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)

Assessing Differences in the Quality Properties and Ultrastructure of Eggshell as Affected by Chicken Strain and Flock Age During Incubation Period

Three hundred hatching eggs from two layer breeder flocks (Hy-Line Brown and hy-Line W-36; 150 each) were obtained at three different periods of laying cycle (early, middle and late stages). The hatching eggs were randomly taken to assess the impact of chicken strain, age, and hatching time on some eggshell measurements and structures. Results indicate that egg weight, shell percentage and shell thickness were significantly affected by strain, breeder age, and incubation time. Increasing rate of calcium absorption and utilization by the embryos during the embryonic stage clearly reflects the decrease occurred in eggshell strength. The differences of eggshell breaking strength during incubation time periods were 0.41 and 0.55 kg/cm2, the differences due to the incubation time may be due to the higher demand for calcium utilization in the late incubation period (18 days), observed on the10th day of incubation. Brown eggs recorded significant higher calcium percentage in eggshell compared to the white ones. The brown breeder hens recorded significant higher total pores per egg compared to the white egg. Concerning eggshell ultrastructure, total thickness of the brown eggshell was significantly higher than those of the white eggshell by about 3.7%. All parameters, except for total thickness, were significantly affected by the interaction between strain and breeder age. Finally, we conclude that some traits including egg weight, shell percentage, shell thickness, calcium percentages in eggshell, and total pores per egg were significantly affected by strain, breeder age, and incubation time. Eggshell ultrastructure of brown egg was better compared to the white ones.(AU)

Effect of different lighting sources on the performance of broiler breeder hens

The present study aimed to evaluate the effects of using light-emitting diode (LED) lamps versus incandescent/tungsten (Inc) bulbs on broiler breeder hens' productive performance during the brooding and rearing periods (25 weeks), as well as the first 15 weeks of production. A total of 46600 one-day-old Arbor Acres Plus breeder chicks were placed in eight enclosed houses and randomly/evenly divided into two groups (four houses for each group): birds raised under yellow LED lighting, and birds raised under orange Inc lighting. Several traits have been studied to determine productive performance, including body weight at different ages, body weight gain, feed consumption, feed conversion ratio, mortality rate, uniformity, age and weight at sexual maturity, egg number, egg production rate, egg number per bird, egg weight, and egg mass. According to the findings, using LED lighting instead of Inc lighting during the rearing period resulted in a significant improvement in all studied traits, and this positive effect continued until the production period, yielding excellent results for all studied production traits. LED lighting proved to be an effective source of lighting in broiler breeders' houses.(AU)

Effects of broiler breeder age on immune system development of progeny

The objective of this study was to determine the effects that breeder age has on digestive and immune system development; the transfer of immunoglobulins to egg yolk, yolk sac, and neonate chicks; and the immune response of chicks up to 35 days old. Three ages (32, 42, and 52 weeks) of Hubbard breeders were studied with ages as treatments. A total of 425 eggs were weighed for each of the three treatments and incubated. After hatching, a total of 300 1-day-old chicks were used in each treatment. We studied the development of the gastrointestinal tract and immune system of progeny and IgY transfer from breeder to progeny. Chicks from 52-week-old breeders had greater gastrointestinal tract growth up to seven days of life and greater body weight at 14 days. Older breeders (52 weeks) had higher amounts of IgY in serum and egg yolk. Chicks from the youngest breeders (32-weeks-old) had a better immune response at two weeks post-vaccination. It can be concluded that the older breeders have a greater capacity to immunize progeny up to 14 days. Strategies can be developed to increase IgY in the serum of young breeders and, consequently, increase the innate immunity of the newly-hatched chicks.(AU)

Effects of breeder age and short-term temperature stimulation during incubation on performance, organ weight, and carcass yield in male and female broilers / Efeitos da idade da matriz e de alterações curtas de temperatura de incubação no desempenho, peso dos órgãos e rendimento de carcaça em frangos de corte machos e fêmeas

