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Bovine tuberculosis (TB) is a significant threat to the cattle industry in England and Wales. It is widely acknowledged that a combination of measures targeting both cattle and wildlife will be required to eradicate bovine TB or reduce its prevalence until European official freedom status is achieved. Vaccination of cattle and/or badgers could contribute to bovine TB control in Great Britain, although there are significant gaps in our knowledge regarding the impact that vaccination would actually have on bovine TB incidence. Laboratory studies have demonstrated that vaccination with BCG can reduce the progression and severity of TB in both badgers and cattle. This is encouraging in terms of the prospect of a sustained vaccination programme achieving reductions in disease prevalence; however, developing vaccines for tackling the problem of bovine TB is challenging, time-consuming and resource-intensive, as this review article sets out to explain. [ABSTRACT FROM AUTHOR]

Drunken lamb syndrome (DLS) is a fatal disease of unknown aetiology affecting young lambs. In 2011, a prospective on farm cohort study was carried out to investigate the epidemiology and pathophysiology of DLS. Ten cases from a cohort of 1635 crossbred and pure Welsh Mountain lambs were identified as having DLS on the basis of characteristic clinical signs. Renal histopathology demonstrated nephrosis in all 10 cases. Some cases also demonstrated concurrent intestinal pathology. The cases were significantly smaller than the cohort, nine out of the 10 were twins, and they all demonstrated a severe metabolic acidosis characterised by elevated D-lactate. This study demonstrates that D-lactate--probably initiated by the overgrowth of intestinal microorganisms--appears to be the cause of the metabolic acidosis seen in cases of DLS, and to be responsible for the clinical signs seen. It is unclear as to the significance of the nephrosis lesions, and the name 'Lamb Nephrosis' may be misleading. Treatment may be possible using solutions of sodium bicarbonate [ABSTRACT FROM AUTHOR]

This study used adaptive conjoint analysis to quantify veterinary surgeons' and farmers' perceptions of a number of previously identified, viable mitigation strategies for controlling bluetongue. Data were collected using a questionnaire survey and face-to-face interviews. A total of 178 completed questionnaires were collected, 121 from farmers and 57 from veterinary surgeons. There were strong significant differences between the strength of preference of farmers and veterinary surgeons for a number of strategies. There was also large variation in the strength of preference among veterinary surgeons with respect to options involving vaccination. The results suggest uncertainty among both veterinary surgeons and farmers regarding the efficacy of current strategies, and suggest the need for dissemination of information to veterinary surgeons and farmers to be better coordinated. [ABSTRACT FROM AUTHOR]

Passive surveillance for European bat lyssaviruses (EBLV5) in the UK began in 1987, and between 1987 and 2004, 4883 bats of European origin (4871 belonging to 17 UK resident species and 12 belonging to seven non-UK resident species) were tested. The proportions and numbers of each species submitted from different regions varied considerably, partly owing to inherent biases in the passive surveillance, and there were seasonal variations in the numbers, sex and age of the bats. Contact with cats was reported in approximately 30 per cent of the bats submitted. Daubenton's bat (Myotis daubentonii) was the only species found to be positive for lyssavirus infection, with four cases of EBLV type 2 identified, in 1996, 2002, 2003 and 2004. No active infection with EBLV type 1 was recorded. [ABSTRACT FROM AUTHOR]

This paper estimates the financial incentive to control paratuberculosis on dairy farms by establishing the level of expenditure that would minimise the total cost of the disease (output losses plus control expenditure). Given the late onset of the clinical signs and the lack of treatments, control was focused on minimising the financial impact of paratuberculosis by adjusting the dairy cow replacement policy. The optimum replacement policies for disease-free herds and infected herds were compared by using dynamic programming. At the standard settings, the disease justified adjusting the culling policy; under constant bioeconomic assumptions, it reduced the expected annuity from milk production under the optimal replacement policy by about 10 per cent (£27 per cow annually), a considerably lower figure than for other major endemic diseases that affect dairy cows in the UK. The effect was even less at lower milk prices, suggesting that there is at present little incentive for dairy farmers to put more resources into controlling the disease. However, the incentive could be increased if more information were available about how best to manage the disease under specific farm circumstances. Any effect that paratuberculosis may have on the future demand for milk and hence on milk prices would also be an important consideration. [ABSTRACT FROM AUTHOR]

Five tests for antibodies against chiamydial (enzootic) abortion of ewes were compared using 255 sera from experimentally (group 1) or naturally (group 2) infected animals, flocks free of the disease (group 3) and individual animals testing positively by the complement fixation test but from flocks with no evidence of chlamydial abortion (group 4). Sera from five specific pathogen-free lambs vaccinated with two different subtypes of were also included (group 5). All tests used some form of processed culture of as antigen. Specificities, established with groups 3 and 4 sera, ranged between 96 per cent (ELISA using lipopolysaccharide antigen) and 59 per cent (Immunocomb). Reactions with group 5 sera suggested that the cause of false positive results in the field might be cross-reactive antibodies against the arthritogenic subtype of . Sensitivities, established with groups 1 and 2 sera, ranged bewteen 81 per cent (Immunocomb) and 51 per cent (ELISA using solubilised protein antigen). The minimum sample sizes required to be 95 per cent certain of detecting at least five seropositives in two infected flocks (combined data) were 15 to 48, dependent on the test applied. The Western blot test, applied to a proportion of samples, yielded no false positives with group 3 sera but 31P7 per cent with group 4 sera. Thus, none of the tests in this comparison emerged as sufficiently satisfactory in all respects, suggesting that further improvements in chlamydial serology must come through the use of non-native antigens or in the form of a competitive ELISA. [ABSTRACT FROM PUBLISHER]

Drunken lamb syndrome (DLS) has recently been described as lamb D-lactic acidosis syndrome (LDLAS). In 2012, 18 lambs aged between 7 days and 28 days with LDLAS were identified. Biochemically, each lamb had a metabolic acidosis characterised by D-lactic acidosis and exhibited clinical signs including: not hyperthermic, no evidence of dehydration, demonstrating an ataxic gait tending to recumbency (DLS) and possibly somnolence. These lambs received 50 mmol of sodium bicarbonate as an 8.4 per cent solution given orally, together with parenteral long-acting amoxicillin. All 18 cases made a full clinical recovery. This study demonstrates a novel effective treatment for a disease that is usually fatal, and also demonstrates a strong correlation between venous plasma bicarbonate concentrations and venous plasma D-lactate concentrations (R2=0.49). [ABSTRACT FROM AUTHOR]