Immediately after hatching, neonatal chicks can find their food and control food intake, but the mechanisms for feeding are not completely understood. Food intake regulation in the brain involves neuropeptides. While some neuropeptides have effects similar to that observed in mammals, others have an opposite effect. Since the neonatal chick is precocial, the ability to obtain food is very important. However, the orexigenic factors are limited to neuropeptide Y, opioid, prolactin releasing peptide and gonadotropin-inhibitory hormone. The effects of anorexigenic peptides were well conserved in the neonatal chick. The higher food intake observed in broiler chicks can be explained by the lower expression of anorexigenic neuropeptides rather than the higher expression of orexigenic neuropeptides.

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A total of 250 chicken intestinal specimens were screened for the presence of lactic acid bacteria (LAB) by routine cultural, morphological and biochemical reactions. Based on the results, 75 isolates were identified as LAB and were characterized for their probiotic potential. During preliminary investigations, the viability of the isolated LAB strains under different environmental and stress conditions was evaluated. Three of the strains which appeared resistant to acidic pH values and high bile salt concentrations were selected for further detailed studies. Based on the biochemical reactions these strains were identified as, Lactobacillus acidophilus RNL26, Lactobacillus fermentum RNL 44, and Lactobacillus salivarius RNL 49. All three strains demonstrated enhanced inhibitory activity against gram positive species including Clostridium perfringens, Staphylococcus aureus and Listeria monocytogene, while L. fermentum RNL 44 was also inhibitory towards gram negative bacteria; Salmonella enteritidis and S. typhimurium. The antibacterial effect exerted by L. acidophilus RNL26 and L. salivarius RNL 49 appeared to be due to bacteriocin or bacteriocin like substance, as the neutralized and catalase treated supernatant fluid of both the strains retained their antibacterial activity. All three strains were further characterized for their cholesterol removal, aggregation, co-aggregation, and cell surface hydrophobicity under in vitro conditions. According to our results L. fermentum RNL 44 appeared to be a superior probiotic candidate compared to the other two studied probiotic strains, Lactobacillus acidophilus RNL26 and Lactobacillus salivarius RNL 49.

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This experiment aimed to determine the effects of restricted feeding a molt diet on molt induction in laying hens. Single Comb White Leghorn hens (age, 61wk) were housed in individual cages and randomly divided into 3 groups (2 treatments and 1 control group). After a 4-wk preliminary period, the control group was continuously fed a layer ration based on corn and soybean meal ad libitum. Molting was induced in the treatment groups by starvation (MS) or with feeding (MF). In the MS group, the feed was withdrawn for 2wk; this was followed by feeding of the layer ration skip-a-day for 1wk and then ad libitum. The MF group was fed a low-protein and low-energy diet comprising corn, wheat bran, and corn gluten feed 60g/hen/d for 4wk; this was followed by ad libitum feeding of the layer ration. Egg production, egg quality, and feed intakes were measured throughout the experimental period; serum estradiol-17β concentration, heterophil: lymphocyte (H:L) ratio, ovary and oviduct weights, and ME_n intake were measured during the molting period. During molting, body weights of the MS and MF groups were significantly (P<0.01) reduced than that of the control group. On d 10 of molting, the H:L ratio of the MF group was significantly (P<0.01) lower than that of the MS group. On d 14, the ovaries and oviducts of the MS and MF groups were distinctly (P<0.01) lighter than those of the control. On d 6, serum estradiol-17β of the MS and MF groups decreased regardless of the treatment. The energy intake for the MF hens was lower than requirement level and just enough for the basal metabolism. Therefore, the MF hens also completely went out of production during the molting period and arrest period was the same in the MS and MF groups.

