The effect of the combined use of a long-acting antibiotic with NSAID on the clinical status and cellular immune response in calves affected with bovine respiratory disease

摘要

The aim of the study was to evaluate the effect of a combined use of a long-acting antibiotic with a nonsteroidal anti-inflammatory drug (NSAID) as an adjunctive therapy in calves suffering from bovine respiratory disease (BRD) on their clinical status and alterations of cellular immune indices in comparison with the antibiotic alone. The calves were treated either with a new combined antibacterial therapeutic agent (Resflor; MSD Animal Health, Boxmeer, Netherlands) consisting of both an antibiotic (florfenicol) and a NSAID (flunixin meglumine) in group I and antibiotic only (florfenicol) in the control group (group II). During the experiment the following parameters were measured: calf clinical status as so-called Clinical Illness Index Score (CMS)together with selected cellular immune parameters i.e. white blood cell count (WBC), number and percentage of polymorphonuclear leukocytes (PMNL), mid-size leukocytes (MID), monocytes (CD14+/CD45+) and total peripheral lymphocytes (LYM). The lymphocytepopulation was also subdivided into their subsets: CD2+ (T-lymphocytes), CD4+ (Th-lymhocytes), CD8+ (Tc/s-lymphocytes) and WC4+ (B-lymphocytes). The results obtained showed that the mean values of the WBC, PMNL, MID and monocytes decreased markedly in the both groups of calves after treatment. However, in the same animals the total number of lymphocytes and their subpopulations (CD2+, CD4+, CD8+, WC4+ cells) increased as a consequence of the treatment. In calves from group I most of the immune changes were statistically significant (p<0.05) compared with the control group or their initial values, which was indicated by a more rapid normalisation of the physiological ranges. In the same group of calves the more rapid recovery process which was observedwas manifested by the lower values of CMS. The study showed that the therapy based on using a new combined therapeutic agent (Resflor) was more effective and had a more protective effect in the calves affected with BRD both with regard to the improvementof their clinical status as well as the intensity and normalisation of the cellular immune response compared with the animals treated with the antibiotic alone.