Hen Age Research Articles

The Influence of Hen Aging on Eggshell Ultrastructure and Shell Mineral Components.

The eggshell, which is a complex and highly ordered structure, is very important factor for food safety and egg marketing. This study investigated the changes in eggshell structure and shell components in relationship to hen age. For this study, we examined the histological change of the endometrium of the 30-, 60-, and 72-wk-old commercial layers, and analyzed the ultrastructure and ionic composition of their eggshells. The results showed that histological deformation, fibrosis, atrophy and elimination of micro-villi in the uterus endometrium were found through microscopic observation that was associated with increasing hen age. Concentration of blood-ion components such as Ca2+, Na+, K+, and Cl– ions did not change with age. Along with the results from the ultrastructure analysis of the eggshell, the palisade layer ratio and the density of mammillary knobs were significantly decreased in older hens. In addition, the type B mammillary knobs were frequently observed with increasing hen age. In the mineral element assay from the eggshell, Ca2+, S2–, and Co2+ significantly decreased with increasing hen age, whereas Na+, K+, and V2+ significantly increased. Therefore, the damages of endometrial tissue inhibit the processes of ion transmission and the crystallization of eggshell formation, resulting in a large and non-uniform mammillary knob formation. This means the conditions of endometrial cells affect the formation of the eggshell structure. In conclusion, hen aging causes the weakness of the eggshell and degrades the eggshell quality.

Expression of pro- and anti-inflammatory cytokines and chemokines during the ovulatory cycle and effects of aging on their expression in the uterine mucosa of laying hens

The aim of this study was to examine whether cytokines and chemokines expressed in the uterine mucosa play a role in the process of eggshell formation in the chicken uterus. Changes in the expression levels of pro- and anti-inflammatory cytokines and chemokines in the uterine mucosa during an ovulatory cycle (experiment 1) and effects of aging on their expression (experiment 2) were examined. In experiment 1, the expression of the pro-inflammatory cytokines IL1β, IL6, TNFSF15, and IFNγ, and a chemokine CX3CL1 was found to increase during eggshell biomineralization (16 h following oviposition), while anti-inflammatory TGFβ2 expression was found to increase at 4 h following oviposition. In experiment 2, a higher expression of the anti-inflammatory cytokines TGFβ2 and TGFβ3, and chemokines CXCLi2 and CX3CL1, was observed in aged hens than in young hens. A significantly higher number of macrophages and CD8+ T cells were observed in the uterine tissue of aged hens than in young hens. Furthermore, the expression of adhesion molecules associated with leukocytic infiltration was found to be higher in aged hens than in young hens. We conclude that the eggshell formation process may be affected by the pro- and anti-inflammatory cytokines and chemokines. The balanced expressions of these molecules might be disrupted in aged hens.

Short periods of incubation, egg turning during storage and broiler breeder hens age for early development of embryos, hatching results, chicks quality and juvenile growth

An effect of modification of storage conditions of the eggs of broiler breeder flocks at the age of 49-, 52- and 70-, 73-wks of life on an early embryonic development, hatching time and synchronization, hatchability rates, chicks quality and broiler growth was investigated. The eggs were divided into 4 experimental groups: COI = eggs storage 5 d, at turning every 12h; NSP = eggs storage 12 d, at turning every 12h; SPIDES = were treated with 4h pre-incubation at 30°C and 50-55% air humidity, delivered at 5 and 10 d over of 12 d of storage, and turning every 12h; NCOI = eggs storage 12 d, no turning and no pre-incubation. Eggs from older hens were characterized by poorer hatchability and poorer chicks quality. The use of 2 × 4h pre-incubation in 12 d of eggs storage could have an effect on the initial acceleration of embryonic development in eggs of young hens, contributing to the alignment of embryos development in eggs from young and older hens to 72h of incubation. Pre-incubation had no effect on the length of incubation period, hatching window, but it increased the hatchability of the set and apparently fertilized eggs and decreased the number of eggs not hatched, and also improved chicks quality. Eggs turning by 90° every 12h during the storage positively affected the embryonic development, shortening the incubation time and the quality of chicks, but had no effect on hatchability rates and body weight in 42 d of life. Based on the obtained results, it can be concluded that the applied modifications can be effective in counteracting the negative effects of storage of hatching eggs from both young and older birds.

The Impact of Bacillus subtilis KATMIRA1933 Supplementation on Telomere Length and Mitochondrial DNA Damage of Laying Hens.

