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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.
451

Part I. - The Comparative Nutritive Value of Certain Locally Produced Poultry Rations, Part II. - Confinement Rearing

Hinds, H. B. 08 1900 (has links)
No description available.
452

Organohalogen contaminants in wildlife from the Yangtze River Delta : Development of methods and assessments of legacy and emerging persistent organic pollutants

Yin, Ge January 2016 (has links)
Rapid economic development has occurred during the past few decades in China with the Yangtze River Delta (YRD) area as one of the most progressive areas. The urbanization, industrialization, agricultural and aquaculture activities result in extensive production and application of chemicals. Organohalogen contaminants (OHCs) have been widely used as i.e. pesticides, flame retardants and plasticizers. They are persistent, bioaccumulative and pose a potential threat to ecosystem and human health. However, limited research has been conducted in the YRD with respect to chemicals environmental exposure. The main objective of this thesis is to investigate the contamination level, distribution pattern and sources of OHCs in the YRD. Wildlife from different habitats are used to indicate the environmental pollution situation, and evaluate selected matrices for use in long term biomonitoring to determine the environmental stress the contamination may cause. In addition, a method is developed for dicofol analysis. Moreover, a specific effort is made to introduce statistic power analysis to assist in optimal sampling design. The thesis results show extensive contamination of OHCs in wildlife in the YRD. The occurrences of high concentrations of chlorinated paraffins (CPs) are reported in wildlife, in particular in terrestrial species, (i.e. short-tailed mamushi snake and peregrine falcon). Impurities and byproducts of pentachlorophenol products, i.e. polychlorinated diphenyl ethers (PCDEs) and hydroxylated polychlorinated diphenyl ethers (OH-PCDEs) are identified and reported for the first time in eggs from black-crowned night heron and whiskered tern. High concentrations of octachlorodibenzo-p-dioxin (OCDD) are determined in these samples. The toxic equivalents (TEQs) of polychlorinated dibenzo-p-dioxin (PCDDs) and polychlorinated dibenzofurans (PCDFs) are at mean levels of 300 and 520 pg TEQ g-1lw (WHO2005 TEQ) in eggs from the two bird species, respectively. This is two orders of magnitude higher than European Union (EU) regulation limit in chicken eggs. Also, a novel pattern of polychlorinated biphenyls (PCBs) with octa- to decaCBs, contributing to as much as 20% of total PCBs therein, are reported in birds. The legacy POPs shows a common characteristic with relatively high level of organochlorine pesticides (i.e. DDT, hexacyclohexanes (HCHs) and Mirex), indicating historic applications. In contrast, rather low concentrations are shown of industrial chemicals such as PCBs and polybrominated diphenyl ethers (PBDEs). A refined and improved analytical method is developed to separate dicofol from its major decomposition compound, 4,4’-dichlorobenzophenone. Hence dicofol is possible to assess as such. Statistic power analysis demonstrates that sampling of sedentary species should be consistently spread over a larger area to monitor temporal trends of contaminants in a robust manner. The results presented in this thesis show high CPs and OCDD concentrations in wildlife. The levels and patterns of OHCs in YRD differ from other well studied areas of the world. This is likely due to the extensive production and use of chemicals in the YRD. The results strongly signal the need of research biomonitoring programs that meet the current situation of the YRD. Such programs will contribute to the management of chemicals and environment in YRD, with the potential to grow into the human health sector, and to expand to China as a whole. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 5: Submitted. Paper 6: Manuscript.</p><p> </p>
453

Enriquecimento do ovo: utilização de óleos de peixes e alga marinha como fontes de ácidos graxos poliinsaturados ômega-3 em rações de galinhas / Egg\'s enrichment: utilization of fish oils and marine algae as sources of omega-3 polyunsaturated fatty acids in hens\' diet.