Birds develop thermoregulatory control during the last days of incubation. Different temperature conditioning programs have been proposed to prepare broiler chicks for post-hatch life. This study aimed to investigate the effects of short-term temperature (STT) stimulation and breeder age on hatching performance, embryo development, yolk absorption, and post-hatch performance of male and female broilers. A 2 × 2 factorial completely randomized design was used, with two breeder ages (30 and 60 wk), two temperature incubation programs (control and STT), and 2,520 eggs per treatment. Eggs were distributed in two large-scale commercial incubators with a capacity of 120,960 eggs. The control group was subjected to a standard single-stage incubation program (37.2-37.4 °C), whereas the STT group was subjected to a temperature increment of 1 °C for 4 h on embryonic days 16, 17, 18, and 19. Embryos were analyzed at 16 and 19 days of incubation, and chicks at hatch. At 19 days of incubation, STT conditioning resulted in lower yolk sac weight in embryos from 60-wk-old breeders and higher relative weight of the gastrointestinal tract in embryos from 30-wk-old breeders. At hatch, males had lower residual yolk weight, females had greater length, and chicks from 60-wk-old breeders subjected to STT had higher body weight and relative weight of the gastrointestinal tract. Eggs from 30-wk-old breeders showed higher fertility and hatchability and lower infertility, mortality, and second-grade chick percentages. Regarding performance, it was found that males had higher body weight from 7 to 42 days of age and higher whole leg yields. Females, on the other hand, had higher fat yields. Breeder age and sex influenced gastrointestinal tract development, carcass yield, and performance. A 1 °C increase in incubation temperature for 4 h from days 16 to 19 of incubation affected yolk absorption and digestive tract development in chicks from 60-wk-old breeders without, however, influencing performance results.(AU)

As aves desenvolvem o controle do sistema termorregulatório durante os últimos dias de incubação, dessa forma, diferentes programas temperatura de incubação têm sido descritos para preparar os pintos de corte para a vida pós-eclosão. Objetivou-se nesse estudo, estabelecer os efeitos de alterações curtas na temperatura de incubação e da idade da matriz no desempenho de eclosão, desenvolvimento embrionário, absorção da gema e desempenho pós-eclosão de frangos de corte machos e fêmeas. O delineamento experimental foi inteiramente casualizado em fatorial 2 x 2 com 2 idades de matriz (30 e 60 semanas) e 2 programas de incubação de temperatura, controle (CT) e grupo de treinamento de temperatura de curto prazo (STT) e 2.520 ovos em cada tratamento. Os ovos foram distribuídos em 2 incubadoras comerciais de grande escala com capacidade para 120.960 ovos. O grupo CT seguiu um programa de incubação de estágio único padrão (37,2-37,4°C) e o STT teve um incremento em + 1 ° C por 4 hs nos dias 16, 17, 18 e 19 de incubação. Os embriões foram analisados aos 16 e 19 dias e pintinhos na eclosão. Aos 19 dias de incubação, embriões de matrizes com 60 semanas apresentaram menor peso do saco vitelino e embriões de matrizes com 30 semanas apresentaram maior porcentagem de trato gastrointestinal quando em STT. Na eclosão, os machos apresentaram menor vitelo residual, e as fêmeas apresentaram maior comprimento, pintinhos mais pesados e maior trato gastrointestinal quando originárias de matrizes de 60 semanas de idade e expostos ao STT. Na eclosão, os ovos com 30 semanas de idade apresentaram maior porcentagem de fertilidade e eclodibilidade e menor infertilidade, mortalidade e pintos de secunda categoria. No desempenho, os machos apresentaram maior peso corporal do 7° ao 42° dia e maiores valores de porcentagem de pernas e as fêmeas maiores valores de porcentagem de gordura. A idade das matrizes e o sexo influenciaram o desenvolvimento visceral, o rendimento de carcaça e o desempenho dos frangos de corte. O aumento de 1°C durante 4 horas entre os dias 16 e 19 de incubação afetou a absorção da gema e o trato digestivo em pintos de matrizes com 60 semanas de idade, sem refletir nos resultados de desempenho.(AU)

Performance and immune response of broilers born to breeders of different ages and fed different valine levels

