Effects of a postbiotic, with and without a saponin-based product, on turkey performance.

Modern poultry production relies on an ability to prevent and mitigate challenges to bird health, while maintaining a productive bird. A number of different classes of biologics-based feed additives exist, and many have been tested individually for their impacts on poultry health and performance. Fewer studies have examined the combinations of different classes of products. In this study, we examined the use of a well-established postbiotic feed additive (Original XPC, Diamond V) on turkey performance, with and without the addition of a proprietary saponin-based feed additive. This was accomplished in an 18-wk pen trial utilizing 22 pen replicates per treatment across 3 treatments (control, postbiotic, and postbiotic plus saponin). Significant differences in body weight were identified at wk 12 and 15 of age, with the postbiotic plus saponin treatment group resulting in heavier birds at both timepoints. Significant differences in feed conversion ratio were observed from 0 to 18 wk of age, with the postbiotic alone having improved FCR compared with the control group. No significant differences were observed for livability or feed intake. This study demonstrates that a combination of a postbiotic plus saponin may exert additive effects on the growth of the turkey.

AGEMAP: a gene expression database for aging in mice.

We present the AGEMAP (Atlas of Gene Expression in Mouse Aging Project) gene expression database, which is a resource that catalogs changes in gene expression as a function of age in mice. The AGEMAP database includes expression changes for 8,932 genes in 16 tissues as a function of age. We found great heterogeneity in the amount of transcriptional changes with age in different tissues. Some tissues displayed large transcriptional differences in old mice, suggesting that these tissues may contribute strongly to organismal decline. Other tissues showed few or no changes in expression with age, indicating strong levels of homeostasis throughout life. Based on the pattern of age-related transcriptional changes, we found that tissues could be classified into one of three aging processes: (1) a pattern common to neural tissues, (2) a pattern for vascular tissues, and (3) a pattern for steroid-responsive tissues. We observed that different tissues age in a coordinated fashion in individual mice, such that certain mice exhibit rapid aging, whereas others exhibit slow aging for multiple tissues. Finally, we compared the transcriptional profiles for aging in mice to those from humans, flies, and worms. We found that genes involved in the electron transport chain show common age regulation in all four species, indicating that these genes may be exceptionally good markers of aging. However, we saw no overall correlation of age regulation between mice and humans, suggesting that aging processes in mice and humans may be fundamentally different.

Transcriptome analysis of age-, gender- and diet-associated changes in murine thymus.

The loss of thymic function with age may be due to diminished numbers of T-cell progenitors and the loss of critical mediators within the thymic microenvironment. To assess the molecular changes associated with this loss, we examined transcriptomes of progressively aging mouse thymi, of different sexes and on caloric-restricted (CR) vs. ad libitum (AL) diets. Genes involved in various biological and molecular processes including transcriptional regulators, stress response, inflammation and immune function significantly changed during thymic aging. These differences depended on variables such as sex and diet. Interestingly, many changes associated with thymic aging are either muted or almost completely reversed in mice on caloric-restricted diets. These studies provide valuable insight into the molecular mechanisms associated with thymic aging and emphasize the need to account for biological variables such as sex and diet when elucidating the genomic correlates that influence the molecular pathways responsible for thymic involution.