Progress 07/01/07 to 06/30/13
Outputs
Target Audience: This project is intended to target poultry scientists and the poultry industry by improving fertility and embryonic mortality and therefore lowering the cost of poultry to the consumer. This audience was reached by presenting data in the classroom, at poultry industry meetings, at scientific meetings and publishing results in scientific journals. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? A graduate student and several undergraduate students were provided laboratory training on proper data collection and analysis. Additionally, a graduate student was trained in presentation of research data at scientific meetings and research manuscript preparation. How have the results been disseminated to communities of interest? In addition to presenations of this data at scientific conferences, results of this research have been presented to members of the poutlry industry at both formal and informal meetings. What do you plan to do during the next reporting period to accomplish the goals? This project has been terminated and a new project on parthenogenesis has been initiated.
Impacts
What was accomplished under these goals?
The first major accomplishment was in addressing the 3rd goal of this project. Therefore, the objective of this study was to determine if storage and incubational temperatures impact the incidence and size of parthenogenetic development in Chinese Painted quail eggs. Virgin quail hens were individually caged, and eggs were collected and labeled daily. Eggs were divided among 3 different storage temperatures (20, 30 or 40ºC). After storage, eggs from each storage temperature were divided between 2 incubational temperatures. One half of the eggs were incubated at 37ºC for 10 d, and the other half of the eggs were incubated at 42ºC for 48h then returned to the standard incubational temperature of 37ºC for the remaining 8 d of incubation. After 10 d of incubation, albumen pH was measured for each egg, and embryo size was determined for eggs exhibiting parthenogenesis. At an incubational temperature of 42ºC, eggs stored at 30ºC yielded a lower percentage of parthenogens than eggs stored at 20ºC. However when eggs were stored at 20ºC, incubation at 37ºC yielded a higher albumen pH than incubation at 42ºC. As storage temperature increased, parthenogen size increased when eggs were incubated at 37ºC. Also when eggs were stored at 30ºC, embryo size was larger with incubation at 42ºC as compared to incubation at 37ºC. In conclusion, both egg storage temperature and incubational temperature impact the incidence of parthenogenesis and the size of the parthenogenetic embryo. The second major accomplishment was in addressing the 4th and 5th goals of this project. Therefore, the objective of this study was to determine if genetic selection for parthenogenesis in Chinese Painted quail affects hatchability. At 4 wk of age, females were separated from males and individually caged. Daily, eggs were collected, labeled, and stored from 0-3 d at 20°C then incubated at 37.5°C. At day 10 of incubation, eggs from virgin hens were broken out to determine the incidence of parthenogenesis. After the incidence of parthenogenesis in virgin hens was determined, they were selected for mating. Eggs from the parent (P) stock and generations 1 through 7 that did not hatch were examined for stage of hatching failure and categorized as infertile or possible parthenogens as well as early, middle, and late embryonic mortality. For hatch of set and hatch of fertile eggs, generation 1 hatched the greatest percentage of eggs when compared to the other generations. Also, as the generation of selection increased, there was a linear decline in the percentage of eggs hatched for both hatch of set and hatch of fertile eggs. Additionally, generation 2 had the highest percentage of infertile eggs. There was a linear increase as generation of selection increased for both the percentage of eggs exhibiting possible parthenogens and early embryonic mortality. Unlike early embryonic mortality, the P generation had the greatest percentage of embryos die in both the middle and late stage of incubation. In conclusion, it appears that selecting Chinese Painted quail for the parthenogenetic trait impairs hatchability when hens are mated.
Publications
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2013
Citation:
Santa Rosa, P., H. Parker, A. Kiess, and C. McDaniel, 2013. Egg storage and incubational temperatures impact parthenogenetic development in Chinese Painted quail eggs. Poult. Sci. 92 (E-suppl. 1): 233.
- Type:
Journal Articles
Status:
Under Review
Year Published:
2013
Citation:
Parker, H. M., A. S. Kiess, B. E. Starkey, P. Santa Rosa, D. Rowe and C. D. McDaniel. 2013. Selection for the parthenogenetic trait in Chinese Painted Quail (Coturnix chinensis)and its effect on hatchability parameters by generation. Poult. Sci 91: (under review).
