Efecto del hipoclorito de sodio y extracto de cítricos en la reducción de la infestación con nematodos gastrointestinales resistentes a antihelmínticos en ovinos de pelo

the study included two experiments. the objective of experiment one was to learn about the in vitro effect of different sodium hypochlorite concentrations and a commercially-available citric extract on the survival of infestant larvae of gastrointestinal nematodes by observation at different time points. with >0.05% sodium hypochlorite concentrations, larvae lost their sheaths in two minutes, while at 1.3% concentration larvae died within one hour. larval mortality also occurred as late as 12 h after exposure to the concentrations tested of citric extract. the second study was performed to evaluate the effect of applying both compounds directly on the grasslands on the re-infestation of grazing sheep. eleven (11) lambs per treatment group were used, i.e.: treatment ti, untreated control; tii, application of one (1) liter 0.5% sodium hypochlorite/20 m2; tiii, application of 5% citric extract on the grass also at the rate of 1 l/20m2. data on live weight, packed cell volume (pcv), and nematode egg counts per gram (epg) of feces was analyzed using the glm (sas) procedure. the highest effect on epg and pcv was obtained in the group of lambs grazing the paddock treated with sodium hypochlorite, with the lowest epg and the highest pcv values as compared to both the controls and the group treated with citric extract (1,088 vs 1,997 and 2,891 epg; 25.6 vs 23.1 and 23.5 %, respectively; p<0.05).