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The Costa Rican coturniculture sector is yet in development. Production, economic or marketing aspects associated with the activity have not been previously documented in the existing literature. The objective of this study is to generate information about marketing and consumption patterns of quail eggs in Costa Rica. The investigation took place between January and December 2019 in the Greater Costa Rican Metropolitan Area. Survey was applied to 14 producers evaluating the commercial environment, while the consumption patterns of quail egg were evaluated in a sample of 300 people. Most of the producers (10) are dedicated to the exclusive production of eggs mostly in farms that do not exceed 200 birds (11), mainly housed in artisanal cages (10), where the use of production records has not been implemented (11). They essentially use poultry feed (13) without distinction of the productive stage of the bird (11), without reproductive management in six of the cases, or using consanguineous crosses (5). The egg is sold mainly in packages of 24 units ($2.42 each package) and canned 200 g ($2.5). In terms of purchase, most consumers expressed that they don´t purchase quail eggs (74%), with sporadic consumption even among those who do obtain it (51.4% once a month). When purchased, the preferred presentation the fresh packaged egg (46.8%) and is prepared mainly as hardboiled egg (66.2%). The production and consumption of quail eggs in Costa Rica is low-tech and low diversified, which is consistent with a profile of small producers and low consumption patterns., El sector coturnicultor costarricense está en proceso de desarrollo; aún no se han documentado en la literatura aspectos productivos, económicos, de mercado o comercialización asociados al mismo. El objetivo de este trabajo es generar información sobre la comercialización y el consumo del huevo de codorniz en Costa Rica. La investigación tuvo lugar entre enero y diciembre del 2019 en la Gran Área Metropolitana costarricense. Se realizaron consultas a 14 productores con respecto al entorno comercial, a la vez que se evaluaron las pautas de consumo de huevo de codorniz en una muestra de 300 personas. La mayoría de los productores (10) se dedican a la producción exclusiva de huevo en sistemas productivos que mayoritariamente no superan las 200 aves (11), principalmente alojadas en jaulas artesanales (10), y donde el uso de registros productivos no se ha implementado (11). Se emplea esencialmente alimento para gallinas de producción(13), sin distinción de la etapa productiva del ave (11), sin un manejo reproductivo en seis de los casos o bien empleando cruces consanguíneos (5). El huevo se comercializa principalmente en empaques de 24 huevos ($2,42 por empaque) y en conservas de 200 g ($2,5). En términos de compra, la mayoría de los consumidores expresó no adquirir el huevo de codorniz (74%), siendo el consumo esporádico aún entre quienes si lo obtienen (51,4% una vez al mes). La presentación preferida de compra es el huevo fresco empacado (46,8%), que es preparado principalmente como huevo duro hervido (66,2%). La producción y consumo de huevo de codorniz en Costa Rica se encuentra poco tecnificada y diversificada lo cual concuerda con un perfil de productores pequeños y un bajo consumo.

