A comparison of the efficiency of food utilization for egg production of some inbred lines of Brown Leghorn fowls

1960 ◽  
Vol 55 (2) ◽  
pp. 241-245 ◽  
Author(s):  
W. Bolton
Keyword(s):  
Egg Production ◽  
Egg Size ◽  
Analytical Data ◽  
Inbred Lines ◽  
Standard Errors ◽  
Food Utilization ◽  
Food Conversion ◽  
Egg Weight ◽  
Egg Number

1. The efficiency of food conversion of Brown Leghorn fowls inbred for egg number, or egg size, or egg number and egg size have been compared.2. Comparison between the lines was made for egg numbers, total egg weight and total egg energy. Egg energy was the best measure of production, total egg weight was the next best and egg number the poorest.3. When allowance was made for differences in rates of egg production and egg size, there were no differences in the efficiency of conversion of food to eggs between the lines.4. The standard errors of the means for the analytical data on the twelve replicate mixes of the diet were relatively small, but the range in values was appreciable. The importance of analysing diets in nutrition experiments is stressed, particularly for ‘iso-caloric’ diets.

Genetic parameters for egg weight v. age curve, and other egg production and egg weight traits, in synthetic lines of chickens

1983 ◽  
Vol 34 (1) ◽  
pp. 85 ◽  
Author(s):  
BH Yoo ◽  
BL Sheldon ◽  
RN Podger
Keyword(s):  
Standard Deviation ◽  
Genetic Correlation ◽  
Egg Production ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Egg Mass ◽  
Control Line ◽  
Egg Weight ◽  
Egg Number ◽  
Selection For

An exponential curve, W = P-Qexp(- Rt), where W is egg weight at age t, was fitted to egg weights of individual pullets, and genetic parameters were estimated for P, Q and R, the residual standard deviation and other egg weight and egg production characters. The data consisted of records collected over six generations on more than 4000 pullets in two selection lines and a control line which originated from a synthetic gene pool of White Leghorn x Australorp crosses. The half-sib and offspring-on-parent regression estimates of heritability pooled over the lines were 0.23 and 0.33 for P, 0.14 and 0.20 for Q, and 0.14 and 0.25 for R. Genetic correlations were estimated to be -0.10 between P and Q, -0.46 between P and R, and 0.90 between Q and R. These estimates suggest that the egg weight v. age curve may be modified to increase the proportion of eggs in desirable weight grades and reduce the incidence of oversized eggs later in the production year. The genetic correlation between mean weight of first 10 eggs and egg weight at 62 weeks of age was estimated to be 0.68, further suggesting that early egg weight may be improved partly independently of late egg weight. The heritability estimates of egg mass output were not higher than those of egg number in spite of the highly heritable average egg weight being an important component of egg mass, probably because of the negative genetic correlation (r = -0.49) between egg number and average egg weight. The standard deviation of individual pullet's egg weights was moderately heritable and genetically correlated positively with egg weight characters and negatively with egg production; these estimates were consistent with the responses to selection for reduced egg weight variability observed elsewhere

Performance of laying hens fed on diets containing heat-treated beans (Vicia faba L. var. minor), cotyledons and hulls

1980 ◽  
Vol 95 (3) ◽  
pp. 697-701
Author(s):  
G. Olaboro ◽  
L. D. Campbell ◽  
R. R. Marquardt
Keyword(s):  
Heat Treatment ◽  
Vicia Faba ◽  
Egg Production ◽  
Egg Size ◽  
Laying Hens ◽  
Body Weight Gain ◽  
Productive Performance ◽  
Egg Weight ◽  
Heat Treated ◽  
Vicia Faba L

SUMMARYTwo experiments were conducted to study the influence of heat treatment of Vicia faba beans on the productive performance of laying hens fed diets containing large proportions of the beans. In the first experiment, the effects of extruding and pelleting the beans were studied while in the second experiment the effects of autoclaving at 121 °C for 30 min the cotyledons and hulls of the beans were evaluated. Hyline-W36 layers were used in the first experiment while two strains (Shaver-288 and Dekalb) of birds were used in the second experiment. Each experiment lasted 5 months during which data on egg production, egg weight, feed intake, mortality and body-weight gain of birds were collected. The results obtained indicated that heat treatment (extruding, pelleting and autoclaving) of the beans, cotyledons and hulls had no beneficial effect on the productive performance of laying hens fed on diets containing large proportions of the heated beans, cotyledons and hulls. Egg-size reducing factors appeared to be concentrated in the cotyledons rather than the hulls of the beans.

