Effects of broiler breeder strain, age, and eggs preheating profile in single-stage systems on the hatchability of eggs and quality of chicks.

Preheating can increase the efficiency of commercial broiler breeding. A slow increase in temperature can counteract the negative effects of water condensation on the surface of the shell and reduces the thermal shock to the embryos. It is essential to design different preheating profiles because of the variances between breeds in terms of egg construction and the course of embryogenesis, along with the influence of the parental flocks' age on hatching rates. This study aimed to analyze six preheating profiles with different time and temperature patterns (A-F), which were immediately applied before the egg incubation began. These profiles were used for two broiler breeder strains - Hubbard Flex and Ross 308 - for the entire laying cycle divided into six age ranges: 25-30, 31-36, 37-42, 43-48, 49-54, and 55-60wk of life. A total of 7839250 Hubbard Flex and 57167060 Ross 308 eggs were used in the study. The eggs were stored for 4-7d before the preheating profile was applied. Mortality during incubation, hatchability, and the quality of chicks were analyzed. The most favorable results were obtained with profile B - 02 h (25.0 °C):02 h (29.4 °C):02 h (32.2 °C):02 h (35.0 °C):02 h (37.8 °C), while the worst results were obtained with profile C - 03 h (23.9 °C):03 h (25.0 °C):04 h (32.2 °C). These findings indicated that compared to a rapid temperature increase during incubation, multistage slow heating of eggs is more advantageous as it enables achieving better hatchability from apparent fertile eggs and obtaining more first-grade chicks. An analysis of the interaction of different preheating profiles with flock age and breed of parental flock revealed that profile C is not suitable for eggs from older flocks, in particular Ross 308. Deterioration of hatchability of chicks from apparent fertile eggs was also confirmed for flocks over 49wk of life after the application of profile E - 03 h (77 °C):02 h (29.4 °C):02 h (32.2 °C):01 h (35.0 °C):02 h (37.8 °C). Increased early and late mortality of embryos was observed in the case of Hubbard Flex after the use of profile D - 03 h (25.0 °C):02 h (29.4 °C):01 h (32.2 °C):02 h (35.05 °C):02 h (37.8 °C). Based on the obtained results, it can be recommended that profile B can be applied for the entire duration of Ross 308 and Hubbard Flex flock utilization to achieve high egg hatchability and obtain high-quality chicks.

Effect of dietary canthaxanthin and iodine on the production performance and egg quality of laying hens.

In this study, we aimed to evaluate the effect of canthaxanthin (CX) and iodine (I) on the production of laying hens, on counteracting debilitation of the vitelline membrane, and on inhibiting Salmonella growth in eggs stored at 30°C. Three hundred hens were reared in cages. Birds were divided into six feeding groups (10 hens × 5 repetitions) that were administered 0, 3 or 6 ppm of CX and 1 or 10 ppm of I with their diets. Laying rate, egg weights, and feed conversion ratios were controlled. The quality of fresh eggs was assessed in wks 25-26, 48-50 and 62-63 of hens lives. An additional batch of eggs was incubated at the temperature of 30°C, and egg quality changes were monitored on days 3, 6 and 9 of storage. Additionally, eggs collected from four experimental groups of hens whose diets had been iodated with 1 or 10 ppm of I and supplemented with 0 or 6 ppm of CX were infected under laboratory conditions with Salmonella, and incubated for 5 and 10 d. The laying rate, egg weights, and feed conversion ratio were significantly improved. Dietary inclusion of CX contributed to a higher resistance of the vitelline membrane of egg yolks, but only for fresh eggs. Vitelline membrane degradation during egg storage at 30°C was significantly counteracted by dietary inclusion of I at a dose of 10 ppm. The same I dose resulted in the complete inhibition of Salmonella growth until day 10 of incubation, but exclusively for eggs collected from 40-week-old hens. Dietary supplementation with 10 ppm of I was found to impart high level of resistance to the vitelline membrane against the growth of Salmonella in case of eggs stored at 30°C; therefore, I was found to be more beneficial by ensuring longer preservation than that of CX. However, dietary supplementation with CX was found to increase the resistance of vitelline membrane in fresh eggs.

Short periods of incubation, egg turning during storage and broiler breeder hens age for early development of embryos, hatching results, chicks quality and juvenile growth.

