scholarly journals The Effect of Tranquilizers on Egg Production and Egg Shell Quality in Caged Layers

1961 ◽  
Vol 40 (5) ◽  
pp. 1315-1321 ◽  
Author(s):  
H.J. Eoff ◽  
R.E. Davies ◽  
T.M. Ferguson ◽  
J.R. Couch
Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 897
Author(s):  
Marianne Hammershøj ◽  
Gitte Hald Kristiansen ◽  
Sanna Steenfeldt

Egg laying genotypes have been selected for generations due to their high yield and egg quality, resulting in efficient feed utilization and low body weight; hence, they are not suitable for meat production. This imposes an issue for the male layer chicks, which are killed at one day old. Because of ethical and food waste concerns, the search for suitable dual-purpose genotypes in order to avoid euthanasia of male day-old chicks has intensified. The aim of the present study is to evaluate potential dual-purpose genotypes for their egg quality compared to a representative egg laying genotype. Three dual-purpose genotypes with divergent characteristics were evaluated: genotype A represented an experimental crossbreed based on a broiler type male and an egg layer female, genotype B was a pure breed, and genotype C was a crossbreed of a layer type. These were compared to a control genotype D, which was an egg layer. Eggs were collected six times during the period of 21–54 weeks of hen age, i.e., a total of 1080 shell eggs were analyzed. Examined parameters were weights of egg, shell, yolk, and albumen, by calculating their relative proportions. Shell quality was assessed by shell strength, shell stiffness, and shell thickness. Yolk quality was determined as yolk color and inclusions of blood and meat spots, and albumen quality was evaluated in terms of pH and dry matter (DM) content. The egg layer genotype produced the smallest eggs with least blood and meat spot inclusions compared to that produced by the three dual-purpose genotypes. Shell quality was superior for the layer genotype. However, the experimental genotype A laid eggs of comparable shell quality, albumen DM, and yolk weight, but also with the darkest and most red-yellow colored yolk. The two other dual-purpose genotypes produced eggs of low-medium quality. In conclusion, the genotype A could serve as dual-purpose genotype from an egg quality perspective.


2018 ◽  
Vol 98 (4) ◽  
pp. 619-630 ◽  
Author(s):  
D. Kumar ◽  
C. Raginski ◽  
K. Schwean-Lardner ◽  
H.L. Classen

Ideally balanced dietary protein is critical for laying hen egg production and feed efficiency, but also affects other important characteristics. This research was designed to study the nonegg production and feed intake response of Lohmann-LSL Lite hens to 550, 625, 700, 775, and 850 mg d−1 of amino acid balanced digestible lysine (Dlys) from 27 to 66 wk of age. Data collection included hen weight (HW), feather scoring, tissue weights, egg specific gravity, egg component weights, and excreta nitrogen (N) content. The experiment was a completely randomized design and level of significance was fixed at P ≤ 0.05. Hen weight (quadratic, Q), pectoralis muscle (absolute, % – Q), and abdominal fat (absolute – linear, L; % – Q) increased with increasing Dlys intake. Although gastrointestinal segment weights and lengths were affected by Dlys intake, interpretation of results was confounded by other aspects of diet composition. Hen feather score (L) and excreta N content (Q) increased, and egg shell quality (L) decreased with increasing Dlys intake. Absolute egg component weights increased with Dlys intake, but effects on proportional weights were Q and relatively minor. In conclusion, balanced Dlys intake affected a variety of practical nonproduction characteristics in laying hens.


1998 ◽  
Vol 49 (2) ◽  
pp. 279 ◽  
Author(s):  
D. Balnave ◽  
S. K. Muheereza

Point-of-lay pullets were housed in 2 temperature-controlled rooms maintained at a constant 32°C with either a conventional 16 h light : 8 h dark (16L : 8D) or an intermittent 3L : 1D lighting regimen. They were fed either a conventional layer diet (12·0 MJ of ME and 199 g crude protein/kg) or this diet supplemented with 1% sodium bicarbonate (NaHCO3). Production and egg shell quality measurements were made at 8-week intervals from 22 to 62 weeks of age. All measures were influenced by age. The 3L : 1D regimen significantly increased feed intake (P < 0·001), weight gain (P < 0·01), egg weight (P < 0·001), egg shell breaking strength (P < 0·001), and shell thickness (P < 0·01). Significant age×light interactions were observed for feed intake, egg production, and egg mass. Hens in the 3L : 1D regimen ate significantly (P < 0·001) more food and produced significantly (P < 0·01) greater egg mass to 46 weeks of age. No significant differences were observed after 46 weeks. Although not significant, NaHCO3 consistently improved shell breaking strength. The response was small in the 16L : 8D regimen (3%) compared with the 3L : 1D environment (7%), the latter being additional to the 14% improvement resulting from the use of the 3L : 1D regimen. The results indicate advantages from the use of intermittent lighting and dietary NaHCO3 supplementation at high temperatures.


