Effect of the Line and Age of Female Broiler Breeder on Hatchability Performance of Eggs

An experiment was conducted to assess how hatchability performance of eggs is affected by line and age of female broiler breeders. Response variables analyzed were hatchability, infertility, pipping (i.e., pipped shell but not emerged), embryonic mortality (1st, 2nd, and 3rd wk), and embryonic malposition. The trials involved a total of 2,880 fertile eggs from two broiler breeder lines (Ross 308 and Cobb 500) at two different ages (30 and 50 wk). A 2 x 2 factorial design was used, where the broiler breeder line and broiler breeder age were the main effects. The hatchability in the Ross 308 line was higher than the Cobb 500 line, but its infertility was higher than the Ross 308 line. Hatchability in interaction (50 wk age of the hen in the Cobb 500 line) was less, and their infertility was higher. Embryonic mortality, pipping, and embryonic malposition did not present differences for the interaction between factors. The results suggest that hatchability performance of eggs can be improved, if egg management and incubation procedures are adjusted to account for the interaction between broiler breeder line and broiler breeder age.(AU)

Effects of breeder age on embryonic development, hatching results, chick quality, and growing performance of the slow-growing genotype.

The present study aimed to ascertain the effects of slow-growing breeder age on embryo development, incubation results, and chick quality and of the interaction between breeder age and hatching time on initial performance. A total of 630 hatching eggs obtained from a commercial flock of slow-growing broiler breeders (Isa Label Naked Neck) were evaluated in 2 experiments. The first experiment evaluated embryo development and hatching results for broiler breeder age treatments of 38 and 51 wk, whereas the second experiment evaluated broiler chick performance. For the second experiment, chicks were distributed in a 2 x 2 factorial randomized block (sex) experimental design consisting of 2 breeder ages (31 or 58 wk) and 2 hatching times (479-485 and 491-497 h). At 18 d of embryonic development, embryos of 51-wk-old breeders were larger than those of 38-wk-old breeders (P < 0.05), whereas yolk-free chick weight was similar (P > 0.05). Embryo organ weight was similar for the 2 breeder ages (P > 0.05); however, there was greater development of intestinal villi for embryos of the 51-wk-old breeders. There were no differences between breeder ages in hatchability and chick quality score (P > 0.05). Yolk-free chick weight at pulling was greater (P < 0.05) for chicks from 51-wk-old breeders. Hatching time did not affect performance from 1 to 7 d (P > 0.05); however, chicks hatching at 491-497 h had better performance from 1 to 28 d than did chicks hatching at 479-485 h (P < 0.05). In conclusion, the age of slow-growing breeders affects embryo villi development and chick weight but does not improve incubation results or chick quality. Chicks hatching later (491-497 h) had better performance results than chicks hatching earlier (479-485 h).

Effect of Breeder Age on the Progeny Performance of Three Naked-Neck Chicken Phenotypes

The study was planned to evaluate the effect of different naked-neck (NN) chicken genotypes and breeder ages on the growth performance of their progenies. A total of 126 chicks, from two breeder ages and three NN varieties, were reared up to 20 weeks of age. A randomized complete block design in factorial arrangement, with six treatments of seven replicates of two females and one male each, was applied. Treatments consisted of three NN varieties (light brown, black, and dark brown) and two breeder age groups (45 and 55 weeks old). Growth performance (body weight gain, feed intake and feed conversion ratio) were evaluated. Higher feed intake was observed in both the male and female progenies of 55-week-old compared with 45-week-old breeders. Light brown males had higher weight gain than dark brown males, whereas in the female progeny, higher weight gain was obtained in the black variety than that in the light brown and dark brown varieties. Regarding breeder age groups, both male and female progenies of 55-week-oldbreeders exhibited higher weight gain than those of 45-week-old breeders. The male progeny of 55-week-old black breeders showed the highest body weight gain among all treatments. Regarding female progeny, higher weight gain was observed in the black variety compared with the light brown and dark brown variety, and in the progeny of 55-week-old breeders than in the progeny of 45-week-old breeders. The interaction between factors showed that females from 55-week-old black breeder has the highest weight gain, whereas the lowest weight gain was found in the progeny of 45-week-old light brown breeders. The male progeny of light brown breeders showed better FCR than those of black and dark brown breeders and of 55-week-old breeders compared with that of 45-week-old breeders. The best FCR was obtained in the progeny of 55-week-old light brown breeders. In females, while no influence of breeder age was detected, better FCR was determined in black than in dark brown and light brown varieties; however, the interaction between factors was significant, with the best FCR obtained in the female progeny of 55-week-old black breeders, and worst in the progeny of 45-week-old light brown breeders. In conclusion, the light brown and black varieties of naked-neck chickens and the progeny of 55-week-old breeders presented better growth performance.(AU)