The Costa Rican coturniculture sector is yet in development. Production, economic or marketing aspects associated with the activity have not been previously documented in the existing literature. The objective of this study is to generate information about marketing and consumption patterns of quail eggs in Costa Rica. The investigation took place between January and December 2019 in the Greater Costa Rican Metropolitan Area. Survey was applied to 14 producers evaluating the commercial environment, while the consumption patterns of quail egg were evaluated in a sample of 300 people. Most of the producers (10) are dedicated to the exclusive production of eggs mostly in farms that do not exceed 200 birds (11), mainly housed in artisanal cages (10), where the use of production records has not been implemented (11). They essentially use poultry feed (13) without distinction of the productive stage of the bird (11), without reproductive management in six of the cases, or using consanguineous crosses (5). The egg is sold mainly in packages of 24 units ($2.42 each package) and canned 200 g ($2.5). In terms of purchase, most consumers expressed that they don´t purchase quail eggs (74%), with sporadic consumption even among those who do obtain it (51.4% once a month). When purchased, the preferred presentation the fresh packaged egg (46.8%) and is prepared mainly as hardboiled egg (66.2%). The production and consumption of quail eggs in Costa Rica is low-tech and low diversified, which is consistent with a profile of small producers and low consumption patterns., El sector coturnicultor costarricense está en proceso de desarrollo; aún no se han documentado en la literatura aspectos productivos, económicos, de mercado o comercialización asociados al mismo. El objetivo de este trabajo es generar información sobre la comercialización y el consumo del huevo de codorniz en Costa Rica. La investigación tuvo lugar entre enero y diciembre del 2019 en la Gran Área Metropolitana costarricense. Se realizaron consultas a 14 productores con respecto al entorno comercial, a la vez que se evaluaron las pautas de consumo de huevo de codorniz en una muestra de 300 personas. La mayoría de los productores (10) se dedican a la producción exclusiva de huevo en sistemas productivos que mayoritariamente no superan las 200 aves (11), principalmente alojadas en jaulas artesanales (10), y donde el uso de registros productivos no se ha implementado (11). Se emplea esencialmente alimento para gallinas de producción(13), sin distinción de la etapa productiva del ave (11), sin un manejo reproductivo en seis de los casos o bien empleando cruces consanguíneos (5). El huevo se comercializa principalmente en empaques de 24 huevos ($2,42 por empaque) y en conservas de 200 g ($2,5). En términos de compra, la mayoría de los consumidores expresó no adquirir el huevo de codorniz (74%), siendo el consumo esporádico aún entre quienes si lo obtienen (51,4% una vez al mes). La presentación preferida de compra es el huevo fresco empacado (46,8%), que es preparado principalmente como huevo duro hervido (66,2%). La producción y consumo de huevo de codorniz en Costa Rica se encuentra poco tecnificada y diversificada lo cual concuerda con un perfil de productores pequeños y un bajo consumo.

Purpose: The aim is to study the effects of stocking density on the performance characteristics, egg quality, and nutrient composition of the eggs of Japanese quails (Coturnix coturnix japonica). Study Design: Completely Randomized Design (CRD). Subjects and Methods: Two hundred and ninety-six (296) day-old sexed Japanese quails assigned to four different stocking densities (treatments) with four replicates conducted in the rainy season. The groups (I to IV) contained 11, 16, 21, and 26 quails in the approximate sex ratio of 1:1 (male: female) with stock densities 252.20 cm2, 173.43 cm2, 132.10 cm2, and 106.73 cm2/quail respectively. Standard procedures were adopted in data generation, collation and analyses. Results: The results showed significant differences (p < 0.05) in weight gain, hen-day production, hen-housed production, total egg /hen, external and internal egg parameters across the treatments. The lowest feed conversion ratio (FCR) of 2.38 % and lowest mortality (2.27 %) were obtained from group one and compared with those in groups two and three. The highest mortality rate was observed in group IV (12.50 %). The proximate analysis and mineral composition of the eggs recorded the highest values from group I which was also compared with the rest of the groups. Conclusion: It was concluded that 173.43 cm2 and 132.10 cm2/quail bird compared well with the standard (252.20 cm2/quail bird) and hence could still be adopted in quail farming without compromising their welfare and performance.

Purpose: The aim is to study the effects of stocking density on the performance characteristics, egg quality, and nutrient composition of the eggs of Japanese quails (Coturnix coturnix japonica). Study Design: Completely Randomized Design (CRD). Subjects and Methods: Two hundred and ninety-six (296) day-old sexed Japanese quails assigned to four different stocking densities (treatments) with four replicates conducted in the rainy season. The groups (I to IV) contained 11, 16, 21, and 26 quails in the approximate sex ratio of 1:1 (male: female) with stock densities 252.20 cm2, 173.43 cm2, 132.10 cm2, and 106.73 cm2/quail respectively. Standard procedures were adopted in data generation, collation and analyses. Results: The results showed significant differences (p < 0.05) in weight gain, hen-day production, hen-housed production, total egg /hen, external and internal egg parameters across the treatments. The lowest feed conversion ratio (FCR) of 2.38 % and lowest mortality (2.27 %) were obtained from group one and compared with those in groups two and three. The highest mortality rate was observed in group IV (12.50 %). The proximate analysis and mineral composition of the eggs recorded the highest values from group I which was also compared with the rest of the groups. Conclusion: It was concluded that 173.43 cm2 and 132.10 cm2/quail bird compared well with the standard (252.20 cm2/quail bird) and hence could still be adopted in quail farming without compromising their welfare and performance.

