Food and reproduction of wild house mice. 2. A field experiment to examine the effect of food availability and food quality on breeding in spring

We performed supplemental feeding experiments during three breeding seasons of the Blue Tit (Parus caeruleus L.) in order to establish the importance of food in reproductive timing. In particular, we addressed the question of why the response to supplemental food is restricted to 3—6 d in many bird species. Supplemental food advanced the start of egg—laying in all three breeding seasons. The mean difference between fed and control pairs was 4 d in two years and 6 d in another. The amount and quality of the supplemental food used in the experiment were not limiting, since pairs receiving a further increase in amount and quality of food did not start laying earlier than pairs with a standard feeding regime. The amount of food that was consumed increased during the period from 15 d before egg formation until the beginning of egg formation and then remained at a high utilization rate until clutch completion. Although fed pairs, on average, started egg—laying earlier than control pairs, the earliest control females started to lay eggs as early as the first females. Fed pairs were also relatively late in a year when control pairs were late. In 1992, fed pairs did not produce larger clutches or more fledglings, but had nestlings with lower mass at 13 d post—hatching than those of control pairs. Analysis at the territory level revealed that supplemental food affected laying date to a greater extent in low—quality territories, in which laying could be advanced by up to 9—10 d, compared to high—quality territories in which laying was not advanced at all. We conclude that laying date in most Blue Tit females is limited by low food supply early in spring, but some females, occupying high—quality territories, will not advance laying in response to food. Thus, above a certain critical limit, laying date is unrelated to food supply, and birds use other cues in their decision to commence breeding. Such cues are probably also responsible for the between—year variation in laying dates of food—supplemented pairs, since these were provided with the same amount of food during the different years.

Food quantity and quality are highly variable in natural systems. Therefore, their interplay and the associated effects on consumer population growth are important for predator–prey interactions and community dynamics. Experiments in which consumers were exposed to elemental nutrient limitations along food quantity gradients suggest that food quality effects on consumer performance are relevant only at high food quantities. However, elemental nutrients act differently on physiological processes than biochemical nutrients. So far, the interactive effects of food quantity and biochemical compounds on consumer performance have been insufficiently studied. We studied interactive effects of food quantity and biochemical food quality on population growth, including fecundity and survival, of the freshwater rotifer Brachionus calyciflorus. We hypothesised that these life history traits are differently affected by the availability of biochemical nutrients and that food quality effects gain importance with increasing food quantity. In a first experiment, we established food quantity and quality gradients by providing rotifers with different concentrations of a low‐quality food, the sterol‐free cyanobacterium Synechococcus elongatus, supplemented with increasing amounts of cholesterol. In a second experiment, food quantity and quality gradients were established by providing different proportions of two prey species differing in biochemical food quality, i.e. S. elongatus and the lipid‐rich alga Nannochloropsis limnetica, at different total food concentrations. We found that the effects of cholesterol supplementation on population growth increased with increasing food quantity. This interactive effect on population growth was mainly due to food quality effects on fecundity, as effects on survival remained constant along the food quantity gradient. In contrast, when feeding on the mixed algal diet, the food quality effect associated with increasing the proportion of the high‐quality alga did not change along the food quantity gradient. The data on survival and fecundity demonstrate the missing interactive effect of food quantity and quality on population growth, as both traits were oppositely affected. Survival was affected by food quality primarily at low food quantity, whereas food quality effects on fecundity were stronger at high food quantity. Our results highlight the significance of essential biochemicals in mediating the interactive effects of food quantity and quality on population growth. The interplay between food quantity and biochemical food quality limitation seems to influence resource allocation patterns in order to optimise survival or reproduction, which may strongly affect population dynamics in variable environments. As opposed to exploring the function of a single nutrient via supplementation, using algae mixtures allowed us to assess food quality effects on consumer performance in a more natural context by taking potential interactive effects of multiple co‐limiting nutrients into account.

