Body Weight Of Hens Research Articles

The Impact of Lighting Regimen and Feeding Program during Rearing on Hy-Line Brown Pullets at the End of Rearing and during Early Lay

As hen body weight (BW) impacts egg weight (EW) and feed efficiency, egg producers prefer pullets of a specific size to enter the egg-laying cycle. Lighting and feeding programs were tested to achieve target Hy-Line Brown pullet BW. Three feeding programs were implemented: ad libitum (ad lib); feeding to achieve breed standard weight for age (BSW); and feeding to achieve 88% BSW (managed). The feeding programs were used with either control lighting (CL: 10 h light/d from 7 weeks of age (WOA)) or reduced lighting (RL: 9 h light/d from 4 WOA). One-hundred and fifty pullets were assigned to each feeding program by lighting treatment during rearing. At 16 WOA, 70 pullets from each treatment during rearing were moved to cages and onto ad libitum feeding under a step-up photoperiod reaching 16 h light/d at 33 WOA. The age and weight of the first egg, hen BW, feed intake (FI), egg production (EP), and EW were measured until 36 WOA. At 16 WOA, pullets reared with ad lib feeding under CL had higher BW and cumulative FI (CFI) compared to ad lib feeding under RL. The latter were the earliest to lay, and the managed pullets under CL were the last to lay. Control lighting and BSW independently generated the heaviest first eggs. At 36 WOA, BW, EW, CFI, and cumulative egg production (CEP) were highest following ad lib feeding during rearing, while rearing under CL generated higher BW and EW but lower CEP than RL. Hence, lighting and feeding programs throughout rearing can regulate pullet growth, FI, and hen performance throughout early lay.

Study on the changing patterns of production performance of laying hens and their relationships with environmental factors in a large-scale henhouse

The production performance of laying hens is influenced by various environmental factors within the henhouse. The intricate interactions among these factors make the impact process highly complicated. The exact relationships between production performance and environmental variables are still not well understood. In this study, we measured the production performance of laying hens and various environmental variables across different parts of the henhouse, evaluated the weight of each environmental variable, and constructed a laying rate prediction model. Results displayed that body weight, laying rate, egg weight and eggshell thickness of hens decrease gradually from WCA to FA (P < 0.05). Serum levels of FSH and LH, as well as antibody level of H5 Re-13, gradually decrease from WCA to FA (P < 0.05). Moreover, the values for temperature (T), temperature-humidity index (THI), air velocity (AV), carbon dioxide (CO2), and particulate matter (PM2.5) gradually increase from WCA to FA (P < 0.05). Conversely, the relative humidity (RH) value gradually decreases from FA to WCA (P < 0.05). Additionally, the weights of the environmental variables, determined using a combination of the grey relational analysis (GRA) and analytic hierarchy process (AHP), were as follows in descending order: RH, THI, T, light intensity (LI), AV, PM2.5, NH3, and CO2. When the number of decision trees in the laying rate prediction model was set to 2,500, the results displayed a high level of agreement between the model's predictions and the observed outcomes. The model's performance evaluation yielded an R2 value of 0.89995 for the test set, suggesting strong predictive effects. In conclusion, the current study revealed significant differences in both the production performance of laying hens and the environmental variables across different parts of the henhouse. Furthermore, the study demonstrated that different environmental factors have distinct impacts on laying rate, with humidity and temperature identified as the primary factors. Finally, a multi-variable prediction model was constructed, exhibiting high accuracy in predicting laying rate.

Comparative efficacy of hydroxychloride and organic sources of zinc, copper, and manganese on egg production and concentration of trace minerals in eggs, plasma, and excreta in female broiler breeders from 42 to 63 weeks of age