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Progress 01/01/12 to 12/31/12
Outputs
OUTPUTS: Parthenogenesis is spontaneous embryonic development of an unfertilized egg, and within the commercial turkey industry approximately 4% of unfertilized eggs exhibit embryonic development. More recently parthenogenesis has been reported in Chinese Painted Quail eggs. In Japanese quail, it has been shown that albumen pH of incubated fertile eggs is lower than that of incubated infertile eggs. However, it is unknown if alterations, similar to those in incubated fertile eggs, occur in albumen pH or ion concentrations within unfertilized eggs exhibiting parthenogenetic development. Therefore two studies were conducted. The objective of the first study was to determine if any differences in pH or ion concentrations exist between incubated unfertilized eggs containing parthenogenetic development on the tenth day of incubation versus unfertilized eggs with no development on the tenth day of incubation. The objective of the second study was to determine changes in albumen pH, gas, and ion concentrations due to parthenogenesis on each of the first 12 days of incubation. PARTICIPANTS: Dr. Chris McDaniel-PI, Dr. Holly Parker-Senior Research Associate, Dr. Aaron Kiess-collaborator, Mrs. Jessica Wells-collaborator, Ms. Monica Robertson-graduate student, Ms. Priscila Santa Rosa-graduate student. TARGET AUDIENCES: This project is intended to target poultry scientists and the poultry industry by improving fertility and embryonic mortality and therefore lower the cost of poultry to the consumer. This audience was reached by presenting data in the classroom, at poultry industry meetings, at scientific meetings and publishing results in scientific journals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
In the first study, eggs were collected daily from Chinese Painted Quail hens that were separated from males at 4 weeks of age, prior to sexual maturity. Eggs were stored for 0 to 3 days at 20C and incubated at 37.5C. To determine egg weight loss, eggs were weighed prior to setting and then again after 10 days of incubation. After 10 days of incubation, oxygen, calcium, sodium and chloride concentrations as well as pH were obtained from the albumen of each incubated egg. For unfertilized eggs containing parthenogens, there was less egg weight loss when compared to unfertilized eggs with no development. Albumen from unfertilized eggs with parthenogenetic development also exhibited a lower pH as well as less oxygen and chloride when compared to the albumen of unfertilized eggs with no development. However, albumen from unfertilized eggs with parthenogenetic development yielded higher concentrations of calcium and sodium when compared to the albumen of unfertilized eggs with no development. For the second study, Chinese Painted quail hens (137) were also separated from males and individually caged prior to sexual maturity. Eggs were collected daily, stored for 0 to 3 days at 20C and incubated at 37.5C for 1 to 12 days of incubation before being broken open for analysis. Unfertilized eggs were examined from 0 through 12 days of incubation for the occurrence of embryonic development as well as albumen pH, oxygen, carbon dioxide, calcium, sodium, and chloride concentrations. Eggs exhibiting parthenogenesis had lower albumen pH, oxygen and chloride concentrations yet higher carbon dioxide, calcium and sodium concentrations over the entire length of incubation as compared to eggs with no parthenogenetic development. As incubation progressed, eggs that did not contain parthenogens exhibited decreasing oxygen concentrations, yet pH, calcium, and chloride concentrations increased. However, as the length of incubation increased in eggs containing parthenogenetic development, pH, oxygen and carbon dioxide concentrations decreased, yet calcium increased much more rapidly over incubation than in eggs with no development. Interestingly, as parthenogen size increased, the concentration of carbon dioxide in albumen also increased, yet pH and oxygen decreased. In conclusion, it appears from the first study that parthenogenetic development after 10 days of incubation alters the ionic composition of albumen from unfertilized eggs as compared to the albumen from unfertilized eggs with no parthenogenetic development. As seen in the second study, eggs exhibiting parthenogenetic development continue to alter albumen pH, gas exchange, and ionic composition as incubation increases when compared to eggs with no parthenogenetic development. Also, results from second study indicate that some parthenogens are viable and modifying the ionic and gaseous content of the egg throughout incubation even though normal embryonic differentiation has not occurred.
