A survey of horses with acute diarrhoea: diagnosis, assessment of the prognosis, and comparison of two antibiotic therapies.

This research article delves into a study that explored the diagnosis, prognosis, and comparison of two antibiotic therapies for horses suffering from acute diarrhea. The study concluded it was difficult to predict the prognosis of an individual patient via single or multiple variables, and found no significant difference between the two antibiotic treatment groups.

Study Design and Methodology

In the study, twenty horses, ponies and foals suffering from acute diarrhoea were randomly assigned to two treatment groups. These animals were divided in the following manner:

• One group treated with trimethoprim/sulfadiazine via intravenous means.
• The other group treated with ampicillin/gentamicin.

Both groups received identical standardized symptomatic therapy. The clinical evaluation of all animals was conducted on the basis of five variables: general impression, heart rate, rectal temperature, appetite, and consistency of the faeces. These variables were rated on a five-point scale.

Sampling and Analysis

The researchers took jugular blood samples at admission and continued this at regular intervals for standard screening. Additional attributes like the packed cell volume, white blood cell count, and base excess were classified on the same five-point scale. Here, a ‘diarrhoea prognosis index’ was calculated, which was the sum of all eight scaled variables.

Data Outcome

Faecal samples were cultivated aerobically and examined for worm eggs and larvae. A definitive diagnosis was made for only 55% of the horses—11 out of 20. The most frequent cause of diarrhoea was found to be salmonellosis followed by parasitic infections. However, a significant 35% of the horses (three from the ampicillin/gentamicin group and four from the trimethoprim/sulfadiazine group), were euthanized or died due to the grim prognosis.

Findings and Conclusion

Upon comparison of the horses that survived against those that didn’t, only the packed cell volume illustrated any notable differences. However, neither single nor a combination of clinical or haematological/biochemical variables could accurately predict the prognosis for an individual patient. The researchers concluded that the clinical reaction to treatment within 4 days was the only reliable indication for the outcome of an individual horse. Further, the study found no significant difference between the clinical outcomes of both antibiotic treatment groups. This suggests that it’s challenging to reach a specific diagnosis in horses with diarrhoea and no single treatment methodology or variables offer a better prognosis over the other.