Intraspecific variation in reproductive effort by female Parapediasia teterrella (Lepidoptera: Pyralidae) and its relation to body size

1990 ◽  
Vol 68 (1) ◽  
pp. 44-48 ◽  
Author(s):  
Larry D. Marshall
Keyword(s):  
Life History ◽  
Body Size ◽  
Egg Production ◽  
Egg Size ◽  
Reproductive Effort ◽  
Life History Evolution ◽  
Reproductive Parameters ◽  
Trade Offs ◽  
Egg Number ◽  
Lepidoptera Pyralidae

Daily egg production of the moth Parapediasia teterrella declined over the life-span of the female but egg size remained constant. The absence of water resulted in lower fecundity and early mortality. Egg size and lifetime fecundity showed considerable inter-individual variation and large females produced more and larger eggs than their smaller counterparts. Large females expended greater reproductive effort than small females. Hatching success was negatively related to egg size. In spite of this, large females laying large eggs had higher fitness than small females. I postulate that multiple reproductive strategies within a species, resulting from differences in reproductive effort expended, may explain why expected trade-offs in reproductive parameters (e.g., egg size versus egg number) were not found in this species. Furthermore, I argue that the prevalent interpretation of life-history evolution (that body size is the important determining parameter of life-history parameters) may reflect correlation of body size with reproductive effort, and reproductive effort may be more important in determining the nature of trade-offs between reproductive parameters.

Performance of laying hens as affected by the supplementation of a barley-based diet with a crude enzyme preparation from Trichoderma viride

1994 ◽  
Vol 74 (1) ◽  
pp. 129-133 ◽  
Author(s):  
J. Brufau ◽  
R. Cos ◽  
A. Pérez-Vendrell ◽  
E. Esteve-Garcia
Keyword(s):  
Water Consumption ◽  
Egg Production ◽  
Egg Size ◽  
Laying Hens ◽  
Trichoderma Viride ◽  
Feed Consumption ◽  
Egg Weight ◽  
Crude Enzyme Preparation ◽  
Enzyme Supplementation ◽  
Enzyme Supplement

Two experiments were conducted to compare the performance of Leghorn hens fed a barley-based diet (68.93%) containing three levels of a Trichoderma viride enzyme supplement (0, 100 and 200 mg kg−1 as treatments T2, T3 and T4, respectively) with those obtained when fed a corn-based diet (Treatment T1). In exp. 1, 80 hens were used to determine performance during four 28-d periods, between 21 and 37 wk of age. Egg production, feed consumption, feed efficiency and egg weight of the hens were not affected by enzyme supplement and were similar to those of hens fed the corn diet (P > 0.05). There were also no significant effects on feed consumption per gram of egg or per bird per day (P > 0.05). There was a significant interaction for egg weight between enzyme addition and periods (P < 0.034), indicating that enzyme supplementation improved egg size in the early periods. In exp. 2, 20 hens were fed the same diets to measure water consumption and the ratio of water to feed consumption. Water consumption was not affected (P < 0.07) but the ratio of water to feed was significantly reduced (P < 0.0005) when enzyme was added to the barley-based diet. Water consumption in g d−1 was 172 for T1, 215 for T2, 211 for T3, and 195 for T4, and the water to feed ratios were 1.40, 1.85, 1.66, and 1.56, respectively. These results demonstrate that barley can replace corn in layer diets and that the addition of enzyme to barley-based diets appears to improve egg size and to reduce water consumption relative to feed intake in young laying hens. Key words: Laying hens, performance, water consumption, β-glucans, enzyme supplementation

The reproductive effort of Lepeophtheirus pectoralis (Copepoda: Caligidae): insights into the egg production strategy of parasitic copepods

