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The aim of this study was to investigate the variability and relationships between some egg physical (egg weight, width, length, shape index, and surface area) and eggshell parameters (weight and percentage, thickness, breaking strength, and L*, a*, and b* values) during the entire laying hen cycle. A total of 8,000 eggs was collected every 5 wk, from 30 to 81 wk of hen age (10 samplings of 400 eggs/house), in 2 identical poultry houses equipped with enriched cages. For the statistical analysis, ANOVA, Bivariate Correlation, Principal Component Analysis (PCA), and Hierarchical Cluster Analysis were used. An increase of egg weight, length, and eggshell lightness (L*) associated with a reduction of eggshell percentage, breaking strength, and redness (a*) was observed as the hen aged (P  < 0.05). Overall, the coefficients of variation resulted in <5% in width, length, shape index, and egg surface area; from 5 to 10% of egg weight, shell weight, shell percentage, shell thickness, L*, and b*; and >10% of eggshell breaking strength and a*. According to the PCA, the highest changes during the laying cycle are related to egg physical parameters (32%) and to eggshell breaking strength, percentage, and thickness (26%). The egg physical parameters appeared to be strongly correlated to each other, whereas a slight correlation between eggshell breaking strength and color attributes were evidenced (-0.231 and 0.289, respectively, for L* and a*; P  < 0.01). Hierarchical cluster analysis, based on principal components of the overall egg attributes, is hereby considered, and evidenced dissimilarities for eggs laid from peak production up for 39 wk of hen age from the eggs laid afterwards. The latter group could also be divided into 2 subgroups, one comprising eggs laid from 44 and 53 wk of hen age and the other from 58 wk to the end. In conclusion, the large dataset created in this study allowed to extrapolate some robust information regarding the variability and correlations of the egg physical and eggshell quality attributes throughout the entire laying hen cycle. [ABSTRACT FROM AUTHOR]

This work describes the use of different methods to study egg white proteins from hen, duck and quail. For this purpose, ~rotein content determination, sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE), Urea-polyacrylamide gel electrophoresis (UreaPAGE), amino acids composition and Fourier Transform Infrared (FTIR) Spectroscopy were used to compare egg white proteins from these poultry species. Protein content, ranging from 71.31 to 72.36%. Quail egg white showed the lowest protein concentration (71.31 % ). The highest protein concentration was observed in duck egg white, which reached 72.36%. The analysis by SDS-PAGE, egg white proteins presented a wide range of relative molecular masses. The main egg white proteins are ovalbumin, ovotransferrin, ovomucoid and lysozyme. The contents of the hydrophobic amino acids residues (Pro, Gly, Ala, Val, Ile, Leu, Phe) are 34.54%, 34.95% and 34.94% for egg albumin from hen, duck and quail, respectively. The migration in Urea-PAGE into cathode direction indicated that duck egg white protein and quail egg white protein were much faster than hen egg white protein referring to bigger positive charges. Also, the secondary structure of protein was observed by FTIR. [ABSTRACT FROM AUTHOR]

A rapid decline in egg production of laying hens begins after 480 d of age. Such a rapid decrease results predominantly from the ovarian aging, accompanied by endocrine changes, decreased yolk synthesis and accumulation, and the reduction in follicles selected into the preovulatory hierarchy. In this study, hens at 90, 150, 280, and 580 d old (D90, D150, D280, and D580, respectively) were compared for yolk precursor formation in the liver to elucidate effects of aging on laying performance. The results showed that liver lipid synthesis increased remarkably in hens from D90 to D150, but decreased sharply at D580 as indicated by the changes in triglyceride (TG) levels. This result was consistent with the age-related changes of the laying performance. The levels of liver antioxidants and total antioxidant capacity decreased significantly in D580 hens and the methane dicarboxylic aldehyde in D580 hens was much higher than that at other stages. The serum 17β-estradiol level increased from D90 to D280, but decreased at D580 ({itP}<0.05). The expression of estrogen receptor α and β mRNAs in the liver displayed similar changes to the serum 17β-estradiol in D580 hens. Expressions of the genes related to yolk precursor formation and enzymes responsible for fat acid synthesis were all decreased in D580 hens. These results indicated that decreased yolk precursor formation in the liver of the aged hens resulted from concomitant decreases of serum 17β-estradiol level, transcription levels of estrogen receptors and critical genes involved in yolk precursor synthesis, and liver antioxidant status. [ABSTRACT FROM AUTHOR]