Piber Neto, Eduardo 24 February 2006 (has links)
Foram utilizadas 168 galinhas poedeiras Hisex White em delineamento experimental inteiramente casualizado, com duração de cinco semanas. As aves foram distribuídas em sete tratamentos com três repetições cada, com o objetivo de verificar a influência da suplementação de três fontes marinhas de PUFAs n-3 - óleos de salmão (SA) e de atum e sardinha (A/S) e mistura de algas marinhas (AL), bem como sua combinações (SA+A/S, AL+SA, AL+A/S) - em relação ao grupo controle alimentado com ração basal de milho e soja (CON), sobre a qualidade do ovo e a composição lipídica da gema. A qualidade externa e interna do ovo não foi alterada significativamente pela adição de fontes de PUFAs n-3 na dieta das aves. A relação entre os lípides saturados : monoinsturados : poliinsaturados da gema (3,5 : 4,5 : 2,0) manteve-se constante com a adição dos suplementos de PUFAs n-3 na ração. Os óleos de salmão (SA) e de atum e sardinha (A/S) revelaram-se mais efetivos no enriquecimento da gema do ovo em PUFAs n-3, em especial o DHA. A relação PUFAs n-6/ PUFAs n-3 sofreu redução significativa com a adição das fontes marinhas de ômega-3 à dieta das galinhas. O EPA, embora em teores mais baixos que o DHA na gema do ovo, apresentou incremento significativo com o uso dos óleos de peixes (SA e A/S) adicionado à dieta em relação ao CON. O consumo de dois ovos enriquecidos com DHA do presente estudo, por dia, provavelmente atenderia os requerimentos diários deste PUFA n-3 para o ser humano / To investigate the influence of three PUFAs n-3 marine sources - salmon oil (SA), tuna and sardine oil (A/S), marine algae (AL) and combinations (SA+A/S, AL+SA, AL+A/S) - on egg quality and egg lipid composition, compared to a corn/soy control group (CON), 168 Hisex White laying hens were assigned into seven treatments with three repetitions in a randomized design during a experimental period of five weeks. The external and internal egg quality were not significantly affected by the addition of PUFAs n-3 marine sources into the hen diets. The saturated : monounsaturated : polyunsaturated ratio (3.5:4.5:2.0) remained constant by the supplementation of the marine sources into the diets. The salmon oil and the tuna and sardine oil showed the best results of PUFAs n-3 egg yolk enrichment, mainly the DHA. The PUFAs n-6/PUFAs n-3 ratio was significantly reduced by the inclusion of PUFAs n-3 sources into the hen diets. The EPA, although with lower levels than DHA into the egg yolk, showed a significant increase by the use of salmon oil and tuna and sardine oil added to the diet as compared to the control group (CON). The consumption of two DHA enriched eggs from this study per day probably would reach the daily requirements of this PUFA n-3 for the human been
454

