RESUMO
Cattle lameness remains a significant concern, causing economic losses and compromising animal welfare. Claw horn lesions have been identified as a major cause of lameness in dairy cows but its correlation with high-energy diet and ruminal acidosis remains unclear. Hence, the primary objective of this study was to assess the effects of a high starch and a conventional diet on the rumen environment, acute phase proteins, and metabolic alterations, with a particular focus on insulin resistance and the consequent implications for the histology of the hooves in Holstein steers. Sixteen animals were divided into the high-starch (HS; 37% starch) and conventional (CON; 16.8% starch) groups. Glucose tolerance tests (GTT), blood, rumen fluid analysis, and histological evaluations of the hoof tissue were conducted over a 102-d experimental period. The HS group showed a lower ruminal pH than the CON group, and with values indicating subacute ruminal acidosis (SARA). The plasma glucose and IGF-1 concentrations were higher in the HS group, suggesting an anabolic state. Both groups exhibited an increase in the insulin area under the curve (AUC) after the GTT on d 102. Histological analysis of the hooves showed a reduction in the length and width of the epidermal lamella in both groups. There was a significant negative correlation between the insulin AUC and the length and width of the epidermal lamella. Since both groups were similarly affected, the hypothesis that histological alterations were caused by the experimental diets still needs confirmation. Additionally, the development of SARA was not essential for the observed histological changes in the hoof. Further studies are warranted to thoroughly investigate the role of insulin and IGF-1 imbalances in claw health.
RESUMO
Background: Primary neoplasms of the nasal cavity and sinuses are uncommon in domestic animals, most of which are of epithelial origin, being adenocarcinoma the most common tumor diagnosed in this region. Some malignant nasal cavity neoplasms may invade the brain causing clinical neurological signs, as well as purulent nasal secretion and epistaxis. Case Description: A case of neoplasm is reported in a 14-year-old pincher presenting dyspnea, epistaxis, and neurological alterations. Necropsy revealed the presence of a mass in the oral cavity vestibule, and another in the whole nasal cavity with invasion of the cribiform plate, meninges and brain. Squamous cells carcinoma was diagnosed in the oral cavity and transitional carcinoma in the nasal cavity. The immunohistochemistry confirmed that the brain infiltration was of the same origin as the nasal cavity neoplasm. Conclusion: The present report describes a rare case of transitional carcinoma of the nasal cavity as well as the frontal and ethmoidal sinuses with brain invasion, confirmed by immunohistochemistry. It is extremely important for veterinarians to include neoplasms in their differential diagnoses, when these animals show chronic respiratory signs and neurological alterations that do not improve with appropriate treatment, always associating with complementary exams, for correct diagnosis establishment and prognosis formulation.