Effect of Breeder Age on the Progeny Performance of Three Naked-Neck Chicken Phenotypes

The study was planned to evaluate the effect of different naked-neck (NN) chicken genotypes and breeder ages on the growth performance of their progenies. A total of 126 chicks, from two breeder ages and three NN varieties, were reared up to 20 weeks of age. A randomized complete block design in factorial arrangement, with six treatments of seven replicates of two females and one male each, was applied. Treatments consisted of three NN varieties (light brown, black, and dark brown) and two breeder age groups (45 and 55 weeks old). Growth performance (body weight gain, feed intake and feed conversion ratio) were evaluated. Higher feed intake was observed in both the male and female progenies of 55-week-old compared with 45-week-old breeders. Light brown males had higher weight gain than dark brown males, whereas in the female progeny, higher weight gain was obtained in the black variety than that in the light brown and dark brown varieties. Regarding breeder age groups, both male and female progenies of 55-week-oldbreeders exhibited higher weight gain than those of 45-week-old breeders. The male progeny of 55-week-old black breeders showed the highest body weight gain among all treatments. Regarding female progeny, higher weight gain was observed in the black variety compared with the light brown and dark brown variety, and in the progeny of 55-week-old breeders than in the progeny of 45-week-old breeders. The interaction between factors showed that females from 55-week-old black breeder has the highest weight gain, whereas the lowest weight gain was found in the progeny of 45-week-old light brown breeders. The male progeny of light brown breeders showed better FCR than those of black and dark brown breeders and of 55-week-old breeders compared with that of 45-week-old breeders. The best FCR was obtained in the progeny of 55-week-old light brown breeders. In females, while no influence of breeder age was detected, better FCR was determined in black than in dark brown and light brown varieties; however, the interaction between factors was significant, with the best FCR obtained in the female progeny of 55-week-old black breeders, and worst in the progeny of 45-week-old light brown breeders. In conclusion, the light brown and black varieties of naked-neck chickens and the progeny of 55-week-old breeders presented better growth performance.

Impacts of breeder age, storage time and setter ventilation program on incubation and post-hatch performance of broilers

The impacts of breeder age (32 and 55 weeks), egg storage time (2-12 days), setter ventilation program (control-test) on incubation and post-hatch performance of broilers were investigated in this study. Young (Y) and old (O) breeders hatching eggs were incubated in two different setters operated by two different ventilation programs as control (C) and test (T). Incubation took place after a short (S) and long (L) time of storage in this study. According to the trial design, eight treatment groups were as YSC, YST, YLC, YLT, OSC, OST, OLC and OLT. In total 9600 eggs and 6400 chicks were used. Early stage embryonic mortality (ED) rates were lower and accordingly hatchability of fertile eggs (HF) were higher (p<0.05) in YS than the other treatment groups. In contrast, incubation performance in eggs hatched in C and T programs were found to be similar. However, interaction between treatments were significant (p<0.05) and ED and HF were significantly (p<0.05) improved at OC. Liveability in growing period was affected (p<0.05) by breeder age but it wasnt affected by storage time and incubation program. Higher post-hatch performance was achieved in chicks of OST but differences between groups werent significant except for chick weights in comparison by breeder age. However, interactions between treatments were significant (p<0.05) and reached the highest post-hatch performance in YST (p<0.05). In conclusion, the long time storage of old breeders eggs improved incubation and post-hatch performance when they were incubated at test program.(AU)

Impacts of breeder age, storage time and setter ventilation program on incubation and post-hatch performance of broilers