Publications
- Parker, H. M., A. S. Kiess, M. L. Robertson, J. B. Wells, and C. D. McDaniel. 2012. The relationship of parthenogenesis in virgin Chinese Painted quail (Coturnix chinensis) hens with embryonic mortality and hatchability following mating. Poult. Sci. 91: 1425-1431.
- Santa Rosa, P., H. M. Parker, A. S. Kiess, and C. D. McDaniel, 2012. Parthenogenetic development in incubated unfertilized Chinese Painted Quail eggs alters pH and ion concentrations in egg albumen. Poult. Sci. 91 (E-suppl. 1): 250.
- Santa Rosa, P., H. M. Parker, A. S. Kiess, and C. D. McDaniel, 2012. Parthenogenetic embryos from unfertilized Chinese Painted quail eggs alter albumen pH, gas, and ion concentrations during incubation. Poult. Sci. 91 (E-suppl. 1): 151.
- Wells, J. B., H. M. Parker, A. S. Kiess, and C. D. McDaniel, 2012. The relationship of incubational egg weight loss with parthenogenesis in Chinese Painted quail (Coturnix chinensis). Poult. Sci. 91:189-196.
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Progress 01/01/11 to 09/30/11
Outputs
OUTPUTS: Unfertilized chicken, turkey, and quail eggs are capable of developing embryos by parthenogenesis. Recently, we revealed that eggshell quality influences the incidence of parthenogenesis in Chinese Painted quail eggs because as the percentage of egg water loss decreases, the incidence of parthenogenesis increases. Of course, eggshell quality is also of utmost importance to hatchability of fertilized eggs. However, it is unknown if the physiological mechanisms regulating and impacting parthenogenesis, including possibly eggshell quality, in virgin hens may actually work against fertilization, embryonic development and hatchability of eggs from these same hens following mating. Additionally, because most parthenogenic development closely resembles early embryonic mortality in fertilized eggs during the first 2-3 d of incubation, it is possible that many unhatched eggs classified as containing early dead embryos may actually be unfertilized eggs that contain parthenogenic development. Finally, parthenogenesis in birds can also be controlled by genetic selection. However, it is unknown if genetic selection for parthenogenesis affects embryonic development and hatchability of fertilized eggs. Therefore the objectives of this study were, first, to examine the relationship of parthenogenesis prior to mating with embryonic development and hatchability characteristics after mating and, secondly, to determine if genetic selection for parthenogenesis in virgin hens would impact embryonic development and hatchability after mating. PARTICIPANTS: Dr. Chris McDaniel-PI, Dr. Holly Parker-Senior Research Associate, Dr. Aaron Kiess-collaborator, Mrs. Jessica Wells-collaborator, Ms. Monica Robertson-graduate student TARGET AUDIENCES: This project is intended to target poultry scientists and the poultry industry by improving fertility and embryonic mortality and therefore lowering the cost of poultry to the consumer. This audience was reached by presenting data in the classroom, at poultry industry meetings, at scientific meetings and publishing results in scientific journals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
For the first objective, 340 virgin Chinese painted quail hens were divided into 7 groups, based upon their ability to produce unfertilized eggs that exhibit parthenogenesis, as follows: 0, 10, 20, 30, 40, 50, and 60% or greater parthenogenesis. Males were then placed with these hens so that fertility, embryonic mortality, and hatchability could be evaluated for each hen. Hatchability of eggs set, hatchability of fertile eggs, and late embryonic mortality decreased dramatically as the incidence of parthenogenesis increased. On the other hand, early embryonic mortality increased as parthenogenesis increased. Fertility was not different across the 7 parthenogenesis hen groups perhaps because unfertilized eggs that exhibited parthenogenesis resembled and were therefore classified as early embryonic mortality. For the second objective, 307 virgin Chinese Painted quail hens were utilized across 5 generations of selection, based upon their ability to produce unfertilized eggs that exhibited at least 10% parthenogenesis. In the first generation (P), random males were selected for mating. However, for subsequent generations (F1 to F5), males whose sisters or mothers exhibited parthenogenesis were mated to hens so that fertility, embryonic mortality, and hatchability could be evaluated. Early embryonic mortality was divided into 2 groups: ≤7mm (small early dead embryos, possible parthenogens) and > 7 mm (large early dead embryos). After the F1 generation of selection, hatch of eggs set and hatch of fertile eggs decreased. The P generation had fewer possible parthenogens than did the F5 generation, yet both generations were similar for large early embryonic mortalities, middle deads, and cracked eggs. The P generation had more late embryonic mortality and contaminated eggs than the F5 generation. Fertility was not different across generation of selection, perhaps because many unfertilized eggs that exhibited parthenogenesis resembled early embryonic mortality and therefore were classified as early embryonic mortality. In conclusion, virgin quail hens that exhibit parthenogenesis appear to have impaired embryonic development and hatchability following mating. Additionally, sperm egg interaction and embryonic research is needed to determine if a large portion of the early embryo death experienced by virgin hens exhibiting parthenogenesis is in fact infertility. Also, genetic selection for parthenogenesis in virgin quail hens appears to impair hatchability and early embryonic development following mating. Because parthenogenesis appears to work against normal fertilization and embryonic development, poultry breeding companies should consider genetic selection against parthenogenesis in breeding stock.
