Made available in DSpace on 2015-03-26T13:23:49Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1159386 bytes, checksum: b9aecb4a88db18841859a199194fc057 (MD5) Previous issue date: 2012-07-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Despite the meat quails are already in the Brazilian market for 16 years, there is little information in the areas of management, nutrition and environment as a whole, this fact often difficult to create and contribute to the increased cost of production of European species under the climate conditions of Brazil. It is considered that the creating quails cutting has great growth potential, thus making it of paramount importance studies related to the creation of this animal, both in terms of ambience associated with animal production, such as environmental aspects related to the characterization of waste produced, under different thermal conditions of creation. Based on the above, we aimed at, this work was to characterize and analyze the variation of components of the excreta of meat quails Coturnix coturnix coturnix strain, grown in growth chambers under different conditions of thermal environment. He had as specific objectives to evaluate the possible relationship between components and excreta moisture of the thermal environment for the creation of quails, and the relationship between components and characteristics of excreta with the thermal comfort ideal for quail, each week of the same. We will also evaluate the potential of ammonia emission from excreta in different micro-environmental conditions and determine the ratio carbon / nitrogen excreta so that we can calculate the optimal amount of specific sources of carbon to be added to the manure, composting for later efficient substrate generated. The study was conducted in AMBIAGRO-DEA/UFV, and conducted in two stages: the first stage 900 birds were used 1-21 days of age and second stage 300 birds were used 22-35 days of age. The first phase consisted of the following treatments: thermal comfort recommended in the literature for the three first weeks of life of the birds (36, 33, 30 ° C, respectively), two levels of heat stress (39, 36, 30 ° C and 42, 39, 36 ° C respectively), two levels of stress for cooling (33, 30, 27 and 30 ° C, 27, 24 ° C). In the second phase trial was a redistribution of the birds so that the quail each of the five treatments were initially subjected to a thermal comfort recommended position (26 ° C) and two levels of heat stress (30 ° C and 33 ° C) thus, new treatments 15. We analyzed the moisture content, pH, organic carbon, total nitrogen, total phosphorus, total sodium and total potassium in the excreta of the birds during the two phases. The variations of nitrogen and potassium found in the excreta of birds submitted to different thermal environments was not enough to ensure that these parameters serve as indicators of thermal stress of quails. Since the moisture content of the excreta of birds subjected to severe heat in the second phase of the experiment are higher than the value found in the excreta of birds subjected to thermal comfort, describing this factor as an indication that the birds are not in thermal comfort . The carbon / nitrogen ratio obtained in the excreta of quails, regardless of age and are subjected to the thermal environment, is less than ideal for composting, requiring addition of carbon material supplier. Very cold environments in early life or very hot in the growth phase and final meat quails, leading to more liquid feces and the consequent increased potential for ammonia emissions. / Apesar das codornas de corte já estarem no mercado brasileiro há 16 anos, ainda são escassas as informações nas áreas de manejo, nutrição e ambiência como um todo, este fato muitas vezes dificulta a criação e contribui para o aumento no custo de produção da espécie europeia sob as condições do clima do Brasil. Considera-se que a coturnicultura de corte possui grande potencial de crescimento, tornando-se assim, de suma importância estudos relacionados à criação desse