The impacts of breeder age (32 and 55 weeks), egg storage time (2-12 days), setter ventilation program (control-test) on incubation and post-hatch performance of broilers were investigated in this study. Young (Y) and old (O) breeders’ hatching eggs were incubated in two different setters operated by two different ventilation programs as control (C) and test (T). Incubation took place after a short (S) and long (L) time of storage in this study. According to the trial design, eight treatment groups were as YSC, YST, YLC, YLT, OSC, OST, OLC and OLT. In total 9600 eggs and 6400 chicks were used. Early stage embryonic mortality (ED) rates were lower and accordingly hatchability of fertile eggs (HF) were higher (p<0.05) in YS than the other treatment groups. In contrast, incubation performance in eggs hatched in C and T programs were found to be similar. However, interaction between treatments were significant (p<0.05) and ED and HF were significantly (p<0.05) improved at OC. Liveability in growing period was affected (p<0.05) by breeder age but it wasn’t affected by storage time and incubation program. Higher post-hatch performance was achieved in chicks of OST but differences between groups weren’t significant except for chick weights in comparison by breeder age. However, interactions between treatments were significant (p<0.05) and reached the highest post-hatch performance in YST (p<0.05). In conclusion, the long time storage of old breeders’ eggs improved incubation and post-hatch performance when they were incubated at test program.

Evaluation of incubation yield, vaccine response, and performance of broilers submitted to in-ovo vaccination at different embryonic ages

The aim of this study was to evaluate the effects of in-ovo vaccination on different incubation days of broiler embryos derived from young and old breeders on incubation indexes, vaccine response, and broiler performance. A number of 20,160 fertile eggs was distributed according to a completely randomized design in a 4 x 2 factorial arrangement (in-ovo vaccination on 16, 17, 18, or 19 days of incubation, and breeders of 31 or 52 weeks of age), totaling eight treatments with 15 replicates of 168 eggs each. Vaccination procedures and vaccines (strains and doses) were those routinely applied in commercial hatcheries. After hatch, 960 male chicks were housed and distributed according to the same experimental design previously applied in the hatchery. There were hatching losses (p < 0.05) when eggs were vaccinated before 18 days of incubation. Greater Marek's disease antibody titers were obtained when the in-ovo vaccination was performed on day 19 of incubation, regardless breeder age. Embryonic age at vaccination did not compromise broiler performance in the field, and the flexibility of embryonic age for in-ovo vaccination can reduces incubation costs.(AU)

Effect of broiler breeder age on the intestinal mucosa development of the embryos at 20 days of incubation

This study investigated the effect of broiler breeder age on the morphological development of the small intestine broiler embryos (villus height, crypt depth, microvillus height, and villus density) at 20 day of incubation. Eggs obtained from 30- and 60-wk-old broiler breeders were used. The results showed that embryos from older broiler breeders presented longer villi in the duodenum, jejunum, and ileum compared with younger broiler breeders. In addition, embryos from older broiler breeders presented deeper crypts in the jejunum and ileum, longer microvilli in jejunal enterocytes, and lower villus density (microvillus number/mm2) in the duodenum and ileum than younger breeders. These results suggest that breeder age influences the gut mucosa development of broiler embryos. Embryos from older broiler breeder showed greater development of the small intestine mucosa than those from younger broiler breeder.(AU)

Evaluation of incubation yield, vaccine response, and performance of broilers submitted to in-ovo vaccination at different embryonic ages

The aim of this study was to evaluate the effects of in-ovo vaccination on different incubation days of broiler embryos derived from young and old breeders on incubation indexes, vaccine response, and broiler performance. A number of 20,160 fertile eggs was distributed according to a completely randomized design in a 4 x 2 factorial arrangement (in-ovo vaccination on 16, 17, 18, or 19 days of incubation, and breeders of 31 or 52 weeks of age), totaling eight treatments with 15 replicates of 168 eggs each. Vaccination procedures and vaccines (strains and doses) were those routinely applied in commercial hatcheries. After hatch, 960 male chicks were housed and distributed according to the same experimental design previously applied in the hatchery. There were hatching losses (p < 0.05) when eggs were vaccinated before 18 days of incubation. Greater Marek's disease antibody titers were obtained when the in-ovo vaccination was performed on day 19 of incubation, regardless breeder age. Embryonic age at vaccination did not compromise broiler performance in the field, and the flexibility of embryonic age for in-ovo vaccination can reduces incubation costs.

