Evaluation of the supply of Duddingtonia flagrans for the control of gastrointestinal parasites in sheep.

Parasitic resistance imposes alternative control methods, like nematophagous fungi. In this study, two experiments were conducted supplying Duddingtonia flagrans aiming to evaluate the biological control of parasites in sheep. In the first, 24 sheep naturally infected by gastrointestinal nematodes were allocated, in randomized blocks, following the treatments: control or treated group, 0.5g/animal product containing D. flagrans, chlamydospores. Weight, body score, Famacha©, egg count per gram of feces (EPG), and larval percentage were evaluated. In the second experiment, D. flagrans (0.25 and 0.5g product) was infested with manure, plus or not protein concentrate, in a completely randomized design. In both experiments the dose was intentionally lower than recommended. Recovery and larval identification were performed. The SAS analyzed the variables by the MIXED procedure, repeated measures in time. Weight, body score, hematocrit, and Famacha© did not show differences between treatments (p>0.05); however, EPG (p<0.001) and the percentage of larvae identified in coproculture were different. In the second experiment, the inclusion of the fungus did not influence the recovery of larvae (p>0.05). In both experiments, colonization and advancement of the fungus were visualized. Under the experimental conditions, the fungus D. flagrans was not effective in the biological control of parasitic infection in sheep.

Characteristics of growth, carcass and meat quality of sheep with different feed efficiency phenotypes.

The objective was to evaluate the performance, carcass and meat quality of 40 lambs classified by RFI (residual feed intake) and RIG (residual intake and gain). Dry matter intake (DMI) was recorded to calculate the RFI and RIG, classified as efficient, moderately or inefficient. After the confinement period, they were slaughtered and the carcass and meat quality were determined. The efficient animals had DMI scores of 0.700 RFI and 0.400 kg/d RIG, lower than the inefficient ones with similar weight gain. The RFI efficient animals showed greater shear force, without effect in the RIG classification. In general, the variables analyzed were not influenced by RFI or RIG. Efficiency measures do not affect the carcass and meat quality of sheep, but they do have the advantage of identifying animals with lower feed consumption, making the system more efficient. However, as the dataset is limited to fully assess the effects, this manuscript can be used as preliminary results for future studies.