Production Performance Of Layers Research Articles

Associations of the T329S Polymorphism in Flavin-Containing Monooxygenase 3 With Atherosclerosis and Fatty Liver Syndrome in 90-Week-Old Hens.

This study aimed to evaluate the effects of the spontaneous genetic mutation T329S in flavin-containing monooxygenase 3 (FMO3) on atherosclerosis (AS), fatty liver syndrome (FLS), and adiposity in 90-week-old layers. At 90 weeks of age, 27 FMO3 genotyped Rhode Island White chickens (consisting of nine AA hens, nine AT hens, and nine TT hens) with normal laying performance were selected. The AS lesions, incidence of FLS, fat deposition, metabolic characteristics, and production performance of these egg-layers with different FMO3 genotypes were assessed. The T329S mutation in TT hens reduced the AS lesions (P < 0.01) and altered the plasma metabolic indices more than it did in the AA and AT hens. Furthermore, it reduced the incidence of FLS, hepatic triglyceride deposition (P < 0.05), liver indices (P < 0.05), and fat deposition (P < 0.05) in the subcutis and abdomen of TT hens compared to those of AA and AT hens. Moreover, as an effect of T329S, TT hens laid a higher than average number of eggs and maintained a higher egg-laying rate from 68 to 90 weeks than AA and AT hens. Our study confirmed that the T329S mutation in FMO3 could reduce the development of AS lesions, the incidence of FLS, and fat deposition, which are associated with changes in plasma and hepatic metabolic indices and improvements in the laying performance of older layers. Our results may provide a new strategy for using the T329S mutation to improve the health status and production performance of layers during the late laying period.

The Effect of Supplementing Tea Polyphenols on Yolk Cholesterol and Production Performance of Laying Hens During the Egg-laying Period

This study aimed to investigate the effect of supplementing 300 mg/kg tea polyphenols (TP) on yolk cholesterol content and production performance of laying hens during the egg-laying period. A total of 600 Roman laying hens aged 24 weeks were randomly divided into two dietary treatment groups. The feeding experiment lasted for 48 weeks. Layers fed basal diet supplemented with 0 (control group) and 300mg/kg TP (TP group) diet, respectively. The yolk cholesterol content, laying performance, and egg quality were determined at 28, 38, 48, 58, and 68 weeks of age. The yolk cholesterol content in the TP group was significantly decreased at 28-68 weeks of age (p<0.01), compared to the control group. There was a significant increase in laying rate in the TP group at 38 weeks of age (p<0.05), compared to the control group, while no significant differences during the other laying periods were obtained (p>0.05). The FCR significantly decreased in the TP group at 38 weeks of age whereas AEW significantly increased in the TP group at 58 weeks of age (p<0.05). Similarly, the eggshell thickness and eggshell strength in the TP group significantly increased (p<0.05), compared with the control group at 38 weeks of age. The albumen height and Haugh unit significantly increased at 28 weeks of age (p<0.05). In conclusion, the results showed that the diet supplemented with 300 mg/kg TP had positive effects on production performance of layers during the egg-laying period, and could lessen yolk cholesterol content significantly at 28-68 weeks of age.

Effect of a targeted treatment strategy against Ascaridia galli on egg production, egg quality and bird health in a laying hen farm

Worm control is an important aspect of the successful management of the egg production industry. Of particular concern is Ascaridia galli, which at high parasite loads affect health and production in layers. Application of a targeted treatment strategy (TT) to control A. galli has shown promise. The purpose of this study was to explore the effect of such a strategy on welfare indicators and production performance of layers. Six flocks (F1–6) on a commercial farm were allocated to three treatment groups. Flocks F1 and F4 were treated (TT) with fenbendazole at 22, 27 and 36 weeks post-placement (WPP). Flocks F2 and F5 were treated at 27 WPP (conventional treatment, CT) and hens in flocks F3 and F6 served as untreated (UT) control groups. At 19, 35 and 45 WPP twenty-five hens plus thirty eggs per flock were randomly selected. Hens were weighed and their plumage conditions (PC) were assessed. The eggs were subjected to various external and interior quality analyses. Production data such as number of eggs/hen/week, egg mass and feed conversion ratio (FCR) were calculated from raw data obtained from all flocks on a weekly basis. The number of eggs/hen/week, egg mass and FCR were higher (P < 0.05) in the TT flocks and hens had better PC both at 35 and 45 WPP compared with other flocks. No differences in body weight and physical egg quality were observed between groups except for egg shell strength which was higher (P < 0.05) in the CT flocks. These data suggest that better production performance and plumage, which suggests improved health, can be achieved through the application of a TT strategy. The insights gained from this research should help to justify the extra cost and labor associated with the TT strategy.