Biologia reprodutiva de Ardeidae em três ninhais do Rio Grande do Sul, Brasil

Scherer, Janete de Fátima Martins 25 February 2010 (has links)
Made available in DSpace on 2015-03-05T16:20:41Z (GMT). No. of bitstreams: 0 Previous issue date: 25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Para o Rio Grande do Sul são registradas 624 espécies de aves, sendo que 123 espécies são descritas de hábitos aquáticos. Destas, destaca-se a família Ardeidae, pertencente à Ordem Ciconiiformes, a qual inclui os socós, as garças, os savacus que nidificam freqüentemente em bandos mistos, formando densos ninhais. Estes ninhais geralmente são construídos em arbustos de banhados, manguezais e ilhas. As espécies que geralmente nidificam no mesmo ninhal são Egretta thula, Nycticorax nycticorax, Ardea alba, espécies nativas, e Bubulcus ibis, espécie colonizadora oportunista e que possui fácil adaptação nos locais onde habita. O presente estudo intitulado como “Biologia reprodutiva de Ardeidae em três ninhais do Rio Grande do Sul, Brasil” foi realizado durante o período reprodutivo de Egretta thula, Bubulcus ibis, Nycticorax nycticorax e Ardea alba durante os anos de 2004 a 2006 e 2008 em três ninhais localizados nos municípios de Porto Alegre, Lindolfo Collor e Triunfo. O objetivo desta pesquisa foi avaliar a biol / The family Ardeidae frequently breeds in mixed colonies forming dense heronries. The present study aimed at verifying the breeding biology of four species in this family in three heronries of Rio Grande do Sul states during the years 2004 to 2009 through diary spot observations. Altogether, were registered 1403 nests and 4009 eggs distributed among species Nycticorax nycticorax, Bubulcus ibis, Ardea alba and Egretta thula. The species with the largest number of nests and eggs in all heronries was Bubulcus ibis, considering that in Triunfo it differed in number of nestlings along the years (P = 0.001). As for the heronry of Porto Alegre, A. alba differed significantly between the number of eggs (P = 0.02) and nestlings (P = 0.006) during the years. In Lindolfo Collor, the analysis of variance showed that there was no significant difference in the number of eggs and nestlings along the years (P > 0.05). Also, there wasn´t any significant difference in the number of eggs and nestlings for any species (P > 0.0
455

Effects of cool temperature on egg incubation, thermoregulation and physiological performance of tuatara (Sphenodon punctatus) : implications for conservation programmes

Besson, Anne Amelie, n/a January 2009 (has links)
Tuatara (Sphenodon spp.) were once widespread over both the North and the South Islands of New Zealand approximately 1000 years ago but are now restricted to offshore islands due to introduced predators and habitat destruction. The survival of tuatara is now threatened by climate change because of isolation on islands that prevent them from migrating to cooler regions, and by their limited capacity to adapt due to their long life span and low genetic diversity. The thermal suitability of cooler regions for future translocations could be the key for tuatara conservation. The overall aim of the study was to determine the effect of cool temperature on the physiology, behaviour and egg incubation of Cook Strait tuatara (Sphenodon punctatus). As well answering specific questions about tuatara and their adaptation to cool temperature this study aimed at answering general questions about the behavioural and evolutionary ecology of reptiles. I first compared the preferred body temperature, feeding responses and tolerance to cold temperature of tuatara (Sphenodon punctatus) with three lizard species that inhabit the Otago region of southern New Zealand: Hoplodactylus maculatus, Naultinus gemmeus and Oligosoma maccanni. As well as testing the co-adaptation hypothesis between preferred body temperature and physiological performance of reptiles, I wanted to determine whether tuatara (which are planned to be reintroduced from a warmer site to the Otago region) have similar responses to cool temperature as do Otago lizard species. I found that tuatara show responses to cold temperatures similar to those of lizards from southern New Zealand, suggesting that if tuatara are translocated outside of their geographical range, they are likely to survive. I then tested if tuatara were capable of modifying their thermoregulatory behaviour if translocated to a cooler region. To do so, I conducted a laboratory experiment in which tuatara were provided with three thermal treatments corresponding to the thermal environments they would experience in their current habitat and the proposed reintroduction site. Contrary to the prediction of the cost-benefit model of thermoregulation, tuatara became active thermoregulators when the thermal quality of the habitat decreased. The results suggest that the model is less applicable to cold-adapted species and that if translocated to cooler regions, tuatara will be able to adjust their thermoregulatory behaviour to their thermal environment. Tuatara are temperature-dependent sex determination (TSD) reptiles and their translocation to cooler regions could have an dramatic impact on the sex ratio of new populations. To determine if potentially lower incubation temperature would be a limiting factor for the reintroduction of tuatara, I translocated eggs to the proposed reintroduction site. Some tuatara embryos developed at the site (and later hatched in the laboratory), but incubation lasted longer than in natural nests and all hatchlings were female. This trend observed in biased sex ratio might change in the context of climate change as an increase of soil temperature by 3�C would allow the production of males at the proposed site. The present study demonstrates that the translocation of tuatara further south, outside of their current geographical range, is possible and recommended. Tuatara show similar responses to cool temperatures compared with lizards that live in southern New Zealand, they can also adjust their thermoregulatory behaviour if translocated to cooler habitats, and tuatara embryos could potentially develop successfully in cooler regions. The greatest chance for the future survival of tuatara and TSD species in general, lies in translocation to other locations that are thermally suitable.
456

The effects of dietary lysine, crude protein, energy and feed allocation on broiler breeder hen performance.

