The Effect of Short- and Long-Term Cryopreservation on Chicken Primordial Germ Cells.

Primordial germ cells (PGCs) are the precursors of functional gametes and the only cell type capable of transmitting genetic and epigenetic information from generation to generation. These cells offer valuable starting material for cell-based genetic engineering and genetic preservation, as well as epigenetic studies. While chicken PGCs have demonstrated resilience in maintaining their germness characteristics during both culturing and cryopreservation, their handling remains a complex challenge requiring further refinement. Herein, the study aimed to compare the effects of different conditions (freezing-thawing and in vitro cultivation) on the expression of PGC-specific marker genes. Embryonic blood containing circulating PGCs was isolated from purebred Green-legged Partridgelike chicken embryos at 14-16 Hamburger-Hamilton (HH) embryonic development stage. The blood was pooled separately for males and females following sex determination. The conditions applied to the blood containing PGCs were as follows: (1) fresh isolation; (2) cryopreservation for a short term (2 days); and (3) in vitro culture (3 months) with long-term cryopreservation of purified PGCs (~2 years). To characterize PGCs, RNA isolation was carried out, followed by quantitative reverse transcription polymerase chain reaction (RT-qPCR) to assess the expression levels of specific germ cell markers (SSEA1, CVH, and DAZL), as well as pluripotency markers (OCT4 and NANOG). The investigated genes exhibited consistent expression among PGCs maintained under diverse conditions, with no discernible differences observed between males and females. Notably, the analyzed markers demonstrated higher expression levels in PGCs when subjected to freezing than in their freshly isolated counterparts.

Influence of a Commercial Synbiotic Administered In Ovo and In-Water on Broiler Chicken Performance and Meat Quality.

The present study aimed to test the synbiotic PoultryStar® solUS delivered in ovo to evaluate its effect on hatchability, productive performance and meat quality, compared to its post-hatch administration in water. On the twelfth day of embryonic incubation, 1200 fertile eggs were divided into synbiotic groups injected with 2 mg/embryo (T1) and 3 mg/embryo (T2), a saline group injected with physiological saline and an uninjected control group (C). After hatching, 120 male chicks/group were reared and chicks from the saline group were supplemented with the synbiotic via drinking water (T3). Hatchability was low in both T1 and T2 groups. Growth performance was not affected by the treatments. However, in the second rearing phase (15-36 days), birds from the C and T3 groups were heavier than T1 birds, due to a higher feed intake and daily weight gain. Neither route of synbiotic administration influenced final body weight (at 56 days), weight and yield of the carcass or commercial cuts. Physico-chemical properties, total lipid, cholesterol and fatty acid composition of breast muscle were not affected by the treatments. Considering its exploratory nature, this study has raised many questions that need further investigation, such as the bioactive combination and the effect on embryonic development.

Proteome changes upon in ovo stimulation with Lactobacillus synbiotic in chicken liver.

The liver, as the main metabolic organ, plays a key role in many vital processes, including nutrient metabolism, fat digestion, blood protein synthesis, and endocrine management. As one of the immune organs, it has a remarkable ability to adequately activate the immune cells in response to metabolic signals. The anatomy of the liver ensures its close interaction with the gut so that nutrients and gut microbiota contribute to normal metabolism. In chickens, the intestinal microbiota plays an important role in supporting health and improving production parameters. The most effective method of stimulating the microbiota is to administer an appropriate bioactive compound during embryonic development. In ovo stimulation on d 12 of egg incubation involves the delivery of the substance into the air chamber. The aim of the study was to analyze the changes at the protein level after in ovo administration of the synbiotic on d 12 of egg incubation. Our study is the first to conduct a proteome analysis in liver after the administration of a Lactobacillus synbiotic in ovo. Eggs of broiler chickens were injected with a synbiotic-Lactobacillus plantarum with raffinose family oligosaccharides (RFO). On d 21 posthatching liver was collected. We performed analyses based on two-dimensional electrophoresis, matrix-assisted laser desorption/ionization (MALDI) time-of-flight, and MALDI Fourier-transform ion cyclotron resonance to obtain a global view of the hepatic proteome changes in response to in ovo injection. A representative pattern of significantly altered liver proteins was observed after stimulation with the synbiotic. A total of 16 protein spots were differentially expressed, with 5 downregulated and 11 upregulated spots. We conclude that the in ovo synbiotic treatment had the potential to accelerate the major energy-yielding metabolic pathways in the liver of adult broilers.

