Transcriptome analysis of blastoderms exposed to prolonged egg storage and short periods of incubation during egg storage.

Background: Cool temperature egg storage prior to incubation is a common practice in the broiler industry; however, prolonged egg storage causes increased embryonic mortality and decreased hatchability and growth in surviving chicks. Exposing eggs to short periods of incubation during egg storage (SPIDES) reduces the adverse consequences of prolonged storage. SPIDES increases blastodermal cell viability by reducing apoptosis, though the counteracting mechanisms are unclear.

Stage of goose embryo development at oviposition depending on genotype, flock age, and period of laying.

Embryo development and chick quality are influenced by parental genotype, age, nutrition, environment, and flock management. The aim of study was to determine if genotype, age of goose or eggs laid near the onset of egg production vs. eggs laid near the end of reproduction influence the stage of embryo at oviposition.

Low-mobility sperm phenotype in the domestic turkey: Impact on sperm morphometry and early embryonic death.

The sperm mobility assay measures the ability of sperm to swim through a dense layer of Accudenz , and the sperm mobility phenotype has been shown to predict fertility and other sperm performance traits in roosters and turkeys. In this study, we examined turkey sperm morphometry and rates of early embryonic death associated with high- and low-mobility semen. We also assessed whether the hypo-osmotic stress test, which evaluates the structural integrity of the sperm plasma membrane, may be used as a faster and simpler assay for sperm mobility and viability.

Goose embryonic development from oviposition through 16 hours of incubation.

Normal tables provide an objective step-wise description of the morphological development of an embryo. Such tables have been described for the chicken, turkey, quail, and duck embryos, but there is no such staging table for goose embryos. As the goose has one of the longest incubation periods of all the poultry species and embryo mortality during incubation is relatively high, a normal table of goose embryo development would be useful in assessing the morpho-genetic status of the goose embryo before and during incubation.

A comparison of Mott cell morphology of three avian species. II. - Bad behavior by plasmacytes?

Mott cells are atypical plasmacytes recognized microscopically by endoplasmic reticulum (ER) distensions (Russell bodies) a result of retained secretory product (antibody). Originally associated with parasitism, they are observed in a broad spectrum of immunopathology, sometimes involving hypergammaglobulinemia. Few descriptions of Mott cells appear in avian literature.

Observations of turkey eggs stored up to 27 days and incubated for 8 days: embryo developmental stage and weight differences and the differentiation of fertilized from unfertilized germinal discs.

For logistical reasons, egg storage prior to incubation is a growing practice in the commercial turkey industry. Yet the consequence of increasing egg storage over 7 d is a progressive increase in embryo mortality. The objective of this study was to provide the information necessary to differentiate an early dead embryo from an unfertilized egg after 8 days of incubation (DOI).

Impact of broiler egg storage on the relative expression of selected blastoderm genes associated with apoptosis, oxidative stress, and fatty acid metabolism.

Cool temperature storage of eggs prior to incubation is a frequent practice by commercial broiler hatcheries. However, continued storage beyond 7 d leads to a progressive increase in the rate of early embryonic mortality. In this study, we examined the relative expression of 31 genes associated with fatty acid metabolism (8), apoptosis (7), and oxidative stress (16) pathways to better understand the basis of embryo mortality during egg storage.

Lectin staining of the uterovaginal junction and sperm-storage tubule epithelia in broiler hens.

Mammalian sperm bind to terminal carbohydrates associated with glycoconjugates on the apical surface of oviduct epithelial cells in the caudal region of the oviduct and undergo cellular and molecular modifications associated with capacitation prior to ovulation. In contrast, chicken sperm are stored for up to 23 d in sperm-storage tubules (SST) localized in the uterovaginal junction (UVJ). Little is known of the cellular and molecular mechanisms that regulate sperm storage in and release from the SST.

Apical blebs on sperm storage tubule epithelial cell microvilli: their release and interaction with resident sperm in the turkey hen oviduct.

Located at the anterior end of the turkey hen's vagina are numerous discrete tubular invaginations of the surface epithelium, collectively referred to as the sperm storage tubules (SSTs). After mating or artificial insemination, sperm ascend the vagina, enter the SSTs, and over the ensuing days and weeks, gradually exit the SSTs and are transported to the anterior end of the oviduct to fertilize a daily succession of ova. Little is known regarding the cellular and molecular mechanisms responsible for sperm subsistence in the lumen of the SST.

