NOWACZEWSKI S., KONTECKA H., ROSIÑSKI A., KOBERLING S., KORONOWSKI P. 2010. Eggs quality of Japanese quail depending on layer age and storage time. Folia biol. (Kraków) 58: [201][202][203][204][205][206][207].The aim of the study was to analyse egg quality changes of Japanese quail during the reproductive season and after several days of storage. A significantly higher egg weight was recorded in week 9 than in week 25 and week 31 of age of birds. The egg specific gravity value of eggs also decreased with the age of quails. The smallest yolk weight and its percentage proportion in egg mass were observed in week 25. Eggs laid in weeks 9 and 25 were characterised by similar and lower (P#0.05) white weight in comparison to those examined on the last date. The highest white proportion in egg weight was recorded during the 25 JD week. The value of this trait was similar or smaller on the remaining dates. Similar and lower values of the white index and Haugh units, in comparison with the first date, were determined in eggs laid on weeks 25 and 31, whereas similar and greater eggshell thickness than in the 9 JD week of age was recorded on the last two dates of examination. Lower (P#0.05) egg weight was observed after 5 and 8 than after 0 (measured on the day of laying) days of storage. Likewise, smaller egg specific gravity was recorded after three consecutive periods of storage in comparison with the eggs examined on the day of laying. Eggs examined after 3, 5 and 8 days of storage, in comparison with those stored for 0 days, were characterised by lower yolk index. Significantly smaller weight and white index than after 0 days were determined in eggs stored, respectively, for 5 and 8 as well as for 3, 5 and 8 days. Similarly, smaller numbers of Haugh units were determined after 3 consecutive storage periods in comparison with the eggs examined on the day of laying. Eggs stored for 0 and 3 days were characterised by a greater eggshell weight than those examined after 5 and 8 days. The weight of Japanese quail eggs decreased significantly from day 5 onwards, whereas the egg specific gravity -from the 3 H@ day of storage. Yolk and white quality began to deteriorate already after 3 days of egg storage. It appears, therefore, that egg storage of Japanese quails before hatching lasting more than 3 days in the analysed conditions deteriorated the eggshell quality and internal egg traits.

Storage time and eggshell colour of pheasant eggs vs. the number of blastodermal cells and hatchability results. Folia biol. (Kraków) 57: 121-130. The aim of this study was to investigate the number of the embryo blastodermal cells and hatchability of pheasant from eggs of different eggshell colours depending on the length of the storage period before hatching. On the day of collection, dark-brown and olive eggs were characterised by a similar and significantly higher (by about 48%) number of embryo BCs in comparison with light-brown and blue eggs. Dark-brown eggs stored longer than one day had the highest, while blue-shelled eggs the lowest, number of BCs. The number of BCs found in eggs with blue and light-brown coloured eggshells stored for 10 days was similar and significantly lower (by 27.7%) in comparison with dark-brown eggs. With the lengthening of the storage period, the number of blastodermal cells in eggs of all eggshell colours declined as a result of necrobiosis. In comparison with the dark-brown and olive-shelled eggs, eggs with blue eggshells had higher (by about 7.0%) weight loss during the 21 days until hatching. The dark-brown and olive eggs were found to have a 10.3% higher proportion of eggs considered as fertilised in comparison with the blue-shelled eggs. Eggs with dark-brown shells stored for 2-4 days prior to hatching, in comparison with blue-shelled eggs, had a higher proportion of fertilised eggs. The dark-brown and olive eggs stored for 7 and more days before hatching possessed a higher value of this trait in comparison with the eggs of light-brown and blue eggshells (x = 80.9 against 66.4%). The highest drop in the share of fertilised eggs, which amounted on average to 3.25% for each day of storage, was observed in the blue-shelled eggs. The dark-brown eggs stored for 7 days before being placed in an incubator had higher hatchability from fertilised eggs (by 17.8%) in comparison with the eggs with blue eggshells. In the case of eggs stored for 8 to 10 days, values for this trait were higher for the dark-brown and olive-coloured eggs than for the blue-shelled eggs. The highest mean decrease of chick hatchability from fertilised eggs was observed in the case of the blue-shelled eggs (7.93% for each day). The dark-brown eggs had significantly higher (by about 22.0%) chick hatchability from fertilised eggs than the blue-shelled eggs. Moreover, the dark-brown and olive eggs, in comparison with the blue-shelled eggs, were characterised by a significantly higher hatchability after each period of storage before incubation. The highest negative trend-cycle was observed for eggs with blue shells, while the smallest for olive-shelled eggs. Directly after laying, pheasant eggs differed with regard to the developmental advancement of the blastodermal embryo depending on eggshell colour. Longer storage time caused the numbers of blastodermal cells in eggs to decrease. The group with blue shells had a lower proportion of fertilised eggs and lower hatching results than the dark-brown eggshell group. I...