Comparative efficacy of hydroxychloride (HC) and organic (OR) sources of Zn, Cu and Mn on performance of broiler breeders (BB) between 42 and 63 weeks of age (WOA) was investigated. A total of 408 ♀ Ross 708 and 48 ♂ Yield Plus cockerels were placed in pens (17 ♀ and 2 ♂) housed in 2 rooms (12 pens/room) and allocated to one of 2 diets in a completely randomized block design (n=12). The diets had similar nutrient specifications but differed in Zn, Cu, and Mn sources: 1) HO, a blend of 80% HC and 20% OR sources, and 2) OR, 100% OR sources. Birds were fed and managed according to breeder guidelines. The egg count was recorded daily and categorized as normal or abnormal. Egg yolk color, albumen height, Haugh unit, eggshell thickness, and eggshell breaking strength were assessed every 4 wk. Individual hen body weight (BW) was recorded at 5-wk intervals to determine BW uniformity. At 52 and 63 WOA, the eggs and excreta samples were collected. At the end of the trial, 4 hens per pen were bled for plasma concentration of trace minerals and organs (liver, gizzard, spleen, kidney, and thymus) weight. There were no interactions between source and age on any parameters (P > 0.05). There were no main effects of source on egg production, eggshell quality, BW, and organs weight (P > 0.05). Hens fed HO diets had darker yolk compared to those fed OR diets (P = 0.014). The concentration of Zn in the eggs of OR BB was higher (P = 0.022) than for HO birds. However, there were no dietary effects on the concentration of trace minerals in the egg, plasma, and excreta (P > 0.05). The results indicated that a mixture of HC and O as sources for Zn, Cu, and Mn was as effective as OR sources in supporting egg production, egg quality, and trace mineral utilization in broiler breeders.

Optimizing Local Chicken Productivity in a Semi-Intensive System in the Sepakat Jaya Livestock Group, Padang Laweh Village, Kampar District

The productivity of local chickens can be improved through the enhancement of the rearing system, ranging from extensive to intensive management. This research aims to identify the production characteristics of native chickens reared semi-intensively in the Sepakat Jaya Livestock Group, Padang Laweh Village. Ten farmers who raise more than 20 local chickens were selected as respondents for this study. The research was conducted in the form of a survey, with the selection of the location, farmers as respondents, and the use of native chickens as research samples carried out through purposive sampling. The collected data, such as the age at first egg laying, the body weight of the hens at first egg laying, and the weight of the first egg, were analyzed using descriptive statistics. The results of this study indicate that the production characteristics of local chickens reared semi-intensively in the Sepakat Jaya, Padang Laweh, include age at first egg laying of approximately 178.7 days, a body weight of hens at first egg laying of around 1.46 kg per bird, and a weight of the first egg of about 49.1 grams per egg. This research concludes that semi-intensive rearing can improve the production characteristics of local chickens in the Sepakat Jaya, Padang Laweh.

Spatial distribution, movement, body damage, and feather condition of laying hens in a multi-tier system

The welfare and health of laying hens in the multitier system raise concern in public. The flock distributions during feeding time at 51 and 89 wk were studied in a multitier system. Furthermore, the ultra-high frequency radio frequency identification (UHF RFID) equipment was used to identify the transition between tiers and time spent in each tier of 48 focal hens (12 hens from each tier-group of the multitier system) at 92 wk of age. The body weight, tibia size (length and width), body damage (comb and rear part), and feather condition (neck, breast, back, tail, cloaca, and wings) of focal hens from different tier-groups were further compared. The results showed that the spatial distribution in flocks changed from top to bottom with increasing age. The hens at 51 wk of age were mainly distributed in the 4th tier (19.6 ± 5.0% in 1st tier, 9.6 ± 1.1% in 2nd tier, 23.6 ± 2.9% in 3rd tier and 47.3 ± 2.6% in 4th tier), and hens at 89 wk of age were mainly distributed in the lower tiers (33.5 ± 1.5% in 1st tier, 31.9 ± 5.1% in 2nd tier, 15.7 ± 3.4% in 3rd tier and 16.6 ± 3.1% in 4th tier). The spatial distribution of hens at 89 wk of age was more even than that at 51 wk of age. At 92 wk of age, the proportion of time spent in original tier of 4 tier-groups was 91.0 ± 5.7%, 51.9 ± 5.7%, 59.0 ± 7.0% and 63.0 ± 6.7%, respectively. Focal hens preferred to stay in the original tier and spent significantly less time in other tiers (P < 0.05). There was no significant difference in body weight, body damage score, tibia width and partial feather scores (neck, breast, tail, and cloaca) of focal hens among 4 tier-groups (P > 0.05). However, focal hens from 1st tier had worse feather scores on wings and back, and shorter tibia length compared to other tiers suggesting that there were more lower ranking birds that located in lower tier to avoid competition, but had equal access to resource, which is good for their welfare and health. In summary, the overcrowding situation was improved near the end of the laying cycle in the multitier system, thereby mitigating the potential negative effects to the lower ranking hens and maintain a satisfactory level of welfare and health for laying hens near the end of the laying cycle.

