenced reserve in central Spain (Quintos de Mora). Sera from roe deer ( Capreolus capreolus ) and chamois ( Rupicapra rupicapra ) were collected in Ancares (roe deer), Mampodre (both species), and Riaño (both species), whereas red deer ( Cervus elaphus ) sera were collected only in Quintos de Mora. The results of immunofluorescence antibody tests showed a T. gondii antibody prevalence significantly higher in red deer (13%; 17/131) than in roe deer (2%; 5/228) and chamois (4%; 6/149) (P<0.05, Fisher's exact test). Moreover, N. caninum -specific antibodies were only detected in 1% of animals (2/131 red deer, 2/228 roe deer, and 2/149 chamois). Management measures were implemented in the Quintos de Mora reserve and T. gondii antibody prevalence in red deer decreased from 13% to 2% after 5 yr. In contrast, N. caninum antibody prevalences were very low (<2%) over the years. The results suggest a low frequency of sylvatic life cycles in the hunting reservations studied, so interconnection between sylvatic and domestic life cycles is unlikely. Regardless, a sustainable exploitation of natural resources in wildlife reserves may help to reduce the prevalence of T. gondii infection.

Nodular onchocercosis of red deer in central Spain.

The presence of nodular onchocercosis was investigated post-mortem in 142 red deer (11 calves, 35 yearlings and 96 adults) shot from February 1998 to January 1999, and July-November 1999 in "Quintos de Mora" (Toledo, central Spain), a game property belonging to the National Wildlife Reserves. Between 6 and 13 animals were analysed monthly by inspection for subcutaneous nodules of Onchocerca spp. Subcutaneous nodules of Onchocerca sp. were detected in 24% of the animals. Anatomical locations for nodules were the back and flanks. Infection ranged from 1 to 29 nodules per animal. Adult worms collected from nodules were identified as O. flexuosa. No apparent seasonal trend was observed either in prevalence or in mean intensity of infection, which fluctuated between 48% (5+/-8 nodules) in winter 1998 and 5% (1+/-0 nodules) in summer 1999. Prevalence of infection was significantly higher in adult (30%) than in young animals (9% in calves, 11% in yearlings), although no age effect on intensity was observed. The size of the nodules was measured to evaluate the age of infection. Small (recent) nodules (5-6mm of diameter) were collected in late spring, summer and fall; medium-sized nodules (12-15 mm) were in second half of summer, fall and winter, and large (mature) nodules (20-25 mm) in fall, winter and part of spring. Significant differences were found among host age groups.