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In this study, the high-temperature molten salt corrosion resistance of bare steels and steels with protective coatings, fabricated by thermal diffusion processes (boronizing, aluminizing and chromizing), were investigated and compared. Surface engineering through thermal diffusion can be used to fabricate protective coatings against corrosion, while alleviating issues around possible cracking and spallation that is typical for conventional thermal-sprayed coatings. In this regard, samples of low carbon steel and 316 stainless steel substrates were boronized, chromized, and aluminized through a proprietary thermal diffusion process, while some of the samples were further coated with additional thin oxide and non-oxide layers to create new surface architectures. In order to simulate the actual corrosion conditions in recovery boilers (e.g., from black liquor combustion), the surfaces of the samples sprayed with a modeling salt solution, were exposed to low-temperature (220 ∘C) and high-temperature (600 ∘C) environments. According to microstructural and X-ray diffraction (XRD) studies and results of hardness determination, the coatings with multilayered architectures, with and without additional oxide layers, showed successful resistance to corrosive attack over bare steels. In particular, the samples with boronized and chromized coatings successfully withstood low-temperature corrosive attack, and the samples with aluminized coatings successfully resisted both low- and high-temperature molten salt corrosive attacks. The results of this study conducted for the first time for the thermal diffusion coatings suggest that these coatings with the obtained architectures may be suitable for surface engineering of large-sized steel components and tubing required for recovery boilers and other production units for pulp and paper processing and power generation.

The present study was undertaken to investigate the effects of different levels of clove bud ( Syzygium aromaticum ) powder on yolk biochemical parameters and fatty acids profile, yolk oxidative stability, and ovarian follicle numbers in laying hens receiving different n-6 to n-3 ratios. For this purpose, a total number of 160 laying hens, 43 weeks of age, were assigned to 8 experimental diets with 5 cages of 4 birds each. Dietary treatments consisted of two ratios of n-6 to n-3 (16.71 and 2.35), three levels of clove bud (0.0, 2.0, and 4.0 g/kg), and also a high vitamin E content (200 mg/kg) in a 2 × 4 factorial arrangement during a 70-d feeding trial. Dietary inclusion of clove bud increased yolk vitamin E concentration ( P P P = 0.071). Administration of low n-6 to n-3 ratios reduced egg yolk cholesterol ( P = 0.058) and vitamin E ( P P P P P P P P P P P

Background: Mesenchymal stem cells (MSCs) have potential of self-renewal and differentiation into many cell types and can be used for cells therapy. Addition of epigenetic drugs can also convert these cells into cardiomyocytes. Objective: The aim of this study was to evaluate the effect of 5-azacytidine on differentiation of sheep fetal bone marrow MSCs into cardiomyocytes. Materials and Methods: Isolated bone sheep fetal marrow MSCs was cultured in DMEM: F12 medium. Passaged-3 cells were examined for their differentiation capacity into osteocytes and adipose cells. Surface antigens of isolated cells were analyzed using flow cytometry. Cells after third passage treated with 5 μM 5-azacytidine for 48h followed by medium without 5-azacytidine for twenty-one days. Expression of cardiac alpha-actinin and Troponin I (cTnI) were analyzed by immunohistochemistry. Results: MSCs expressed CD44, CD166 and weak expression of CD34 and CD45, apart from this expression a very weak expression of CD105 was also observed. Oil red for adipose cells and alizarin red staining for osteocytes indicated that the cells from all studied groups maintained the differentiation potential into adipose and osteocytes cells. Expression of Gata4, connexin 43, Atrial Natriuretic Peptide (ANP) was also detected by reverse transcriptase polymerase chain reaction and weak expression of troponinI. Sarcomeric alpha-actinin and cTnI were also partially detected by immunohistochemistry on these cells. Conclusion: This result indicated that addition of 5-azacytidine into culture medium could be effective on MSCs differentiation into cardiomyocytes.