1981 ◽  
Vol 21 (110) ◽  
pp. 287
Author(s):  
H Karunajeewa ◽  
M Fox

In a 43x2 factorial experiment, 576 White Leghorn x Australorp pullets attaining 50% egg production at about 180 days of age were given from 22 to 26 weeks of age pre-layer diets with 10.4 or 25.8 g kg-1 calcium and 6.2 or 10.9 g kg-1 phosphorus. From 26 to 74 weeks of age these pullets were given layer diets with three levels (0, 1.5 and 7.0 g kg-1) of added sodium chloride and two levels (0 and 6.0 g kg-1) of added potassium sulfate. The calcium content of the pre-layer diet had no significant effect on feed intake, bodyweight gain or tibia-ash content between 22 and 26 weeks of age, or on egg production, egg weight, feed conversion efficiency and mortality in the subsequent laying phase. The higher level (25.8 g kg-1) of calcium improved (P<0.05) the shell quality of the first eggs laid and prevented a decline in shell quality due to excess sodium chloride (7.0 g kg-1) in the layer diet. A phosphorus level of 10.9 g kg-1 of the pre-layer diet reduced (P<0.05) feed intake, and in the subsequent laying phase both hen-housed egg production and efficiency of feed conversion were reduced (P<0.05). The adverse effect on feed conversion efficiency was alleviated by adding potassium sulfate to the diet. The level of phosphorus in the pre-layer diet had no significant effect on tibia-ash content or egg shell quality. The dietary level of sodium chloride had no significant effect on egg weight, feed intake and bodyweight gain. The inclusion of sodium chloride at a level of 7.0 g kg-1 diet tended to depress rate of lay by 2.0% and during the first half of the laying cycle, increased mortality by 12.5% (P<0.05) and reduced egg shell weight and thickness (P<0.05) in birds given pre-layer diets with a low calcium content. A daily intake of 137 to 139 mg of sodium per bird was not adequate for maintenance of egg production and efficiency of feed conversion in crossbred layers. The sodium requirement of a crossbred layer given a diet containing meat and bone meal is about 160 mg/day. The adverse effects due to either a low intake of sodium or a high level of sodium chloride in the diet were alleviated by the inclusion of 6.0 g kg-1 potassium sulfate in the diet. The inclusion of potassium sulfate (6.0 g kg-1) in the layer diet increased rate of lay by 2.1% (P<0.05).


Animals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2991
Author(s):  
Isabelle Ruhnke ◽  
Yeasmin Akter ◽  
Terence Zimazile Sibanda ◽  
Aaron J. Cowieson ◽  
Stuart Wilkinson ◽  
...  

Laying hens require substantial quantities of calcium (Ca) to maintain egg production. However, maintaining recommended dietary Ca through inclusion of limestone may impede nutrient digestibility, including that of other minerals. It was hypothesized that providing a separate source of dietary Ca in the form of limestone grit would preserve Ca intake of hens offered diets containing suboptimal Ca concentrations. Furthermore, the impact of dietary phytase at a “superdosing” inclusion rate on the voluntary consumption of limestone grit was evaluated. One hundred and forty-four laying hens (19 weeks of age) were assigned to one of six dietary treatments in a 3 × 2 factorial arrangement comprising three dietary Ca concentrations (40, 30, and 20 g/kg) and ±dietary phytase (3500 FYT/kg diet) on an ad libitum basis for six weeks. Limestone grit (3.4 ± 1.0 mm) was provided to all hens ad libitum. Hens offered diets containing phytase consumed significantly less limestone grit p = 0.024). Egg weight, rate of lay, and egg mass were unaffected by dietary treatment (p > 0.05). Egg shell weight % (p < 0.001), shell thickness (p < 0.001), and shell breaking strength (p < 0.01) decreased in line with dietary Ca levels. In summary, dietary superdosing with phytase reduced the consumption of a separate limestone source in individually housed, early lay ISA Brown hens. Egg shell quality variables but not egg production worsened in line with lower dietary Ca levels.