Comparison of the Transcriptomic and Epigenetic Profiles of Gonadal Primordial Germ Cells of White Leghorn and Green-Legged Partridgelike Chicken Embryos.

The Green-legged Partridgelike fowl is a native, dual-purpose Polish chicken. The White Leghorn has been intensively selected for several decades to mainly improve reproductive traits. Primordial germ cells (PGCs) represent the germline stem cells in chickens and are the only cells that can transfer the information stored in the genetic material from generation to generation. The aim of the study was to carry out a transcriptomic and an epigenetic comparison of the White Leghorn and Green-legged Partridgelike gonadal PGCs (gPGCs) at three developmental stages: days 4.5, 8, and 12 of the embryonic development. RNA and DNA were isolated from collected gPGCs. The RNA was further subjected to microarray analysis. An epigenetic analysis was performed based on the global methylation analysis and qMSP method for the particular silenced genes demonstrated in transcriptomic analysis. Statistically significant differences between the gPGCs from both breeds were detected on the day 8 of embryonic development. Global methylation analysis showed significant changes at the methylation level in the White Leghorn gPGCs on day 8 of embryonic development. The results suggest faster development of Green-legged Partridgelike embryos as compared to White Leghorn embryos. Changes in the levels of gene expression during embryonic development are determined by genetic and environmental factors, and this variability is influenced by breed and gender.

Chicken embryo as a model in epigenetic research.

Epigenetics is defined as the study of changes in gene function that are mitotically or meiotically heritable and do not lead to a change in DNA sequence. Epigenetic modifications are important mechanisms that fine tune the expression of genes in response to extracellular signals and environmental changes. In vertebrates, crucial epigenetic reprogramming events occur during early embryogenesis and germ cell development. Chicken embryo, which develops external to the mother's body, can be easily manipulated in vivo and in vitro, and hence, it is an excellent model for performing epigenetic studies. Environmental factors such as temperature can affect the development of an embryo into the phenotype of an adult. A better understanding of the environmental impact on embryo development can be achieved by analyzing the direct effects of epigenetic modifications as well as their molecular background and their intergenerational and transgenerational inheritance. In this overview, the current possibility of epigenetic changes during chicken embryonic development and their effects on long-term postembryonic development are discussed.

Effects of Selected Prebiotics or Synbiotics Administered in ovo on Lymphocyte Subsets in Bursa of the Fabricius, Thymus, and Spleen in Non-Immunized and Immunized Chicken Broilers.

The effects of in ovo-delivered prebiotics and synbiotics on the lymphocyte subsets of the lymphoid organs in non-immunized 7-day-old broiler chickens and in non-immunized, sheep red blood cells (SRBC)-immunized, and dextran (DEX)-immunized 21- and 35-day-old birds were studied. The substances were injected on the 12th day of egg incubation: Prebiotic1 group (Pre1) with a solution of inulin, Prebiotic2 group (Pre2) with a solution of Bi2tos (non-digestive transgalacto-oligosaccharides), Synbiotic1 group (Syn1) with inulin and Lactococcus lactis subsp. lactis IBB SL1, and Synbiotic2 group (Syn2) with Bi2tos and Lactococcus lactis subsp. cremoris IBB SC1. In 7-day-old chicks, a decrease in T splenocytes was noticed in all groups. The most pronounced effect in 21- and 35-day-old birds was an increase in TCRγδ+ cells in Syn1 and Syn2 groups. A decrease in bursal B cells was observed in DEX-immunized Pre1 group (21-day-old birds), and in the Syn1 group in non-immunized and SRBC-immunized 35-day-old birds. An increase in double-positive lymphocytes was observed in Pre1 (35-day-old birds) and Pre2 (immunized 21-day-old birds) groups. In Pre1 and Syn1 groups (21- and 35-day-old), an increase in B splenocytes and a decrease in T splenocytes were observed. We concluded that Syn1 was the most effective in the stimulation of the chicken immune system.

