To better understand the process of karyotype evolution in Galloanserae (Galliformes and Anseriformes), we performed comparative chromosome painting with chicken chromosome-specific DNA probes and FISH mapping of the 18S-28S ribosomal RNA (rRNA) genes, telomeric (TTAGGG)n repeats, and cDNA clones of 37 genes for three anserid species, the domestic duck (Anas platyrhynchos), Muscovy duck (Cairina moschata), and Chinese goose (Anser cygnoides). Each chicken probe of chromosomes 1-9 and the Z chromosome painted a single pair of chromosomes in the three species except for the chromosome 4 probe, which painted acrocentric chromosome 4 and a pair of microchromosomes. The 18S-28S rRNA genes were localized to four pairs of microchromosomes in the domestic duck and Muscovy duck, and eight pairs of microchromosomes in the Chinese goose. The (TTAGGG)n repeats were localized to both telomeric ends of all chromosomes in the three species, and were additionally located in the interstitial region of the short arm of chromosome 1 in the domestic duck and in the centromeric region of chromosome 1 in the Muscovy duck. Comparative gene mapping of 37 chicken chromosome 1-4-linked and Z-linked genes revealed high chromosome homologies among three anserid species and also between the chicken and the three anserid species, although there were several chromosome rearrangements: pericentric inversion in chromosome 2, pericentric and paracentric inversions or centromere repositioning in the Z chromosome between the chicken and the anserid species, and pericentric inversions in chromosome 4 and the Z chromosome between the Chinese goose and the two duck species. These results collectively suggest that karyotypes have been highly conserved in Anseriformes and that chromosome rearrangements also occurred less frequently between Galliformes and Anseriformes after they diverged around 100 million years ago.
This study was conducted to determine the effect of selected antibiotic alternatives on growth performance and inflammatory gene expression in broiler chickens challenged with Eimeria oocysts from Coccivac® vaccine. A randomized complete block design with 6 treatments and 8 replicate pens per treatment was used. The treatments were; negative control (NC) with neither antibiotic nor antibiotic alternatives, Salinomycin positive control (PC), essential oil (Orego-Stim®), commercial yeast (AlphamuneTM), direct fed microbial (Avicorr®) and crude yeast extract. The study lasted 42 d and measurements were taken on d 0, 21 and 42. There was no significant difference in body weight (BW), daily gain (BWG) between treatments on d 21. From d 21 to d 42, BWG of birds treated with Salinomycin (2058 g) was higher (P<0.05) than Avicorr (1919 g) and Orego-Stim (1933 g) treated groups. Feed efficiency (g/kg) was improved (P<0.05) by Salinomycin (605) compared with NC (578) and Orego-Stim (578) treatments. Immune-related genes, interleukin-6 (IL-6) and 10 (IL-10), lipopolysaccharide-induced TNF-α factor (LITAF), toll-like receptor 4 (TLR-4) and interferon γ (IFNγ) were measured by PCR. On d 21, expression of IL-6 was reduced (P<0.05) in the Salinomycin, Avicorr, Alphamune and Orego-stim treatments relative to the NC and the crude yeast treatments. On d 42, LITAF was lower (P<0.05) in the Orego-Stim treatment group than NC. Birds in the crude yeast treatment had higher (P<0.05) expression of IL-10, IFN-γ and TLR-4 compared to the Orego-Stim treatment, but similar to NC. For digestibility trial, Salinomycin and crude yeast treatments had higher apparent ileal dry matter (DM), energy, N and P digestibility on d 21. These differences were not apparent on d 42. Overall, these results confirm the expected improved animal performance with antibiotic (Salinomycin) and further show reduced inflammation in the cecal tonsils with organic acid (Orego-Stim) treatment in broiler chickens.
