RESUMO

Eggshell quality is directly linked to the good acceptability of the product by consumers, whereas the industry is concerned with economic losses. Prolonged periods of laying, diseases, nutrition, bird age and genetics can influence egg quality. This study aimed to examine the influence of the environment, bird age and storage period on the physical characteristics of the shell of eggs from commercial laying hens. The experiment involved 288 eggs from Hy-line hens, which were distributed in a completely randomized design with a triple 3×2×4 factorial arrangement represented by three ages (31, 62 or 88 weeks), two storage temperatures (ambient or refrigerated), and four storage periods (one, 10, 20 or 30 days), totaling 24 treatments. Four replications were used with three eggs each. Eggshell strength, percentage and thickness were measured. Differences were observed, with the eggs stored at room temperature exhibiting lower shell strength. Laying eggs at an advanced age (88 weeks) resulted in decreased eggshell strength as compared with the other ages, whereas the eggs from young layers (31 weeks) had a thicker shell. The advancing age of the laying hens reduced eggshell quality, regardless of the storage environment. Nonetheless, the eggs stored in the refrigerator showed better eggshell quality and integrity than those stored at ambient temperature.(AU)

A qualidade da casca está diretamente ligada à boa aceitabilidade do produto pelos consumidores, enquanto a indústria se preocupa com as perdas econômicas. Períodos prolongados de postura, doenças, nutrição, idade da ave e genética podem influenciar a qualidade dos ovos. Objetivou-se avaliar a influência do ambiente, idade da ave e período de armazenamento nas características físicas da casca de ovos de poedeiras comerciais. Foram utilizados 288 ovos de poedeiras Hy-line, distribuídos em um delineamento inteiramente casualizado em fatorial triplo 3x2x4, sendo os fatores: três idades (31, 62 e 88 semanas), temperatura de armazenamento (ambiente e refrigerado), e quatro períodos de armazenamento (um, 10, 20 e 30 dias), totalizando 24 tratamentos, com quatro repetições de três ovos. Avaliou-se a resistência, percentual e espessura da casca. Foram observadas diferenças, uma vez que os ovos armazenados em temperatura ambiente apresentaram diminuição na resistência de casca. Ovos de poedeiras em idade avançada (88 semanas) apresentaram pior resistência de casca em relação às demais idades, enquanto ovos provenientes de poedeiras jovens (31 semanas) apresentaram maior espessura de casca. A idade avançada da poedeira reduziu a qualidade de casca dos ovos, independentemente do ambiente de armazenamento. Ainda, os ovos armazenados em geladeira apresentaram melhor qualidade e integridade da casca em comparação com os armazenados ao ambiente.(AU)

Assuntos

RESUMO

ABSTRACT: Eggshell quality is directly linked to the good acceptability of the product by consumers, whereas the industry is concerned with economic losses. Prolonged periods of laying, diseases, nutrition, bird age and genetics can influence egg quality. This study aimed to examine the influence of the environment, bird age and storage period on the physical characteristics of the shell of eggs from commercial laying hens. The experiment involved 288 eggs from Hy-line hens, which were distributed in a completely randomized design with a triple 3×2×4 factorial arrangement represented by three ages (31, 62 or 88 weeks), two storage temperatures (ambient or refrigerated), and four storage periods (one, 10, 20 or 30 days), totaling 24 treatments. Four replications were used with three eggs each. Eggshell strength, percentage and thickness were measured. Differences were observed, with the eggs stored at room temperature exhibiting lower shell strength. Laying eggs at an advanced age (88 weeks) resulted in decreased eggshell strength as compared with the other ages, whereas the eggs from young layers (31 weeks) had a thicker shell. The advancing age of the laying hens reduced eggshell quality, regardless of the storage environment. Nonetheless, the eggs stored in the refrigerator showed better eggshell quality and integrity than those stored at ambient temperature.