Organophosphate-induced delayed neuropathy (OPIDN) is characterized by progressive axonal degeneration and demyelination of the spinal cord and sciatic nerves. The neuregulin 1/epidermal growth factor receptor (ErbB) signaling pathway is crucial for axonal myelination. In this study, we investigated whether the neuregulin 1/ErbB signaling pathway mediated the progression of OPIDN. Adult hens were given tri-o-cresyl phosphate (TOCP), a typical neuropathic organophosphorus compound, to induce OPIDN. The ErbB inhibitor lapatinib was administered to hens 4 h prior to and 4 days after TOCP exposure. The neuregulin 1/ErbB signaling pathway was examined for their role in maintaining spinal cord and sciatic nerve fiber integrity. Schwann cell line sNF96.2 was used as the in vitro cell model. The in vivo results showed that TOCP (750 mg/kg body weight, p.o.) induced prominent ataxia and significant axon degeneration in the spinal cord and sciatic nerves. Lapatinib (25 mg/kg body weight, p.o.) treatment attenuated OPIDN clinically and histopathlogically and partially prevented the TOCP-induced activation of neuregulin 1/ErbB signaling pathway. Lapatinib also prevented the TOCPinduced inhibition of neuropathy target esterase (NTE), a key enzyme during the development of OPIDN, and the disturbed metabolism of phosphatidylcholine in sciatic nerves. In addition, lapatinib was shown, in vitro, to protect sNF96.2 cells from TOCP-induced dedifferentiation through neuregulin 1/ErbB signaling. Our results suggest that neuregulin 1/ErbB, through regulation of NTE activity in the peripheral nervous system, mediates the progression of OPIDN. Thus, this signal may serve as a potential target for the treatment of OPIDN. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In ovarian follicle development, estrogen acts as a regulatory molecule to mediate proliferation and differentiation of follicular cells. ERα (estrogen receptor α) exerts regulatory function classically by binding directly to the estrogen response element, recruiting co-factors and activating or repressing transcription in response to E2. In this study, we used ChIP-seq to map ERα-binding sites in ovaries of Hy-line Brown commercial hens at 45 d, 90 d and 160 d. In total, 24,886, 21,680 and 23,348 binding sites were identified in the ovaries of hens at 45 d, 90 d and 160 d, which are linked to 86, 83 and 74 genes, respectively. The PPI network contains 47 protein nodes and 164 interaction edges, among which, AKT1 (V-Akt Murine Thymoma Viral Oncogene Homolog 1) and ACTN2 (Actinin Alpha 2) with the highest weight in the network, followed by CREB1 (CAMP Responsive Element Binding Protein 1), and EPHA5 (EPH Receptor A5) were identified. These genes are likely related to sexual maturity in hens. This study also provides insight into the regulation of the ERα target gene networks and a reference for understanding ERα-regulated transcription. [ABSTRACT FROM AUTHOR]

Hens of the laying hybrid ISA Brown were used in the study with the objective to evaluate eggshell quality, microbial contamination of eggshells, and penetration of microorganisms into the egg content in different housing systems (enriched cage: 60 hens, 10 hens per cage, 750 cm² per hen vs free range: 60 hens, 9 hens per m²) and at different hen ages (26 vs 51 weeks) during storage time (0, 2, 7, 14, and 21 days). A significant interaction between the housing system and age was observed in egg weight and most of eggshell quality measurements. However, microbial contamination and penetration were affected mostly by the housing system and storage time. The numbers of Escherichia coli (P < 0.001, 4.51 vs 2.75 log cfu/eggshell) and Enterococcus (P < 0.001, 2.56 vs 1.11 log cfu/eggshell), and the total number of microorganisms (P < 0.001, 5.04 vs. 3.65 log cfu/eggshell) were higher in free range eggs compared to enriched cage eggs, respectively. The counts of Escherichia coli (P < 0.001, 4.23 vs 2.91 log cfu/eggshell) and Enterococcus (P < 0.001, 2.31 vs 1.27 log cfu/eggshell) decreased with storage time. A positive correlation between the total number of pores and penetration of Escherichia coli in both housing systems was observed in the albumen. It can be concluded that the housing system and age of laying hens significantly affected eggshell quality. Microbial contamination presumably affects the penetration of microorganisms. The correlation between the number of pores and penetration is assumed to be affected by the microbial species. [ABSTRACT FROM AUTHOR]

