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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.
141

Is sugar as sweet to the palate asseeds are appetizing to the belly? : Taste responsiveness to seven sweet-tastingsubstances in white-faced sakis (Pithecia pithecia)

Redin Hurtado, Mikel January 2023 (has links)
Differences in taste perception between species are thought to reflect evolutionaryadaptations to dietary specializations such as seed predation. By employing a two-bottlepreference test, the purpose of the current study was to evaluate the taste responsiveness forfive food-associated carbohydrates and two steviol glycosides in four adult white-faced sakis(Pithecia pithecia). The taste preference thresholds were found to be 10 mM for sucrose, 10-40 mM for fructose, 20-30 mM for glucose and maltose, and 30-40 mM for lactose. The sakisalso showed a clear preference for rebaudioside A and stevioside over tap water atconcentrations as low as 0.04 and 0.2-0.5 mM, respectively. When given the choice betweenall binary combinations of the five carbohydrates at equimolar concentrations of 100, 200,and 300 mM, respectively, the sakis displayed the following preference pattern: sucrose >fructose > glucose ≥ maltose = lactose. The obtained taste preference thresholds for foodassociated carbohydrates fall into the lower range of values among primates, suggesting acomparatively high sweet-taste sensitivity in the sakis. The pattern of relative preferenceswas consistent with that reported in most tested primates. Altogether, the responsivenesstowards the sweet-tasting substances obtained in this seed predator resembles the resultsobtained in primates which act as seed dispersers. However, these results might reflect anevolutionary adaptation of white-faced sakis to exploit resources containing low sugarconcentrations such as unripe fruits and seeds.
142

Long-term stress, behaviour, and the dog-owner relationship in rehomed dogs.

Löf, Jenny January 2022 (has links)
Humans and dogs have been living close for over 15,000 years, resulting in a unique relationship. The dog-owner relationship can affect stress, and could be affected by contact-seeking behaviour, personalities, and behavioural synchronization. Due to Covid-19, an increase in registered dogs could be observed. This could lead to more dogs being rehomed once the restrictions are eased and people go back to their workplaces, hence the importance of more knowledge concerning rehomed dogs and their behaviour, stress, and the relationship to its new owner. Thirty rehomed dogs (26 owners) and 31 control dogs (28 owners) participated. Dogs and their owners were tested in an unsolvable problem task to observe contact-seeking behaviour, and a behavioural synchronization test was conducted. Afterwards, dogs were equipped with activity collars to measure physical activity and dog-hair was collected to assess long-term stress. In addition, owners completed three questionnaires to assess the dog-owner relationship, and the personalities of the dogs and their owners. The results revealed no significant differences in behavioural synchronization, contact-seeking behaviour, stress, physical activity, or the dog-owner relationship between rehomed and control dogs. However, owners owning a rehomed dog potentially scored higher on the personality trait “agreeableness”, and rehomed dogs were potentially scored as more fearful of handling and less playful than control dogs. In conclusion, there is potentially a difference in personality traits in both dogs and owners between the groups, however, rehomed dogs are similar to control dogs in terms of behavioural synchronization, contact-seeking behaviour, long-term stress, and the dog-owner relationship.
143

Dominance relationships and Daily activity in the Spotted hyenas (Crocuta crocuta) at the Zoo of Borås

Stade, Isabelle January 2024 (has links)
The Spotted hyena (Crocuta crocuta) is a gregarious carnivore known for its strictly structured hierarchical rank relationships. At the zoo of Borås a clan, consisting out of two Spotted hyenas, are participating in an ex-situ program. In order to successfully enact conservational work, within zoos, sustainable management of zoo populations is of importance, and the behavioral aspect is vital in enabling welfare. In this study, I observed social interactions and activity in the Spotted hyenas at the zoo of Borås, for ten continuous days. The study aimed to investigate the dominance relationship and daily activity of the individuals. Furthermore, if this correlates with concentrations of testosterone. I performed two different observational studies, one focusing on social and agonistic behaviors, and the other on general behaviors. A third method, blood sampling, was intended to be performed but due to non-optimal conditions it was not executed. The results implied that the two individuals were highly nocturnal, with activity peaks to be observed during the first half of the night and at dawn. The individuals spent the majority of the time, 60.6%, resting which signifies that they are active during shorter periods. They were highly social with each other, but force measurements and aggressive displays did occur, mainly during the night. Sansa was the one taking initiative in conflicts, which suggests attempts in dominating Arya. Further, this indicates that the activity and dynamic of the individuals resembles that of a wild population, along with corresponding with previously performed studies and behavioral descriptions.
144