RESUMO: A qualidade da casca está diretamente ligada à boa aceitabilidade do produto pelos consumidores, enquanto a indústria se preocupa com as perdas econômicas. Períodos prolongados de postura, doenças, nutrição, idade da ave e genética podem influenciar a qualidade dos ovos. Objetivou-se avaliar a influência do ambiente, idade da ave e período de armazenamento nas características físicas da casca de ovos de poedeiras comerciais. Foram utilizados 288 ovos de poedeiras Hy-line, distribuídos em um delineamento inteiramente casualizado em fatorial triplo 3x2x4, sendo os fatores: três idades (31, 62 e 88 semanas), temperatura de armazenamento (ambiente e refrigerado), e quatro períodos de armazenamento (um, 10, 20 e 30 dias), totalizando 24 tratamentos, com quatro repetições de três ovos. Avaliou-se a resistência, percentual e espessura da casca. Foram observadas diferenças, uma vez que os ovos armazenados em temperatura ambiente apresentaram diminuição na resistência de casca. Ovos de poedeiras em idade avançada (88 semanas) apresentaram pior resistência de casca em relação às demais idades, enquanto ovos provenientes de poedeiras jovens (31 semanas) apresentaram maior espessura de casca. A idade avançada da poedeira reduziu a qualidade de casca dos ovos, independentemente do ambiente de armazenamento. Ainda, os ovos armazenados em geladeira apresentaram melhor qualidade e integridade da casca em comparação com os armazenados ao ambiente.

RESUMO

The objective of this study was to assess the effect of ambient temperature (T) and feeding time (FT) on eggshell thickness (ST) and egg weight (EW) of broiler breeder hens. Thirty 44-week-old Ross 308 broiler breeder hens were randomly distributed into six environmentally controlled chambers and kept in individual cages. Three thermal treatments were applied: 20 ºC (T1), cyclic 20-30 ºC (30 °C between 1000 h and 1800 h) (T2), and 30 ºC (T3). Birds received 180 g of commercial breeder food at 0730 h (FT1) or 1530 h (FT2). There were two replications per treatment and egg collection was performed for seven days. The eggs from the birds at T1 and T2 fed at 1530 h (T1FT2 and T2FT2 respectively) were significantly heavier than those laid by hens at the same T when fed in the morning (T1FT1 and T2FT1); eggs from T1FT1 and T2FT1 were heavier than the eggs from T3, but there were no significant differences between them. Both T and FT had significant effects on ST, but no significant interactions were found. Birds fed at 1530 h had the highest ST, whilst birds at T3 showed the lowest. Birds on T2 produced the thickest shells due to a higher ST in birds fed at 1530 h. Birds fed at 1530 h consumed their food between 1800 h and 2030 h, resulting in a higher dietary Ca2 + available during shell mineralization. The effect of FT and biphasic T treatments on ST in feed restricted broiler breeders should be interpreted considering the length of the high T phase to the actual food consumption time.(AU)

Assuntos

RESUMO

Eggshell quality is directly linked to the good acceptability of the product by consumers, whereas the industry is concerned with economic losses. Prolonged periods of laying, diseases, nutrition, bird age and genetics can influence egg quality. This study aimed to examine the influence of the environment, bird age and storage period on the physical characteristics of the shell of eggs from commercial laying hens. The experiment involved 288 eggs from Hy-line hens, which were distributed in a completely randomized design with a triple 3×2×4 factorial arrangement represented by three ages (31, 62 or 88 weeks), two storage temperatures (ambient or refrigerated), and four storage periods (one, 10, 20 or 30 days), totaling 24 treatments. Four replications were used with three eggs each. Eggshell strength, percentage and thickness were measured. Differences were observed, with the eggs stored at room temperature exhibiting lower shell strength. Laying eggs at an advanced age (88 weeks) resulted in decreased eggshell strength as compared with the other ages, whereas the eggs from young layers (31 weeks) had a thicker shell. The advancing age of the laying hens reduced eggshell quality, regardless of the storage environment. Nonetheless, the eggs stored in the refrigerator showed better eggshell quality and integrity than those stored at ambient temperature.

A qualidade da casca está diretamente ligada à boa aceitabilidade do produto pelos consumidores, enquanto a indústria se preocupa com as perdas econômicas. Períodos prolongados de postura, doenças, nutrição, idade da ave e genética podem influenciar a qualidade dos ovos. Objetivou-se avaliar a influência do ambiente, idade da ave e período de armazenamento nas características físicas da casca de ovos de poedeiras comerciais. Foram utilizados 288 ovos de poedeiras Hy-line, distribuídos em um delineamento inteiramente casualizado em fatorial triplo 3x2x4, sendo os fatores: três idades (31, 62 e 88 semanas), temperatura de armazenamento (ambiente e refrigerado), e quatro períodos de armazenamento (um, 10, 20 e 30 dias), totalizando 24 tratamentos, com quatro repetições de três ovos. Avaliou-se a resistência, percentual e espessura da casca. Foram observadas diferenças, uma vez que os ovos armazenados em temperatura ambiente apresentaram diminuição na resistência de casca. Ovos de poedeiras em idade avançada (88 semanas) apresentaram pior resistência de casca em relação às demais idades, enquanto ovos provenientes de poedeiras jovens (31 semanas) apresentaram maior espessura de casca. A idade avançada da poedeira reduziu a qualidade de casca dos ovos, independentemente do ambiente de armazenamento. Ainda, os ovos armazenados em geladeira apresentaram melhor qualidade e integridade da casca em comparação com os armazenados ao ambiente.

