Arch.Geflügelk., 76 (4). S. 254 258, 2012, ISSN 0003-9098. Verlag Eugen Ulmer, Stuttgart Effects of layer age and different plumage colors on external and internal egg quality characteristics in Japanese quails (Coturnix coturnix japonica) Auswirkungen des Legehennenalters und unterschiedlicher Gefiederfarben auf Merkmale der äußeren und inneren Eiqualität bei der Japanischen Wachtel (Coturnix coturnix japonica) M. Sarı 1, Serpil Işık 1, K. Önk 2, M. Tilki 1 and T. Kırmızıbayrak 1 Manuscript received 16 June 2011, accepted 6 August 2011 Introduction Japanese quail is the smallest farmed avian species for commercial meat and egg productions employed as model material for research usually done in other poultry (PANDA and SINGH, 1990). It has marked advantages such as a laboratory animal, early sexual maturity, short generation interval, short incubation period, rapid growth and low feed consumption (BAUMGARTNER, 1994; SHOKOOHMAND et al., 2007). The eggs obtained from poultry, both in terms of reproduction and human nutrition has an important position. The internal and external quality characteristics of eggs for breeding companies are of great importance. Egg weight, shell weight, shell thickness, yolk weight and albumen weight are the important egg traits influencing egg quality and hatching performance if other management conditions and fertility are not the limiting factors (KHURSHID et al., 2003). Egg quality characteristics are influenced by many factors, including genetic and environmental ones (BEDNARCZYK, 1991). In addition, the qualities of eggs depend on the age and plumage colors of birds. The external and internal quality characteristics of the quail egg change significantly by age in several research studies (GONZALEZ, 1995; ALTINEL et al., 1996; NOWACZEWSKI et al., 2010). YANNAKOPOULOS and TSERVENI-GOUSSI (1986) reported that the egg weight and shell weight increased with age but that the shell thickness decreased in Japanese quails. It was also reported that yolk and albumen weight increased, whereas yolk and albumen index and Haugh unit decreased by age (SEKER et al., 2005). Research studies conducted on the external and internal quality characteristics of eggs obtained from quails with different plumage color lines and different age have not been encountered in literature. 1 Kafkas University, Veterinary Medicine Faculty, Department of Animal Breeding, Kars, Turkey 2 Kafkas University, Kars Vocational College, Department of Crop and Animal Production, Kars, Turkey However, one research study conducted on the external and internal quality characteristics of eggs obtained from quails with different plumage colors have been reported previously (YILMAZ et al., 2011). The present study was designed to determine the effects of layer age and different plumage colors on external and internal quality characteristics of the eggs in Japanese quails. Materials and Methods The data for this study were obtained from Japanese quail population at the quail breeding unit of Kafkas University, Kars, Turkey. A total of 320 quails was used and 1,241 eggs were analyzed in the present study. Totally, eggs from 256 female quails were collected in two sequential days of the related week. At the 12th, 15th, 18th and 21st week of layer age, 274, 358, 298 and 311 eggs were included in the study, respectively. The same procedure was applied to 356, 327, 166 and 392 eggs for quails with gray, brown, white and golden plumage color, respectively. Quail were used in the study belong to the same origin (Coturnix coturnix japonica). Four floors of egg laying cages were used in the five-floor cage and each floor consisted of 20 quails (16 female + 4 male). Quails were placed in the egg laying cages in a way that there would be 64 females of each color group in each floor. Quails were housed in colony cages with dimension of 45 110 25 cm (width length height). Quails were fed a concentrate (Table 1) to meet the National Research Council recommendations for laying quails (NRC, 1994). The quails were given quail diet containing 200 g CP/kg with 12.1 MJ/kg ME. Food and water were available ad libitum during the rearing period. A lighting program of 16 hours light/day was applied. During the study, digital display scale was used for weighing the eggs; a digital display caliper was used for measuring the width, length, yolk diameter, albumen length and width of the eggs; a table with a glass cover on it was used on which the eggs are broken; a 3-legged micrometer was used for measuring the heights of yolk and albumen, and a micrometer was used for measuring the shell thickness. Air-dried the shells were weighted together with the shell membrane. Shell thickness was measured at the sharp, blunt and equatorial parts, and the average shell thickness was obtained from the average values of these three parts.
