Conservation of avian genetic resources is important, as 13.0% (1,313/10,064) of known avian species are currently categorized as endangered by the International Union for Conservation of Nature and Natural Resources (IUCN, 2012). Development of an integrated system for conservation of avian genetics is necessary; however, germplasm conservation systems developed for mammals cannot be applied directly to avians, primarily due to the unique anatomical and physiological characteristics of the avian egg. Thus an alternative strategy for conservation of oviparous species of animals must be developed. Recent technological developments for producing germline chimeras by the transfer of primordial germ cells into recipient embryos has enabled the conservation and retrieval of chicken genetic resources in their complete form. Furthermore, the possibility of propagating endangered wild birds through interspecies germline chimeras has been proposed. In the present review, the current status of avian genetic resource conservation is presented with a focus on the following 4 topics: 1) semen cryopreservation, 2) germline chimeras, 3) somatic nuclear transfer, and 4) other related technologies.
Intestinal fatty acid binding protein (I-FABP) is involved in fatty acid transportation in mammals. To verify its role in fatty acid metabolism in birds, the model of pigeon intestinal organ culture was established, and a full-length cDNA of I-FABP was cloned from the intestine of Columba livia by rapid amplification of cDNA ends (RACE) method for the first time. The full length cDNA of C. livia I-FABP was 855 bp, including a 5′untranslated region (UTR) of 34 bp, a 3′UTR of 422 bp and an open reading frame (ORF) of 399 bp encoding a protein of 132 amino acids with the predicted molecular weight of 15.13 kDa. Sequence comparison indicated that I-FABP of C. livia had high identity with other avian I-FABP and belonged to the first subfamily of FABPs. Using quantitative real-time PCR, pigeon I-FABP mRNA in duodenum and jejunum increased progressively with development stage. I-FABP mRNA was expressed at the highest level at 28 day post hatch in the duodenum, while in ileum, it reached the maximum at the day of hatch, and decreased subsequently. The effects of fatty acids on pigeon I-FABP expression were also investigated in vitro. The results showed that significant increases in the pigeon I-FABP mRNA level were induced by linoleic acid and arachidonic acid, whereas I-FABP gene expression appeared to be unaffected by oleic acid and α-linolenic acid. The results indicate that I-FABP may be indicative of intestine development in pigeon, and it could be regulated by n-6 polyunsaturated fatty acids.
The aim of present study was to fit the best predictive equation to describe the growth curve of different Japanese quail lines. Moreover the effect of short-term divergent selection on the growth curve parameters was investigated. The quail lines utilized in the current study were two divergently selected lines for high (HW) and low (LW) 4-wk body weight (BW) and a control line (C). Determination and adjusted determination coefficients, relative error mean and standard deviation, mean square error, Akaike’s information criteria and Schwarz Bayesian information criteria were used to evaluate the accuracy of prediction with the growth functions of Hyperbolastic (H1, H2, H3), Richards, Gompertz, Logistic and Von bertalanffy. Based on model behavior and statistical performance, the Gompertz and Logistic functions were not able to show a suitable fit for all three lines. The overall goodness of fit statistics in the HW line showed that the Richards function has the best fit to the data followed by H3, H2, H1, Von bertalanffy, Gompertz and Logistic functions, respectively. The overall results in the LW and C lines were similar to the HW line, except that Logistic function provided a better fit to the data than Gompertz. The study of growth pattern using Richards function revealed that short-term divergent selection altered the growth trajectory of selected lines through the changing of shape parameters and relative intensity of growth rates.