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The aim of this study was to investigate the possible hypocholesterolemic effects of Rhodobacter capsulatus on cholesterol and triglycerides concentrations in serum, egg-yolk, and fatty acid composition in egg-yolk of quails. A total of 60, 10-week-old laying Japanese quails (Coturnix japonica) were randomly assigned into 3 treatment groups (20 quails/group), and fed diets supplemented with 0 (control), 0.02, and 0.04% R. capsulatus for 6 weeks. Eggs and blood from each quail were collected at the end of the 6-week feeding period for chemical analysis. The cholesterol fractions in egg-yolk and serum were measured by enzymatic assay, and the fatty acid composition in egg-yolk was determined by gas chromatography. The results revealed that the supplementation of 0.04% dietary R. capsulatus reduced (P<0.05) cholesterol and triglycerides concentrations in serum and in egg-yolk. High-density lipoprotein cholesterol was increased, and low-density lipoprotein cholesterol and the atherogenic index were decreased (P<0.05) by dietary R. capsulatus. Hepatic cholesterol was also reduced (P<0.05) by 0.04% R. capsulatus. Yolk color was improved (P<0.05) by 0.04% R. capsulatus supplemented diet. The concentrations of monounsaturated fatty acids and polyunsaturated fatty acids (PUFA) were increased (P<0.05) in egg-yolk of the quails fed the 0.04% R. capsulatus supplemented diet than the control diet. The ratio of PUFA to saturated fatty acids in egg-yolk was improved (P<0.05) by 0.04% R. capsulatus supplemented diet. Therefore, the supplementation of dietary R. capsulatus may be a feasible means of producing quail eggs with lower cholesterol and higher PUFA content for health conscious consumers.

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A variety of factors can affect feed efficiency in poultry; among them is β-Glucan. β-Glucan in feeds is often poorly digest and has deleterious effects on nutrient absorption. Supplementation of diets with proper enzyme can enhance nutrient digestion and absorption. The aim of this study was β-Glucanase production from Aspergillus niger and Trichoderma longibrachiatum (GPβ-Glucanase), as well as its in vitro and in vivo assessment. Yeast biomass was produced using Zapek medium with Glucose and inoculated in Erlenmeyer flasks (repressed conditions) with above fungi. The mycelia then transferred to Erlenmeyer flasks containing Zapek medium supplemented with 2% barely β-Glucan and incubated (induction conditions), and enzyme recovered from the medium. The mean activities of GPβ-Glucanase and commercial β-Glucanase from Bacillus subtillis (ZYβ-Glucanase) were recorded as 1348±5.12 and 1251±5.31BGU¹/g respectively. Chick model was used for in vivo assessment. 540 Broiler chicks were fed one of nine diets in a 3×3 factorial arrangement from 1 to 49 days of age. The factors were: enzyme addition (0, ZYβ-Glucanase and GPβ-Glucanase) and level of hull-less barley (HB) in diet (0, 40, and 60%). The results showed that supplementation of diets containing 40% HB either with commercial or produced enzyme led to significant (P<0.05) increase in weight gain and feed intake, whereas significant (P<0.05) decrease feed efficiency, however no significant differences were observed between two kinds of enzyme. Conclusion was that GPβ-Glucanase is of great potential and comparable to ZYβ-Glucanase for β-Glucan hydrolysis.

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An experiment was conducted to determine the influence of organic acid salt supplementation on the performance and gut health of broiler chickens. One hundred and twenty day old commercial Vencobb-100 broiler chicks were randomly distributed into three groups having four replicates of 10 birds in each group. Control (C) birds were offered standard basal diet and treatment 1 and 2 (T₁ and T₂) were having diets with ammonium formate or calcium propionate (3gm/kg diet). Organic acid salt supplementation increased (P<0.05) live weight, live weight gain at day 21, whereas no significant difference was noted at day 42. Cumulative feed intake was higher (P<0.01) in treatments up to 3^rd week but afterwards in control. Feed conversion ratio (FCR) at day 42 was better in treatment groups (P<0.05) compared with control. Organic acid salt reduced coliform count in feed compared to control (P<0.05), whereas clostridium count was unaffected (P>0.05). Ammonium formate supplementation lowered (P<0.05) Escherichia coli (E. coli) count in gut but clostridium count was unaffected (P>0.05). Histology of intestinal parts revealed that organic acid salt supplementation increased (P<0.05) villus height of different segment of small intestine compared with control. pH of different segments of gastrointestinal (GI) tract was unaffected by organic acid salt supplementation. Results of present experiment indicated that use of single organic acid salt i.e. ammonium formate or calcium propionate in the diet lowered feed intake but body weight gain was comparable as control birds, and thus improved feed conversion ratio. It also reduced bacterial and fungal count in feed and gut which improved villus height and helped in better nutrient utilization.

