Abstract This study evaluated of the effects of açai oil during the close-up dry period of Holstein cows on colostrum quality, as well as on the immune and antioxidant responses of their calves. Sixteen multiparous cows were assigned randomly to two treatments: 1) CONTROL (n = 8) - 4.48% of soybean oil/concentrate; 2) AÇAI (n =8) - 4.48% of açai oil/concentrate. Cows fed with açai oil had greater (P≤0.04) colostrum concentrations of immunoglobulins (Ig) G (1st and 2nd milking), IgG heavy chains, IgA (only at 1st milking), alpha-lactalbumin (1st milking), total protein, and antioxidant capacity against peroxyl radicals (only at 1st milking). Cows fed with açai oil had greater serum concentrations of globulin (only on the day of calving) and total protein (only on the day of calving) (P = 0.03). Calves born of cows fed with açai oil had greater serum concentrations of total protein (only 24 and 48 h after calving) and serum concentration of IgG heavy chain (only 24 h after calving) and globulin (only 24 and 48 h after calving) (P = 0.01). These data suggest that the addition of açai oil in the cow feed during the close-up dry period boosted immunity in their calves by altering the composition of colostrum.

RESUMEN Objetivo. Evaluar si la calidad del calostro se modifica por las características genéticas, fisiológicas y de manejo en el período preparto, así como evaluar si la calidad y composición del calostro se alteran en el proceso de congelación. Material y métodos. En el experimento I, se recogieron muestras de calostro y sangre de 35 vacas (18 Holstein y 17 Jersey). En el experimento II, se recolectaron seis muestras de calostro de vacas Holstein y se congelaron durante 60 días. Resultados. La concentración media de inmunoglobulina G (IgG) fue de 77.65 mg/ml en Jersey y de 82.77 mg/ml en Holstein. La genética, el orden de parto y la interacción entre estos factores no fueron significativos en la concentración de IgG en el calostro. Además, se observó un efecto genético de la vaca en el peso en la cría al nacer y en los tres días de edad (p<0.0001). Con respecto a la transmisión de inmunidad pasiva de terneros, no se observaron efectos de la raza de la vaca y el orden de parto en la concentración de proteínas plasmáticas de la ternera, así como después de tres días de congelación. Las razas de becerros Holstein (83%) y Jersey (82%) mostraron niveles de proteína sérica total por encima de 5.5 g/dL. Las vacas Holstein alojadas en potreros individuales con suplementos dietéticos, proporcionaron una mejor calidad de calostro (93.57 mg IgG/mL). Con el tiempo, el porcentaje de grasa cambió al congelarse, que se redujo con el tiempo (p<0.05) en el Experimento II. Conclusiones. El manejo previo al parto influye en la calidad del calostro, y la congelación no interfiere en la calidad centesimal e inmunológica del calostro, con excepción de la grasa, que disminuye a lo largo del tiempo.

ABSTRACT Objective. The aims of this study were to assess whether colostrum quality is modified by genetic, physiological and management characteristics in the pre-partum period, as well as evaluate whether quality and composition of colostrum is altered in the freezing process. Material and methods. In the experiment I, colostrum and blood samples of 35 cows (18 Holstein and 17 Jerseys) were collected. In the experiment II, six colostrum samples of Holstein cows were collected and frozen during 60 days. Results. The mean immunoglobulin (Ig) concentration was 77.65 mg/ml to Jersey and 82.77 mg/ml to Holstein. The genetic, parturition order, and the interaction between these factors were no significant on IgG concentration in the colostrum. Also, it was observed an effect genetic of cow in the weight on calf at birth and on three days of age (p<0.0001). Regarding transmission of calf passive immunity, no effects of cow breed and calving order were observed on plasma protein concentration of calf, as well as after three days of freezing. Calves of Holstein (83%) and Jersey (82%) breed showed total serum protein levels above 5.5 g/dL. Holstein cows housed in individual paddocks with diet supplementation provided better quality of colostrum (93.57 mg Ig/mL). Over time, the percentage of fat reduced at freezing, that reduced over time (p<0.05) in Experiment II. Conclusions. The pre-partum management exerts influence on colostrum quality, and the freezing not interfere on centesimal and immunological quality of colostrum, with exception the fat, that decrease along the time.

Abstract: The aim of this study was to evaluate whether the use phytogenic as feed additive of Holstein calves could exert beneficial effects on animal health and performance. Thirty newborn calves were randomly divided into two groups (control and treated), and the treated consisted of 10 g of the phytogenic product diluted in milk once a day for 30 days. Blood and fecal samples were collected, and fecal score was performed daily in order to determine the occurrence of diarrhea. Treated calves showed higher hematocrit on days 45 and 60 of life. Serum levels of urea, total proteins, globulins and glucose were lower in the treated group on day 60 of life, while triglycerides were lower on days 15 and 60 of life. Serum glutathione S-transferase activity was higher in treated animals on day 60 of life. Fecal bacterial count was lower in treated animals on days 30 and 60 of life. The weight gain was higher in treated animals on days 60 and 210 of life. Based on these results, it is possible to conclude that the addition of phytogenic as feed additive for calves was able to minimize fecal bacterial infections and to increase body weight gain.