Assuntos

RESUMO

Evolved eggshell strength is greater in several lineages of obligate avian brood parasites (birds that lay their eggs in other species' nests) than in their hosts. Greater strength is typically indirectly implied by eggshell thickness comparisons between parasites and hosts. Nevertheless, there is strong evidence that the eggshell structural organization differentially influences its mechanical properties. Using instrumental puncture tests and SEM/EBSD and XRD techniques, we studied the most relevant eggshell mechanical, textural, ultrastructural and microstructural features between several host species and their parasitic cowbirds (Molothrus spp.). These parasitic species display different egg-destructive behaviors, reducing host reproductive fitness, including the more frequently host-egg puncturing M. rufoaxillaris and M. bonariensis, and the host egg-removing M. ater. The results, analyzed using a phylogenetic comparative approach, showed interspecific patterns in the mechanical and structural features. Overall, the eggshells of the two egg-puncturing parasites (but not of M. ater) were stronger, stiffer and required greater stress to produce a fracture than the respective hosts' eggs. These features were affected by eggshell microstructure and ultrastructure, related to the increase in the intercrystalline boundary network acting in cooperation with the increase in palisade layer thickness. Both structural features generate more options and greater lengths of intercrystalline paths, increasing the energy consumed in crack or fissure propagation. The reported patterns of all these diverse eggshell features support a new set of interpretations, confirming several hypotheses regarding the impact of the two reproductive strategies (parasitic versus parental) and parasitic egg destruction behaviors (more versus less frequently puncturing).

Assuntos

RESUMO

Sixty fresh hen eggs and 60 quail eggs were used in an experiment conducted at UFRRJ in order to survey the correlation between the eggshell quality measurements by average of the following parameters: specific gravity, breaking strength, percentage and thickness of the shell. For hen eggs, specific gravity demonstrated a higher correlation (p 0.05) between specific gravity with the other shell quality analyses. There was a correspondence between breaking strength with the percentage and the thickness of the shell, this ratio was higher for the percentage of shell. For hen eggs, the measurement of the specific gravity method used in commercial poultry farms was adequate to indicate good shell quality in accordance with great correlation with shell thickness. However, the evaluation of shell quality through the specific gravity for quail eggs needs adaptation in the methodology for egg morphology for this species. The parameters of shell quality surveyed: specific gravity, breaking resistance, percentage of shell and thickness of shell in hen eggs showed a positive correlation to a moderate degree (0.54). For quail eggs, the shell percentage shows moderate match (0.60) only with breaking strength and shell thickness.

Utilizou-se 60 ovos de galinhas e 60 ovos de codornas frescos, em um experimento conduzido na UFRRJ a fim de analisar a correlação entre as medidas de qualidade da casca ovos por meio dos seguintes parâmetros: gravidade específica, resistência à quebra, porcentagem e espessura da casca. Para os ovos de galinha, a gravidade específica demonstrou maior correlação (p 0,05) entre a gravidade específica com as outras análises de qualidade de casca. Houve correspondência entre a resistência à quebra com a porcentagem e a espessura da casca, sendo essa relação maior para a porcentagem de casca. Para ovos de galinha, a mensuração do método da gravidade especifica utilizado em granjas comerciais, é adequado para indicar boa qualidade de casca em função da maior correlação com a espessura da casca. Contudo, a avaliação da qualidade da casca através da gravidade específica para ovos de codorna necessita de adaptação na metodologia para a morfologia dos ovos dessa espécie. Os parâmetros de qualidade de casca analisados: gravidade específica, resistência a quebra dos ovos, porcentagem de casca e espessura da casca em ovos de galinha apresentam correlação positiva com grau moderado (0,54). Para ovos de codorna, a porcentagem de casca apresenta correspondência moderada (0,60) somente com resistência à quebra e espessura da casca.