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The apparent and true amino acid digestibilities of silver fish meal and meat cum bone meal were determined using adult caecectomized roosters. Each test ingredient was offered to six caecectomized and six intact cockerels individually. The apparent digestibilities of indispensable amino acids of fish meal, with the exception of methionine and threonine were significantly higher in caecectomized than in intact birds. Whereas the apparent digestibilities of methionine, cystine, threonine, valine and serine of meat cum bone meal were higher in intact birds in comparison to their caecectomized counterparts. The true digestibilities of all the amino acids of fish meal were similar between caecectomized and intact birds. In contrary, except arginine and phenylalanine, all the essential amino acids of meat cum bone meal had higher digestibility in intact as compared to caecectomized cockerels. The intact cockerels underestimated the apparent amino acid digestibilities of fish meal, while overestimated that of meat cum bone meal. When true amino acid digestibility was taken into account, no significant difference was observed for fish meal between caecectomized and intact cockerels. On the other hand, the intact cockerels overestimated the digestibility of meat cum bone meal. These results suggested that the amino acid digestibility values of meat cum bone meal and fish meal determined using caecectomized cockerels might be appropriate and reliable for poultry diet formulations based on apparent digestible values. It also suggests that when the poultry diets are formulated on the basis of true digestibility values, the digestibility data of meat cum bone meal generated from caecectomized birds and that of fish meal generated either from caecectomized or intact cockerels can be effectively applied.

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To implicate histamine and its receptors in feed intake and nutrient transport, White Leghorn cockerels of the same age and body weight were grouped randomly into six groups. The first group was injected intraperitoneally with histamine (30mg/kg/body weight) for five consecutive days (equally 3 times within 24h). Similarly the second group was treated with H₁-receptor blocker at the rate of 60mg/kg body weight; the third was with histamine on priming with H₁ blocker as above; the fourth was with H₂ blocker at the rate of H₁; the fifth was with histamine primed with H₂ blocker as above; and the sixth was sham-treated control. Histamine suppressed feed intake (P<0.05). A significant recovery in feed intake was noticed with the priming of H₂ blocker. Food passage time also reduced significantly with the administration of histamine and this was significantly checked with the priming of both H₁ and H₂ blockers. The uptake calcium (Ca⁺⁺) and phosphorus values at 15, 30 or 45 minutes post-infusion stages did not differ between histamine and control groups. However, both H₁ and H₂-receptors blockers priming to histamine or even alone H₂ blocker improved the uptake of Ca⁺⁺ (P<0.05) at all stages compared to histamine or control group. But in case of phosphorus, priming of H₁ blocker with histamine failed to show any significant effect whereas H₂ blocker priming to histamine reduced the uptake at all stages. Glucose uptake was significantly (P<0.05) greater in histamine-treated group at all stages as compared to control but priming of either H₁ or H₂ blockers to histamine failed to show significant change. In brief, histamine reduces feed intake, feed passage time but improves glucose uptake, and predominantly the H₂ blocker reversed the feed suppression but both H₁ and H₂ inhibitors reduced feed passage time, and also improved Ca⁺⁺ uptake.

