ABSTRACT
El uso de antibióticos en el tratamiento de la mastitis en la industria lechera ha acarreado una problemática con potencial impacto en la salud pública, como la resistencia antimicrobiana. El objetivo del presente trabajo fue evaluar la acción antimicrobiana del extracto alcohólico de hojas, tallos y flores de Tithonia diversifolia sobre el crecimiento de Staphylococcus aureus y Escherichia coli en cultivo in vitro. Se evaluó el efecto inhibitorio en el crecimiento bacteriano a través de un ensayo de sensibilidad. En ambas bacterias el control positivo presentó un halo de inhibición superior a 30 mm, con diferencia significativa de los extractos de T. diversifolia. Los cuales presentaron para S. aureus un halo de 9,7 y 10,4 mm y para E. coli de 6,5 y 9,4 mm para tallo-hoja y flores respectivamente. El extracto alcohólico de flores de T. diversifolia se perfila como una herramienta potencial para inhibir el crecimiento bacteriano.
Antibiotics used as a treatment for mastitis in the dairy industry have brought a problem with a potential impact on public health, such as antimicrobial resistance. The objective of this study is to evaluate the antimicrobial action of alcoholic extract from Tithonia diversifolia's leaves, stems, and flowers on the growth of Staphylococcus aureus and Escherichia coli in in vitro cultures. The inhibitory effect on bacterial growth was evaluated through a sensitivity test. In both bacteria, the positive control presented an inhibition halo greater than 30 mm, with a significant difference from the extracts of T. diversifolia, which presented, for S. aureus, a halo of 9.7 and 10.4 mm and for E. coli of 6.5 and 9.4 mm for stem-leaf and flowers respectively. The alcoholic extract of T. diversifolia flowers is emerging as a potential tool to inhibit bacterial growth.
ABSTRACT
The main aim of the present study was to examine the effects of long-term supplementing diets with saturated or unprotected polyunsaturated fatty acids from two different plant oils rich in either n-3 or n-6 fatty acids (FAs) plus docosahexaenoic acid (DHA)-rich algae on mammary gene expression and milk fat composition in lactating dairy cows. Gene expression was determined from mammary tissue and milk epithelial cells. Eighteen primiparous German Holstein dairy cows in mid-lactation were randomly assigned into three dietary treatments that consist of silage-based diets supplemented with rumen-stable fractionated palm fat (SAT; 3.1% of the basal diet dry matter, DM), or a mixture of linseed oil (2.7% of the basal diet DM) plus DHA-rich algae (LINA; 0.4% of the basal diet DM) or a mixture of sunflower oil (2.7% of the basal diet DM) plus DHA-rich algae (SUNA; 0.4% of the basal diet DM), for a period of 10 weeks. At the end of the experimental period, the cows were slaughtered and mammary tissues were collected to study the gene expression of lipogenic enzymes. During the last week, the milk yield and composition were determined, and milk was collected for FA measurements and the isolation of milk purified mammary epithelial cells (MECs). Supplementation with plant oils and DHA-rich algae resulted in milk fat depression (MFD; yield and percentage). The secretion of de novo FAs in the milk was reduced, whereas the secretion of trans-10,cis-12-CLA and DHA were increased. These changes in FA secretions were associated in mammary tissue with a joint down-regulation of mammary lipogenic enzyme gene expression (stearoyl-CoA desaturase, SCD1; FA synthase, FASN) and expression of the regulatory element binding transcription factor (SREBF1), whereas no effect was observed on lipoprotein lipase (LPL) and glycerol-3-phosphate acyltransferase 1, mitochondrial (GPAM). A positive relationship between mammary SCD1 and SREBF1 mRNA abundances was observed, suggesting a similar regulation for these genes. Such data on mammary gene expression in lactating cows presenting MFD contribute to strengthen the molecular mechanisms that govern milk fat synthesis in the mammary glands. In purified MEC, the dietary treatments had no effect on gene expressions. Differences between mammary tissue and milk purified MEC gene expression were attributed to the effect of lipid supplements on the number of milk purified MEC and its RNA quality, which are determinant factors for the analysis of gene expression using milk cells.