Two experiments were carried out to evaluate the effects of digestible valine supplementation in pre-starter and starter diets on the productivity, nutrient metabolizability coefficient (NMC), and immune response of broilers from breeders of different ages. Experiments I and II were conducted with broilers in the pre-starter (1 to 7 days of age) and starter (8 to 21 days of age) phases, respectively. Broilers were fed diets that differed in their digestible valine content. In each trial, 400 male Cobb 500® chicks were randomly housed in a 2 × 4 factorial arrangement with eight treatments and five replicates of 10 birds each. The main effects were breeder age (37 vs. 52 weeks) and the digestible valine level in pre-starter (9.2, 10.2, 11.2, and 12.2 g/kg) and starter (8.3, 9.3, 10.3, and 11.3 g/kg) diets. Productive performance, intestinal histology, and immune response of broilers were evaluated. Supplementation with 11.2 g/kg valine in pre-starter diets improved NMC and increased villus height and villus:crypt ratio in the duodenum, jejunum development, and lymphocyte proliferation in the spleen of broilers at seven days of age, without improving performance (body weight gain, feed intake, and feed conversion ratio). In the starter phase, valine supplementation reduced feed intake but did not affect NMC, intestinal development, or immune response. The present results suggest that the same level of digestible valine should be used in the diet of broilers born to breeders of different ages, and the use of 9.2 and 8.3 g/kg digestible valine in pre-starter and starter diets, respectively, is sufficient to ensure satisfactory broiler performance. However, to improve the duodenum and jejunum development and immune response of broilers in the pre-starter phase, higher digestible valine levels are required.

Comparison of Mycoplasma gallisepticum Infection in Different Samples and Ages of Chicken Breeder Flocks

This study aimed to compare method-based and newly developed sample-based methods for Mycoplasma gallisepticum (MG) detection in different samples of breeder flocks suffering from respiratory disease problems by using culture, real-time PCR (rPCR) and ELISA from chicks and embryonated eggs. Overall, 450 samples of 19-day-old chicken embryos trachea, 450 samples of 8-day-old chicken tracheal swabs and 900 blood samples of 20-, 27-, 34-, 40- and 46-week-old breeder chickens from 5 flocks were sampled for 26 weeks, and were all tested for MG by culture, MG-rPCR and MG-ELISA. Culturing assays and rPCR were applied to 450 mixture samples from 19-day-old chicken embryos trachea and 450 tracheal swab samples (each pooled into groups of 3) from 8-day-old chicks from the same flocks. Also, 900 blood samples from the same 5 breeder flocks suffering from respiratory disease problems were tested by MG-ELISA. In individual sample-based analyses, 55 (18.3%) of the 300 pooled swab samples were positive for MG using culture methods, and 106 (35.3%) of the same samples were found positive by rPCR (sensitivity, specificity). The ELISAs indicated that 252 (28%) of the 900 breeding blood samples were MG seropositive. Using age-based analyses, the most positive period was 46 weeks, followed by 40 weeks, 34 weeks, 27 weeks and at least 20 weeks, in order of decreasing seropositivity. When comparing the culture and rPCR results of the two different sampling methods, chicken embryos trachea yielded more positive results than did tracheal swabs from the same flocks. In conclusion, rPCR is a highly specific, sensitive and reliable method for MG identification.(AU)

Comparison of Mycoplasma gallisepticum Infection in Different Samples and Ages of Chicken Breeder Flocks

This study aimed to compare method-based and newly developed sample-based methods for Mycoplasma gallisepticum (MG) detection in different samples of breeder flocks suffering from respiratory disease problems by using culture, real-time PCR (rPCR) and ELISA from chicks and embryonated eggs. Overall, 450 samples of 19-day-old chicken embryos trachea, 450 samples of 8-day-old chicken tracheal swabs and 900 blood samples of 20-, 27-, 34-, 40- and 46-week-old breeder chickens from 5 flocks were sampled for 26 weeks, and were all tested for MG by culture, MG-rPCR and MG-ELISA. Culturing assays and rPCR were applied to 450 mixture samples from 19-day-old chicken embryos trachea and 450 tracheal swab samples (each pooled into groups of 3) from 8-day-old chicks from the same flocks. Also, 900 blood samples from the same 5 breeder flocks suffering from respiratory disease problems were tested by MG-ELISA. In individual sample-based analyses, 55 (18.3%) of the 300 pooled swab samples were positive for MG using culture methods, and 106 (35.3%) of the same samples were found positive by rPCR (sensitivity, specificity). The ELISAs indicated that 252 (28%) of the 900 breeding blood samples were MG seropositive. Using age-based analyses, the most positive period was 46 weeks, followed by 40 weeks, 34 weeks, 27 weeks and at least 20 weeks, in order of decreasing seropositivity. When comparing the culture and rPCR results of the two different sampling methods, chicken embryos trachea yielded more positive results than did tracheal swabs from the same flocks. In conclusion, rPCR is a highly specific, sensitive and reliable method for MG identification.

