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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The Investigation of Food Neophobia and Bitterness Sensitivity on Food Preference in Familiar and Unfamiliar Fruits and Vegetables in California Elementary Schools

Handley, Maria 01 December 2018 (has links) (PDF)
The goal of this study was to understand the relationship between food neophobia and bitterness in consumer liking. Fruit and vegetable consumption is necessary for elementary school children to build healthy habits. Free and reduced lunch programs (FRL) in schools provide nutritional opportunities to students. Bitterness sensitivity and food neophobia were examined as separate drivers of liking in acceptance testing (n=161, ages 6-12) from two local elementary schools (high and low %FRL). The food neophobia scale and the fruit and vegetable neophobia instrument (FNVI) were used to determine food neophobia. FNVI scores distinguished consumers in hierarchical cluster analysis of overall liking. FVNI scores correlated to texture liking and flavor liking in familiar and unfamiliar fruits and vegetables. Non-bitter sensitive participants unexpectedly exhibited more neophobia than bitter sensitive participants. Neophobic participants liked familiar products more than unfamiliar products. Bitter sensitive participants were less neophobic and preferred bitter vegetables
2

The complexity of neophobia in a generalist foraging corvid : the common magpie (Pica pica)

Vernelli, Toni January 2013 (has links)
It is often suggested that species differences in neophobia are related to differences in feeding or habitat specialisation. Generalist species, which have more to gain from exploring novel resources, tend to be less neophobic than specialists. However, some successful generalists including ravens, brown rats and coyotes also demonstrate high levels of neophobia. I explored this paradox using common magpies, a widespread generalist opportunist that displays behaviour indicative of high neophobia. Using a combination of field and short-term captive studies, I investigated whether novelty reactions were a fixed trait or varied according to object features and context as well as for different categories of novelty (i.e. objects, food, location). I found that novelty reactions in magpies were not influenced by object features such as colour, shape or size but varied greatly depending on environmental context and novelty category. Birds did not show avoidance of novel objects presented in novel environments but were extremely wary of similar novel objects presented in familiar environments, suggesting that violation of expectations may be more important than absolute novelty. Magpies could overcome the neophobia through repeated exploration of the objects over longer periods of time, but it affected their foraging behaviour. To avoid interactions with novel objects, wild-living magpies successfully employed an innovative technique that involves observing and pilfering from caching squirrels. Less aversion was shown towards novel food than to novel objects, while familiar objects and food encountered in novel locations were generally accepted. In total, this thesis suggests that neophobia is a complex and dynamic phenomenon in generalist foragers which may set protective limitations on the level of exploration. It can be overcome through learning and the development of alternative behavioural tactics such as kleptoparasitism.
3

The behavioural response of mice to predator odours

Blixt, Torbjörn January 2012 (has links)
The ability to detect and react to a predator odour is crucial for prey species. In the present study 10 mice (Mus musculus) were used to test the behavioural response of mice towards two predator odours (3-methyl-1-butanethiol and 3-mercapto-3-methyl-butan-1-ol) and one fruity odour (n-pentyl acetate). All three odours were tested against a near odourless blank stimulus (diethyl phthalate). The animals were individually placed in a test chamber of two equally sized compartments divided by a vertical Plexiglas wall with a semicircular opening. Their proximity to the odours, placed beneath the floor in petri dishes in each compartment, was measured continuously with stop watches. The mice spent less time in proximity to 3-methyl-1-butanethiol and n-pentyl acetate compared to diethyl phthalate (P<0,05). The mice did not prefer any specific compartment in the test with 3-mercapto-3-methyl-butan-1-ol compared to diethyl phthalate (P>0,05). The avoidance of 3-methyl-1-butanethiol and n-pentyl acetate can be explained either by neophobia, or in the case of 3-methyl-1-butanethiol that it contains sulphur. The lack of behavioural response towards 3-mercapto-3-methyl-butan-1-ol may be due to its loss of intensity over time. From this study it is not certain if mice have an innate fear of predator odours.
4

Examining the Predictors of Technical and Consumer Innovation in Black-Capped Chickadees (Poecile atricapillus)