This study aimed to investigate chemical composition and effect of different levels (0%, 10% and 20%) of raw grass pea (RGP) and heat-treated (120 °C for 30 min) grass pea seed (HGP) on nutrient digestibility, dressing percentage, relative internal organ weights, intestinal villous morphology and broiler chicks' performance. A total number of 200 day-old male chicks were raised under similar condition for 10 days. On day 11, chicks were randomly assigned to five dietary treatments and four replicates of 10 birds each. The result of chemical analysis indicated that Iranian grass pea seed has low levels of total and condensed tannin, and it may be considered as a good source of protein (36.1%) and energy (17.09 kJ GE/g). Heat treatment reduced (p < 0.05) the total and condensed tannin to 21% and 78% respectively. Grass peas seed had higher levels of nitrogen-free extract, P, Na, Mg and Zn than soya bean meal. The apparent digestibility of gross energy and lipid was affected (p < 0.01) by the treatment diets, and it was the lowest after feeding 20% of HGP (p < 0.05). The relative weight of breast and pancreas (p < 0.05) was affected by treatments. Percentage weight of breast and pancreas increased (p < 0.05) after feeding high levels (20%) of RGP and HGP. Substitution of 20% of RGP and HGP increased the duodenal crypt depth (p < 0.05); however, it had no suppressive effect on villus height as the absorptive surface of intestine. The feed conversion ratio was not affected by the treatments in the total experimental period. This study showed that, although the high level of grass pea seed caused a remarkable increase in the relative weight of pancreas and decreased the apparent digestibility of gross energy and lipid, it had beneficial effect on breast relative weight. It seems that heat processing is not effective method for improving quality of Iranian grass pea seed.

Summary As alterations of dietary electrolyte balance (DEB) can influence amino acid metabolism via changes the ions incur in their configurations, performance and immunological responses of broiler chicks might be affected. So, the current study was carried out to investigate the effects of different levels of sulphur amino acids (SAA) and DEB on performance, jejunal morphology and immunocompetence of broiler chicks. A total of 360 1-day-old male Ross 308 broiler chicks were randomly assigned to nine experimental treatments with four replicates of 10 birds each. Experimental treatments consisted of three levels of SAA (100, 110, and 120% of NRC recommendation, provided by methionine supplementation in diets with the same cysteine level) and three levels of DEB (150, 250, and 350 mEq/kg) that were fed during the entire of trial in a 3 × 3 factorial arrangement. Results showed that the relative weights of intestine and abdominal fat were decreased markedly (p

Dedifferentiation can be induced by small molecules. One of these small molecules used in this study in order to increase the plasticity of differentiation of stem cells was reversine. The objective of present study was to investigate the effect of different concentrations of reversine on the plasticity of ovine fetal bone-marrow mesenchymal stem cells (BM-MSCs). BM-MSCs were extracted from ovine fetal and cultured. Passaged-3 cells were evaluated for their differentiation potential into osteocytes and adipocytes cells. In the present study, BM-MSCs were culture plated in the presence of 0, 300, 600, 900 and 1200 nM of reversine. The number of viable cells was determined by MTT test after addition of different concentrations of reversine. Furthermore, expression of the nanog gene was evaluated. The culture without reversine was taken as the control group. Expression of nanog was analysed by immunocytochemistry. Multi-lineage differentiation showed that the BM-MSCs could be differentiated into adipose cells and osteocytes. Our results indicated that the addition of 1200 nM of reversine to medium significantly decreased overall proliferation compared to the other treatment groups (p > 0.05). Real-time PCR analysis showed that after addition of 600 nM of reversine significantly increased nanog expression compared to other treatments. All treatments received reversine were seen to be relative expression of nanog. Our findings confirm that low concentrations reversine increases the plasticity of ovine BM-MSCs.

