Effects of Knotweed-Enriched Feed on the Blood Characteristics and Fitness of Horses

The aboveground biomass of dry knotweed was administered daily to large groups of young (1- to 3-year-old) stallions of the Czech Warmblood, Czech-Moravian Coldblood and Silesian Norik breeds, fed individually for 4 and 6 months in two successive winter experiments. Their fitness was compared with control groups consisting of equally numerous subgroups comparable in age, breed, body mass and initial blood parameters. The effects of knotweed on the horses’ fitness were evaluated based on changes in blood characteristics. Even if administered in small amounts, 150 g per day, knotweed could (1) increase the thrombocyte numbers, (2) increase the globulin content (thus improving the horses’ immunity, which is desired in large groups of animals), (3) stimulate lipid metabolism in cold-blooded horses and (4) decrease the concentration of cholesterol. The long-lasting effect of knotweed on both the urea and triglyceride–cholesterol ratio presumably reflected, between the two experiments, the temporary protein starvation of horses on pastures with poor quality of grass in a dry summer.

Hepatocyte-Specific Phgdh-Deficient Mice Culminate in Mild Obesity, Insulin Resistance, and Enhanced Vulnerability to Protein Starvation

L-Serine (Ser) is synthesized de novo from 3-phosphoglycerate via the phosphorylated pathway committed by phosphoglycerate dehydrogenase (Phgdh). A previous study reported that feeding a protein-free diet increased the enzymatic activity of Phgdh in the liver and enhanced Ser synthesis in the rat liver. However, the nutritional and physiological functions of Ser synthesis in the liver remain unclear. To clarify the physiological significance of de novo Ser synthesis in the liver, we generated liver hepatocyte-specific Phgdh KO (LKO) mice using an albumin-Cre driver. The LKO mice exhibited a significant gain in body weight compared to Floxed controls at 23 weeks of age and impaired systemic glucose metabolism, which was accompanied by diminished insulin/IGF signaling. Although LKO mice had no apparent defects in steatosis, the molecular signatures of inflammation and stress responses were evident in the liver of LKO mice. Moreover, LKO mice were more vulnerable to protein starvation than the Floxed mice. These observations demonstrate that Phgdh-dependent de novo Ser synthesis in liver hepatocytes contributes to the maintenance of systemic glucose tolerance, suppression of inflammatory response, and resistance to protein starvation.

Influence of soy flour and its processed products on the essential amino acids content in the bees body

Providing bees with benign and sufficient protein feeds is the key to successful beekeeping. Protein feed significantly affects on certain functions of individuals and the vital activity and productivity of the bee colonies. So, as a result of increased consumption of protein feed during the first days of life the supply of proteins in the body significantly increases in young bees, hypopharyngeal glands and other organs become developed, which provides the ability to perform various tasks depending on age and living conditions. Older bees consume protein for tissue renewal with new cells and metabolic processes. Bees raised on low protein feeds become physiologically defective and do not live long. In conditions of protein starvation, brood rearing stops and bees throw larvae out of their cells. The article presents the results of studying the effect of using soy flour and its processed products in bee feeding on the essential amino acids content in their body. It was found that the use of soy peptone in bee feeding contributes to a greater accumulation of essential amino acids in the bees body in different periods of their development, in compared to soy milk, defatted soy flour and roasted soy flour which indicates a higher efficiency of its use as partial substitutes for protein feeds.

Implications of Lewin’s Field Theory on Social Change

During the Second World War, Kurt Lewin was part of a wider research team commissioned by the U.S. Department of Defense to study how dietary habits of American citizens could be changed so as to avoid protein starvation due to the lengthy war efforts. Lewin’s research on food habits can be linked to his earlier studies on social fields. This paper aims to interpret Lewin’s findings on changing dietary habits by using his very own field theory approach, in order to hypothesize how the such findings can be drivers of social change, with the findings being applicable for business management settings as well. Concepts of time and space, as well as ‘simultaneity’ and ‘psychological ecology’ are brought up to discussion in order to back up the purpose of research.

A comparative assessment of the response of three fruit fly species (Diptera: Tephritidae) to a spinosad-based bait: effect of ammonium acetate, female age, and protein hunger

Ammonia-releasing substances are known to play an important role in fruit fly (Diptera: Tephritidae) attraction to food sources, and this information has been exploited for the development of effective synthetic food-based lures and insecticidal baits. In field studies conducted in Hawaii, we examined the behavioural response of wild female oriental fruit fly (Bactrocera dorsalis (Hendel)), melon fly (B. cucurbitae (Coquillett)), and Mediterranean fruit fly (Ceratitis capitata (Wiedemann)) to spinosad-based GF-120 NF Naturalyte Fruit Fly Bait© formulated to contain either 0, 1 or 2% ammonium acetate. Use of visually-attractive yellow bait stations for bait application in the field allowed for proper comparisons among bait formulations. Field cage tests were also conducted to investigate, using a comparative behavioural approach, the effects of female age and protein starvation on the subsequent response of F1 generation B. cucurbitae and B. dorsalis to the same three bait formulations that were evaluated in the field. Our field results indicate a significant positive effect of the presence, regardless of amount, of AA in GF-120 for B. dorsalis and B. cucurbitae. For C. capitata, there was a significant positive linear relationship between the relative amounts of AA in bait and female response. GF-120 with no AA was significantly more attractive to female C. capitata, but not to female B. dorsalis or B. cucurbitae, than the control treatment. Our field cage results indicate that the effects of varying amounts of AA present in GF-120 can be modulated by the physiological stage of the female flies and that the response of female B. cucurbitae to GF-120 was consistently greater than that of B. dorsalis over the various ages and levels of protein starvation regimes evaluated. Results are discussed in light of their applications for effective fruit fly suppression.

Purine and folate metabolism as a potential target of sex-specific nutrient allocation in Drosophila and its implication for lifespan-reproduction tradeoff

The reallocation of metabolic resources is important for survival during periods of limited nutrient intake. This has an influence on diverse physiological processes, including reproduction, repair, and aging. One important aspect of resource allocation is the difference between males and females in response to nutrient stress. We identified several groups of genes that are regulated in a sex-biased manner under complete or protein starvation. These range from expected differences in genes involved in reproductive physiology to those involved in amino acid utilization, sensory perception, immune response, and growth control. A striking difference was observed in purine and the tightly interconnected folate metabolism upon protein starvation. From these results, we conclude that the purine and folate metabolic pathway is a major point of transcriptional regulation during resource allocation and may have relevance for understanding the physiological basis for the observed tradeoff between reproduction and longevity.