Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “domestication selection”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources

Evolution of an instinct under long-term divergent selection for geotaxis in domesticated populations of Drosophila melanogaster.

Long-term divergent selection for geotaxis in lines of Drosophila melanogaster (the fruit fly) is described. After 26 years (600+ generations) of intermittent selection, the mean geotactic scores now remain stable upon relaxed selection, a result suggesting that evolutionary changes have occurred in these lines. Because the stability is not due to genetic fixation (homozygosity) of the lines, it must be due to either close linkage of genes associated with geotaxis (which would not result in enduring change) or the development of new coadapted gene complexes utilizing genes associated with extreme geotaxis expression (which should result in enduring change). Better evidence for the latter hypothesis is obtained from the low, than from the high, line. The notions of coadaptation and genetic homeostasis are considered, as well as the prospective use of the geotaxis lines to study such concepts experimentally. The geotactic behavior expressed in each line is defined as "instinctive": It increases reproductive success and is characteristic of a population.

Animals↗

[The effect of the S1A-receptor agonist ipsapirone on behavior types in wild and domesticated rats].

Selective agonist of 1A subtype of serotonine receptors ipsapirone inhibited manifestation of affective kinds of aggression in wild and domesticated rats. Administration of ipsapirone (10 mg/kg) decreased the number of aggressive attacks of wild and domesticated rats in the test of shock-induced aggression and blocked manifestation of defensive reaction to the experimenter in wild rats. Neophobia in wild rats decreased under the influence of ipsapirone. At the same time ipsapirone did not change mouse-killing behaviour either in wild or in domesticated rats. Probably, 5-HT1A receptors the aggressive regulate reaction, which are parts of the complex of defensive behaviour of the wild animals.

Aggression↗

Professionalizing domesticity: a synthesis of selected nursing historiography.

The 19th century consolidation of the ideology of domesticity and the ideology of professionalism paralleled the evolution of nursing as a formal occupation for women. Efforts to combine these ideologies, which are based on markedly different foundational assumptions, have been central to the history of American nursing. A meaningful understanding of nursing's history necessitates a synthesis of the interpretations generated by individual historians who have studied similar events in nursing's past. Three feminist historians have studied the professionalizing process in nursing. Generated from diverse perspectives and source materials, the work of these historians illuminates the tensions resulting from nursing's efforts to blend the ideologies of domesticity and professionalism and provides insight into the lessons that can be learned from history.

Female↗

Predators select against high growth rates and risk-taking behaviour in domestic trout populations.

Domesticated (farm) salmonid fishes display an increased willingness to accept risk while foraging, and achieve high growth rates not observed in nature. Theory predicts that elevated growth rates in domestic salmonids will result in greater risk-taking to access abundant food, but low survival in the presence of predators. In replicated whole-lake experiments, we observed that domestic trout (selected for high growth rates) took greater risks while foraging and grew faster than a wild strain. However, survival consequences for greater growth rates depended upon the predation environment. Domestic trout experienced greater survival when risk was low, but lower survival when risk was high. This suggests that animals with high intrinsic growth rates are selected against in populations with abundant predators, explaining the absence of such phenotypes in nature. This is, to our knowledge, the first large-scale field experiment to directly test this theory and simultaneously quantify the initial invasibility of domestic salmonid strains that escape into the wild from aquaculture operations, and the ecological conditions affecting their survival.

Animals↗

Likelihood of introducing selected exotic diseases to domestic swine in the continental United States of America through uncooked swill.

To help policy makers determine the need for current regulations (which require cooking of swill prior to feeding to swine), an assessment of the likelihood of exposing domestic swine in the continental United States of America (USA) to selected foreign animal disease agents by feeding uncooked swill was carried out. The hazard was assumed to originate from contraband food items entering the USA and subsequently being discarded in household waste. Such food waste may be collected by licensed waste feeders and fed to swine. This study showed that, of the four diseases studied, the probability of exposure was highest for the classical swine fever (hog cholera) virus. The median annual likelihood of one or more contaminated loads of swill being fed to swine in the continental USA was estimated as follows: classical swine fever virus: 0.063, foot and mouth disease virus: 0.043, swine vesicular disease virus: 0.005, African swine fever virus: 0.005.

African Swine Fever↗

Nasogastric tube feeding at home: a method for adjunctive nutritional support of malnourished patients.

Many patients with chronic diseases develop malnutrition. Force feeding with either enteral tube of parenteral infusions often succeeds in ameliorating this problem in hospitalized patients. However, after discharge many patients are incapable of sustaining adequate dietary intake. As a consequence, malnutrition may persist or recur. The authors' previous experience using nocturnal enteral tube feedings in patients with glycogen storage disease suggested that malnourished patients also might benefit from enteral tube feedings at home. Fourteen undernourished patients selected for domestic enteral tube feedings clearly demonstrated a tolerance, which included adequate gastric emptying, to the infusions during their hospitalization. They ranged in age from 2 months to 68 yr. Infusion pumps delivered the feedings continuously. At home, 12 patients experienced substantial weight gains. Two maintained their weight while they received intensive chemotherapy for malignancies. Except for the two patients with short bowel syndrome, all patients were weaned successfully to oral feedings after 1 to 3 months. The only apparent complication was possible aspiration pneumonia in a patient with neurological dysfunction. This further experience with domestic enteral tube alimentation indicates that selected patients can be managed effectively, safely and economically with nasogastric nutritional support on an outpatient basis.

