NOWACZEWSKI S., KONTECKA H., KRYSTIANIAK S. 2012. Effect of In Ovo injection of vitamin C during incubation on hatchability of chickens and ducks. Folia biologica (Kraków) 60: 93-97. The aim of the investigation was to ascertain the influence of different doses of vitamin C injected at selected dates of incubation into the eggs of broiler breeders and Pekin ducks on hatchability. The injected vitamin C doses were administered into the air cell on the 13 JD , 15 JD and 17 JD days (3 and 6 mg chickens) and on the 12 JD and 20 JD days (4 and 8 mg ducks) of incubation. In the case of chickens, no significant differences were recorded between the control and experimental groups with regard to hatchability, although the highest value of hatchability from fertilized eggs was determined in the group injected with 6 mg of vitamin C on the 15 JD day of incubation. On the other hand, in ducks, significant differences were found between the control and experimental groups (4 mg of vitamin C administered on days 12 and 20 and 8 mg of vitamin C injected on day 20 of incubation) regarding hatchability. The value of this trait was higher in the group of eggs injected with ascorbic acid in comparison with the eggs which were not treated. On average, the difference amounted to 32.5 percentage points. Similarly, in the case of the number of dead embryos and unhatched chicks, better results were observed in the above-mentioned experimental groups. In summary, vitamin C injected into chicken eggs failed to influence hatchability. In the case of duck eggs, it was demonstrated that their injection on the 20 JD day of incubation with selected doses of vitamin C (4 and 8 mg/egg) improved hatchability by decreasing the proportions of dead and unhatched embryos.

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...

AnAlysis of chAnges in egg quAlity of broiler breeders during the first reproduction periodH e l e n a K o n t e c k a , S e b a s t i a n N o w a c z e w s k i , M a r t a M . S i e r s z u ł a , K a t a r z y n a W i t k i e w i c z Abstract in reproductive flocks of poultry it is very important to obtain a large number of eggs with normal structure, optimal morphological composition and interior quality. these elements have very significant influence on the biological value of the egg, which determines normal development of the embryo. the aim of the study was to analyse the physical characteristics, morphological composition and quality of individual components of the eggs of cobb 500 broiler breeders during the first year of reproduction. the research material was hatching eggs (280 pcs), whose quality was assessed 7 times in the reproductive season at 5-week intervals. the eggs were examined when the hens were aged 26, 31, 36, 41, 46, 51 and 56 weeks (40 eggs for each age). the following characteristics were evaluated: egg weight (g); egg shape index (%); egg specific gravity (g/cm 3 ); shell thickness (mm); average number of pores in the eggshell (pcs/0.25 cm 2 ); yolk, white and shell weight (g) and their percentage in the egg mass; yolk index (%) and the number of haugh units. the investigations proved that as the reproductive season of hens progressed, the weight of their eggs increased. Above all, this was due to the increase in the yolk weight, because its percentage in the egg weight rose with bird age, whereas the percentage of the white decreased. however, as the reproductive season progressed the quality of both the yolk and white deteriorated. no negative relationship between the age of hens and shell quality (weight, thickness) was observed. only when the birds were aged 56 weeks, the shell thickness was found to be significantly smaller.

The tongue in domestic duck, as in other Anseriformes, is characterized by wide variety of shape and mechanical papillae and they fulfill different function during food collection. The present work aims to describe morphological features of the tongue as well as the pace formation of the mechanical papillae during embryonic period. The results may allow to answer whether the tongue in duck is ready to fulfill feeding function after hatching. The study revealed that the particular part of the tongue and the conical papillae of the body develop between 10th and 16th day of incubation, from the caudal part of the body into the rostral part of the tongue. The conical papillae of the lingual prominence in the first row are formed from 11th to 16th day and in the second row at the turn of the 15th and 16th day of incubation. These papillae developed symmetrically from the median part of the lingual prominence, to its edges. The lingual comb, which is used during transport of the food particles, is formed between 16th and 19th day. The present study indicated the morphological changes of the particular part of the tongue and the mechanical papillae were varied between the developmental stages. The morphology of the tongue in the domestic duck is fully developed before hatching and ready to collect food by pecking and grazing. However, filter-feeding mechanism is not still obvious.