Androgen plays an important role in animals, and its role is mainly via androgen receptor (AR) to achieve. In this paper, the expression of AR mRNA in various parts of the oviduct was analyzed by qPCR. Oviductal structure was observed by H&E staining. The distribution of AR in the cells was detected by immunohistochemistry. The results showed that the expression of AR mRNA was found in the infundibulum, magnum, isthmus, uterus and vagina of the oviduct. The expression of the AR mRNA in infundibulum was the strongest, and the vaginal expression was weak. The immunohistochemical results was consistent with the molecular expression of AR mRNA, the positive reaction in the infundibulum, isthmus and uterus is more intense, followed by the magnum, the vaginal reaction is weak. Positive responses in the sections were mainly focused on luminal epithelium, glands and vascular epithelial cells. This study revealed the molecular expression of AR and the distribution of intracellular proteins in the oviduct of the hen, which provides an important basis for the regulation of the physiological activities of poultry oviduct and the molecular mechanism of sperm storage. [ABSTRACT FROM AUTHOR]

The current study included estimating the antioxidant activity of yolk lipid for the quail egg, Coturnix japonica (quail), Gallus gallus L. (hen), Anas Platyrhynchos L. (duck) and Gygnus cygnus L.(goose). The yolk and the white of those were separated from each other and the yolk lipid was separated also. The antioxidant activity, reducing power, chelating of iron ions and scavenging of hydrogen peroxide of yolk lipid for fresh egg were studied. The effect of egg storage at laboratory temperature (25-30°C) and refrigerator temperature (4±1°C) on antioxidant activity of egg yolk lipid was studied. The results showed that there was a significant decrease (P˂0.05) in all the antioxidant activity tests with duration of storage compared to yolk lipid of fresh egg. The decrease was more obvious when storing the egg at lab temperature (25-30°C) compared with the stored egg in refrigeration (4±1°C). [ABSTRACT FROM AUTHOR]

Anti microbial drug resistance concerns scientists all around the world epically one used as livestock feed additives. Feed grade antibiotics are given in non therapeutic doses which lead to survival of pathogenic microbes which in turn develop drug resistance, thus necessitating researchers to search for alternative ways to feed grade antibiotics besides doing least compromise on growth parameters. Organic acids are used in poultry to lower the pH of intestinal tract which favours good microbes which in turn suppress pathogenic microbes thus evicting the use of antibiotics. They are used in poultry diets and drinking water to elicit a positive growth response, improving nutrient digestibility, performance and immunity in poultry. Literature shows that organic acids have more or less pronounced antimicrobial activity, depending on both the concentration of the acid and the bacterial species that is exposed to the acid. The variability in response of organic acids and its possible mechanisms are discussed. Scope of this paper is to provide a view of the use of organic acids in the prevention of enteric disease in poultry, the effect on the gastrointestinal tract (GIT), immunity and performance of broiler or laying hens. In the current review beneficial aspects of organic acids along with different dose combinations are discussed to promote its optimum utilization in poultry nutrition and production. [ABSTRACT FROM AUTHOR]

Phobia is a type of anxiety disorder characterized by circumscribed, marked fear or anxiety to a specific object or situation which is out of proportion to the actual danger posed by the concerned object or situation. Worldwide, the prevalence of specific phobia has been found to be 16% in 13–17 years olds. In India, specific phobia has been identified as one of the most common disorders in the school-going age group, with the prevalence of approximately 4.2%. Alektorophobia is the specific term for phobia to hen/chickens. We hereby report an 18-year-old female presenting with alektorophobia and successfully treated with graded exposure therapy. It has not been described in extant literature to the best of our knowledge.