Sari et al.: Egg quality characteristics in quails 255 Table 1. Ingredient and chemical analysis of the concentrate fed during the laying period Zusammensetzung und kalkulierte Nährstoffe der in der Legeperiode eingesetzten Futterration Ingredient % Corn 53.0 Soybean 36.0 Vegetable oil 3.25 Lime stone 6.00 Dicalciumphosphate 1.00 Dl-Methionine 0.10 Salt 0.30 Vit.-Min. Premix 1 0.35 Chemical analysis Dry matter 92.8 Crude protein 20.0 Metabolisable energy 2 (kcal/kg) 2900 Calcium (%) 3 Total Phosphorus (%) 0.60 Lysine (%) 0.80 Methionine (%) 0.46 1 Provided per kg concentrate: Vitamin A, 21 000 IU; Vitamin D 3, 4 200 IU; Vitamin E, 52.5 mg; Vitamin K 3, 4.38 mg; VitaminB 1, 5.25mg; Vita-min B 2, 12.25 mg; Vitamin B 6, 7 mg; Vitamin B 12, 0.03 mg; Folic acid, 1.75 mg; D-Biotin 0.08 mg; Vitamin C, 87.5 mg; Niacin,70 mg; Cal-D-Pantothenat, 14 mg; Choline chloride 218.75 mg; Fe, 140 mg; Zn, 105 mg; Cu, 14 mg; Co, 0.35 mg; I, 1.75 mg; Se, 0.26 mg; Mn, 140 mg. 2 Provided by calculation (NRC, 1994) These data were used to determine the external and internal quality characteristics of eggs with the following formulas (YANNAKOPOULOS and TSERVENI-GOUSI, 1986; NAZLIGUL et al., 2001) Shape index (%) = (Width (mm)/length (mm)) 100 Shell = (Shell weight (g)/egg weight (g)) 100 weight (g) = Egg weight (Shell weight + Yolk weight) Yolk = (Yolk weight (g)/egg weight (g)) 100 = ( weight (g)/egg weight (g)) 100 Yolk index (%) = (Yolk height (mm)/yolk diameter (mm)) 100 index (%) = ( height (mm)/{( length (mm) + width (mm))/2}) 100 Haugh unit = 100 log ( height (mm) + 7.57 1.7 Egg weight (g) 0.37 ) All data were analyzed with the SPSS statistical package (SPSS, 2003). General linear model procedure was used including effects of layer age and plumage color and their two way interaction. The significant means were compared by Duncan s test. Y ijk =μ+a i +b j +(a+b) ij +e ijk Where; Y ijk is the observation of measurement (egg weight, shape index, shell weight, shell ratio, shell thickness, yolk weight, albumen weight, yolk ratio, albumen ratio, yolk/albumen ratio, yolk index, albumen index and haugh unit). μ is the overall mean, a i is the effect of layer age (12, 15, 18, 21), b j is the effect of plumage color (gray, brown, white and golden), (a + b) ij is the interaction of plumage color with layer age, e ijk is the random error. Results The means of some external quality characteristics of eggs obtained from quail with layer age and different plumage color are presented in Table 2. It clearly shows that layer age and different plumage colors had significant effect on some external egg quality characteristics (P < 0.05, P < 0.001). The quail eggs obtained from the quails with gray plumage were found to be the heaviest. The lowest egg weights were obtained from the quails with white and golden plumage. The mean highest shape index was observed in the 15 th week of age in all lines and in quails with golden plumage. The highest value of shell ratio was obtained in the quails with white plumage and the lowest value was observed in the quails with gray plumage. In this research, as the quail age increased, egg weight, shell weight, yolk weight and albumen weight also increased. The quail eggs obtained from the quails with gray plumage were found to be heavier. The means of some internal quality characteristics of eggs obtained from quail with layer age and different plumage color are presented in Table 3. Internal quality characteristics were significantly depend on layer age and plumage colors (P < 0.01, P < 0.001). Generally, interaction between layer age and plumage color was statistically significant (P < 0.01, P < 0.001). Yolk and albumen index, and Haugh unit were higher and yolk and albumen weight were lower in eggs from young layer quails. The highest means for yolk and albumen weight, yolk ratio, and yolk/albumen ratio were found in the quails with gray plumage. While the brown, white and quails with gray plumages were found to be similar in terms of Haugh unit, the lowest value was observed