Assuntos

RESUMO

For a long time, it has been said that eggshell quality decreases as eggs increase in size, but this increase is seen as the breeder age advances. Therefore, the present study aimed to evaluate the age and egg weight effect on Cobb 500 broiler breeders on eggshell quality. The quality measures tested were eggshell and mineral matter percentage, eggshell surface, shape and eggshell index, eggshell and membrane thickness and specific gravity. Eggs from 27, 31, 36, 40, 46, 48, 53, 58 and 63 week-old breeders were classified as eggs with a constant weight ranging from 63.8 ± 0.2; and eggs with increasing weight, according to age, being: 55.8g; 60g; 62.2g; 64.2g; 65.2g, 66.6g, 68.1g, 69.9g and 72.5g, respectively. The eggs weight did not influence the eggshell percentage and the specific gravity in seven of the nine tested ages, while for mineral matter in six of the nine studied ages. The shape and shell index, shell and membrane thickness are characteristics independent of egg weight. As the Cobb 500 broiler breeder age advanced, the mineral matter concentration and specific gravity maintained constant, the membrane thickness (R2>70) reduced, and other studied variables were influenced in the same way for both treatments. Thus, the eggshell quality decrease with the advancing age cannot be attributed solely to the increase of egg weight with consequent increase in the eggshell volume and the surface, but there are also age-related factors.

Assuntos

RESUMO

For a long time, it has been said that eggshell quality decreases as eggs increase in size, but this increase is seen as the breeder age advances. Therefore, the present study aimed to evaluate the age and egg weight effect on Cobb 500 broiler breeders on eggshell quality. The quality measures tested were eggshell and mineral matter percentage, eggshell surface, shape and eggshell index, eggshell and membrane thickness and specific gravity. Eggs from 27, 31, 36, 40, 46, 48, 53, 58 and 63 week-old breeders were classified as eggs with a constant weight ranging from 63.8 ± 0.2; and eggs with increasing weight, according to age, being: 55.8g; 60g; 62.2g; 64.2g; 65.2g, 66.6g, 68.1g, 69.9g and 72.5g, respectively. The eggs weight did not influence the eggshell percentage and the specific gravity in seven of the nine tested ages, while for mineral matter in six of the nine studied ages. The shape and shell index, shell and membrane thickness are characteristics independent of egg weight. As the Cobb 500 broiler breeder age advanced, the mineral matter concentration and specific gravity maintained constant, the membrane thickness (R2>70) reduced, and other studied variables were influenced in the same way for both treatments. Thus, the eggshell quality decrease with the advancing age cannot be attributed solely to the increase of egg weight with consequent increase in the eggshell volume and the surface, but there are also age-related factors.(AU)

Assuntos

RESUMO

Sixty fresh hen eggs and 60 quail eggs were used in an experiment conducted at UFRRJ in order to survey the correlation between the eggshell quality measurements by average of the following parameters: specific gravity, breaking strength, percentage and thickness of the shell. For hen eggs, specific gravity demonstrated a higher correlation (p <0.05) with shell thickness as compared to other methodologies; the breaking strength correlated with the shell percentage and shell thickness. In quail eggs, there was no correlation (p> 0.05) between specific gravity with the other shell quality analyses. There was a correspondence between breaking strength with the percentage and the thickness of the shell, this ratio was higher for the percentage of shell. For hen eggs, the measurement of the specific gravity method used in commercial poultry farms was adequate to indicate good shell quality in accordance with great correlation with shell thickness. However, the evaluation of shell quality through the specific gravity for quail eggs needs adaptation in the methodology for egg morphology for this species. The parameters of shell quality surveyed: specific gravity, breaking resistance, percentage of shell and thickness of shell in hen eggs showed a positive correlation to a moderate degree (0.54). For quail eggs, the shell percentage shows moderate match (0.60) only with breaking strength and shell thickness.(AU)

