Cryptosporidium and Giardia species infections in sheep from Brazil and associated risk factors

Cryptosporidium and Giardia genus negatively impact the production of small ruminants. This study aimed to determine the prevalence of infection by Cryptosporidium spp. and Giardia spp. and to assess associated risk factors in sheep from Brazil. We collected fecal samples (n = 459) from animals aged up to twelve months old. Samples were processed using formalin-ether centrifuge-sedimentation techniques with modified Ziehl-Neelsen staining for Cryptosporidium spp. and zinc sulfate centrifuge-flotation for Giardia spp. We calculated the Odds Ratio (OR) to determine associations between different variables and positivity. In total, 27.45 % (n = 126/459; 95 % CI = 23.57 – 31.71) of the animals were infected by Cryptosporidium spp., 13.29 % (n = 61/459; 95 % CI = 10.49 – 16.70) by Giardia spp., and in 3.05 % (n = 14/459; 95 % CI = 1.83 – 5.05) both parasites were detected. Cryptosporidium spp. (χ2 = 28.373; p < 0.0001) predominated in the sheep population. Intensive farming (OR = 3.87; p < 0.0001), herds with 51–80 animals (OR = 3.60; p < 0.0001), no chloride water (OR = 2.0; p = 0.0167), no manure removal (OR = 3.2; p < 0.0001), dirt floors (OR = 6.8; p < 0.0001), and the presence of flies (OR = 2.0; p = 0.0096) were considered risk factors for Cryptosporidium spp. infection. The presence of cohabitating species (OR = 2.1; p = 0.0358) and the presence of dogs or cats (OR = 4.5; p < 0.0001) were risk factors for Giardia spp. infections. Our data demonstrate the need to implement prophylactic actions on the evaluated properties to minimize economic losses and the impact on overall health resulting from infections by Cryptosporidium spp. and Giardia spp.