animal, tanto em termos de ambiência associada à produtividade animal, como em aspectos ambientais relacionados à caracterização dos dejetos produzidos, sob diferentes condições térmicas de criação. Com base no exposto, objetivou-se, com este trabalho, caracterizar e analisar a variação de componentes das excretas de codornas de corte da linhagem Coturnix coturnix coturnix, criadas em câmaras climáticas, sob diferentes situações de ambiente térmico. Teve-se como objetivos específicos avaliar a possível relação entre componentes e umidade da excreta com o ambiente térmico de criação das codornas, e a relação entre componentes e características da excreta com o conforto térmico ideal para as codornas, a cada semana de vida das mesmas. Objetivou-se também avaliar o potencial de emissão de amônia das excretas em diferentes condições micro ambientais e determinar a relação Carbono/Nitrogênio das excretas com vistas ao calculo da quantidade ideal de fontes específicas de carbono a serem adicionadas aos dejetos, para uma posterior compostagem eficiente do substrato gerado. A pesquisa foi realizada no AMBIAGRO-DEA/UFV, e conduzida em duas fases: na primeira fase foram utilizadas 900 aves de 1 a 21 dias de idade e segunda fase foram utilizadas 300 aves de 22 a 35 dias de idade. A primeira fase foi constituída por cinco tratamentos: conforto térmico preconizado pela literatura para as três primeiras semanas de vida das aves, (36, 33, 30°C, respectivamente), dois níveis de estresse por calor, (39, 36, 30°C e 42, 39, 36 °C respectivamente), dois níveis de estresse por frio (33, 30, 27°C e 30, 27, 24°C). Na segunda fase experimental houve uma redistribuição das aves de forma que as codornas de cada um dos cinco tratamentos da primeira fase fossem submetidas a uma situação de conforto térmico preconizado (26°C) e a dois níveis de estresse por calor (30°C e 33°C) constituindo assim, 15 novos tratamentos. Foram analisados o teor de umidade, pH, carbono orgânico, nitrogênio total, fósforo total, sódio total e potássio total, nas excretas das aves durante as duas fases. As variações dos teores de nitrogênio e potássio encontrados nas excretas das aves submetidas a diferentes ambientes térmicos não foi suficiente para garantir que estes parâmetros sirvam como indicadores de estresse térmico de codornas. Já os teores de umidade das excretas das aves submetidas ao calor severo, na segunda fase do experimento, foram superiores ao valor encontrado nas excretas das aves submetidas ao conforto térmico, qualificando este fator como um indicativo de que as aves não se encontraram em conforto térmico. A relação carbono/nitrogênio obtida nas excretas de codornas, independente da idade e ambiente térmico a que estão submetidas, é inferior ao ideal para a compostagem, exigindo acréscimo de material fornecedor de carbono. Ambientes muito frios na fase inicial de vida ou muito quentes na fase de crescimento e final de codornas de corte, resultam em fezes mais liquidas e ao consequente maior potencial de emissão de amônia.

Made available in DSpace on 2015-03-26T13:54:55Z (GMT). No. of bitstreams: 1 texto completo.pdf: 209305 bytes, checksum: 0d6d8b132e97a2fe83f57d9f05c34f04 (MD5) Previous issue date: 2006-02-20 / Universidade Federal dos Vales do Jequitinhonha e Mucuri / An experiment was carried out in the Animal Science Department at the Universidade Federal de Viçosa. The objective was to determine the nutritional requirement of tryptophan for Japanese quail from 21 to 30 weeks of age. Four hundred Japanese quail, with initial weight of 158,49 grams and egg production average of 84,50%. The experimental design was completely randomized blocks, with eight blocks, in a factorial system of 5x3, with five levels of tryptophan and three experimental periods of 21 days each, all treatments were composed by eight repetitions of ten birds per repetition. The treatments consisted in five diets with 20% of crude protein, supplemented with five levels of L-tryptophan (0,000; 0,040; 0,080; 0,120 and 0,160%), providing a total of 0,120; 0,160; 0,200; 