The present study was designed to evaluate whether plum (Prunus mume Siebold and Zucc., PM) products affect growth performance, digestive enzymes, enteric microflora and inflammatory cytokines in growing broiler chicks. A total of one hundred twenty eight, 3-d-old broiler chicks were assigned to a basal diet (CON) and a basal diet supplemented with antibiotics (ANT), freeze-dried Prunus mume powder (PMP, 0.25%) and Prunus mume extract (PME, 0.125%) until 35 days of age. Throughout the entire feeding period (3-35 days), there were no differences in body weight, feed intake, total gain and feed to gain ratio among the birds fed the basal diet and those fed the diet supplemented with antibiotics, either PM powder or extract. The specific activities of pancreatic α-amylase and trypsin significantly increased (P<0.05) in birds fed the PME diet compared with those fed the CON and ANT diets. However, the specific activities of intestinal hydrolases such as maltase, sucrase and leucine aminopeptidase were not affected by the dietary groups. The colony forming units (CFU) of E. coli in the digesta of ileo-cecum in the PMP and PME groups were similar to those in the ANT group. The CFU of lactobacilli in the PMP and PME groups was significantly greater (P<0.05) than that in the ANT group, although there was no difference between the PMP and PME groups. The mRNA expression of splenic IL-1β and IL-6, pro-inflammatory cytokines, was significantly higher (P<0.05) in the PME group than in the CON group without affecting thymic cytokines. In summary, the dietary PM extract showed beneficial effects on pancreatic digestive enzymes, enteric microflora population and inflammatory cytokine mRNA expression, suggesting that PM extract might be a potential candidate as an alternative to antibiotics in birds.
Dibutoxybutane (DBB) is a possible growth promoter contained in shochu distillery by-product. In the present study, we synthesized DBB in order to confirm the growth promoting action. After determining the chemical structure of the synthetic product by nuclear magnetic resonance and gas chromatography mass spectrometry, an experiment was conducted using chicken skeletal muscle cells. DBB was mixed with the culture medium at the level of 0, 0.015, 0.15, 1.5, 15 and 150 μg/ml and cells derived from thigh muscle of 13-day-old chick embryos were raised for 6 days. The muscle cell growth was accelerated and the rate of protein degradation estimated from Nτ-methylhistidine release into the medium was decreased by DBB. Furthermore, the mRNAs of muscle-specific E3 ubiquitin ligases, atrogin-1/MAFbx and MuRF1, were decreased by DBB. However, mRNAs of ubiquitin, proteasome C2 subunit and μ-calpain were not affected by DBB. Activities of chicken’s two ubiquitous μ- and μ/m-calpain which were quantified by casein zymography were decreased by DBB. These results show that DBB promotes muscle growth due to a decrease in the rate of protein degradation.
The objective of this study was to determine the appropriate concentration of dietary supplementation of curcumin, and its effect on growth performance, intestinal morphology, fat metabolism and nutrients utilization of broiler chicks. Four hundred eighty, 1-day-old Arbor Acre broiler chicks were allocated into four groups with 6 replicates of 20 birds per cage. Birds were fed a corn-soybean basal diet supplemented with curcumin at 0 (control, CRM0), 100 (CRM100), 150 (CRM150) and 200 mg/kg (CRM200) levels for 42 days. All birds were kept in wire floor triple deck battery cages under semi-intensive housing management. The results revealed that dietary supplementation of curcumin at 200 mg/kg significantly improved live body weight and feed efficiency at marketing age (42 d); while, there was no significant difference on feed intake as compared to control. Curcumin significantly improved utilization of apparent metabolizable energy and decreased abdominal fat at 42 d in CRM150 and CRM200 broilers, respectively. Plasma T4 hormone level and fat utilization were significantly increased; while plasma cholesterol level was significantly reduced in dose dependent manner for CRM200 broilers. The results showed that dietary supplementation of curcumin influenced the histomorphological measurements of small intestinal villi. The villus height was significantly increased in duodenum, jejunum and ileum in curcumin supplemented broilers. Villus width was also significantly increased in duodenum and jejunum (42 d). While, there was no significant difference in ileum villus width. Furthermore, villus height to crypt depth ratio was significantly increased in all segments (except jejunum 42 d) of small intestine in CRM200 group; however, the intestinal crypt depth was lowered in curcumin supplemented broilers. In conclusion, supplementation of curcumin at 200 mg/kg feed enhanced the growth performance and fat metabolism, and increased villus absorptive area of small intestine, resulting in improved nutrients absorption in CRM200 group.