Estimating energy utilization in laying hens: what are the best response criteria?

An experiment was conducted to evaluate the effects of varying dietary energy on the performance and energy storage in laying hens from 36 to 52 wk of age. A total of 252 Hy-Line W-36 laying hens were housed in cages with 3 birds per cage and 12 replicate cages per treatment. Birds were control fed 1 of 7 experimental diets ranging in dietary energy from 2,750 to 3,050 kcal/kg with a 50 kcal/kg difference among each of the diets. Egg production, energy intake, feed intake, egg weight, egg mass, and feed efficiency were calculated every 2 wk so that performance data could be analyzed every 2 wk using repeated measures analysis. Hens were weighed every 4 wk for repeated measures analysis and carcass total, lean, and fat mass were determined at 52 wk using dual X-ray absorptiometry. Correlations between dietary energy and energy intake with performance parameters, and body composition were generated. Dietary energy (kcal/kg) was significantly correlated with all performance parameters except hen housed egg production (HHEP; P = 0.07) and lean carcass mass (P = 0.60). For dietary energy, the highest correlations were total carcass mass (r = 0.60) and carcass fat mass (r = 0.54). Energy intake (kcal/d) was significantly correlated with all performance parameters except feed intake (P = 0.18). The highest correlations were between energy intake and total carcass mass (r = 0.63) or body weight (r = 0.51). These results suggest that dietary energy has a more pronounced effect on body mass and fatty tissue over the short run (16-wk period) before direct performance responses are observed. Therefore, hen body weight and composition can be used as a more sensitive measurement of shorter-term hen energy status than egg production or feed efficiency.

Association of feed efficiency with organ characteristics and fatty liver haemorrhagic syndrome in laying hens

Poor feed efficiency (FE) in hens impacts body weight (BW) and may reflect suboptimal health. Fatty Liver Haemorrhagic Syndrome (FLHS) is mostly observed in laying hens and affects egg production and hen performance. The aim of this study was to investigate the relationships of FE and BW with organ characteristics, liver composition and incidence of FLHS of 150 individually housed ISA Brown hens ranked on the basis of feed conversion ratio (FCR) attained from early lay. At 45 weeks, 10 birds per FE group (HFE—High feed efficient; MFE—medium feed efficient; LFE—low feed efficient) were randomly selected and euthanized. Hen BW was positively associated with feed intake and FCR. The HFE hens had a lower abdominal fat pad and liver weight compared to LFE hens. FLHS lesion score was higher (worse) in the LFE than HFE hen group and was moderately positively associated with BW and abdominal fat pad, but strongly positively associated with liver weight. Liver pathology of LFE hens showed hepatocytes with abnormal retention of lipids causing distended cytoplasmic vacuoles compared to the HFE hens. Hens which exhibited poorer FE in early lay had heavier abdominal fat pads, heavier, fatter livers and were more prone to FLHS.

Minimal effects of ultraviolet light supplementation on egg production, egg and bone quality, and health during early lay of laying hens.

Chicken vision is sensitive to ultraviolet (UV) light containing the UVA spectrum, while UVB plays a key role in the endogenous production of vitamin D3. However, commercially available light sources are typically deficient in the UV spectrum and thus may not adequately fulfill the lighting requirements of indoor-housed laying hens. We hypothesized that supplementary UVB light may improve egg production and egg quality, and bone health during early lay relative to UVA supplementation or standard control lighting. To investigate the effects of UV light supplementation, an experiment was conducted on 252 ISA Brown hens during 16 to 27 weeks of age. Birds were housed in eighteen pens (14 hens/pen) under three different light treatment groups each with six replications: (i) UVO: standard control lighting with LED white light, (ii) UVA: control lighting plus supplemental daylight with an avian bulb, and (iii) UVA/B: control lighting plus a supplemental full spectrum reptile bulb containing both UVA and UVB wavelengths. Hen-day egg production and egg quality, blood parameters including plasma Ca and P, and serum 25(OH)D3, and hen body weight and external health scoring were measured at different age points; while bone quality was assessed at the end of the experiment at 27 weeks. Data were analyzed in JMP® 16.0 using general linear mixed models with α level set at 0.05. Results showed that UVA and UVA/B supplemented birds reached sexual maturity (50% production) 3 and 1 day earlier, respectively, than control birds. There was a trend for UV lights to increase hen-day egg production (P=0.06). Among egg quality traits, only eggshell reflectivity and yolk index were affected by UV lights (P=0.02 and 0.01, respectively); however, most of the egg quality traits changed over age (all P<0.01). Post-hoc tests showed higher serum 25(OH)D3 in the UVA/B group relative to control hens (P<0.05); but there was no treatment effect on plasma Ca and P or on bone quality parameters (all P>0.05). A significant interaction was observed between light treatment and age for the number of comb wounds (P=0.0004), with the UV supplemented hens showing more comb wounds after 24 weeks. These results demonstrated that supplemental UVA/B light had minimal effects on egg production and egg quality, whereas, UVA/B exposure may increase vitamin D3 synthesis during the early laying period. The optimum duration of exposure and level of intensity needs to be determined to ensure these benefits.