This study was carried out to assess the effects of a blend of herbal essential oils (namely Thymus vulgaris, Mentha piperita, Rosmarinus offisinalis and Anethum graveolens) and different dietary lipid sources on the performance, ileal bacterial enumeration, intestinal histological alterations and immune responses in laying hens. For this purpose, a total of 150 laying hens were randomly allocated to six experimental treatments with five replicates of five birds each. Dietary treatments consisted of three levels of a mixture of essential oils (0, 100 and 200 mg/kg) and two sources of lipid (soybean oil and fish oil containing different ratios of n-6 to n-3 fatty acids) fed to the animals during an 80-days feeding trial. Findings indicated that dietary administration of fish oil not only increased significantly the spleen relative weight (p

Clove bud (Syzygium aromaticum) extract was added at concentrations of 0, 35, 75, and 115 μg/ml to ovine semen extenders in order to investigate the antioxidant activities of clove bud extract and its effects on semen quality parameters after cryopreservation of ram spermatozoa. The basic extender was composed of Tris, egg yolk, and glycerol. Two other extenders were prepared by substitution of egg yolk with either LDL or egg yolk+SDS. The DPPH inhibition test was employed to assess the antioxidant activity of clove bud extract. Results showed that, compared to vitamin E, clove bud extract had a higher antioxidant activity. Better sperm motility and movement characteristics (P

The current study was carried out to assess the effects of different levels of clove bud ( Syzygium aromaticum ) powder on performance, intestinal microbial colonization, jejunal morphology, and immunocompetence of laying hens receiving diets with different ratios of n-6 to n-3. A total of 160 laying hens, 43 weeks of age, were assigned to 8 experimental diets with 5 cages of 4 birds each. Dietary treatments consisted of two ratios of n-6 to n-3 (16.71 and 2.35) and three levels of clove bud (0, 0.2 and 0.4%) in a 2×3 factorial arrangement alongside a group receiving a high vitamin E content (200 mg/kg) in each n-6 to n-3 ratio, as the positive control, fed during a 70-d feeding trial. The in vitro study indicated that clove essential oil exhibited more than 10-fold higher antioxidant activity to inhibit 2-2-diphenyl-1- picric hydrazyl (DPPH) free radical than vitamin E ( P P P P P P P P P P Escherichia coli and Salmonella enumerations. Feeding clove bud, especially the 2% level, led to increase in villus height ( P P P P =0.08) and goblet cells ( P P P P P P P

The present study aimed at investigating the effects of different dietary crude protein (CP) and threonine (Thr) levels on the performance, immune responses and jejunal morphology of broiler chicks. A total of 432 broiler chicks were randomly assigned to a 3×3 factorial arrangement of treatments including three different CP dietary levels (90, 95, and 100% of Ross 308 recommendations) and Thr (100, 110, and 120% of Ross specifications) dietary levels. Performance parameters were recorded for the starter (1-12 days), grower (13-24 days) and finisher (25-42 days) periods. Birds were subjected to different antigen inoculations to evaluate antibody responses. At day 42 of age, two randomly-selected birds per replicate were slaughtered to measure carcass traits. Although Thr dietary supplementation had no marked effect on Newcastle antibody titers, particularly the supplementation of Thr up to 110% of Ross specifications improved (p

This study was designed to investigate the expression, activation and activity of matrix metalloproteinase-2 (MMP-2) in the heart of broiler chickens reared in cold conditions and fed with copper-methionine supplement at different levels. The chickens (n=480) were randomly allotted to six treatments and four replicates. Treatments included two rearing temperatures (i.e. normal and cold temperatures) each combined with three levels of supplemental copper-methionine (i.e. 0, 100 and 200mg/kg). On d 38 and 45 of age, four broilers from each treatment were sacrificed and their hearts were stored at -80°C. Right-sided heart failure, as evident from abdominal and pericardial fluid accumulation, was observed in broilers under cold stress and not receiving supplemental copper. This clinical observation was confirmed at molecular level through increased MMP-2 expression, activation and activity in this group. Birds reared under normal temperature, however, were not involved in right-sided heart failure nor benefitted from copper-methionine supplementation. In contrast, gelatin zymography and real-time PCR demonstrated that dietary supplementation with copper-methionine decreased pro-MMP-2 and MMP-2 in the heart of chickens reared in cold conditions. However, gelatin reverse zymography did not show any difference between treatments in tissue inhibitor of metalloproteinase-2. Level of supplementation showed similar effects on parameters determined. It is concluded that dietary supplementation with copper-methionine reduced right-sided heart failure at clinical and molecular levels in cold-stressed chickens.

