Watery Mouth Disease prevalence in lambs treated with MonoShield vs Spectam
Background
During the 2022 lambing season, an opportunity arose to compare the clinical treatment data on farms using the feed supplement MonoShield™ versus spectinomycin (Spectam) on farms which had a limited supply of Spectam in stock from the previous year. This was overseen by the vet for the flocks.
Trial
Three farms supplied clinical treatment information for retrospective efficacy analysis. All three lambed lowland ewes indoors between January and April. Two farms were located in Devon and the third in Lanarkshire. Ewe breeds included Texel x Lleyn, Lacaune, Highlander, Primera and Poll Dorset. A total of 1,734 lambs data was available, lambs were sired by Texel, Charolais, Abermax, Aberfield, Lacaune and Primera rams. All three farms had used Spectam as a prophylaxis for all lambs for many years. Each farm had a limited stock of unused Spectam available from the previous year but insufficient doses for all lambs anticipated based upon the ultrasound pregnancy detection data for the 2022 lambing season.
MonoShield™ was prescribed by the vet for each farm for all the remaining lambs. Allocation of lambs for either Spectam or MonoShield™ was based on the technical skill and ability of the shepherds on the farm. In each case the most experienced member of staff administered the MonoShield™ tablet to lambs born during their lambing shift and all other staff administered Spectam drench. Both treatments were administered throughout the entire lambing period. All three farms declared that they had similar policies for colostrum administration, summarised as follows:
- Lambs allowed to suck colostrum on their own in individual lambing pens.
- Lambs not observed suckling are fed 50-60ml of colostrum collected from their dam by feeding tube or, from another recently lambed ewe with a single lamb or, (in 1 farm only) from a store of frozen ewe colostrum. One farm also used artificial powdered colostrum (Volostrum) for a small number of lambs meeting these criteria at the start and end of lambing but not during the peak lambing periods.
- Small lambs and weak lambs were given additional colostrum or milk feeds in the period in the individual pens.
- Spectam and MonoShield™ were administered as early as possible, in some cases it is likely that these were administered before much or any colostrum has been consumed, in other cases the treatment is likely to have been administered after colostrum has been consumed.
- None of the farms recorded which lambs had received colostrum by feeding tube.
The prevalence of WMD was low on all three farms. The prevalence observed in 2022 was similar to that experienced in previous years in each farm. The results for the three farms are displayed in Table 1.
The lambs given MonoShield™ had an average Watery Mouth prevalence across the three flocks of 1.1% versus 1.4% for the lambs given Spectam.