Effects of keel bone deviation on post-peak egg production in a commercial laying hen flock with different breast condition

This study was made to investigate the effects of breast condition and keel bone deviations on post-peak egg production of a commercial laying hen housed in a multi-tier conventional battery cage. The birds divided into two groups according to presence of keel bone deviation at first. Then the birds further divided into two groups according to breast condition as well developed or relatively well developed. The laying hens were kept under identical management conditions for commercial laying hens during the study. Data about daily egg production, feed intake, mortality and egg weight was collected from 62 to 77 weeks of age in the groups. There were no significant effects of keel bone deviation on body weight and egg weight of the layer hens. The initial and final body weight of the birds are significantly different between the breast condition groups (P

The role of hen body weight and diet nutrient density in an extended laying cycle

The egg production (EP), egg quality and health of heavier or lighter hens fed a diet of either higher nutrient density (HND) or lower nutrient density (LND) during early lay, was assessed at very late lay. Based on their body weight (BW) at 18 wk of age (WOA) ISA Brown pullets were allocated as either heavier weight (HW; average 1.65 kg) or lighter weight (LW: average 1.49 kg). Half of each BW group received the HND (2,901 kcal/kg; 17.6% crude protein (CP) or LND (2726 kcal/kg, 16.4% CP) diet from 18 to 24 WOA. From 25 to 90 WOA all birds received identical early, then mid and late-lay diets. Hen BW was measured after peak-lay (36 WOA) and at 90 WOA. At 89 WOA and across 18 to 36 and 18 to 89 WOA feed intake (FI), EP, egg mass (EM), and feed conversion ratio (FCR) were calculated. Eggshell quality, breast score, relative ovary weight and liver and bone health were evaluated in very late lay. Differences in BW continued to 90 WOA. At 36 WOA HW hens produced heavier eggs, and had higher 18 to 36 WOA cumulative FI, EM (P < 0.001) and FCR (P < 0.05). When 89 WOA HW birds consumed more feed (P < 0.001) but EP, EM and FCR did not differ from LW hens. Cumulatively, 18 to 89 WOA FI and EM were higher for HW hens (P < 0.05), but cumulative EP and FCR was not different. The early-lay HND diet improved very late lay eggshell thickness (P < 0.05) and shell breaking strength (P=0.05). Lighter hens fed HND and HW hens fed LND diet produced heavier eggs, higher relative oviduct weight and lower liver lipid peroxidase in very late lay (P < 0.05). Bone strength did not differ, but LW hens had higher femoral manganese and zinc (P < 0.05), lowering their likelihood of osteoporosis. Overall LW hens sustained EP throughout a longer laying cycle with beneficial bone characteristics. The HND diet improved eggshell strength and, in LW hens reduced hepatic oxidation.