Concentration and total number of circulating primordial germ cells in Green-legged Partridgelike chicken embryos.

The Green-legged Partridgelike fowl is an old Polish indigenous breed of chicken. Primordial germ cells (PGCs) are one of the best sources of precursor cells that can be used for the conservation and proliferation of the endangered breeds of bird. Initially, the chicken PGCs colonize at the anterior extraembryonic region called "germinal crescent," and after the establishment of blood vascular circulation, they temporally circulate via the embryonic blood vascular system along with embryonic blood cells. They further colonize at the microcapillary networks of both right and left future gonadal regions. Subsequently, they migrate interstitially to reach gonadal anlages, where they begin to differentiate and eventually develop into the future ova or sperm. The basic knowledge regarding the concentration and the total number of circulating PGCs (cPGCs) throughout their circulating phase in the early embryonic stages is crucial for providing an insight into the mechanisms by which they circulate and colonize at the capillary networks of left and right future gonadal regions in each developmental stage. The present study aims to determine the most efficient developmental stage that is suitable to collect cPGCs. The concentration of cPGCs was directly measured, and total volume of embryonic blood was calculated based on the concentration of PKH26-stained embryonic blood cells which were injected 10 min before the blood sampling process in the same embryo during each stage of embryonic development from stage 13 Hamburger and Hamilton (HH; Hamburger and Hamilton, 1951) to 16 HH. Analysis of whole embryonic bloodstream revealed that at stage 14 HH of embryonic development, peak total number of cPGCs (386.3 cells/µL) and peak concentration of cPGCs (18.6 cells/µL) were observed. Later, there was a decrease in concentration, suggesting that the cPGCs might be trapped gradually by the capillary networks at the future gonadal regions after stage 15 HH.

In Vitro Culture of Chicken Circulating and Gonadal Primordial Germ Cells on a Somatic Feeder Layer of Avian Origin.

The present study had two aims: (1) To develop a culture system that imitates a normal physiological environment of primordial germ cells (PGCs). There are two types of PGCs in chicken: Circulating blood (cPGCs) and gonadal (gPGCs). The culture condition must support the proliferation of both cPGCs and gPGCs, without affecting their migratory properties and must be deprived of xenobiotic factors, and (2) to propose an easy-to-train, nonlabeling optical technique for the routine identification of live PGCs. To address the first aim, early chicken embryo's feeder cells were examined instead of using feeder cells from mammalian species. The KAv-1 medium at pH 8.0 with the addition of bFGF (basic fibroblast growth factor) was used instead of a conventional culture medium (pH approximately 7.2). Both cPGCs and gPGCs proliferated in vitro and retained their migratory ability after 2 weeks of culture. The cultivated cPGCs and gPGCs colonized the right and/or left gonads of the recipient male and female embryos. To address the second aim, we demonstrated a simple and rapid method to identify live PGCs as bright cells under darkfield illumination. The PGCs rich in lipid droplets in their cytoplasm highly contrasted with the co-cultured feeder layer and other cell populations in the culture.

Dynamics of the transcriptome during chicken embryo development based on primordial germ cells.

OBJECTIVE: Regulation of gene expression during embryo development on the basis of migration of primordial germ cells (PGCs) in vivo has been rarely studied due to limited cell number and the necessity to isolate PGCs from a large number of embryos. Moreover, little is known about the comprehensive dynamics of the transcriptome in chicken PGCs during early developmental stages. The current study investigated transcriptome dynamics of chicken PGCs at key developmental stages: 4.5, 8 and 12 days of embryo incubation. PGCs were collected, and RNA was isolated using a commercial kit for single cells. The isolated RNA was subjected to microarray analysis (Agilent Technologies). RESULTS: Between 8 and 12 days of incubation, the highest number of genes was regulated. These data indicate that the most intense biological activity occurs between 8 and 12 days of embryo development. Heat map showed a significant decrease in gene expression on day 8, while it increased on day 12. The development of a precise method to isolate bird PGCs as well as the method to isolate RNA from single cells isolated from one embryo allows for early molecular analysis and detection of transcriptome changes during embryonic development.

