Factors Affecting Feed Efficiency for Egg Production in Selected Strains of Caged Layers

Abstract Background: The absorption and transportation of calcium and phosphorus is mainly relied on their corresponding transporters. Eggshell is mainly formed during dark time in one egg cycle. The aim of this study was to determine the effect of different light regime on eggshell quality and the expression of the relevant calcium and phosphorus transporters in laying hens. Seventy two 56-week-old laying hens were randomly divided into two groups and subjected to the following treatments: 16 h light: 8 h dark (control) and 9 h light: 15 h dark (LDP). The expression of phosphorus transporters type IIb Na/Pi co-transporter NaPi-IIa (NPt2a) and NaPi-IIb (NPt2b), calcium transporter calbindin-D28k (CaBP-D28k), and plasma membrane Ca ATPase 1b (PMCA1b) were measured in small intestine, kidney, and eggshell gland. Results: The results showed that the feed intake (P < 0.001) and egg weight (P = 0.05) was decreased by LDP treatment, while laying rate, egg production, and feed efficiency were not significantly influenced (P > 0.05). Compared to control, eggshell hardness was increased (P < 0.05) by LDP treatment whereas eggshell thickness and eggshell percentage were not significant changed. Eggshell calcium (Ca) and phosphorus (P) contents were elevated in LDP-hens, compared to control birds. Compared to control birds, serum Ca (P < 0.01) and P levels (P = 0.079) at dark time were increased in LDP-hens while and alkaline phosphatase (ALP) activity was lowered (P < 0.05). The protein expression levels of CaBP-D28k and PMCA1b were not influenced in duodenum but were decreased at light time in jejunum of LDP hens. In kidney, the expression of CaBP-D28k, PMCA1b and NPt2a were not changed by LDP treatment. In eggshell gland, however, the expression of CaBP-D28k and osteopontin (OPN) were relative higher in LDP hens compared to control birds, whereas the PMCA1b expression was not altered. Conclusions: The result indicates that the increased circulating Ca and P concentrations in dark time are favorable for the deposition of calcium and phosphorus in eggshell. The result offers an alternative strategy for the laying hen with a worse eggshell problem.

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Effects of a short laying rest on postrest egg production and egg quality

Agricultural and Food Science ◽

10.23986/afsci.72660 ◽

1993 ◽

Vol 2 (5) ◽

pp. 437-445

Author(s):

Tuomo Kiiskinen ◽

Hilkka Hakatie

Keyword(s):

Mass Production ◽

Feed Efficiency ◽

Egg Production ◽

Egg Quality ◽

Live Weight ◽

Egg Mass ◽

Whole Grain ◽

Egg Weight ◽

Egg Shell ◽

Production Period

Two factorial trials, each including three commercial laying hybrids, were conducted to study the effects of a short laying rest on postrest performance of hens and on egg quality. A total of 1800 hens laying at 65% on an average (70 wks of age) were subjected to one of the following treatments: no rest (control, C) or feeding only whole-grain barley (WB) or fasting (F, Trial 1 only) until the rate oflay dropped to 0%, after which the birds were returned to the previous all-mash diet. The second laying period was six months. Egg production of the WB and F hens ceased within one week on an average and the birds were out of production for 10 days. Laying intensity during the second production period did not differ significantly between the treatments in each trial, but egg weight and daily egg mass production increased as a result of the rest treatments. The laying rest procedures reduced feed intake, improved feed efficiency and increased live weight significantly. Egg shell and albumen quality traits were significantly better in the laying rest groups than in the controls. Significant differences in performance and egg quality between the hybrids were mainly ascertained in Trial 2. The results suggest that a short laying rest is a feasible means of improving egg quality towards the end of the laying period. It can be accomplished successfully by feeding whole-grain barley.

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Factors affecting egg production in the selfing mangrove rivulus ( Kryptolebias marmoratus )

Zoology ◽

10.1016/j.zool.2017.02.004 ◽

2017 ◽

Vol 122 ◽

pp. 38-45 ◽

Cited By ~ 5

Author(s):

Justin L. Lomax ◽

Rachel E. Carlson ◽

Judson W. Wells ◽

Patrice M. Crawford ◽

Ryan L. Earley

Keyword(s):

Egg Production ◽

Factors Affecting ◽

Kryptolebias Marmoratus ◽

Mangrove Rivulus

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Genetic factors affecting feed efficiency, feeding behaviour and related traits in pigs

Achieving sustainable production of pig meat Volume 2 - Burleigh Dodds Series in Agricultural Science ◽

10.19103/as.2017.0013.06 ◽

2017 ◽

pp. 75-96

Author(s):

Duy Ngoc Do ◽

◽

Haja N. Kadarmideen ◽

Keyword(s):

Feed Efficiency ◽

Feeding Behaviour ◽

Genetic Factors ◽

Factors Affecting

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RESPONSE OF LAYING HENS TO GRADED LEVELS OF DIETARY NUTRAFOS 3 IN A HUMID TROPICAL ENVIRONMENT

Nigerian Journal of Animal Production ◽

10.51791/njap.v15i.1233 ◽

2021 ◽

Vol 15 ◽

pp. 185-196

Author(s):

M. MONSI ◽

A. O. AMAKIRI

Keyword(s):

Treatment Effect ◽

Feed Efficiency ◽

Egg Production ◽

Egg Size ◽

Laying Hens ◽

Gallus Domesticus ◽

Feed Consumption ◽

Tropical Conditions ◽

Overall Performance ◽

Haugh Unit

Four groups of 48 laying hens (Gallus domesticus), midway in their laying cycle were fed diets containing graded levels (0.00%, 1.5%, 2.5% and 3.5%) of dietary Nutrafos 3 for 56 days. The completely randomized experimental arrangement was designed to evaluate the responses of the caged layers to the inclusive levels of the additive under humid tropical conditions. The dietary additive produced statistically significant (P< 0.01) improvements in the rate of egg production of the hens. Significant increases (P< 0.01) in feed consumption and improvements in feed efficiency (P < 0.01) were also observed. Haugh unit was significantly (P < 0.05) depressed by dietary Nutrafos 3, especially at the highest level of inclusion. There was no treatment effect on egg size as well as some major anatomical characteristics. The best overall performance was achieved at the 3.5% level of dietary inclusion in contrast to the proprietary recommendation of 2.5%.

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