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The aim of the present study was to determine the effects of dietary supplementation of lutein on reproductive performances in mature chickens. At 40 weeks of age, 15 Barred Rock roosters (n=5 per treatment) and 108 hens (n=36 per treatment) were randomly assigned to one of three groups and fed ad libitum a standard diet supplemented with 0, 30, or 120ppm lutein. Semen was collected from each rooster by abdominal massage twice weekly, and sperm analyses (concentration, viability, and motility) were performed on individual semen samples collected the day before (d0) and 19 (d19) and 29 (d29) days after introduction to diets. Semen collected on d31, d32, and d37 was pooled according to treatment, and used to inseminate 1 replicate of hens (n=12) per treatment. Eggs were candled at 9 and 14 days to determine fertility, and stage of embryonic mortality (early, mid, late) was assessed by breaking out all unhatched eggs. Although no significant difference in sperm concentration, motility, or viability was observed between treatments, roosters fed the 120ppm lutein diet tended to display a higher sperm motility and viability at d29 (P>0.05). To account for the large degree of variation between individuals, sperm analyses data for each rooster were also corrected to their initial value. Normalized data indicate that, although not significant, roosters fed the 120ppm lutein diet still tended to display a higher sperm viability at d29 (P>0.05). No significant effect of dietary lutein was observed on fertility, embryonic survival, or hatchability. These results indicate that unlike other antioxidants, dietary supplementation of lutein (at 30 or 120ppm) does not significantly improve reproductive performance in mature chickens, as measured here by sperm quality and fertility, nor does it improve embryo survival.

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The present study was carried out to develop techniques for introducing exogenous DNA into primordial germ cells (PGCs) and expressing the introduced DNA efficiently in the gonads of developing chicken embryos. PGCs circulating in the bloodstream (stages 14-15) were transfected with GFP gene in vitro or in vivo by lipofection or nucleofection. The manipulated PGCs successfully migrated to the germinal ridges and expressed GFP gene efficiently in the gonads of developing embryos. Intense GFP gene expression was observed in the gonads during the first 8 days following the transfection, during which period the sexual differentiation of gonads and germ cells (GCs) takes place. The GFP gene expression then gradually declined during subsequent embryonic development until hatching. When PGCs were transfected in vivo by lipofection with linearised plasmid DNA, GFP gene was detected in the gonads of 4.3% (19/442) of embryos examined at 20.5 days of culture, whereas less than 1% of embryos detected GFP gene in the gonads of embryos in which PGCs were transfected in vitro or with circular form plasmid DNA. In two of the embryos in which PGCs were transfected in vivo by lipofection with linearised plasmid DNA, GFP gene was expressed clearly in limited areas of the gonads of 20.5-day cultured embryos. The results obtained in this study suggest that the present in vitro and in vivo techniques for PGC manipulation provide a useful experimental system for studying gene functions in the sexual differentiation of gonads and GCs in early chicken embryos.

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The length, width and thickness of cortical bone at the central diaphysis, as well as the inner structure and bone density in the tibia of growing Japanese quail (Coturnix japonica) were examined from hatching to 100 days of age at 10-day intervals to investigate long bone growth in quail. The body weights were also measured. Five left tibiae in male and female quail were evaluated, respectively. The inner structure of the tibia was observed on enlarged transparent X-ray images. The bone mineral densities at the proximal epiphysis and central diaphysis were estimated by the hydroxyapatite density using the SXA method. The female weight exceeded the male weight, and a significant sexual difference was observed after 40 days of age. There were no significant differences between the sexes for the length, width and thickness of cortical bone in the central diaphysis. The length, width and thickness of cortical bone stopped increasing at 40, 60 and 30 days of age, respectively. In male and female quail, the growth plates in the distal and proximal epiphyses disappeared at 30 and 40 days of age, respectively. The medullary cavity in the female tibia became bright from 40 days of age when the female quail began to lay eggs, and this was considered to represent medullary bone. The bone mineral density at the proximal epiphysis in the male tibia stopped increasing at 40 days of age, whereas that in the female tibia continued to increase until 100 days of age. The female bone mineral density at the diaphysis significantly exceeded the male value from 10 to 100 days of age. From these results, we conclude that the heavy body weight and presence of medullary bone in the medullary cavity in the female tibia raised the bone mineral densities at the proximal epiphysis and central diaphysis.

