Footbathing, formalin and foot trimming: The 3Fs associated with granulomas and shelly hoof in sheep.

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 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.

Short communication: Preliminary investigation into the effect of freezing and a cryopreservant on the recovery of mastitis pathogens from ewe milk.

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

Effects of systemic 3-nitropropionic acid-induced lesions of the dorsal striatum on cannabinoid and mu-opioid receptor binding in the basal ganglia.

Systemic administration of 3-nitropropionic acid (3NPA) in experimental animals produces bilateral striatal lesions similar to those seen in Huntington's disease (HD) caudate and putamen. 3H[-CP55,940 binding to cannabinoid receptors in human basal ganglia nuclei has been shown to be highly susceptible to the earliest pathological changes in the HD brain. In this study, to assess further the suitability of 3NPA-induced striatal lesions as a model for HD neuropathology, we examined the effects of striatal lesions induced by the systemic administration of 3NPA on the binding of 3H[-CP55,940 to pre- and postsynaptic cannabinoid receptors in striatum, globus pallidus, entopeduncular nucleus and substantia nigra pars reticulata and also the effect of 3NPA-induced striatal lesions on the binding of 3H[-DAMGO to mu-opioid receptors in striatal striosomes. Systemic administration of 3NPA induced bilateral and symmetrical lesions in dorsolateral striatum. Within the lesion core, 3H[-CP55,940 and 3H[-DAMGO binding density was reduced to background levels. Beyond the immediate borders of the central core of the 3NPA-induced lesion, striatal binding density was not significantly different from that measured in unlesioned rats. 3H[-CP55,940 binding in globus pallidus, entopeduncular nucleus and substantia nigra in 3NPA-lesioned rats was significantly reduced compared to controls, and the individual decreases were similar for each site. However, these reductions were statistically marginal. These data suggest that, while producing striatal lesions which bear some similarity to those seen in HD, the consequences of 3NPA for striatopallidal and striatonigral efferent projections do not reflect the reported neurodegenerative changes seen in the HD brain.