Upland rice and dry-cultivated paddy rice have been attracted more and more attention because of limited water re- sources in China. Researches on interaction between water and nitrogen supplies for crop resistance to drought stress has become a hot topic in crop physiology. However, the information linking to the effect of nitrogen nutrition on grain quality of upland rice and paddy rice under different cultivation methods is unavailable. The objective of this study was to evaluate the difference be- tween upland rice and paddy rice and interaction between cultivation methods and N levels. One upland rice cultivar Zhonghan 3 (japonica) and one paddy rice cultivar Yangjing 9538 (japonica) were grown under either moist cultivation (MC, control) or bare dry-cultivation (DC) conditions, with three N levels, low amount of nitrogen (LN, 100 kg ha-1), normal amount of nitrogen (NN, 100 kg ha-1), and high amount of nitrogen (HN, 300 kg ha-1). The results showed that, compared with NN, the grain yield under HN was lower for both upland and paddy rice under DC and for paddy rice under MC, whereas it was higher for upland rice under MC. Under both DC and MC, the percentage of chalky grains and the chalkiness of upland rice were increased under NN and reduced under HN. With the increase in N levels, amylose content was reduced and protein content was increased for both upland and paddy rice. However, the percentage of chalky grains and the chalkiness of paddy rice was decreased under DC and increased under MC. Breakdown viscosity was the highest and setback viscosity was the lowest for upland rice under NN and for paddy rice under LN. The bare dry cultivation can improve appearance quality and nutrient quality for upland rice. There was no significant difference in other rice quality indices between upland rice and paddy rice under DC. Compared with paddy rice, upland rice showed better nutrient quality and poor appearance quality and cooking quality. The correlation coefficient between cooking and nutrient quality and leaf nitrogen content was smaller for upland rice than for paddy rice. The results suggest that the response to cultivation methods and nitrogen levels varies largely between upland rice and paddy rice. The approaches to increase grain yield and grain quality for both paddy and upland rice were discussed.

A field experiment, with a 22 factorial design, was conducted on sixteen trapping grids to test the effects of food quality (protein content) and reduced population density on the breeding performance of house mice (Mus musculus L.). The experiment was conducted in a rice field in New South Wales, Australia, in autumn (March-June) 1983, when there was an abundant supply of rice grain, so food energy was not a limiting factor for breeding. Protein was supplemented by ad libitum provision of oats and sunflower seeds. An increase in the protein content of the diet from 8% to 11% was associated with a significant increase in the proportion of females breeding. There was no breeding response to culling of females with head-body length ' 75 mm plus males < 82 mm, nor to interaction of culling x food-quality. The absence of a culling effect is discussed in relation to seasonal conditions and a previously postulated food-quality, spacing-behaviour hypothesis of mouse-plague formation.

It is unclear whether stingless bees in the genus Melipona (Hymenoptera, Apidae, Meliponini) can reli- ably encode the distance to a food source through recruitment sounds produced inside the nest, in part because the sound features correlated with distance also vary with food quality. We therefore trained marked foragers of two species, Melipona mandacaia and M. bicolor, to feeders at different distances and to different sucrose concentrations at the same distance. In both species, foragers successfully recruited to a rich 2.5-m food source and produced pulsed recruitment sounds in which pulse duration was significantly and positively correlated with distance to the rich food source. When returning from poorer food sources (0.6-1.5 m), foragers of both species decreased sound production, producing shorter sound pulses and longer sound interpulses than they did for 2.5 m food located at the same distance. Thus the temporal structure of M. mandacaia and M. bicolor recruitment sounds varies with distance and food quality. However, nestmates were not recruited by performances for poorer food sources (0.6-1.5 m), whose sucrose concentration was sufficiently low to affect recruitment sounds. Surprisingly, the interphase (the time between behavioral phases that communicate location) also in- creases with decreasing food quality in the closely related honeybees (Apis), suggesting a potential homology in the effect of food quality on the recruitment systems of Apis and Melipona. We explore the evolutionary implications of these similarities.

The diet and breeding seasons of house mice, Mus musculus L., were monitored for 16 months in six habitats on two cereal farms: fields of barley, wheat, sorghum and rice stubble, and contour banks in rice fields, and channel banks. In all habitats mice were mainly granivorous. Because of rotational cropping and irrigation, seeds were available in different habitats in each season and this was reflected in the diets. Cereal grains spilt at harvest and other stale seeds were the main food in the nonbreeding season. It is proposed that the low quality of this food limited breeding. When milk-ripe grass seeds became available, mice switched to this fresh food, and started breeding about 1 month later. The onset of breeding was asynchronous between different habitats; this suggests that time of onset of breeding was determined by availability of food.