1990 ◽  
Vol 41 (6) ◽  
pp. 1187 ◽  
Author(s):  
I Yoselewitz ◽  
D Zhang ◽  
D Balnave

Supplementing the town water supply of laying hens with 600 mg sodium chloride (NaCl)/L significantly decreased egg shell quality and significantly increased the incidence of egg shell defects without affecting egg production and egg weight or food and water intakes. A smaller, but still significant, increase in egg shell defects was also observed with sodium bicarbonate (NHCO3) supplementation of town water. Ammonium bicarbonate (NH4HCO3) supplementation of town water had no significant effect on egg shell defects and, when added to drinking water containing NaCl, significantly reduced the incidence of shell defects. A smaller beneficial effect was observed when NHCO3was added to saline water. Ammonium bicarbonate, when added to saline drinking water at concentrations of 250 and 450 mg/L, reduced water intake, an effect not observed when these same supplements were added to town water. This suggests that the presence of NaCl in the water may affect kidney function so that the use of NH4HCO3may have limited value, especially at higher water salinities. Shell gland fluid composition was influenced less by treatment than by whether or not hens were laying eggs with defective shells.


1959 ◽  
Vol 39 (2) ◽  
pp. 176-181 ◽  
Author(s):  
T. M. MacIntyre ◽  
J. R. Aitken

Diets varying in protein content from 10.9 to 16.7 per cent were fed over a 336-day laying period to hens in both floor pens and individual laying cages. All rations were approximately iso-caloric, the mean productive energy value being 825 Calories per pound. Each ration was fed to 200–240 hens in four floor pens and to 90–96 hens in individual cages.A crude protein level of 13 per cent of the diet proved adequate for egg production, but egg weights and body weights were improved when the dietary protein was increased. Egg shell quality was highest on low protein diets. Interior egg quality was not affected by the protein level in the diet.On comparable diets, birds in individual laying cages laid fewer eggs and consumed less feed than birds in floor pens. Caged birds were heavier in body weight and laid heavier eggs with thicker shells than their counterparts in floor pens. The criteria employed in the measurement of interior egg quality showed no differences between the cage and pen environments, nor did there appear to be any differences in protein requirements between the two environments.


2015 ◽  
Vol 55 (8) ◽  
pp. 1056 ◽  
Author(s):  
W. Chen ◽  
H. X. Zhang ◽  
S. Wang ◽  
D. Ruan ◽  
X. Z. Xie ◽  
...  

The purpose of this study was to estimate the selenium (Se) requirement of egg-laying ducks based on daily egg production and the selenoprotein glutathione peroxidase (Gpx). Five-hundred and forty laying ducks were divided into six treatments, each containing six replicates of 15 ducks. The birds were caged individually and received a Se-deficient basal diet (0.04 mg/kg) or diets supplemented with 0.08, 0.16, 0.24, 0.32, 0.40 mg/kg Se (as sodium selenite) for 6 months. The experiment consisted of two periods: an early-laying period of 2 months and the peak-laying period of 4 months. Egg production and feed intake were recorded daily. At the end of the experiment, blood samples were drawn for determination of Gpx activity in plasma (Gpx3) and in erythrocytes (Gpx1). Hepatic Gpx1 activity and relative expression of Gpx1 mRNA were also determined. Eggs (n = 6) were sampled for quality determination and Se content at the end of the experiment. The activities of plasma Gpx3, erythrocyte Gpx1 and liver Gpx1 increased in a quadratic manner (P < 0.001) with increasing supplemental Se. The mRNA abundance of hepatic Gpx1 increased linearly (P < 0.001) with dietary Se supplementation. Egg shell thickness was significantly reduced in the ducks fed 0.44 mg Se/kg (P < 0.05), indicating that higher dietary Se tends to compromise egg shell quality. Yolk and albumen contents of Se increased linearly (P < 0.0001) with dietary Se supplementation. Using quadratic broken line models, the Se requirement for daily egg production was 0.18 mg/kg for early-laying ducks and 0.24 mg/kg for peak-laying ducks; for optimal function of Gpx (peak-laying ducks), it was 0.37 mg Se/kg.


2009 ◽  
Vol 49 (2) ◽  
pp. 162 ◽  
Author(s):  
K. K. Chousalkar ◽  
J. R. Roberts

The effects of two Australian strains of infectious bronchitis virus (IBV-T and N1/88) on the internal and external quality of eggs were studied in unvaccinated Isa Brown hens in full lay. Overall, there was no decline in egg production in either of the infected groups. However, there were some long-lasting negative effects on the egg internal quality of T-infected hens. Negative effects on internal quality in the N1/88-infected group were relatively short term. Yolk colour score was lower only in T-infected hens. Egg shell quality was affected only in terms of loss of egg shell colour. IBV infection resulted in paler egg shells in both the infected groups. Paler egg shells may not be regarded well by consumers. The egg shape index was lower in both infected groups.


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