Patel, Jamila. 20 October 2014 (has links)
This study was conducted to investigate the effects of varying levels of dietary lysine and feed allocation, on the performance of female broiler breeders. In trial 1, 900 Cobb breeders from 26 to 45 weeks of age were used. The first four treatments had a fixed level of lysine throughout the experimental period, with 1200, 1070, 930 and 800 mg Lysine/bird/day and the last two treatments had their levels of lysine changed every two weeks, with treatment five started off with 1200 mg lysine/bird/day followed by a gradual decrease up to 975 mg lysine/bird/day at 45 week old, while treatment six started with the lowest level of lysine, 800 mg/bird/day and at 45 week old the intake was 1025 mg/bird/day. The rations provided 1900KJ ME/ day, the birds received 160 g of feed/day. Dietary lysine did not affect body weight, egg production, or egg composition. There were no significant differences in age at 50%, or peak production. Birds receiving 1070 and 1025 mg lysine/bird.day had a slightly, but not significantly, higher production in the current study. Birds receiving 1200 mg lysine/bird.day had the highest body weight and the lowest egg production. In trial 2, 900 broiler breeder hens were used. Protein intake and feed allocation were changed for each treatment at 26, 38 and 50 weeks and ending at 60 weeks. Birds on T1 were fed a constant CP content (145 g protein/kg) but a decreasing feed allocation (175 to 145 g/d). Those on T2 had a constant feed allocation (160 g/d) and a decreasing CP (166 to 124 g/kg) while those on T3 had varying levels of protein (166, 124 and 166 g/kg) and feed allocation (160, 160, 145 g/d). Mean cumulative protein intakes were 5.2, 5.3 and 4.8 kg/bird and mean energy intakes were 417, 412 and 402 MJ/bird for T1, T2 and T3 respectively. Body weights differed significantly at the end of the trial (P<0.05) with T2 showing the highest weight gain. However, egg production, egg weight and egg output were not affected by treatment. These breeders did not benefit from the additional protein and energy provided in the first and second periods by T1 and T2 (vs. T3), nor did they benefit from the additional energy provided in the final ten weeks of production by T2. / M.Sc.Agric. University of KwaZulu-Natal, Pietermaritzburg 2013.
457

Turtle nest sensory perception by raccoon (Procyon lotor) and striped skunk (Mephitis mephitis) : an approach through discrimination learning of potential nest cues

Galois, Patrick. January 1996 (has links)
Egg predation may be the most important mortality factor for North American turtles. This predation can destroy 50-90% of nests in an area. The major predators are striped skunks (Mephitis mephitis) and raccoons (Procyon lotor). Despite differences in their habits and diet, these species appear equally efficient in turtle egg predation, even though these eggs represent a very small portion of their annual food intake. Sight, olfaction, touch and hearing could be used by these predators to find the nests. The aim of this study was to document intra and inter-specific differences in the perception of possible nest-cues used by raccoon and striped skunk. Choice-tests based on food-conditioning were carried out with two visual cues (dark and smooth surface), one olfactory cue (turtle urine) and one tactile cue (soil compaction). Subject performances (number of trials to obtain 80% success rate in the different tests) were compared to assess intra and inter-species, and skunk inter-age differences in sensory perception and learning abilities. As expected raccoons learned the tactile cue discrimination faster than the visual cue discriminations. The tactile cue discrimination was learned as fast as the olfactory cue. As expected skunks learned the olfactory cue discrimination faster than other cue discriminations. When compared, the olfactory cue appeared to be as important for both species even though raccoons had faster learning rates than skunks in all the tests except for one visual test. Juvenile skunks learned faster than adult skunks with four out of six juveniles performing better in the olfactory test. Olfaction may play an important role in nest localization by raccoons and skunks, and sight may also play a role for raccoons. Learning turtle nest cues while with their mother could facilitate their future ability in locating turtle nests.
458

