Farming on the edge: farmer attitudes to bovine tuberculosis in newly endemic areas.

Defra's recent strategy to eradicate bovine tuberculosis (bTB) establishes three spatial zones: high-risk areas (HRAs) and low-risk areas, and an area referred to as 'the edge', which marks the areas where infection is spreading outwards from the HRA. Little is known about farmers in the edge area, their attitudes towards bTB and their farming practices. This paper examines farmers' practices and attitudes towards bTB in standardised epidemiologically defined areas. A survey was developed to collect data on farmer attitudes, behaviours, practices and environmental conditions as part of an interdisciplinary analysis of bTB risk factors. Survey items were developed from a literature review and focus groups with vets and farmers in different locations within the edge area. A case-control sampling framework was adopted with farms sampled from areas identified as recently endemic for bTB. 347 farmers participated in the survey including 117 with bTB, representing a 70per cent response rate. Results show that farmers believe they are unable to do anything about bTB but are keen for the government intervention to help control the spread of bTB.

Endothelin(A) (ET(A)) and ET(B) receptor-mediated regulation of nitric oxide synthase 1 (NOS1) and NOS3 isoforms in the renal inner medulla.

AIM: Our laboratory and others have shown that endothelin (ET)-1 directly stimulates nitric oxide (NO) production in inner medullary collecting duct (IMCD) cells. The goal of this study was to determine which NO synthase (NOS) isoforms in IMCD are sensitive to ET-1, and the role of ET(A) and ET(B) receptor activation in vivo and in vitro. METHODS: NOS enzymatic activity and NOS isoform protein expression were examined in cultured IMCD-3 cells and isolated renal inner medulla. ET(B) receptor-deficient homozygous rats (sl/sl) have elevated levels of circulating ET-1 and lack a functional ET(B) signalling pathway in kidneys, and furthermore provides a unique model to study ET(A) receptor signalling in the renal inner medulla in vivo. RESULTS: Incubation of IMCD-3 cells with exogenous ET-1 (50 nm) resulted in ET(A)-dependent increased NOS1 protein expression in IMCD-3 cells with no effect on NOS2 or NOS3 expression. ET(B) receptor antagonism has no effect on NOS expression in IMCD-3 cells. Consistent with in vitro results, cytosolic NOS1 protein expression was significantly greater in the renal inner medulla of sl/sl rats compared with heterozygous (sl/+) controls, with no alteration in NOS3 expression. In contrast to protein expression data, NOS1- and NOS3-specific enzymatic activities decreased in the cytosolic fraction from the renal inner medulla of sl/sl compared with sl/+. CONCLUSION: These results provide evidence that both ET(A) and ET(B) receptors regulate NOS isoform activity in the renal inner medulla and specifically support the hypothesis that ET(A) receptor activation increases NOS1 expression.

No increase in human cases of Mycobacterium bovis disease despite resurgence of infections in cattle in the United Kingdom.

A resurgence of Mycobacterium bovis infections in cattle in the United Kingdom since the 1980s has raised concern about risks to human health. Enhanced surveillance data for England, Wales and Northern Ireland between 1993 and 2003 of culture-positive human M. bovis cases identified 315 M. bovis infections; the mean annual number of cases was 28 (range 12-41). The most frequently reported exposures were consumption of unpasteurized dairy products 41/83 (49%) and exposure to cattle 45/123 (37%). Of all cases, 249 (83%) were born before 1960. Of 50 cases born after 1960, only 14 were born in the United Kingdom. Over the same time period the annual number of new herd infections increased from 332 to 1749 as derived from the UK State Veterinary Service database. In conclusion, despite a more than fivefold increase in cattle herd infections during the 1990s, there was no increase in reported human cases.