scholarly journals Effect of genotype, age of hens and K/k allele on eggshell quality

2011 ◽  
Vol 56 (No. 5) ◽  
pp. 242-249 ◽  
Author(s):  
Z. Ledvinka ◽  
L. Zita ◽  
M. Hubený ◽  
E. Tůmová ◽  
M. Tyller ◽  
...  
Keyword(s):  
Growth Rate ◽  
Egg Production ◽  
Statistical Significance ◽  
Live Weight ◽  
Shape Index ◽  
Feed Mixture ◽  
Eggshell Quality ◽  
Feather Growth ◽  
Two Factors ◽  
The Relationship

We assessed the influence of the particular genotype, age of layers, feather growth-rate gene, and their mutual interactions on selected indicators of eggshell quality in six groups of hens of the laying type Dominant. The following genotypes were examined in the experiment: Barred Plymouth Rock, Dominant BPR 951 (K) strain, slow-feathering; Barred Plymouth Rock, Dominant BPR 901 (k) strain, fast-feathering; Blue Plymouth Rock, Dominant BLPR 954 (K) strain, slow-feathering; Blue Plymouth Rock, Dominant BLPR 894 (k) strain, fast-feathering; crossbreds of the above strains in the F<sub>1</sub> generation Dominant D 107 blue (K), slow-feathering and Dominant D 107 blue (k), fast-feathering. The layers were fed a feed mixture NP1 (16.64 % CP) from the 20<sup>th</sup> week of age and a feed mixture NP2 (15.02% CP) from the 42<sup>nd</sup> week. Husbandry conditions met the regular requirements of laying hens. Egg production and live weight of hens were monitored for the duration of the experiment (12 months). Eggshell quality was examined at the layers' age of 27, 35 and 56 weeks. The average hen-day egg production for the duration of the experiment (12 months) was not significantly influenced by the particular genotype or the feather growth-rate gene. The varying representation of the feather growth-rate gene significantly (P &le; 0.001) influenced the live weight; similarly, the relationship between the genotype and the representation of K/k alleles was significant. The average egg weight was influenced statistically significantly (P &le; 0.001) by the age of hens, their genotype (P &le; 0.05), feather growth-rate gene (P &le; 0.001), and the relationship between the age and genotype (P &le; 0.001). The age of hens, genotype, and the interaction of these two factors affected the egg shape index, as did the incidence of the feather growth-rate gene within the population (with a statistical significance of P &le; 0.001). The age, genotype and the feather growth-rate gene incidence within the population also significantly affected the eggshell quality indicators. In the eggshell to egg ratio, eggshell thickness and strength, an interaction was determined between the age of hens and their particular genotype. The eggshell colour was also significantly (P &le; 0.001) affected by hens' age, genotype (P &le; 0.001), as well as by the feather growth-rate gene (P &le; 0.001). No significant interaction between the age and the genotype was found for this indicator.

Selection on ram 18-month weight to improve lamb growth rate

1983 ◽  
Vol 36 (2) ◽  
pp. 159-164
Author(s):  
D. Croston ◽  
J. L. Read ◽  
D. W. Jones ◽  
D. E. Steane ◽  
C. Smith
Keyword(s):  
Growth Rate ◽  
Live Weight ◽  
Indirect Selection ◽  
Direct Selection ◽  
Selection For ◽  
The Relationship ◽  
Lamb Growth

ABSTRACTThirteen pairs of Suffolk rams were selected on high and low 18-month adjusted live weight from six farms over 2 years, to establish the relationship between 18-month weight and early lamb growth. Progeny were first produced in recorded crossbred flocks (618 lambs) and then in an experimental flock of crossbred ewes (1083 lambs). Different results were obtained from the recorded and experimental flocks. The regressions of lamb 12- to 13-week weight on ram 18-month weight (within farm deviation) were 0·053 ± 0·022 kg and –0·004 ± 0·020 kg, respectively. These regressions for indirect selection correspond to ‘effective’ heritabilities for direct selection for lamb growth of 0·18 ± 0·07 and 0·02 ± 0·06 respectively. Improvement of early Iamb growth is discussed and it is concluded that selection for 18-month weight is unlikely to be a useful method.