An effect of modification of storage conditions of the eggs of broiler breeder flocks at the age of 49-, 52- and 70-, 73-wks of life on an early embryonic development, hatching time and synchronization, hatchability rates, chicks quality and broiler growth was investigated. The eggs were divided into 4 experimental groups: COI = eggs storage 5 d, at turning every 12 h; NSP = eggs storage 12 d, at turning every 12 h; SPIDES = were treated with 4 h pre-incubation at 30°C and 50-55% air humidity, delivered at 5 and 10 d over of 12 d of storage, and turning every 12 h; NCOI = eggs storage 12 d, no turning and no pre-incubation. Eggs from older hens were characterized by poorer hatchability and poorer chicks quality. The use of 2 × 4 h pre-incubation in 12 d of eggs storage could have an effect on the initial acceleration of embryonic development in eggs of young hens, contributing to the alignment of embryos development in eggs from young and older hens to 72 h of incubation. Pre-incubation had no effect on the length of incubation period, hatching window, but it increased the hatchability of the set and apparently fertilized eggs and decreased the number of eggs not hatched, and also improved chicks quality. Eggs turning by 90° every 12 h during the storage positively affected the embryonic development, shortening the incubation time and the quality of chicks, but had no effect on hatchability rates and body weight in 42 d of life. Based on the obtained results, it can be concluded that the applied modifications can be effective in counteracting the negative effects of storage of hatching eggs from both young and older birds.

Early and 24 h post-mortem thigh (ilio tibialis) muscle metabolism and meat quality in two genetic types of turkeys and their reciprocal crosses, raised under semi-confined conditions.

1. The experiment was conducted in order to determine the effect of the direction of turkey crossing on quality traits of their thigh muscle. 2. In total, 1358 turkeys of slow- (SG) and fast-growing (FG) lines as well as SF crosses (SG × FG) and FS crosses (FG × SG) were reared with access to free range to 21 weeks of age in the case of males and 15 weeks of age in the case of hens. 3. After slaughter of 15 males and 15 hens from each genetic line, their thigh muscles were examined and the following traits were measured after 5-min, 45-min, 2-h and 24-h post-mortem: temperature, pH, glycogen content (G), lactate content (L) and electrical conductivity (EC). Quality attributes were evaluated based on chemical composition, water holding capacity, cooking loss (%) and colour. 4. The rate of post-mortem changes in temperature, G, L and pH in muscles differed among the 4 lines of turkeys, with the highest metabolic rate determined for muscles of SG turkeys, followed by muscles of SF, FS and FG birds. A more beneficial muscle water holding capacity of both sexes of turkeys and better results of cooking loss in male muscles were found in SG and SF turkeys. The thigh muscles of the crosses were characterised by a higher content of protein and a lower content of fat compared to the muscles of FG turkeys, and in the case of the males also by a higher protein content compared to the muscles of SG birds. 5. Owing to the faster post-mortem metabolism, better water holding capacity, lower cooking loss and fat content at a similar content of protein, the thigh muscles of SF crosses raised in the free range system represent a better quality of meat for consumers compared to the thigh muscles of FS turkeys.

Comparative analysis of structure and strength of vitelline membrane and physical parameters of yolk of ostrich, emu, and greater rhea eggs.

In this study, we analyzed selected morphological traits of eggs, as well as structure, strength, and protein composition of the vitelline membrane (VM) of ostrich, emu, and greater rhea eggs. Ninety eggs (30 for species) were analyzed for the following parameters: egg weight, yolk weight, yolk ratio, and yolk index. In addition, pH value, water activity, consistency index, and flow behavior index were determined. The strength of VM was measured using the TA.HDPlus Texture Analyzer. Micrograph images were taken via a scanning electron microscope. Polyacrylamide gel electrophoresis was conducted under denaturing conditions. Ostrich eggs were characterized by the highest egg and yolk weight compared with those of emu and greater rhea eggs, whereas emu eggs had the highest yolk ratio compared with those of ostrich and greater rhea eggs (P > 0.05). Yolk content differed among the species in terms of water activity; it was found to be higher in emu eggs than in ostrich and greater rhea eggs (P > 0.05). Based on flow curves, yolks of the ratites were classified as pseudoplastic non-Newtonian fluids. The consistency index was significantly higher in yolks of ostrich and emu than that of greater rhea eggs, whereas the VM of yolks of greater rhea eggs was the most resistant (had the highest breaking force = 26.4 g). All species differed significantly regarding the structure of VM, the outer layer (OL) in particular, which was found to constitute fibers of various thicknesses that were differently arranged. Fibers of the OL of the VM of emu, whose fibers were the least differentiated but formed the most compact network, were the most diverse in characterization. An electropherogram of the VM of ostrich revealed 11 primary protein bands: 6 for the OL and 5 for the inner layer (IL), that of emu revealed 9 bands: 5 for the OL and 4 for the IL, and that of greater rhea revealed 10 bands: 6 for the OL and 4 for the IL.