Background: Kaolin may improve quail performance by maintaining intestinal integrity and improving nutrient absorption. Objective: To evaluate the overall performance, egg quality, moisture, nitrogen and calcium content in the excreta, intestinal morphology and financial analysis of kaolin in Japanese quail feed during the production phase. Methods: A total of 192 Japanese quails, distributed in a completely randomized design with four treatments and six repetitions with eight birds each, were used. Kaolin levels added to the diet were 0, 1.5, 3.0, and 4.5%. Results: Kaolin reduced feed consumption. Additionally, egg production, feed conversion and viability increased. Moisture, nitrogen and calcium in the excreta decreased. Height and width of the intestinal villi increased with increasing levels of kaolin in the diet. Kaolin had no effect on egg quality. Inclusion level of 1.5% kaolin allowed for greater economic gains. Conclusion: Kaolin improved performance, intestinal morphology, and reduced the moisture, nitrogen and calcium contents in the excreta. Egg quality remained unchanged with the addition of kaolin, and the best economic response resulted with the addition 1.5% kaolin., Antecedentes: O caulim pode melhorar o desempenho de codornas mantendo a integridade intestinal e maior absorção de nutrientes. Objetivo: Avaliar o desempenho global, a qualidade do ovo, a umidade, o teor de nitrogênio e cálcio na excreta, a morfologia intestinal e a análise financeira do caulim em codornas japonesas durante a fase de produção. Métodos: Foram utilizadas 192 codornas japonesas, distribuídas em delineamento inteiramente casualizado, com quatro tratamentos e seis repetições, com oito aves cada. Os níveis de caulim adicionados à dieta foram 0; 1,5; 3,0; 4,5%. Resultados: O consumo de ração foi reduzido, houve melhora na porcentagem de ovos produzidos, conversão alimentar e viabilidade, os níveis de umidade, nitrogênio e cálcio nas excretas diminuíram, a altura e a largura das vilosidades intestinais aumentaram com a inclusão de níveis crescentes de caulim. Não houve efeito na qualidade do ovo. Os níveis de inclusão de 1,5% de caulim permitiram maiores ganhos econômicos. Conclusão: O caulim melhorou o desempenho, a morfologia intestinal e reduziu os teores de umidade, nitrogênio e cálcio na excreta. A qualidade dos ovos produzidos permaneceu inalterada com a adição de diferentes níveis de caulim, e o melhor nível de caulim, de acordo com a análise econômica, foi de 1,5% como aditivo para as codornas japonesas., Antecedentes: El caolín puede mejorar el rendimiento de la codorniz al mantener la integridad intestinal y una mayor absorción de nutrientes. Objetivo: Evaluar el rendimiento general, calidad del huevo, humedad, contenido de nitrógeno y calcio en la excreta, morfología intestinal, y realizar un análisis financiero de la inclusión de caolín en el alimento de codorniz japonesa durante la fase de producción. Métodos: Se utilizaron un total de 192 codornices japonesas, distribuidas en un diseño completamente al azar con cuatro tratamientos y seis repeticiones con ocho aves cada una. Los niveles de caolín agregado a la dieta fueron 0; 1,5; 3,0; y 4,5%. Resultados: El caolín redujo el consumo de alimento, hubo una mejora en el porcentaje de huevos producidos, la conversión del alimento y la viabilidad, Los niveles de humedad, nitrógeno y calcio en la excreta disminuyeron, la altura y el ancho de las vellosidades intestinales aumentaron con la inclusión de niveles crecientes de caolín. No hubo efecto sobre la calidad del huevo. Los niveles de inclusión de 1,5% de caolín permitieron mayores ganancias económicas. Conclusión: El caolín mejoró el rendimiento, la morfología intestinal y redujo los contenidos de humedad, nitrógeno y calcio en las excretas. La calidad de los huevos producidos se mantuvo sin cambios con la adición de diferentes niveles de caolín, y el mejor nivel de inclusión de caolín -según el análisis económico- fue de 1,5%.