Immunoglobulin Y (IgY) is the predominant antibody found in hen’s (Gallus domesticus) egg yolk. This antibody, developed against several microorganisms in hen egg yolk, has been successfully used as an alternative to immunoglobulins from mammals for use in immunodiagnostics and immunotherapy. Enteropathogenic Escherichia coli (E.coli) F4 is the main etiological agent associated with swine neonatal diarrhea, and it causes notable economic losses in swine production. The aim of the present study was to evaluate the relationship between humoral immune response and the activation of gut-associated lymphoid tissue (GALT) in laying hens intramuscularly immunized with E. coli F4. Adult laying Shaver hens were immunized with a bacterin based on an inactivated lysate E. coli F4 strain that was originally isolated from neonatal piglet diarrhea, following a recommended schedule. The percentage of B lymphocytes in blood and spleen homogenates was determined by flow cytometry. Villi histomorphometry and the size of germinal centers (GC) activated in GALT and the spleen were measured in histological samples either stained with hematoxylin/eosin or through immunofluorescence. Antibody and isotype-specific antibodies in serum and egg yolk were measured using indirect enzyme-linked immunosorbent assay (ELISA). Secretory and serum immunoglobulin A (IgA) were measured by ELISA tests. Laying hen with intramuscular immunization with E. coli F4 lysate, activated both mucosal and systemic protection. Mucosal protection was provided through B lymphocytes, and most of them were activated on Peyer’s patches and esophageal tonsils, in GALT. Furthermore, increased B lymphocyte number in the lamina propria of the gut, and increased intraepithelial plasmatic cell number, produced high levels of mucosal IgA. Activated B lymphocytes interacted with absorptive cells, immune cells, and microbiota in the gut, producing signals that were translated into a powerful physical defense by producing a greater volume of mucin from an increased number of goblet cells. Systemic protection was provided through B lymphocyte activation of spleen GC, which produced hugely specific IgY serum levels. One week later, this specific IgY was deposited in the yolk. This suggests that GALT is a key immunologic tissue inside the mucosal immune system, acting as the “command center” for humoral reaction.

A meta-analysis integrating results of 40 selenium (Se) supplementation experiments that originated from 35 different controlled randomized trials was carried out in an attempt to identify significant factors that affect tissue Se accumulation in chicken. Examined factors included: Se source (12 different sources examined), type of chicken (laying hens or broilers), age of birds at the beginning of supplementation, duration of supplementation, year during which the study was conducted, sex of birds, number of chickens per treatment, method of analysis, tissue type, concentration of Se determined and Se added to feed. A correlation analysis was also carried out between tissue Se concentration and glutathione peroxidase activity. Data analysis showed that the factors significantly affecting tissue Se concentration include type of chicken (P=0.006), type of tissue (P0.05), certain inorganic (sodium selenite), calcium selenite, sodium selenate and organic sources (B-Traxim Se), Se-yeast, Se-malt, Se-enriched cabbage and Se-enriched garlic as well as background Se level from feed ingredients were found to significantly affect tissue Se concentration. The Se accumulation rate (estimated as linear regression coefficient of Se concentrations to Se added to feed) discriminated between the various tissues with highest values estimated in the leg muscle and lowest in blood plasma. Correlation analysis has also shown that tissue Se concentration (pooled data) was correlated to Se added to feed (r=0.529, P

Both genetic background and maternal care can have a strong influence on cognitive and emotional development. To investigate these effects and their possible interaction, White Leghorn (LH) and Brown Nick (BN) chicks, two hybrid lines of layer hen commonly used commercially, were housed either with or without a mother hen in their first five weeks of life. From three weeks of age, the chicks were tested in a series of experiments to deduce the effects of breed and maternal care on their fear response, foraging and social motivation, and cognitive abilities. The LH were found to explore more and showed more attempts to reinstate social contact than BN. The BN were less active in all tests and less motivated than LH by social contact or by foraging opportunity. No hybrid differences were found in cognitive performance in the holeboard task. In general, the presence of a mother hen had unexpectedly little effect on behavior in both LH and BN chicks. It is hypothesized that hens from commercially used genetic backgrounds may have been inadvertently selected to be less responsive to maternal care than ancestral or non-commercial breeds. The consistent and strong behavioral differences between genetic strains highlights the importance of breed-specific welfare management processes.