Effect of broiler breeder age on the intestinal mucosa development of the embryos at 20 days of incubation

This study investigated the effect of broiler breeder age on the morphological development of the small intestine broiler embryos (villus height, crypt depth, microvillus height, and villus density) at 20 day of incubation. Eggs obtained from 30- and 60-wk-old broiler breeders were used. The results showed that embryos from older broiler breeders presented longer villi in the duodenum, jejunum, and ileum compared with younger broiler breeders. In addition, embryos from older broiler breeders presented deeper crypts in the jejunum and ileum, longer microvilli in jejunal enterocytes, and lower villus density (microvillus number/mm2) in the duodenum and ileum than younger breeders. These results suggest that breeder age influences the gut mucosa development of broiler embryos. Embryos from older broiler breeder showed greater development of the small intestine mucosa than those from younger broiler breeder.

Effect of Broiler Breeder Age and Glutamine Supplementation on the Development of the Intestinal Mucosa of 7-Day-Old Chicks

The aim of this study was to evaluate the possible effects of glutamine and broiler breeder age on the development of intestinal mucosa in broiler chicks during first week of age. For this purpose, 32 one-day-old broiler chicks were distributed according to a completely randomized experimental design in a 2 x 2 factorial arrangement. Treatments consisted of two broiler breeder ages (30 and 60 weeks) and two dietary glutamine supplementation levels (0% and 1%). The morphological development of intestinal mucosa, particularly villus height and crypt depth, was evaluated. The results showed that the supplementation with 1% of glutamine influenced the development of villus height in the duodenum (p=0.009), jejunum (p = 0.006), and ileum (p = 0.001), as well as crypt depth in the jejunum (p = 0.037) of 7-day-old broilers. These results suggest that the presence of glutamine influenced the development of intestinal mucosa during the first week of age, when these tissues are highly influenced by dietary components, especially by trophic agents. The results show that broiler breeder age (30 or 60 weeks) did not influence the evaluated parameters.

Effect of Broiler Breeder Age and Glutamine Supplementation on the Development of the Intestinal Mucosa of 7-Day-Old Chicks

The aim of this study was to evaluate the possible effects of glutamine and broiler breeder age on the development of intestinal mucosa in broiler chicks during first week of age. For this purpose, 32 one-day-old broiler chicks were distributed according to a completely randomized experimental design in a 2 x 2 factorial arrangement. Treatments consisted of two broiler breeder ages (30 and 60 weeks) and two dietary glutamine supplementation levels (0% and 1%). The morphological development of intestinal mucosa, particularly villus height and crypt depth, was evaluated. The results showed that the supplementation with 1% of glutamine influenced the development of villus height in the duodenum (p=0.009), jejunum (p = 0.006), and ileum (p = 0.001), as well as crypt depth in the jejunum (p = 0.037) of 7-day-old broilers. These results suggest that the presence of glutamine influenced the development of intestinal mucosa during the first week of age, when these tissues are highly influenced by dietary components, especially by trophic agents. The results show that broiler breeder age (30 or 60 weeks) did not influence the evaluated parameters.(AU)

Desempenho de codornas de corte oriundas de diferentes classes de idades da matriz e de peso dos ovos / Performance of European quails from different classes of breeder age and egg weight categories

Estudou-se o efeito interação idade da matriz versus peso do ovo sobre o desempenho produtivo de codornas de corte (Coturnix coturnix coturnix) no 21º e 42º dias de idade. Em cada classe de idade da matriz, iniciada a partir de 70, 205 e 280 dias, foram incubados 600 ovos, separados em três categorias de peso: categoria 1 − ovos com 11,0-12,9g; categoria 2 − ovos com 13,0-14,9g; e categoria 3 − ovos com 15,0-16,9g. Após a eclosão, em cada idade da matriz, foram utilizadas 225 codornas de um dia, de ambos os sexos, provenientes das três categorias de peso, sendo 75 codornas por categoria. O delineamento experimental foi inteiramente ao acaso, com os tratamentos consistindo de um fatorial 3x3, ou seja, três classes de idades da matriz x três categorias de peso do ovo, com cinco repetições de 15 codornas por unidade experimental. A dieta experimental foi única para todos os tratamentos com 28% de proteína bruta e 2900kcal de energia metabolizável. O desempenho das codornas foi avaliado por meio das variáveis ganho de peso (g), peso corporal (g), consumo da dieta (g/ave) e conversão alimentar (g de dieta/g de peso) no 21º e 42º dias de idade. Não houve interação significativa entre idade da matriz e categoria de peso do ovo sobre as características de desempenho das codornas. Codornas oriundas de ovos mais pesados e de matrizes das classes 205 e 280 dias de idade apresentaram maiores desempenhos. No 42º dia de idade das codornas, não houve diferença para categoria de peso do ovo. Ovos mais pesados originaram codornas mais pesadas ao nascimento.(AU)