Effect of Supplementation of Fermented Yeast Culture During Summer on Plasma Leptin and Ghrelin and Expression of their Receptors in Different Tissues and on Production Performance During-Post Summer Period in PD 3 Chicken Line

The present experiment was conducted to observe the effects of supplementation of fermented yeast (Saccharomyces cerevisiae) culture (FYC, a commercial product at 1.5×107 cfu/g) on physiological blood parameters, expression of genes for hormone receptors and on production performance of layers during summer season. The control group was devoid of supplementation of FYC. A total of 150 layers (PD 3 chicken line; 17 weeks age) were divided into three equal groups each comprising of 10 replicates of 5 birds. The dietary treatments included supplementation of FYC to the basal diet at 0 (C; control), 0.5 (T1) and 1.25 (T2) g/kg. The results indicated that the concentration of the hormones leptin and ghrelin was significantly (P<0.01) greater for the control group. Further, the plasma concentration of malondialdehyde (MDA) (P<0.01) and total cholesterol (P<0.05) were significantly greater at 49d of the experiment in the control group when compared with the respective parameters in the group of birds supplemented with the higher dose (1.25 g/kg) of yeast culture (T2). The expression of leptin-and ghrelin-receptors was downregulated in the treatment groups significantly (P<0.05) in brain, liver (T2) and magnum (portion of reproductive tract) tissues (T1). The histopathological evaluation of the intestinal tissues indicated that the severity of the necrosis of the villi of the jejunum was mild for the treatment groups when compared with that of the control (C) group. Hence, it can be concluded that supplementation of yeast culture @ 1.25 g/kg was beneficial in lowering stress markers like cholesterol, MDA and further reducing the severity of necrosis resulting in increased egg production, fertility and hatchability.

Study of Production Performance of Layers in Different Types of Cages with Different Stocking Densities

Study of Production Performance of Layers in Different Types of Cages with Different Stocking Densities

Effects of supplementing microalgae in laying hen diets on productive performance, fatty-acid profile, and oxidative stability of eggs

The purpose of this trial was to investigate the effects of adding graded levels of dehydrated, whole-cell microalgae (All-G-RichTM, Alltech Inc.) in layer diets on the performance, egg and shell quality, yolk color, oxidative stability, and fatty-acid concentration of eggs. Six replicate groups of 5 Hy-Line W-36 laying hens were assigned to each of 4 dietary treatments. Treatments consisted of feeding a corn-soybean meal control diet alone or supplemented with 1.0, 2.0, or 3.0% All-G-RichTM during a 32-wk production period. Fatty-acid content of egg yolk was analyzed after feeding the experimental diets for 4 wk. The docosahexaenoic acid (DHA) content in egg yolk was linearly increased (P < 0.01) with increasing levels of algae in the diet. There was no effect of dietary treatments on production performance of layers in the entire trial period. Egg weight and eggshell quality were not affected by dietary treatments. Supplements of 2 or 3% All-G-RichTM significantly increased redness (a*) and decreased lightness (L) of egg yolk. Yolk fatty-acid oxidation, as measured by thiobarbituric acid reactive substances (TBARS), was not affected by treatments in eggs stored up to 30 d at 4°C. Based on these data, adding All-G-RichTM in layer diets can produce DHA-enriched eggs with no negative impact on egg quality.

