ALENCE OF RUMINANT PESTIVIRUS INFECTIONS IN NAMIBIA
DEPNER, K., HUBSCHLE, O . J. B. & L1ESS, B. , 1991. Prevalence of ruminant pestivirus infections in Namibia. Onderslepoorl Journal ofVelerinary Research 58. 107-109 (1991) Following several clinical cases of suspected bovine virus diarrhoea .(BVD) on three Namibian ca ttle farms, a serological survey was cooducted on bovloe , ovme , capnne and wold rUffilOant sera originating from different regions of the country. Neutralizing antibodies to BVD ViruS (BVDV) were detected in 58 % of 1 014 cattle sera, 14 % of 618 sheep sera and 4,6 % of 1 118 goat sera. Sera from seven of teo wildlife species lVere positive with kudu , eland and giraffe having prevalence rates greater than 40 %. BVDV was isolated [rom six clinically affected bovlOes and three healthy heifers persistently infected with BVDV . The survey demonstrated that pestivirus infections are widespread 10 Namibia In hoth domestic and wild ruminants.
The prevalence of antibodies to bovine viral diarrhoea/mucosal disease virus in African wildlife.
Abstract A total of 3359 sera collected, between 1963 and 1978, from 45 different species of wildlife in nine African countries were examined for serum neutralising antibodies to bovine viral diarrhoea/mucosal disease virus. Titres significant of infection were recorded in 17 species including 10 not previously reported as sero-positive. Results indicate that infection is widespread and has been present for a considerable time. The prevalence and range of titres recorded suggest that some free-living species may be reservoirs of infection in the wild.
Spatial distribution of root lesion nematodes (Pratylenchus spp.) in a long-term no-till cropping system and their relationship with soil and landscape properties
The Cook Agronomy Farm of Washington State University is a long-term precision agriculture study site. Since 2000, the farm has been in various three-year no-till rotations with winter wheat, spring wheat, and various rotation crops such as barley, canola, peas, lentils, and chickpea. The spatial distribution of root lesion nematodes (Pratylenchus spp.) and their relationships with soil and terrain variables were studied by collecting soil samples at 127 and 124 geo-referenced points in two 12-ha fields during the spring of 2010 and 2011, respectively. Pratylenchus spp. were detected in more than 85% of the sampled locations in both fields. Nematode densities spatially mapped using ArcGIS software occurred in an aggregated pattern. Previous rotation crops had no effect on the spatial distribution. Classification and regression tree analysis (CART) using soil and terrain variables, and nematode density, explained 61 and 34% of the variability associated with nematode density in 2010 and 2011, respectively. Soil edaphic factors, such as organic matter, were stronger predictors of nematode populations than rotation effects.