High-energy diets of laying hens may improve roductive performance, although some negative effects may also appear with respect to egg quality and physiological parameters. Curcuma longa rhizome powder (CRP) has beneficial effects on health indices of the birds through antioxidant and antimicrobial properties, especially when the birds experience nutritional stress.Increasing dietary CRP enhanced egg quality by improving eggshell thickness and hardness but decreasing yolk cholesterol content (P0.05). The best feed conversion ratio was obtained in birds fed high-apparent metabolizable energy (AME) diets supplemented with 2.0 g kgAn improvement in the productive performance of laying hens fed high-energy diets might be associated with decreasing health indices and product quality, which could potentially be amended by nutritional modifications such as incorporating medicinal herbs in the feed. © 2016 Society of Chemical Industry.

The present study aimed to investigate the effects of dietary supplementation of different levels of specific IgY (sIgY) and nonspecific IgY (nsIgY) egg yolk antibody powder on growth performance, immune functions, and intestinal morphology of Escherichia coli O78:K80-challenged broiler chicks. Lyophilized antibody isolated by the water-dilution method was obtained from the eggs of laying hens hyperimmunized with E. coli O78:K80. A total of 392 broiler chicks were randomly assigned to 7 dietary treatments with 4 replicates of 14 chicks (7 males and 7 females) each. Before offering the experimental diets, 7-d-old broiler chicks (except the negative control) were challenged orally with 0.5 mL (10(9) cfu/mL) of E. coli O78:K80 suspension. The challenge was continued for an additional 7 d from d 14 to 21 with 1.0 mL of a late log phase culture (10(9) cfu/mL) until the level of E. coli in feces reached 10(5) cfu/g. The 6 challenged groups received a basal diet supplemented with 0 (as positive control), 0.1, 0.2, or 0.4% (wt/wt) sIgY from eggs of immunized hens or levels of 0.2 or 0.4% (wt/wt) nsIgY from eggs laid by the nonimmunized hens. The negative control group was fed with the same unsupplemented diet. Oral infection caused an increase in ileal E. coli enumeration, total blood leukocytes, heterophil:lymphocyte ratio, the concentration of serum and intestinal secretory IgA, and the numbers of jejunal goblet cells and lamina propria lymphatic follicles. After 3 wk of feeding, the levels of 0.2 and 0.4% sIgY and 0.4% nsIgY had the most suppressive effects (P < 0.01) on the ileal E. coli enumeration and secretory IgA concentration. However, serum IgA concentration was slightly decreased only at the presence of 0.4% sIgY and nsIgY. Dietary supplementation with at least 0.2% sIgY decreased (P < 0.05) the circulating heterophil:lymphocyte ratio. Inclusion of both sIgY and nsIgY increased the villus height:crypt depth ratio and decreased the jejunal goblet cells and lamina propria lymphatic follicle numbers, with the most pronounced effects assigned to sIgY-supplemented groups. The best feed conversion ratio was obtained when the dietary inclusion of at least 0.2% sIgY continued for 3 wk. The present results indicate that dietary administration of at least 0.2% sIgY for 3 wk improved the intestinal health indices and immunological responses of broiler chicks orally challenged by E. coli O78:K80.