Utilizou-se 60 ovos de galinhas e 60 ovos de codornas frescos, em um experimento conduzido na UFRRJ a fim de analisar a correlação entre as medidas de qualidade da casca ovos por meio dos seguintes parâmetros: gravidade específica, resistência à quebra, porcentagem e espessura da casca. Para os ovos de galinha, a gravidade específica demonstrou maior correlação (p <0,05) com a espessura da casca em comparação com as outras metodologias; a resistência à quebra se correlacionou com a porcentagem de casca e este parâmetro com a espessura da casca. Em ovos de codorna, não houve correlação (p >0,05) entre a gravidade específica com as outras análises de qualidade de casca. Houve correspondência entre a resistência à quebra com a porcentagem e a espessura da casca, sendo essa relação maior para a porcentagem de casca. Para ovos de galinha, a mensuração do método da gravidade especifica utilizado em granjas comerciais, é adequado para indicar boa qualidade de casca em função da maior correlação com a espessura da casca. Contudo, a avaliação da qualidade da casca através da gravidade específica para ovos de codorna necessita de adaptação na metodologia para a morfologia dos ovos dessa espécie. Os parâmetros de qualidade de casca analisados: gravidade específica, resistência a quebra dos ovos, porcentagem de casca e espessura da casca em ovos de galinha apresentam correlação positiva com grau moderado (0,54). Para ovos de codorna, a porcentagem de casca apresenta correspondência moderada (0,60) somente com resistência à quebra e espessura da casca.(AU)

Assuntos

RESUMO

In order to evaluate the performance and egg quality of quails on different time feeding, One hundred ninety two Japanese quail (Coturnix coturnix japonica) at 24 weeks of age were distributed in a completely randomized design with two replications and twelve treatments eight birds each. The treatments consisted of two different times of feeding at 6h and 16h. The performance was evaluated by the feed intake (g/bird/day), egg production (%), egg mass (g), feed conversion per egg mass (kg/kg ), feed conversion per dozen eggs (kg/dz) and viability (%). The egg quality was evaluated by the eggshell thickness (mm), percentage of albumen, yolk percentage and average egg weight (g). The feeding time at 16h favored the performance of Japanese quails at 26 and 34 wk of age considering egg production, egg mass and average egg weight. Thus, it is recommended to feed the quails at times that coincide with the highest egg laying intensity, which ranges from 16 to 19h.

Com o objetivo de avaliar o desempenho e a qualidade de ovos de codornas arraçoadas em diferentes horários na produção, foram utilizadas 192 codornas japonesas com 24 semanas de idade, distribuídas em um delineamento inteiramente casualizado com dois tratamentos e doze repetições de oito aves cada. Os tratamentos corresponderam a dois horários de arraçoamento: 6:00h e 16:00h. Para o desempenho foram avaliados: consumo de ração (g/ave/dia), produção de ovos (%), massa de ovos (g), conversão alimentar por massa de ovos (kg/kg), conversão alimentar por dúzia de ovos (kg/dz) e viabilidade (%); para qualidade dos ovos foram avaliados: espessura de casca (mm), porcentagem de albúmen, porcentagem de gema e peso médio dos ovos (g). O horário de arraçoamento influenciou o desempenho e a qualidade de ovos de codorna.O horário de 16 horas apresentou melhores resultados em todos os ciclos testados, exceto os ciclos que apresentaram maior temperatura, quando a qualidade dos ovos produzidos e o desempenho foram favorecidos peloarraçoamento realizado às 6 horas da manhã. Dessa forma recomenda-se o arraçoamento às 16 horas para codornas que não estejam submetidas às condições de estresse calórico.

Assuntos

RESUMO

In order to evaluate the performance and egg quality of quails on different time feeding, One hundred ninety two Japanese quail (Coturnix coturnix japonica) at 24 weeks of age were distributed in a completely randomized design with two replications and twelve treatments eight birds each. The treatments consisted of two different times of feeding at 6h and 16h. The performance was evaluated by the feed intake (g/bird/day), egg production (%), egg mass (g), feed conversion per egg mass (kg/kg ), feed conversion per dozen eggs (kg/dz) and viability (%). The egg quality was evaluated by the eggshell thickness (mm), percentage of albumen, yolk percentage and average egg weight (g). The feeding time at 16h favored the performance of Japanese quails at 26 and 34 wk of age considering egg production, egg mass and average egg weight. Thus, it is recommended to feed the quails at times that coincide with the highest egg laying intensity, which ranges from 16 to 19h.(AU)

