Change in genetic size of small-closed populations: Lessons from a domestic mammal population

The aim of this study was to monitor changes in genetic size of a small-closed population of Iranian Zandi sheep, by using pedigree information from animals born between 1991 and 2005. The genetic size was assessed by using measures based on the probability of identity-by-descend of genes (coancestry, f, and effective population size, Ne ), as well as measures based on probability of gene origin (effective number of founders, fe , effective number of founder genomes, fg , and effective number of non-founder genomes, fne ). Average coancestry, or the degree of genetic similarity of individuals, increased from 0.81% to 1.44% during the period 1993 to 2005, at the same time that Ne decreased from 263 to 93. The observed trend for fe was irregular throughout the experiment in a way that fe was 68, 87, 77, 92, and 80 in 1993, 1996, 1999, 2002, and 2005, respectively. Simultaneously, fg , the most informative effective number, decreased from 61 to 35. The index of genetic diversity (GD) which was obtained from estimates of fg , decreased about 2% throughout the period studied. In addition, a noticeable reduction was observed in the estimates of fne from 595 in 1993 to 61 in 2005. The higher than 1 ratio of fe to fg indicated the presence of bottlenecks and genetic drift in the development of this population of Zandi sheep. From 1993 to 1999, fne was much higher than fe , thereby indicating that with respect to loss of genetic diversity, the unequal contribution of founders was more important than the random genetic drift in non-founder generations. Subsequently, random genetic drift in non-founder generations was the major reason for fe > fne . The minimization of average coancestry in new reproductive individuals was recommended as a means of preserving the population against a further loss in genetic diversity

Salt restriction in kidney disease—a missed therapeutic opportunity?

The importance of salt restriction in the treatment of patients with renal disease has remained highly controversial. In the following we marshal the current evidence that salt plays a definite role in the genesis of hypertension and target organ damage, point to practical problems of salt restriction, and report on novel pathomechanisms of how salt affects blood pressure and causes target organ damage

Riverine drift communities during larval fish dispersal over multiple recruitment years

Predation during the downstream dispersal of larval stages represents a major recruitment bottleneck for fish populations. The co-occurrence of other organisms in river drift may reduce predation, but our knowledge of the factors influencing the composition and abundance of drift communities during post-hatch dispersal of larval fish remain limited. A multi-year (2011-2018) study was conducted to investigate abiotic factors influencing drift communities during larval lake sturgeon (Acipenser fulvescens) dispersal in the Upper Black River (Cheboygan, MI, USA). Cumulative water temperature was a strong predictor of drift for larval lake sturgeon, suckers (Catostomidae) and macroinvertebrates, with reduced macroinvertebrate drift during lunar phases with higher lunar illumination. Nights with a new moon had on average, three times the drifting macroinvertebrate biomass as nights during a full moon, with Heptageniidae and Isonychiidae displaying higher abundances during lower light conditions. Favorable conditions for other taxa to reduce larval lake sturgeon predation through predator swamping were common, though variability in timing (overlap between drifting taxa), biomass, and abundances likely alters the strength of such effects among years. A better understanding of the conditions influencing drifting communities during larval fish dispersal may assist in predicting larval mortality and year-class strength for managed fish populations

Game-Based Learning and Lifelong Learning for Tourist Operators

Today\u2019s workplace challenges are based on the belief that the group can face current challenges better using collaboration than any individual can by yourself. This belief has prompted social solutions, such as communities of practice or knowledge and social peer-learning. Learning by playing a game is a very old method that is still applied in various contexts. Mainly in social-learning activities, the learner\u2019s motivation is crucial to program success. Games are fun and immersive by nature. By using games in lifelong learning contexts, it is possible to deliver continuous high attention and engagement for substantial learning