The intensive rearing of lambs 2. Voluntary food intake and performance on diets of varying oat husk and beef tallow content

1967 ◽  
Vol 9 (4) ◽  
pp. 509-520 ◽  
Author(s):  
J. B. Owen ◽  
D. A. R. Davies ◽  
E. L. Miller ◽  
W. J. Ridgman
Keyword(s):  
Growth Rate ◽  
Food Intake ◽  
Beef Tallow ◽  
Live Weight ◽  
Physical Form ◽  
Intensive Rearing ◽  
Pelleted Diet ◽  
And Performance ◽  
Oat Husk ◽  
The Relationship

1. Two experiments concerned with the voluntary intake of food by artificially reared lambs are described and the results discussed.2. When the diets were pelleted the addition of finely ground oat husks to form as much as 40% of the diet had practically no effect on live weight gain since the lambs controlled their consumption to achieve the same energy intake on the various diets. When the diets were given as a meal, the addition of 20% oat husks caused food intake to increase, digestible dry-matter intake to remain the same and growth rate to be somewhat poorer; but the addition of 40% oat husks caused no further increase in intake so that digestible drymatter intake fell markedly and growth rate was much reduced. It is argued that the relationship between food intake and digestibility is dependent on the physical form of the diet.3. Addition of beef tallow to the meal diets had very little effect on the lambs' performance.4. Lambs which had received a restricted quantity of milk replacer from birth to 11·4 kg live weight had a slower growth rate and poorer food conversion efficiency during the subsequent feeding period (13·6–34·1 kg) than lambs which had received milk ad libitum. This effect was greater with meal diets containing 40% oat husks than with more concentrated diets.5. On a pelleted diet containing 85% barley a conversion ratio of 3·21 was achieved over the whole fattening period, indicating the commercial feasibility of intensive lamb production on cereal diets.

scholarly journals Administration of Clinoptilolite to Broiler Chickens During Growth and Its Effect on the Growth Rate and Bone Metabolism Indicators

2008 ◽  
Vol 77 (2) ◽  
pp. 199-207 ◽  
Author(s):  
E. Straková ◽  
R. Pospíšil ◽  
P. Suchý ◽  
L. Steinhauser ◽  
I. Herzig
Keyword(s):  
Growth Rate ◽  
Bone Metabolism ◽  
Broiler Chickens ◽  
Dry Matter ◽  
Live Weight ◽  
Ash Content ◽  
Feed Additive ◽  
Feed Mixture ◽  
Calcium Phosphorus ◽  
Experimental Group

The growth rate and bone metabolism indicators were monitored in broiler chickens receiving the feed supplemented with clinoptilolite. One-day-old broiler chickens ROSS 308 were divided into control (C) and experimental (E) groups with 100 males and 100 females per group. The chickens received the complete feed mixture BR1 from 1 to 10 days of age, followed by the feed mixture BR2 until the age of 30 days, and the feed mixture BR3 until the end of the experiment (40 days). The feed mixtures of the experimental group were supplemented with clinoptilolite (commercial additive ZeoFeed) at a level of 0.5% (BR1), 1.5% (BR2) and 2.5% (BR3), replacing the corresponding portion of wheat. Feed mixtures and drinking water were provided ad libitum. The live weight of broiler chickens in both the control and experimental group increased steadily during the experiment. At the end of the experiment, live weights of experimental females (2,416 g) and males (2,829 g) were higher than those of control females (2,345 g) and males (2,694 g) by 3% and 5%, respectively. Significant differences in the live weight between groups were found from the age of 30 days (P ⪬ 0.05 and P ⪬ 0.01). At the age of 40 days, the chickens were slaughtered and the femur and tibiotarsus of the right leg were analysed for the content of dry matter, ash, calcium, phosphorus and magnesium. The ash content in dry matter ranged from 53.0 to 54.1% in group C and from 51.7 to 53.2% in group E. The Ca and P contents in dry matter in group E were lower than those in group C, except for Ca and P in the male tibiotarsus. In both groups, regardless of sex, the ash content was higher in the tibiotarsus than in the femur. Since fat levels in bones of the experimental group were increased (females by 19.5% in the femur and 21.3% in the tibiotarsus; males by 22.0% in the femur and 26.3% in the tibiotarsus), which could affect the values obtained, ash, calcium, phosphorus and magnesium were determined in the fat-free dry matter. The trends found in the originally determined dry matter were maintained, i.e. lower levels of ash, Ca, and P in the experimental group, except for male Ca in both kinds of bones. The corresponding levels in the fat-free dry matter were relatively higher as compared to the original dry matter. The results of the study showed that up to 2.5% of clinoptilolite in the diet had no adverse effect on performance and bone metabolism indicators of growing broiler chickens. Thus, it can be used as a suitable feed additive to broiler diets due to its positive effect on nutrient utilization, mechanism of digestion and pollutant elimination in connection with food safety issues.

scholarly journals The effect of growth and development intensity in replacement heifers on economically important traits of Holstein cattle in the Czech Republic

2008 ◽  
Vol 52 (No. 9) ◽  
pp. 277-283 ◽  
Author(s):  
J. Bouška ◽  
M. Štípková ◽  
M. Krejčová ◽  
L. Bartoň
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Growth And Development ◽  
Live Weight ◽  
The Other ◽  
Total Production ◽  
Live Weight Gain ◽  
Productive Life ◽  
Reproduction Traits ◽  
The Relationship

