Retrospective evaluation of the patterns of clinical use of anti-parasitic agents on animals presented for veterinary care at an animal hospital in Nigeria

Abstract

Patterns of use of anti-parasitic agents (APAs) on animals presented for veterinary care at the Veterinary Teaching
Hospital, Nsukka, Nigeria, from January 2013 to December 2017 were surveyed. Animals presented were
predominantly dogs (84.0%) and goats (8.1%). A total of 4851 cases were evaluated, out of which 3196 (65.9%) were
treated with APAs. There was a significant variation (p=0.002) in the annual frequency of use of APAs across the study
period, but the effect size of the variation was small (ɸc=0.06). Ivermectin was the most frequently used APA (1479 out
of the 3196 = 46.3%); followed by praziquantel-pyrantel-fenbendazole combined formulation (PPFCF) (1231 out of the
3196 = 38.5%), pyrantel pamoate (848 out of the 3196 = 26.5%) and benzimidazoles (477 out of the 3196 = 14.9%). The
frequencies of use of others were below 10%. There were significant variations (p<0.01) in the frequency of use of all
the APAs across the study period, but the effect size of the variations ranged from small for amitraz (ɸc=0.08; p=0.001),
amprolium-sulphaquinoxaline combination (ASC) [ɸc=0.07; p=0.006] and fipronil (ɸc=0.09; p=0.000), to moderate for
benzimidazoles (ɸc=0.12; p=0.000), diminazene aceturate (ɸc=0.11; p=0.000), ivermectin (ɸc=0.11; p=0.000) and pyrantel
pamoate (ɸc=0.10; p=0.000), and large for cypermethrin (ɸc=0.15; p=0.000), levamisole (ɸc=0.15; p=0.000), metronidazole
(ɸc=0.24; p=0.000), PPCFC (ɸc=0.18; p=0.000) and pyrethrin powder (ɸc=0.27; p=0.000). Out of the 3196 cases in which
APAs were used, there were inappropriate use in 8.9% of cases, non-compliance in 44.0%, use of APAs without
definitive diagnosis in 46.8%, and wrong combinations in 8.8%. The frequencies of misuse of the APAs varied
significantly (p=0.000) across the study period, and the effect size was moderate for inappropriate use (ɸc=0.13;
p=0.000), non-compliance (ɸc=0.14; p=0.000) and wrong combinations (ɸc=0.10; p=0.000), but large for the use of APAs
without definitive diagnosis (ɸc=0.23; p=0.000). It was concluded that the overall frequency of use of APAs in the study
population was high during the study period, with significant variations in the frequency and effect size of the specific
APAs, and their misuse.