Background: Kaolin may improve quail performance by maintaining intestinal integrity and improving nutrient absorption. Objective: To evaluate the overall performance, egg quality, moisture, nitrogen and calcium content in the excreta, intestinal morphology and financial analysis of kaolin in Japanese quail feed during the production phase. Methods: A total of 192 Japanese quails, distributed in a completely randomized design with four treatments and six repetitions with eight birds each, were used. Kaolin levels added to the diet were 0, 1.5, 3.0, and 4.5%. Results: Kaolin reduced feed consumption. Additionally, egg production, feed conversion and viability increased. Moisture, nitrogen and calcium in the excreta decreased. Height and width of the intestinal villi increased with increasing levels of kaolin in the diet. Kaolin had no effect on egg quality. Inclusion level of 1.5% kaolin allowed for greater economic gains. Conclusion: Kaolin improved performance, intestinal morphology, and reduced the moisture, nitrogen and calcium contents in the excreta. Egg quality remained unchanged with the addition of kaolin, and the best economic response resulted with the addition 1.5% kaolin., Antecedentes: O caulim pode melhorar o desempenho de codornas mantendo a integridade intestinal e maior absorção de nutrientes. Objetivo: Avaliar o desempenho global, a qualidade do ovo, a umidade, o teor de nitrogênio e cálcio na excreta, a morfologia intestinal e a análise financeira do caulim em codornas japonesas durante a fase de produção. Métodos: Foram utilizadas 192 codornas japonesas, distribuídas em delineamento inteiramente casualizado, com quatro tratamentos e seis repetições, com oito aves cada. Os níveis de caulim adicionados à dieta foram 0; 1,5; 3,0; 4,5%. Resultados: O consumo de ração foi reduzido, houve melhora na porcentagem de ovos produzidos, conversão alimentar e viabilidade, os níveis de umidade, nitrogênio e cálcio nas excretas diminuíram, a altura e a largura das vilosidades intestinais aumentaram com a inclusão de níveis crescentes de caulim. Não houve efeito na qualidade do ovo. Os níveis de inclusão de 1,5% de caulim permitiram maiores ganhos econômicos. Conclusão: O caulim melhorou o desempenho, a morfologia intestinal e reduziu os teores de umidade, nitrogênio e cálcio na excreta. A qualidade dos ovos produzidos permaneceu inalterada com a adição de diferentes níveis de caulim, e o melhor nível de caulim, de acordo com a análise econômica, foi de 1,5% como aditivo para as codornas japonesas., Antecedentes: El caolín puede mejorar el rendimiento de la codorniz al mantener la integridad intestinal y una mayor absorción de nutrientes. Objetivo: Evaluar el rendimiento general, calidad del huevo, humedad, contenido de nitrógeno y calcio en la excreta, morfología intestinal, y realizar un análisis financiero de la inclusión de caolín en el alimento de codorniz japonesa durante la fase de producción. Métodos: Se utilizaron un total de 192 codornices japonesas, distribuidas en un diseño completamente al azar con cuatro tratamientos y seis repeticiones con ocho aves cada una. Los niveles de caolín agregado a la dieta fueron 0; 1,5; 3,0; y 4,5%. Resultados: El caolín redujo el consumo de alimento, hubo una mejora en el porcentaje de huevos producidos, la conversión del alimento y la viabilidad, Los niveles de humedad, nitrógeno y calcio en la excreta disminuyeron, la altura y el ancho de las vellosidades intestinales aumentaron con la inclusión de niveles crecientes de caolín. No hubo efecto sobre la calidad del huevo. Los niveles de inclusión de 1,5% de caolín permitieron mayores ganancias económicas. Conclusión: El caolín mejoró el rendimiento, la morfología intestinal y redujo los contenidos de humedad, nitrógeno y calcio en las excretas. La calidad de los huevos producidos se mantuvo sin cambios con la adición de diferentes niveles de caolín, y el mejor nivel de inclusión de caolín -según el análisis económico- fue de 1,5%.

