Carlos Saumell's research while affiliated with Facultad Latinoamericana de Ciencias Sociales - Argentina and other places

... All parameters studied (pasture larval infectivity, L3 remaining in faecal pats and faecal cultures as in vitro corroboration) showed very high fungal trapping activity in these seasons, despite the fact that the E:C ratios used in each season were different. The high larval reductions obtained in spring, summer, and autumn in both the faecal cultures and pasture infectivity are in agreement with previous reports demonstrating that large variations in FEC in cattle-and, consequently, variations in the E:C ratio at the moment of administering fungal chlamydospores-do not present an obstacle for the efficacy of D. flagrans on cattle nematodes [51]. ...

... Numerous studies in many countries have confirmed the insecticidal activity of ivermectin residues and that of other endectocides in dung to non-pest species of dung-breeding insects (Floate et al. 2005;Jacobs and Scholtz 2015;Junco et al. 2021;Lumaret et al. 2012). In Canada, recommended topical doses of ivermectin (Floate 1998b) or doramectin (Floate et al. 2008), respectively, have been shown to reduce numbers of insects developing in dung deposited by cattle up to 12 and 16 weeks post-treatment. ...

... The overall reduction percentage of larvae was 94% and the number of active nets was greater when the epg and the number of larvae increased. A study carried out in sheep by Sagües et al. (2020) four concentrations of chlamydospores of the same fungus in a bovine trial, concluding that the number of nematodes in cattle feces is not a determining factor to stimulate the fungus's predatory capacity. It could be speculated that the lower efficacy of the fungus could be due to the conditions that are created within the fecal matter. ...

... There are, however, other reasons to develop alternative control measures, which nevertheless are related to the massive use of chemical anthelmintics. Chief amongst these is the problem of anthelmintic residues and environmental contamination, which that are harmful in several ways (e.g., affecting non-target, beneficial organisms in soil, faeces, and water as well as pasture and vegetable plants) [6][7][8][9][10]. ...

... In most cases, the use of this tool has been confined to geographical areas with a reduced grazing season [20][21][22] or tropical/subtropical areas where seasonal changes throughout the year that can have a deep impact on fungal-nematode interactions are not well marked [23][24][25][26][27]. There have been very few reports where the main nematophagous fungus studied so far, Duddingtonia flagrans, has been tested in different seasons [28,29]. The challenge is to apply biological control in actual livestock production systems taking into consideration the various factors-environmental, parasitic, etc.-affecting the fungus-parasite interaction. ...

... Diferent methods for ivermectin detection have been reported by several authors.Åsbakk et al. used highperformance liquid chromatography (HPLC) with fuorescence detection to detect ivermectin in feces from reindeers [12]. Iglesias et al. used the same method for soil and cattle feces [13]. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) has also been shown in several studies to be useful for multiple matrixes such as plasma, milk, liver, and whole blood [14][15][16][17][18][19][20]. ...

... Similarly, the plasma IVM concentration was reduced in horses fed with sainfoin from 24 h onwards in our study. It is generally reported that the T max (time to peak plasma concentration) is 8 h for oral IVM treatment in horses (Gokbulut et al., 2001;Saumell et al., 2017;Vyniarska et al., 2021). The measure at 8 h post-treatment was not practically feasible under our setting. ...

... Los resultados para doramectina son similares con lo reportado por Cerna (2007) una mutación del gen de la beta-tubulina en nematodos de rumiantes y en varias especies comunes de ciatostomas les confiere la capacidad de resistencia a este grupo farmacológico. La resistencia a los compuestos antihelmínticos es un problema de preocupación mundial, que se da en la ganadería, particularmente en crianza bajo sistemas de pastoreo (Steffan et al., 2014); siendo la heredabilidad de la resistencia la característica más importante de este fenómeno (Kassai, 2002). ...

... Improved forage species and rations are low in concentration and profiles of PSMs given their potential toxic effects (see previous section). However, PSMs at the appropriate dose could provide medicinal benefits (e.g., Moreno et al., 2010). In addition, there is evidence that herbivores learn about these benefits and potentially selfmedicate (Engel, 2003;Hutchings et al., 2003). ...

... En el año 2000 se comunicó por primera vez en Argentina la resistencia a los antihelmínticos de nematodes gastrointestinales bovinos 1,15 . La mayoría de los hallazgos sobre resistencia antihelmíntica involucran drogas del grupo de las lactonas macrocíclicas 2,16,19,25 , aunque más recientemente se estableció también resistencia a los benzimidazoles 3,17,19,25 . El estatus más actual sobre resistencia antihelmíntica a nivel nacional corresponde a datos ob-tenidos por el Proyecto de Cooperación Técnica asistido por la FAO en el año 2004, en el cual los resultados del Test de Reducción de Conteo de Huevos (TRCH) en materia fecal señalaron un gran número de establecimientos con resistencia a la ivermectina (55%) 7 . ...