in the quails with golden plumage. In this research, as the quail age increased, yolk index, albumen index and Haugh unit decreased. Discussion Both age of quail and plumage color can significantly influence egg quality traits. In this study, observed that increase of egg weight together with age of quail. The mean egg weight of quail in this study was about 1 g smaller than that reported by ORHAN et al. (2001) but similar to the results obtained by ALTINEL et al. (1996), SEKER et al. (2005) and SEZER (2007). The mean egg weights observed in this study was higher than those reported by GONZALEZ (1995), OZCELIK (2002) and DUDUSOLA (2010). The egg weight values obtained from the plumage color lines in the study were found to be lower than those given by YILMAZ and CAGLAYAN (2008), RABIE TARIK et al. (2009) and YILMAZ et al. (2011). The egg shape index was not depending on age of the quails. Similar results have been also reported by NOWAC- ZEWSKI et al. (2010). However, GONZALEZ (1995) reported a
256 Sari et al.: Egg quality characteristics in quails Table 2. Means of the some external quality characteristics of eggs obtained from quail with layer age and different plumage colors Mittelwerte einiger äußerer Qualitätsmerkmale der Wachteleier in Abhängigkeit vom Alter und der Gefiederfarbe der Hennen Characteristics Egg weight (g) Shape index (%) Shell weight (g) Shell ratio (%) Shell thickness (mm) Mean (n = 256) 11.5 ± 0.030 78.8 ± 0.001 1.24 ± 0.010 10.85 ± 0.080 0.200 ± 0.0030 Layer age *** NS *** NS * 12 week (n = 256) 11.2 ± 0.060d 78.8 ± 0.002 1.20 ± 0.010c 10.80 ± 0.090 0.200 ± 0.010ab 15 week (n = 256) 11.4 ± 0.050c 79.1 ± 0.002 1.23 ± 0.010b 10.80 ± 0.080 0.210 ± 0.010a 18 week (n = 256) 11.6 ± 0.050b 78.8 ± 0.002 1.26 ± 0.010a 10.90 ± 0.080 0.200 ± 0.010ab 21 week (n = 256) 11.7 ± 0.050a 78.6 ± 0.002 1.27 ± 0.010a 10.90 ± 0.080 0.190 ± 0.010b Color *** *** *** *** NS Brown (n = 64) 11.4 ± 0.050b 79.3 ± 0.002ab 1.20 ± 0.010c 10.53 ± 0.080c 0.190 ± 0.010 White (n = 64) 11.2 ± 0.050c 78.9 ± 0.002b 1.27 ± 0.010a 11.40 ± 0.080a 0.200 ± 0.010 Golden (n = 64) 11.2 ± 0.070c 79.7 ± 0.002a 1.24 ± 0.010b 11.17 ± 0.110b 0.200 ± 0.010 Gray (n = 64) 12.1 ± 0.050a 77.4 ± 0.002c 1.24 ± 0.010ab 10.30 ± 0.070c 0.210 ± 0.010 Layer age*color *** *** ** *** NS a, b, c: The differences among the values bearing different superscript on the same row line are significant (P < 0.05). NS: Non significant (P > 0.05), *: P < 0.05, **: P < 0.01, ***: P < 0.001 significant decrease of the egg shape index of quail by approximately 0.95 percentage points in the period between 12 and 21 weeks of age. Egg shape index depends on plumage colors of the quails. The mean shape index values obtained from the brown, white and gray plumage color in the study were similar to the values reported by YILMAZ and CAGLAYAN (2008) and YILMAZ et al. (2011). The shell weight values were found to be higher compared to the values obtained in most research studies (ALTAN et al., 1998; MIGNON-GRASTEAU and MINVIELLE, 2003; ALKAN et al., 2010). The overall mean values for shell thickness in our study agree with the values reported that by PUNYA KUMARI et al. (2008) and NOWACZEWSKI et al. (2010) for quail eggs. The shell thickness values obtained from the plumage color lines in the study were lower than the values reported by YILMAZ et al. (2011). There were significant differences among the layer age lines for yolk and albumen weight. The yolk weight in the present study were higher than those reported by some authors for quail (MIGNON-GRASTEAU and MINVIELLE, 2003; DUDUSOLA, 2010). The mean yolk and albumen weights observed were lower than those reported by COSTA et al. (2008), PUNYA KUMARI et al. (2008) and NOWACZEWSKI et al. (2010). The yolk weight values of the plumage color lines determined by YILMAZ et al. (2011) were found to be similar to the values obtained in the present study. In the same way there were significant differences among the plumage color lines for albumen weight. The yolk ratio in the present study