An experiment was conducted to determine the available phosphorus (AP) requirement for post molted laying hens by using the broken line models, logistic model, saturation kinetics model and multivariate nonlinear mixed effects models. The experiment was conducted as a randomized complete block design with 5 dietary treatments (1, 1.5, 2, 2.5 and 3 g/kg of diet AP) and 6 replicates in each (72 hens per treatment). Hens were fed the experimental diets from 85 to 102 wk of age. Feed consumption and egg production were recorded daily, whereas body weight was obtained at the start of 85 and at the end of 102 wk of age and BW changes were calculated. Weekly, 1-d egg production weight was measured and egg mass was calculated. Egg qualities were measured at the end of 102 wk of age. According to the results, the optimal AP requirement from 85 to 102 wk of age for egg production, feed efficiency, egg mass, egg weight, average daily feed intake, shell breaking strength, shell thickness, egg shell percentage and BW changes were 2.1, 2.4, 2.1, 2.5, 1.8, 2.3, 2.1, 2.4 and 2.2 g/kg, respectively. The logistic model only was fitted to egg mass data and the AP requirement was 1.7 g/kg and was computed at 95% of the asymptotic response. AP requirement for maximizing the egg production and egg mass was 2.8 g/kg of diet, when multiple responses (egg production and egg mass) were analyzed simultaneously by using the multivariate nonlinear mixed effects models. The results of this study revealed that the broken line models fitted the data better than other models. According to the broken line models, the range of optimal AP requirement of post molted laying hens for various responses were 1.8 to 2.5 g/kg of diet.
The goal of this study was to determine the effects of phytase transgenic corn (PTC) in low phosphorus (P) corn-soybean meal diets on growth performance, and P and calcium (Ca) utilization by broilers. Six hundred and forty 1-day-old male broiler chicks were randomly divided into four groups, with eight replicates of 20 birds in each group, and fed for 42 days. Four treatments consisted of a positive control (PC), a negative control (NC), a PTC group and an exogenous phytase (EP) group. The PC group was fed with basal diet containing adequate amount of P. The NC group had 50% of the dicalcium phosphate supplement in the basal diet. The PTC group had the same inorganic P as the NC diet, but was substituted PTC for normal corn, so that the diet contained 500 phytase units (FTU) per kg of diet. The EP group was fed a diet identical to the NC diet but supplemented with 500 FTU of EP/kg of diet. The experiment showed that: there were no significant differences between the PTC and the PC groups, although a more favorable feed/gain occurred from the PTC group. The average daily feed intake and the average daily gain in the PC, PTC and EP groups were higher than those in the NC group (P<0.05). The Ca and P contents of tibia ash and serum in the PTC group were similar to those in the PC group, except for a higher tibia P percentage in the PC group at day 21 (P<0.05). These values were slightly higher than those in the EP group, except for a lower content of tibia P of the PTC group on day 42; the apparent retention of total phosphorus of the PTC and EP groups from day 17 to 21 was higher than that in the PC group (P<0.05). In conclusion, PTC as a source of phytase can replace the EP in broiler diets, especially in the starter phase of broiler chicks. The use of PTC could reduce the inclusion of inorganic P, improve the retention rate of P, and reduce pollution of the environment by farm animals without affecting the growth performance of broilers.
The distributions and frequencies of some endocrine cells in the small intestine of Muscovy duck during development were studied with immunohistochemical method using two types of antisera against Glucagon-like peptide-1(GLP-1) and Pituitary adenylate cyclase activating peptide (PACAP). In the small intestine, GLP-1 was first observed in the jejunum at E24 and in the duodenum at E30. However PACAP labeled fibers were first noted in the jejunum and the ileum at E30. The density of GLP-1immunoreactive cells reached the peak at hatch in the duodenum, while in the jejunum and ileum got the peak at 2d (P<0.05). The density of PACAP positive cells reached the peak in the jejunum and ileum at hatch and in the proximal duodenum at 2d and in the distal duodenum at 9d (P<0.05). The distribution of different endocrine cell type in the small intestine exhibit some particularities in the Muscovy duckling. These results can represent an useful information for future physiological investigations that will explore the exact role of PACAP and GLP-1 in the avian intestine during a critical period like the prehatch and posthatch.
Whey is known to be a by-product of making cheese from bovine milk. Whey protein isolated from bovine whey was used as feedstuff for animal production. But when intact whey was given as drinking water, the growth of chickens was restrained. As a large amount of lactic acid in animal feeds reduced feed intake of chickens, lactic acid in intact whey might result in the suppression of the growth and feed intake of chickens. In the present study, therefore, intact whey was dialyzed to exclude small molecular compounds like lactic acid and orally administrated to chickens to examine the influence of dialyzed whey on the growth and nutrient absorption from small intestine of chickens. Body weight gain of chickens given intact whey was significantly lower than that of birds given tap water. Feed intake showed similar tendency to body weight gain. Body weight gain of chickens given dialyzed whey was not significantly different from that of the control group. When chickens were administrated glucose-amino acid mixture solution with intact whey, plasma cystine level of the intact whey group was significantly higher than that of dialyzed whey group. It was concluded that the exclusion of small molecular compounds by dialysis would be available to exclude the adverse effect of intact whey for the growth of chickens.
