Search Results (3)

Harvester ants often selectively forage seeds, causing these ants to be viewed as pests in agricultural areas where they may forage on crop seeds. While little research has been done on harvester ant preferences for cover crop seeds, grower observations in the Lower Rio Grande Valley (LRGV) suggest that ants may remove these seeds before germination. We examined red harvester ant (Pogonomyrmex barbatus F. Smith) preferences for cover crop seeds (fescue, oat, sunn hemp, radish, vetch, and wheatgrass) and the effects of a commonly used bacterial seed inoculant. We evaluated relative preferences using seed depots presented to colonies with no prior exposure to the selected seeds or inoculants. After 24 h, ants had removed oat and radish seeds at the same rate as the preferred wheatgrass control. Fescue, sunn hemp, and vetch seeds were less preferred. The bacterial inoculation of wheatgrass and radish seeds did not alter the removal rates. Further, ant removal of seeds in both trials was dependent on the month and temperature, indicating potential interactions of colony activity levels, availability of seeds in the seed bank, and the intensity of cover crop seed removal. Together, these data indicate that harvester ant foraging preferences and seasonal activity should be considered to help mitigate potential ant predation of cover crops via planting less preferred seeds and at times of lower ant foraging intensity. Full article

Grain legumes, which are commonly referred to as pulses, are staple foods in many parts of the world, but are infrequently consumed in most economically developed countries where the obesity pandemic is prominent. However, even in low pulse consuming countries such as the United States, there are sub-groups of individuals who consume large amounts of pulses. Systematic reviews of population studies indicate that pulse consumers have a lower risk for developing obesity. To determine whether these population-based findings could be modeled in preclinical systems in which such findings can be deconstructed, we used rat and mouse models of dietary induced obesity and reported that lipid accumulation was inhibited. In this study, we examined the relationship between inhibition of fat accumulation and changes in the gut associated microbiome in male C57BL/6 mice fed either a high fat diet with casein as the protein source or that diet formulation in which one of four pulses (chickpea, common bean, dry pea, or lentil) was substituted to provide 70% dietary protein with the remainder provided by casein. The seeds of each pulse were soaked, cooked, and then freeze-dried and milled; the resulting powder was used for diet formulation. Mice were ad libitum fed over the 17-week duration of the feeding trial. Cecal content was obtained at necropsy and immediately snap frozen in liquid nitrogen. Extracted genomic DNA was processed for 16s rRNA sequencing on an Illumina system. Significant differences were observed between each pulse and the high fat control diet in microbial phylogenetic diversity (p < 0.001) and accumulation of lipid in adipose depots (p < 0.01). Differences among pulses were also observed in both metrics. Microbiome alpha and beta diversity metrics, differences in abundance for each detected taxon among treatment groups, and their relationships to changes in lipid accumulation in adipose storage depots are reported. Full article

A dose of proanthocyanidins with satiating properties proved to be able to limit body weight increase several weeks after administration under exposure to a cafeteria diet. Here we describe some of the molecular targets and the duration of the effects. We treated rats with 500 mg grape seed proanthocyanidin extract (GSPE)/kg BW for ten days. Seven or seventeen weeks after the last GSPE dose, while animals were on a cafeteria diet, we used reverse transcriptase-polymerase chain reaction (RT-PCR) to measure the mRNA of the key energy metabolism enzymes from the liver, adipose depots and muscle. We found that a reduction in the expression of adipose Lpl might explain the lower amount of adipose tissue in rats seven weeks after the last GSPE dose. The liver showed increased expression of Cpt1a and Hmgs2 together with a reduction in Fasn and Dgat2. In addition, muscle showed a higher fatty oxidation (Oxct1 and Cpt1b mRNA). However, after seventeen weeks, there was a completely different gene expression pattern. At the conclusion of the study, seven weeks after the last GSPE administration there was a limitation in adipose accrual that might be mediated by an inhibition of the gene expression of the adipose tissue Lpl. Concomitantly there was an increase in fatty acid oxidation in liver and muscle. Full article