We investigated the interaction of intergenerational temperature and food quality change on the fitness of two species of Daphnia, a freshwater keystone herbivore. The effect of a change in temperature (15°C vs. 20°C) and food quality (Cryptomonas sp. as high‐quality food vs. Chlamydomonas sp. as relatively low‐quality food) on juvenile growth rate and clutch size of Daphnia magna and Daphnia pulex was measured in 16 combinations of maternal and offspring environments in standardized growth assays. Both species showed similar responses. The positive effect of food quality on growth rate and clutch size was stronger if the maternal diet was of low quality. High maternal diet quality generally increased growth rate and reproduction, especially if the offspring diet was of low quality. The maximum fitness was attained by animals acclimated at 15°C and growing at 20°C, combining the faster growth rate at warm assay temperature and bigger clutch size of cold‐acclimated animals. Intergenerational temperature regime had a strong influence on the effects of maternal and offspring food quality. Good maternal food quality was more important for fitness under less favorable temperature conditions. Low offspring food quality was more detrimental to fitness in animals experiencing temperature change between maternal acclimation and growth assay and less so under constant temperature conditions. Intergenerational changes in temperature and the maternal effects of food quality strongly affect the dietary requirements of these organisms. Hence, extrapolation from studies conducted under constant temperature conditions may seriously underestimate dietary constraints in natural environments.

In order to calibrate carrying capacity models, investigations were conducted into the effects of food concentration and food quality on the feeding rates of small (25–50 mm), medium (60–85 mm) and large (90–115 mm) Greenshell mussels (Perna canaliculus). Experimental diets varying from 3.3 to 6.0 μg l−1 chlorophyll a concentration and 12–25% organic content were fed to mussels housed in individual flow through chambers. Not surprisingly, this study found that the main factor affecting feeding rates is mussel size. Small mussels were observed to maintain a constant filtration rate of approximately 20 mg h−1 irrespective of food concentration or quality, whereas mussels of greater than 60 mm length had more variable filtration rates between 30 and 80 mg h−1. The filtration rates of these large mussels were also observed to increase positively with organic content, and showed no sign of levelling out, even at the highest organic content tested (25%). Highest rejection rates (50–70 mg h−1) were observed when the organic content of the available seston was low, suggesting that P. canaliculus are able to selectively reject organic material, thereby organically enriching their diet. It appears that the organic content of the seston is the primary determinant of the net efficiency with which food is selected from the available seston by the mussel. The present study shows that P. canaliculus of all sizes are capable of adapting their feeding behaviour to compensate for changes in the food supply, which may occur over relatively short time periods, in the culture environment.

Meiotic recombination is an important evolutionary force and an essential meiotic process. In many species, recombination events concentrate into hotspots defined by the site-specific binding of PRMD9. Rapid evolution of Prdm9's zinc finger DNA-binding array leads to remarkably abrupt shifts in the genomic distribution of hotspots between species, but the question of how Prdm9 allelic variation shapes the landscape of recombination between populations remains less well understood. Wild house mice (Mus musculus) harbor exceptional Prdm9 diversity, with >150 alleles identified to date, and pose a particularly powerful system for addressing this open question. We employed a coalescent-based approach to construct broad- and fine-scale sex-averaged recombination maps from contemporary patterns of linkage disequilibrium in nine geographically isolated wild house mouse populations, including multiple populations from each of three subspecies. Comparing maps between wild mouse populations and subspecies reveals several themes. First, we report weak fine- and broad-scale recombination map conservation across subspecies and populations, with genetic divergence offering no clear prediction for recombination map divergence. Second, most hotspots are unique to one population, an outcome consistent with minimal sharing of Prdm9 alleles between surveyed populations. Finally, by contrasting aggregate hotspot activity on the X versus autosomes, we uncover evidence for population-specific differences in the degree and direction of sex dimorphism for recombination. Overall, our findings illuminate the variability of both the broad- and fine-scale recombination landscape in M. musculus and underscore the functional impact of Prdm9 allelic variation in wild mouse populations.