Metabolic Gene Expression in the Muscle and Blood Parameters of Broiler Chickens Stimulated In Ovo with Synbiotics.

To better understand the effects of synbiotics administered at early stages of embryonic development in poultry, it is necessary to analyze direct effects (meat quality) and the molecular background. The molecular interpretation of poultry meat properties after in ovo administration of synbiotics remains to be reported. The purpose of the present study was to analyze the molecular background of meat quality based on gene expression and basic physiological parameters. Eggs were injected with (S1) Lactobacillus salivarius with galacto-oligosaccharides or (S2) Lactobacillus plantarum with raffinose family oligosaccharides. The pectoral muscle was collected at two time points (day 7 and day 42) and subjected to RNA isolation. Gene expression analysis was performed by RT-qPCR for a panel of eight genes associated with metabolism. The concentration of glucose and hormones (insulin, glucagon, and leptin (S1 p = 0.04)) was also increased. The obtained results showed that metabolic gene expression in the muscle was more differential due to synbiotic stimulation on day 7 (FST in S1 p = 0.03; PDK4 in S1 p = 0.02 and S2 p = 0.01; CEBPB in S1 p = 0.01 and S2 p = 0.008; PHKB in S1 p = 0.01; PRKAG3 in S1 p = 0.02) than on day 42 (PDK4 in S1 p = 0.04). On the basis of the results obtained, it can be concluded that in ovo stimulation with S1 triggered the most potent and favorable changes in the pectoral muscle gene expression in broiler chickens.

Impact of Prebiotics and Synbiotics Administered in ovo on the Immune Response against Experimental Antigens in Chicken Broilers.

The effect of the in ovo application of selected prebiotics and synbiotics on the humoral immune response against T-dependent (SRBC) and T-independent (dextran) antigens and delayed-type hypersensitivity (DTH) to phytohemagglutinin was studied. On the 12th day of incubation, 800 eggs (Ross 308) were divided into five groups and injected into the egg air chamber with prebiotic inulin (Pre1), Bi2tos (Pre2), a synbiotic composed of inulin and Lactococcus lactis subsp. lactis IBB SL1 (Syn1), a synbiotic composed of Bi2tos and L. lactis subsp. cremoris IBB SC1 (Syn2), and physiological saline (control group; C). The chickens were immunized twice at the 7th and 21st day of life with SRBC and dextran. A DTH test was performed on the 7th, 21st, and 35th day. The application of prebiotics and synbiotics had no significant effect on the humoral immune response. SRBC-immunized in ovo Pre1- and Pre2-treated chickens showed significantly higher serum IgG levels than the control. A significant effect on the DTH reaction was detected on the 7th (Pre1 < C) and 21st (Pre2 > Syn2) day. However; Bi2tos may transiently stimulate the cellular immune response on the 21st day. It may be concluded that the application of inulin in an egg air chamber on the 12th day of incubation may stimulate the secondary immune response. The inulin-treated group exhibited a lower mortality rate than the control group.

Injection of Raffinose Family Oligosaccharides at 12 Days of Egg Incubation Modulates the Gut Development and Resistance to Opportunistic Pathogens in Broiler Chickens.

The aim was to investigate the impact of an automatic in ovo injection of the raffinose family oligosaccharides (RFO) extracted from the seeds of Lupinus luteus L, on the chicken performance and resistance in a production environment. At day 12 of incubation, a total of 57,900 eggs (Ross 308) were divided into two groups: 1/ Control, injected with 0.9% NaCl and 2/ RFO group, injected with 1.9 mg/egg of the lupin seed extract, dissolved in 0.2 mL NaCl. The performance parameters, biochemical indices (lipid profile, hepatic parameters), gut histomorphology and duodenum structure, oxidative stability of the meat and microbiological counts of the major commensal microbiota species were analyzed. Mortality, body weight, and feed conversion ratio (FCR) were not affected. By day 42, several health indices were improved with RFO and were reflected in a beneficial lipid blood profile, increased villi surface and better combating opportunistic pathogens through reduction of Clostridia and decreased coccidia counts. The RFO increased meat oxidation, but only at the beginning of the storage. The RFO sourced from local legumes can be considered a promising prebiotic for broiler chickens. In ovo delivery of prebiotics and/or synbiotics should be further optimized as an important strategy for the earliest possible modulation of chicken resistance.