were higher than those reported by some authors for quail (NAZLIGUL et al., 2001; SEZER, 2008), however, the observed values lower than that reported by OZCELIK (2002). The mean yolk ratio, albumen ratio and yolk/albumen ratio depend on plumage colors of the quails. The yolk and albumen ratio values of the brown and golden group determined by RABIE TARIK et al. (2009) were found to be lower to the values obtained in the present study. For yolk quality, it was found that the highest index occurred at the beginning of the laying period (12 nd week of age). However, the mean value for the entire reproductive period for the yolk index was 5.0 percentage points lower in comparison with those reported by GONZALEZ (1995) for quail in the period from week 12 to 21 of age. On the other hand, SEKER et al. (2005) demonstrated a higher value for the yolk index in quail eggs laid in the 15 th and 17 th weeks than in week 9 of age. Yolk index values obtained from the brown and quails with gray plumage in the study were similar to the values reported by YILMAZ et al. (2011), the mean value obtained from the quails with white plumages was found to be higher than YILMAZ et al. (2011). However, the mean values obtained from the brown and quails with golden plumages were found to be lower than brown and golden plumage determined by RABIE TARIK et al. (2009). The albumen index as well as Haugh unit was the highest at the beginning of the laying period. The mean results for the entire reproductive period regarding albumen index were 3.0 percentage points lower in comparison with those reported by NAZLIGUL et al. (2001) for quail (12 to 22 week of age). GONZALEZ (1995) reported higher values of albumen index and Haugh units at the beginning of the laying season. The mean albumen index values obtained from the plumage color lines in the study were found to be lower than YILMAZ et al. (2011). However, Haugh unit value in this study obtained from the plumage color lines was found to be higher than YILMAZ et al. (2011). The external and internal egg quality characteristics in quails are effected variety of factors such as genetics, differences in body weight, inbreeding, nutrition, health, age, maintenance, environmental conditions, egg storage conditions and egg storage duration. According to the results obtained in this research, as the quail age increased, egg weight, shell weight, yolk weight and albumen weight increased, while yolk index, albumen index and Haugh unit decreased. The Haugh units observed in quails with plumage brown, white, golden and gray were found to be higher compared to the other research. We hope that the results obtained in this study are expected to help further researchers on these traits as well as the breeders. Summary The aim of the study was to determine the effect layer age and different plumage colors on external and internal egg quality characteristics of Japanese quails (Coturnix coturnix
Sari et al.: Egg quality characteristics in quails 257 Table 3. Means of the some internal quality characteristics of eggs obtained from quail with different layer age and plumage colors Mittelwerte einiger innerer Qualitätsmerkmale der Wachteleier in Abhängigkeit vom Alter und der Gefiederfarbe der Hennen Haugh unit index Yolk index Yolk/albumen Yolk weight (g) Characteristics Yolk weight (g) Mean (n = 256) 3.75 ± 0.010 6.47 ± 0.020 32.8 ± 0.100 56.4 ± 0.110 58.7 ± 0.320 45.0 ± 0.130 6.36 ± 0.040 91.4 ± 0.090 Layer age *** *** NS NS NS *** ** *** 12 week (n = 256) 3.67 ± 0.030b 6.30 ± 0.050b 32.8 ± 0.210 56.4 ± 0.230 59.1 ± 0.650 46.0 ± 0.270a 6.54 ± 0.090a 92.8 ± 0.190a 15 week (n = 256) 3.75 ± 0.020b 6.43 ± 0.040b 32.9 ± 0.180 56.3 ± 0.200 59.1 ± 0.560 45.6 ± 0.230a 6.40 ± 0.070ab 91.5 ± 0.160b 18 week (n = 256) 3.77 ± 0.030b 6.54 ± 0.040a 32.6 ± 0.200 56.5 ± 0.220 58.2 ± 0.610 45.4 ± 0.260a 6.32 ± 0.080ab 91.1 ± 0.180b 21 week (n = 256) 3.82 ± 0.030a 6.61 ± 0.040a 32.7 ± 0.200 56.4 ± 0.220 58.5 ± 0.620 42.9 ± 0.260b 6.16 ± 0.080b 90.1 ± 0.180c Color *** *** *** *** *** *** *** *** Brown (n = 64) 3.72 ± 0.020b 6.50 ± 0.040b 32.6 ± 0.180b 56.9 ± 0.200a 57.8 ± 0.560bc 45.6 ± 0.230ab 6.22 ± 0.070b 91.9 ± 0.160a White (n = 64) 3.63 ± 0.030c 6.30 ± 0.040c 32.5 ± 0.190b 56.1 ± 0.210b 58.6 ± 0.580b 46.2 ± 0.240a 6.65 ± 0.080a 91.8 ± 0.170a Golden (n = 64) 3.55 ± 0.030d 6.38 ± 0.060bc 31.8 ± 0.260c 57.0 ± 0.290a 56.3 ± 0.820c 44.7 ± 0.340b 6.05 ± 0.110b 90.0 ± 0.240b Gray (n = 64) 4.11 ± 0.020a 6.71 ± 0.040a 34.1 ± 0.170a 55.6 ± 0.190b 62.3 ± 0.530a 43.6 ± 0.220c 6.50 ± 0.070a 91.9 ± 0.160a Layer age*color *** *** *** *** *** *** ** *** a, b, c: The differences among the values bearing different superscript on the same row line are significant (P < 0.05). NS: Non significant (P > 0.05), **: P < 0.01, ***: P < 0.001 japonica). A total of 1,241 quail eggs at quail age of 12, 15, 18 and 21 weeks were used in the study. The eggs were gathered from quails with plumages in gray (common quail plumage), brown, white and golden. Layer age affected external quality characteristics like egg weight, shell weight and shell thickness significant (P < 0.05, P < 0.001). The differences among the plumage color groups have been significant for egg weight, shape index, shell weight and ratio (P < 0.001). Layer age affected yolk weight, albumen weight, yolk index, albumen index and Haugh unit significantly (P < 0.01, P < 0.001). In the same way significant differences have been observed between plumage color groups for yolk weight, albumen weight, yolk ratio, albumen ratio, yolk/albumen ratio, yolk index, albumen index and Haugh unit (P < 0.001). Generally, interaction between layer age and plumage color was significant (P < 0.01, P < 0.001). According to the results obtained in this research, as the quail age increased, egg weight, shell weight, yolk weight and albumen weight increased, while yolk index, albumen index and Haugh unit decreased. The Haugh units observed in quails with plumage brown, white, golden and gray were found to be higher compared to other research in literature. Key words Quail, layer age, plumage color, egg quality. Zusammenfassung Auswirkungen des Legehennenalters und unterschiedlicher Gefiederfarben auf Merkmale der äußeren und inneren Eiqualität bei der Japanischen Wachtel (Coturnix coturnix japonica) Die Untersuchung hatte zum Ziel, den Einfluss von Alter und Gefiederfarbe Japanischer Wachtelhennen (Coturnix coturnix japonica) auf verschiedene Merkmale der äußeren und inneren Eiqualität zu bestimmen. Hierzu wurden insgesamt 1241 Eier von den Wachtelhennen im Alter von 12, 15, 18 und 21 Wochen gesammelt. Die Hennen hatten entweder graues (normales Wachtelgefieder), braunes, weißes oder goldenes Gefieder. Das Alter der Hennen hatte einen signifikanten Einfluss auf die äußeren Qualitätsmerkmale Eigewicht, Schalengewicht und Schalendicke (P < 0,05; P < 0,001). In ähnlicher Weise wurden signifikante Unterschiede zwischen den verschiedenen Gefiederfarben für das Eigewicht, den Formindex, das Schalengewicht und den Schalenanteil ermittelt (P < 0,001). Das Hennenalter beeinflusste signifikant das Dottergewicht, das Eiklargewicht, den Dotterindex, den Eiklarindex und die Haugh-Einheit (P < 0,01; P < 0,001). Es wurden ebenfalls signifikante Unterschiede zwischen den Gefiederfarben für das Dottergewicht, das Eiklargewicht, den Dotteranteil, den Eiklaranteil, das Dotter/Eiklar-Verhältnis, den Dotter-Index, den Eiklar-Index und die Haugh- Einheit ermittelt (P < 0,001). Generell waren die Interaktionen zwischen dem Hennenalter und der Gefiederfarbe signifikant (P < 0,01; P < 0,001). Die Ergebnisse der Untersuchung belegen, dass mit zunehmendem Alter der Wachtelhennen das Eigewicht, das Schalengewicht, das Dottergewicht und das Eiklargewicht zunehmen, während der Dotter-Index, der Eiklar-Index und die Haugh-Einheiten abnehmen. Die Haugh-Einheiten der Eier der Wachtelhennen mit braunem, weißem, goldenem und grauem Gefieder waren insgesamt höher als in der Literatur in anderen Untersuchungen angegeben.
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