Effects of different intermittent illumination patterns on production performance of slow growing type Yellow chickens

Abstract The objective of this study was to investigate the effects of intermittent illumination around noontime on the F line of slow growing line of Yellow chickens. The chickens were randomly divided into three groups of 70 roosters and 100 hens kept under three different illumination patterns. Group I was the control group (16 h of illumination at 10 lux). After day 21, in group II the light was additionally turned off during noon from 12:00–13:00 and in group III from 12:00–14:00 based on the lighting schedule of group I. The results showed that there was no significant difference in body weight (BW) between the three groups during the first 21 days ( p> 0.05). On day 42, BW of roosters and hens in group II was 35.2 g/21.7 g and 39.7 g/27.3 g higher than that of those in groups I and III ( p< 0.05), but there were no significant differences between group I and III ( p> 0.05). Oblique body length and shank length of group II were significantly higher than in groups I and III (p<0.05). After day 43, feed conversion ratio of group II was significantly higher than in groups I and III (p < 0.05). Comb perimeter, area and vertical area of group I were significantly higher than in groups II and III, and in group II these parameters were significantly higher than in group III (p<0.05). Slaughtering weight and breast muscle percentage of group II were significantly higher than in groups I and III, leg muscle percentage was significantly lower in group III ( p< 0.05) compared with the other groups. On day 84, there were no significant differences in blood indices (IGF-1, growth hormone, testosterone) or meat quality indices (flesh colour, shear force, PH, and water-holding capacity) between the three groups ( p> 0.05), but some indicators in group II showed an increasing trend. Based on these results, the intermittent light pattern of group II not only saved electrical energy and diet resources but also improved some indices of production performance.

Acute phase proteins, endocrine and productive responses of laying hens to heat stress

This study was designed to characterize changes in the acute phase proteins (APPs), hormones parallel to performance, and egg quality traits in laying hens exposed to heat stress (HS). A total of 120 sixteen-week-old Lohmann hens was allowed an adaptation period of 5 weeks in 3 different rooms at 21 °C. The hens were then exposed to one of three climatic thermal treatments over the next 6 weeks; thermoneutrality (TN, 21 °C), constant (C-HS, 28 °C), and cyclic HS (HS, 20 h/d at 28 ± 1 °C and 4 h/d at 33 ± 1 °C). Blood samples were weekly obtained, and serum levels of APPs [serum amyloid A (SAA), transferrin, and ovotransferrin], and hormones [leptin, triiodothyronine (T3), thyroxine (T4), and corticosterone] were measured. In addition, core body temperature (T$_{core}$), hen's body weight (BW), and egg quality parameters were recorded. Results indicated that SAA, transferrin, and ovotransferrin were not significantly (p > 0.05) different among the three thermal treatments in comparison with control; HS-hens had numerical increases of 2.46%, 3.46%, and 5.05% of the three APPs, respectively. Leptin levels were higher (p < 0.05), and T4 levels were lower (p < 0.05) in the HS than TN, meanwhile both C-HS and HS suppressed (p < 0.05) T3 levels in comparison with the TN. Furthermore, HS induced a significant variation (p < 0.05) in T$_{core}$ patterns, BW, eggs' number and weight, albumen height, and Haugh unit among the three thermal treatments. In conclusion, HS induced multiple changes in the APPs, hormones, performance, and egg quantity and quality parameters tested, and can potentially be used in future research as early biomarkers for stress in layers.

Growth Evaluation of Native Chicken on Different Type of Hen Body Weight

The aim of this research is to measure effect of hen body weight to the growth rate of native chicken. Ten native hens divided by two classifications (heavy and light body weight), 2 native roosters, 58 (from hen with heavy body weight) and 62 (from hen with light body weight) female day old chicks (DoC) use in this research. Hatching machine, communal cage, feeder tray, drinking jar, balance body weight and vernier calliper, were use in this research. Body weight and morphometric of female native chicken from DoC up to 10 week was measured. T-test analysis was used with help of SPSS 25. The results showed that the hen with heavy body weight resulted to the higher morphometric and body weight of female native chicken (P&lt;0.05) on 7 and 8 week, respectively. The growth rate gain of female native chicken hatched by the hen with heavy body weight is significantly difference (P&lt;0.05) on body weight. The conclusion is the hen with heavy body weight will result to the higher body weight and morphometric of female native chicken.