Factors affecting reproductive performance of the prawn, Penaeus monodon

Marsden, Gay Elizabeth January 2008 (has links)
The growth of the Penaeus monodon prawn aquaculture industry in Australia is hampered by a reliance on wild-caught broodstock. This species has proven difficult to breed from if broodstock are reared in captivity. Studies were therefore carried out to investigate factors controlling reproduction and influencing egg quality. Results of the studies revealed that patterns of nutrient accumulation during early ovary development are altered by captive conditions, possibly contributing to reduce larval quality. The sinus gland hormones were shown, together with the environment, to regulate two stages of ovary development. In a separate study it was further revealed that the hormone methyl farnesoate (MF) could negatively regulate the final stages of ovary development. Lastly it was shown that broodstock reared in captivity are less likely to mate and that this is due to inherent problems in both the male and the female prawns.
459

Effects of cool temperature on egg incubation, thermoregulation and physiological performance of tuatara (Sphenodon punctatus) : implications for conservation programmes

Besson, Anne Amelie, n/a January 2009 (has links)
Tuatara (Sphenodon spp.) were once widespread over both the North and the South Islands of New Zealand approximately 1000 years ago but are now restricted to offshore islands due to introduced predators and habitat destruction. The survival of tuatara is now threatened by climate change because of isolation on islands that prevent them from migrating to cooler regions, and by their limited capacity to adapt due to their long life span and low genetic diversity. The thermal suitability of cooler regions for future translocations could be the key for tuatara conservation. The overall aim of the study was to determine the effect of cool temperature on the physiology, behaviour and egg incubation of Cook Strait tuatara (Sphenodon punctatus). As well answering specific questions about tuatara and their adaptation to cool temperature this study aimed at answering general questions about the behavioural and evolutionary ecology of reptiles. I first compared the preferred body temperature, feeding responses and tolerance to cold temperature of tuatara (Sphenodon punctatus) with three lizard species that inhabit the Otago region of southern New Zealand: Hoplodactylus maculatus, Naultinus gemmeus and Oligosoma maccanni. As well as testing the co-adaptation hypothesis between preferred body temperature and physiological performance of reptiles, I wanted to determine whether tuatara (which are planned to be reintroduced from a warmer site to the Otago region) have similar responses to cool temperature as do Otago lizard species. I found that tuatara show responses to cold temperatures similar to those of lizards from southern New Zealand, suggesting that if tuatara are translocated outside of their geographical range, they are likely to survive. I then tested if tuatara were capable of modifying their thermoregulatory behaviour if translocated to a cooler region. To do so, I conducted a laboratory experiment in which tuatara were provided with three thermal treatments corresponding to the thermal environments they would experience in their current habitat and the proposed reintroduction site. Contrary to the prediction of the cost-benefit model of thermoregulation, tuatara became active thermoregulators when the thermal quality of the habitat decreased. The results suggest that the model is less applicable to cold-adapted species and that if translocated to cooler regions, tuatara will be able to adjust their thermoregulatory behaviour to their thermal environment. Tuatara are temperature-dependent sex determination (TSD) reptiles and their translocation to cooler regions could have an dramatic impact on the sex ratio of new populations. To determine if potentially lower incubation temperature would be a limiting factor for the reintroduction of tuatara, I translocated eggs to the proposed reintroduction site. Some tuatara embryos developed at the site (and later hatched in the laboratory), but incubation lasted longer than in natural nests and all hatchlings were female. This trend observed in biased sex ratio might change in the context of climate change as an increase of soil temperature by 3�C would allow the production of males at the proposed site. The present study demonstrates that the translocation of tuatara further south, outside of their current geographical range, is possible and recommended. Tuatara show similar responses to cool temperatures compared with lizards that live in southern New Zealand, they can also adjust their thermoregulatory behaviour if translocated to cooler habitats, and tuatara embryos could potentially develop successfully in cooler regions. The greatest chance for the future survival of tuatara and TSD species in general, lies in translocation to other locations that are thermally suitable.
460