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The aim of this study was to develop an antibody to gallinacin-3 which is one of the antimicrobial peptides in chickens. The antibody was raised in rabbit using a synthetic peptide of gallinacin-3 (Gal-3), and purified through an affinity column. Specificity of antibody was examined by competitive ELISA using Gal-3-HRP and synthetic Gal-3, or the tissue peptides isolated from the uropygial gland and the uterus. Immunostaining was performed on sections of the trachea, uterus, vagina, cloacal gland and uropygial gland. In the competitive ELISA, co-incubation of Gal-3-HRP with Gal-3 and tissue peptides extracted from uropygialis and uterus caused a clear decline of optical density (A450) value in a dose dependent manner. The epithelial cells in the trachea, uterus, vagina, cloacal gland and uropygial gland stained positive using the prepared gallinacin-3 antibody. Sections incubated with antibody absorbed with Gal-3 (control staining) resulted in negative staining. These results suggest that the antibody to gallinacin-3 prepared in the current study is useful for immunocytochemical identification of gallinacin-3 in chickens. The current immunocytochemical results suggest the presence of gallinacin-3 in the epithelial cells of trachea, oviduct, cloacal gland and uropygialis.

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Mitochondria have long been known to play a critical role in maintaining bioenergetic status under physiological conditions. Our previous studies have shown that acute heat stress increases production of mitochondrial reactive oxygen species (ROS) in the skeletal muscle of chickens. This increased ROS production may lead to nonspecific modification of lipids and proteins, which may then result in bioenergetic dysfunctions. If increased mitochondrial ROS production in heat-stressed chickens causes oxidative damage, changes in mitochondrial peroxidized lipids and oxidatively modified proteins can be detected. To study this, 3-week-old male broiler chickens (n=4-8) were exposed to acute heat stress (34°C for 18h) while control chickens were kept at thermoneutral condition (25°C). Skeletal muscle subsarcolemmal mitochondria were isolated and used to study mitochondrial malondialdehyde (MDA) and protein carbonyl groups. Mitochondrial thiobarbituric acid reactive substances (TBARS) formation was measured colorimetrically with 0.01% butylated hydroxytoluene (BHT) and expressed as MDA equivalent. To detect oxidation-sensitive mitochondrial proteins, polypeptides resolved by two-dimensional (2D) electrophoresis were immunostained with DNP-specific antibodies for carbonylated proteins using Western blotting. In heat-stressed chickens, mitochondrial MDA was 2.7-fold higher, and 82 mitochondrial proteins were oxidized when compared to that of control chickens. These results suggest that in heat-stressed chickens, increased mitochondrial ROS production leads to oxidative damage to mitochondrial lipids and proteins.

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Infectious bursal disease virus (IBDV) and Newcastle disease virus (NDV) are the most important viruses in poultry, causing catastrophic economical losses to farmers and to chicken breeding companies in Jordan. Fifteen commercial broiler chicken flocks were vaccinated twice against NDV and once against IBDV. Clinical signs of Newcastle disease appeared at 23-25 days of age, mortality and morbidity rates were 30-50% and 65-75% respectively. IBDV maternal derived antibody levels were determined at one day old using commercial Enzyme linked immunossorbant assay (ELISA) kit. Samples of bursas of Fabricius in acute stage were collected and evaluated histologically and the average bursa/body weight ratios were calculated and analyzed statistically. Newcastle disease virus antibody levels at acute and convalescent stages of disease were determined using hemagglutination inhibition (HI) test. Tracheas were also collected in the acute stage for performing NDV reverse transcriptase-polymerase chain reaction (RT-PCR). ELISA results at 1 day of age indicated that all tested flocks had low IBD maternal antibody titers. Histopathological examination of the bursas of Fabricius showed lesions characteristic of subclinical IBDV infection, ranged from moderate to severe lymphoid depletion of follicular lymphocytes, or minimal to absence of follicular lymphocytic presence as a sequel to necrosis. The HI titers for NDV from acute and convalescent sera were 1.9 to 3.3 and 5.3 to 6.9 respectively. Newcastle disease gene was also confirmed in tracheas using RT-PCR test. The results obtained from this study indicate that subclinical IBDV infection at an early age is a significant cause of decreased immune response to NDV vaccine, therefore leading to NDV infection in commercial broiler chicken flocks despite the fact that these flocks were vaccinated twice against NDV.

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