Hatchability of 69,324 fertilized eggs of White Italian geese from the WD1 maternal strain, selected for egg production, and of 25,226 eggs from the WD3 paternal strain, selected for weight gain, were compared. A significant difference was noted, but its magnitude varied during the reproduction season. Mean results for the WD1 strain (80.9%) were always higher (P < 0.01) than those of WD3 strain (75.8%). To determine the causes of this difference, goose eggs from WD1, WD3, and the Kuban (K) strain that demonstrate high reproductive performance (egg number, fertility, and hatchability) were incubated in a laboratory scale incubator. Embryonic mortality and egg weight loss during incubation were determined. Best hatchability (78.5%) was noted in eggs from K goose strain and the weight loss attained 10.9% of the initial egg weight, until Day 25 of incubation. With the higher egg weight loss in Strains WD1 (11.8%) and WD3 (13.2%), hatchability was diminished to 67.3 and 65.5%, respectively. Better hatchability resulted from lower mortality up to Day 6 of incubation and, especially, between Days 7 and 25 of incubation. The differences found in the egg weight losses and in embryonic mortality suggest a need for adjusting the incubation technique to the particular goose genotype. Embryo cultivation in vitro in plastic containers made the comparison of embryo survival possible, because the interaction of incubator microclimate by eggshell quality was eliminated. The results noted due to strain were ranked in the following order: K, WD1, and WD3. The experimental findings suggest that, apart from that of shell quality effect on various egg weight losses during incubation, there appear to be other factors that cause differences in hatchability of the goose strains studied.

Abstract. The aim of the performed investigations was to compare eggs of Japanese quail layers of different weights with regard to their shape, selected traits of the content following various times of their storage as well as the results of hatchability and body weight of one-day old chicks. Hatching eggs were divided into four groups: group S – up to 10.50 g, group M – from 10.51 to 11.50 g, group L – from 11.51 to 12.50 g and group XL – from 12.51 g. In experiment I, on days: 1, 3, 5, 7 and 10 of storage, the following traits were assessed in 20 eggs from each group: egg weight (g) and yolk and albumen index as well as the number of Haugh units. In experiment II, five hatches were carried out. The total of 480 eggs were incubated in each hatch (120 eggs for each group). On the 15th day of incubation, the eggs were weighed. After hatching, 30 chicks from each group were weighed. Basic hatchability indices were also determined. Eggs with the smallest weight, stored for 1 day, with the smallest yolks were characterized by their highest content contrary to the eggs with the highest weight (the biggest yolks but with their smallest percentage content). In eggs with the higher weight (groups L and XL), a certain increase in weight and proportion (%) of yolk was observed after 3, 5, 7 and 10 days. The highest albumen percentage content was determined in eggs from groups L and XL, whereas in the remaining groups the albumen content was the smallest. With the lengthening of the egg storage, the albumen weight did not undergo significant changes. After one-day storage, the yolk and albumen index as well as Haugh units were slightly higher for eggs of smaller weight than for bigger ones. Eggs from groups S and M were more spherical. Eggs from groups L and XL had smaller weight losses during hatching. Eggs from group L were characterized by the best fertilization, hatchability results and proportion of dead embryos and unhatched chicks. The heaviest chicks were obtained from eggs of the highest weight, while the lightest – from eggs of the smallest weight. The obtained results appear to indicate that Japanese quail eggs of 10.51-12.50 g are the best for hatching.

ROSIÑSKI A., NOWACZEWSKI S., KONTECKA H., BEDNARCZYK M., ELMINOWSKA-WENDA G., BIELIÑSKA H., M¥CZYÑSKA A. 2006. Analysis of the laying rhythm and reproductive traits of geese. Folia biol. (Kraków) 54: 145-152.The aim of the performed investigations was to analyse the laying rhythm and reproductive traits of Ko³uda ® white geese from the W11 reproduction strain and to determine the heritability of these traits as well as correlations between the laying rhythm traits and reproductive traits. The total number of geese participating in the experiment included 383 one-year old layers from the control flock (the first year of reproductive utilisation). The following traits characterizing the laying rhythm were assessed individually for each layer: the number of 2 and 3-egg clutches or more, length (in days) of 2-or more egg clutches as well as the length of intervals between the laid eggs during the entire laying period. The following reproductive traits were also assessed individually for each bird: age at sexual maturity, initial number of eggs (eggs laid during the period from January, 1 st to April, 30 th ), number of eggs during the whole laying period, laying intensity (the total number of eggs x 100 / length of the laying period in days) as well as the length of the reproductive period. It was found that Ko³uda ® white geese laid most of their eggs (on average 70.2 %) singly and not in clutches. With regard to egg clutches, it was found that 2-egg clutches constituted 85.3 % of eggs laid in clutches. Moderate or high variability of traits associated with the laying rhythm and reproduction were demonstrated. The observed moderate heritability of the laying rhythm traits indicate that they may be utilised in the selection programs for geese. On the other hand, the reported high, positive genetic correlation coefficients between the number of egg clutches and the initial and total egg number as well as laying intensity confirm the existence of interactions between these traits. This fact may be helpful in breeding programs for determining the optimal selection systems for geese.