Publications
- Wells, J. B., H. M. Parker, A. S. Kiess, and C. D. McDaniel, 2011. The relationship of incubational egg weight loss with parthenogenesis in Chinese Painted quail (Coturnix chinensis). Poult. Sci. 90: (In Press).
- Parker, H.M., A.S. Kiess, J.B. Wells, M.L. Robertson, and C.D. McDaniel. 2011. Genetic selection for parthenogenesis in virgin quail hens impact embryonic mortality and hatchability following mating. Poult. Sci. 90 (E-suppl. 1): 99.
- Robertson M.L., H.M. Parker, J.B. Wells, A.S. Kiess, and C.D. McDaniel. 2011. The relationship of parthenogenesis in virgin quail hens with embryonic mortality and hatchability following mating. Poult. Sci. 90 (E-suppl. 1): 218.
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Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: Parthenogenesis, the development of an unfertilized egg, has been studied extensively in turkeys. Recently we revealed that parthenogenesis occurs in the eggs of Chinese painted quail. In fact, we have demonstrated that genetic selection for parthenogenesis in the Chinese painted quail increased the incidence of parthenogenesis and embryonic size but decreased egg production and average position of an egg in a clutch as generations of selection increased. Additionally, the percentage of eggs exhibiting parthenogenesis is negatively correlated with egg production as well as clutch size. In broiler breeders, it has been reported that the first egg of a sequence loses less moisture, and therefore weight, during incubation. Because the incidence of parthenogenesis is greater and egg weight loss is less in the first egg of a sequence, it is possible that parthenogenesis is also affected by egg moisture loss. Therefore, the objective of this study was to determine if a relationship exists between egg moisture loss and parthenogenesis. PARTICIPANTS: Dr. Chris McDaniel-PI, Dr. Holly Parker-Senior Research Associate, Dr. Aaron Kiess-collaborator, Mrs. Jessica Wells-collaborator, Dr. Dennis Rowe-collaborator, Ms. Kathy Young-graduate student TARGET AUDIENCES: This project is intended to target poultry scientists and the poultry industry by improving fertility and embryonic mortality and therefore lowering the cost of poultry to the consumer. This audience was reached by presenting data in the classroom, at poultry industry meetings, at scientific meetings and publishing results in scientific journals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
In this experiment, individual eggs from 157 hens were collected daily and labeled with hen number and date. Eggs were stored for 0 to 3 d at 20 C before incubation at 37 C. To determine egg weight loss, eggs were weighed on the day of collection and again after 10 d of incubation. Pearson's correlation coefficients were used to determine if relationships exist between egg weight loss and the percentage of eggs exhibiting parthenogenesis, parthenogen size, egg storage, and clutch position. The percentage of egg weight loss was negatively correlated with the incidence of parthenogenesis in eggs (r=-0.56; P<0.001), parthenogen size(r=-0.49; P<0.001), and egg storage (r=-0.24; P<0.003). However, the percentage of egg weight loss was positively correlated with average clutch position (r=0.32; P<0.001). In conclusion, it appears that eggshell quality, as determined by incubational egg weight loss, influences the incidence of parthenogenesis in Chinese Painted quail eggs because as the percentage of egg weight loss decreases, the incidence of parthenogenesis increases. Quail hens with poor egg production exhibit the greatest amount of parthenogenesis. Because modern broiler breeder chickens also have poor egg production, it is possible that parthenogenesis may be present in these birds as well and may affect normal embryonic development of fertilized eggs. Results from the present study clearly demonstrate that incubational egg weight loss directly impacts the incidence of parthenogenesis. Therefore, this information may be useful in improving hatchability of commercial chickens, because modification of incubator humidity levels to alter incubational egg weight loss may likely impact parthenogenesis.