Effect of Phytase Supplementation on the Performance of Babcock-380 Layer Hens

In order to examine the effect of phytase supplementation in the diet of laying hen this experiment was conducted with 30 commercial hybrid Babcock-380 layers of 73 weeks of age. The hens were grouped into 3 treatment groups and given microbial phytase (Rena Phytase 400) at levels 2.5, 1.5 and 0 (control) g/kg feed in addition to their basal diet (110 g commercial pellet/day). Records on egg production/group/day, egg mass weight/day, body weight of hens at the end of experimental period were taken and analysed. Results revealed that hen house egg production (HHEP) and egg weight (EW) varied (p&lt;0.05) among the treatment groups but level of phytase did not affect (p&lt;0.05) body weight of hens. Both HHEP and EW were in order of 2.5&gt;1.5&gt;0 g/kg feed phytase group and all the means were significantly (p&lt;0.05) different from each other within treatment groups. Microbial phytase supplementation in layer ration proved to be beneficial in terms of egg production and egg size even after 72 weeks of age of hens. Layer farms in Malaysia can use this technology to earn more profit.

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Feed shortage had become a major factor constraining the development of animal husbandry. Forage canola has been found to be a potential feed crop due to its high yield and good quality. Therefore, this study mixed different proportions of forage canola to the diet of laying hens and all eggs were collected for analysis. Laying hens were divided into four groups according to the feeding amount of canola: 0 kg, 3 kg, 6 kg, 9 kg, with 30 laying hens in each group. In the feeding trial, there was no negative effect on hen body weight, egg production, or overall egg quality. The results showed that Group B, C and D complete feed consumption is less than Group A. From the spectrum analysis, the trend of the Group A was different from that of the other three groups. After 35 days of rearing, the laying rate of the Group B and the Group C increased about 30% compared to 1 to 7 day. The weight of the Group B and Group C increased about 5% compared with the initial period, while the Group A increased 0.6% and the Group D increased by 3%. The eggshell strength of the Group B and Group C also increased significantly. The contents of phosphorus and potassium in the Group B and C were higher than those in the Group A and Group D. The effects of canola to poultry diets is therefore of practical interest. This study will provide us a potential forage substance in laying hens production performance. © 2021 Friends Science Publishers

Dietary Soybean Oil Supplementation Affects Keel Bone Characters and Daily Feed Intake but Not Egg Production and Quality in Laying Hens Housed in Furnished Cages.

To evaluate dietary soybean oil supplementation on production performance, egg quality, and keel bone health in laying hens. Two hundred and four laying hens at 20 weeks of age (WOA) were distributed into 12 cages containing 17 birds each. Birds were either fed a commercial diet (control group, CON) or a diet supplemented with 3% of soybean oil (SO group). Experiments lasted 17 weeks. Body weight, daily feed intake, production performance and egg quality were measured at 25, 29, 33, and 37 WOA. Birds were subsequently assessed for keel bone status by palpation, and keel was excised to measure bone length, microstructure, bone mineral density (BMD), elements contents, and the expression of osteoprotegerin (OPG), receptor activator of nuclear factor kappa-B ligand (RANKL), collagen type II alpha 1 (COL2α1), periostin (POSTN), and sclerostin (SOST). The results showed that dietary SO supplementation did not affect production performance and egg quality (P > 0.05), but improved body weight of hens at 29 and 37 WOA (P < 0.05), and decreased daily feed intake at 33 and 37 WOA (P < 0.05). Incidence of keel bone damage (especially fracture) was higher in hens of SO group. Keel bone length in birds of SO group was significantly decreased compared to CON (P < 0.05). Keel bone of supplemented hens showed increased trabecular separation at 29 WOA and higher levels of V, Mn, Fe, Se, and Ba at 33 WOA (P < 0.05). Moreover, decreased BMD, trabecular number and thickness were observed in keel bone of laying hens receiving supplementation at 29 and 37 WOA (P < 0.05); decreased levels of Li, Ca, Hg, and TI at 33 WOA and trabecular thickness at 37 WOA (P < 0.05) were also identified. mRNA levels of SOST and RANKL and the ratio of RANKL/OPG mRNA levels were increased in birds fed a SO-supplemented diet (P < 0.05); COL2α1, OPG, and POSTN were downregulated at all sampling points (P < 0.05). Taken together, results indicate that feeding laying hens a diet supplemented with soybean oil can decrease daily feed intake and impair keel bone health but not influence production performance and egg quality.

