Evidence-based medicine: quality and comparability of clinical trials investigating the efficacy of prostaglandin F(2α) for the treatment of bovine endometritis.

The objective of this study was to evaluate the quality and comparability of published literature, and to summarize the effect of prostaglandin F(2α) (PGF(2α)) for the treatment of endometritis. It has been postulated that there is a dearth of high-level evidence-based research results in veterinary medicine. Also, there is a marked variation in the quality of studies in veterinary and animal science. Post-partum uterine infections occur commonly in dairy cattle and are reported to have a negative impact on reproductive performance. A comprehensive literature search was conducted utilizing online databases revealing a total of 2723 references. After applying specific exclusion criteria, a total of 68 trials were eligible for further analysis. These articles were evaluated utilizing specific parameters listed in an evaluation form such as randomization and the involvement of control groups. The analysis revealed that more than half of the trials (51·5%) were at least 20 years old. Furthermore, we found that about one third (36·8%) of all trials were controlled and randomized, while 3 of those (4·4%) were also blinded. Of those trials which calculated a calving-to-conception interval (n=30), 50% of the authors claimed an improvement, which was statistically significant in 23·3% of the cases. We conclude that there is a wide discrepancy between research results investigating the efficacy of PGF(2α).

Effects of mild mitral valve insufficiency, sodium intake, and place of blood sampling on the renin-angiotensin system in dogs.

In 23 Cavalier King Charles Spaniels, 12 with mild mitral valve insufficiency (MVI) and 11 controls, the activity of the renin-angiotensin system (RAS) was assessed by measuring the plasma renin activity (PRA) and plasma aldosterone concentration (PAC) in 5 different settings. The dogs were sampled at the clinic before the trial and thereafter at home and at the clinic; during both a period on control diet and a period on low sodium diet. The dogs with mild MVI had the highest median PRA and PAC in all 5 settings. An analysis of variance accordingly showed that dogs with mild MVI had significantly higher PRA (p < 0.0001) and PAC (p = 0.03) than controls, and that the sodium intake and place of blood sampling did not significantly affect this finding. The sodium intake had highly significant effects on PRA and PAC, and the place of blood sampling had no significant effects on PRA and PAC. The activity of angiotensin-converting enzyme in serum was lower in dogs with mild MVI than in controls (p = 0.0002). The plasma levels of endothelin-1, atrial natriuretic peptide, and arginine vasopressin, 3 peptides of pathophysiologic importance in congestive heart failure, were not significantly changed by the disease. The early activation of the RAS in dogs with MVI suggests that the valvular disease process itself might be the cause of the activation, but confirmation of this requires further studies.