Clinical and Parasitological Evaluation of Ivermectin and Ivermectin + Pyrantel Against Oxyuris Equi in Equines.

The equine pinworm could become an increasingly common problem, as there are reports of failure in the control of this parasite. The aim of this study was to evaluate the effects of ivermectin (IVM) and IVM combined with pyrantel pamoate (PYR). Thirteen parasitological positive equines were treated with oral IVM (200 µg/kg) and therapeutic efficacy, clinical recovery and the egg reappearance period (ERP) were evaluated. In cases for which ERP was shorter than the pre-patent period (PPP), a second treatment was performed with IVM (200 µg/kg) + PYR (6.6 mg/kg), followed by the same evaluation criteria described above. Therapeutic efficacy was 100% with IVM + PYR and 53.84% with IVM. The mean ERP was shorter than the PPP with both formulations, 77.55 days with IVM + PYR and 50 days with IVM. The presence of egg mass was always associated with a least one clinical sign. The reduction in the number of clinical signs per animal from Day 0 to Day 30 was greater in equines treated with IVM + PYR compared to those treated with IVM alone. The animals treated with IVM were 4.5-fold more likely to present clinical signs 30 days after treatment than those treated with IVM+PYR. A negative correlation was found between ERP and the number of clinical signs at 30 days in the animals treated with IVM. This clinical and parasitological evaluation demonstrated that the combination of IVM+PYR was more effective than IVM alone to control Oxyuris equi.

Molecular and phenotypic characterization of Escherichia coli from calves in an important meat-producing region in Brazil.

INTRODUCTION: Escherichia coli strains that lead to enteritis are considered an important cause of diarrhea in calves. For correct identification, these microorganisms must be differentiated from non-pathogenic members of the intestinal microbiota. The aim of the present work was to characterize E. coli isolates in calves regarding the presence of virulence genes that cause enteritis and evaluate the sensitivity of the isolates to different antimicrobials. METHODOLOGY: One hundred forty-nine samples from beef cattle and 27 samples from dairy cattle were evaluated. All samples were submitted to microbiological identification and the disk diffusion antibiogram test. The polymerase chain reaction method was used to detect virulence genes. RESULTS: A hundred seventy-six samples were biochemically identified as E. coli and antibiograms were determined. The samples were then submitted to PCR; 35 were positive for the eae gene (19.88%), 135 (76.70%) for the stx1 gene, 62 (35.22%) for the stx2 gene, 159 (90.34%) for the sta gene and 35 (19.88%) for the ltII gene. No samples were positive for the cnf gene. Based on these results, the E. coli isolates were classified into pathotypes: enteropathogenic (n = 3), enterohemorrhagic (n = 32), Shiga toxin-producing (n = 122) and enterotoxigenic (n = 163). The antimicrobial sensitivity tests revealed that 77.2% of the isolates were resistant to three or more pharmacological groups, characterizing these isolates as multidrug resistant. CONCLUSIONS: Enterotoxigenic E. coli was the predominant pathotype. Moreover, the prevalence of multidrug-resistant isolates was very high, accounting for the vast majority of isolates.