Effects of Phytase Inclusion in Broiler Breeder Diets During Early Lay on their Fecal and Egg Characteristics

This study investigated the effects of phytase inclusion in broiler breeder diets on fecal and egg characteristics. A total of 48 female broiler breeders were evaluated in this study from 21 to 31 weeks of age. The dietary treatments were fed from 30 to 31 wks of age, and included a Positive Control (PosCon) diet, containing 3.0% calcium and 0.50% available phosphorus (AvP); a Negative Control (NegCon) diet, with 3.0% calcium and 0.25% AvP; Negative Control diet + 275 FTU/kg phytase (NegCon+275), and Negative control diet + 550 FTU/kg phytase (NegCon+550). Egg, yolk, albumin, and eggshell weight, albumin height, and eggshell thickness were measured. Fecal parameters included fecal moisture, liquid portion, and mineral content. After 14 d on the experimental diets during the onset of lay, the NegCon+550 diet increased (p 0.01) fecal moisture content. In general, hens fed the highest enzyme level (NegCon+550) excreted fewer (p 0.05) divalent and trivalent cations, which included Al, Fe, Mg, Mn, and Zn. Fecal Na and K levels were not affected by dietary treatments. The NegCon+550 diet increased fecal P when compared with the NegCon and the NegCon+275 diets. The NegCon+550 and PosCon diets exhibited similar fecal P. No significant effects on egg characteristics were observed. It was concluded that during early lay, various signs of fecal changes would probably be observed at phytase dosages above approximately 500 FTU/kg characterized by increased fecal moisture content and excretion of P in broiler breeders.(AU)

Effects of Phytase Inclusion in Broiler Breeder Diets During Early Lay on their Fecal and Egg Characteristics

This study investigated the effects of phytase inclusion in broiler breeder diets on fecal and egg characteristics. A total of 48 female broiler breeders were evaluated in this study from 21 to 31 weeks of age. The dietary treatments were fed from 30 to 31 wks of age, and included a Positive Control (PosCon) diet, containing 3.0% calcium and 0.50% available phosphorus (AvP); a Negative Control (NegCon) diet, with 3.0% calcium and 0.25% AvP; Negative Control diet + 275 FTU/kg phytase (NegCon+275), and Negative control diet + 550 FTU/kg phytase (NegCon+550). Egg, yolk, albumin, and eggshell weight, albumin height, and eggshell thickness were measured. Fecal parameters included fecal moisture, liquid portion, and mineral content. After 14 d on the experimental diets during the onset of lay, the NegCon+550 diet increased (p 0.01) fecal moisture content. In general, hens fed the highest enzyme level (NegCon+550) excreted fewer (p 0.05) divalent and trivalent cations, which included Al, Fe, Mg, Mn, and Zn. Fecal Na and K levels were not affected by dietary treatments. The NegCon+550 diet increased fecal P when compared with the NegCon and the NegCon+275 diets. The NegCon+550 and PosCon diets exhibited similar fecal P. No significant effects on egg characteristics were observed. It was concluded that during early lay, various signs of fecal changes would probably be observed at phytase dosages above approximately 500 FTU/kg characterized by increased fecal moisture content and excretion of P in broiler breeders.

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.