0,240 and 0,280% of digestible tryptophan, respectively. The birds were homogeneous according to the egg production rate and distributed in the cages, totally ten birds per cages. The studied variables were: feed intake (g/bird/day), tryptophan intake (mg/bird/day), egg production (%), production of marketable eggs (%/bird/day), egg medium weight (g), egg mass (kg/bird/day), feed conversion (kg intake feed per dozen eggs and kg eggs), weight of yolk (g), weight of albumen (g), weight of shell (g), percentage of yolk (%), percentage of albumen (%), percentage of shell (%), egg width (mm), egg length (mm), specific gravity (g/cm3) and units Haugh. Only the tryptophan intake, egg production rate, albumen weight, shell weight, percentage of shell, specific gravity and unit Haugh show significant effects (P<0,05) by tryptophan levels in the experimental diets. The performance of the quails in posture, respecting the statistical adjustment obtained through models of linear and quadratic regression and broken-line regression model, and the biological interpretation, allow us to conclude that to obtain the best productive performance, the quails diets should contain the level of 0,21% digestible tryptophan, what results in the daily intake of 45,0 mg per bird of tryptophan, corresponding to the relation of digestible tryptophan: digestible lysine ratio of 21%. / Desenvolveu-se um experimento, na seção de Avicultura do Departamento de Zootecnia, da Universidade Federal de Viçosa, com o objetivo de determinar a exigência nutricional de triptofano para codornas japonesas de 21 a 30 semanas de idade. Foram utilizadas 400 codornas, com peso inicial de 158,50 gramas e postura média de 84,50%. O delineamento experimental foi em blocos casualizados, contendo oito blocos, em esquema fatorial 5x3, sendo cinco tratamentos e três períodos experimentais de 21 dias, com oito repetições de dez aves/repetição. Os tratamentos consistiram de cinco dietas com 20% de proteína bruta, suplementada com cinco níveis de L-triptofano (0,000; 0,040; 0,080; 0,120 e 0,160%), fornecendo um total de 0,120; 0,160; 0,200; 0,240 e 0,280% de triptofano digestível, respectivamente. As aves foram homogenizadas segundo a taxa de produção de ovos e distribuídas nas gaiolas. As variáveis estudadas foram: consumo de ração (g/ave/dia), consumo de triptofano (mg/ave/dia), produção de ovos (%/ave/dia), produção ovos comercializáveis (%/ave/dia), peso médio dos ovos (g), massa de ovos (g/ave/dia), conversão alimentar (kg de ração/dúzia de ovos e por massa de ovos), peso de gema (g), peso de albúmen (g), peso de casca (g), porcentagem de gema (%), porcentagem de albúmen (%), porcentagem de casca (%), diâmetro do ovo (mm), altura do ovo (mm), gravidade específica (g/cm3) e unidade Haugh. As variáveis consumo de triptofano, produção de ovos, peso de albúmen, peso de casca, porcentagem de casca, altura do ovo, gravidade específica e unidade Haugh apresentaram efeitos significativos (P<0,05) dos níveis de triptofano nas dietas experimentais. As respostas de desempenho das codornas em postura, respeitando o ajuste estatístico obtido por meio de modelos de regressão linear e quadrática e do modelo descontínuo LRP, e a interpretação biológica, permitem concluir que para se obter o melhor desempenho produtivo, as dietas de codornas devem conter o nível de 0,21% de triptofano digestível, o que resulta no consumo diário de 45,0 mg/ave de triptofano, correspondendo à relação triptofano digestível: lisina digestível de 21%.

