A within farm clinical trial to compare two treatments (parenteral antibacterials and hoof trimming) for sheep lame with footrot

Abstract

with a prevalence of 10% lameness reported by farmers who treat lame sheep bytrimming 19 affected feet. We tested the hypothesis that prompt treatment of sheep lame with naturally 20 developing FR or ID with parenteral and topical antibacterials reduces the prevalence and 21 incidence of lameness with these conditions compared with less frequent treatment by trimming 22 hoof horn and applying topical antibacterials. A further hypothesis was that reduction of ID and 23 FR would improve productivity. A lowland sheep flock with 700 ewes was used to test these 24 hypotheses in an 18-month within farm clinical trial with four groups of ewes: two intervention 25 and two control. The duration and severity of lameness was used to categorise sheep into three 26 weighted scores of lameness (WLS): never lame (WLS0), lame for a maximum of six days with 27 locomotion score 2 (WLS1) and lame for more than six days or a higher locomotion score 28 (WLS2). The intervention reduced the prevalence of lameness due to FR and ID in ewes and 29 lambs and the incidence of lameness in ewes. The WLS was significantly lower in sheep in the 30 intervention groups. Ewes with a higher WLS were subsequently significantly more likely to 31 have a body condition score (BCS) <2.5 and have lame lambs. Significantly more ewes lambed 32 and successfully reared more lambs that were ready for slaughter at a younger age in the 33 intervention versus control groups. There was an increase in the gross margin of £630 / 100 ewes 34 mated in the intervention group, including the cost of treatment of £150 / 100 ewes mated. We 35 conclude that prompt parenteral and topical antibacterial treatment of sheep lame with ID and FR 36 reduced the prevalence and incidence of these infectious conditions and led to improved health, 37 welfare and productivity. 38 -3 - Lameness is one of the greatest concerns for poor welfare in sheep (Goddard et al., 2006; 44 Fitzpatrick et al., 2006). It has been estimated to cost the UK industry £24 million / annum 45 (Nieuwhof and Bishop, 2005). More than 90% of farmers in the UK report lameness in their 46 sheep, with a farmer-estimated prevalence of 10% with more than 80% of lameness caused by 47 footrot (FR) and interdigital dermatitis (ID) (Grogono-Thomas and Johnston, 1997; Kaler and 48 Green, 2008a). In a study of 209 sheep farmers, those treating all sheep with FR with parenteral 49 antibacterials and foot sprays reported a significantly lower peak prevalence of FR of 2% 50 compared with the 9%reported by farmers who treated FR by paring the hoof horn and spraying 51 disinfectant on to the foot (Wassink et al., 2003). In addition, farmers who reported prompt 52 treatment of mildly lame sheep also reported a lower prevalence of lameness than those treating 53 groups of lame sheep (Kaler and Green, 2008). Further evidence for the benefits of parenteral 54 antibiotics comes from a prospective longitudinal study of 160 sheep on one farm where the 55 treatment of sheep with FR and ID with parenteral and topical antibacteria...

A longitudinal study of the role of Dichelobacter nodosus and Fusobacterium necrophorum load in initiation and severity of footrot in sheep

“…The study was done in September/October 2006 when environmental conditions (rainfall and temperature) were conducive for transmission of disease. The flock had had lame sheep with SFR for >20 years, with a prevalence of 6–8% lameness at any one time (Wassink et al , 2010a). During the current study 30.5% of sheep in the flock had ID and 4.7% of sheep had SFR.…”

Within-Flock Population Dynamics of Dichelobacter nodosus

“…Footrot, caused by Dichelobacter nodosus (1), causes 70–90% of lameness and costs the UK sheep industry £24–84 million per year (2, 3). There are two distinct clinical presentations of footrot, an inflammation of the interdigital skin [interdigital dermatitis (ID)] and separation of the hoof horn from the underlying tissue (severe footrot).…”

Dynamics and impact of footrot and climate on hoof horn length in 50 ewes from one farm over a period of 10 months

“…Lameness in sheep causes pain (Ley et al., 1989) and reduces productivity (Wassink et al., 2010b). Two previous studies from random samples of British farmers estimated that the prevalence of lameness in 1997 and 2004 was approximately 10% (Grogono-Thomas and Johnston, 1997; Kaler and Green, 2009).…”