Short periods of incubation during egg storage increase hatchability and chick quality in long-stored broiler eggs.

It is recognized that cool egg storage for 8 d or longer, commonly employed in broiler parent and commercial layer production, reduces hatchability. In this study, we investigated the efficacy of short periods of incubation during egg storage (SPIDES) in the restoration of hatchability of broiler hatching eggs stored for 21 d. Prolonged cool storage reduced hatchability of untreated eggs from 92 to 71%.

Expression of the chicken GDNF family receptor α-1 as a marker of spermatogonial stem cells.

The identification, enrichment and subsequent isolation of spermatogonial stem cells (SSCs) are integral to the success of SCC transplants between fertile donor and sterilized recipient males. In birds generally and particularly in chicken, SSC-specific has yet to be identified. The receptor for glial cell-derived neurotrophic factor (GDNF), i.

Comparison of blastoderm traits from 2 lines of broilers before and after egg storage and incubation.

We examined the impact of egg storage on the hatchability of eggs from 2 lines (A and B) of commercial broiler breeders with known differences in fertility (line B slightly higher) and hatchability following egg storage (line A slightly lower). Eggs from both lines were stored in a 16°C room for 3 to 4, 10 to 12, and 17 d, the blastoderms were isolated, evaluated, and statistically compared. No significant interactions (line × duration of storage) were observed in the following traits: blastoderm diameter, total and percentage of viable blastodermal cells, stage of blastoderm development, and embryo weight and stage of development after 7 d of incubation.

Oviductal expression of avidin, avidin-related protein-2, and progesterone receptor in turkey hens in relation to sperm storage: effects of oviduct tissue type, sperm presence, and turkey line.

The sperm storage tubules (SST) of the turkey hen, which are located in the uterovaginal junction (UVJ) of the oviduct, maintain viable sperm for up to 10 wk after a single insemination. The mechanisms of this in vivo sperm storage are poorly understood. Our objective was to evaluate mRNA and protein expression of avidin and 2 avidin-associated factors, avidin-related protein-2 (AVR2) and progesterone receptor, in the oviducts of 2 different lines to determine the extent to which they were sperm responsive and tissue specific.

Physiology and endocrinology symposium: role of the oviduct in maintaining sustained fertility in hens.

In poultry, sperm transferred by natural mating or AI into the distal end of the vagina immediately begin their ascent to the uterovaginal junction (UVJ) at the anterior end of the vagina. However, due to an intense selection process in the vagina, less than 1% of the sperm transferred actually reach the UVJ. Those sperm that do reach the UVJ enter numerous tubular invaginations of the surface epithelium of the vagina located in the UVJ mucosa, collectively referred to as the sperm-storage tubules (SST).

Restoration of spermatogenesis after transplantation of c-Kit positive testicular cells in the fowl.

Transplantation of male germ line cells into sterilized recipients has been used in mammals for conventional breeding as well as for transgenesis. We have previously adapted this approach for the domestic chicken and we present now an improvement of the germ cell transplantation technique by using an enriched subpopulation of c-Kit-positive spermatogonia as donor cells. Dispersed c-Kit positive testicular cells from 16 to 17 week-old pubertal donors were transplanted by injection directly into the testes of recipient males sterilized by repeated gamma irradiation.

Comparisons of sperm storage tubule distribution and number in 4 strains of mature broiler breeders and in turkey hens before and after the onset of photostimulation.

The biological basis of sustained fertility in broiler and turkey hens is their capacity to store sperm in the oviductal sperm storage tubules (SST) located in the uterovaginal junction. The objectives of this study were to determine if the numbers of SST varied between 4 strains of broiler breeders and determine the number of SST in the turkey before (less than 9 d of photostimulation) and after (up to 22 d of photostimulation and laying) photostimulation. No statistical differences were observed in SST numbers in the 4 strains of broilers examined or in turkey hens before and after the onset of egg production.

Morphology of the turkey vagina with and without an egg mass in the uterus.