In the current study, we performed in vivo investigation of probiotic intake influence on nuclear and mitochondrial DNA damage of hens, using quantitative PCR techniques. The probiotic supplementation to the diet of Hisex Brown hens had no significant effect on the rate of telomere shortening. After prolonged probiotic intake (225 and 445days), the 18-21% decrease in the mtDNA lesions was detected. Since avian mitochondrial DNA damage investigations are rare, the current study of the probiotic-enriched diet's impact on the damage of the hen mitochondrial DNA is novel and highly important. The decrease of mtDNA damage is a beneficial property, which could positively affect the reproductive aging of hens. The positive impact of probiotic supplementation on hens' performance traits such as hen-day egg production, egg weight and mass, and feed conversion ratio was observed.

Hen genetic strain and extended cold storage influence on physical egg quality from cage-free aviary housing system

In the United States, there is an increase in need for cage-free eggs in retail and food manufacturing sectors. Understanding the impact of cage-free systems and the corresponding management on egg quality is pertinent as the U.S. industry adapts existing housing and builds new cage-free housing structures. A study was conducted comparing 2 brown shell and 2 white shell hen strains housed in a cage-free aviary system. Each set of eggs were placed in cold storage and assessed at 0, 2, 4, 8, and 12 wk. Eggs were collected at 21, 31, 42, and 60 wk of hen age. A full profile of physical quality measurements was conducted on up to 18 intact eggs for each hen strain/egg storage/hen age combination. Egg weight increased approximately 10g for brown shell and 14g for white shell eggs as hens aged. Many of the properties monitored were significantly impacted by all 3 main effects (hen strain, egg storage, and hen age) resulting in 3-way interactions. A brown and a white shell strain had stronger shells (44N; P <0.0001) than the remaining brown and white shell strains (42N and 39N, respectively). The current study also determined volume of shell, total length, maximum width, and percent length at maximum width to more accurately indicate egg shape than shape index. One brown shell strain produced eggs with the most consistent shape characteristics over the hen ages monitored. White shell eggs from the cage-free aviary housing produced the highest whole-egg total solids between 31 to 60 wk of hen age, whereas brown shell eggs resulted in the most consistent level of whole-egg total solids (22-23.5%). The brown and white shell strains in the current study produce cage-free aviary eggs with distinctive physical quality attributes. The outcomes from this study can be utilized by the U.S. egg industry in planning management strategies and market placement of cage-free eggs.

Brown eggshell fading with layer ageing: dynamic change in the content of protoporphyrin IX.

The dynamic change in brown eggshell color as hens age has been observed, but much uncertainty still exists. We aimed to analyze the depth of eggshell color and quantity of protoporphyrin ΙΧ throughout the laying period to explore the reasons for color variation. In this study, 120 Rhode Island Red hens were used, and two eggs were collected from each individual at 26, 34, 42, 50, 60, and 70 wk of age. The eggshell color (L*, a*, b*), egg weight, eggshell dry weight, and protoporphyrin ΙΧ quantity in eggshell were measured for individual eggs. Our results showed that the intensity of brown eggshell color weaken as hens aged from 26 to 60 wk of age (L* gradually increased from 61.43 to 68.07), while eggshell lightness recovered slightly at 70 wk (L* = 64.77). The correlation analysis indicated that the content of protoporphyrin ΙΧ deposited in the eggshell was an important factor for lightness fading with the ageing process (the average r was 0.66, P < 0.01), while the egg weight had little impact on the eggshell color (the average r was 0.07, P > 0.05). The shade of the eggshell color (L* and a*) at the early laying period (26 or 34 wk) had a low correlation with the other age points (42, 50, 60, and 70 wk). However, high correlations between the shell color at 42 wk of age and subsequent ages (50, 60, and 70 wk) were found, suggesting that the intensity of eggshell color is more stable after egg-laying peaks (such as 42 wk of age). In conclusion, the intensity of brown eggshell color varies greatly among the whole laying cycle and breeders can choose the proper age for eggshell color measurements to ensure the degree of shell color in the late laying period.