Effects of replacement genetically modified soybean meal by a mixture of: Linseed cake, sunflower cake, guar meal and linseed oil in laying hens diet. Production results and eggs quality

The Kulmilk® (KulM®) preparation containing linseed cake (300 g/kg), sunflower cake (350 g/kg), guar meal (300 g/kg) and linseed oil (50 g/kg) was studied as alternative to genetically modified soybean meal (GM SBM) in the diet of laying hens. Two hundred forty hens maintained in cages were divided into 5 groups (8 hens per cage × 6 replications). From 18 wk of life, the hens were fed five diets for 33 wks: Control without KulM®, and A, B, C, D with respective KulM® content: 109, 170, 222 and 292 g/kg replacing GM SBM. Laying performance, egg weight, conversion ratio and hen mortality was continuously controlled throughout the experiment. Hen body weight was determined on 0 and 32 wk of production. On 7, 15 and 23 wk of laying, analysis of fresh eggs and eggs were stored for 21 d was performed (20 eggs per group). On 7 and 23 wk of hen laying, cholesterol level and fatty acid profile was determined on fresh eggs and eggs stored for 21 d (6 eggs per group). Sensory assessment of eggs was performed on eggs 15 wks laying. Introduction of KulM® to the diet replacing GM SBM contributed to increas laying performance, reduced mean egg weight and the final hen body weight but it did not influence the weight of eggs per hen, conversion ratio and mortality. The best production results were obtained in group A. Positive impact of KulM® was observed on the albumen quality and the yolk index of fresh and stored eggs, as well as reduction of yolk adhesiveness after 21 d. Cholesterol level in yolks depended on the laying performance, thus KulM® had indirect influenced on its reduction, especially in group A. Linear relationship was demonstrated between KulM® level and reduction of SFA acids, particularly of C16:0 acid. KulM® contributed to increas share of C18:1, C18:3 and C22:6 acids and reduction of C20:1 and C18:2 acids in the yolk. The influence of KulM® on the content of individual mono- and polyunsaturated fatty acids was observed primarily in group D. No impact of KulM® on the sensory quality of eggs could be demonstrated. In summary, KulM® can be recommended as a safe and efficient substitute of GM SBM in laying hens diet, particularly at a concentration of the diet at 109 g/kg.

Variation and Association of Hen Performance and Egg Quality Traits in Individual Early-Laying ISA Brown Hens.

Simple SummaryThe feed consumption and feed efficiency, body weight, egg weight, and rate of lay of the hen, as well as the albumen, yolk, and shell characteristics of the egg, are important measures of productivity in the layer industry. While these data are easily collected on a flock basis, there is little information on the extent of variation among individual hens in the literature and much nutrition and management is based on accepting the expected average performance of a cohort of animals. Moreover, body weight or feed consumption may have implications for other traits such as egg or egg component variables. We have attempted to control environmental variables such as feed in order to investigate the inherent variation for these traits present in a flock of 450 individually caged ISA Brown hens in early lay, and their associations with egg measurements. The results from the study revealed important variation in daily feed intake, body weight, and albumen height. Feed intake and hen body weights were weakly associated with egg weight, while feed intake and body weights were not associated with albumen height. Body weight and feed consumption had only a weak linkage with egg weight and did not influence albumen quality.Uniformity in hen and egg traits is an important consideration in commercial layer flocks. There is little information on how individual hen feed consumption and body weight affect egg quality measurements. This study investigated the variation in performance traits of individual hens and associations with egg quality characteristics. Four hundred and fifty-five ISA Brown caged hens in early lay were monitored for 42 days (25 to 30 weeks of age) to collect hen feed consumption and egg production measurements. Forty-four hens from the flock were randomly selected and eggs were collected from the same hen once weekly for albumen, yolk, and shell assessment. The means ± standard deviation of average daily feed intake (ADFI), albumen height, initial body weight (IBW), and final body weight (FBW) were 124 g ± 15, 10.3 mm ± 1.5, 1802 g ± 129, and 2000 g ± 175, respectively. Albumen height was not associated with ADFI (r = 0.18, p = 0.21), IBW (r = −0.04, p = 0.79), or FBW (r = −0.06, p = 0.69). This study showed variation in feed intake, body weight, and albumen quality of individual early-lay hens. Feed intake and body weight did not influence albumen quality.

