Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 3 )

2018 ( 7 )

2017 ( 4 )

2016 ( 11 )

Custom range...

Search Results: 1 - 10 of 478 matches for " laying hens "
All listed articles are free for downloading (OA Articles)
Page 1 /478
Display every page Item
Effect of Citric Acid, Phytase and Calcium Levels on the Calcium and Phosphorus Content in Egg: Yolk-Albumen and Shell, Yolk Color and Egg Quality in Diets of Laying Hens  [PDF]
Lily M. Vargas-Rodríguez, Jesús E. Morales-Barrera, José G. Herrera-Haro, Juan Antonio-Bautista, Roberto López-Pozos, David Hernández-Sánchez
Food and Nutrition Sciences (FNS) , 2016, DOI: 10.4236/fns.2016.714124
Abstract: To evaluate the effect of different levels of citric acid (CA) combined with phytase and calcium levels in the diets of laying hens on the calcium and phosphorus (P) contents of eggs: yolk-albumen and shell, yolk color and egg quality. A study was conducted with 24-week-old laying hens fed with a diet based on sorghum and soybean meal with 2.7 Mcal of EM/kg, 15% crude protein, 3.25% calcium and 0.25% available P. The levels of CA, phytase and calcium were 0%, 0.6% and 1.2%; 0 and 300 units of phytase (PHYU)/kg; and 3.0% and 3.25%, respectively. Phytase was added as an ingredient into to the diets, contributing 0.1% P and 0.3% calcium. A completely randomized factorial experiment was performed with a 3 × 2 × 2 design and 4 replications. The CA increased (P < 0.05) the P in the shell, and the combination of 1.2% CA, 300 PHYU phytase and 3.25% calcium increased (P < 0.05) the calcium in the eggshell. There was a CA × phytase × calcium interaction (P < 0.05) affecting egg yolk pigmentation; there were no differences in egg quality. It was concluded that adding CA to the diets of laying hens increases eggshell calcium content, and improves the phytase response. 1.2% CA × Phytase × 3.25% calcium significantly increases shell calcium by 0.56 g. Under the conditions of the present investigation, it would imply greater resistance of the eggs to be broken in the handling from the farm to the sales centers and consumer. Phytase interacts negatively with 0.6% CA at low calcium levels to degrade the yellow pigmentation of the yolk.
Feather loss in laying hens
Hristov Slav?a,Mitrovi? Sreten,Todorovi? Mirjana,?ermanovi? Vladan
Veterinarski Glasnik , 2006, DOI: 10.2298/vetgl0602107h
Abstract: The paper examined the incidence of different forms of feather loss and cannibalism in laying hens aged 74 weeks following moulting and in laying hens following exploitation for a period of one year. The forms of feather loss were considered in detail through a repeated examination of video recordings and they were sorted according to localization - to feather loss on the ventral part of the neck, on the dorsal part of the neck, and on the back between the wings. Feather loss on the ventral part of the neck was established in 47.9% hens, and in the dorsal part in 16.77% hens of the 167 laying hens aged 74 weeks following moulting. The group of 129 laying hens that were observed following one-year exploitation exhibited considerably more frequent feather loss, in 96.90% hens it was localized on the ventral part of the neck, in 60.47% hens on the dorsal part of the neck, and in 20.16% hens it was localized on the back between the wings. A comparison of the results of the incidence of co localized forms of feather loss in the one and the other group of laying hens using the t-test showed statistically very significant differences. A detailed consideration of the video recordings using the method of sequence analysis did not reveal any cannibalism in either group of laying hens.
Effects of Different Levels of Lysine and Protein on the Performance of Hy-Line Layers
M. Bouyeh,J. Pourreza,A. H. Samie
Journal of Science and Technology of Agriculture and Natural Resources , 2002,
Abstract: An experiment was carried out to determine the effects of different levels of lysine and protein on the performance of 240 Hy-Line W36 layers. Ten experimental diets were tested in a 2×5 factorial arrangement with a completely randomized design. Two basal diets (13 and 14% protein) were tested at different levels (10 and 20% lower than NRC, NRC and 10 and 20% above NRC recommendations). Dietary lysine levels were 0.56, 0.62, 0.69, 0.76 and 0.83%. During the three months of experimental period, egg production, egg weight, egg output, feed intake and conversion and lysine and protein intake were determined. The results indicated that 0.76% lysine and more (10 and 20% above NRC recommendation) with 13% dietary protein led to significantly (P
The Effect of Different Levels of Sesame Oil on Productive Performance, Egg Yolk and Blood Serum Lipid Profile in Laying Hens  [PDF]
Nguyen Duy Hoan, Mai Anh Khoa
Open Journal of Animal Sciences (OJAS) , 2016, DOI: 10.4236/ojas.2016.61011