Analysis of storage possibility of raw and smoked breast meat of oat-fattened White Koluda® goose based on their quality characteristics.

Raw and smoked (spickgans) fillets of oat-fattened White Koluda® goose were packed in: PET - ethylene terephthalate bags; VSP - 99% vacuum; MAP1 - 80% O2, 20% CO2; MAP2 - 70% N2, 30% O2; MAP3 - 30% O2, 40% N2, 30% CO2, and stored at a temperature of 2°C. On the day of packaging (0 d) and during storage of raw (5, 7, 10 d) and smoked fillets (5, 10, 15 d), the samples were analyzed for weight losses, physicochemical traits, and chemical composition. The study demonstrated the effect of storage time and packaging method on storage yield of raw and smoked fillets. In VSP, the raw fillets were characterized by the lowest amount of leakage, whereas spickgans were characterized by the highest storage yield and weight loss. The analysis of the effect of the modified atmosphere demonstrated the lowest weight loss of raw fillets at, simultaneously, the smallest amount of leakage in MAP1. The spickgans stored in MAP2 showed higher weight, higher yield after storage, and lower storage loss in all terms of analyses compared to MAP1 and MAP3. The greatest cooking loss at simultaneously the lowest pH values was determined for the samples stored in VSP. The WBSF values of raw fillets were decreasing along with storage time, in contrast to WBSF values of spickgans, in which case the value of this parameter increased compared to 0 d. Raw fillets stored in MAP1 and MAP3 were characterized by the most significant increase in the value of L*, by a decrease in the value of a* and an increase in that of b* parameter. Visual assessment of spickgans on 15 d of storage revealed the presence of white sediment on the surface of products, except for the samples stored in VSP. The study demonstrated the effect of storage time on the contents of protein and fat in raw fillets and on the contents of salt and fat in spickgans.

Early and 24 h post-mortem changes in breast muscle quality traits of two turkey genotypes and their reciprocal crosses raised under semi-confined conditions.

An experiment was conducted to determine the effect of reciprocal crossing of turkeys on early and 24 h post-mortem changes in quality traits of their breast muscles. The turkeys of slow-growing (SG) and fast-growing (FG) lines as well as SF (SG × FG) and FS crosses (FG × SG) were reared with access to free range. After slaughter turkey breast muscles were examined in the following terms: 5 min, 45 min, 2 h and 24 h post-mortem, for: temperature, pH, glycogen content (G), lactate content (L) and electrical conductivity (EC). Quality attributes of the breast meat were evaluated based on chemical composition, water holding capacity (WHC), cooking loss (%), shear force (N) and colour (L*, a*, b*). Despite differences in the rate of post-mortem changes, the genotype of turkeys had no significant effect upon many quality traits assessed 24 h post-mortem. Meat of lighter birds (SG and SF) was characterised by a lower fat content but a similar protein content compared to meat of FS and FG turkeys. In addition, meat of males from these groups was darker. Meat from the breast muscles of heavier birds (FS and FG) was harder. Significant negative maternal effects were determined for temperature of meat of both male and female turkeys, for pH2 and EC24 of males as well as for L2, L24 and cooking loss of female meat. Positive heterosis was confirmed only for pH2 of female meat and for G2 of male meat. In summary, the direction of fast- and slow-growing turkey crossing may affect the quality of their meat. However, meat of both types of hybrids reared under semi-confined conditions (with the possibility of using free range) was characterised by appropriate quality parameters.

A case of bronze turkey twins developing from hatching.

A double-yolked egg that was laid by an 11-month-old bronze turkey hen on 2 April, 2013 was reported. The presented case of developing turkey twin embryos is the first ever described case for this species. The egg weighed 125 g and had 74.6 mm in length and 53.0 mm in width. The embryos died between the 23rd and 24th day of incubation. Both twin 1 and twin 2 were fully developed with body weights of: 37.7 g and 40.3 g, respectively. The likely causes of death include inappropriate arrangement of embryos and insufficient gas exchange in the last period of incubation. The embryos were arranged along the long axis of the egg, one underneath the other, and were closely adhering to one another. The twins were different in plumage pigmentation. In twin 1, a spontaneous mutation of plumage pigmentation (B) was observed, whereas twin 2 showed appropriate pigmentation (b+) in respect to parents.