An experiment was conducted with 312 day-old male broiler chicks in grower phase (8-28d) to estimate the biological availability of four sources of zinc (Zn); zinc sulfate (ZnSO4·H2O), two sources of zinc oxide (ZnO FG1 and ZnO FG2) and Bioplex Zn. Zinc sulfate was used as the standard in the bioavailability assay. Chicks were allotted randomly to 13 dietary treatments with 6 birds per replicate and 4 replicates per treatment, that included an unsupplemented corn-soybean meal basal diet (25.50 mg of Zn/kg of DM), or the basal diet supplemented with 100, 150 or 200 mg/kg of DM as either ZnSO4·H2O (33% Zn), zinc oxide FG1 (72% Zn), zinc oxide FG2 (75% Zn) or Bioplex Zn (15% Zn). Dietary zinc level and source had no effect (P>0.05) on feed intake or body weight gain of chicks during first and second weeks of experimental periods, but feed conversion ratio in the first and second week and feed intake, body weight gain or feed conversion ratio in third week and total experimental periods were significant difference between treatments (P<0.05). Using the slope ratio methods from the regression of weight gain on supplemental zinc intake. The relative biological availability values using body weight gain were estimated to be 59, 99 or 45 for three levels of zinc oxide FG1, 64, 78 or 31 for three levels of zinc oxide FG2 and 151, 200 or 147 for three levels of Bioplex Zn, respectively. From the standpoint of bioavailability, Bioplex Zn was more available to broiler chicks than zinc from other sources and can be used by the feed industry as sources of supplemental zinc for broiler chickens.
An experiment was conducted in mixed sexes broiler chickens 1-d-old (Ross 308) to investigate the effects of 25-hydroxycholecalciferol (25-OH-D3) on growth performance parameters, immunity and bone calcification. A completely randomized design with 4 experimental diets was used: 1) diet with cholecalciferol (VIT-D3) at 200 IU/kg of feed (NRC-1994 level); 2) diet with 25-OH-D3 at 69 μg/kg of feed; 3) diet with VIT-D3 at 2000 IU/kg of feed (commercial level); and 4) as diet 3+25-OH-D3 at 69 μg/kg of feed. Experimental treatments consisted in 6 repetitions of 10 chickens each. On 21 d of trial, chickens fed diets with VIT-D3 at commercial level (with or without 25-OH-D3) increased the BWG (P<0.05) than those supplemented with VIT-D3 at NRC-1994 level or single 25-OH-D3. The feed conversion ratio of chickens was improved (P<0.01) by using diets supplemented with VIT-D3 at commercial level (with or without 25-OH-D3) than that diet with VIT-D3 at NRC-1994 level. Calcium content in tibias of broiler (21 d old) was increased (P<0.05) with the use of diets added 25-OH-D3＋VIT-D3 (commercial level) respect to those diets with VIT-D3 at NRC-1994 or commercial level. At 14 d, chickens fed diets with 25-OH-D3 increased (P<0.05) the delayed cutaneous hypersensitivity response than those fed only VIT-D3 (NRC-1994 or commercial levels). The antibody response against Newcastle disease vaccine was better (P<0.05) in chickens fed diets with commercial levels of VIT-D3(with or without 25-OH-D3) than those diets, VIT-D3 NRC-1994 level or single 25-OH-D3 supplementation. It can be concluded that higher levels of VIT-D3 (2000 IU/kg of feed) than those recommended by NRC (1994) improved the growth performance and the antibody response; and the supplementation of 25-OH-D3 at 69 μg/kg of feed increased the cellular immune response and the bone calcification of broiler chickens.
The present study was performed to measure activities of mucosal chitinase and N-acetyl-β-D-glucosaminidase (NAGase) in the proventriculus, duodenum jejunum and ileum of broilers given standard and shrimp meal (SM) diets. Activities of both enzymes were extremely high (P<0.05) in the proventriculus, and low or negligible in other parts, and in the proventriculus, activity of chitinase was much greater than that of NAGase. Dietary SM containing chitin had little or decreasing effect on activities of both enzymes. The result obtained here suggests that in broilers, chitin digestion by mucosal enzymes occurs mainly in the proventriculus, and the enzyme activities are not stimulated by dietary chitin.