Effect of Low Nutrient Density Diets and Certain Feed Additives on Performance of Laying Hens

A trial was conducted to investigate the effect of feeding low nutrient density diets with certain dietary agents on the egg production and nutrient metabolizability of layers (n=144). A practical type layer diet (BIS, 1992) served as control and test diets were prepared by replacing 10, 20 and 30 per cent of the control diet by a diluent feed ingredient i.e., sun-dried sugarcane press residue. Further, each diet was fortified with either lipid utilizing agents (lipase 100 units + lecithin 20 g/kg diet) or NSP degrading enzymes (xylanase 1000, β-glucanase 400, cellulose 200, pectinase 100 units/kg feed) or together to result in another set of three diets. Each diet was offered to triplicate groups of three laying hens (35 wks old, BV-300 birds) each for 56d. The results revealed a significant (P 0.05) among different groups. Further, the egg production, feed consumption, feed efficiency and egg qualities were similar (P>0.05) among the groups fed diets supplemented without or with lipid utilizing agents or NSP degrading enzymes or together. It was concluded that the diet dilution decreases the production performance of layers without affecting egg qualities.

Effect of dietary lipid saturation on the production performance of layers

This study investigated the effects of dietary lipid saturation on production parameters of laying hens during the peak-of-lay period. Five isoenergetic (12.6 MJ AME/kg DM) and isonitrogenous (170 g CP/kg DM) diets were formulated, using a control diet (50 : 50 blend of fish- and linseed oil), fish oil (poly-unsaturated n-3), sunflower oil (poly-unsaturated n-6), high oleic acid sunflower oil (mono-unsaturated n-9 ) and tallow (saturated) at a 30 g/kg inclusion level. Two hundred individually caged HyLine Silver-Brown hens (20 weeks of age) were randomly allocated to the five dietary treatments (n = 40 replicates/treatment). Hens received their respective experimental diets until 40 weeks of age. During weeks 24, 28, 32, 36 and 40 all eggs produced, were recorded, individually weighed and the daily feed intake of birds determined. Data for the respective collection weeks were pooled for calculation of production parameters during peak-of-lay. Dietary lipid saturation level had no effect on daily feed intake of hens, hen-day egg production, egg output and live weight of hens during the peak-of-lay period. The mono-unsaturated n-9 diet (high oleic acid sunflower oil) had the lowest feed efficiency (0.47), while that of the control-, polyunsaturated n-6 (sunflower oil) and the saturated (tallow) treatments were the highest (0.49). Results of the current study suggest that although dietary lipid saturation level had no effect on most of the production performances, it might influence the efficiency of feed utilization.Keywords: Cracked eggs, egg output, feed efficiency, α-linolenic-, linoleic-, oleic-, docosahexanoic acid

Effect of Nest Design, Passages, and Hybrid on Use of Nest and Production Performance of Layers in Furnished Cages

Production performance, including egg quality, and proportion of eggs laid in nests were studied in furnished experimental cages incorporating nests, litter baths, and perches. The study comprised a total of 972 hens of two genotypes: Lohmann Selected Leghorn (LSL) and Hy-Line White. The birds were studied from 20 to 80 wk of age, and conventional four-hen cages were included as a reference. In furnished cages for six hens, the effects of 30 or 50% vs. 100% nest bottom lining (Astro turf®) were studied with LSL hens. Nest bottom lining had no significant effect on egg production or proportions of cracked or dirty eggs, but the use of nests was significantly higher in cages incorporating nests with 100% lining, compared with 50 or 30%. The two hybrids were compared when housed in large, group-furnished cages for 14 or 16 hens of two designs; with a rear partition with two pop holes or fully open, i.e., no rear partition. LSL birds produced significantly better and had a significantly lower proportion of cracked eggs. There was no difference between H- and O-cages, either in production or in egg quality. LSL birds laid a significantly lower proportion of eggs in the nests, especially in O-cages, implying a significant hybrid × cage interaction. When housed in conventional cages, the hybrids did not differ in proportion of cracked eggs but differed in production traits. It was concluded that with the present nest design, the proportion of nest bottom lining cannot be reduced without affecting birds' use of nests, but the proportion did not affect exterior egg quality. The effect of genotype should be considered in the further development of furnished cages.