Com o objetivo de avaliar o desempenho e a qualidade de ovos de codornas arraçoadas em diferentes horários na produção, foram utilizadas 192 codornas japonesas com 24 semanas de idade, distribuídas em um delineamento inteiramente casualizado com dois tratamentos e doze repetições de oito aves cada. Os tratamentos corresponderam a dois horários de arraçoamento: 6:00h e 16:00h. Para o desempenho foram avaliados: consumo de ração (g/ave/dia), produção de ovos (%), massa de ovos (g), conversão alimentar por massa de ovos (kg/kg), conversão alimentar por dúzia de ovos (kg/dz) e viabilidade (%); para qualidade dos ovos foram avaliados: espessura de casca (mm), porcentagem de albúmen, porcentagem de gema e peso médio dos ovos (g). O horário de arraçoamento influenciou o desempenho e a qualidade de ovos de codorna.O horário de 16 horas apresentou melhores resultados em todos os ciclos testados, exceto os ciclos que apresentaram maior temperatura, quando a qualidade dos ovos produzidos e o desempenho foram favorecidos peloarraçoamento realizado às 6 horas da manhã. Dessa forma recomenda-se o arraçoamento às 16 horas para codornas que não estejam submetidas às condições de estresse calórico.(AU)

Assuntos

RESUMO

Successful incubation affects the number of healthy chicks in all poultry species. This study examined the effect of eggshell thickness on the hatching rates of guinea fowl and pheasant eggs. In total, 964 guinea fowl and 1,728 pheasant eggs were used in the study. Eggshell thickness was measured directly with an ultrasound gauge. Thicknesses ranged between 0.27-0.47 mm in guinea fowl and 0.24-0.49 mm in pheasant eggs. Incubation periods were 28 days for guinea fowl and 25 days for pheasant eggs. At the end of the incubation period, unhatched eggs were broken to identify the causes of embryonic mortality. Eggs were classified as thin-, medium- and thick-shelled, and hatching rates were calculated as a function of eggshell thickness. Differences in hatching rates of guinea fowl and pheasant eggs with different shell thicknesses were not statistically significant (p>0.05).(AU)

Assuntos

RESUMO

Successful incubation affects the number of healthy chicks in all poultry species. This study examined the effect of eggshell thickness on the hatching rates of guinea fowl and pheasant eggs. In total, 964 guinea fowl and 1,728 pheasant eggs were used in the study. Eggshell thickness was measured directly with an ultrasound gauge. Thicknesses ranged between 0.27-0.47 mm in guinea fowl and 0.24-0.49 mm in pheasant eggs. Incubation periods were 28 days for guinea fowl and 25 days for pheasant eggs. At the end of the incubation period, unhatched eggs were broken to identify the causes of embryonic mortality. Eggs were classified as thin-, medium- and thick-shelled, and hatching rates were calculated as a function of eggshell thickness. Differences in hatching rates of guinea fowl and pheasant eggs with different shell thicknesses were not statistically significant (p>0.05).

Assuntos

RESUMO

Incubation is an important factor in poultry production, particularly in species with relatively low fertility and hatchability rates. This study examined the effect of eggshell thickness on hatching traits of partridges (A. chukar). A total of 462 eggs from intensively reared partridges were separated into three groups according to eggshell thickness, which was measured ultrasonically before incubation. Hatchability, chick weight, and chick length were assessed at the end of the incubation period. Hatching times were recorded during hatching. Embryonic mortalities in unhatched eggs were classified according to mortality stage at the end of incubation. The effect of eggshell thickness on hatchability was found to be insignificant for all groups. Moreover, eggshell thickness had no significant effect on chick weight or length.

Assuntos

RESUMO

Incubation is an important factor in poultry production, particularly in species with relatively low fertility and hatchability rates. This study examined the effect of eggshell thickness on hatching traits of partridges (A. chukar). A total of 462 eggs from intensively reared partridges were separated into three groups according to eggshell thickness, which was measured ultrasonically before incubation. Hatchability, chick weight, and chick length were assessed at the end of the incubation period. Hatching times were recorded during hatching. Embryonic mortalities in unhatched eggs were classified according to mortality stage at the end of incubation. The effect of eggshell thickness on hatchability was found to be insignificant for all groups. Moreover, eggshell thickness had no significant effect on chick weight or length.(AU)