Feed particle selection and nutrient intake altered by pecking stone consumption and beak length in free-range laying hens

The present study investigated the effects of pecking stones on feeding behaviour of hens from 16 to 46 weeks of age. Eighteen flocks of Hy-Line Brown hens were housed in 2 commercial free-range housing systems. Farm A housed 10 flocks of beak trimmed (infrared beak treatment) hens in fixed sheds. Farm B housed 8 flocks of hens with intact beaks in mobile sheds. On each farm, flocks were equally assigned to control groups (no access to pecking stones) and treatment groups (access to pecking stones). Data were evaluated every 10 weeks. At each time point, 10 hens per flock were housed in individual pens, and each hen was provided with 250 g of mash diet and ad libitum water for 24 h. After 24 h, feed samples were collected and used to determine 24-h feed intake. Nutrient and particle selection was measured by subtracting nutrients and particles present in the leftover feed from the vaules obtained in the offered feed and expressed the change (Δ). In addition, pecking stone consumption was recorded for each flock. Data were analysed separately for each farm using fixed effects of pecking stone availability and hen age. Spearman's rho correlation coefficients and linear regression models were constructed to evaluate the relationship of beak length and pecking stone usage, discrete mean particle size (dMEAN) consumption (Δ dMEAN), and Δ nutrient intake. Hens with access to pecking stones consumed significantly lower quantities of large feed particles (>2.8 mm) on farm A (P = 0.029) and selected significantly more fine particles, on farm B (P = 0.013). Overall, positive relationships (P = 0.001) between beak length and pecking stone consumption, Δ dMEAN, and Δ phosphorus consumption were observed. In conclusion, pecking stone consumption resulted in reduced selection and consumption of feed particles in hens housed on both farms. Further research is warranted to investigate the effect of pecking stones on sensory innervation of the beak.

Radiographic examination of keel bone damage in living laying hens of different strains kept in two housing systems.

A high prevalence of deviations and fractures of the keel bone is a widespread welfare problem in laying hens. The aim of this study was to experimentally investigate this multifactorial problem throughout the laying period and to compare the prevalence and severity in different layer lines and different housing systems. High performing white (WLA) and brown (BLA) pure bred layer lines and low performing white (R11, G11) and brown layer lines (L68) were kept in both single cages and a floor housing system. A total of 97 hens (19 or 20 from each line, respectively) were repeatedly radiographed in the 35th, 51st and 72nd week of age. Fracture prevalence increased with age (p<0.001). The proportion of deviated keel bone area increased only for caged BLA, WLA and R11 hens (p<0.05) and was significantly higher for caged WLA and R11 hens compared to floor-housed WLA and R11 hens in the 72nd week of age (p<0.05). In the 72nd week of age hens in the floor housing system showed significantly more fractures than hens kept in cages (p<0.05). Prevalence of keel bone deviations was significantly higher in the white layer line R11 but significantly lower in the white layer line G11 compared to both brown layer lines and WLA (p<0.05). Brown layers showed significantly more fractures than white layers (p<0.05) in the 51st and 72nd week of age. Within the brown layers there was a significantly lower prevalence of deviations (p<0.05) and fractures (p<0.05) in the low performing (L68) compared to the high performing line (BLA). Our results show a different development of keel bone damage in caged compared to floor-housed hens under experimental conditions. Additionally, they indicate genetic effects on keel bone damage.

Mineral content of eggs differs with hen strain, age, and rearing environment

Egg nutrient quality is strongly influenced by hen diet but is also affected by rearing environment, hen strain, and hen age. The objective of the current study was to determine the effect of: 1) conventional battery cages, 2) enrichable cage systems, 3) enriched colony housing, 4) cage-free, and 5) free-range rearing systems on mineral concentrations of whole, dried egg (yolk and albumen combined) from TA Tetra White (TW) and Hy-Line Brown (HB) hens at 44, 68, and 88 wk of age. We hypothesized that mineral concentration of eggs would differ among rearing systems but not between strains or with hen age. Hens held in enriched colony housing systems produced eggs with 10% lower Mg and 11% lower Mn levels than conventional hens. Concentrations of Ca and Cu were higher (7 and 8%, respectively) in eggs from TW hens than from HB hens. Eggs from HB hens had 8% higher concentrations of Fe, 6% higher Mg and 5% higher Mn than TW hens. Mn was higher in eggs from 44-wk hens than from 68- or 88-wk hens (16 and 11%, respectively). Interaction effects between rearing environment and hen age were observed for K and Mn concentrations. Eggs from 68-wk hens in conventional rearing systems contained 14 to 21% more K than eggs from conventional hens at 44- and 88 wk and 14 to 18% more than eggs from 68-wk hens in other rearing systems. At 88 wk of age, hens in conventional rearing systems produced eggs with higher Mn concentration than hens in enrichable or enriched colony housing systems (22 and 23%, respectively). Interactions between rearing environment, hen strain, and hen age were observed for egg Zn levels among 44- and 68-wk hens but were not detectable among 88-wk hens regardless of rearing system or hen strain. Observed differences in egg mineral content in our study were small and are unlikely to have substantial impact on human nutrition.