Abstract: Addition of sesame oil into layer diets has been proved to enrich the proportion of polyunsatu-rated fatty acids in animal’s products. In this study, the effects of different levels of sesame oil in the diets on the performance, egg yolk and blood serum lipid profile of Isa Brown laying hens were investigated. A total of 96 layers were assigned into 4 groups to receive either 1 of 4 different diets contained 0.0%, 1.5%, 3.0% and 4.5% sesame oil, respectively. Sample of 12 eggs obtained from each groups were assessed for egg quality. The egg yolk fatty acid profile was determined with gas chromatography. Results revealed that the higher levels of sesame oil in the diet decreased egg production, egg weight, and egg yolk color except feed conversion ratio. In addition, supplementation of sesame oil increased the flow index of the eggs and the Haugh unite. The egg yolk lipid profile was not significantly different in the sesame oil fed groups, whereas, compare to control, it decreased the level of cholesterol. The blood serum lipid profile decreased in the sesame oil groups compare to control group. Meanwhile, monoacildigliserol also decreased in the sesame addition groups. In parallel with increasing levels of sesame oil, monounsaturated fatty acid (oleic acid) in the egg yolks significantly increased compared to the control (37.00%, 42.89%, 42.20% and 43.48%, respectively). It can be implied that sesame oil supplementation into the laying hens diet is necessary to produce monounsaturated fatty acid (MUFA) enriched eggs.
Effect of Supplemental Oregano Essential Oils in Diets on Production Performance and Relatively Intestinal Parameters of Laying Hens  [PDF]
Xianjing He, Dandan Hao, Chunhai Liu, Xu Zhang, Dandan Xu, Xiaonan Xu, Jianfa Wang, Rui Wu
American Journal of Molecular Biology (AJMB) , 2017, DOI: 10.4236/ajmb.2017.71006
Abstract: This study was designed to investigate the effects of dietary oregano essential oils on 150 30-week-old Hy-Line Layers’ productive performance, egg quality characteristics, cecal microbiota, digestive enzyme activities, mucosa structure of the duodenum and jejunum and glucose and small peptides transporters expression in the duodenum and jejunum. All hens were allocated into one of five different groups: negative control (NC; basal diet only), antibiotics control (CS; basal diet plus 100 mg/kg of 10% colistin sulfate) and treatments I, II, and III (basal diet supplemented with 50, 100 and 150 mg/kg oregano essential oils, respectively). The results showed that the laying rate, average egg weight, feed conversion ratio and the activities of amylase and trypsin were significantly improved by a diet supplemented with 100 mg/kg oregano essential oils (P < 0.01). The addition of oregano essential oils increased the number of intestinal Bifidobacterium and Lactobacillus significantly (P < 0.01), whereas the number of intestinal Escherichia coli and Salmonella was significantly (P < 0.01) decreased. The addition of 100 mg/kg oregano essential oils increased duodenum villus height (P > 0.05), significantly increased duodenum villus-height-to-crypt-depth ratios (P < 0.01) and decreased crypt depth in the duodenum (P < 0.05). Furthermore, the glucose transporter 2 (GLUT2), peptide transporter 1 (PepT1) and sodium-glucose cotransporter 1 (SGLT1) gene expression levels in the duodenum and jejunum were significantly increased in laying hens on a diet supplemented with 100 mg/kg oregano essential oils (P < 0.01). However, egg weight, relative eggshell weight, yolk index and Haugh unit value were not significantly affected by the addition of oregano essential oils (P > 0.05).
Efeito de Bixa orellana na altera??o de características de ovos de galinhas
Harder, Marcia Nalesso Costa;Brazaca, Solange Guidolin Canniatti;Savino, Vicente José Maria;Coelho, Antonio Augusto Domingos;
Ciência e Agrotecnologia , 2008, DOI: 10.1590/S1413-70542008000400030
Abstract: this research evaluated the effects of addition of anatto (bixa orellana l.) to feed laying hens to verify the possible interference of the anatto on egg quality. the eggs were obtained from 125 animal divided in 5 treatments: control (0% - t1) and four treatments with addition of anatto (0.5% - t2; 1.0% - t3; 1.5% - t4 and 2.0% - t5). the laying hens were separated in five blocks, each block with 5 animals, with total 25 animals by parcel. the eggs picked were classified using eggscopic, weighed, specific gravity, haugh unit, albumen and yolk height, thickness of the shell, diameter and index yolk. different feeds did not modify: weight; specific gravity; albumen height, thickness of the shell; yolk height and diameter of yolk. about the eggs quality analysis, addition of anatto did not show significance (p>0.05) among the treatments to most of the parameters of physical quality of eggs, only haugh unit and yolk index showed differences (p<0.05).
Occurrence of Salmonella sp in laying hens
Gama, NMSQ;Berchieri Jr, A;Fernandes, SA;
Revista Brasileira de Ciência Avícola , 2003, DOI: 10.1590/S1516-635X2003000100002