Prasher, Sanjay 19 November 2018 (has links)
Behavioural innovation, the use of new behaviours or modification of existing ones in novel contexts, has been suggested to aid animals in meeting the demands of new or changing environments. Many researchers have studied intra-specific variation in the propensity for technical innovation (i.e. use of new or modified motor actions) using problem-solving tasks, but have found mixed results concerning the influence of individual and ecological variables. Relatively few researchers have investigated the predictors of consumer innovation (i.e. consumption of novel food). The aim of the work presented within this thesis is to ascertain which characteristics explain intra-specific variation in the propensity for technical and consumer innovation in black-capped chickadees. In chapter 2 I analyze dominance rank, exploratory tendency, and habitat urbanization as predictors of problem-solving performance and persistence. I found, for one of the tasks presented to the birds, that dominants outperform subordinates, particularly among rural individuals. This goes against predictions from the necessity drives innovation hypothesis, but may be explained by differences in experience, as adults were found to outperform juveniles in a follow-up analysis. There was also evidence for a positive relationship between exploratory tendency and lever-pulling performance. The lack of consistency in performance across tasks likely arose from differences in task characteristics. In chapter 3 I analyze the predictors of food neophobia and willingness to consume novel food using the same variables as before, as well as baseline levels of corticosterone. I found that birds responded differently to each novel food type and individuals became less neophobic and more willing to consume novel food items as the study progressed through autumn. Additionally, I found a negative relationship between baseline corticosterone levels and food neophobia, and a positive relationship between corticosterone levels and the propensity for consumer innovation. This finding is in line with the knowledge of higher baseline corticosterone driving foraging behaviour. Overall this work provides further insights into the characteristics that may drive innovation and allow animals to meet novel challenges or take advantage of novel opportunities in their environment.
5

Testování schopnosti "object permanence" u sýkor a vliv neofobie a individuálních exploračních strategií na úspěšnost sýkor v kognitivních úlohách / A test of "object permanence" in Paridae and effect of neophobia and individual explorative strategies on success in solving object permanence tasks

Marhounová, Lucie January 2015 (has links)
Object permanence (OP) is a cognitive ability that enables animals to mentally represent the existence of hidden objects even if they can not be perceived by senses. In humans, OP develops during six qualitative stages, in which the understanding of relationships between objects in space and time changes. Current research shows that primates, some carnivores and several species of birds also acquire various degrees of this ability depending on their social life and foraging strategies. Many studies of OP have focused on food-storing birds but yet only in the Corvidae family. Therefore we decided to test this ability in two species of the Paridae family, food-storing coal tit (Periparus ater, N=23) and non-storing great tit (Parus major, N=24) to find out which stage they can achieve and whether there is a difference between these species in relation to their caching ability. Our results suggest that food-storing coal tits search for completely hidden objects significantly better than great tits. Most of the great tits were not able to solve this task. However, the upper limit for both species is probably Stage 4 because coal tits probably solved OP tasks with more screens randomly or used alternative strategies rather than mental representation. Substantial interindividual variability in the...
6

Parental Perspective and Feeding Practices Effects on Food Neophobia in Elementary-Age School Children

Ayoughi, Farnoosh 01 October 2018 (has links)
The Food neophobia (FN) behaviors in children are developed during childhood and can be influenced by parental FN and feeding behaviors. The objective of this study was to evaluate the relationship between FN and fruit and vegetable neophobia (FVN) among parents, the parents-reports on child's behavior and child self-reports. The effect of parental feeding practices and demographic variables on children’s FN and FVN were evaluated. Sixty-eight parents paired with their elementary school children (aged 7-12 years) in San Luis Coastal Unified School District participated in this study. Results indicated that parents reported their children more neophobic than children self-reported neophobia; however, there was a significant association between parents-reported child FN and child self-reported FN (r=0.62, p<0.05). FVN behaviors were positively and consistently correlated with FN in both parents and children. Parents with the highest income levels used less restriction for weight and child control strategies to feed their children (p<0.05). More pressure to eat was applied significantly for younger children, which increased their levels of food and FVN as reported by parents.
7

Children's Acceptability of Vegetables: The Relationship Between Food Neophobia, Vegetable Neophobia, Picky Eating, Bitter Sensitivity, and Mouth Behavior

Egigian, Tara Lynn 01 August 2019 (has links) (PDF)
Although vegetables provide many beneficial nutrients and have been shown to help reduce the risk of dietary related chronic diseases, children in the United States are not meeting the national recommendations of vegetable servings. The overall goal of this research was to study the relationship between children’s vegetable acceptance and the following children’s characteristics: food neophobia (FN), vegetable neophobia (VN), picky eating (PE), 6-n-propylthiouracil (PROP) sensitivity, Mouth Behavior (MB). The specific objectives were to: (1) develop a novel method for evaluating children’s MB, (2) assess the FN, VN, PE, PROP sensitivity, and MB levels in children in San Luis Obispo County, (3) examine the relationship between FN, VN, PE, PROP sensitivity, and MB, (4) determine exposure and willingness to try familiar and unfamiliar vegetables of the two levels of each of the children’s characteristics, (5) to determine acceptability of familiar and unfamiliar vegetables of each level of each of the children’s characteristics, and (6) determine if the preference between two levels of each children’s characteristic differed. Children’s acceptability of familiar and unfamiliar vegetables was conducted with 43 child and parent pairs. Parents completed five questionnaires: demographics, the Child Food Neophobic Scale, the Fruit and Vegetable Neophobia Instrument (vegetable subscale), the Child-Feeding Questionnaire (pickiness subscale), and the JBMB® typing tool. Children participated in consumer acceptance testing of red carrots (stick, sliver, and puree) and broccoli (floret, sliver, and puree). Sensory attributes were measured using a 5-point facial hedonic scale. The children’s PROP sensitivity was determined by having the children place a control taste strip on their tongue for approximately ten seconds and report what they tasted. This procedure was repeated with a PROP taste strip. The children’s MB was determined through a guided discussion about their eating behaviors and food preferences with their parents. Of the children in the study, there were 46.51% FN, 32.56% PE, 34.8% PROP sensitive, 44.19% VN, 60.47% chewers, 27.91% crunchers, 6.98% smooshers, and 4.65% suckers. From likelihood ratio chi-square analysis, the following characteristics were related: FN and VN (p This study indicates there are possible trends between FN, PE, MB, and vegetable acceptance. Another trend that appeared was that the sensory attributes of the non-bitter, unfamiliar red carrots were often rated higher than the sensory attributes of the bitter, familiar broccoli. It may be possible to determine child’s MB through discussions with the child and their parent. In conclusion, knowledge of a children’s MB and understanding how their eating behaviors are associated with the acceptability of familiar and unfamiliar vegetables served in different product forms may be able to help increase children’s vegetable consumption.
8