Qualidade interna e externa de ovos de codornas japonesas armazenados em diferentes temperaturas e períodos de estocagem / Internal e external quality eggs Japanese quail eggs stored in different temperatures and periods of storage

Marinho, Andreza Lourenço 21 February 2012 (has links)
With the aim of evaluating the internal and external of eggs of quality quail stored under refrigeration and at room temperature, we used 440 eggs Japanese quail collected after laying. The eggs were distributed in a completely randomized design in factorial 2x11 (2 storage temperature x 11 storage periods) with 20 repetitions. Analyses were performed on eggs at 0, 3, 6, 9, 12, 15, 18, 21, 24, 27 and 30 days of storage. The variables analyzed were weight loss (%), specific gravity (g / ml), yolk index and albumen percentages (%) of yolk, albumen and shell, shell thickness (mm), yolk color, pH albumen and yolk and Haugh Unit. Statistical analysis was performed using the System Analysis Statistical and Genetic (SAEG) and means compared by Newman Keuls test at 5% probability. Observed effect was (P<0,05) linear weight loss of eggs (%), specific gravity (g / ml), yolk index, albumen index, albumen percentage, yolk percentage, pH and yolk Haugh unit, in both storage temperatures. However, the pH of the albumen had an effect (P<0,05) quadratic for eggs stored at both storage temperatures. To eggshell percentage, shell thickness and yolk color not found a significant effect (P>0,05) among treatments. We conclude that Japanese quail eggs can be stored for up to 18 days at room temperature and 30 days under refrigeration. / Fundação de Amparo a Pesquisa do Estado de Alagoas / Com o objetivo de avaliar a qualidade interna e externa de ovos de codornas armazenados sob refrigeração e à temperatura ambiente, utilizou-se 440 ovos de codornas japonesas coletados após a postura. Os ovos foram distribuídos em um delineamento inteiramente casualizado em esquema fatorial 2x11 (2 temperaturas de armazenamento x 11 períodos de armazenamento) com 20 repetições. As análises foram efetuadas nos ovos com 0, 3, 6, 9, 12, 15, 18, 21, 24, 27 e 30 dias de armazenamento. As variáveis analisadas foram: perda de peso (%), gravidade específica (g/ml), índice de gema e de albúmen, porcentagens (%) de gema, albúmen e casca, espessura de casca (mm), coloração da gema, pH do albúmen e da gema e a Unidade Haugh. As análises estatísticas foram realizadas, utilizando o Sistema para Análises Estatísticas e Genética (SAEG) e as médias comparadas pelo teste Newman Keuls a 5% de probabilidade. Observou-se efeito (P<0,05) linear para perda de peso dos ovos (%), gravidade especifica (g/ml), índice de gema, índice de albúmen, porcentagem de albúmen, pH da gema e unidade Haugh, em ambas as temperaturas de estocagem e porcentagem de gema para os ovos armazenados sob refrigeração. Contudo, o pH do albúmen apresentou efeito (P<0,05) quadrático para os ovos armazenados em ambas as temperaturas de estocagem e a porcentagem de gema para os ovos armazenados em temperatura ambiente. Para porcentagem de casca, espessura da casca e coloração da gema não se constatou efeito significativo (P>0,05) entre os tratamentos. Concluiu-se que ovos de codornas japonesas podem ser armazenados por até 18 dias em temperatura ambiente e 30 dias sob refrigeração.

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