The aim of the present study was to investigate the effect of small molecules: Reversine and 5-azacytidine (5-AC), in an indirect co-culture condition with the cardiac fibroblasts as well as non co-culture condition, in order to explore the effect of such molecules in the process of differentiation of the ovine bone-marrow mesenchymal stem cells (BM-MSCs) towards cardiomyocytes. Surface antigens of the isolated cells were analysed using flow-cytometry. In addition, following to three passages cells were examined for their differentiation capacity into osteocytes and adipose cells, in order to ensure the mesenchymal origin of the stem cells. Six types of treatments were carried out in the present investigation, such that, in the first treatment BM-MSCs were cultured for 28 days as control group; the second treatment was composed of culturing ovine fetal cardiac fibroblasts on inserts, aiming to use these inserts for culturing plates which were seeded with BM-MSCs (Chamber group). As the third treatment, BM-MSCs were supplemented with 10-μM 5-AC and incubated for 48 h. The fourth treatment was composed of supplementing BM-MSCs with the 600-nM reversine, incubated for 48 h, and subsequently the incubation was further extended for another 48 h in the presence of 5-AC. The fifth treatment was composed of supplementing the chamber group with 10-μM 5-AC and incubation for 48 h, and the last or the sixth treatment was such that chamber group was supplemented with 600-nM reversine and an incubation period of 48 h. Following to the incubation, medium was replaced with 10-μM 5-AC and further incubated for another round of 48 h. In all treatments, following to addition of the small molecules incubations were carried out for 28 days; same as controls. Expression of cardiac alpha-actinin was analysed by immunocytochemistry. BM-MSCs have shown to express CD44 and CD166 along with a weak expression of the CD90, CD34, in addition to CD45. Multilineage differentiation has indicated that BM-MSCs could differentiate into adipose and osteocytes cells as well. In the treatment 4 it was observed that FGF signalling involved genes and all cardiac-related genes (ANP, MYH6 and Troponin I) were significantly expressed, except connexin 43 compared to other treatments. All treatments received small molecules, either alone or as a co-culture were seen to express sarcomeric alpha-actinin. This finding was partially supported by immunocytochemistry. These results validate that reversine and 5-AC have an effect on ovine BM-MSC differentiation into cardiomyocytes. Copyright © 2016 John WileySons, Ltd.

The objective of the present study was to investigate the effects of different levels of copper (as supplemental copper-methionine) on ascites incidence and matrix metalloproteinase-2 (MMP-2) changes in the lungs of cold-stressed broilers. For this purpose, 480 1-day-old Ross 308 broiler chickens were randomly assigned to six treatments. Treatments consisted of two ambient temperatures (thermoneutral and cold stress) each combined with 0, 100, and 200 mg supplemental copper/kg as copper-methionine in a 2 × 3 factorial arrangement in a completely randomized design with four replicates. Ascites was diagnosed based on abdominal and pericardial fluid accumulation at 45 days of age. Fourty-eight broilers were killed at 38 and 45 days of age, and their lungs were collected for biological analysis. Results showed that MMP-2 increased in the lungs of ascitic broilers and that copper-methionine supplementation significantly reduced MMP-2 in cold-stressed broiler chickens. Treatments did not affect tissue inhibitor of metalloproteinase-2 (TIMP-2) at 38 and 45 days of age, and no difference was observed between 100 and 200 mg/kg copper-methionine treatments. In conclusion, copper-methionine at higher than conventional levels of supplementation decreased ascites incidence in low temperature through reduced MMP-2 concentration. Further research is warranted to investigate the effect of copper on MMP-2 concentrations in other tissues with high oxygen demand.

Summary This study was carried out to assess the effects of different levels of sanguinarine on antioxidant indices, immunological responses, serum biochemical parameters, ileal microbial counts and jejunal morphology of laying hens fed on diets with different levels of crude protein (CP). A total of 180 laying hens were subjected into nine dietary treatments with four cages of five birds each. Experimental treatments consisted of three levels of CP (85.0, 92.5 and 100% of Hy-Line W36 manual recommendation) and three levels of sanguinarine (0.00, 3.75 and 7.50 mg/kg) as a 3 × 3 factorial arrangement of laying hens which fed during a 70-day feeding trial. The in vitro study showed that sanguinarine exhibited sevenfold and threefold decreased antioxidant activities to inhibit 2-2-diphenyl-1-picric hydrazyl free radical as well as ferric ion reducing rather than butylated hydroxyl toluene. Although using the decremental levels of CP caused the increase in heterophil-to-lymphocyte ratio (p

