In this study, daily supplementation with psyllium husk improved clinical signs in police working dogs with chronic diarrhoea, decreasing defecation frequency and improving stool consistency. Treated animals also exhibited a weight gain. These beneficial effects were still felt in the second month of monitoring without psyllium supplementation for most animals.
In a previous study regarding the management of chronic large-bowel diarrhoea laboratory results are usually normal, with only mild abnormalities identified in 37.8% of cases: high ALP, a slight increase in ALT, slight hypoalbuminemia, lymphocytosis, eosinophilia, lymphopenia, and slight neutropenia . Other reports point out that working dogs, in particular, typically have higher values of ALP, which, together with lipase, can help determine the presence of pancreatitis in dogs [16,17,18,19]. A lack of recovery and the chronicity of the condition is frequently associated with anaemia and severe hypoalbuminemia . Our results are in line with these reports, as no abnormalities were observed during the physical examination, and CBC scores and serum biochemistry were also normal.
Various personality traits and stressful factors have been described and associated with chronic large-bowel diarrhoea in dogs. Dogs with chronic large-bowel diarrhoea have been described as nervous and high-strung, accounting for 37.8% of cases in a review study . This high-strung characteristic can describe all of the dogs included in this study. In addition to breed-specific traits, such as the case of Belgian Malinois, these dogs present very high drives besides being very active when kennelled. A stressful event often initiates clinical signs, a phenomenon often observed in working dogs [2, 6], in contrast to what is observed in sedentary dogs, where exercise can help with chronic diarrhoea . Training and active work are sources of multiple events that can induce stress, thus providing various opportunities to trigger clinical signs. Besides, exercise can also offset a phenomenon similar to runner’s diarrhoea in humans. Decreasing kennel stress and better preparing working animals from a very young age to cope with stress is warranted and may help reduce this problem. Preparing future working dogs for predictable challenges from a very young age has recently been a topic of interest [21, 22]. It may set the stage for study work analysing its effect on this type of diarrhoea.
Adding fiber, and consequently, short-chain fatty acids can help to protect from colitis . It may be an interesting supplementation to regularly maintain working dogs due to their proneness to develop colitis. Still, some difficulties may arise when administering it to dogs. The psyllium presentation used in this study was a powder, and the amount administered to large dogs may decrease appetence and overall palatability. Some cases may also require medication introduction, such as antibiotics (oxytetracycline, metronidazole, or tylosin) . Metronidazole, in particular, is also effective in reducing chronic intestinal inflammation and colitis . No medication was used for any of the dogs enrolled. Probiotics have also been suggested for human athletes, as they can colonize the gastrointestinal tract, adding benefits to health in general, as changes in immune and inflammatory markers in humans . This approach may be of interest to working dogs, so further studies are required to test this possibility.
This study presents some limitations, namely its sample size, the lack of a control group, and the fact that it was not double-blinded. Since the present study showed positive results in managing chronic large-bowel diarrhoea, future studies should enroll a larger number of animals and a control group.