Adolescent↗

Value of testicular and sperm profiles in optimizing reproductive success: lessons learned from selective breeding programs of domestic and laboratory animals.

The economic potential of the biotechnology of artificial insemination for genetic improvement and disease control was recognized in the United States 50 years ago. To fully exploit this technology in dairy cattle, researchers worked closely with industry to study testicular function, best methods for harvesting and evaluating semen, techniques for preserving and inseminating sperm and finally, methods for mass recording of fertility information. Methods of testicular and semen evaluation have been developed which are highly correlated with other reproductive characteristics, including fertility. This has resulted in an unprecedented opportunity to study experimentally imposed conditions and naturally occurring environmental conditions upon reproductive efficiency in the male. The selection and testing of sires has resulted practically in the elimination of genes which produce lethal or severely depressed performance. The use of one male for the controlled insemination of many females also has facilitated studies on reproductive problems in the female. While less selective breeding programs have been conducted with the rabbit relative to reproductive function, the rabbit has been used extensively as a model for large domestic animals and humans. The rabbit is the smallest laboratory animal which can be trained easily to ejaculate into an artificial vagina and use the semen for insemination. This permits longitudinal and correlative studies to be performed relating testis function and epididymal transport to sperm output, semen quality and fertility. Spermatogenesis of both bulls and rabbits is sensitive to toxicants. The effects can be monitored by testicular biopsy and cytological evaluation of the testis, by semen collection and semen evaluation, and by in vitro and in vivo fertility testing. Gross effects on the testis are detectable in the live animal by measuring testis size and by ultrasound profiles.

Animals↗

Distinct types of selection and genetic architecture shape molecular variation during the domestication of vegetable crops.

Humans select vegetable crops with desirable traits via a complex evolutionary process called domestication, generating a variety of cultivars worldwide. With advances in sequencing technologies, genomic scans for "signatures of selection" are widely used to identify target loci of selection. In the early phases of domestication, humans tended to favor similar sets of phenotypes in diverse crops, resulting in "domestication syndrome" and parallel evolution in multiple species. Subsequently, adaptation to distinct environments or different consumer preferences has diversified crop cultivars. Here, we review molecular and population genetic studies on genes affecting trait evolution during this complex process. We emphasize that, depending on interactions among different types of selection (directional selection within or divergent selection between groups), the genetic architecture of the target trait (Mendelian or polygenic), and the origin of the causal variant (new mutation or standing variation), the resulting molecular patterns of variation can be highly diverse. Situations in which the typical hard selective sweep model could be applied may be limited. Therefore, it is crucial to obtain a thorough understanding of the target species' historical, environmental, and ecological contexts.

Domestication↗

Genetic mapping and QTL analysis of fiber-related traits in cotton ( Gossypium).

Cotton, the leading natural fiber crop, is largely produced by two primary cultivated allotetraploid species known as Upland or American cotton ( Gossypium hirsutum L.) and Pima or Egyptian cotton ( G. barbadense L.). The allotetraploid species diverged from each other and from their diploid progenitors (A or D genome) through selection and domestication after polyploidization. To analyze cotton AD genomes and dissect agronomic traits, we have developed a genetic map in an F2 population derived from interspecific hybrids between G. hirsutum L. cv. Acala-44 and G. barbadense L. cv. Pima S-7. A total of 392 genetic loci, including 333 amplified fragment length polymorphisms (AFLPs), 47 simple sequence repeats (SSRs), and 12 restriction fragment length polymorphisms (RFLPs), were mapped in 42 linkage groups, which span 3,287 cM and cover approximately 70% of the genome. Using chromosomal aneuploid interspecific hybrids and a set of 29 RFLP and SSR framework markers, we assigned 19 linkage groups involving 223 loci to 12 chromosomes. Comparing four pairs of homoeologous chromosomes, we found that with one exception linkage distances in the A-subgenome chromosomes were larger than those in their D-subgenome homoeologues, reflecting higher recombination frequencies and/or larger chromosomes in the A subgenome. Segregation distortion was observed in 30 out of 392 loci mapped in cotton. Moreover, approximately 29% of the RFLPs behaved as dominant loci, which may result from rapid genomic changes. The cotton genetic map was used for quantitative trait loci (QTL) analysis using composite interval mapping and permutation tests. We detected seven QTLs for six fiber-related traits; five of these were distributed among A-subgenome chromosomes, the genome donor of fiber traits. The detection of QTLs in both the A subgenome in this study and the D subgenome in a previous study suggests that fiber-related traits are controlled by the genes in homoeologous genomes, which are subjected to selection and domestication. Some chromosomes contain clusters of QTLs and presumably contribute to the large amount of phenotypic variation that is present for fiber-related traits.

Chromosome Mapping↗

Distribution and density of medium- and short-wavelength selective cones in the domestic pig retina.