Made available in DSpace on 2015-03-26T13:55:16Z (GMT). No. of bitstreams: 1 texto completo.pdf: 663339 bytes, checksum: 0202276f09655d563ed0f8585c9cd278 (MD5) Previous issue date: 2013-03-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Two experiments were conducted aiming to establish the nutritional requirements of metabolizable energy (ME) for quails during 1-14 days of age, using 1,120 quails were distributed in a completely randomized design with seven treatments ( 2,600, 2,700, 2,800, 2,900, 3,000, 3,100 and 3,200 kcal / kg diet), eight replicates of 20 birds per experimental unit. Linearly decreased (P <0.01) in feed intake (FI), metabolizable energy (CEM), protein (CPB), lysine (CLIS) and feed conversion (FC) with increased levels of the dietary. The body weight (BW) and weight gain (WG) had a quadratic effect (P <0.03) the same observed for viability (VIAB) birds (P <0.01), estimating approximately 2,820 kcal / kg for both parameters. The content of dry matter (DM) and fat (EE) of the carcass increased linearly (P <0.01), while the moisture content decreased (A) (P <0.01) increased levels of energy diet. The protein content (CP) in the carcasses of birds was not influenced (P> 0.05) by EM. The requirement for quails 1-14 days of age, for better performance, higher viability of birds and proper carcass composition is 2820 kcal / kg diet, corresponding to a ratio of metabolizable energy: crude protein 108.6. In the second experiment, in order to determine the requirement for the period 15-35 days old, were used 560 quails were distributed in a completely randomized design, with five treatments (2.850, 2.950, 3.050, 3.150 and 3.250 kcal / kg diet), eight replicates with 14 birds per experimental unit. There was a linear decrease (P <0.01) in CR, CPB, CLIS and CA with increased levels of the dietary. CEM, PC, GP and VIAB were not affected (P> 0.05) by EM used. The levels of the diets did not affect (P> 0.05) on the DM, UM and protein content in PB quail carcasses. A quadratic effect (P <0.04) of levels of EE on the carcasses of birds. Thus the level of 2,850 kcal of ME / kg of feed, corresponding to a ratio of metabolizable emerged: crude protein 125.05, allows satisfactory performance of birds and carcass composition suitable. / Foram realizados dois experimentos objetivando-se de estabelecer as exigências nutricionais de energia metabolizável (EM) para codornas de corte no período de 1 a 14 dias de idade, utilizando-se 1.120 codornas de corte, distribuídas em delineamento inteiramente casualizado, com sete tratamentos (2.600; 2.700; 2.800; 2.900; 3.000; 3.100 e 3.200 kcal de EM/kg de ração), oito repetições com 20 aves por unidade experimental. Houve redução linear (P<0,01) no consumo de ração (CR), energia metabolizável (CEM), proteína (CPB), lisina (CLIS) e na conversão alimentar (CA) com o aumento dos níveis de EM da ração. O peso corporal (PC) e o ganho de peso (GP) apresentaram efeito quadrático (P<0,03) o mesmo observado em relação a viabilidade (VIAB) das aves (P<0,01), estimando-se aproximadamente 2.820 kcal de EM/kg para ambos os parâmetros. O teor de matéria seca (MS) e teor de gordura (EE) das carcaças aumentaram linearmente (P<0,01), enquanto o teor de umidade reduziu (UM) (P<0,01) com o aumento dos níveis energéticos da dieta. O teor de proteína (PB) nas carcaças das aves não foi influenciado (P>0,05) pelos níveis de EM. A exigência de EM para codornas de corte de 1 a 14 dias de idade, para melhor desempenho, maior viabilidade das aves e adequada composição de carcaça é de 2.820 kcal de EM/kg de ração, correspondendo a uma relação de energia metabolizável:proteína bruta de 108,6. No segundo experimento, com o objetivo de determinar a exigência de EM para o período de 15 a 35 dias de idade, foram utilizadas 560 codornas de corte, distribuídas em delineamento inteiramente casualizado, com cinco tratamentos (2.850; 2.950; 3.050; 3.150 e 3.250 kcal de EM/kg de ração), oito repetições com 14 aves por unidade experimental. Verificou-se redução linear (P<0,01) no CR, CPB, CLIS e CA com o aumento dos níveis de EM da ração. O CEM, PC, GP e VIAB não foram influenciados (P>0,05) pelos níveis de EM utilizados. Os níveis de EM das dietas não exerceram influência (P>0,05) sobre a MS, teor de UM e proteína PB nas carcaças das codornas. Foi observado efeito quadrático (P<0,04) dos níveis de EM sobre o EE nas carcaças das aves. Assim o nível de EM de 2.850 kcal de EM/kg de ração, correspondendo a uma relação de emergia metabolizável:proteína bruta de 125,05, possibilita desempenho satisfatório das aves e composição de carcaça adequada.