Rice grain for feed has been used for chicken feed as a substitute for corn, since the nutritive values of corn and rice are similar. However, it is unclear whether rice grain for feed should be available for young chicks from the early stages of ages. It was reported that the preference for unpolished rice was low, but no information was available for paddy rice (PR) which is low in digestibility. In the present study, therefore, preference for PR and the passage of feed through the gastrointestinal tract were investigated. In order to improve this preference, the effect of mixing PR with a practical diet was compared with early learning for adapting to PR. In addition, it was confirmed that the passage rate of PR is improved by the addition of grit, an enzyme or lysine. As a result, replacing 60% of a practical diet with PR was found to significantly increase intake of feed in comparison with the practical diet alone. The preference for PR was very clear irrespective of whether early learning for adapting to PR occurred just after hatching or not. The addition of an enzyme improved the passage of feed through the whole gastrointestinal tract, although the addition of grit and lysine did not affect it. On the other hand, the passage of feed from the crop was not improved by any treatments. In conclusion, mixing PR and the practical diet improved feed intake and the passage of feed through the gastrointestinal tract was improved by adding enzymes in young chicks.
The effects of dietary untreated whole-grain paddy rice (WPR) on performance and histological intestinal alterations were investigated in Sanuki Cochin male chicks. At 2 weeks of age, chicks showing similar body weights were randomly divided into 3 groups of 10 birds each. The control group was fed with a basal diet (starter diet: CP 21%, ME 3000 kcal/kg; grower diet: CP 18%, ME 2850 kcal/kg; finisher diet: CP 15%, ME 2800 kcal/kg) and the other groups were fed with the basal diet diluted with WPR at 20% (starter diet: CP 17.8%, ME 2958 kcal/kg; grower diet: CP 15.4%, ME 2838 kcal/kg; finisher diet: CP 13%, ME 2798 kcal/kg) and 40% (starter diet: CP 14.6%, ME 2916 kcal/kg; grower diet: CP 12.8%, ME 2826 kcal/kg; finisher diet: CP 11%, ME 2796 kcal/kg). They were housed in individual cages under natural room temperature (around 5°C) with a daily lighting regimen of 16 h of light and 8 h of dark. The growth performance, relative length of the intestines and relative weight of the visceral organs to 100 g body weight did not differ except that the weight of the gizzard increased significantly (p<0.05) in the WPR groups. Most parameters of villus height, villus area, cell area and cell mitosis numbers of the WPR groups did not show a significant decrease. In scanning electron microscopic results, the morphology of the villus apical surface in the WPR groups did not show damage due to WPR and had similar cells to the control (protuberated cells). These results demonstrate that WPR can be diluted by up to 40% as a feed ingredient in chicken basal diets.
The present study was conducted to investigate the effects of two dietary lutein sources such as the commercial lutein and the emulsified crude extract of spinach containing lutein on the transfer of lutein into egg yolks as well as the antioxidant defense system in the liver of laying hens. A total of thirty-six, 24-week-old White leghorn hens were randomly assigned to a basal diet (CON) and that supplemented with a commercial lutein (LUT, 40 mg lutein /kg of diet) and the crude extract of spinach dissolved into oils with lecithin (ECE, 40 mg lutein/kg of diet) for 5 weeks. There was no difference in body weight and the relative live weight among dietary groups. The concentration of egg yolk lutein and yolk color significantly increased (P<0.05) in the LUT and ECE groups compared with the CON group. The LUT group showed a higher yolk lutein and much a lower variability of average yolk lutein content, although there was no significant difference in egg yolk lutein content between the LUT and ECE groups. In antioxidant activity, the specific activity of hepatic superoxide dismutase (SOD) in the LUT group was significantly (P<0.05) greater than that in the CON and ECE groups, whereas glutathione peroxidase (GPX) and glutathione S-transferase (GST) activities and lipid peroxidation were not affected by dietary sources of lutein. In conclusion, the dietary supplementation of lutein and the emulsified crude extract of spinach to laying hens resulted in a significant increase in the content of egg yolk lutein and yolk color, indicating that both supplements may potentially be applicable for the production of egg-enriched lutein in laying hens. This study also suggest that a commercial lutein more consistently produces the quality of lutein-enriched eggs and improves hepatic SOD activity compared with the emulsified crude extract of spinach.