Variability and interaction of some egg physical and eggshell quality attributes during the entire laying hen cycle

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.

The Effect of the Type of Alternative Housing System, Genotype and Age of Laying Hens on Egg Quality

Abstract The present study investigated the effect of the type of alternative housing system, and genotype and age of laying hens on physical traits of egg shell and contents. It was demonstrated that alternative housing system type influenced egg weight and shape, and eggshell color and yolk color intensity. Eggs from free-range system were heavier and were characterized by more intense yolk color. No effect of alternative housing system type on albumen height, value of Haugh units (HU value) and presence of meat and blood spots was noted. Hen genotype had a significant effect on egg weight and eggshell color intensity in each of the alternative housing systems tested in this study. Hy-line Brown hens laid heavier eggs than hens of native breeds. Genotype was also observed to affect egg content traits (albumen height, HU values and presence of meat and blood spots). Independently of the type of alternative housing system, most blood and meat spots were noted in eggs of hens laying brown-shelled eggs, i.e. R-11 and Hy-line Brown layers. Laying hen age significantly impacted on egg weight, yolk percentage, eggshell traits (color intensity, weight, thickness and strength) and egg content traits (HU value, yolk weight and color intensity, presence of meat and blood spots). Older hens laid heavier eggs with a greater yolk percentage but with thinner eggshell.

Age-related changes of yolk precursor formation in the liver of laying hens

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 (P<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.

Genome-Wide Association Analysis of Age-Dependent Egg Weights in Chickens.

Egg weight (EW) is an economically-important trait and displays a consecutive increase with the hen's age. Because extremely large eggs cause a range of problems in the poultry industry, we performed a genome-wide association study (GWAS) in order to identify genomic variations that are associated with EW. We utilized the Affymetrix 600 K high density SNP array in a population of 1,078 hens at seven time points from day at first egg to 80 weeks age (EW80). Results reveal that a 90 Kb genomic region (169.42 Mb ~ 169.51 Mb) in GGA1 is significantly associated with EW36 and is also potentially associated with egg weight at 28, 56, and 66 week of age. The leading SNP could account for 3.66% of the phenotypic variation, while two promising genes (DLEU7 and MIR15A) can be mapped to this narrow significant region and may affect EW in a pleiotropic manner. In addition, one gene (CECR2 on GGA1) and two genes (MEIS1 and SPRED2 on GGA3), which involved in the processes of embryogenesis and organogenesis, were also considered to be candidates related to first egg weight (FEW) and EW56, respectively. Findings in our study could provide worthy theoretical basis to generate eggs of ideal size based on marker assisted breeding selection.

Cuticle and pore plug properties in the table egg

Food safety of table eggs is vital since many pathogens can contaminate the unfertilized egg, leading to increased risk of foodborne illness for consumers. The eggshell cuticle is the first line of defense to restrict the entry of egg-associated pathogens, such as Salmonella Enteritidis. The thickness and completeness of coverage of the cuticle layer are heritable traits that are strongly associated with egg resistance to bacterial penetration. The present study characterizes the chemical composition of the eggshell cuticle and structure of pore plugs from table eggs. Eggs collected from both brown and white egg laying Lohmann flocks (early, mid, and late lay) were either unwashed or washed. Pore plugs were characterized using scanning electron microscopy (SEM), and elemental composition was determined using energy-dispersive x-ray spectroscopy (EDS). SEM observations confirmed that the plug formed by the cuticle layer within the eggshell pore remains firmly lodged throughout the commercial washing process. The eggshell thickness and cuticle pore length visualized in brown eggs was significantly higher than in white eggs in hens of all ages. EDS analysis revealed that the pore inner surface was enriched in phosphorus and chemically different from the surrounding bulk eggshell mineral. Detailed assessment of the cuticle chemical composition was performed by Fourier transform infrared spectroscopy (FTIR). Washing of eggs removed cuticle from the eggshell surface. There was a trend of lower cuticle coverage with increasing hen age for white eggs. A significant reduction in the amount of proteins and phosphates and polysaccharides was observed in the cuticle of brown unwashed eggs with hen age. In white unwashed eggs, amides and lipids decreased with hen age; by contrast, the amount of sulfate was highest at mid-lay. The results from our research will assist selective breeding programs that target cuticle integrity and pore plug stability to enhance egg resistance to pathogen penetration and improve food safety.