This work investigates laying performances and egg quality of 200 quails during 266 laying days. The first collected 240 eggs, for the periods: 12, 16, 20, 24, 28, 32, 36, 40, 44 weeks were used in this study. The average laying rate calculated over a period of 37 weeks is 74.44 %. All studied eggs quality parameters were significantly (p<0.001) influenced by the age of the quail. The average weight of the whole egg (13.66 g), yolk (3.99 g) and shell (2.28 g) reach their maximum value at the 40 th week. The maximum albumen average weight (7.45 g) was observed at 32 nd week. Albumen (12.02) and yolk (48.72) indices recorded their highest values at the 12 th and the 16 th weeks, respectively. The eggs freshness, expressed here by Haugh units decreased with age. They range from 89.56 at the 12 th week to 83.71 at the 44 th week of age. Yolk color registered values with irregular fluctuations (7.12 to 9.33) in a colorimetric scale of 15 ladders. Highly significant and positive correlations (p<0.001) and were recorded between the whole egg weight and the weight of albumen, yolk and shell. To conclude, the quail age affects significantly the various egg quality parameters., Le présent travail propose une évaluation des performances de ponte et de la qualité des œufs de cailles. Pour cette étude, les oeufs de 200 cailles ont été récoltés toutes les 4 semaines à partir de la 12 ème semaine d'âge jusque la 44 ème semaine d'âge. Pour chaque période de récolte, les 240 premiers oeufs ont été pris en compte. Le taux de ponte moyen calculé sur une période de 37 semaines est de 74,44 %. Tous les paramètres de qualité d'oeufs étudiés ont été significativement (p<0,001) influencés par l'âge des cailles. Les poids moyens de l'œuf entier (13,66 g), du jaune (3,99 g) et de la coquille (2,28 g) atteignent leurs valeurs maximales à la 40 ème semaine. Le poids moyen du blanc arrive à sa valeur maximale de 7,45 gr à la 32 ème semaine. Les indices du blanc (12,02) et du jaune (48,72) ont présenté leurs valeurs maximales respectivement à la 12 ème et à la 16 ème semaine d'âge. La fraicheur des oeufs, ex- primée par les unités d'Haugh diminue avec l'âge. Elle passe de 89,56 Unités d'Haugh (UH) à la 12 ème semaine d'âge à 83,71 UH à la 44 ème semaine d'âge. La couleur du jaune présente des valeurs avec des fluctuations irrégulières (7,12 à 9,33) selon une échelle colorimétrique de 15 échelles (l'éventail DSM de couleurs du jaune de l'oeuf). En conclusion, l'âge influence significativement les différents paramètres de qualité de l'oeuf de caille.

This work investigates laying performances and egg quality of 200 quails during 266 laying days. The first collected 240 eggs, for the periods: 12, 16, 20, 24, 28, 32, 36, 40, 44 weeks were used in this study. The average laying rate calculated over a period of 37 weeks is 74.44 %. All studied eggs quality parameters were significantly (p<0.001) influenced by the age of the quail. The average weight of the whole egg (13.66 g), yolk (3.99 g) and shell (2.28 g) reach their maximum value at the 40 th week. The maximum albumen average weight (7.45 g) was observed at 32 nd week. Albumen (12.02) and yolk (48.72) indices recorded their highest values at the 12 th and the 16 th weeks, respectively. The eggs freshness, expressed here by Haugh units decreased with age. They range from 89.56 at the 12 th week to 83.71 at the 44 th week of age. Yolk color registered values with irregular fluctuations (7.12 to 9.33) in a colorimetric scale of 15 ladders. Highly significant and positive correlations (p<0.001) and were recorded between the whole egg weight and the weight of albumen, yolk and shell. To conclude, the quail age affects significantly the various egg quality parameters., Le présent travail propose une évaluation des performances de ponte et de la qualité des œufs de cailles. Pour cette étude, les oeufs de 200 cailles ont été récoltés toutes les 4 semaines à partir de la 12 ème semaine d'âge jusque la 44 ème semaine d'âge. Pour chaque période de récolte, les 240 premiers oeufs ont été pris en compte. Le taux de ponte moyen calculé sur une période de 37 semaines est de 74,44 %. Tous les paramètres de qualité d'oeufs étudiés ont été significativement (p<0,001) influencés par l'âge des cailles. Les poids moyens de l'œuf entier (13,66 g), du jaune (3,99 g) et de la coquille (2,28 g) atteignent leurs valeurs maximales à la 40 ème semaine. Le poids moyen du blanc arrive à sa valeur maximale de 7,45 gr à la 32 ème semaine. Les indices du blanc (12,02) et du jaune (48,72) ont présenté leurs valeurs maximales respectivement à la 12 ème et à la 16 ème semaine d'âge. La fraicheur des oeufs, ex- primée par les unités d'Haugh diminue avec l'âge. Elle passe de 89,56 Unités d'Haugh (UH) à la 12 ème semaine d'âge à 83,71 UH à la 44 ème semaine d'âge. La couleur du jaune présente des valeurs avec des fluctuations irrégulières (7,12 à 9,33) selon une échelle colorimétrique de 15 échelles (l'éventail DSM de couleurs du jaune de l'oeuf). En conclusion, l'âge influence significativement les différents paramètres de qualité de l'oeuf de caille.

