The effect of self-licking behavior on pharmacokinetics of eprinomectin and clinical efficacy against Psoroptes cuniculi in topically administered rabbits

Abstract

Ear mange mite Psoroptes cuniculi, one of the predominant parasites in rabbits, can cause considerable weight loss, low favorable fee conversion rates, and meningitis. The present experiment was to investigate the difference of plasma disposition and the variation of clinical efficacy under the effect of animal self-licking behavior in topically administered rabbits. Ten rabbits for pharmacokinetic study in two groups (the self-licking and the nonlicking)were topically administered with 1 mg kg(-1) of eprinomectin. In the self-licking group, rabbits were allowed to self-lick freely, while, to prevent self-licking, each animal in the non-licking group was fitted with a pet collar. Compared to the non-licking group, self-licking behavior contributed to an extremely significant shorter half-life of absorption (14.85+/-2.79 h in licking group vs.29.44+/-7.81 h in non-licking group, p<0.01) and an extremely significant higher C(max) value for eprinomectin (21.95+/-5.36 h in licking group vs. 6.98+/-0.72 ng ml(-1) in non-licking group, p<0.01) in plasma disposition. An extremely significantly shorter mean residence time (50.72+/-3.45 h) in self-licking group was also determined compared with the value obtained in non-licking group (106.66+/-7.39 h; p<0.01). Clinical efficacy study of eprinomectin was examined in rabbits naturally infested with P. cuniculi which were randomly allocated in three groups: the self-licking, the non-licking, and control groups. All rabbits in the self-licking and the non-licking groups were treated with topical eprinomectin at a single dose of 2 mg kg(-1) (day 0). Topical eprinomection led to a complete parasitological recovery in both treated groups on day 14 and remained free of live mites and clinical lesions from day 21 to the end of the study period (day 35).

Pharmacokinetics of moxidectin following topical administration to New Zealand rabbits

“…Moxidectin was applied topically on the skin of the back between the last thoracic and the first lumbar vertebrae. To prevent self‐licking and to keep the ears from the dosing region, each animal was fitted with a pet collar with no impact on free access to food and water (Wen et al. , 2010).…”

“…Animal natural licking behavior could make an effect on the pharmacokinetics of a topically administered drug. It has been demonstrated that after the pour‐on administration of eprinomectin, a shorter t 1/2ab and a higher C max in self‐licking group were observed compared to nonlicking group in rabbits (Wen et al. , 2010).…”

Psoroptes cuniculi induced oxidative imbalance in rabbits and its alleviation by using vitamins A, D3, E, and H as adjunctive remedial

“…Ear mange mite Psoroptes cuniculi is frequently seen in rabbits and causes pruritus and crusting of the external ear canals, often leading to head shaking and drooping of the pinnae (Sant and Rowland 2009). Clinical infestation may lead to considerable weight loss, lower favorable feed conversion rates, listlessness, anorexia, meningitis, altered immune functions, and even death in laboratory rabbits (Ulutas et al 2005;Wen et al 2010). If infestation is not treated, it may cause serious economic loss due to mortality and morbidity in the infested rabbits.…”

“…However, multiple administrations or larger dosage are typically needed. Multiple treatments of ivermectin (Kurade et al 1996), doramectin (Kanbur et al 2008), selamectin (Farmaki et al 2009), moxidectin, and eprinomectin (Wen et al 2010) are reported to be effective against P. cuniculi in rabbits. A failure report on control of psoroptic mange was also issued that, with moderate or severe infestations in rabbits, parasites were still present after four weekly injections of ivermectin at a dose of 0.2 mg/kg (Kurade et al 1996).…”

Evaluating troponin C from Psoroptes cuniculi as a diagnostic antigen for a dot‐ELISA assay to diagnose mite infestations in rabbits

“…Psoroptes cuniculi is a common, globally distributed ectoparasite that can cause highly contagious ear mange in rabbits . P. cuniculi infections cause considerable weight loss, lower feed conversion rates, listlessness, anorexia, meningitis, altered immune functions and can be fatal if not treated .…”