Comparación de la efectividad antihelmíntica de seis productos comerciales que contienen lactonas macrocíclicas frente a nemátodos gastrointestinales del bovino

Anthelmintic resistance of injectable macrocyclic lactones in cattle: A systematic review and meta-analysis

“…Most of the studies included in this SR and MA reported using a dosage of 0.2mg/Kg (ALONSO-DIAZ et al 2015;ARANTES et al, 1995;CANUL-KU et al, 2012;CONDI et al, 2009;LLORENS et al, 2014;MENA et al, 2008;RANGEL et al, 2005;RANJAN et al, 1992;SIEVERS & FUENTEALBA, 2003;SIEVERS & ALOCILLA, 2007;STAFFORD & COLES, 1999). Correct dosing in the application of anthelmintic drugs may prevent the development of AHR (LESPINE et al, 2012), but farmers sometimes treat animals at dose rate below those recommended by the manufacturer.…”

“…Only studies that presented low risk of selection bias based on random sequence generation, random allocation concealment, blinding of outcome assessment, incomplete outcome data and selective outcome reporting were included in the quantitative synthesis (n=5). The studies selected here were published between 1992 and 2012: (i) Condi et al (2009); (ii) Canul-Ku et al (2012); (iii) Geurden et al (2004); (iv) Ranjan et al (1992) and (v) Sievers and Fuentealba (2003). The outcome was calculated based on the number of sample sizes and the number of events, where the sample sizes were the total number of cattle treated (Moher et al, 2010), showing the total number of records identified and the number of records filtered at each stage of the selection process from the systematic review and meta-analysis.…”

Drug resistance in parasitic helminths of veterinary importance in Chile: Status review and research needs

“…Gastrointestinal nematodes. Three published studies have declared the presence of AR in GI nematodes infecting ruminants in Chile (Sievers and Fuentealba 2003, Sievers and Alocilla 2007, Toro et al 2014. Unpublished theses have also explored the field efficacy of anthelmintic drugs and AR in cattle farms in Southern Chile.…”

“…To date, no research has confirmed the presence of drug-resistant ruminant nematodes by CET or genotyping of resistant isolated from Chilean farms. Sievers and Fuentealba (2003) studied the field efficacy of six formulations (subcutaneous) of either ivermectin (IVM), moxidectin (MOX), abamectin (ABM) or doramectin (DOR) against GI nematodes in naturally infected calves (~one-year old; n=84) in a farm from the Osorno province (Los Lagos Region). At day 14 post-treatment, the authors reported a mean FECR% of 94-100% for IVM, 98% for MOX and 100% for ABM and DOR treatments.…”

“…In that study, the observed efficacy reductions between days 14 and 21 post-treatment correlates with the known inhibition of egg excretion by ML-exposed worm females, which results in an apparent higher efficacy at day 14 post-treatment and the resumption of egg excretion by the surviving worms at day 21 post-treatment. Despite the 95% confidence intervals of the FECR% were not described for any treatment, thus preventing the declaration of AR based on available guidelines, the reported results were generally below the threshold of mean FECR ≥ 95% expected with efficacious treatments (Sievers and Fuentealba 2003). Subsequently, Sievers and Alocilla (2007) investigated the presence of IVM-resistant GI nematodes in naturally infected calves (7-8 months-old; n=14/22) from two cattle farms in the Osorno province with distinct history of ML use.…”