Stress and the Offspring : Adaptive Transgenerational Effects of Unpredictability on Behaviour and Gene Expression in Chickens (<em>Gallus gallus</em>)

Nätt, Daniel January 2008 (has links)
<p>Environmental stress has shown to affect both the exposed individuals and the development of their offspring. Generally, it is thought that the stressed organism responds to stress by trying to adapt to it. This thesis investigates possible evolutionary consequences of cross-generational transmissions of stress, where the parent has been stressed but the offspring has not. In two studies we have exposed chicken parents of different breeds to an unpredictable circadian light rhythm, to investigate the influence of genetic background on the transmission of behaviour and patterns of genome-wide gene expression across generations. In Paper I, we can show that the domesticated chicken, by means of epigenetic factors, transmit their behaviours as well as their gene expression profiles to their offspring to a higher extent than their wild ancestor, the red junglefowl. Furthermore, in Paper II, even though the offspring never experienced the stress or had any contact with their stressed parents, they seemed to have adapted to it, which suggests that the parents might have prepared (or pre-adapted) them for living in the unpredictable environment. Additionally, eggs of stressed hens showed increased levels of estradiol that might have affected gene expression of specific immune genes, which were up-regulated in the offspring of stressed parents. It is possible that the traditional distinction between stress responses and evolutionary adaptation may be reevaluated, since our results indicate that they could be parts of the same evolutionary event.</p>
145

Beteendesyndrom hos blankål (Anguilla anguilla): aktivitet och respons på främmande objekt i en artificiell miljö / Behavioural syndromes in silver eel (Anguilla anguilla): activity and response to novel objects in an artificial environment

Ingelman Åslund, Trollet January 2020 (has links)
Ökad kunskap om djurs beteendesyndrom kan möjliggöra förbättrade bevarandeåtgärder för hotade arter. I den här studien genomgick 108 blankålar (Anguilla anguilla) två beteendetester; “open-field test” och “novel-object test”. Ålars morfologi och val av föda, habitat och dygnsaktivitet har i tidigare studier visats hänga ihop. I den här studien undersökte jag om det fanns något samband mellan ålarnas morfologi, aktivitet samt respons på främmande föremål. De ålar som var mest aktiva under open-field-testet var också de ålar som visade störst intresse för det främmande föremålet i novel-object-testet. Det fanns dock inte något samband mellan morfologi och aktivitet eller mellan morfologi och respons på främmande föremål. Detta innebär att ett utforskande och djärvt beteendesyndrom har upptäckts hos vissa av ålarna, medan den bakomliggande faktorn fortsätter vara okänd. / Increased knowledge of behavioural syndromes may contribute to enhancing our conservation methods for endangered species. In this study, the behavior of 108 silver eels (Anguilla anguilla) was assessed in two assays: an open-field test and a novel-object test. Eel morphology and diel activity as well as diet and habitat use have previously been shown to correlate with each other. In this study, I investigated the potential relationship between the morphology, activity and response to a novel object. The most active eels during the open-field test were also the ones that expressed the most interest for the novel object. There was, however, no correlation between morphology and activity or morphology and response to the novel object. This means an exploring and bold behaviour syndrome was discovered amongst some of the eels, whilst the underlying cause remains unknown.
146

Positive welfare indicators of the domestic pig (Sus scrofa domesticus), a review : Which of the indicators are being used for the on-farm evaluation of pig’s positive welfare? / Positiva välfärdsindikatorer för den domesticerade grisen (Sus scrofa domesticus), en översyn : Vilka indikatorer används för att utvärdera grisens positiva välfärd på gårdsnivå?