Assuntos

RESUMO

The goal of the present study was to evaluate the influence of increasing levels of dietary calcium on performance, egg quality, and the amount of calcium retained in the meat and excreted by Japanese quails at the final production. Four hundred 46-58-week-old Japanese quails were distributed in a completely randomized design consisting of five calcium level treatments: T1 = 2.95%, T2 = 3.25%, T3 = 3.55%, T4 = 3.85% and T5 = 4.15% calcium. The performance variables included feed intake (g bird-1 day-1), egg production (%), feed conversion by egg mass and per dozen eggs, egg mass (g), and viability. For egg quality, we assessed egg weight, percentage of albumen, yolk weight, percentage of shell, and shell thickness. We also evaluated the amount of calcium present in the meat and the amount of calcium excreted by quails. Increasing levels of calcium linearly influenced feed conversion, weight of yolk, and percentage of eggshell. Shell thickness increased up to the 3.85% calcium treatment. Calcium content of the meat differed among the quails; the quails fed the lowest level of calcium (2.95%) showed higher calcium content in meat, whereas calcium excretion increased with increasing levels of calcium in the diet. In conclusion, the addition of 3.85% of calcium in quail feed at the end of production improved eggshell quality, and maintained internal quality and performance within t

O objetivo do presente estudo foi avaliar a influência de níveis crescentes de cálcio na dieta sobre o desempenho, a qualidade do ovo, e a quantidade de cálcio retido na carne e excretado por codornas japonesas em final da produção. Quatrocentas codornas japonesas de 46-58 semanas de idade foram distribuídas em um delineamento experimental inteiramente casualizado, sendo os tratamentos constituídos de cinco níveis de cálcio: T1 = 2,95%, T2 = 3,25%, T3 = 3,55%, T4 = 3,85% e T5 = 4,15%. As variáveis de desempenho incluíam o consumo de ração (g/ave/dia), produção de ovos (%), conversão alimentar por massa de ovo e por dúzia de ovos, massa de ovo (g), e viabilidade. Para a qualidade dos ovos foram avaliados o peso dos ovos, porcentagem de albúmen, peso da gema, porcentagem de casca e espessura da casca. Também foi avaliada a quantidade de cálcio presente na carne e a quantidade de cálcio excretado pelas codornas. O aumento dos níveis de cálcio influenciou linearmente a conversão alimentar, o peso de gema e a porcentagem de casca de ovo. A espessura da casca aumentou até o nível de inclusão de 3,85% de cálcio. O teor de cálcio da carne diferiu entre as codornas; as codornas alimentadas com o menor nível de cálcio (2,95%) apresentaram maior teor de cálcio na carne, enquanto a excreção de cálcio aumentou com o aumento dos níveis de cálcio na dieta. Em conclusão, a adição de 3,85% de c

RESUMO

The goal of the present study was to evaluate the influence of increasing levels of dietary calcium on performance, egg quality, and the amount of calcium retained in the meat and excreted by Japanese quails at the final production. Four hundred 46-58-week-old Japanese quails were distributed in a completely randomized design consisting of five calcium level treatments: T1 = 2.95%, T2 = 3.25%, T3 = 3.55%, T4 = 3.85% and T5 = 4.15% calcium. The performance variables included feed intake (g bird-1 day-1), egg production (%), feed conversion by egg mass and per dozen eggs, egg mass (g), and viability. For egg quality, we assessed egg weight, percentage of albumen, yolk weight, percentage of shell, and shell thickness. We also evaluated the amount of calcium present in the meat and the amount of calcium excreted by quails. Increasing levels of calcium linearly influenced feed conversion, weight of yolk, and percentage of eggshell. Shell thickness increased up to the 3.85% calcium treatment. Calcium content of the meat differed among the quails; the quails fed the lowest level of calcium (2.95%) showed higher calcium content in meat, whereas calcium excretion increased with increasing levels of calcium in the diet. In conclusion, the addition of 3.85% of calcium in quail feed at the end of production improved eggshell quality, and maintained internal quality and performance within t