Made available in DSpace on 2014-07-29T15:07:46Z (GMT). No. of bitstreams: 1 Dissertacao Natali Gomes.pdf: 283005 bytes, checksum: 7137fd56067887481a4cc645f8148b81 (MD5) Previous issue date: 2008-03-28 / It was the objective of this study to evaluate the performance and reproductive parameters of different genetic groups of japanese quails between six and 26 weeks of age. There were used 384 japanese quails, assigned according to the experimental design (ramdomized blocks), considering the initial live weight of the birds as blocks in the beginning of the experiment. The treatments were three genetic groups with eight replicates, in a total of 48 experimental units with eight birds in each experimental unit (two males and six female). The birds were fed rations according to recommendations of NRC (1994), having soybean meal and ground corn as the main components. The variables of performance were studied every 14 days and three incubation trials were done with 15, 24 and 33 weeks of age. For the statistical analysis the proc GLM of SAS software was used and the means were compared by the t Student test. In each incubation study the completely ramdomized blocks experimental design was used, considering the incubating machines as blocks, with 70 replicates per treatment and one egg as the experimental unit. The parameters evaluated were the egg weight, hatchability, chick weight at hatching, weight loss and weight after six hours of fasting. The results were submitted to variance analysis and the means compared by the t Student test (5% of probability). The genetic groups presented differences among each other for the live body weight in the beginning of production, age at 50% of of productiontwere different to body weight at the beggining and age at 50% of production, where the commercial parent line obtained the best performance. The parameters peak persistence, eggs production, feed intake, viability and beak behavior did not present differences among the genetic groups. The live body weight influenced the egg weight. In the incubation trials the commercial parent line presented more weight of the incubating egg and more weight of the chicks at hatching. It was concluded in the present study that there are statistical differences on the performance and incubating parameters among genetic groups of japanese quails. / O objetivo deste estudo foi avaliar o desempenho e parâmetros reprodutivos de diferentes grupos genéticos de codornas japonesas entre seis e 26 semanas de idade. Foram utilizadas 384 codornas japonesas, distribuídas de acordo com delineamento experimental em blocos casualizados, considerando como blocos os pesos das aves no início do experimento. Os tratamentos estudados foram três grupos genéticos, com oito repetições, totalizando 48 parcelas com oito aves cada (dois machos e seis fêmeas). As aves receberam rações formuladas a partir de recomendações contidas no NRC (1994) tendo como base farelo de soja e milho moído. As variáveis de desempenho foram estudadas a cada período de 14 dias e foram realizados três ensaios de incubação, com 15, 24 e 33 semanas de idade. Para a análise estatística utilizou-se o procedimento GLM do programa SAS e as médias comparadas pelo teste t de Student. Em cada ensaio de incubação, foi adotado o delineamento experimental em blocos casualizados, sendo considerados blocos as incubadoras, com 70 repetições por tratamento, sendo considerado um ovo a parcela. As variáveis estudadas foram peso do ovo, eclodibilidade, peso ao nascer, perda de peso e peso no alojamento. Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste t de Student (5% de probabilidade). As linhagens apresentaram diferenças entre si para peso ao início de produção e idade aos 50% de produção, sendo que a linhagem comercial apresentou os melhores resultados. Para as variáveis persistência de pico, produção de ovos, consumo de ração, viabilidade e comportamento de bicagem não foram observadas diferenças entre as linhagens. O peso das aves influenciou o peso do ovo. Nos ensaios de incubação, a linhagem comercial apresentou maior peso de ovo incubável e maior peso ao nascer das codorninhas. Conclui-se no presente estudo que há diferenças significativas para desempenho e parâmetros de incubação entre as linhagens de codornas japonesas estudadas.

Neophobia, the fear of novelty, is a behavioral trait found across a number of animal species, including humans. Neophobic individuals perceive novel environments and stimuli to have aversive properties, and exhibit fearful behaviors when presented with non-familiar situations. The present study examined how early life exposure to aversive novel stimuli could reduce neophobia in bobwhite quail chicks. Experiment 1 exposed chicks to a novel auditory tone previously shown to be aversive to naïve chicks (Suarez, 2012) for 24 hours immediately after hatching, then subsequently tested them in the presence of the tone within a novel maze task. Postnatally exposed chicks demonstrated decreased fearfulness compared to naïve chicks, and behaved more similarly to chicks tested in the presence of a known attractive auditory stimulus (a bobwhite maternal assembly call vocalization). Experiment 2 exposed chicks to the novel auditory tone for 24 hours prenatally, then subsequently tested them within a novel maze task. Prenatally exposed chicks showed decreased fearfulness to a similar degree as those postnatally exposed, revealing that both prenatal and postnatal exposure methods are capable of decreasing fear of auditory stimuli. Experiment 3 exposed chicks to a novel visual stimulus for 24 hours postnatally, then subsequently tested them within a novel emergence box / T-maze apparatus. Chicks exposed to the visual stimulus showed decreased fearfulness compared to naïve chicks, thereby demonstrating the utility of this method across sense modalities. Experiment 4 assessed whether early postnatal exposure to one novel stimulus could generalize and serve to decrease fear of novelty when chicks were tested in the presence of markedly different stimuli. By combining the methods of Experiments 1 and 3, this experiment revealed that chicks exposed to one type of stimulus (auditory or visual) demonstrated decreased fear when subsequently tested in the presence of the opposite type of novel stimulus. These results suggest that experience with novel stimuli can moderate the extent to which neophobia will develop during early development.

