Evaluation of Orally Administered Anthelmintic Treatment Options for Dentostomella translucida in Naturally Infected Mongolian Gerbils (Meriones unguiculatus)

Objective: This study aimed to evaluate the efficacy of eprinomectin, moxidectin and fenbendazole for treating Dentostomella translucida infections in naturally infected Mongolian gerbils (Meriones unguiculatus). Methods: A total of 28 gerbils were placed in individually numbered cages to determine the individual animal parasite load. Eggs per gram (EPG) counts were used to estimate the efficacy of the drugs. The day before the anthelmintic administration was denoted as day 0, and the EPG counts were determined by the McMaster technique from the stool removed from the cage bottom on days 7, 14, 21 and 28. The animals were assigned to one of four treatment groups according to their day 0 EPG counts. The orally administered drugs in the treatment groups were eprinomectin (15 mg/kg), moxidectin (0.4 mg/kg) and fenbendazole (12 mg/kg) for groups 1-3, respectively. The fourth group served as the control (without any drug administration). Results: Treatment efficacy was evaluated based on weekly EPG counts. The values decreased to zero in the fenbendazole group at 4 weeks of follow-up after treatment, and no parasite was found in any of the repeated examinations. The eprinomectin and moxidectin groups exhibited a fluctuating EPG state on both individual and group basis. Conclusion: D. translucida, which is known as the specific parasite of gerbils, can easily affect other members of the animal colony; thus, the control of its presence in gerbil breeding units is necessary. Therefore, the reported effective drug treatments are important for the fight against the investigated parasitic infection.

The efficacy of ivermectin against the eyeworm, Thelazia skrjabini, in experimentally infected cattle.

The anthelmintic efficacy of ivermectin (administered subcutaneously at 200 micrograms kg-1 body weight) was assessed for control of Thelazia skrjabini in experimentally infected calves. Twenty-four uninfected male Holstein calves, 1-2 weeks old, were artificially infected with Thelazia skrjabini by placing 15 third-stage larvae under the third eyelid of calves. The challenge larvae were recovered from naturally infected face flies, Musca autumnalis. The exposed calves were randomly assigned to either an ivermectin treatment group or a control group within pairs ranked by weight. Equal numbers of calves were housed in each of four indoor fly-free rooms. The calves were treated with ivermectin or saline 35 days post-infection, then slaughtered 14 days later to determine eyeworm numbers. All eyes and associated tissues (including the lacrimal glands and ducts) were removed and examined for total number, species and viability of eyeworms. Thelazia skrjabini was found in the control group of calves only. The efficacy of ivermectin against Thelazia skrjabini was thus shown to be 100%.