The aim of this study was to determine whether T cells were recruited in the chicken seminal tract in response to lipopolysaccharide (LPS). The epididymis and ductus deferens were collected from matured roosters before and after 3 or 6 h of intravenous injection with 0.5 mg LPS per kg body-weight (LPS group) or phosphate buffered saline (control group). Their cryostat sections were immunostained using anti-chicken CD4 and CD8 antibodies. The frequencies of immunopositive cells in the rete testis, efferent duct and epididymal duct in the epididymis and ductus deferens were analyzed under a microscope with image analysis software. Both types of T cells were identified predominantly in the connective tissue underlying the mucosal epithelium and occasionally in the epithelium of the ducts in the epididymis and ductus deferens in all birds. Frequency of CD4+ T cell was increased in the ductus deferens 6 h post LPS injection. Their frequency in the efferent duct and ductus deferens was greater in the LPS group than in the control group after 6 h of injection. The frequency of CD8+ T cells in the LPS treated group was significantly increased in the efferent duct after 3 h and in the ductus deferens after 6 h of LPS injection. Significantly higher frequency of CD8+ T cells in the LPS group than in the control group was identified after 6 h of injection in the rete testis, efferent duct and ductus deferens. These results suggest that both CD4+ and CD8+ T cells are recruited in response to LPS stimulation in the rooster seminal tract, and the T cell-mediated local immune system is active in that organ.
In this study, whether the secretion of the uterine fluid (UF) exerts a role in the prolongation of functional life-span of the sperm in the hen oviduct was evaluated. The sperm were subjected to upper vaginal artificial insemination (AI) in the vicinity of the utero-vaginal junction (UVJ) under conditions of either non-secretion, plumping fluid (PF) secretion, or calcifying fluid (CF) secretion of the uterus of hens. Aliquots of the sperm were also subjected to in vitro storage at 41°C for 0, 2, 4, and 6 h in Lake’s solution (LS), PF and CF. Following AI, the exposure of the sperm to either PF or CF secretion resulted in a remarkably a longer duration of the fertile egg production compared to when the AI was performed during the non-secretory phase of the uterus (P<0.05). Similarly, the in vitro exposure of the sperm to PF and CF during storage resulted in increased survivability and penetrability of the sperm compared with storage in LS (P<0.05). In particular, distinct functional differences (P<0.05) were observed between the sperm stored in vivo and in vitro under PF and CF conditions. The sperm inseminated in the presence of PF secretion exhibited a longer period of fertile egg production, and the sperm stored in PF in vitro exhibited a higher capacity for survival and penetration into the inner perivitelline layer (IPL) than those inseminated in the presence of CF secretion or were stored in vitro in CF, respectively, indicating that exposure of the sperm to the UF might influence sperm function. In conclusion, the in vivo and in vitro findings suggest that the secretion of UF in the oviduct of hens may prolong sperm survival and maintain the fertility potential of the fowl sperm.
The aim of this study was to determine how the mucosal immunity mediated by T cells is developed in the vagina. Antigen-presenting cells and T cells play important roles in the early process of host defense. Mature T cells and immature dendritic cells expressing CC chemokine receptor (CCR) 6. In contrast, immature T cells and mature dendritic cells express CCR7. It was examined whether repeated antigen stimulation is effective for development of the pool of antigen-presenting cells and T cells in the vagina. White Leghorn hens were intravaginally injected 1 (single injection group) or 5 times (repeated injection group) in 10 days with saline (control) or lipopolysaccharide (LPS). The vagina was collected 1 day after the final injection. Frozen sections of them were immunostained for CD4+, CD8+, TCRγδ+ T cells and major histocompatibility complex (MHC) class II+ cells. Expressions of CCR6, CCR7 and MHC class II were analyzed by quantitative RT-PCR. The frequency of CD4+, CD8+, TCRγδ+ T cells were significantly increased in LPS-repeated injection group, however that of MHC class II+ cells was not changed significantly. The expression of CCR6 was significantly upregulated in LPS-repeated injection group, however, the expression of CCR7 and MHC class II was not affected. The densities of the each T cell subset and MHC class II+ cells, as well as expressions of chemokine receptor, MHC class II were not affected by single LPS injection or saline injection. These results suggest that the repeated antigen stimulation may not affect antigen-presenting ability by antigen-presenting cells, whereas it may lead influx of T cell subsets in the vagina. These accumulated T cells pool may contribute to form prequiescence of host immunity in the vaginal mucosa.