<p>Humans have altered natural landscape since the agricultural revolution, but it has been most destructive since human globalization and rampant industrialization in the last two centuries. These activities deteriorate and fragments natural habitat of many wild species that creates small isolated populations that lose genetic diversity over time. Loss of genetic diversity reduces the adaptive capacity of a population to respond to future environmental change and increases their extinction risks. Implementing strategies for wildlife conservation is a challenge primarily because of our lack of understanding of the biology of many wild species, the risks they are currently facing, and their evolutionary histories. With the advent of genomic and computational techniques, it is now possible to address these concerns. In my research, I used genomics to study the evolutionary history of the Montezuma Quail (<i>Cyrtonyx montezumae</i>) and created monitoring tools that can be readily applied by wildlife managers for its conservation. Montezuma Quail is a small gamebird found mostly in Mexico with peripheral populations existing in Arizona, New Mexico, and Texas. Montezuma Quail are going through species wide decline in the United States and are listed as vulnerable in the state of Texas due to their small population sizes and geographic isolation from rest of the range. My results show that Texas quail are genetically distinct and significantly less diverse than Arizona quail. Analysis of whole genome sequences from multiple individuals show that due to small population sizes and isolation, Texas quail are significantly more inbred and genetic drift is the major contributor for loss of genetic diversity we see today. Inbreeding is negatively impacting Texas quail as they carry more deleterious alleles within their genome that reduce fitness of the individuals. Demographic models predict that both Arizona and Texas populations were formed via founding bottlenecks around 20,000 years ago. Texas populations have maintained small population sizes since its split from the ancestral populations and are less efficient in purging new deleterious mutations that arise post-bottleneck. The inferences from my research not only carries direct implications for Montezuma Quail conservationists, but also illustrate the power of evolutionary genomics in implementing targeted management strategies for any species that face existential threats in today’s waning world. </p>

Since their emergence in the early 1990s, neonicotinoid use has increased exponentially to make them the world's most prevalent insecticides. Although there is considerable research concerning the lethality of neonicotinoids, their sub-lethal and developmental effects are still being explored, especially with regards to non-mammalian species. The goal of this research was to investigate the effects of the neonicotinoid imidacloprid on the morphological and physiological development of northern bobwhite quail (Colinus virginianus). Bobwhite eggs (n = 650) were injected with imidacloprid concentrations of 0 (sham), 10, 50, 100 and 150 grams per kilogram of egg mass, which was administered at day 0 (pre-incubation), 3, 6, 9, or 12 of growth. Embryos were dissected on day 19 when they were weighed, staged, and examined for any overt structural deformities. Embryonic heart, liver, lungs and kidneys were also weighed and preserved for future use. Treated embryos exhibited increased frequency of severely deformed beaks and legs, as well as larger hearts and smaller lungs at the higher dosing concentrations. Some impacts are more pronounced in specific dosing periods, implying that there may be critical windows of development when embryos are highly susceptible to neonicotinoid exposure. This investigation suggests that imidacloprid could play a significant role in chick survival and declining quail populations in treated regions of the country.

No description available.