The effect of probiotic supplements (0, 400, 1000 and 2000 gr Bioplus 2B ton feed providing 0, -1 1.28×10 , 3.2×10 and 4.6×10 cfu gr feed concentration) on egg quality and laying hen's performance was 6 6 6 -1 investigated on eighty white leghorn Hy-Line, W-36 strain. Evaluated traits were egg production, egg weight, egg mass, feed consumption, feed conversion ratio, shell thickness, shell hardness, Haugh unit, egg cholesterol, plasma cholesterol, plasma triglyceride and histological changes of duodenum. Although, using the different levels of probiotic caused highly significant increase (P

Mastitis is a complex inflammatory disease of the mammary gland that is caused by the invasion of pathogens. This leads to reduced synthetic capacity, compositional changes and increased somatic cell counts (SCC) in milk. Toll-like receptor 4 (TLR4) is a cell surface receptor that recognizes lipopolysaccharides (LPS) of gram-negative bacteria. Its role in pathogen recognition and the subsequent immune response and differential expression of the gene during mastitis have prompted the investigation of TLR4 gene as a candidate to improve mastitis resistance in dairy cattle. The aim of this study was to analyse the possible association of a single nucleotide polymorphism (SNP) in putative co-receptor-binding region 2 (T4CRBR2) of the TLR4 gene with somatic cell score (SCS) and milk-related traits in 408 Iranian Holstein cows. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was performed for genotyping. The effect of the genotype on the traits of interest was analysed using the general linear model (GLM) procedure of SAS software. The B allele frequency was 0.634 and the distribution of genotypes was not in Hardy-Weinberg equilibrium in the overall population. The B allele of the SNP was associated with higher 305-day milk yield and breeding value for milk yield, and lower fat percentage and lower SCS, as compared with allele A. The association between TLR4 polymorphism with SCS and milk production traits reported in this study suggests that this SNP has the potential to be used as a marker for selection, based on molecular information. Keywords : TLR4 gene, mastitis, candidate gene, milk-related traits, single nucleotide polymorphism, SNP

An experiment was conducted to assess the optimal levels of dietary lysine (Lys) in Japanese quail from 7 to 21 days of age. A dose-response diet was formulated to be adequate in all amino acid concentrations with the exception of Lys. Different levels of supplemental L-Lysine.HCl were added to the dose-response diet at the expense of corn starch, sodium bicarbonate, and NaCl to create 6 levels of Lys ranged from 0.91% to 1.51% in diet. Optimal Lys for feed conversion ratio, breast meat yield, and leg meat yield were estimated at 1.15%, 1.21%, and 1.16% of diet, respectively, based on linear broken-line regression. With quadratic broken-line regression, the Lys requirements for body weight gain, feed conversion ratio, thigh meat yield, and breast meat yield were estimated at 1.27%, 1.21%, 1.32%, and 1.34% of diet, respectively. Overall, Lys requirements of starting Japanese quail may be at least 1.34% of diet for optimizing carcass attributes fed low-CP dose-response diet.