Effects of maternal dietary canthaxanthin and 25-hydroxycholecalciferol supplementation on antioxidant status and calcium-phosphate metabolism of progeny ducks

Three experiments were conducted to investigate the effects of maternal dietary canthaxanthin (CX) and 25-hydroxycholecalciferol (25-OH-D3) supplementation on antioxidant status and calcium-phosphate metabolism of progeny ducks. Cherry Valley duck breeders (38 wk old) were fed either a control diet or the same diet plus CX (6mg/kg) and 25-OH-D3 (0.069mg/kg) for 32 weeks. Experiments 1, 2, and 3 were conducted with progeny ducks hatched from eggs laid by duck breeder hens at 54, 62, and 70 wk of age, respectively. Progeny ducks from both maternal treatments were fed with the same NRC (1994) vitamin regimen starter (1 to 14 d) and finisher (15 to 35 d) diets in experiments 1 and 2, and fed with the same high vitamin regimen starter (1 to 14 d) and finisher (15 to 35 d) diets in experiments 3. High vitamin regimen had higher levels of all vitamins, except biotin, than the NRC (1994) vitamin regimen. In experiment 1, maternal CX and 25-OH-D3 increased (P < 0.05) shank pigmentation and tibiotarsus ash and tended to decrease (P < 0.1) liver total superoxide dismutase activity (T-SOD) of one-day-old progeny ducks; and increased (P < 0.05) shank pigmentation, decreased (P = 0.05) liver protein carbonyl, and tended to increase (P < 0.1) liver total antioxidant capacity (T-AOC) of 14-day-old progeny ducks. In experiment 2, maternal CX and 25-OH-D3 increased (P < 0.05) shank pigmentation and liver T-AOC and decreased (P < 0.05) liver protein carbonyl of one-day-old progeny ducks, but increased (P < 0.05) the serum phosphate level of 14-day-old progeny ducks. In experiment 3, maternal CX and 25-OH-D3 increased (P < 0.05) shank pigmentation of one-, 14-, and 35-day-old progeny ducks and tended to increase (P < 0.1) liver T-SOD and tibiotarsus ash, but decrease (P < 0.1) liver malondialdehyde of one-day-old progeny ducks. It can be concluded that progeny dietary high vitamin regimen could partially prevent maternal CX-derived progeny shank pigmentation from bleaching. Maternal CX- and 25-OH-D3-derived effects are influenced by the hen's age and progeny's dietary vitamin regimen.

Factors affecting fertility, hatchability and chick survivability of Vanaraja birds under intensive rearing in sub-temperate condition

The study was conducted to determine the effect of various factors viz. season, age of hen, egg weight and source of egg on reproductive performance of Vanaraja birds at an altitude of 1300 m at mean sea level in Sikkim. Fertility rate during summer was significantly higher than spring and winter. Fertility rate was significantly higher from 41 to 50 age of week as compared to 51 weeks onwards. Significantly higher fertility rate was observed in medium size egg as compared to other groups. The fertility rate of eggs produced in the farmers field were significantly lower than at farm. Hatchability on fertile egg set was highest during spring followed by summer while it was significantly lower during winter. Significantly higher hatchability was observed in age of 26 to 40 weeks compared to 51–60 and 61–70 weeks of age. Also, significantly higher hatchability was observed in medium size egg group than the other two groups. Chick weight on day of hatching was significantly higher in summer compared to autumn and winter. Egg weight also significantly affects chick weight which was highest in medium size egg. Significantly higher chick’s survivability was recorded in summer, spring and autumn season as compared to winter. Although, season, age of hen, egg weight and source of egg affected the production performance of Vanaraja birds, but it can be reared successfully throughout the year for production purpose.