The global decline of pollinators, insects and animals that assist in pollination and fertilizing plants, poses a great risk to global food supply. This study investigates if people have preferences for a program to abate decline in a region along the East Coast of the United States. A survey is used to investigate these preferences and connections to the region to understand if individual connections can explain preferences. The majority of people were found to not have preferences to help increase pollinator abundance. Additionally, measures of connection to the region were found to be insignificant in explain individual preferences. / Master of Science

Submitted by Jordan (jordanbiblio@gmail.com) on 2017-03-02T15:47:42Z No. of bitstreams: 1 DISS_2015_Merik Rocha Silva.pdf: 906319 bytes, checksum: cdabe1d5bf2be64c1bdf695157237bfe (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-03-03T11:59:38Z (GMT) No. of bitstreams: 1 DISS_2015_Merik Rocha Silva.pdf: 906319 bytes, checksum: cdabe1d5bf2be64c1bdf695157237bfe (MD5) / Made available in DSpace on 2017-03-03T11:59:38Z (GMT). No. of bitstreams: 1 DISS_2015_Merik Rocha Silva.pdf: 906319 bytes, checksum: cdabe1d5bf2be64c1bdf695157237bfe (MD5) Previous issue date: 2015-03-20 / Objetivou-se avaliar modelos de regressão não linear utilizando as funções de Brody, Gompertz, Logístico, Morgan-Mercer-Flodin (MMF), Richards e von Bertalanffy na análise e interpretação da curva de crescimento de codornas de corte. Foram utilizados 30.410 registros de peso corporal, mensurados aos 1, 7, 14, 21, 28, 35 e 42 dias de idade de codornas de corte machos e fêmeas, participantes do Programa de Melhoramento Genético da Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Os modelos foram utilizados sob o enfoque de modelos fixos e também sob enfoque de modelos mistos. Dentre as funções utilizadas a de Brody não convergiu satisfatoriamente. Considerando modelos fixos e com base nos Critérios de Informação de Aikake (AIC) e Bayesiano (BIC) foi identificado o modelo de Gompertz como mais ajustado. Ao considerar o peso corporal assintótico, denominado parâmetro “A”; como aleatório, os modelos Gompertz, Logístico, MMF e von Bertalanffy apresentaram redução nas estimativas de desvio-padrão residual e melhores estimativas para AIC e BIC. Ao considerar o parâmetro “K” como aleatório, somente Richards apresentou convergência; e nenhum dos modelos apresentou convergência tendo A e K, simultaneamente como aleatórios. Entre os modelos mistos, Richards apresentou os menores valores de AIC e BIC, porém com problemas na matriz Hessiana, que resultou na estimação de parâmetros inutilizáveis, provavelmente devido a multicolinearidade entre parâmetros. Assim, o uso de modelos não-lineares mistos provocou redução do viés de predição com a redução do desvio-padrão residual, sendo o modelo MMF o mais apropriado para a descrição da curva de crescimento das codornas de corte. / Non-linear regression models were evaluated with Brody, Gompertz, Logistic, MorganMercer-Flodin (MMF), Richards and von Bertalanffy functions in the analysis and interpretation of the growth curve for broiler quails. Further, 30,410 body weight registers were used at 1, 7, 14, 21, 28, 35 and 42 days old of male and female quails for the Genetic Improvement Program of the Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Models comprised fixed and mixed modalities. Brody function failed to converge efficiently, whereas the Gompertz model proved to be the most adjusted when fixed models based on Aikake (AIC) and Bayesian (BIC) Information Criteria were taken into consideration. When the asymptotic body weight, called parameter A, is randomized, the Gompertz, Logístico, MMF and von Bertalanffy models had a decrease in residual standard deviation estimates and an increase for AIC and BIC. In the case of randomized parameter K, only Richards function converged, whilst no model converged with A and K simultaneously randomized. Richards had the lowest AIC and BIC rates among the mixed models, featuring problems in the Hessian matrix resulting in the estimation of unusable parameters, perhaps due to the multi-co-linearity among the parameters. Mixed non-linear models reduced prediction bias when the residual standard deviation was reduced. The MMF model fitted best to describe the growth curve of broiler quails.