O objetivo do presente estudo foi avaliar a influência de níveis crescentes de cálcio na dieta sobre o desempenho, a qualidade do ovo, e a quantidade de cálcio retido na carne e excretado por codornas japonesas em final da produção. Quatrocentas codornas japonesas de 46-58 semanas de idade foram distribuídas em um delineamento experimental inteiramente casualizado, sendo os tratamentos constituídos de cinco níveis de cálcio: T1 = 2,95%, T2 = 3,25%, T3 = 3,55%, T4 = 3,85% e T5 = 4,15%. As variáveis de desempenho incluíam o consumo de ração (g/ave/dia), produção de ovos (%), conversão alimentar por massa de ovo e por dúzia de ovos, massa de ovo (g), e viabilidade. Para a qualidade dos ovos foram avaliados o peso dos ovos, porcentagem de albúmen, peso da gema, porcentagem de casca e espessura da casca. Também foi avaliada a quantidade de cálcio presente na carne e a quantidade de cálcio excretado pelas codornas. O aumento dos níveis de cálcio influenciou linearmente a conversão alimentar, o peso de gema e a porcentagem de casca de ovo. A espessura da casca aumentou até o nível de inclusão de 3,85% de cálcio. O teor de cálcio da carne diferiu entre as codornas; as codornas alimentadas com o menor nível de cálcio (2,95%) apresentaram maior teor de cálcio na carne, enquanto a excreção de cálcio aumentou com o aumento dos níveis de cálcio na dieta. Em conclusão, a adição de 3,85% de c

RESUMO

Mycoplasma synoviae infection of hens has been associated with problems of eggshell quality called eggshell apex abnormalities (EAA). Little is known about the quality of EAA eggs from a commercial point of view, especially during their storage. The study aimed to examine the differences between EAA and normal eggs during storage under controlled conditions in 2 seasons, summer and winter, by comparing internal and external quality parameters. In a conventional egg production farm with white laying hens of varying ages in the city of Bastos, state of São Paulo, Brazil, 232 eggs were used in the summer season and 400 eggs in the winter season. Half of the eggs had EAA, and the other half were considered normal eggs for each season. The eggs were analyzed at 2, 7, 14, 21, and 28 d after being laid and stored from 24.6 to 25.8°C in summer and from 24 to 25°C in winter. There was no difference (P > 0.05) in the average egg weight between EAA and normal eggs at any studied time point, but in both seasons, the weight loss in EAA eggs was higher than in normal eggs. The losses in Haugh unit scores from the first to the last measurements were approximately 40% regardless of egg type or season of production. In comparing eggshell thickness, only the apices of the EAA eggs were thinner (P < 0.0001) than normal eggs in the summer, but in the winter, the EAA egg apices (P < 0.0001) and sides (P = 0.03) were both thinner. The presence of EAA did not affect the eggshell weight (P > 0.05) or eggshell percentage (P > 0.05). The eggshell strength of the EAA eggs was lower (P < 0.0001) than normal eggs in both the summer (16.57%) and winter (19.86%). The presence of EAA did not affect the internal quality of the egg, but was related to a greater loss of external quality and weight during storage.

Assuntos

RESUMO

This study aimed at studying alternative methods to induce molting and to compare them with the conventional forced-molting method (fasting). In the experiment, 420 70-week-old layers were used. The total experimental period was 140 days. Molting was induced during the first 28 days, when birds were submitted to the experimental treatments, and bird performance and egg quality parameters were determined during 112 subsequent days. A completely randomized experimental design was applied in a 5x2 factorial arrangement of five feed restriction regimes (0, 15, 30, 45, or 60g feed/bird/day) and with or without the addition of coarse-particle limestone to the feed, with seven replicates of six birds each. Egg quality was evaluated at the end of each 28-day period for three consecutive days, using three eggs per experimental unit (21 eggs/treatment), with a total of 210 eggs. It was concluded that feeding 15g feed/bird/day to induce molting is feasible, as birds submitted to this treatment presented similar performance and better egg quality than those submitted to fasting during molting. The use of coarse-particle limestone during molting did not influence post-molting bird performance or egg quality.

RESUMO

This study aimed at studying alternative methods to induce molting and to compare them with the conventional forced-molting method (fasting). In the experiment, 420 70-week-old layers were used. The total experimental period was 140 days. Molting was induced during the first 28 days, when birds were submitted to the experimental treatments, and bird performance and egg quality parameters were determined during 112 subsequent days. A completely randomized experimental design was applied in a 5x2 factorial arrangement of five feed restriction regimes (0, 15, 30, 45, or 60g feed/bird/day) and with or without the addition of coarse-particle limestone to the feed, with seven replicates of six birds each. Egg quality was evaluated at the end of each 28-day period for three consecutive days, using three eggs per experimental unit (21 eggs/treatment), with a total of 210 eggs. It was concluded that feeding 15g feed/bird/day to induce molting is feasible, as birds submitted to this treatment presented similar performance and better egg quality than those submitted to fasting during molting. The use of coarse-particle limestone during molting did not influence post-molting bird performance or egg quality.