Two-factor experiment was designed to examine from lipid metabolism, proinflammatory eicosanoids, and lipid peroxidation for investigating the effects of dietary oils and zinc levels of cardiovascular system of broilers. One hundred sixty 1-d-old male broilers were divided into 4 groups with 8 replicates of 5 birds fed one of the diets containing either corn oil or fish oil with one of 2 levels (75 mg/kg, 150 mg/kg) of zinc. Fish oil significantly decreased the levels of serum total cholesterol, triglyceride, high density lipoprotein-cholesterol, low density lipoprotein-cholesterol of broilers, decreased the contents of plasma prostaglandin E2, thromboxane B2, and phospholipase A2 in broilers when compared with corn oil. Zn level did not alter lipid metabolism, but significantly affected eicosanoid synthesis and lipid peroxidation of broilers. Zinc at 150 mg/kg significantly decreased the contents of plasma prostaglandin E2, malondialdehyde, and phospholipase A2 in broilers when compared to zinc at 75 mg/Kg. There were significant interactions between oil sources and zinc levels on production of serum triglyceride, high density lipoprotein-cholesterol, plasma 6-keto- prostaglandin F1α, phospholipase A2 and malondialdehyde. In conclusion, fish oil improved lipid profiles, reduced proinflammatory eicosanoid contents by inhibiting phospholipase A2 production in broilers; while zinc reduced the contents of plasma malondialdehyde, phospholipase A2, and then decreased the concentration of prostaglandin E2 of broilers.
Cassava pulp contains a lot of starch, but low amounts of protein and high fiber content which limits its use as a feedstuff for broilers. However, fermentation of this pulp with Aspergillus oryzae (A. oryzae) to improve its protein content may increase its usefulness in broiler diets. Therefore, two experiments were conducted to evaluate the potential use of fermented cassava pulp (FCP) in broilers. In experiment 1 the effects of FCP on nutrient digestibility and retention were studied. FCP was prepared using cassava pulp fermented with A. oryzae and urea for 4 days. Forty-nine fifteen-day old male chickens were placed in individual cages and assigned randomly to one of 7 dietary treatment groups (one control and six FCP: 40, 80, 120, 160, 200 and 240 g/kg) for 10 days. The results indicate that nutrient digestibility and retention decreased with increasing levels of FCP (P>0.05), but the decrease was not significant at dietary levels below 160 g/kg. Experiment 2 studied the effect of FCP in broiler diets on growth performance, carcass quality and blood biochemistry. Two hundred and seventy one-day old male chicks were randomly distributed to 6 dietary groups (one control and five FCP: 40, 80, 120, 160 and 200 g/kg) for 42 days. The results show that FCP could be used as an energy source with inclusion levels up to 160 g/kg in broiler diets having no effect on growth performance, carcass composition, meat color or blood biochemistry (P>0.05). Moreover, it was found that FCP had no detrimental effects on the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) of broilers (P>0.05). In conclusion, FCP can be used in broiler diets up to 160 g/kg without detrimental effects on nutrient digestibility and retention, growth performance, carcass quality or blood biochemistry.
It is known that thermal conditioning at an early age results in improved heat tolerance, and reduces mortality when re-exposed to heat in later life in chickens. However, the mechanism of thermal conditioning is not fully understood. The objective of this study was to investigate the effect of early thermal conditioning on physiological and behavioral responses in acute heat-exposed chicks. Six-day-old chicks (White Plymouth Rock) were exposed to high temperature at 40°C for 3 h while control chicks were kept at 30°C. Four days after treatment, both groups were challenged to high temperature at 40°C for 15 min. We found that the initiation times for behavioral responses (panting and wing-droop posture) in experienced chicks were later than those in control. At the end of heat-exposure treatment, the rectal temperature in experienced chicks was lower than that in control while there was no difference in respiration rate between the groups. Compared with control, experienced chicks had a lower level of plasma corticosterone. Gene expression levels of brain-derived neurotrophic factor, thyrotropin-releasing hormone, interleukin-6 and lipopolysaccharide-induced tumor necrosis factor were significantly lower in the brain of experienced chicks than in the control chicks. These results suggest that thermal conditioning may change response to subsequent heat exposure by altering the central thermoregulation system, resulting in an alleviation of heat stress.