Abstract: this study was carried out to investigate the presence of salmonella sp in flocks of white laying hens. in different farms, the transport boxes of twelve flocks were inspected at arrival for the presence of salmonella. four positive (a, b, l and m) and one negative (i) flocks were monitored at each four weeks using bacteriological examination of cecal fresh feces up to 52 weeks. birds were also evaluated at 52 weeks, when 500 eggs were taken randomly, and at 76 weeks, after forced molt. salmonella enterica serovar enteritidis and s. enterica rough strain were isolated from the transport boxes of the four positive flocks (flocks a, b, l and m). salmonella sp was not isolated from the transport boxes or from the feces after 76 weeks-old in flock i. salmonella sp was isolated in the 1st, 11th, 34th, 42nd and 76th weeks from flock a; in the 1st, 4th, 11th and 76th weeks from flock b; in the first week and in the 17th to 52nd weeks from flock l; and in the 1st and 76th weeks from flock m. s. enteritidis, s. enterica rough strain and salmonella enterica serovar infantis were isolated from the four positive flocks. besides, salmonella enterica serovar javiana was isolated from flocks b and l, and salmonella enterica serovar mbandaka was isolated from flock l. eggs produced by flock a and by flock l were contaminated with s. enteritidis and s. enterica rough strain. according to these results, salmonella-infected flocks may produce contaminated eggs.
Suplementa??o de Ferro para Poedeiras Comerciais de Segundo Ciclo de Produ??o
Bertechini, AG;Fassani, éJ;Fialho, ET;Spadoni, JA;
Revista Brasileira de Ciência Avícola , 2000, DOI: 10.1590/S1516-635X2000000300009
Abstract: the objective of this work was to evaluate the effects of the supplementation of iron in ration based on corn and soybean meal, on the productive performance, egg quality , egg yolk iron deposition and blood parameters of commercial laying hens in second production cycle. 240 commercial lohmann-lsl laying hens with 72 weeks of age were submitted to the forced molt. the hens were raised in the conventional cage by using three hens by cage (25 x 45 x 40cm). a completely randomized design was utilized, with treatments based on five iron supplementation levels (0, 20, 40 60 and 80ppm) in the ration, with four replications and three evaluations periods of 28 days each. the corn/soybean meal based diet were used, containing 127 ppm of analysed iron. the iron supplementation did not affect the productive performance and internal and external eggs quality and analysed blood parameters . the content of iron egg yolk (mg/100g) increased linearly when iron supplementation increased in the diet at the level of 80 ppm, used in this research.
Efeito da densidade na gaiola sobre o desempenho de poedeiras comerciais nas fases de cria, recria e produ??o
Pavan, Ana Cláudia;Garcia, Edivaldo Ant?nio;Móri, Cleusa;Pizzolante, Carla Cachoni;Piccinin, Adriana;
Revista Brasileira de Zootecnia , 2005, DOI: 10.1590/S1516-35982005000400029
Abstract: this trial was conducted to evaluate the effect of different stocking densities on performance of caged layers during the growing and laying periods and to verify the effects in the next phase. in the growing period (0-6 weeks), eight hundred and four chicks (isa brown ) were assigned to 100 x 80 x 35 cm cages, according to a completely randomized design, with four treatments (275.86, 250.00, 228.57, and 210.52 cm2 per bird) and four replicates. no significant effects of treatments on weight gain, feed intake, feed conversion and uniformity were observed during the growing period. in the 6-16 w period, 720 pullets were randomly assigned to 100 x 50 x 50 cm cages, according to a completely randomized design of 4 x 3 factorial arrangement (four densities from 0-6 weeks and three densities from 6-16 weeks), with different treatments (500.00, 416.67, and 357.14 cm2 per bird) and four replicates. no significant differences among treatments in the 6-16 w period on weight gain, feed intake, feed conversion and uniformity were observed. in the laying phase, 540 laying hens were randomly assigned to 100 x 45 x 45 cm cages, according to a completely randomized design of 3 x 3 factorial arrangement (three stocking densities in the 6-16 w periodand three caging densities in the laying phase), with different treatments (562.15, 450.00, and 375.00 cm2 per hen) and five replicates. significant effects of cage density on egg weight and feed intake were detected. no significant effects of cage density on bird performance in the growing and laying periods were observed.
Effect of methionine levels on production performance, triglyceride and non-esterified fatty acid in laying hens
Poosuwan, P.,Bunchasak, C.,Markvichitr, K.,Nukraew, R.
Songklanakarin Journal of Science and Technology , 2006,
Abstract: This study was conducted to evaluate the effect of methionine (Met) on egg production, liver triglyceride and blood free fatty acid (non-esterified fatty acid; NEFA) in laying hens aged 21 to 32 weeks old by using completely randomized design. Low-protein diet (14% CP) containing Met at 0.28 (unsupplemented group), 0.30, 0.38 or 0.44% of diet were used. The results showed that egg production and egg mass tended to increase, while feed and energy efficiency were significantly improved when Met levels increased (p<0.05).Liver weight and liver triglyceride were significantly increased by the Met supplementation, but there was no evidence of fatty liver syndrome. In addition, NEFA was slightly decreased but body weight tended to increase due to adding Met, although statistical differences were not seen. In conclusion, the improvement of egg production caused by an increase of Met levels may be closely related with the changing proportion of lipogenesis and lipolysis due to an improving amino acid balance.
Page 1 /478
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.