Papageorgiou, Maria January 2022 (has links)
Since the 1960s the focus of animal welfare has been mainly on the negative aspects of welfare and on minimizing and alleviating these negatives. Lately, the focus has been not only on the negative features of welfare that should be kept above a minimum standard, but also on the positive ones that should be enforced. Positive welfare goes a step beyond the common welfare approach and focuses additionally on the positive aspects that animals should have in their lives. This review analyses the behavioral indicators that have been proposed as positive welfare indicators of the domestic pig and have been studied theoretically or experimentally. Various behavioral indicators have been proposed but play is the positive indicator that has been studied the most, followed by exploratory and social affiliative behaviors. Vocalizations and ear and tail postures have also been proposed as promising positive welfare indicators but more research is needed to clearly understand the expression of these behaviors and the affective states that they indicate. According to the literature results, the Welfare Quality protocol for pigs is the only protocol that evaluates the positive welfare of the pig on the farm level. Play, exploratory and social affiliative behaviors are being measured. In addition, positive emotions are being measured via Qualitative Behavioral Assessment (QBA). / Efter 1960-talet, fokuserar djurvälfärden huvudsakligen på de negativa aspekterna av välfärd och på att minimera och lindra de negativa aspekterna. Under de senaste åren, har fokus legat inte bara på att minimera de negativa aspekterna och hålla dem över en minimistandard utan också på att förstärka de positiva. Positiv välfärd går ett steg framåt i det gemensamma välfärdssynsättet och fokuserar dessutom på de positiva aspekterna som djur bör ha i sina liv. Denna översyn analyserar de positiva beteendeindikatorer på djurvälfärd, de som har föreslagits som positiva välfärdsindikatorer för den domesticerade grisen och har studerats teoretiskt eller experimentellt. Bland alla indikatorer har lekbeteende studerats mest, följt av undersökingsbeteende och sociala affiliativa beteenden. Vokalisationer och öron- och svansställningar har också föreslagits som lovande positiva välfärdsindikatorer men fler studier bör göras för att tydligt förstå uttrycket av dessa beteenden och grisens känslor som de indikerar. Enligt litteraturen, är Welfare Quality protokoll för grisar det enda protokollet som utvärderar grisens positiva välfärd på gårdsnivå. Lekbeteende, undersökningsbeteende och sociala affiliativa beteenden mäts. Dessutom, positiva känslor mäts via QBA.
147

Investigating fin whale (Balaenoptera physalus) sightings in Skjálfandi Bay, Iceland, and potential migratory movements through photo-identification

Lundström, Hanna January 2023 (has links)
In studies of migration and life-history of many large whales, photo-identification has proven a very powerful tool. Unfortunately, photo-identification is not as established and common when it comes to the second largest animal on earth, the fin whale (Balaenoptera physalus).Despite the massive size of the creatures many things remain unknown about them, such asmigration patterns, the geographical and temporal locations of wintering and individual seasonal range. This study aimed to investigate when fin whales normally visit Skjálfandi Bay, Iceland, and if they migrate between Skjálfandi Bay and Ireland, using photo-identification. The results showed somewhat that the fin whale visits in Skjálfandi Bay were most common in March and April which could be connected to arrival of schooling fish such as capelin (Mallotus villosus) early spring, and that visits have not changed noticeably over the years, suggesting that the fin whales will keep coming to Skjálfandi Bay. One possible fin whale match was found between Skjálfandi Bay and Ireland, suggesting but not confirming migration between the two locations. Further investigation is needed to understand fin whale migration patterns. Because of typical fin whale behavior, similar dorsal fins and unreliable weather, the photo-identification system was discussed, and improvements suggested. A more established photo-identification system could include fin whale photo-ID catalogues with pictures from dorsal view and from the left and right side. However, the photo-identification methods need further investigating to improve even more and to find the best possible way to identify and photograph fin whales. / Foto-identifiering har visat sig vara ett användbart verktyg för att studera migration men även livshistoria hos många stora valar. Tyvärr är fotoidentifiering inte lika etablerat och vanligt när det gäller det näst största djuret vår jord, sillvalen (Balaenoptera physalus). Trots valens massiva storlek finns det en stor kunskapsbrist kring dess migrationsmönster, de geografiska och tidsmässiga platserna för övervintring och individuellt säsongsutbrednings-område bland annat. Denna studie syftade till att undersöka när sillvalarna normalt kommer till Skjálfandi Bay, Island, och om de migrerar mellan Skjálfandi Bay och Irland, med hjälp av foto-identifiering. Resultaten visade delvis att sillvalarna oftast besöker Skjálfandi Bay i mars och april, vilket kan vara kopplat till att stimfiskar såsom lodda (Mallotus villosus) kommer dit tidig vår, och att besökssiffrorna inte har ändrats mycket över åren vilket tyder på att sillvalarna kommer fortsätta komma till Skjálfandi Bay. En möjlig matching hittades mellan en identifierad sillval i Skjálfandi Bay och en identifierad sillval i irländska vatten, vilket tyder på men inte bekräftar migration mellan de två platserna. På grund av det typiska sillvalbeteendet och derasliknande ryggfenor samt det opålitliga vädret som en faktor, diskuterades fotoidentifieringssystemet och förbättringar föreslogs. Ett mer etablerat fotoidentifieringssystem hade kunnat inkludera fotoidentifieringskataloger med bilder på sillvalar från ovan sida och från båda sidor. Däremot behöver fotoidentifieringsmetoderna vidare undersökning för ytterligare förbättringar och för att hitta det bästa sättet att identifiera och fotografera sillvalar.

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