A serological survey of ruminant livestock in Kazakhstan during post-Soviet transitions in farming and disease control.

The results of a serological survey of livestock in Kazakhstan, carried out in 1997--1998, are reported. Serum samples from 958 animals (cattle, sheep and goats) were tested for antibodies to foot and mouth disease (FMD), bluetongue (BT), epizootic haemorrhagic disease (EHD), rinderpest (RP) and peste des petits ruminants (PPR) viruses, and to Brucella spp. We also investigated the vaccination status of livestock and related this to changes in veterinary provision since independence in 1991. For the 2 diseases under official surveillance (FMD and brucellosis) our results were similar to official data, although we found significantly higher brucellosis levels in 2 districts and widespread ignorance about FMD vaccination status. The seroprevalence for BT virus was 23%, and seropositive animals were widespread suggesting endemicity, despite the disease not having being previously reported. We found a few seropositives for EHDV and PPRV, which may suggest that these diseases are also present in Kazakhstan. An hierarchical model showed that seroprevalence to FMD and BT viruses were clustered at the farm/village level, rather than at a larger spatial scale. This was unexpected for FMD, which is subject to vaccination policies which vary at the raion (county) level.

First evidence of bluetongue virus in Kazakhstan.

We report the results of the first serological survey for bluetongue virus in Kazakhstan. We analysed blood samples collected from 958 livestock and 513 wild saiga antelopes over a large area of the country, and found 23.2% seroprevalence in livestock and 0% in saigas. Seroprevalence in livestock did not vary by species, but increased significantly with age. There was no evidence for variation in seroprevalence at the regional level, but there was significant clustering at the farm level. Bluetongue has never before been reported in Kazakhstan, yet our results suggest that it may be endemic. We found seropositive animals at the furthest known northern limits of the bluetongue virus in this region of the world. Recorded vectors are not known to be present in Kazakhstan, so a novel vector is likely to be operating. The lack of evidence for bluetongue virus in saigas is unexpected and suggests a need for further investigation.

Prevalence and distribution of foot lesions in finishing pigs in south-west England.

This paper gives the first estimate of the prevalence and distribution of foot lesions in finishing pigs in the south-west of England for 33 years. It was based on the examination of 4038 finishing pigs from 21 units. There were 3727 out of 3974 (93.8 per cent) pigs with at least one foot lesion. The prevalence of different lesions was: toe erosion (33.0 per cent), sole erosion (62.1 per cent), heel erosion (13.0 per cent), heel flaps (14.4 per cent), white line lesions (55.4 per cent), false sand cracks (23.9 per cent) and wall separation (11.5 per cent). The hind feet were more commonly affected than the front feet, and on each foot the lateral digits were significantly more frequently affected than the medial digits. Sole erosions, heel flaps, wall separation and false sand cracks were more frequently observed on the lateral than the medial digit. Digits with sole erosions were significantly more likely to have heel flaps, white line lesions or false sand cracks than those without sole erosions. Furthermore, there was a within digit association between overgrown hooves and toe erosion. The effects of weightbearing, gait and environment on the development of foot lesions is discussed.