Subject(s)
Animal Feed/analysis , Cattle/physiology , Docosahexaenoic Acids/administration & dosage , Down-Regulation/drug effects , Fatty Acids/metabolism , Linseed Oil/administration & dosage , Lipids/biosynthesis , Plant Oils/administration & dosage , Animal Nutritional Physiological Phenomena , Animals , Arecaceae , Cattle/genetics , Diet/veterinary , Dietary Fats/administration & dosage , Dietary Supplements/analysis , Epithelial Cells/enzymology , Epithelial Cells/metabolism , Fatty Acids/analysis , Fatty Acids, Unsaturated/metabolism , Female , Gene Expression Regulation, Enzymologic/drug effects , Lactation , Mammary Glands, Animal/enzymology , Mammary Glands, Animal/metabolism , Milk/chemistry , Polymerase Chain Reaction/veterinary , RNA, Messenger/analysis , Rumen/metabolism , Sterol Regulatory Element Binding Protein 1/metabolism , Sunflower OilABSTRACT
Se presenta una revisión sobre la composición, estructura y mecanismo de síntesis de la grasa de la leche en la glándula mamaria bovina y del efecto de la suplementación con ácidos grasos insaturados (AGI) sobre la cantidad y calidad de la grasa. Se resalta la importancia de la suplementación con aceites vegetales más aceite de pescado; se sugiere no generalizar el efecto de AGI como negativo sobre la cantidad de grasa de la leche; se muestra la necesidad de relacionar diferentes AGI con la vía regulatoria SREBP y con diferentes enzimas lipogénicas; y se incentiva la investigación del efecto de AGI sobre la composición de ácidos grasos de la leche y su distribución posicional dentro de la estructura lipídica.
Subject(s)
Cattle , Fats , Fatty Acids , Lipids , MilkABSTRACT
This study evaluated the effect of diet on fatty acid profile, vitamins, trace elements, lipid peroxidation, and quality of longissimus muscle of German Simmental bulls. The effect of storage on fatty acid profile and vitamins was also included. A control group was fed concentrate including soybean, and maize silage/grass silage. Treatment group I (unrestricted) was fed concentrate including rapeseed, and grass silage. Treatment group II (restricted) was fed like treatment group I with a feed restriction period. The treatment diet was not effective to give similar daily live weight gain to the control diet, but it was successful in improving beef fatty acid composition without affecting tenderness and colour (under unrestricted conditions). There were no differences in vitamins and cooking loss, but selenium decreased in treatment groups. Stimulated lipid peroxidation, in samples taken immediately post-mortem, was higher in treatment groups. Polyunsaturated fatty acids decreased, saturated fatty acids and intramuscular fat increased after 14days of storage while vitamins had no significant reduction.
ABSTRACT
This study was conducted to evaluate if supplementing bypass fat to cows under silvopastoral systems, increases the concentration of unsaturated fatty acids in milk, thus improving the saturated/ unsaturated ratio without a negative effect on total milk yield in fat or protein. Two concentrations of two different sources of bypass fat were evaluated for 40 days, each in a group of 24 multiparous Lucerna (Colombian breed) cows. A cross-over design of 8 Latin squares 3 x 3 was used. The variables submitted to analysis were body condition, daily milk production and milk composition. Body condition, milk yield and milk quality were not different but there was a significant decrease in the amount of saturated fatty acid in both experiments while the unsaturated fat increased significantly in experiment 1 and remained stable in experiment 2. Results, such as these have as far as we know, not been reported previously and they provide an approach for the improvement of milk as a "functional food".
Subject(s)
Cattle/physiology , Dietary Fats/administration & dosage , Fatty Acids, Unsaturated/analysis , Fatty Acids/analysis , Lactation/metabolism , Milk Proteins/analysis , Milk/chemistry , Animal Feed , Animal Nutritional Physiological Phenomena , Animals , Cattle/metabolism , Cross-Over Studies , Dietary Supplements , Dose-Response Relationship, Drug , Female , Random AllocationABSTRACT
Se desarrolló un producto alimenticio deshidratado para niños a base de arroz, complementado con soya y frutas para mejorar sus características nutricionales y organolépticas. El proceso consistió en la precocción de los ingredientes y un secado posterior en un deshidratador de tambores. Se obtuvo así un producto final en forma de hojuelas, con un contenido de humedad de 2 a 3%, el cual es de fácil rehidratación cuando se mezcla con un líquido como leche, agua o agua de panela. El panel de catación no detectó diferencia alguna entre las formulaciones con un contenido de soya de: 10, 15 y 20%, respectivamente