Publications
- Parker, H. M., A. S. Kiess, J. B. Wells, K. M. Young, D. Rowe, and C. D. McDaniel, 2010. Genetic selection increases parthenogenesis in Chinese Painted Quail (Corturnix chinensis). Poult. Sci. 89: 1468-1472.
- Wells, J. B., H. M. Parker, A. S. Kiess, and C. D. McDaniel, 2010. The Effect of Egg Weight Loss on Embryonic Development in Chinese Painted Quail (Coturnix chinensis) Exhibiting Parthenogenesis. Poultry Sci 89 (suppl 1):288.
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Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: Parthenogenesis, embryonic development of an unfertilized egg, occurs naturally in turkey, chicken, and quail species. In fact, parthenogenesis in turkeys and chickens can be increased by genetic selection. However, it is unknown if genetic selection for parthenogenesis is effective in quail or if selection for parthenogenesis affects egg production. Therefore, the objectives of this study were to determine if the incidence of parthenogenesis in quail could be increased by genetic selection and if selection for this trait impacts egg production. To prevent fertilization, 1090 females were caged separately from males at 4 wk of age and then caged individually at 6 wk of age to monitor egg production. Eggs were collected daily, labeled and stored for 0 to 3 d. After 10 d of incubation, 20 unfertilized eggs from each hen were examined for the occurrence of parthenogenesis and embryonic growth. In the P generation (P) and subsequent generations (1 to 4), hens laying eggs containing parthenogenetic development and males whose sisters or mothers exhibited parthenogenesis were used for breeding. PARTICIPANTS: Dr. Chris McDaniel-PI, Dr. Holly Parker-Research Associate III TARGET AUDIENCES: This project is intended to target poultry scientists and the poultry industry by improving fertility and embryonic mortality and therefore lowering the cost of poultry to the consumer. This audience was reached by presenting data in the classroom, at poultry industry meetings, at scientific meetings and publishing results in scientific journals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
There was a linear increase in the percentage of hens exhibiting parthenogenesis as generation of selection increased. With each successive generation, there was a quadratic response in the percentage of eggs positive for parthenogenesis. When compared to the P generation, parthenogenesis was almost 3 times greater for eggs laid by the 4th generation (4.6 to12.5%, respectively). Even when only hens exhibiting parthenogenesis were examined, the percentage of eggs demonstrating embryonic development responded quadratically with generation of selection. The embryonic size at 10 d of incubation was greater for each subsequent generation when compared to the P generation. There was a linear decrease in both egg production and the average position of an egg in a clutch as generation of selection increased. In conclusion, genetic selection for parthenogenesis increased the incidence of parthenogenesis and embryonic size but decreased egg production and average position of an egg in a clutch as generations of selection increased. It is interesting to note that in the current study when hens were selected for parthenogenesis egg production declined. Because modern broiler breeder chickens also have poor egg production, it is possible that parthenogenesis may be present in these birds as well and may affect normal embryonic development of fertilized eggs. Therefore, this information may be useful in improving fertility and embryonic survival rates of commercial chickens, through genetic selection.
Publications
- Parker, H. M. and C. D. McDaniel, 2009. Parthenogenesis in unfertilized eggs of Coturnix chinensis, the Chinese Painted Quail, and the effect of egg clutch position on embryonic development. Poultry Science 88: 784-790.
- Parker, H. M., A. S. Kiess, J. B. Wells, K. M. Young, and C. D. McDaniel, 2009. Genetic selection increases parthenogenesis in Chinese Painted Quail (Coturnix chinensis). Poultry Sci. 88:(pending).