The effects of breeder ages versus egg weight interaction on performance traits of European quail (Coturnix coturnix coturnix) at 21 and 42 days of age were studied in a completely randomized experimental design with 9 treatments, 5 replicates and 15 quails per experimental unit. The treatments consisted of a 3x3 factorial combination, three breeder ages (beginning at 70, 205 and 280 days of age) and three egg weight categories (category 1 - from 11.0 to 12.9g; category 2 - from 13.0 to 14.9g and category 3 - from 15.0 to 16.9g). The quails were fed a unique experimental diet containing 28% crude protein and 2900kcal of metabolizable energy. The following performance traits were recorded: body weight (g), weight gain (g), feed intake (g) and feed intake: weight gain ratio (g/g) at 21 and 42 days of age. No significant interaction effects between breeder age and egg weight categories were observed for all performance traits. Quails from heavier egg weight categories and breeder ages beginning at 205 and 280 days of age showed higher performance. No effects of egg weight categories on performance traits at 42 days of age were observed. Heavier egg weight categories resulted in a heavier quail at hatch.(AU)

Desempenho de codornas de corte oriundas de diferentes classes de idades da matriz e de peso dos ovos / Performance of European quails from different classes of breeder age and egg weight categories

Estudou-se o efeito interação idade da matriz versus peso do ovo sobre o desempenho produtivo de codornas de corte (Coturnix coturnix coturnix) no 21º e 42º dias de idade. Em cada classe de idade da matriz, iniciada a partir de 70, 205 e 280 dias, foram incubados 600 ovos, separados em três categorias de peso: categoria 1 − ovos com 11,0-12,9g; categoria 2 − ovos com 13,0-14,9g; e categoria 3 − ovos com 15,0-16,9g. Após a eclosão, em cada idade da matriz, foram utilizadas 225 codornas de um dia, de ambos os sexos, provenientes das três categorias de peso, sendo 75 codornas por categoria. O delineamento experimental foi inteiramente ao acaso, com os tratamentos consistindo de um fatorial 3x3, ou seja, três classes de idades da matriz x três categorias de peso do ovo, com cinco repetições de 15 codornas por unidade experimental. A dieta experimental foi única para todos os tratamentos com 28% de proteína bruta e 2900kcal de energia metabolizável. O desempenho das codornas foi avaliado por meio das variáveis ganho de peso (g), peso corporal (g), consumo da dieta (g/ave) e conversão alimentar (g de dieta/g de peso) no 21º e 42º dias de idade. Não houve interação significativa entre idade da matriz e categoria de peso do ovo sobre as características de desempenho das codornas. Codornas oriundas de ovos mais pesados e de matrizes das classes 205 e 280 dias de idade apresentaram maiores desempenhos. No 42º dia de idade das codornas, não houve diferença para categoria de peso do ovo. Ovos mais pesados originaram codornas mais pesadas ao nascimento.

The effects of breeder ages versus egg weight interaction on performance traits of European quail (Coturnix coturnix coturnix) at 21 and 42 days of age were studied in a completely randomized experimental design with 9 treatments, 5 replicates and 15 quails per experimental unit. The treatments consisted of a 3x3 factorial combination, three breeder ages (beginning at 70, 205 and 280 days of age) and three egg weight categories (category 1 - from 11.0 to 12.9g; category 2 - from 13.0 to 14.9g and category 3 - from 15.0 to 16.9g). The quails were fed a unique experimental diet containing 28% crude protein and 2900kcal of metabolizable energy. The following performance traits were recorded: body weight (g), weight gain (g), feed intake (g) and feed intake: weight gain ratio (g/g) at 21 and 42 days of age. No significant interaction effects between breeder age and egg weight categories were observed for all performance traits. Quails from heavier egg weight categories and breeder ages beginning at 205 and 280 days of age showed higher performance. No effects of egg weight categories on performance traits at 42 days of age were observed. Heavier egg weight categories resulted in a heavier quail at hatch.