Parasitology ◽  
2015 ◽  
Vol 143 (1) ◽  
pp. 87-96 ◽  
Author(s):  
D. G. FRADE ◽  
M. J. SANTOS ◽  
F. I. CAVALEIRO
Keyword(s):  
Egg Production ◽  
Egg Size ◽  
Reproductive Effort ◽  
Parasitic Copepods ◽  
Egg Number ◽  
Production Strategy ◽  
European Flounder ◽  
Fish Hosts ◽  
First Time ◽  
The Relationship

SUMMARYThe reproductive effort of Lepeophtheirus pectoralis (Müller O. F., 1776), a caligid copepod, which is commonly found infecting the European flounder, Platichthys flesus (Linnaeus, 1758), is studied in detail for the first time. Seasonal variation in body dimensions and reproductive effort are analysed. Data for 120 ovigerous females, 30 from each season of the year, were considered in the analyses. Females were larger and produced a larger number of smaller eggs in winter, than during the summer. The relationship between egg number and egg size is similar to that recorded for other copepods exploiting fish hosts. Much of the recorded variation was also similar to that reported for a copepod parasitic on an invertebrate host, which suggests the possibility of a general trend in copepod reproduction. Overall, our results provide further support for the hypothesis that there is an alternation of summer and winter generations.

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

2021 ◽  
Vol 1 (1) ◽  
pp. 36-41
Author(s):  
MD. Ruhul Amin ◽  
Elliyana Nadia Hamidi
Keyword(s):  
Body Weight ◽  
Egg Production ◽  
Egg Size ◽  
Basal Diet ◽  
Experimental Period ◽  
Egg Mass ◽  
Egg Weight ◽  
Treatment Groups ◽  
Microbial Phytase ◽  
Production Group

 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<0.05) among the treatment groups but level of phytase did not affect (p<0.05) body weight of hens. Both HHEP and EW were in order of 2.5>1.5>0 g/kg feed phytase group and all the means were significantly (p<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.

Estimation of genetic parameters of growth and egg production traits by animal model in IWK layer strain

2019 ◽  
Author(s):  
P. Chandan ◽  
T.K. Bhattacharya ◽  
U. Rajkumar ◽  
L.L.L. Prince ◽  
R.N. Chatterjee
Keyword(s):  
Animal Model ◽  
Body Weight ◽  
Egg Production ◽  
Heritability Estimate ◽  
The Body ◽  
Production Traits ◽  
Economic Traits ◽  
Egg Weight ◽  
Egg Number ◽  
Highly Correlated

Indian White Leghorn strain-IWK has been improved for higher egg weight as well as number over last twelve generations at ICAR-Directorate of Poultry Research, Hyderabad. The data collected on various economic traits of egg production were analyzed using REML approach of animal model. Current study showed that the heritability estimate of body weight, age at sexual maturity (ASM), egg numbers and egg weight was moderate to high, low to moderate, low and high, respectively. The body weight was positively correlated with egg weight but negatively correlated with egg numbers. The body weight at 16 and 20 weeks were negatively correlated with ASM and were very important for achieving early ASM. ASM was negatively correlated with egg numbers. The egg weight regressed as the egg number increased. The part period egg production EP52 was highly correlated with EP64; therefore EP52 can be used for selecting parents for higher egg number instead of EP64.

scholarly journals Direct and correlated responses to selection in two flocks of White Leghorn

1999 ◽  
Vol 42 (4) ◽  
pp. 403-414
Author(s):  
G. S. Brah ◽  
M. L. Chaudhary ◽  
J. S. Sandhu
Keyword(s):  
Egg Production ◽  
Production Efficiency ◽  
Efficiency Index ◽  
Egg Mass ◽  
Control Line ◽  
Correlated Responses ◽  
Egg Weight ◽  
Egg Number ◽  
Realized Genetic Gains ◽  
D 20