Species interactions are often context dependent, where outcomes vary in response to one or more environmental factors. It remains unclear how abiotic conditions like temperature combine with biotic factors such as consumer density or food quality to affect resource availability or influence species interactions. Using the large grasshopper Melanoplus bivittatus (Say) and a common wolf spider [Rabidosa rabida (Walkenaer)], we conducted manipulative field experiments in tallgrass prairie to examine how spider-grasshopper interactions respond to manipulations of temperature, grasshopper density, and food quality. Grasshopper survival was density dependent, as were the effects of spider presence and food quality in context-dependent ways. In high grasshopper density treatments, predation resulted in increased grasshopper survival, likely as a result of reduced intraspecific competition in the presence of spiders. Spiders had no effect on grasshopper survival when grasshoppers were stocked at low densities. Effects of the experimental treatments were often interdependent so that effects were only observed when examined together with other treatments. The occurrence of trophic cascades was context dependent, where the effects of food quality and spider presence varied with temperature under high-density treatments. Temperature weakly affected the impact of spider presence on M. bivittatus survivorship when all treatments were considered simultaneously, but different context-dependent responses to spider presence and food quality were observed among the three temperature treatments under high-density conditions. Our results indicate that context-dependent species interactions are common and highlight the importance of understanding how key biotic and abiotic factors combine to influence species interactions.

Context. In New Zealand, the aerial application of toxic baits containing sodium fluoroacetate (1080) can consistently achieve significant reductions in populations of multiple vertebrate pest species including brushtail possums (Trichosurus vulpecula), ship rats (Rattus rattus) and stoats (Mustela erminea). Reductions in house mouse (Mus musculus) populations by 1080 baiting appear less consistent, possibly due to low acceptance of 1080 bait by mice in field conditions. Aims. We tested the effect of pre-feeding and 1080 concentration on the acceptance of pellet food by mice. Methods. Wild-caught mice were individually housed and presented with a series of two-choice laboratory feeding tests, using estimates of the daily amount eaten to indicate relative acceptance of different types of pellet food. Key results. Pre-feeding mice on non-toxic food did not increase their subsequent acceptance of the same food containing 0.15% 1080. Mice showed low acceptance of food containing 0.08 and 0.15% 1080 (by weight), with similar mortality (25%). Acceptance of food containing 1.5% 1080 was also very low in comparison with non-toxic food, although mortality in mice was higher (~66%). In comparison with other concentrations, mice ate comparatively more of food containing 0.001% 1080 with no mortality, although the non-toxic food was still significantly favoured. Presentation of a choice between non-toxic food and food containing 0.08, 0.15 or 1.5% 1080 to mice was followed by a significant decrease in average total daily food intake over the following 2 days. In surviving mice this ‘drop feed’ effect was followed by an increase in average daily intake of non-toxic food over the next 3 days until normal daily intake levels were again reached. Conclusions. We suggest that wild mice can rapidly identify food containing 1080 and subsequently will avoid it. Implications. This feeding response partly explains the variable success of 1080 baiting operations against wild mouse populations (M. musculus) in New Zealand.

In field populations of house mice (Mus musculus) seasonal and year-to-year variation in numbers are usually attributed to variations in the availability of food and home sites, and the effectiveness of agents affecting life-spans. Variations in numbers similar to those observed in the field also occurred in a mouse population housed in an out-door pen in which the number of home sites was limited but food supplies were abundant but these variations were due to seasonal variations in the effectiveness of self-regulating mechanisms. To examine the effects of food supply, amount of shelter and of one agent affecting life-spans (culling) on mouse numbers in confined populations, numbers were monitored in a control pen and in three experimental pens in which food supply was halved, home sites were doubled and mice were culled at four weekly intervals. The effects of the treatments were followed for four and a half years. Although supplies of food and shelter remained constant throughout the study, mouse numbers in the control pen were high in summer and low in winter and the heights of the summer peaks varied from year to year. Halving the amount of food available reduced the mean size of the population by 37% by reducing numbers in summer. Doubling the number of home sites increased mean size by 13% by increasing numbers in winter. Culling about 60% of the mice at monthly intervals reduced mean size by 13%. All experimental treatments reduced the amplitude of the seasonal fluctuations and between-year differences in the heights of the summer peaks. In the control pen more young were recruited in summer than in winter. Halving the amount of food available reduced the numbers recruited in summer by increasing the number of pups dying between birth and weaning. Doubling the number of home sites and culling increased the numbers recruited in spring, summer and autumn by increasing the number of females breeding. These increases were associated with decreases in the mean sizes of the populations living in the home sites. In the control pen the mean life-spans of the males and females which survived until they were weaned were 4.9 and 6.4 months respectively. Halving the amount of food available had no effect on mean life-spans but doubling the number of home sites reduced them significantly. It was concluded that self-regulating mechanisms continued to affect numbers in all three experimental pens but that numbers were also affected by the availability of food in summer in both the pen in which food supplies were reduced and the pen in which the number of shelters was doubled. It was also concluded that although mouse numbers were reduced by culling, the indirect effects of this treatment on recruitment tended to compensate for its direct effect on numbers.