Egg productivity is declined by stress. It has been reported that some food supplements can improve the egg productivity due to a reduction of environmental stress. We evaluated the effect of fermented waste mushroom bed (FWMB) as a dietary additive on egg productivity. Hens were fed control food (control group,n = 100) or 3% FWMB-added food (FWMB group,n = 100) for 16 months. The number of eggs, soft-shelled eggs, and broken eggs were recorded for 15 months. We also evaluated stress-related markers (ovotransferrin, lipid peroxide, and the heterophil-to-lymphocyte ratio). The FWMB group had slightly increased egg production compared with control hens. The FWMB group produced significantly less broken and soft-shelled eggs than the control group. All stress-related markers were significantly lower in the FWMB group than in the control group. Gut flora was also affected by FWMB feeding. The increased egg production and decreased proportion of broken and soft-shelled eggs might be related to the prevention of stressful conditions by FWMB. Hens were fed 3% FWMB added to the diet. Comparing the egg production between the control group and FWMB group in each month, blood stress markers were improved by FWMB feeding. [ABSTRACT FROM AUTHOR]

A study was conducted to investigate Fe requirements of broiler breeders. One-hundred-fifty-six Cobb 500 broiler breeder hens were individually placed in electrostatically painted cages at 22 weeks. The study was composed of an adaptation phase, in which hens were fed corn-soy-wheat bran diets until 35 wks. An Fe deficient mash diet (24.6 ppm Fe) was provided from 35 to 46 wk in order to induce a partial body Fe depletion. A production phase followed from 47 to 70 wk when hens were fed 6 diets with increasing Fe sulfate supplementation, which, upon analyses had 24.6, 48.6, 74.3, 99.6, 125.6, and 148.2 ppm Fe. Thirty hatching eggs from each treatment were randomly collected in the last wk of each production period and incubated. Hemoglobin and hematocrit were analyzed from 6 hens as well as all hatched chicks per treatment. Analyses of production and hatching data were conducted using quadratic polynomial (QP), broken-line (BL), and exponential asymptotic (EA) models. Effects of dietary Fe were observed for total eggs and total hatching eggs, egg yolk Fe content, and hen and chick hematocrit and hemoglobin (P < 0.05). These responses to added Fe were optimized when dietary Fe were 96.8, 97.1, 130.6, 122.6, 120.0, and 125.0 ppm (QP) and 76.4, 89.3, 135.0, 128.4, 133.8, and 95.0 ppm (BL) for total hatching eggs, egg yolk Fe content, and hen and chick hematocrit and hemoglobin, respectively. Optimization with the EA model was obtained for total hatching eggs, egg yolk Fe, and hen and chick hemoglobin at 97.9, 111.0, 77.9, and 96.3 ppm Fe for total hatching eggs, egg yolk Fe, and hen and chick hemoglobin, respectively. Adequate Fe levels are needed to maintain egg production as well as hatching chicks' indexes. Fe concentration in the yolk and diet are positively influenced. The average of all Fe requirement estimates obtained in the present study was 106 ppm total Fe, whereas averaged values for BL, QP, and EA models were 107, 113, and 97 ppm Fe, respectively. [ABSTRACT FROM AUTHOR]

Hens responded under multiple fixed-ratio schedules with equal response requirements and either a 1-s or a 6-s reinforcer. Upcoming reinforcer size was indicated by key color. Components were presented in a quasirandom series so that all four component transitions occurred. Postreinforcement pauses were affected by the upcoming and preceding reinforcer size, with longer pauses after large reinforcers followed by small reinforcers than when followed by large ones, and longer pauses after small reinforcers that were followed by small reinforcers rather than large ones. Pauses increased with fixed-ratio size and the effects of reinforcer size were larger the larger the ratio. When reinforcer size was not signaled-mixed fixed-ratio schedules-pauses were shorter after small than after large reinforcers. Signalling the upcoming reinforcer attenuated the effect of the previous reinforcer size on pause duration when small was followed by small and when either small or large by large, but enhanced the effect when large was followed by small. There was no effect of reinforcer size on pause duration when single fixed-ratio schedules were arranged. The effects of reinforcer size on pauses depends on the size and range of the fixed ratios as well as the exact procedures used in the study. [ABSTRACT FROM AUTHOR]

