The aims of this study were to verify the prevalence of Cryptosporidium spp. and Giardia spp. in animal feces and drinking water on dairy farms and to identify a possible relation between the exposure factors and the presence of these parasites. Fecal samples from cattle and humans and water samples were collected on dairy farms in Paraná, Brazil. Analysis of (oo)cysts in the feces was performed by the modified Ziehl-Neelsen staining and centrifugal flotation in zinc sulfate. Test-positive samples were subjected to nested PCR amplification of the 18SSU ribosomal RNA gene for identification of Cryptosporidium and Giardia and of the gp60 gene for subtyping of Cryptosporidium. Microbiological analysis of water was carried out by the multiple-tube method and by means of a chromogenic substrate, and parasitological analysis was performed on 31 samples by direct immunofluorescence and nested PCR of the genes mentioned above. Identification of the species of Cryptosporidium was performed by sequencing and PCR with analysis of restriction fragment length polymorphisms. The prevalence of Giardia and Cryptosporidium was higher in calves than in adults. Among the samples of cattle feces, Cryptosporidium parvum was identified in 41 (64%), C. ryanae in eight (12.5%), C. bovis in four (6.3%), C. andersoni in five (7.8%), and a mixed infection in 20 samples (31.3%). These parasites were not identified in the samples of human feces. Thermotolerant coliform bacteria were identified in 25 samples of water (45.5%). Giardia duodenalis and C. parvum were identified in three water samples. The gp60 gene analysis of C. parvum isolates revealed the presence of two strains (IIaA20G1R1 and IIaA17G2R2) in the fecal samples and one (IIaA17G2R1) in the water samples. The presence of coliforms was associated with the water source, structure and degradation of springs, rain, and turbidity. The prevalence of protozoa was higher in calves up to six months of age. C. parvum and G. duodenalis were identified in the water of dairy farms, as were thermotolerant coliforms; these findings point to the need for guidance on handling of animals, preservation of water sources, and water treatment.

The purpose of this study was to investigate the occurrence of Cryptosporidium spp. and Giardia spp. in a public water-treatment system. Samples of raw and treated water were collected and concentrated using the membrane filtration technique. Direct Immunofluorescence Test was performed on the samples. DNA extraction using a commercial kit was performed and the DNA extracted was submitted to a nested-PCR reaction (n-PCR) and sequencing. In the immunofluorescence, 2/24 (8.33%) samples of raw water were positive for Giardia spp.. In n-PCR and sequencing, 2/24 (8.33%) samples of raw water were positive for Giardia spp., and 2/24 (8.33%) samples were positive for Cryptosporidium spp.. The sequencing showed Cryptosporidium parvum and Giardia duodenalis DNA. In raw water, there was moderate correlation among turbidity, color and Cryptosporidium spp. and between turbidity and Giardia spp.. The presence of these protozoans in the water indicates the need for monitoring for water-treatment companies.

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The objectives of this prospective, experimental study were to describe changes in the stiffness of the equine superficial digital flexor tendon (SDFT) after induced injury, deep digital flexor tendon (DDFT), accessory ligament (AL‐DDFT), and suspensory ligament (SL) during 90 days of healing using acoustic radiation force impulse (ARFI) elastography. Eight healthy horses were selected. Preinjury B mode and ARFI evaluations were performed bilaterally in the palmar metacarpal region. Injury was induced only on the left forelimb (G2) by a single injection of collagenase in SDFT, 15 cm distal to the accessory carpal bone. The right forelimb was used as a control (G1). Evaluations were performed at eight timepoints: one before injury (T0) and seven (T1‐T7) after injury (3, 15, 30, 40, 60, 75, and 90 days post‐induction). Tendinopathies were visualized as hypoechoic areas with loss of parallel tendon fiber pattern. Injured SDFTs presented mainly cool colors (soft) from T1 to T3, and from T4, there was an increase in warm colors (hard), close to the appearance of tendons of G1. In the first four timepoints, there was a decrease in stiffness compared to G1 (P < 0.001). On T1 and T2, a cutoff value <6.21 m/s to determine tendinopathy of the SDFT was established (75.8% sensitivity and 92.03% specificity). Stiffness changes in the DDFT, AL‐DDFT, and SL of injured limbs occurred at different timepoints. Tendinopathy significantly altered the stiffness of the injured tendon and the adjacent tissues. ARFI made it possible to detect these changes, helping to monitor the reparation of this injury.

Sucrose- and diuretics-based protocols are widely used to induce osmotic diarrhea and dehydration in calves, but they fail to cause metabolic acidosis. In previous studies, calves were fed milk replacers and deprived of water. In this study, we assessed the water, electrolyte, and acid-base imbalances in calves that were fed whole milk and were not completely deprived of water during the induction period. Healthy, male Holstein calves aged 10-12 days were assigned to two groups: free access to water (FWG; n=17) and water deprivation at night (DWG; n=21); and osmotic diarrhea was induced with sucrose added to milk, spironolactone (2mg kg-1) and hydrochlorothiazide (2mg kg-1) orally every 8h for 48h. pH, pCO2, HCO3-, BE, Na+, K+, Cl-, SID3, TPP, AG, Atot, glucose, L-lactate, D-lactate, SIG, and percentage change in plasma volume were measured in venous blood samples taken at 0, 24, and 48h. Data were analyzed using two-way repeated measures ANOVA. Calves showed diarrhea, mild (FWG) to moderate (DWG) dehydration, hyponatremia, and moderate (FWG) to severe (DWG) metabolic acidosis. AG and D-lactate levels were higher and SIG was lower in the DWG, and there was no hyper-L- or D-lactatemia. The magnitude of metabolic acidosis was similar to that observed in natural cases of diarrhea. The protocol for inducing osmotic diarrhea and dehydration should be applied to calves that are fed whole milk and are not completely deprived of water.