Table 2.

Large bowel diarrhoea protocol

Weeks 1–2	Faecal float Faecal Gram stain Faecal wet mount Faecal Giardia SNAP test If faecal tests negative: Fenbendazole 50 mg/kg (22.7 mg/lb) orally daily for 5 days (Barr et al. 1994; Plumb 2018) Commence high fibre diet dietary trial (Lecoindre & Gaschen 2011) If faecal float positive: Roundworm or hookworm Fenbendazole [50 mg/kg (22.7 mg/lb) orally daily], one 3‐day course (Plumb 2018) Whipworm Fenbendazole three 3‐day course [50 mg/kg (22.7 mg/lb) orally daily], immediately, then again at 3 weeks and 3 months (Plumb 2018) Coccidia Sulphadimethoxine 55 mg/kg (25 mg/lb) 1st day, then 27.5 mg/kg (12.5 mg/lb) daily for 9 days (Plumb 2018) Spirometra Praziquantel at label dosage (Plumb 2018) Plus appropriate environmental control as needed Then repeat float 10–14 days later If faecal Gram stain positive: Clostridium (over 15 organisms/high power field), give metronidazole 10–15 mg/kg (5.5–6.8 mg/lb) orally twice daily for 5 days (Plumb 2018) If wet mount or Giardia SNAP positive: Give metronidazole 30 mg/kg (13.6 mg/lb) orally twice daily for 3–5 days (Reddy et al. 1992)
Week 3 (if diarrhoea persists)	Commence limited antigen dietary trial (Zoran 2003; Mandigers et al. 2010; Westermarck 2016) Commence concurrent fibre (Lecoindre & Gaschen 2011) Psyllium; ½ tablespoon daily toy breed, 1 tablespoon daily small breed, 2 tablespoons daily medium breed, 3 tablespoons daily large breed Commence probiotic trial (Sauter et al. 2006; Rossi et al. 2014; Schmitz et al. 2015a,b) If faecal tests positive for organisms Weeks 1–2, and treated, repeat test: Consider alternate therapies if still positive
Week 4 (if diarrhoea persists)	Continue current diet and concurrent fibre trials Change probiotic (Sauter et al. 2006; Rossi et al. 2014; Schmitz et al. 2015a,b)
Week 5 (if diarrhoea persists)	Continue current diet and concurrent fibre trials Commence antibiotic trial (Kilpinen et al. 2015) Tylosin 25 mg/kg (11.4 mg/lb) orally once daily for 7–14 days (Kilpinen et al. 2015)
Week 6 (if diarrhoea persists)	Continue current diet and concurrent fibre trials Rectal scrape (Wilson et al. 2018) Faecal transplant (Chaitman et al. 2016; Bottero et al. 2017) If not improved by end of week 6, commence specialist‐level investigation
Selected scenarios	Young Boxers, English bulldogs, French bulldogs that have failed initial standard large bowel diarrhoea protocol: Enrofloxacin 5–10 mg/kg (2.3–4,6 mg/lb) once daily 6 weeks (Hostutler et al. 2004; Craven et al. 2011)

Protocol is not intended to be rigidly adhered to and flexible modifications are recommended based on individual patient circumstances.