- Parker, H.M., and C. D. McDaniel, 2009. Genetic selection increases parthenogenesis in Chinese Painted Quail (Coturnix chinensis). Poultry Science 88 (suppl 1):163.
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: Avian parthenogenesis, embryonic development of unfertilized eggs, was first discovered in the Beltsville Small White turkey. Recently, we discovered that approximately 4% of unfertilized Chinese painted quail eggs contained embryos upon incubation. However, the size and morphology of parthenogenetic quail embryos is unknown. Secondly, it is unknown if a relationship exists between parthenogenesis and egg production. To obtain unfertilized eggs, hens (300) were separated from males at 4 wk of age when adult male plumage first became visible. Each hen was individually caged at 6 wk of age so that initial egg production could be obtained. Daily, individual eggs were collected, labeled, and stored for 0 to 3 d at 20 C. Eggs were incubated at standard conditions (37.5 C) for 10 d. The first 20 eggs laid by each hen over a 90 d period were examined at 10 d of incubation for embryonic development using a magnifying lamp at 2x magnification. Embryonic development was measured to the nearest millimeter, across the greatest width of the blastodisc. To determine the amount of embryonic development for parthenogens, the sizes of the parthenogens were compared to the size of the blastoderms or germinal discs of fresh unincubated-fertilized eggs from hens housed with males, fresh unincubated-unfertilized eggs, and unfertilized eggs without parthenogens that had been incubated for 10 d (n=145 eggs/group). For our second objective, Pearson's correlation coefficients were obtained for the relationships of hen-day egg production with eggs positive for parthenogenetic development and parthenogen size. Correlation coefficients were also used to determine the relationship of mean clutch size with the percentage of eggs positive for parthenogenetic development and parthenogen size. PARTICIPANTS: Dr. Chris McDaniel - PI, Dr. Holly Parker - Research Associate III TARGET AUDIENCES: This project is intended to target poultry scientists and the poultry industry by improving fertility and embryonic mortality and therefore lowering the cost of poultry to the consumer. This audience was reached by presenting data in the classroom, at poultry industry meetings, at scientific meetings and publishing results in scientific journals. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The germinal disc of fresh unincubated-fertilized Chinese Painted quail eggs contained an area pellucida, area opaca, and periblastic ring. However, the area pellucida, area opaca, and a distinct periblastic ring were absent from the fresh unincubated-unfertilized germinal discs. The unincubated-unfertilized germinal discs contained numerous small vacuoles. Unfertilized germinal discs incubated for 10 d exhibited degradation with even more vacuoles than unincubated-unfertilized germinal discs. Unorganized sheets of epithelial cells could be seen engulfing the egg yolk of eggs containing unorganized, undifferentiated parthenogenetic development after 10 d of incubation. A few unfertilized eggs incubated for 10 d exhibited more organized parthenogenetic development as evidenced by a germinal disc containing an area pellucida, area opaca, and periblastic ring. The mean germinal disc size for unincubated-fertilized eggs (3.93 mm, ) was significantly wider than the germinal disc size of unincubated-unfertilized, 10 d incubated-unfertilized, and the 10 day incubated-parthenogen (2.56, 2.06, and 3.73, respectively; P<0.0001). However, germinal discs were wider for 10 d incubated parthenogens when compared to discs of either unincubated-unfertilized or 10 d incubated-unfertilized eggs. Also, the discs from unincubated-unfertilized eggs were wider than those of 10 d incubated-unfertilized eggs. However, very few quail blastodiscs that developed parthenogenetically had organized development with an area opaca, area pellucida, and a distinct periblastic ring. In fact, the vast majority of germinal discs exhibiting parthenogenetic development contained unorganized, membranous, undifferentiated cells. For the second objective, the correlation coefficient for mean clutch size with percentage of eggs positive for parthenogenesis was negative (r = -.16). For example, when the incidence of parthenogenesis was greater than 40%, mean clutch size was 1.4, which was approximately 2 eggs less than the overall mean clutch size of 3.3 eggs. Even though there was a relationship for mean clutch size with percentage of eggs positive for parthenogenesis, no relationship was detected for parthenogenetic germinal disc width with clutch position. In conclusion, quail parthenogens in eggs incubated 10 days are most often very unorganized and about the same size as embryos from fresh fertilized eggs. Hens with poor egg production exhibit the greatest amount of parthenogenesis. Because modern broiler breeder chickens also have poor egg production, it is possible that parthenogenesis may be present in these birds as well and may affect normal embryonic development of fertilized eggs. Therefore, this information may be useful in improving fertility and embryonic survival rates of commercial chickens, through genetic selection.