Molecular Response in Intestinal and Immune Tissues to in Ovo Administration of Inulin and the Combination of Inulin and Lactobacillus lactis Subsp. cremoris.

Intestinal microbiota are a key factor in maintaining good health and production results in chickens. They play an important role in the stimulation of immune responses, as well as in metabolic processes and nutrient digestion. Bioactive substances such as prebiotics, probiotics, or a combination of the two (synbiotic) can effectively stimulate intestinal microbiota and therefore replace antibiotic growth promoters. Intestinal microbiota might be stimulated at the early stage of embryo development in ovo. The aim of the study was to analyze the expression of genes related to energy metabolism and immune response after the administration of inulin and a synbiotic, in which lactic acid bacteria were combined with inulin in the intestines and immune tissues of chicken broilers. The experiment was performed on male broiler chickens. Eggs were incubated for 21 days in a commercial hatchery. On day 12 of egg incubation, inulin as a prebiotic and inulin with Lactobacillus lactis subsp. cremoris as a synbiotic were delivered to the egg chamber. The control group was injected with physiological saline. On day 35 post-hatching, birds from each group were randomly selected and sacrificed. Tissues (spleen, cecal tonsils, and large intestine) were collected and intended for RNA isolation. The gene panel (ABCG8, HNF4A, ACOX2, APBB1IP, BRSK2, APOA1, and IRS2) was selected based on the microarray dataset and biological functions of genes related to the energy metabolism and immune responses. Isolated RNA was analyzed using the RT-qPCR method, and the relative gene expression was calculated. In our experiment, distinct effects of prebiotics and synbiotics following in ovo delivery were manifested in all analyzed tissues, with the lowest number of genes with altered expression shown in the large intestines of broilers. The results demonstrated that prebiotics or synbiotics provide a potent stimulation of gene expression in the spleen and cecal tonsils of broiler chickens. The overall number of gene expression levels and the magnitude of their changes in the spleen and cecal tonsils were higher in the group of synbiotic chickens compared to the prebiotic group.

Microstructure of the small intestine in broiler chickens fed a diet with probiotic or synbiotic supplementation.

The aim of the study was to determine the effect of dietary supplementation of a probiotic and a synbiotic on the morphometric parameters of the small intestine of broiler chickens. The experiment was conducted on three hundred sixty, one-day-old female Ross 308 chicks, which were randomly selected from 20,000 birds and divided into three treatment groups (n = 120) with ten replicates per treatment. The control group (C) was fed a commercial diet, the probiotic group (PRO) was fed the same diet with an added 1% of the probiotic Lavipan® (Lactococcus lactis, Carnobacterium divergens, Lactobacillus casei, Lactobacillus plantarum and Saccharomyces cerevisiae), and the synbiotic group (SYN) was fed the commercial diet with an added synbiotic: 0.8% of the prebiotic RFO (extracted from lupin seeds) and 1% Lavipan®. According to the manufacturer's data, apart from the typical probiotic action,microorganisms contained in the preparation release anti-bacterial substances (hydrogen peroxide and bacteriocins) and, therefore, are antagonistic towards pathogenic bacteria present in the gut of animals. Supplementation took place in the first seven days of rearing, and all birds had ad libitum access to water and feed during the 42 days of the experiment. On the last day, all birds were slaughtered and samples from three segments of the small intestine were taken. Villi area, height, width and crypt depth ratios were read using Multiscan software. Synbiotic supplementation increased the BWG of broilers from first to tenth day of rearing, compared to the control group. The PRO group had improved villi morphometric parameters of the duodenum. In the jejunum and ileum, both bioactive substances improved villus width and villus surface area. Crypts were deeper in the small intestine of birds supplemented with bioactive substances, which allows greater renewal of the villi. As expected, the intestinal morphometric parameters of broiler chickens benefited from bioactive substance supplementation.