Transplantation of primordial germ cells (PGCs), which are the progenitor cells of gametes, is a powerful tool for generation of transgenic chickens. However, the frequencies of transgene integration into the genome of purified PGCs still remain low. An in vitro culture system enabling chicken PGCs to propagate efficiently would be useful for efficient transgenesis of PGCs. In the present study, we optimized the culture conditions for chicken PGCs to enhance the proliferation and evaluated the germline transmission of cultured PGCs that proliferated for long periods of time. PGC-like cells (PGC-LCs), that have remarkably similar morphological characteristics to intact PGCs, could be derived by cultivation of blood containing PGCs obtained from 2.5-day-old chicken embryos according to the protocol of van de Lavoir et al. (2006). We determined which feeder cells and which growth factors were required to improve proliferation of PGC-LCs. Male PGC-LCs survival and proliferation were enhanced during culture in the basic medium containing either basic fibroblast growth factor (bFGF) alone or both bFGF and stem cell factor (SCF) on a feeder of buffalo rat liver (BRL) cells. Male PGC-LCs could be propagated in defined culture condition for extended periods. These cells expressed the germline-specific protein Vasa and undifferentiated cell marker stage-specific embryonic antigen-1 (SSEA-1) and pluripotency genes Nanog and PouV. Furthermore, Male PGC-LCs cultured for 225 d could migrate toward and colonize within recipient gonads and transmit to the next generation following transplantation. We succeeded in produce 3 offspring originating from long-term cultured PGC-LCs from a germline chimeric rooster (6%). The present study represents valuable steps toward defining a culture condition enabling PGC-LCs to propagate efficiently for long periods in vitro with maintenance of their commitment to the germline.
This study was designed to evaluate the effect of bacteriophage on macrophage-mediated inflammatory immune responses against intracellular pathogens. The intracellular survival of nonlysogenic, lysogenic Salmonella Typhimurium, and Listeria monocytogenes were evaluated in chicken macrophage HD11 cells treated with Salmonella bacteriophage P22 for 24 h at 37°C. The relative expression of inflammatory mediator-related genes (IL-1β, IL-6, IL-8, IL-10, LITAF, and iNOS) was estimated by using a qPCR. The production of inflammatory factors (IL-1β, IL-6, IL-8, IL-10, TNF-α, and NO) was determined by using ELISA kits. The numbers of invading nonlysogenic S. Typhimurium (ST), lysogenic S. Typhimurium (LY), and L. monocytogenes(LM) in HD11 cells were reduced by 0.90, 0.83, and 1.51 log units, respectively, after 1 h of infection at 37°C. The relative expression levels of inflammatory mediator-encoding genes (IL-8, IL-10, and iNOS) were increased in ST- and LM-infected chicken macrophage HD11 cells treated with P22. The level of NO production was increased to 26.8 μM at LM-infected HD11 cells treated with P22, which corresponded to the reduction of intracellular L. monocytogenes in HD11 cells. The results suggest that the bacteriophage P22 has the potential to reduce the numbers of intracellular pathogens, S. Typhimurium and L. monocytogenes. This study would provide valuable insights into the interaction between bacteriophages and macrophages and help to develop new strategies for enhancing the microbiological safety in poultry.
From the standpoint of poultry meat hygiene, amyloid deposition and bacterial contamination in livers of 197 mature white layer chickens from a slaughterhouse and 100 young broiler breeder chickens from 5 different retail butcher shops were examined. Amyloid deposition was detected in 1 liver from 2-years-old layer using alkaline Congo red staining and immunohistochemical examination, but no amyloid deposition was observed in 100 livers from young broiler. Total bacterial counts in the chicken livers were examined using nutrient, desoxycholate hydrogen sulfate and mCCDA agar plates, but no close relationship between amyloid deposition and bacterial contamination (counts and species) was observed in this study. These results suggest there is low incidence of systemic amyloid deposition in chicken liver from meat market.