This study was conducted to investigate the effects of different levels of black cumin seeds (Nigella sativa L.) on performance, intestinal Escherichia coli count and morphology of jejunal epithelial cells in laying hens. A total of 100 Leghorn laying hens (Hy-Line W-36) of 49 weeks old were randomly distributed among five cage replicates of five birds each. Experimental diets consisted of different levels (0%, 1%, 2% and 3% of diet) of dietary black cumin inclusion. The experimental period lasted for a total of 10 weeks, and egg quality indexes and laying hens' performance were measured as two 35-day trial periods. At the final day, two hens per replicate were slaughtered to investigate the influence of dietary treatments on intestinal E. coli colonization and morphology of jejunal cells. Although dietary black cumin in all supplementation levels decreased (p < 0.05) the enumeration of ileal E. coli, the morphological and histological alterations in small intestine such as enhancement of villus height to crypt depth ratio, increased goblet cell numbers and proliferation of lamina propria lymphatic follicles were observed after dietary supplementation with at least 2% black cumin. Dietary treatments decreased (p < 0.05) the concentration of serum cholesterol and triglycerides and increased (p < 0.05) serum HDL concentration and relative weight of pancreas; however, the egg yolk cholesterol was not influenced by dietary treatments. In addition, dietary supplementation with black cumin improved (p < 0.05) eggshell quality and Haugh unit. The best feed conversion ratio was obtained when diets were supplemented with 2% black cumin. This improvement was due to the increase (p < 0.05) in egg mass and contemporaneous decrease (p < 0.01) in feed consumption. The present results indicated that regardless of supplementation level, dietary inclusion of black cumin decreased E. coli enumeration in ileal digesta and improved serum lipid profile and eggshell quality, whereas the best intestinal health indices and haying hens' performance were obtained by at least 2% black cumin seeds.

This experiment was conducted to evaluate the effects of different levels of turmeric rhizome powder (TRP) on production performance, egg quality and some serum metabolites of older laying hens. A total of 240 hens (Hy-Line W-36) in their second laying cycle were randomly assigned to 5 dietary treatments (basal diet supplemented with 0.0, 0.5, 1, 1.5, and 2 g kg-1TRP) with 12 replicates and 4 birds each. Results showed that 2 g kg-1 of TRP decreased (P

Background: Chicken antibodies have many advantages to the mammalian antibodies and have several important differences against mammalian IgG with regard to their specificity and large-scale production. In this study, the production, purification, and HRP conjugation of polyclonal IgY against hepatitis virus surface antigen (HBsAg) were carried out. Materials and Methods: Single Comb White Leghorn hens were immunized intramuscularly with hepatitis B vaccine in combination with Freund's adjuvants. Blood and eggs were collected before and during ten weeks after the first immunization. Results: A highly purified of 180 KDa with specific activity of 200 mIU/ml was obtained by our purification protocol. One milligram of the purified IgY was labeled with horseradish peroxidase (HRP). Sandwich ELISA was used to determine the optimum titer of anti-HbsAg IgY-conjugate which was found to be 1:20. Conclusions: This study showed that laying hens can be used as an alternative source for production of polyclonal antibodies against HBsAg and anti-HBs IgY could be labeled with HRP enzyme and could subsequently be used successfully as secondary antibody in ELISA for detection of HBsAg in the patients sera.

Alpha-1-antitrypsin (A1AT) as a strong protease inhibitor plays a major role in the protection of tissues against proteolytic destruction by neutrophil elastase. Existence of this protein in the mammary gland may increase the survival of milk proteins such as lactoferrin and lysozyme. The biological role of A1AT in tissues such as the mammary gland and results from previous quantitative trait loci (QTL) studies have provoked an investigation of A1AT as a candidate gene influencing milk production traits. The present study assessed the association of a single nucleotide polymorphism (SNP) at position 5504 of the A1AT gene with 305-day milk yield, milk fat and protein percentage and somatic cell score (SCS) in 408 Iranian Holstein cows. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used for genotyping. The effect of the genotype on the traits of interest was analysed using the general linear models (GLM) procedure of SAS software. The frequencies of alleles A and B were 0.633 and 0.367, respectively, and genotypes showed a significant deviation from Hardy-Weinberg equilibrium, which can be a result of selection for milk production traits. Results of association analysis showed a significant relationship between the SNP in the A1AT gene, and fat and protein percentage. Cows of genotype AB had higher milk fat percentage than those of genotype AA. Cows with genotype AA showed a lower milk protein percentage than those carrying genotype AB. When the association of this polymorphism with fat and protein percentage is considered, the SNP could be implemented as a marker in breeding programmes for these traits. Keywords : A1AT gene; candidate gene; mammary gland; PCR-RFLP