PERFORMA AYAM RAS PETELUR COKLAT DENGAN FREKUENSI PEMBERIAN RANSUM YANG BERBEDA

This aims of the study is to determine the effect of different feeding frequency on layer performance (feed intake, hen day production, egg weight, and feed conversion ration) Data experiment were held on 10th April-10th July 2017 at Abas Farm, Ponggok subdistric, Blitar regency. Four hundred laying hens of ISA Brown strain age 30 weeks were used in this study and kept in individual cages. A randomized completely design was applied with 4 treatments and 5 replications. The treatment consists of P0: 2 times feeding, P1: 3 times feeding, P2: 4 times feeding, and P3: 4 times feeding. Data ware analyzed using analysis of variance at 5% level and Duncan test at 5 % level. The conclusion based on the result were: the treatments not significant (P&gt;0.05) on feed intake, egg weight, and feed conversion ration, but significant (p&lt;0.05) on hen day production. It’s suggested to use 2 or 3 time feeding frequency.Keyword: feeding frequency, performance, layer.

PERFORMA AYAM RAS PETELUR COKLAT DENGAN FREKUENSI PEMBERIAN RANSUM YANG BERBEDA

This aims of the study is to determine the effect of different feeding frequency on layer performance (feed intake, hen day production, egg weight, and feed conversion ration) Data experiment were held on 10th April-10th July 2017 at Abas Farm, Ponggok subdistric, Blitar regency. Four hundred laying hens of ISA Brown strain age 30 weeks were used in this study and kept in individual cages. A randomized completely design was applied with 4 treatments and 5 replications. The treatment consists of P0: 2 times feeding, P1: 3 times feeding, P2: 4 times feeding, and P3: 4 times feeding. Data ware analyzed using analysis of variance at 5% level and Duncan test at 5 % level. The conclusion based on the result were: the treatments not significant (P&gt;0.05) on feed intake, egg weight, and feed conversion ration, but significant (p&lt;0.05) on hen day production. It ’s suggested to use 2 or 3 time feeding frequency.Keyword: feeding frequency, performance, layer.

Dietary tea polyphenol supplementation improved egg production performance, albumen quality, and magnum morphology of Hy-Line Brown hens during the late laying period.

The aim of this study was to investigate how dietary supplementation of tea polyphenols (TP) and tea catechins (TC) affect laying performance, albumen quality, ovomucin composition, and magnum morphology of laying hens in the late phase of production. Two hundred seventy Hy-Line Brown laying hens (64 wk old) were assigned to a basal diet (the control), the basal diet supplemented with 200 mg/kg tea polyphenols (TP200) or 200 mg/kg tea catechins (TC200). Each treatment had 6 replicates with 15 hens each. The feeding trial lasted 10 wks. Over the course of the trial, dietary supplementation with TP200 significantly increased the egg production (EP) and improved the feed conversion ratio (FCR) in wk 6 to 10 and wk 1 to 10 (P < 0.05). The albumen height and the Haugh unit (HU) of hens fed TP200 were higher than those of hens fed the control diet at wks 8 and 10 (P < 0.05). However, there were no significant differences in the albumen height and the HU between the TP200 and TC200 groups (P > 0.05). The SDS-PAGE analysis indicated that bands of the ovomucin fractions in the TP200 group had the highest intensity compared with those of the control and TC200 groups. Compared with the control, there was a significant increase in protein sulfhydryl (SH) content of the albumen in the TP200 group at the end of experiment, while a significant decrease in protein carbonyl content and protein surface hydrophobicity (P < 0.05). There were also obvious increase in the height and width of the primary folds, epithelial cell height, and cilia height of the simple columnar epithelium in the TP200 group compared with the control and TC200 groups (P < 0.05). In conclusion, dietary supplementation with 200 mg/kg TP can improve performance, albumen quality, and magnum morphology of aged hens. In addition, TP rather than TC could improve the health status of the magnum for aged layers.

Effect of housing system and age of laying hens on eggshell quality, microbial contamination, and penetration of microorganisms into eggs

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 cm&lt;sup&gt;2 &lt;/sup&gt;per hen vs free range: 60 hens, 9 hens per m&lt;sup&gt;2&lt;/sup&gt;) 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 &amp;lt; 0.001, 4.51 vs 2.75 log cfu/eggshell) and Enterococcus (P &amp;lt; 0.001, 2.56 vs 1.11 log cfu/eggshell), and the total number of microorganisms (P &amp;lt; 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 &amp;lt; 0.001, 4.23 vs 2.91 log cfu/eggshell) and Enterococcus (P &amp;lt; 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.