1. Maternal effects have been suggested to function as a mechanism for transgenerational plasticity, in which the environment experienced by the mother is translated into the phenotype of the offspring. In birds and other oviparous vertebrates where early development is within the egg, mothers may be able to improve the viability prospects of their offspring at hatching by priming eggs with immunological and nutritional components. 2. We studied how resource availability affects maternal investment in offspring by feeding Ural owl (Strix uralensis, Pall.) females prior to egg-laying in 3 years of dramatically different natural food conditions. 3. Supplementary feeding prior to laying increased body mass and the level of Igs of females measured at clutch completion. Supplementary fed Ural owl females laid larger eggs than control females, and had offspring with higher levels of Igs at hatching compared to offspring of control females. 4. We found variation in maternal allocation of resources to the eggs in response to environmental conditions: during a year of rapidly declining food abundance, maternal Igs in hatchlings were higher, whereas egg size was smaller compared to years with a more stable food supply. 5. Egg size had a positive effect on offspring body mass at fledging, whereas Igs at hatching did not affect Igs at fledging. 6. We conclude that maternal body condition and maternal Igs, as well as hatchling Igs and egg size are limited by food resources during egg production. Hatchlings rely on maternally derived Igs and, hence, our results suggest that mothers with high levels of Igs passively transfer higher Igs levels to their eggs instead of active manipulation of Igs levels in eggs. Ural owl egg size appears to be highly sensitive to short-term changes in food abundance, with important consequences for nestling growth.

Customer satisfaction covers both tangible and intangible elements of product offerings. In these product offerings, perceived service quality and value are found to be significant in customer satisfaction in service firms e.g. coffee shops, restaurants and hotels as being service providers. Therefore, the overall aim of this study was to specifically investigate the effects of food quality, service quality and ambience quality on customer satisfaction and loyalty in a chain coffee shop. With this main aim of the study, a questionnaire survey was used to collect data from the customers of a chain coffee shop in Batman, Turkey. The questionnaire consisted of two main parts. The first part required the demographic information about the coffee shop customers. The second part of the questionnaire had the questions about the qualities of food, service and ambience. A seven-point Likert scale with items comprising the survey questions was presented to the coffee shop customers, where 1 represented “strongly disagree” and 7 represented “strongly agree”. With this questionnaire, the study survey produced 404 questionnaires from the sample from March 15 2019 to May 15 2019. For the data analysis, the reliability of the study was first tested. Then, the exploratory factor analysis and regression analysis were applied to find out the effects of food quality, service quality and ambience quality on customer satisfaction and loyalty. The findings presented that food quality (p: ,000 and β: ,383), service quality (p: ,000 and β: ,240) and ambience quality (p: ,000 and β: ,215) had a significant and positive effect on customer satisfaction of the coffee shop customers. However, customer satisfaction did not create any loyalty on the coffee shop customers.

:We studied the effects of food supplementation on 16 bank vole populations in spring. We manipulated food quantity and quality in eight populations that were enclosed and eight other populations that were free-ranging on forest grids. The enclosed populations received large amounts of sunflower seeds, as high-quality food (four enclosures) or barley seeds, as low-quality food (four enclosures). Four of the open populations were supplemented with small amounts of spruce seeds, and four served as non-supplemented controls. Effects of differential food quantity and quality on overwintering weight of individual females and on spring litters were monitored by live-trapping. Pregnant females were removed to the laboratory for parturition and to record pup number and weight. Female body mass at the onset of breeding was highest in enclosures with high-quality food. Females from both enclosure treatments with a large quantity of food were heavier than females from open grids. The litters from enclosures supplemented with high-quality food tended to be one pup larger and grew faster than those from the low-quality food enclosures. Litter size of females of the non-supplemented forest plots did not differ from that of the spruce-seed-supplemented plots or from the enclosure females. In general, quantity of winter food may affect female body weight in spring, but quality of food appeared to have a positive effect on litter size and early growth of pups.