Keel bone fractures are a well-known welfare problem in modern commercial laying hen systems. The present study sought to identify genetic variation in relation to keel bone fracture susceptibility of 4 distinct crossbred and one pure line, and by extension, possible breeding traits. Susceptibility to fractures were assessed using an ex vivo impact testing protocol in combination with a study design that minimized environmental variation to focus on genetic differences. The 5 crossbred/pure lines differed in their susceptibility to keel bone fractures with the greatest likelihood of fracture in one of the 3 commercial lines and the lowest susceptibility to fractures in one of the experimental lines. Egg production at the henlevel did not differ between the crossbred/pure lines (P > 0.05), though an increased susceptibility to keel bone fractures was associated with thinner eggshells and reduced egg breaking strength, a pattern consistent among all tested crossbred/pure lines. Our findings suggest an association between egg quality and bone strength which appeared to be independent of crossbred/pure line. The findings indicate the benefit of the impact methodology to identify potential breeding characteristics to reduce incidence of keel fracture as well as the potential relationship with eggshell quality. [ABSTRACT FROM AUTHOR]

Geothermal energy is commonly harvested at either shallower depth (below 150ft/45.72m) for residential purposes (with ground source heat pumps), or deeper depths (beyond 8000ft/2.43 km) for Enhanced Geothermal Systems. The in-between depths are rarely visited due to high drilling costs, and the water harvested being unable to power turbines. Recent studies powered by the data released by the National Geothermal Data System (NGDS) opened a new opportunity of harvesting the geothermal potential in post-production oil/gas boreholes in Pennsylvania. We are interested therefore in whether it is feasible to connect the different heat sources with different temperature availabilities to distribute to spatially scattered end-users. Presented in this paper is a project that generates heat exchanger network configurations through mixed nonlinear programming (MINLP) problem formulation and optimization in Python. With the case intentionally simplified, the computational costs of the optimization was found to be marginal. [ABSTRACT FROM AUTHOR]

Synchronized yolk accumulation and follicle development are essential for egg production in oviparous species. In birds, yolk is incorporated into the oocyte by an avian specific yolk receptor (LR8), and it has been suggested that occludin (OCLN), a tight junction protein, mediates transfer of yolk material to the oocyte surface. OCLN may be a key regulator of yolk accumulation and follicle growth, however, the expression and regulation of OCLN in granulosa cells during various stages of follicle development is unknown. In the first experiment, we found that LR8 and OCLN mRNA were highest in small follicles within the ovary. In addition, OCLN decreased with increasing follicle size. OCLN mRNA was more abundant in the germinal disc region of the granulosa cell layer than the non-germinal disc region. In addition, we found epidermal growth factor (EGF) and activin B, decreased OCLN mRNA, while activin A increased OCLN. In the second experiment, restricted fed (RF) broiler breeder hens were randomly divided into two groups and one group remained on RF and the other was fed ad libitum (FF). OCLN expression in granulosa cells of 3–5 mm follicles of FF hens was lower compared to RF hens and yolk weights were higher in the FF group, however, LR8 mRNA in small whole follicles (<3 mm) did not differ between groups. In conclusion, the level of feed intake is related to or may directly regulate OCLN mRNA expression or may have an indirect effect through paracrine or autocrine factors in the ovary. [ABSTRACT FROM AUTHOR]

Copyright of Landbauforschung is the property of Thuenen Institut and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Immunoglobulin Y (IgY) is the predominant antibody found in hen's (Gallus domesticus) egg yolk. This antibody, developed against several microorganisms in hen egg yolk, has been successfully used as an alternative to immunoglobulins from mammals for use in immunodiagnostics and immunotherapy. Enteropathogenic Escherichia coli (E.coli) F4 is the main etiological agent associated with swine neonatal diarrhea, and it causes notable economic losses in swine production. The aim of the present study was to evaluate the relationship between humoral immune response and the activation of gut-associated lymphoid tissue (GALT) in laying hens intramuscularly immunized with E. coli F4. Adult laying Shaver hens were immunized with a bacterin based on an inactivated lysate E. coli F4 strain that was originally isolated from neonatal piglet diarrhea, following a recommended schedule. The percentage of B lymphocytes in blood and spleen homogenates was determined by flow cytometry. Villi histomorphometry and the size of germinal centers (GC) activated in GALT and the spleen were measured in histological samples either stained with hematoxylin/eosin or through immunofluorescence. Antibody and isotype-specific antibodies in serum and egg yolk were measured using indirect enzyme-linked immunosorbent assay (ELISA). Secretory and serum immunoglobulin A (IgA) were measured by ELISA tests. Laying hen with intramuscular immunization with E. coli F4 lysate, activated both mucosal and systemic protection. Mucosal protection was provided through B lymphocytes, and most of them were activated on Peyer's patches and esophageal tonsils, in GALT. Furthermore, increased B lymphocyte number in the lamina propria of the gut, and increased intraepithelial plasmatic cell number, produced high levels of mucosal IgA. Activated B lymphocytes interacted with absorptive cells, immune cells, and microbiota in the gut, producing signals that were translated into a powerful physical defense by producing a greater volume of mucin from an increased number of goblet cells. Systemic protection was provided through B lymphocyte activation of spleen GC, which produced hugely specific IgY serum levels. One week later, this specific IgY was deposited in the yolk. This suggests that GALT is a key immunologic tissue inside the mucosal immune system, acting as the "command center" for humoral reaction. [ABSTRACT FROM AUTHOR]

