Liver lipidosis is a metabolic disorder mostly observed in high yielding dairy cattle, especially during the transition period. The aim of this study was to determine the correlation between hepatic lipid infiltration, biochemical indicators of liver function, and body condition score (BCS) variation in dairy cows. Fifty-one multiparous Holstein cows raised in a confined system were evaluated. Liver biopsies and blood samples were collected, and BCS was measured on days 3 and 28 postpartum. Lipid infiltration was determined by histologic examination. The plasma activity of aspartate aminotransferase, alkaline phosphatase, and gamma-glutamyl transferase and concentration of beta-hydroxybutyrate, non-esterified fatty acids, albumin, total bilirubin, and cholesterol were determined. BCS was measured using objective (camera) and subjective (visual) methods. Mild lipid infiltration was found in 3.92% of cows sampled on day 3 and 5.88% on day 28. Bilirubin was significantly higher on day 3 than on day 28 postpartum, and cholesterol was significantly higher on day 28 than on day 3 in all cows. There was no difference in biochemical analytes between cows with and without lipidosis. On day 3, mean subjective BCS was 3.10 and objective BCS was 3.16, while on day 28, these scores were 2.91 and 2.99, respectively. The calculated liver function index (LFI) was found to be a more sensitive indicator of liver function than the hepatic analytes evaluated. No correlation between BCS variation and lipid infiltration was found. Cholesterol and bilirubin levels showed the most remarkable changes during the early postpartum period. LFI is a potential indicator of postpartum liver function.

The objective of this study was to identify the effect of pre and postpartum DCAD on serum levels of calcium, phosphorus, and magnesium in peripartum Holstein cows. Blood samples were collected from 56 cows (18 primiparous and 38 multiparous) on days -7, +7, +14 and +28 relative to parturition, to determine serum levels of total and ionized calcium, phosphorus, magnesium, and albumin; diet samples for determination of calcium, phosphorus, magnesium and DCAD were collected at the same moments and urine samples were collected at day -7 for measurement of urinary pH. Prepartum DCAD was positively correlated with total calcium (p = 0.02) and with corrected total calcium (p = 0.01) at day -7. There was a negative correlation between prepartum DCAD and magnesium levels at day -7 (p = 0.02). No influence of prepartum DCAD on phosphataemia was observed. Postpartum DCAD did not correlate with serum mineral levels at any time point. Our results demonstrate that prepartum DCAD can influence calcium and magnesium homeostasis, but not phosphorus. In addition, parity and time period should be considered when evaluating serum levels of these minerals in Holstein cows during transition period.

No abstract

El hiperadrenocorticismo (HAC) es una de las endocrinopatías más frecuentes en caninos, producida por la síntesis excesiva de cortisol. El HAC atípico u oculto es un síndrome caracterizado por la presentación de alteraciones clínicas, bioquímicas e imagenológicas compatibles con hipercortisolismo, pero con resultados normales en las pruebas endocrinológicas utilizadas convencionalmente para diagnóstico de HAC. Sin embargo, estos pacientes presentan elevada concentración sérica de precursores u otras hormonas corticoadrenales. El presente estudio describe el caso de una canina hembra, Bichón Frisé de 8 años de edad, epiléptica y tratada con fenobarbital, presentando signos clínicos asociados a HAC, en la que el test de supresión con dexametasona a dosis bajas y de estimulación con ACTH arrojaron valores normales. La medición de esteroides adrenales, post estimulación con ACTH, mostró elevación anormal de estrógenos y progesterona, persistiendo esta última después de que la paciente fuera esterilizada. El tratamiento con trilostano permitió la disminución de los niveles de progesterona y la resolución parcial de los signos clínicos. Sin embargo, la recuperación clínica en su totalidad sólo se obtuvo después del diagnóstico y tratamiento del hipotiroidismo concomıtante. El desafío que representa el diagnóstico del HAC atípico resalta la importancia de realizar y disponer de paneles que incluyan medición de hormonas esteroideas adrenales diferentes al cortisol, además de considerar la ocurrencia de otras enfermedades endocrinas metabólicas concomitantes.