Research Article Efficacy of Sulphachloropyrazine, Amprolium Hydrochloride, Trimethoprim-Sulphamethoxazole, and Diclazuril against Experimental and Natural Rabbit Coccidiosis Kennedy O. Ogolla , 1 Peter K. Gathumbi, 1 Robert M. Waruiru, 1 Paul O. Okumu, 1 Joyce Chebet, 1 and Philip M. Kitala 2 1 Department of Veterinary Pathology, Microbiology and Parasitology, University of Nairobi, P.O. Box 29053-00625, Kangemi, Nairobi, Kenya 2 Department of Public Health, Pharmacology and Toxicology, University of Nairobi, P.O. Box 29053-00625, Kangemi, Nairobi, Kenya Correspondence should be addressed to Kennedy O. Ogolla; kokothogola2008@gmail.com Received 6 May 2018; Accepted 15 October 2018; Published 23 October 2018 Academic Editor: William Alberto Ca˜ n´ on-Franco Copyright © 2018 Kennedy O. Ogolla et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Tere are no anticoccidial drugs labelled for rabbits in Kenya and those available are used as extra labels from poultry. Te drugs are used in rabbits with limited knowledge of their efcacy and safety. Te aim of this study was to determine the efcacy of sulphachloropyrazine, amprolium hydrochloride, and trimethoprim-sulphamethoxazole relative to diclazuril when used curatively against experimental and natural rabbit coccidiosis. In a controlled laboratory trial, sixty (60) rabbits were randomly allocated to six treatment groups, namely, 1A, 2B, 3C, 4D, 5E, and 6F, each with 10 rabbits. Groups 2B, 3C, 4D, 5E, and 6F were experimentally infected with mixed Eimeria species while group 1A served as uninfected-untreated (negative) control group. Four of the infected groups were treated with sulphachloropyrazine (5E), amprolium hydrochloride (2B), trimethoprim-sulphamethoxazole (6F), and diclazuril (4D) using dosages recommended by manufacturers. Group 3C served as infected-untreated (positive) control. A feld efcacy trial in naturally infected rabbits was then undertaken. Te results revealed that sulphachloropyrazine and diclazuril were efective against rabbit clinical coccidiosis by signifcantly reducing oocyst counts from 149.00±110.39 x 10 4 to 3.31±0.86 x 10 4 Eimeria spp. oocysts per gram of feces (opg) and 59.70±12.35 x 10 4 to 0.0±0.0 x 10 4 opg, respectively, in the laboratory trial. Similarly, sulphachloropyrazine and diclazuril recorded reduced oocyst counts in the feld trial from 280.33±44.67 x 10 3 to 0.44±0.14 x 10 3 opg and 473.44±176.01 x 10 3 to 0.0±0.0 x 10 3 opg, respectively. Still, sulphachloropyrazine and diclazuril showed superior efcacy by registering lesion scores and fecal scores close to those of uninfected untreated control group. Trimethoprim-sulphamethoxazole recorded a satisfactory efcacy in the feld trial by recording reduced oocyst counts from 266.78±37.03 x 10 3 to 0.75±0.11 x 10 3 opg but was not efcacious in the laboratory trial. Amprolium hydrochloride was not efcacious against clinical coccidiosis in both the experimental and feld trials. 1. Introduction Te most notable of rabbit diseases is coccidiosis which causes massive economic losses in rabbit production [1, 2]. Coccidiosis results in high mortality and morbidity especially among weaner rabbits [2]. Tirteen Eimeria species with varied pathogenicity are known to cause coccidiosis in rabbits [1]. Two forms of coccidiosis exist in rabbits (Oryctolagus cuniculus): intestinal coccidiosis where the invading proto- zoan target epithelial cells of diferent regions of the intestines resulting in moderate to severe damage depending on the virulence of the species [3] and hepatic coccidiosis where the predilection site of E. stiedae is the liver [2, 4]. Tough most hepatic infections are mild, severe cases can result in Hindawi Journal of Veterinary Medicine Volume 2018, Article ID 5402469, 11 pages https://doi.org/10.1155/2018/5402469