Abstract. Data on 17,588 pulletes of two strains selected for egg number and egg weight along with a control line were examined over seven generations. Significant desirable realized genetic gains/generation were observed for egg number to 40 weeks (2.18 and 2.23 eggs) and egg weight (0.81 and 0.45g) in both the strains. Significant correlated responses were also observed in age at first egg (−1.54 and −1.17 d); 20 and 40 week body weights (8.8 to 19.0). Significant desirable responses were also observed for egg mass (175 and 151g), rate of lay (1.0 and 1.37%), egg production efficiency (0.08 and 0.07) and efficiency index (1.09 and 1.03 g/d/kg) Natural selection did not seem to play any role. Inbreeding of 0.28 to 0.45% per generation did not appear to be of any significance in affecting the performance and heritabilities. The additive genetic and phenotypic variances and heritabilities remained stable over generations. Realized heritabilities varied between 0 18 and 0.29 for egg number and between 0.44 and 0.66 for egg weight and indicated the effectiveness of the criterion of selection.

Egg production and quality: effects of vicia faba in laying hen diets

1992 ◽  
Vol 1992 ◽  
pp. 84-84
Author(s):  
J. R. Scaife ◽  
Abeba Amare ◽  
T. Acamovic ◽  
W. Michie ◽  
M. Davis
Keyword(s):  
Vicia Faba ◽  
Egg Production ◽  
Protein Digestibility ◽  
Quality Parameters ◽  
Laying Hen ◽  
Egg Weight ◽  
The World ◽  
Egg Number ◽  
Farm Livestock

Vicia faba has considerable potential as a protein supplement for farm livestock in many parts of the world. The protein content varies depending on cultivar but has been reported to range from 230 - 390 g/kg (Garrido et al 1991) The extensive use of vicia faba in laying hen diets has been limited by the, presence antinutrients such as tannins, lectins and pyrimidine glucosides which have been reported to decrease protein digestibility (Lacassagne et al. 1988) and adversely affect egg production and quality parameters such as egg number and egg weight (Guillume et al 1977). The production of low tannin cultivars of vicia faba has increased interest in its use in poultry feeds and an experiment was conducted to investigate the effects on egg production and quality of inclusion of whole ground beans; cotyledons or hulls from one such low tannin cultivar ‘Toret’.

Egg production and certain behavioural characteristics and mortality pattern of indigenous chicken of India

2016 ◽  
Vol 59 ◽  
pp. 27-36
Author(s):  
P.G. Kumar ◽  
R.R. Churchil ◽  
A. Jalaludeen ◽  
K. Narayanankutty ◽  
P.A. Peethambaran ◽  
...  
Keyword(s):  
Sexual Maturity ◽  
Egg Production ◽  
Egg Mass ◽  
Indigenous Chicken ◽  
Mortality Pattern ◽  
Egg Weight ◽  
Behavioural Characteristics ◽  
Body Weights ◽  
Egg Number ◽  
Production Characteristics

Summary A survey to document the behaviour characteristics and mortality pattern of indigenous chicken of Kerala and a field egg recording study to record egg production characteristics of these birds were conducted. Flight distance and height was 13.29 and 3.97 m, respectively. The territory radius of cocks was 121.15 m. The chick survivability at 4 weeks of age was 64.98 percent. The day-old and 8th week body weights were 28.83 and 347.24 g, respectively. The 20th and 40th week body weight of males were 1,428.42 and 1,936.67 g and that of females were 1,114.04 and 1,445.63 g, respectively. The mortality up to 72 weeks was 69.38 percent and major cause of mortality during chick, grower and layer stage were mongoose (44.63 percent), wolf (24.29 percent) and diseases (52.18 percent) respectively. The fertility was 71.22 percent and hatchability on total and fertile egg set were 62.26 and 87.42 percent, respectively. There were 2.13 clutches in a laying cycle with inter-clutch intervals of 1.11 days. The average clutch size and number of eggs per cycle were 7.27 and 14.32, respectively. The egg number up to 72 weeks on hen-day and hen-housed basis was 116.81 and 85.84, respectively and the eggs were laid in 7.7 cycles. The age at first egg and average age at sexual maturity were 155 and 199.26 days, respectively. The egg weight at 28, 40 and 72 weeks of age was 37.80, 40.74 and 43.31 g, respectively, and egg mass per bird was 4,659.04 g. The broodiness and incubation pause were 26.03 and 121.75 days, respectively.

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