Selected prebiotics and synbiotics administered in ovo can modify innate immunity in chicken broilers.

BACKGROUND: A previous study showed that prebiotics and synbiotics administered in ovo into the egg air cell on the 12th day of incubation enhance the growth and development of chickens. However, the influence of this procedure on the development and efficiency of the innate immune system of broiler chickens is unclear. Therefore, the aim of this study was to evaluate whether the early (on the 12th day of embryo development) in ovo administration of selected prebiotics (inulin - Pre1 and Bi2tos - Pre2) and synbiotics (inulin + Lactococcus lactis subsp. lactis IBB SL1 - Syn1 and Bi2tos + L. lactis subsp. cremoris IBB SC1 - Syn2) influences the innate immune system. RESULTS: Chickens (broiler, Ross 308) that were treated with Pre1 exhibited a decreased H/L ratio on D7, but an increased H/L ratio was observed on D21 and D35. In the remaining experimental groups, an increase in the H/L ratio was observed on D21 and D35. The oxidative potential of leukocytes measured using the NBT test increased on D21 in Pre2 and Syn1 groups. The rate of the phagocytic ability of leukocytes increased in Pre1 and Syn1 groups on D21. The phagocytic index decreased in Pre1 and Syn2 groups on D21 and D35. Concurrently, the count of WBC in circulating blood decreased on D21 in Pre1, Pre2, and Syn1 groups. The hematocrit value was increased in Syn1 chickens on D21, in Pre1 chickens on D35, and in Syn2 chickens on both time points. CONCLUSIONS: Early in ovo treatment of chicken embryos with prebiotics and synbiotics may temporarily modulate not only the production/maturation of leukocytes but also their reactivity.

Yucca schidigera can mitigate ammonia emissions from manure and promote poultry health and production.

Mojave yucca (Yucca schidigera) is widely grown in the deserts. This herb is commercially used because it is rich in saponins and phenolic compounds with antioxidant effect. Y. schidigera or its derivatives are included as nontoxic food supplements, in cosmetics, and in the pharmaceutical industry. Saponins originated from Y. schidigera have anti-inflammatory, antioxidant, immunostimulatory, growth promoter, hypocholesterolemic, and hypoglycemic effects. To date, the key role of Y. schidigera or its products in animal nutrition is to reduce the ammonia content in the atmosphere and fecal odor in poultry excreta. Mitigating ammonia by using this plant could be achieved by the modification of gut microbiota, enhancement in digestion, and absorption of nutrients, leading to a better growth and production performance of animals and poultry. Various methods were applied to mitigate the emission of odor from the litter by different strategies including biofilters, litter treatments, air scrubbers, neutralizing agents, windbreak walls, etc., but these techniques are expensive. This article provides a new insight to scientists and poultry breeders to use Y. schidigera plant or its products as inexpensive and safe sources of a feed supplement to overcome the ammonia and fecal odor problems, as well as reduce environmental pollution in poultry houses.

Molecular signatures of epithelial oviduct cells of a laying hen (Gallus gallus domesticus) and quail (Coturnix japonica).

