Vesicular diseases in livestock may be associated with a group of viruses that have significant sanitary, economic and public health relevance. The main diseases of this group are foot and mouth disease (FMD), vesicular stomatitis (VS), bovine herpetic mammillitis (BHM) and the poxvirus infections as bovine vaccinia (BV), bovine papular stomatitis (BPS) and pseudocowpox (PCP). Malignant catarrhal fever (MCF) and bovine viral diarrhoea (BVD) may also

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The effects of oral supplementation of chromium picolinate (CrPic) on various blood parameters and their possible toxicity on the liver, kidneys, lungs, heart, and testis were investigated. Twenty-four Santa Inês (SI) lambs were treated with four different concentrations of CrPic (six animals/treatment): placebo, 0.250, 0.375, and 0.500 mg CrPic/animal/day for 84 days. The basal diet consisted of hay Panicum maximum cv Massai and concentrate. Blood and serum were collected fortnightly for analysis. On day 84, the animals were euthanized, and histopathological analysis in the liver, kidney, heart, lung, and testis was made. The liver and kidney were also submitted to electronic microscopy analysis. Differences between treatments (P < 0.05) were observed for packed cell volume (day 84), hemoglobin (day 84), total plasm protein (day 56 and day 84), and triglycerides (day 70). There was no statistically significant relationship between Cr supplementation and histopathology findings, although some animals treated with supplementary Cr showed morphological changes in the liver, kidney, and testis. Thus, the effectiveness of supplementation with Cr remains in doubt as to its physiological action and toxicity in sheep.

Magnetic nanoparticles can be used in different areas of biology. It is therefore important to know the effects of such nanomaterials on germline cells as they may traverse the blood-testis barrier. This work aimed to evaluate the response of bull sperm after exposure to a magnetic fluid containing DMSA-coated maghemite nanoparticles (MNP-DMSA) in order to determine nanotoxicity. Bull sperm was incubated with MNP-DMSA at final concentrations of 0.06, 0.03 or 0.015 mg Fe/mL. Sperm kinetics, plasma membrane integrity and acrosome reaction were evaluated over a 4 h incubation period. The sperm cells were also evaluated by transmission electron microscopy. Exposure of bull sperm to MNP-DMSA did not affect sperm kinetics or integrity. Neither ultrastructural damage of sperm cells nor uptake of nanoparticles by the spermatozoa was observed. In conclusion, MNP-DMSA does not affect sperm function or structure under the conditions tested.

The effects of oral supplementation of chromium picolinate (CrPic) on humoral and cellular immunity in sheep were investigated. Twenty-four male lambs divided into four treatments and received different dosages of CrPic: placebo (0), 0.250, 0.375, and 0.500 mg of chromium/animal/day during 84 days. The base ration was Panicum maximum cv Massai hay and concentrate. Blood samples were collected fortnightly for total and differential leukocyte counts. On days 28 and 56, the lambs were challenged with chicken ovalbumin I.M. Serum samples were collected on days 46 and 74 and subjected to an indirect enzyme-linked immunosorbent assay to measure IgG anti-ovalbumin. The cell-mediated immune response was determined by a delay-type hypersensitivity test using phytohemagglutinin. CrPic did not significantly affect humoral immunity in lambs but there was a negative effect on cellular immunity (P < 0.05) as Cr supplementation increased. Therefore, the level of Cr supplementation for lambs must be better studied to address its effect on stressed animals or the possible toxic effects of Cr on the animal itself or its immune system.