Tendo-se o objetivo de avaliar o desempenho, o rendimento de carcaça e a composição química da carne de codornas japonesas macho submetidas a diferentes níveis de energia e proteína na dieta, 216 codornas foram distribuídas em nove tratamentos, quatro repetições e seis aves por parcela. Aos 38 dias de idade as aves foram distribuídas em delineamento inteiramente casualizado, em esquema fatorial 3 x 3, sendo três níveis de energia (2.600, 2.800 e 3.000 kcal EM/kg) e três níveis de proteína (16, 18 e 20%), constituindo as rações experimentais fornecidas até 56 dias de idade. Os resultados mostraram que a matéria seca original foi significativamente mais elevada na carne das aves submetidas ao tratamento contendo 2.600 kcal EM/kg de ração seguida pela carne das aves alimentadas com 3.000 kcal EM/kg. A quantidade de lipídios totais também foi maior na carne das aves alimentadas com rações contendo 2.600 e 3.000 kcal EM/kg de ração. Não houve influência dos níveis de energia e proteína das dietas nos parâmetros de desempenho e qualidade de carne. Conclui-se que os menores níveis de energia e de proteína na dieta não afetaram o desempenho, o rendimento de carcaça e a composição química da carne de codornas machos para postura.

Study on newly laid eggs of Japanese quail Coturnix coturnix japonica was undertaken for a period of 18 days on incubation in controlled laboratory conditions. The aim of the study was to evaluate the changes in egg weight, shell weight, yolk weight and embryo weight throughout the period of incubation. It had been found that as the embryo grows, the egg weight slowly goes down while embryo weight goes on increasing day by day. The study inferred that the shift or reduction in weight of egg is attributable to the progressive growth of embryo which utilizes its yolk contents for its growth. Apart from this, the shell weight also reduced from first day to last day in order to facilitate hatching of the embryo.

Stress responses involve activation of the hypothalamo-pituitary-adrenal (HPA) axis and the secretion of glucocorticoid hormones, and can help animals cope with changes in their environments. Corticosterone is the primary glucocorticoid in birds and has metabolic actions, and can affect behaviour and reproduction. Stimuli that activate the HPA axis are called stressors, and stressors can be classified as either physical or emotional. When animals respond to emotional stressors they also experience fear, and the magnitude of a corticosterone response to an emotional stressor is thought to be related to the degree of fearfulness that is experienced by a bird. The great majority of studies have measured plasma corticosterone responses of birds to emotional rather than physical stressors, and corticosterone responses to emotional stressors are assumed to reflect the responsiveness of the HPA axis of birds to stressors in general. The aims of the research described in this thesis were to determine the effects of corticosterone on fear behaviour, reproductive function, and plasma corticosterone responses to stressors in Japanese quail (Coturnix coturnix japonica), both during and after treatment, and to examine if plasma corticosterone responses to similar emotional stressors, and to different types of emotional and physical stressors are related in individual quail. Plasma corticosterone concentrations were significantly higher in quail treated with corticosterone in their drinking water compared with controls during a 21 day treatment period, and concentrations remained elevated eight days after treatment ended. Corticosterone had little or no effect on the fearfulness of quail in tonic immobility, novel object or open field tests of fear behaviour. Body weight, food intake, egg production and egg weight were significantly lower in some corticosterone treatment groups than in controls during treatment and for up to 22 days after treatment ended. Corticosterone concentra