Process effluents recovery can be a tremendous source of revenue as well as a smart way to reduce their environmental footprint for industrial processes. Reusing effluents for heating purposes or reducing resource consumption can lead to substantial operating costs savings if the capital investments required to implement recovery networks are depreciated over an adequate period of time. This paper presents a mixed-integer linear programming model to design mass allocation and heat exchanger networks simultaneously. Mass streams are characterized by their composition and properties. A superstructure is presented to define the interactions between mass allocation and heat exchanger networks. Non-isothermal mixing can occur before and after the heat exchanger network. The objective function is the total annualized costs of both networks. It takes into account the annual operating costs for energy and mass requirements and the capital costs of the heat exchanger network. Two literature case studies are presented to demonstrate the model performances. [ABSTRACT FROM AUTHOR]

The variability of carbohydrate (oligosaccharides, insoluble fibres etc.) content in leaves depends on species and age of the plant as well as the collection season resulting in the need for a determination of the optimum incorporation rate in poultry diets. Important improvement of chicken productivity induced by the use of Moringa oleifera leaves in poultry farming led to an evaluation of its effects on the feed transit process. A total of 600 day-old ISA Brown chickens (layertype) were divided into three groups (M0, M1 and M2). The three groups were fed respectively with diet M0 (0% of Moringa leaves), diet M1 (1% of Moringa leaves) and diet M2 (2% of Moringa leaves). At d 56 and d 280, 100 birds per group were isolated. They were deprived of feed and had 2 h to feed again. At 1, 4, 8, 12 and 24 h after the latter feeding period, 20 birds from each cage were slaughtered and their digestive tract removed. Each segment (crop, gizzard, small intestine, caecum and rectum) was isolated. Wet digesta collected was weighed and emptied segments were weighed and/or measured. Results at 56 days indicate that birds fed with diets containing Moringa oleifera leaves had higher feed transit time and larger intestines compared to birds of M0. At 280 days, in spite of the similarity of small intestine and caeca sizes, M2 had the fastest feed transit and the lightest small intestine and caeca compared to M1. These results can be explained by anti-nutritive cumulative effects of these leaves. It can be concluded that Moringa oleifera leaves incorporated in poultry diets at 1% delay feed transit and improve anatomical structure of the gut. [ABSTRACT FROM AUTHOR]

The study aimed to determine the effects of dietary supplementation with high dose of inorganic chromium from a new additive (soya meal enriched with Cr (III) by biosorption) on lymphatic cells in caecal tonsil of laying hens. The feeding experiment was conducted over 4 weeks on 60 laying hens from Hy-Line Brown line, aged 18 weeks. All birds were kept in a furnished Battery Cage System, in a room with a controlled climate conditions and light regimen of 13–15L:11–9D and were fed either a basal diet – control group (n = 30) or the basal diet supplemented with chromium – Cr-treated group (n = 30). The dietary treatments for Cr-treated group consisted of the basal diet supplemented with 87.7 mg kg −1 chromium from a enriched soya meal (20.588 ± 0.212 mg of Cr(III) g −1 ). The samples of caecal tonsils were stained against chicken Bu-1, CD4, and CD8α antigens and the positive area fractions were counted. It was revealed that the population of CD4 + cells was significantly higher ( p < 0.001) by unchanged number of the Bu-1 + and CD8α + cells in caecal tonsils of chromium-supplemented hens. The obtained results showed that the supplementation with high dose of chromium from a enriched soya meal stimulates the adaptive immune system in the caecal tonsil what may enhance the response against potentially dangerous antigens. [ABSTRACT FROM AUTHOR]

