CCB. Artículos indexados en Scopus · 2026

Using biological control in free-range laying hens to prevent infections by digestive endoparasites. effects on productivity, welfare and health

Controlling endoparasites in free-range laying hens remains a challenge, as the existence of infective stages in the soil poses a continuing risk of infection. To reduce the presence of oocysts and nematode eggs in the soil, the saprophytic filamentous parasitophagous fungus Mucor circinelloides was distributed in the shelters and pens of two small-scale poultry farms following a two-phase protocol. In the first trial, the conditioning phase involved spraying fungal spores in two pens every three days for eighteen or nine days before 16-week-old Lohmann Brown-Classic pullets were housed; subsequently, the maintenance phase consisted of spraying the spores every two weeks for one month; in another plot, water was sprayed (untreated controls). Oocysts of Eimeria spp., and eggs of Ascaridia galli and Capillaria spp. were identified in the bird feces, which reduced by 65-95% (χ2z = 25.471,P = 0.001), 84-100% (χ2= 159.992, P = 0.001), and 75-89% (χ2= 206.074, P = 0.001), respectively, in the plots sprayed with fungal spores. Trial 2 was performed into two plots and comprised a conditioning phase (with spores) of nine days followed by a maintenance phase of 10 months, and another control plot (water-sprayed). Oocysts of Eimeria spp. and eggs of A. galli were detected in the feces, and their values decreased by 71-95% (χ2=165.212, P = 0.001) and 67-100% (χ2= 137.684, P = 0.001), respectively. In both trials, similar results were obtained for body weight, laying rate (% laying / bird / day), and the numbers of eggs per housed bird, as well as for egg characteristics (weight, freshness, shell thickness, and yolk color). It is concluded that spraying of M. circinelloides in shelters and pens of small-scale poultry farms following a biphasic protocol provides a useful tool for applying this biocontrol agent to reduce the risk of infection by digestive endoparasites in free-range laying hens, without affecting their health, welfare, egg production or quality. Further studies on a larger number of birds are needed to confirm these results.