Efeito da interação idade da matriz x peso do ovo sobre o desempenho de codornas de corte / Effect of female breeder age x egg weight interaction on the performance of meat type quails

Avaliou-se a interação idade da matriz versus peso do ovo sobre o desempenho produtivo de codornas de corte (Coturnix coturnix coturnix) no 21º e 42º dias de idade. Em cada classe de idade da matriz, iniciada a partir de 70, 205 e 280 dias, foram incubados 600 ovos, separados em três categorias de peso: categoria 1 - ovos com 11,0-12,9g; categoria 2 - ovos com 13,0-14,9g e categoria 3 - ovos com 15,0-16,9g. Após a eclosão, em cada idade da matriz, foram utilizadas 225 codornas de um dia, de ambos os sexos, provenientes das três categorias de peso, sendo 75 codornas por categoria. O delineamento experimental foi inteiramente ao acaso, e os tratamentos consistiram das três classes de idades da matriz x três categorias de peso do ovo, com cinco repetições de 15 codornas. A dieta experimental foi única para todos os tratamentos com 28 por cento proteína bruta e 2900kcal de energia metabolizável. A categoria peso do ovo e a classe de idade da matriz influenciaram o peso corporal, o ganho de peso e o consumo da dieta no 21º e 42º dias de idade. Codornas oriundas de ovos mais pesados e de matrizes das classes de 205 e 280 dias de idade apresentaram melhor desempenho (P<0,05). A viabilidade foi influenciada pela categoria peso do ovo, ou seja, codornas provenientes de ovos mais leves apresentaram menor viabilidade aos 21º e 42º dias de idade (P<0,05). Ovos mais pesados originaram codornas mais pesadas ao nascimento (P<0,05).(AU)

The effect of female breeder age x egg weight interaction was evaluated on the performance of meat type quails (Coturnix coturnix coturnix) at 21st and 42nd days of age. For every female breeder age class (70, 205, and 280 days of age), 600 eggs were classified according to egg weight class (class 1: 11.0-12.9; class 2: 13.0-14.9, and class 3: 15.0-16.9g). A total of 225 quails of both genders, totaling 75 quails for every egg weight class were used in this study. A completely randomized experimental design with five replicates of 15 quails was used. The experimental diets were formulated to contain 28 percent crude protein and 2,900 kcal of metabolizable energy (ME). Weight gain, body weight, feed consumption, and weight gain: feed consumption ratio from hatch to 21st day and from hatch to 42nd day of age were recorded. Both egg weight and female breeder age classes affected body weight, weight gain, and feed consumption at 21st and 42nd days of age. Quails from heavier egg weight class and female breeder age classes 205 and 280 days of age showed higher performance (P<0.05). Quail viability was affected by egg weight class, i.e. quails from lighter eggs showed lower viability at 21st and 42nd days of life. Heavier eggs originated heavier quails at hatch (P<0.05).(AU)

Efeito da interação idade da matriz x peso do ovo sobre o desempenho de codornas de corte / Effect of female breeder age x egg weight interaction on the performance of meat type quails

Avaliou-se a interação idade da matriz versus peso do ovo sobre o desempenho produtivo de codornas de corte (Coturnix coturnix coturnix) no 21º e 42º dias de idade. Em cada classe de idade da matriz, iniciada a partir de 70, 205 e 280 dias, foram incubados 600 ovos, separados em três categorias de peso: categoria 1 - ovos com 11,0-12,9g; categoria 2 - ovos com 13,0-14,9g e categoria 3 - ovos com 15,0-16,9g. Após a eclosão, em cada idade da matriz, foram utilizadas 225 codornas de um dia, de ambos os sexos, provenientes das três categorias de peso, sendo 75 codornas por categoria. O delineamento experimental foi inteiramente ao acaso, e os tratamentos consistiram das três classes de idades da matriz x três categorias de peso do ovo, com cinco repetições de 15 codornas. A dieta experimental foi única para todos os tratamentos com 28 por cento proteína bruta e 2900kcal de energia metabolizável. A categoria peso do ovo e a classe de idade da matriz influenciaram o peso corporal, o ganho de peso e o consumo da dieta no 21º e 42º dias de idade. Codornas oriundas de ovos mais pesados e de matrizes das classes de 205 e 280 dias de idade apresentaram melhor desempenho (P<0,05). A viabilidade foi influenciada pela categoria peso do ovo, ou seja, codornas provenientes de ovos mais leves apresentaram menor viabilidade aos 21º e 42º dias de idade (P<0,05). Ovos mais pesados originaram codornas mais pesadas ao nascimento (P<0,05).