The topography of medium (M)- and short (S)-wavelength sensitive cone photoreceptors was studied in the domestic pig retina. Antisera specific for M or S opsin as well as cone photoreceptor proteins arrestin and alpha-transducin were used to label cone types. Retinal wholemounts and their blood vessel patterns were drawn and specific regions removed. The wholemounts were immunocytochemically labelled to detect both M and S cones, and the specific regions labelled to detect S cones. Cones were counted in a 1 mm grid pattern, using the drawings as a guide. Pig retina has a high cone density retinal streak extending across the retina covering the optic disc (OD) and horizontal meridian. Densities in the streak are 20,000-35,000 mm(-2). Two higher peaks occur in the streak, one in temporal retina near the OD (39,000 mm(-2)) and the other in nasal retina 5-7 mm from the OD (40,500 mm(-2)). The lowest cone density is in far peripheral inferior retina (7000 mm(-2)). The total number of cones in pig retina is 17-20 million. Both types of cones are found throughout the retina, with S cone percentages ranging from 7.4 to 17.5% in no consistent topographical pattern. S cones have an irregular local distribution which can vary from a regular hexagonal pattern to small clusters of adjacent S cones to small areas lacking S cones. Double-label immunocytochemistry found that virtually all S cone outer segments (OS) contain some M opsin. M cone OS do not label at detectible levels for S opsin. Domestic pig retina is widely available, large, has a high cone density and has two types of cones. This tissue should be an excellent source for biochemical analysis of cone proteins, and for in vitro approaches to understanding cone survival factors.

Animals↗

Withdrawal of zinc oxide-containing diets from mature, female domestic fowl: effects on selected tissue mineral contents.

1. Two hundred and sixteen laying hens of two strains were given diets containing ZnO to provide 0, 0.5, 0.75, 1.00, 1.25, 1.50, 2.00, 3.00 or 4.00 g added Zn/kg. These diets were offered ad libitum for 5 consecutive 28-d periods. All hens were subsequently offered the control diet with no added ZnO for 5 weeks. 2. Four hens from each treatment were killed 0, 1 and 5 weeks after substitution of the ZnO-supplemented diets by the control diet. 3. Dietary addition of ZnO significantly increased liver, kidneys, pancreas and gizzard Zn contents but this effect was rapidly reversed on removal of the ZnO-containing diets. 4. Hepatic and renal Fe contents were significantly depressed by dietary ZnO but after substitution of these diets by the control diet the values were comparable to that of the controls. 5. Liver Cu content declined significantly as dietary ZnO concentration increased but there was a return towards normal after ZnO withdrawal. Renal, pancreatic and gizzard Cu contents showed quadratic responses to added ZnO. 6. After ZnO withdrawal for 5 weeks, pancreas Cu contents declined linearly, whereas renal and gizzard Cu values were similar for all treatments. 7. Overall the long-term feeding of ZnO-supplemented diets followed by a period of withdrawal of the ZnO supplement had no detrimental effects on tissue mineral contents.

Animals↗

Selection experiment for increased egg production under 23 H and 24 H light-dark cycles in the domestic fowl.

A selection experiment was conducted for increased rate of lay under 23-h (23 HS line) and 24-h (24 HS line) light-dark cycles over 5 generations. In generation 5, rate of lay was higher in the 23 HS line than in the 24 HS line, and the proportion of hens with mean intra-sequence intervals of less than 24 h in the 23 HS line increased to 88% in the generation 5 from 15% in the base generation. The realised heritability for rate of lay was 0.25 plus/minus 0.04 in the 23 HS line and 0.15 plus/minus 0.05 in the 24 HS line. Egg weight and shell weight decreased in both lines, and the decrease in the proportion of shell was larger in the 23 HS line than in the 24 line. It is suggested that a regimen of 23 h light and dark may be an effective environment for selection to improve the laying performance of a population approaching a plateau for egg production.

Animals↗

Respiratory responses of domestic fowl to hyperthermia following selective air sac occlusions.

Ventilation together with blood and respiratory gas tensions were measured in adult domestic fowl under normothermic and hyperthermic conditions, following bilateral occlusion of the cranial and caudal thoracic air sacs (series I) or the cranial and caudal thoracic plus the abdominal air sacs (series II). Series I birds showed no significant differences from controls. Both control and experimental animals displayed a typical thermal polypnoea combined with mild hypocapnaemia. A larger drop in PCO2 was demonstrated in the clavicular sac than in the blood, possibly indicating partial failure of inspiratory valving at the ventrobronchi. However, there was no evidence of any effect of thoracic air sac occlusion on inspiratory airflow valving in the palaeopulmo. Series II birds were strongly hypercapnaemic/hypoxaemic in normothermic conditions, with a normal minute volume, but a faster, shallower breathing pattern. During hyperthermia they increased minute ventilation 3-fold, as in control animals, and blood gas tensions were almost restored to normal. Again, there was no evidence that experimental reduction in air sac capacity, in this case up to 70% of the total, had any effect on inspiratory airflow valving in the palaeopulmo, although inevitably in this case airflow in the neopulmo was abolished.

Air Sacs↗