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| Crosara,FSG; Pereira,VJ; Lellis,CG; Barra,KC; Santos,SKA; Souza,LCGM; Morais,TA; Litz,FH; Limão,VA; Braga,PFS; Fernandes,EA. |
| ABSTRACT 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... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Broiler breeders; Eggshell thickness; Shell area; Shell index. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2019000200314 |
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| Yamak,US; Boz,MA; Ucar,A; Sarica,M; Onder,H. |
| ABSTRACT 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... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Eggshell thickness; Ultrasound; Incubation; Guinea fowl; Pheasant. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2016000600049 |
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| Yamak,US; Sarica,M; Boz,MA; Ucar,A. |
| ABSTRACT 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.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Eggshell thickness; Partridge; Incubation; Ultrasound; Hatching time. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2016000500013 |
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| Molino,AB; Garcia,EA; Berto,DA; Pelícia,K; Silva,AP; Vercese,F. |
| 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... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Eggshell thickness; Feed restriction; Limestone; Welfare. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2009000200006 |
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