The effect of female breeder age x egg weight interaction was evaluated on the performance of meat type quails (Coturnix coturnix coturnix) at 21st and 42nd days of age. For every female breeder age class (70, 205, and 280 days of age), 600 eggs were classified according to egg weight class (class 1: 11.0-12.9; class 2: 13.0-14.9, and class 3: 15.0-16.9g). A total of 225 quails of both genders, totaling 75 quails for every egg weight class were used in this study. A completely randomized experimental design with five replicates of 15 quails was used. The experimental diets were formulated to contain 28 percent crude protein and 2,900 kcal of metabolizable energy (ME). Weight gain, body weight, feed consumption, and weight gain: feed consumption ratio from hatch to 21st day and from hatch to 42nd day of age were recorded. Both egg weight and female breeder age classes affected body weight, weight gain, and feed consumption at 21st and 42nd days of age. Quails from heavier egg weight class and female breeder age classes 205 and 280 days of age showed higher performance (P<0.05). Quail viability was affected by egg weight class, i.e. quails from lighter eggs showed lower viability at 21st and 42nd days of life. Heavier eggs originated heavier quails at hatch (P<0.05).

Hematological values and body, heart and liver weights of male and female broiler embryos of young and old breeder eggs

This study analyzed broiler breeder age (29 or 60 wk-old) effects on physical characteristics of eggs (initial mass, mass loss, volume, diameter, surface area and density) and of eggshells(weight, volume, thickness, conductance, and porosity ), as well as the influence of embryo sex on hematological parameters and body, liver and heart weights during incubation (at days 13, 15, 18 and 21). Physical parameter values were lower in 29-wk-old broiler breeder eggs than those of 60-wk-old breeders, except for relative eggshell weight, which was higher. In both male and female embryos, erythrocytic parameters and the body, liver, and heart weights increased during the incubation. The embryos and their organs were heavier when derived from 60-wk-old breeder eggs as compared to 29-wk-old breeder eggs. At hatching, hematocrit values were higher in males than in females. Thrombocytes were the most frequent leukocytes in the blood. Thrombocyte percentage decreased and lymphocyte percentage increased during the last days of incubation. The results showed maternal age influence only on body, heart and liver weights, focal sex-related influence the hematocrit at hatching, and temporal effect of incubation on body and organ weights, as well as on red blood cell count, hematocrit, hemoglobin, plasma glucose, and lymphocytes, which increased during the incubation period, while mean corpuscular volume and thrombocyte values decreased.

Hematological values and body, heart and liver weights of male and female broiler embryos of young and old breeder eggs

This study analyzed broiler breeder age (29 or 60 wk-old) effects on physical characteristics of eggs (initial mass, mass loss, volume, diameter, surface area and density) and of eggshells(weight, volume, thickness, conductance, and porosity ), as well as the influence of embryo sex on hematological parameters and body, liver and heart weights during incubation (at days 13, 15, 18 and 21). Physical parameter values were lower in 29-wk-old broiler breeder eggs than those of 60-wk-old breeders, except for relative eggshell weight, which was higher. In both male and female embryos, erythrocytic parameters and the body, liver, and heart weights increased during the incubation. The embryos and their organs were heavier when derived from 60-wk-old breeder eggs as compared to 29-wk-old breeder eggs. At hatching, hematocrit values were higher in males than in females. Thrombocytes were the most frequent leukocytes in the blood. Thrombocyte percentage decreased and lymphocyte percentage increased during the last days of incubation. The results showed maternal age influence only on body, heart and liver weights, focal sex-related influence the hematocrit at hatching, and temporal effect of incubation on body and organ weights, as well as on red blood cell count, hematocrit, hemoglobin, plasma glucose, and lymphocytes, which increased during the incubation period, while mean corpuscular volume and thrombocyte values decreased.