Foram realizados dois experimentos para se determinar as exigências de cálcio para melhor desempenho e deposição de cálcio (Ca) e fósforo (P) na tíbia e no fêmur de codornas japonesas, no período de um a 35 dias de idade. Utilizaram-se, em cada experimento, 210 codornas fêmeas, distribuídas num delineamento experimental inteiramente casualizado, constituído de sete tratamentos, com três repetições e dez aves por unidade experimental. Os tratamentos consistiram numa ração basal suplementada com calcário calcítico para atingir os níveis de 0,85; 1,00; 1,15; 1,30; 1,45; 1,60 e 1,75% de Capara a fase inicial (1 a 21 dias) e de 0,53; 0,68; 0,83; 0,98; 1,13; 1,28 e 1,43% de Ca para a fase de crescimento (22 a 35 dias). Foi verificado efeito quadrático dos níveis de Ca da dieta sobre o consumo de ração, o ganho de peso e a conversão alimentar na fase inicial, bem como sobre o teor de Ca na tíbia e no fêmur das codornas aos 21 dias de idade. Na fase de crescimento, apenas a conversão alimentar foi influenciada pelos níveis de Ca da dieta. Recomendam-se 1,26 e 0,87% de Ca nas dietas para codornas nas fases inicial e decrescimento, respectivamente. Two trials were carried out to determine calcium requirements for better performance, and calcium (Ca) and phosphorus (P) deposition in the tibia and femur of Japanese quails aged 1 to 35 days. Two hundred and ten female quails were allocated in a completely randomizedexperimental design, with seven treatments, three repetitions and ten birds per experimental unit. The treatments consisted of a basal diet supplemented with limestone in order to produce the following Ca levels: 0.85; 1.00; 1.15; 1.30; 1.45; 1.60 and 1.75% in the initialphase (1 to 21 days) and 0.53; 0.68; 0.83; 0.98; 1.13; 1.28 and 1.43% in the growing phase (22 to 35 days). In the initial phase, feed intake, weight gain and feed conversion showed quadratic response to dietary Ca levels, as well as on the content of Ca in the tibia andfemur of quails. In the

O epidídimo em aves é uma estrutura de importância no transporte e estágios do metabolismo de espermatozóides. Investigou-se a ultra-estrutura do epidídimo nos segmentos cranial, médio e caudal de 10 codornas Coturnix coturnix japonica sexualmente maduras, através da microscopia eletrônica de varredura e não foram observadas distinções nestes segmentos. Analisando-se todas as porções do epidídimo, observou-se um epitélio de revestimento e estroma peritubular, além de espermatozóides entre os estereocílios.

O epidídimo em aves é uma estrutura de importância no transporte e estágios do metabolismo de espermatozóides. Investigou-se a ultra-estrutura do epidídimo nos segmentos cranial, médio e caudal de 10 codornas Coturnix coturnix japonica sexualmente maduras, através da microscopia eletrônica de varredura e não foram observadas distinções nestes segmentos. Analisando-se todas as porções do epidídimo, observou-se um epitélio de revestimento e estroma peritubular, além de espermatozóides entre os estereocílios.

O epidídimo em aves é uma estrutura de importância no transporte e estágios do metabolismo de espermatozóides. Investigou-se a ultra-estrutura do epidídimo nos segmentos cranial, médio e caudal de 10 codornas Coturnix coturnix japonica sexualmente maduras, através da microscopia eletrônica de varredura e não foram observadas distinções nestes segmentos. Analisando-se todas as porções do epidídimo, observou-se um epitélio de revestimento e estroma peritubular, além de espermatozóides entre os estereocílios.