Effects of Dietary Supplementation of Soy Isoflavones on the Performance and Egg Quality in Native Chinese Breeder Hens

To investigate the effects of soy isoflavones (ISF) on the laying performance of Xueshan breeder hens at different phases of the egg production cycle, 32 weeks (wks) old local Chinese breeder hens were assigned to two groups with three replicates (750 hens/replicate) for control and treatment groups. Then every group was divided into three sub-groups following 4, 12, and 20 wks administration of control or ISF diet. General Linear Model procedure was used (2× 3), and treatments were considered of two factors (diets and time) with different levels (control and ISF diets; 4, 12, and 20 wks of diet supply time). Basal diet with 3 mg/kg ISF was used. Performance, egg quality, organs relative weight and cholesterol level were measured at three time-points of 36, 44, and 52-wks of age old. The results showed that both diets and time significantly affected the production performance and physiological parameters. In details, ISF inclusion significantly (p=0.02) decreased average egg weight and average feed intake compared to control at 52-wks of age old, however, feed conversation ratio was not affected by ISF diet. Moreover, ISF diet caused to an increase hatching rate (p=0.01) at 36-wks old hens, an abnormal egg rate decrease (p=0.02) at 44-wks old, an increase in yolk color (p=0.035) and Haugh unit (p=0.039), and a decrease in low-density lipoprotein cholesterol level (p=0.03) at 52-wks of age old. ISF diet also increased spleen relative weight (p=0.041) and total antioxidant capacity compared to the control group. The results revealed that ISF inclusion exerted some benefits, thus it could be a potential feed additive for the breeder hens.(AU)

Effects of Dietary Supplementation of Soy Isoflavones on the Performance and Egg Quality in Native Chinese Breeder Hens

To investigate the effects of soy isoflavones (ISF) on the laying performance of Xueshan breeder hens at different phases of the egg production cycle, 32 weeks (wks) old local Chinese breeder hens were assigned to two groups with three replicates (750 hens/replicate) for control and treatment groups. Then every group was divided into three sub-groups following 4, 12, and 20 wks administration of control or ISF diet. General Linear Model procedure was used (2× 3), and treatments were considered of two factors (diets and time) with different levels (control and ISF diets; 4, 12, and 20 wks of diet supply time). Basal diet with 3 mg/kg ISF was used. Performance, egg quality, organs relative weight and cholesterol level were measured at three time-points of 36, 44, and 52-wks of age old. The results showed that both diets and time significantly affected the production performance and physiological parameters. In details, ISF inclusion significantly (p=0.02) decreased average egg weight and average feed intake compared to control at 52-wks of age old, however, feed conversation ratio was not affected by ISF diet. Moreover, ISF diet caused to an increase hatching rate (p=0.01) at 36-wks old hens, an abnormal egg rate decrease (p=0.02) at 44-wks old, an increase in yolk color (p=0.035) and Haugh unit (p=0.039), and a decrease in low-density lipoprotein cholesterol level (p=0.03) at 52-wks of age old. ISF diet also increased spleen relative weight (p=0.041) and total antioxidant capacity compared to the control group. The results revealed that ISF inclusion exerted some benefits, thus it could be a potential feed additive for the breeder hens.

Is the eggshell quality influenced by the egg weight or the breeder age?

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)

Is the eggshell quality influenced by the egg weight or the breeder age?

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.

Embryonic mortality and broiler chick quality (Gallus gallus) from glass-shelled eggs / Mortalidade embrionária e qualidade do pinto ao nascer oriundo de ovo de casca vítrea de matriz pesada (Gallus gallus)

The glass-shelled egg has various points on the surface with light gray coloration, which becomes more visible with the passage of egg storage period. The objective of this work was to evaluate the stage of embryonic mortality, egg weight during the incubation period, hatch window, and quality of chicks at hatch from glass-shelled egg. The research was divided into two parts. In the first part, 80 eggs from 45 weeks old hens were incubated, being half normal eggs and half glass-shelled eggs, while in the second part, 80 eggs from 70 weeks old hens from the same flock as the previous one were incubated. Again, half were normal shelled and half were glass-shelled eggs. No differences were observed for embryonic mortality, egg weight, hatch quality (hatch weight, uniformity, and navel quality), and hatch window between normal and glass-shelled eggs from hens of 45 and 70 weeks of age. However, there was higher contamination in glass-shelled egg from 70-week-old breeder hens. The results show that the presence of glass-shelled egg does not seem to interfere with the quality of the chick at hatch in the breed, ages, and studied conditions, but causes higher contamination in glass-shelled egg from 70-week-old breeder hens.