Efeito da idade da matriz sobre o desempenho e rendimento de carcaça de frangos de corte / Effect of broiler breeder age on performance and carcass yield of broiler chickens

Avaliou-se efeito da idade da matriz sobre as características de desempenho, rendimento de carcaça e partes de frangos de corte, criados até 49 dias de idade. Foram utilizados 3600 pintos de um dia, oriundos de ovos de matrizes da linhagem Ross 308, distribuídos segundo um delineamento experimental inteiramente ao acaso, em esquema fatorial 5I2, com cinco idades de matrizes (29, 41, 58, 68 e 98 semanas) e dois sexos, com quatro repetições de 90 aves cada. Aos 21, 28, 35, 42 e 49 dias de idade, cinco frangos por parcela foram amostrados e abatidos após jejum alimentar de oito horas, para avaliação do rendimento de carcaça e partes. A idade da matriz influenciou (P<0,05) o desempenho das aves na fase inicial de criação (1 a 21 dias); os frangos oriundos de matrizes com 29 semanas de idade apresentaram menor rendimento. A idade da matriz não afetou (P>0,05) o rendimento de carcaça nas idades avaliadas. Os frangos oriundos de matrizes com 29 semanas apresentaram melhor rendimento de peito que aqueles de matrizes com 58 semanas. O sexo influenciou (P<0,05) tanto o desempenho quanto o rendimento de carcaça e partes dos frangos de corte. (AU)

The effect of broiler breeder age on performance and carcass yield of chickens reared until 49 days of age was evaluated. Three thousand and six hundred day-old chicks, from Ross x Ross breeder flocks, were assigned to a completely randomized design, in a 5×2 factorial (five broiler breeder ages - 29, 41, 58, 68 and 98 weeks and two sexes) with four replicates of 90 birds each. At 21, 28, 35, 42 and 49 days of age, 5 birds per pen were randomly sampled and processed after a period of 8 hours of feed withdrawal to evaluate carcass and parts yield. Breeder age affected (P<.05) broiler performance during the starter period (1 to 21 days), with birds from breeders with 29 weeks of age showing smaller performance. Carcass and part yields were not affected (P>.05) by breeder age, but broilers from breeders aging 29 weeks showed larger breast yield than broilers originated from breeders with 58 weeks. No differences (P>.05) were observed for other breeder ages. Sex of the broiler chicken affected (P<.05) the performance and carcass yield and parts.(AU)

Hatching distribution of eggs varying in weight and breeder age

Broiler chicks from one incubator hatch within long periods of time, which leads to dehydration and reduction in yolk sac reserves of those chicks that have hatched earlier and potentially impairs early performance. The present research investigated the hatching distribution at intervals of incubation using eggs of different weights within one breeder age or eggs from widely different breeder ages. Eggs from breeders at 27 and 59 weeks of age (54 and 69 g) and from breeders at 40 weeks of age, which were graded as light (58 g) and heavy (73 g), were placed in a commercial incubator. There were a total of 1,184 eggs distributed in four treatments and eight replicates: eggs from 27-week-old breeders (27B), eggs from 59-week-old breeders (59B), light eggs from 40-week-old breeders (40BL) and heavy eggs from 40-week-old breeders (40BH). Replicates were comprised of 37 eggs that were placed in each incubator tray. The treatments were physically separated from each other using a plate. Eggs were transferred to a hatcher after 432 hours of incubation and the first chick hatched at 449 hours of incubation. Afterwards, the number of completely hatched chicks from each replicate was recorded at six-hour intervals until 503 hours of incubation, when the hatchings stopped. Hatched chicks were removed from the trays after each measurement. Data were submitted to an analysis of variance with repeated measures. There was a significant interaction between breeder age and incubation length. The hatching onset of eggs from the old breeders was later compared to young breeders. Hatchability (%incubated eggs) was lower for the old breeders; however, differences in hatchability as a percentage of the hatched eggs were not so evident. Complete hatchability occurred only at 503 hours of incubation; however, more than 90% eggs had hatched 18 hours earlier.