Various bone parameters are positively correlated with hen body weight while range access has no beneficial effect on tibia health of free-range layers

The aim of this study was to determine if body weight or range use has a significant impact on bone health in commercial free-range laying hens, and to correlate tibia bone quality parameters with individual range usage and body weight. A total of 30 Lohmann Brown hens at 74 wk of age were selected from a commercial free-range farm and were either classified as heavy (mean ± SEM body weight 2.11 ± 0.034 kg, n = 14) or light (1.68 ± 0.022 kg, n = 16) body weight, and also classified as rangers (accessed the range for 86.7% of available days, n = 16) or stayers (accessed the range for 5.00% of available days, n = 14). The left tibiae of all individuals were analyzed for morphological parameters using computed tomography, evaluated for bone breaking strength, and ashed to determine mineral composition. Keel bone scoring was performed based on observation. Data were analyzed using a 2 × 2 factorial ANOVA, and regression analysis was performed. There was no measurable effect of range usage on any of the tibia parameters investigated. The body weight was significantly correlated with tibia breaking strength (r = 0.59), tibia weight (r = 0.56), tibia length (r = 0.64), diaphyseal diameter (r = 0.61), and total tibia volume (r = 0.67). In conclusion, range access had no beneficial effect on bone health. The impact of internal hen house furnishing and movement on bone health needs further investigation.

INFLUENCE OF NATURAL CAROTENOIDS SUPPLEMENTATION IN DIET ON EGG YOLK COLOR AND SOME PRODUCTIVE PARAMETERS OF LOCAL HEN LAYERS

The present study was conducted to study the effect of adding different levels of lutein powder pure (LP),dried tomato pulp (DTP) and dried sweet red pepper powder (DSRP) (as natural colour additives) on some productive, egg quality parameters and economical efficiency of Silver Montazah (SM) local hen layers from the beginning of 40 to 48 weeks of birds age. A 2x3x3 factorial arrangement design was used in this experiment including two levels supplementation of LP (0 and 30 mg/kg diet), three levels of DTP (0, 15 and 30 g/kg diet), and three levels of DSRP (0, 2 and 4 g/kg diet) .A total number of 162 laying hens of Silver Montazah (SM) local strain were used in this experiment. All selected birds were randomly distributed into 18 treatments equal in number (9hens / each treatment). Laying hens of each treatment were nearly of an equal average body weight and similar average daily egg production .All birds of the experimental treatments were individually housed in wire-caged batteries and kept under the same managerial, hygienic and environmental conditions. Results obtained at the end of the experiment showed that the average live body weight of layers at the end of the experimental period was significantly (P≤0.05) affected by dietary LP levels, whereas, dietary DTP, DSRP levels had no significant effect on average live body weight of hens. The heavier live body weight was attained by layers fed 0 mg / kg diet LP and layers fed 30 g / kg diet DTP recorded the average higher LBW. While, layers fed the 0 g / kg diet DSRP showed the higher average LBW. Dietary LP and DTP levels had significant (P≤0.01) effect on average daily feed intake of layers. However, the higher average of daily feed intake was recorded by hens fed dietary 0 mg/ kg diet LP, 0 g/ kg diet DTP level and 2 g / kg diet DSRP levels. Dried sweet red pepper levels had no significant effect on average daily FI of layers during most of experimental periods. The higher average daily FI was shown by layers fed 2 g / kg diet DSRP level. No significant differences were found in average feed conversion of layers attributed to the dietary DTP and DSRP levels. However, the best average FCR values (3.37g feed/g egg mass) was recorded by layers fed the diet contained 0 mg/kg diet lutein powder level. Dietary LP and DTP levels had significant (P≤0.01) effects on average egg production (EP) rate, egg weight and egg mass of layers at the end of the experimental period. While, dietary DSRP levels had no significant effect on averages of egg production rate and egg mass of layers at the end of the experimental period (40-48 weeks of age). The higher averages of egg production rate and egg mass were recorded by layers fed the diet of 0 mg/kg diet LP, 30 g/kg diet DTP and 2 g/kg diet DSRP levels, while, the higher average of egg weight was recorded by hens fed the dietary 0 mg/kg diet LP, 30 g/kg diet DTP and 0 g/kg diet DSRP levels . Dietary supplementation of LP, DTP and DSRP showed significant (P≤0.01) effect on Roche yolk color fan score at all the different experimental periods. Roche yolk color fan score increased with increasing the rate of LP, DTP and DSRP levels in the diet of laying hens. Diets contained 0 mg LP /kg diet, 0 g DTP /kg diet and 4 g DSRP /kg diet levels recorded the higher (best) relative economical efficiency percentage for egg production.