In this study we examined the gross anatomy of the uterus and vagina in turkeys in egg production. With no uterine egg mass, removal of the tunica serosa that enclosed the uterus revealed deep periodic in-folding of the muscularis transversely circumscribing the sac-like segment. When the connective tissue embracing the neutral buffered formalin fixed vagina was completely teased free, the exposed tubular segment was shaped as a counter-clockwise spiral or as a series of angular, random bends.

Identification of various testicular cell populations in pubertal and adult cockerels.

Precise identification of the male germinal stem cell population is important for their practical use in programs dedicated to the integration of exogenous genetic material in testicular tissues. In the present study, our aim was to identify germinal cell populations in the testes of pubertal and adult cockerels based on the detection of the nuclear DNA content by fluorescence-activated cell sorting (FACS) and on the expression of the Dazl and Stra8 genes in single-cell suspensions of testicular tissues. Cells with a tetraploid DNA content (4c) represent a small and equal fraction of the total germinal cell population in both pubertal and adult males.

Turkey sperm reside in the tubular glands in the urodeum following artificial insemination.

A turkey hen in egg production requires 48 h after the last insemination to maximize the number of sperm in the uterovaginal junction sperm-storage tubules. Where the sperm that continue to fill the oviductal sperm-storage sites during this 48-h period reside remains unknown. Histological sections of the juncture of the vagina with the urodeum, the central compartment of the cloaca, revealed deep tubular glands containing periodic acid-Schiff-positive secretory material.

Serotonin localization in the turkey vaginal but not sperm storage tubule epithelia.

Elucidating the cellular and molecular mechanisms regulating sperm selection and transport in the vagina of the hen had been the focus of a limited amount of research over the past decade. New observations indicate the presence of nonneuron endocrine cells in the epithelia lining the lumina of the turkey hen vagina and uterovaginal junction. Although no cells in the vagina or uterovaginal junction surface epithelia exhibited argentaffin staining, typical of cells containing neurosecretory granules, cells restricted to the vaginal and uterovaginal junction but not the sperm storage tubule epithelia were immunoreactive positive to serotonin.

Alkaline phosphatase reactivity in the vagina and uterovaginal junction sperm-storage tubules of turkeys in egg production: implications for sperm storage.

1. Currently there remains contradictory information on the localisation and possible role of alkaline phosphatase (AP) in the chicken and Japanese quail oviducts. 2.

Restoration of spermatogenesis and male fertility by transplantation of dispersed testicular cells in the chicken.

Transplantation of male germ cells into sterilized recipients has been widely used in mammals for conventional breeding and transgenesis purposes. This study presents a workable approach for germ cell transplantation between male chickens. Testicular cells from adult and prepubertal donors were dispersed and transplanted by injection directly into the testes of recipient males sterilized by repeated gamma irradiation.

Morphological and histochemical characterization of the seminiferous epithelial and Leydig cells of the turkey.

Unlike mammals, there is little fundamental information about spermatogenesis in birds. This study was undertaken to clarify the morphology, histochemistry, and lectin affinity of the seminiferous epithelial cells and Leydig cells in pre-pubertal (8- to 15-week old) and adult (40- to 44-week old) domestic turkeys. In adult turkeys, three types of spermatogonia were defined based on their chromatin distribution and nuclear morphology: the dark type A (A(d)); the pale type A (A(p)); and the type B.

Effect of various photoperiods on testicular weight, weekly sperm output and plasma levels of LH and testosterone over the reproductive season in male turkeys.

The effects of duration and variation in photoperiod on testis weight, testicular sperm production, semen output, and hormone status over the reproductive season in male turkeys were investigated. In Experiment 1, four groups of males raised from 17 to 23 wk of age under a constant short photoperiod were subjected to a constant short (Group 1: 7L:17D; Group 2: 10.5L:13.

Spermatogenesis in the turkey (Meleagris gallopavo): quantitative approach in immature and adult males subjected to various photoperiods.

The objectives of this study were to identify and quantitate the germ cell populations of the testes in sexually mature male turkeys (Trial 1), determine the duration of meiosis based on BrdU labeling and stereological analyses (Trial 2), and examine the impact of various photoperiods on germinal and somatic cell populations in immature and adult males (Trial 3). In Trial 1, both testes within a male had similar stereological components (P>0.05) for all parameters analyzed.