The aim of the work was to analyse of changes in external and internal characteristics of eggs of autochthonous chicken breed Oravka during laying cycle. A total of 350 eggs were collected to study for egg weight in g, egg shape index in %, shell thickness in mm, yolk, albumen and shell weight in g and their proportion in the egg mass, yolk index in % and Haugh units score in 26, 31, 36, 41, 46, 51 and 56 weeks of age (60 eggs for each age). The results showed that as the laying cycle of hens progressed, the egg weight and egg shape index were increased (P<0.05). During laying period increased (P<0.05) yolk weight and yolk proportion in the egg mass, whereas the albumen proportion and Haugh unit score decreased (P<0.05) with age of hens. The quality of yolk and albumen decreased (P<0.05) as the laying cycle advanced. The other results showed that eggshell proportion and thickness were reduced (P>0.05), especially by the end of laying cycle. [ABSTRACT FROM AUTHOR]

For laying hens, the immediate aftermath and healing period of a keel fracture (KF) is characterized by reduced ability to perform species-specific behavior, access resources, and pain. However, the longer-term impacts, once the fracture is completely healed, are less clear. As well as acute pain and behavioral changes, a negative experience can shape future responses to putatively threatening stimuli, raising future fear, and anxiety levels during husbandry-related events. We aimed to determine whether hens that had previously sustained keel bone fractures, but were now outside of the peak age range for new fractures, showed higher fear and anxiety levels compared to intact hens. We also determined if healed keel bone fractures were associated with reduced production, changes in behavior and resource use. One hundred and fifty hens with a palpation score of 1 ("KF") and 150 hens with a palpation score of 0 (keel fracture free, " KFF ") were selected from a commercial farm at 63 wk of age and housed in 6 groups (3 × KF and 3 × KFF). We compared production (hen weight and feed consumption, egg quantity, quality and weight, floor eggs, shell thickness, and weight) and home pen behavior (behaviors and transitional movements) in both groups. Finally, we measured the responses of KF (n = 75) and KFF (n = 75) during tonic immobility, novel arena, and novel object tests. KF and KFF hens did not differ in their responses to the tonic immobility, novel arena, and novel object tests, nor were there differences between the 2 groups in home pen behavior and transitional movements. KFF birds were lighter and laid eggs with less eggshell membrane compared KF birds, but no differences were found between KF and KFF in any other production measures. We found no evidence that healed KFs were associated with detrimental welfare effects in laying hens, but further work is required to determine the mechanisms and implications of the lower body weight and egg shell membrane. [ABSTRACT FROM AUTHOR]

Highlights • The Chen's approximation has been widely used in research on the optimization of heat exchanger and mass exchanger networks because it allows easy handling of the numerical problems associated with the logarithmic term. • This work shows how a long forgotten function, the Lambert W-function (Euler, 1779; Lambert, 1758), revived recently by Corless et al.(1996), can be employed to provide an explicit solution involving the logarithmic mean. Abstract An explicit solution has been obtained for the logarithmic mean temperature difference method of heat exchanger calculation by making use of the Lambert W -function. The results might be of use where an explicit solution involving the logarithmic mean is required. [ABSTRACT FROM AUTHOR]

An experiment with laying hens and broiler breeders of two ages (young 22 vs. 36 weeks, old 83 vs. 64 weeks) and at temperatures of 20 and 28°C was carried out to evaluate the interactions between oviposition time (7:30; 11:30, and 15:30 h), age, and temperature on the one hand and egg quality on the other. A significant interaction (P ≤ 0.011) was determined in oviposition time. The highest number (25.8%) of eggs was laid at 7:30 h by young laying hens kept at 20°C and the lowest (3.7%) by young layers at 15:30 h kept in the same temperature. Time of oviposition was delayed by age and a higher temperature. Egg weight was significantly influenced by production type (P ≤ 0.001; 60.5 vs. 68.1 g), age (P ≤ 0.001; 59.4 vs. 69.3 g), oviposition (P ≤ 0.001; 66.5, 63.7, 62.8 g), and temperature (P ≤ 0.022; 65.1 vs. 63.6 g). The significant three-way interaction of age, oviposition, and temperature in Haugh unit score (P ≤ 0.013) and four-way interaction of production type, age, oviposition, and temperature (P ≤ 0.05) in specific gravity show that rather than by a single factor the valuable characteristics of egg quality are considerably affected by a combination of factors.