Ovos de casca vítrea apresentam em suas superfícies pontos com coloração cinza claro de vários diâmetros, que ficam mais visíveis com o decorrer do período de armazenagem. Objetivou-se no trabalho, avaliar a fase de mortalidade embrionária, peso do ovo durante o período de incubação, intervalo de tempo de nascimento e a qualidade dos pintos ao nascerem oriundos de ovos de casca vítrea. A pesquisa foi dividida em duas partes. Na primeira parte, ocorreu a incubação de 80 ovos provenientes de matrizes com 45 semanas de idade sendo metade ovos normais e metade ovos vítreos e na segunda parte, foram incubados 80 ovos provenientes de matrizes com 70 semanas de idade do mesmo lote do anterior. Desses, metade eram normais e metade eram vítreos. Não houve diferença para mortalidade embrionária, peso do ovo, qualidade dos pintos ao nascerem (peso do pinto ao nascer, qualidade do umbigo e uniformidade) e intervalo de tempo de nascimento entre os ovos vítreos e normais oriundos de matrizes de 45 e 70 semanas de idade. Porém ovos de casca vítrea oriundos de matrizes de 70 semanas de idade apresentaram maior índice de contaminação.

Embryonic mortality and broiler chick quality (Gallus gallus) from glass-shelled eggs / Mortalidade embrionária e qualidade do pinto ao nascer oriundo de ovo de casca vítrea de matriz pesada (Gallus gallus)

The glass-shelled egg has various points on the surface with light gray coloration, which becomes more visible with the passage of egg storage period. The objective of this work was to evaluate the stage of embryonic mortality, egg weight during the incubation period, hatch window, and quality of chicks at hatch from glass-shelled egg. The research was divided into two parts. In the first part, 80 eggs from 45 weeks old hens were incubated, being half normal eggs and half glass-shelled eggs, while in the second part, 80 eggs from 70 weeks old hens from the same flock as the previous one were incubated. Again, half were normal shelled and half were glass-shelled eggs. No differences were observed for embryonic mortality, egg weight, hatch quality (hatch weight, uniformity, and navel quality), and hatch window between normal and glass-shelled eggs from hens of 45 and 70 weeks of age. However, there was higher contamination in glass-shelled egg from 70-week-old breeder hens. The results show that the presence of glass-shelled egg does not seem to interfere with the quality of the chick at hatch in the breed, ages, and studied conditions, but causes higher contamination in glass-shelled egg from 70-week-old breeder hens.(AU)

Ovos de casca vítrea apresentam em suas superfícies pontos com coloração cinza claro de vários diâmetros, que ficam mais visíveis com o decorrer do período de armazenagem. Objetivou-se no trabalho, avaliar a fase de mortalidade embrionária, peso do ovo durante o período de incubação, intervalo de tempo de nascimento e a qualidade dos pintos ao nascerem oriundos de ovos de casca vítrea. A pesquisa foi dividida em duas partes. Na primeira parte, ocorreu a incubação de 80 ovos provenientes de matrizes com 45 semanas de idade sendo metade ovos normais e metade ovos vítreos e na segunda parte, foram incubados 80 ovos provenientes de matrizes com 70 semanas de idade do mesmo lote do anterior. Desses, metade eram normais e metade eram vítreos. Não houve diferença para mortalidade embrionária, peso do ovo, qualidade dos pintos ao nascerem (peso do pinto ao nascer, qualidade do umbigo e uniformidade) e intervalo de tempo de nascimento entre os ovos vítreos e normais oriundos de matrizes de 45 e 70 semanas de idade. Porém ovos de casca vítrea oriundos de matrizes de 70 semanas de idade apresentaram maior índice de contaminação.(AU)

Effect of antioxidant supplementation in diets of roosters during the post-peak phase on reproduction and production characteristics of offspring / Efeito da suplementação de antioxidantes na dieta de reprodutores de frangos de corte na fase pós-pico sobre características reprodutivas e produtivas da progênie

This study aimed to evaluate the effects of antioxidant supplementation in diets of breeding roosters during the post-peak phase on reproduction characteristics and muscle performance of offspring in two similar breeder houses from a local company. Treatments consisted of a control diet and a diet supplemented with antioxidants (8 ppm canthaxanthin + 40 ppm lycopene + 150 ppm vitamin C). During the 66th week of age, eggs were incubated, and offspring were housed. Dietary supplementation of the blend of antioxidant resulted in higher (p0.05) of supplementation of the antioxidant blend on weight gain and breast weight and count and diameter of muscle fibers of offspring at 7 days of age. Feed conversion and weight gain from 14 to 35 days were better (p<0.05) in offspring from supplemented roosters. The supplementation of an antioxidant blend in roosters improved reproductive characteristics assessed and feed conversion and weight gain of offspring.

