Economic impact of gastrointestinal nematodes in Morada Nova sheep in Brazil

Abstract

This study evaluated the economic impact of gastrointestinal nematode (GIN) infection in Morada Nova lambs under different parasite chemical control conditions. For this, 246 lambs, in the rainy and dry season, were randomized into groups according to their anthelmintic treatment with levamisole: control (CT: no treatment); routine treatment (RT: treated every 42 days); and targeted selective treatment (TST: treated according to the average daily weight gain, DWG). From 63 days of age (D63) to D210, the lambs were weighed and monitored for GIN infection parameters. Spending on anthelmintics in the production system was 1.3% of the total economic result. The economic result per animal (R$ 5.00 = US$ 1.00) was higher in the RT group, amounting to US$ 6.60 in the rainy and US$ 5.69 in the dry season, due to higher DWG. Thus, RT presented economic results 14.4% and 10.9% higher than CT, and 7.2% and 1.9% higher than TST, in the rainy and dry season, respectively. However, fast development of resistance made RT unfeasible. Here, the economic impact of GIN infection on a national scale is discussed, demonstrating its importance and the impossibility of profitable and sustainable sheep production without adequate control.

Phenolic Acids and Flavonoids from Pithecellobium dulce (Robx.) Benth Leaves Exhibit Ovicidal Activity against Haemonchus contortus

“…Due to its hematophagous habits, H. contortus can cause severe damage to the animals, thus affecting their zootechnical potential [ 2 ]. In livestock, infections with H. contortus are difficult to control, resulting in high economic losses worldwide (Corwin, 1997; Rodríguez-Vivas et al, 2017) [ 3 , 4 ]. In addition, the frequent and continuous use of chemical anthelmintic drugs has led to anthelmintic resistance worldwide.…”

Polymorphisms in exon 11 of the mptl-1 gene and monepantel resistance in Haemonchus contortus

“…Gastrointestinal nematode infections, especially those caused by H. contortus (the barber's pole worm), are responsible for large economic losses in sheep production owing to decreased performance, treatment expenses, and anthelminthic resistance (Miller et al 2012;Chagas et al 2022). As anthelmintic resistance has become a worldwide problem, tests for resistance using molecular markers are an attractive alternative for the identi cation of early resistance emergence, supporting decisions on treatment management (Gasser et al 2008).…”