BACKGROUND: In this work we have determined molecular signatures of oviduct epithelial and progenitor cells. We have proposed a panel of selected marker genes, which correspond with the phenotype of oviduct cells of a laying hen (Gallus gallus domesticus) and quail (Coturnix japonica). We demonstrated differences in characteristics of those cells, in tissue and in vitro, with respect to different anatomical and functional parts of the oviduct (infundibulum (INF), distal magnum (DM, and proximal magnum (PM)). The following gene expression signatures were studied: (1) oviduct markers (estrogen receptor 1, ovalbumin, and SPINK7 - ovomucoid), (2) epithelial markers (keratin 5, keratin 14, and occludin) and (3) stem-like/progenitor markers (CD44 glycoprotein, LGR5, Musashi-1, and sex determining region Y-box 9, Nanog homebox, OCT4/cPOUV gene encoding transcription factor POU5F3). RESULTS: In chicken, the expression of oviduct markers increased toward the proximal oviduct. Epithelial markers keratin14 and occludin were high in distal oviduct and decreased toward the proximal magnum. In quail oviduct tissue, the gene expression pattern of oviduct/epithelial markers was similar to chicken. The markers of progenitors/stemness in hen oviduct (Musashi-1 and CD44 glycoprotein) had the highest relative expression in the infundibulum and decreased toward the proximal magnum. In quail, we found significant expression of four progenitor markers (LGR5 gene, SRY sex determining region Y-box 9, OCT4/cPOUV gene, and CD44 glycoprotein) that were largely present in the distal oviduct. After in vitro culture of oviduct cells, the gene expression pattern has changed. High secretive potential of magnum-derived cells diminished by using decreased abundance of mRNA. On the other hand, chicken oviduct cells originating from the infundibulum gained ability to express OVM and OVAL. Epithelial character of the cells was maintained in vitro. Among progenitor markers, both hen and quail cells expressed high level of SOX9, LGR5 and Musashi-1. CONCLUSION: Analysis of tissue material revealed gradual increase/decrease pattern in majority of the oviduct markers in both species. This pattern changed after the oviductal cells have been cultured in vitro. The results can provide molecular tools to validate the phenotype of in vitro biological models from reproductive tissue.

GLP1 and GIP are involved in the action of synbiotics in broiler chickens.

BACKGROUND: In order to discover new strategies to replace antibiotics in the post-antibiotic era in meat-type chicken production, two new synbiotics were tested: (Lactobacillus salivarius IBB3154 plus galactooligosaccharide (Syn1) and Lactobacillus plantarum IBB3036 plus raffinose family oligosaccharides (Syn2). METHODS: The synbiotics were administered via syringe, using a special automatic system, into the egg air chamber of Cobb 500 broiler chicks on the 12th day of egg incubation (2 mg of prebiotics + 105 cfu bacteria per egg). Hatched roosters (total 2,400) were reared on an experimental farm, kept in pens (75 animals per pen), with free access to feed and water. After 42 d animals were slaughtered. Blood serum, pancreas, duodenum and duodenum content were collected. RESULTS: Syn2 increased trypsin activity by 2.5-fold in the pancreas and 1.5-fold in the duodenal content. In the duodenum content, Syn2 resulted in ca 30% elevation in lipase activity and 70% reduction in amylase activity. Syn1 and Syn2 strongly decreased expression of mRNA for GLP-1 and GIP in the duodenum and for GLP-1 receptors in the pancreas. Simultaneously, concentrations of the incretins significantly diminished in the blood serum (P < 0.05). The decreased expression of incretins coincides with changed activity of digestive enzymes in the pancreas and in the duodenal content. The results indicate that incretins are involved in the action of Syn1 and Syn2 or that they may even be their target. No changes were observed in key hormones regulating metabolism (insulin, glucagon, corticosterone, thyroid hormones, and leptin) or in metabolic indices (glucose, NEFA, triglycerides, cholesterol). Additionally, synbiotics did not cause significant changes in the activities of alanine and aspartate aminotransferases in broiler chickens. Simultaneously, the activity of alkaline phosphatase and gamma glutamyl transferase diminished after Syn2 and Syn1, respectively. CONCLUSION: The selected synbiotics may be used as in ovo additives for broiler chickens, and Syn2 seems to improve their potential digestive proteolytic and lipolytic ability. Our results suggest that synbiotics can be directly or indirectly involved in incretin secretion and reception.

Generation of transgenic chickens by the non-viral, cell-based method: effectiveness of some elements of this strategy.

Transgenic chickens have, in general, been produced by two different procedures. The first procedure is based on viral transfection systems. The second procedure, the non-viral method, is based on genetically modified embryonic cells transferred directly into the recipient embryo. In this review, we analyzed the effectiveness of important elements of the non-viral, cell-based strategy of transgenic chicken production. The main elements of this strategy are: isolation and cultivation of donor embryonic cells; transgene construction; cell transfection in vitro; and chimera production: injection of cells into recipient embryos, raising and identification of germline chimeras, mating germline chimeras, transgene inheritance, and transgene expression. In this overview, recent progress and important limitations in the development of transgenic chickens are presented.