Granulomas and shelly hoof (SH), are lesions of sheep feet. Our objective was to use data from four questionnaires on lameness sent to English sheep farmers in 2004, 2013, 2014 and 2015 to further understanding of the risks and aetiologies of both lesions. Granulomas were more likely in flocks where routine foot trimming (odds ratio [OR] = 3.17; 95% confidence intervals [CI] 1.11-11.47) and routine footbathing (OR = 2.38; 95% CI 1.19-4.83) were practised than where these management protocols were not. SH was more likely in flocks that were footbathed in formalin compared with not footbathing (OR = 1.65; 95% CI 1.19-2.30), and was less common in flocks that stocked ewes at more than eight vs. four per acre (OR = 0.34; 95% CI 0.17-0.68). There were weak associations between SH and foot trimming. In 2004 only, SH was more likely in flocks where therapeutic foot trimming was practised than not practised (OR = 2.24; 95% CI 1.12-4.68). In 2014 33 only, SH was marginally less likely in flocks where no feet bled during trimming, compared with flocks not routinely trimmed (OR = 0.55; CI 0.30-1.00); SH was not related to foot trimming once severe footrot was included. We propose that flocks with granulomas and SH would decrease if farmers stopped footbathing in general, in particular with formalin, and avoided foot trimming whether as a therapeutic or routine practice. Further work is needed to understand the role of stocking density.

We present the largest and most representative study of the serological diversity of Dichelobacter nodosus in England. D. nodosus causes footrot and is one of the top five globally important diseases of sheep. The commercial vaccine, containing nine serogroups, has low efficacy compared with bivalent vaccines. Our aim was to investigate the prevalence and distribution of serogroups of D. nodosus in England to elucidate whether a bivalent vaccine could protect the national flock. Farmers from 164 flocks submitted eight interdigital swabs from eight, preferably diseased, sheep. All serogroups, A–I, were detected by PCR in 687/1150 D. nodosus positive swabs, with a prevalence of 2.6–69.3% of positive swabs per serogroup. There was a median of two serogroups per flock (range 0–6). Serogroups were randomly distributed between, but clustered within, flocks, with 50 combinations of serogroups across flocks. H and B were the most prevalent serogroups, present in > 60% of flocks separately but in only 27% flocks together. Consequently, a bivalent vaccine targeting these two serogroups would protect 27% of flocks fully (if only H and B present) and partially, if more serogroups were present in the flock. We conclude that one bivalent vaccine would not protect the national flock against footrot and, with 50 combinations of serogroups in flocks, flock-specific vaccines are necessary.

The objective of this study was to investigate the recovery of bacteria from ewe milk after freezing 28 for 4 or 8 weeks with and without the addition of glycerol as a cryopreservant. A total of 50 udder-29 half milk samples with a known range of bacterial species were selected, stored and analyzed in 5 30 treatment-groups: time zero, frozen for 4 weeks with, and without, glycerol; and frozen for 8 weeks 31with, and without, glycerol. There was a lower recovery of all bacterial species studied after 32 freezing. Samples containing fewer than 100 cfu/mL came from ewes with a lower somatic cell 33 count and were more likely to be bacteriologically negative after freezing than those above this 34threshold. The addition of glycerol increased recovery of Gram-negative bacteria after freezing, 35 although this requires further study to draw strong conclusions. The effects on Gram-positive 36 species were inconsistent. We conclude that whilst the addition of glycerol had a small beneficial 37 impact on the sensitivity of detection of bacteria from frozen sheep milk, sensitivity was highest in 38 cultures from fresh milk. 39 40

HighlightsInvestigate the role of D. nodosus and F. necrophorum in the progression of ovine FR.Markovian model developed using bacterial load and disease severity.The model generates probabilistic forecasts one week ahead.All 34 rates between the 12 states of an individual foot are time homogeneous.Results suggest primary role of D. nodosus in the initiation and progression of footrot.Results suggest a secondary role of F. necrophorum only in severely diseased feet.