Publications
- Wells, J., C. Coufal, H. Parker, and C. McDaniel, 2008. Disinfection of eggshells using ultraviolet light and hydrogen peroxide independently and in combination. Poultry Science 87 (suppl. 1):143.
- Wells, J., C. Coufal, H. Parker, and C. McDaniel, 2008. Effects of eggshell sanitation using ultraviolet light and hydrogen peroxide in combination on hatch parameters of broiler breeder eggs. Poultry Science 87 (suppl. 1):47
- Coufal, C., J. Wells, H. Parker, and C. McDaniel, 2008. Effects of ultraviolet light irradiation on hatchability of floor eggs from White Leghorns. Poultry Science 87 (suppl. 1):161.
- Parker, H. M. and C. D. McDaniel, 2008. Parthenogenesis in unfertilized eggs of Coturnix chinensis, the Chinese Painted Quail, and the impact of egg clutch position on embryonic development. Poultry Science 87: (accepted and in press)
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Progress 07/01/07 to 12/31/07
Outputs
OUTPUTS: Parthenogenesis, embryonic development of an unfertilized egg, has been studied for many years in turkeys. In fact, as many as 49% of unfertilized Beltsville Small White turkey eggs develop embryos. However, virtually no research exists on parthenogenesis in quail. The Chinese painted quail is a close relative of the more common Japanese quail and, unlike turkeys or chickens, the small Chinese painted quail reaches sexual maturity rapidly, making it a great candidate for further research on parthenogenesis. Obviously, a better understanding of avian parthenogenesis will increase our knowledge of avian fertilization and early embryonic development. Therefore we determined if unfertilized Chinese painted quail hens produce embryos. Secondly, we explored the possibility that position of the egg within the clutch influenced the rate of parthenogenesis. When initial secondary sexual plumage was apparent at 4 wk of age, male chicks were separated from females to prevent fertilization. Hens were placed in individual cages near sexual maturity, at approximately 8 wk of age. Individual eggs were collected daily and labeled with the hen number and date. Eggs were stored for 0 to 3 days at 20 C prior to incubation at 37.5 C. After 10 days of incubation, approximately 8,000 eggs from 308 laying hens were examined for embryonic development under a magnifying lamp. PARTICIPANTS: Dr. Chris McDaniel - PI, Dr. Holly Parker - Research Associate III TARGET AUDIENCES: This project is intended to target poultry scientists and the poultry industry by improving fertility and therefore lowering the cost of poultry to the consumer. This audience was reached by presenting this research at the International Poultry Scientific Forum. PROJECT MODIFICATIONS: No Project Modifications information reported.
Impacts
On average, 4% of the unfertilized quail eggs in this study contained embryonic development consisting solely of unorganized membranes. About 37% of the laying hens produced at least one parthenogenetic embryo. However, about 9% of the hens exhibited a predisposition for parthenogenesis by producing 4 or more unfertilized eggs with embryos. One hen even produced 8 embryos from 25 unfertilized eggs laid. Additionally, the first egg laid in a clutch was most likely to produce an embryo, with a steady decline in the percentage of eggs developing embryos as position in the clutch increased. In conclusion, the Chinese painted quail does exhibit parthenogenesis and appears to be an excellent new animal model for studying parthenogenesis. It is hoped that poultry scientist may use this information to improve fertility in domestic poultry species. Additionally because early embryonic mortality and parthenogenetic embryos are similar in stage of development at death, research with this newly discovered model animal for parthenogenesis may help researchers improve early embryonic mortality as well.
Publications
- McDaniel, C. D. and H. M. Parker, 2007. Parthenogenesis discovered in unfertilized eggs of Coturnix chinensis, the Chinese painted quail. Poult. Sci. 86 (suppl 1): 725.
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