O epidídimo em aves é uma estrutura de importância no transporte e estágios do metabolismo de espermatozóides. Investigou-se a ultra-estrutura do epidídimo nos segmentos cranial, médio e caudal de 10 codornas Coturnix coturnix japonica sexualmente maduras, através da microscopia eletrônica de varredura e não foram observadas distinções nestes segmentos. Analisando-se todas as porções do epidídimo, observou-se um epitélio de revestimento e estroma peritubular, além de espermatozóides entre os estereocílios.

O epidídimo em aves é uma estrutura de importância no transporte e estágios do metabolismo de espermatozóides. Investigou-se a ultra-estrutura do epidídimo nos segmentos cranial, médio e caudal de 10 codornas Coturnix coturnix japonica sexualmente maduras, através da microscopia eletrônica de varredura e não foram observadas distinções nestes segmentos. Analisando-se todas as porções do epidídimo, observou-se um epitélio de revestimento e estroma peritubular, além de espermatozóides entre os estereocílios.

Corticosterone is the major adrenal glucocorticoid in birds. It is secreted in response to stressors, with plasma concentrations typically rising to a peak within 10 to 15 minutes and then declining over 30 to 60 minutes once the stressor is removed. The increase in corticosterone is thought to help the animal to adjust to the stressor, although corticosterone may also inhibit the reproductive axis. The corticosterone response to a stressor varies between individuals, although the level of the hypothalamic-pituitary-adrenal axis at which this variation arises in birds has not been identified. The goals of this research were to determine in Japanese quail (Coturnix coturnix japonica): (1) the effects of corticosterone and of various stressors on sex steroid secretion; (2) corticosterone responses to 5, 10 or 15 min exposure to manual restraint and 15 min exposure to different stimuli; (3) quantifying individual variation in the corticosterone response; and (4) whether individual variation in the corticosterone response to stimuli used in goal 2 is regulated by differences in pituitary or adrenal sensitivity to corticotropin releasing factor (CRF) and adrenocorticotropic hormone (ACTH) respectively. A prolonged elevation in plasma corticosterone concentrations can inhibit reproduction. The effects of a short elevation in corticosterone are less understood, so the relationship between corticosterone and sex steroid secretion in quail was characterised by administering 1.2 mg corticosterone injections. Corticosterone treatment stimulated an increase in plasma corticosterone, while testosterone declined in both corticosterone-treated and control birds. Plasma LH was unaffected by challenge with corticosterone. Collectively, these data suggest that repeated handling associated with frequent blood sampling inhibited testosterone secretion directly at the testis. Corticosterone responses to a variety of novel stimuli were characterised. Manual restraint for 10 or 15 min cau

These studies examined the effects of corticosterone on the reproductive system, investigated the relationship between plasma and faecal corticosterone levels and defined corticosterones response to handling in the Japanese quail (Coturnix coturnix japonica). Six days of daily corticosterone injections decreased the area of the cloacal protuberance in both seven week old and six month old male quail. However, plasma testosterone levels 24 hours after an injection were only decreased in the six month old birds. There was a strong correlation between basal plasma and faecal corticosterone concentrations in the six month old birds. The effects of corticosterone during the 24 hours after an injection were then examined before and after six days of corticosterone injections in male quail. Corticosterone injections decreased plasma testosterone levels three-fold for 6-12 hours both after a single corticosterone injection and after six days of treatment. However, there were no changes in plasma luteinising hormone levels during the 24 hours after an injection. This result is consistent with corticosterone acting directly on the testes to decrease testosterone release. The rate of corticosterone removal from the blood after an injection increased after six days of corticosterone injections. Handling female Japanese quail for 15 minutes resulted in increased plasma corticosterone levels for less than 30 minutes. Mean corticosterone response curves were almost identical when the same birds were handled on three occasions. Although corticosterone response curves were similar during the early afternoon and during the night, basal corticosterone levels and the area under the corticosterone response curves were lower at night. Plasma corticosterone levels 0 and 15 minutes after the initiation of handling were more than twice as high in birds with large gonads than birds with small gonads. This study provides the first information in birds of a decrease in plasma testosterone leve