O objetivo foi avaliar o efeito da suplementação de antioxidantes em dietas para reprodutores machos de frangos de corte na fase pós-pico sobre características reprodutivas e muscular da progênie. O experimento foi conduzido no matrizeiro de uma agroindústria local. Os tratamentos consistiram em uma dieta controle e uma dieta suplementada com blend de antioxidantes (8 ppm de cantaxantina + 40 ppm de licopeno + 150 ppm de vitamina C). Na 66ª semana de idade, os ovos foram incubados e a progênie foi alojada. A suplementação de antioxidantes na dieta resultou em maior (p0,05) dos antioxidantes na dieta dos reprodutores sobre o ganho de peso e o peso de peito e a contagem e diâmetro da fibra muscular da progênie aos 7 dias de idade. A conversão alimentar e ganho de peso na fase de 14 a 35 dias foram melhores (p<0,05) para a progênie dos reprodutores suplementados. A suplementação de antioxidantes na dieta dos reprodutores melhorou as características reprodutivas avaliadas e o ganho de peso e a conversão alimentar da progênie.

Effect of antioxidant supplementation in diets of roosters during the post-peak phase on reproduction and production characteristics of offspring / Efeito da suplementação de antioxidantes na dieta de reprodutores de frangos de corte na fase pós-pico sobre características reprodutivas e produtivas da progênie

This study aimed to evaluate the effects of antioxidant supplementation in diets of breeding roosters during the post-peak phase on reproduction characteristics and muscle performance of offspring in two similar breeder houses from a local company. Treatments consisted of a control diet and a diet supplemented with antioxidants (8 ppm canthaxanthin + 40 ppm lycopene + 150 ppm vitamin C). During the 66th week of age, eggs were incubated, and offspring were housed. Dietary supplementation of the blend of antioxidant resulted in higher (p<0.05) weights of testicles, crests, dewlaps, dewlap thickness, and number of perforations (53.35 x 25.30) in relation to non-supplemented roosters. There was no significant effect (p>0.05) of supplementation of the antioxidant blend on weight gain and breast weight and count and diameter of muscle fibers of offspring at 7 days of age. Feed conversion and weight gain from 14 to 35 days were better (p<0.05) in offspring from supplemented roosters. The supplementation of an antioxidant blend in roosters improved reproductive characteristics assessed and feed conversion and weight gain of offspring.(AU)

O objetivo foi avaliar o efeito da suplementação de antioxidantes em dietas para reprodutores machos de frangos de corte na fase pós-pico sobre características reprodutivas e muscular da progênie. O experimento foi conduzido no matrizeiro de uma agroindústria local. Os tratamentos consistiram em uma dieta controle e uma dieta suplementada com blend de antioxidantes (8 ppm de cantaxantina + 40 ppm de licopeno + 150 ppm de vitamina C). Na 66ª semana de idade, os ovos foram incubados e a progênie foi alojada. A suplementação de antioxidantes na dieta resultou em maior (p<0,05) peso de testículos, cristas, peso e espessura de barbelas e maior número de perfurações (53,35 x 25,30) em relação aos não suplementados. Não houve efeito significativo (p>0,05) dos antioxidantes na dieta dos reprodutores sobre o ganho de peso e o peso de peito e a contagem e diâmetro da fibra muscular da progênie aos 7 dias de idade. A conversão alimentar e ganho de peso na fase de 14 a 35 dias foram melhores (p<0,05) para a progênie dos reprodutores suplementados. A suplementação de antioxidantes na dieta dos reprodutores melhorou as características reprodutivas avaliadas e o ganho de peso e a conversão alimentar da progênie.(AU)