Behavioural responses of mice to predator odour components

Sievert, Thorbjörn January 2015 (has links)
Having means to detect and avoid potential predators is a necessity for prey species. Most mammalian prey species are able to detect odours emitted by predators and to adapt their behaviour accordingly. These odour cues are therefore considered to act as semiochemicals. Predator odours consist of several dozen different odourants. In order to assess if single odourants elicit aversive behavioural reactions, predator-naïve CD-1 mice were presented with six odourants which are part of body-borne odours of different mammalian predator species. A two-compartment chamber was used in order to assess place-preference, motor activity and faecal excretions when the animals were simultaneously presented with a predator odourant and a blank control. Further trials were performed to assess whether the odourant concentrations had an influence on the behaviours. The only odourant that elicited a significant aversion was 3-methyl-1-butanethiol, a compound found in the anal gland secretion of skunks, when presented at a factor of 100 above the olfactory detection threshold of mice. Two other concentrations of 3-methyl-1-butanethiol did not elicit significant behavioural changes. Based on the present study, only one out of six selected predator odourants elicited a significant aversive response in CD-1 mice. This suggests that more than one odour component, or perhaps even the full mixture of odourants, may be necessary for CD-1 mice to respond to a predator odour with aversive behaviour.
9

Faktory ovlivňující variabilitu v reakcích sýkor (Paridae) vůči nové a aposematické kořisti. / Factors influencing variability i behaviour towards novel and aposematic prey in tits (Paridae)

Adamová, Dana January 2016 (has links)
Inter-specific and intra-specific variation in reactions towards novel and aposematic prey was found in several species of tits (Paridae). This Ph.D. thesis is focusing on various factors influencing reactions towards novel and aposematic prey in three European species of tits. We tested differences in exploration behaviour, neophobia, dietary conservatism, personality, age and experience as well as ability of avoidance learning and generalisation. We found no difference in exploration behaviour and in reaction towards novel prey in two different populations of great tits (Parus major). But the birds from the Finnish population were more neophobic than Czech birds, but they attacked aposematic firebug (Pyrrhocoris apterus) more often and faster than Czech birds. The difference can be explained by a different experience with local aposematic prey communities. Than we studied initial wariness in naive juveniles of great tits (P. major), coal tits (Periparus ater) and blue tits (Cyanistes caeruleus), and we tested how the initial wariness towards novel and aposematic prey can be deactivated by experience with palatable prey. Great tits and coal tits from experienced groups significantly decreased their neophobia towards both types of prey while blue tits did not change their strongly neophobic...
10

Neophobia and parental care in collared flycatchers (Ficedula albicollis)

Svedberg, Maja January 2023 (has links)
Parental care can be important especially in passerine birds and can depend on environment, food availability and behaviour. A behaviour that can affect the food supply for the offspring is neophobia, the fear of novel objects. The more fear the bird exhibits the less it visits the nest with food. In my study I aimed to examine neophobia and how it differed based on sex and if offspring number and weight influenced the behaviour. Video recordings of collared flycatchers nest boxes were used to see how the behaviour differed by placing a novel object on the nest box. The behaviours tested were duration of perching, hovering and visit including latency and frequency of visit. The results showed that there was a significant difference between the sexes in duration, latency, and frequency of visit but also duration of perching before and after placing a novel object on the nest box. In addition, my results showed that nestling weight significantly influenced frequency of visit and nestling number influenced duration of visit. The study shows that the collared flycatchers do express neophobia differently based on the sex and the nestling’s weight and number. Future studies could investigate if neophobia is a plastic behaviour and the effects of prolonged exposure to novel objects whichcould change the offspring’s survival chances or even the nestling’s behaviour.

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