The objective of the study was to determine the effect of growth and development intensity in Holstein replacement heifers on economically important animal traits. The intensity of growth was assessed by the average live weight gain until 14 months of age. In addition, live weight and height at the sacrum at 14 months of age were analysed as indicators of growth and development when evaluating the length of productive life. The milk yield of first-calvers increased as the average daily live weight gain in the rearing period increased. An opposite tendency was recorded for cows in their second and third lactation and the total production also decreased with a higher growth rate of heifers. The analysis of the relationship between growth rate and the following reproduction traits revealed that the increased average daily live weight gain to 14 months was subsequently associated with reduced reproduction efficiency in cows. The differences between the groups with the lowest and the highest average live weight gains in the number of days open in the first and second calving interval were 26.78 and 17.47 days, respectively. This tendency was also confirmed in the other reproduction traits analysed. Productive life was significantly longer in animals with the lowest intensity of growth and development compared to the other groups (2.17 to 5.49 months, <i>P</i> < 0.01).

The effect of herbage allowance on herbage intake and performance of lambs grazing perennial ryegrass and red clover swards

1976 ◽  
Vol 86 (2) ◽  
pp. 355-365 ◽  
Author(s):  
M. J. Gibb ◽  
T. T. Treacher
Keyword(s):  
Growth Rate ◽  
Organic Matter ◽  
Perennial Ryegrass ◽  
Nitrogen Fertilizer ◽  
Daily Intake ◽  
Live Weight ◽  
Red Clover ◽  
Asymptotic Curves ◽  
Digestible Organic Matter ◽  
The Relationship

SummaryThe effect of daily herbage allowance on herbage intakes and growth rates lambs grazing perennial ryegrass and red clover was investigated in two experiments. Herbage allowances defined as g herbage D.M./kg live weight (LW)/day were controlled by varying the areas of plots grazed for 2 days by groups of six lambs.In the first experiment five herbage allowances in the range 20–120 g D.M./kg LW/day were offered on two areas of a perennial ryegrass (cv. S. 23) sward that received nitrogen fertilizer applications of 39 or 78 kg N/ha/28 days. In the second experiment five herbage allowances in the range 30–160 g D.M./kg LW/day were offered on perennial ryegrass (cv. S. 23) and red clover (cv. Hungaropoly) swards.Asymptotic curves were fitted to describe the relationship between herbage allowance and daily intake of herbage. In Expt 1 nitrogen fertilizer rates did not affect the yield of herbage or animal performance. In Expt 2 intakes were higher on the clover sward than on the ryegrass sward at the higher herbage allowances.The asymptotic curves to describe the relationship between herbage allowance and growth rate of lambs differed widely between periods. Growth rate of the lambs increased linearly with increase in digestible organic matter intake. Live-weight gain per unit of digestible organic matter intake was higher on the red clover than on the ryegrass.The conclusion is drawn that if the herbage present to ground level is not more than three times the daily intake of the animals, intake of herbage of the animals may bo restricted.

The effect of growth rate on muscle distribution in sheep

1975 ◽  
Vol 85 (1) ◽  
pp. 189-191 ◽  
Author(s):  
D. M. Murray ◽  
Olga Slezacek
Keyword(s):  
Growth Rate ◽  
Weight Loss ◽  
Growth Rates ◽  
Live Weight ◽  
High Growth ◽  
Growth Path ◽  
Merino Sheep ◽  
Reported Data ◽  
Relationship Of ◽  
The Relationship

There is little information available on the effect of growth rate on muscle distribution in sheep. Although Lohse, Moss & Butterfield (1971) and Lohse (1973) have reported data on muscle distribution of Merino sheep, the growth rates of animals in both these studies were neither controlled nor reported. In another experiment using Merino sheep, Lohse, Pryor & Butterfield (1973) studied the effect of a period of live-weight loss on the relationship of selected muscles to total side muscle during subsequent re-alimentation. They found that the interrupted growth path decreased the proportion of total side muscle formed by the weight of ten muscles which had previously been classified as muscles with a high growth impetus (Lohse, 1971). Data are presented herein for the muscle distribution of sheep grown along three growth paths.

A study of the relationship between plane of nutrition during lactation and certain production characteristics in autumn-calving suckler cows

1983 ◽  
Vol 37 (3) ◽  
pp. 353-363 ◽  
Author(s):  
S. H. Somerville ◽  
B. G. Lowman ◽  
R. A. Edwards ◽  
G. Jolly
Keyword(s):  
Growth Rate ◽  
Compensatory Growth ◽  
Live Weight ◽  
Beef Cows ◽  
Metabolizable Energy ◽  
Condition Score ◽  
The Mean ◽  
Daily Intakes ◽  
The Relationship ◽  
Production Characteristics

ABSTRACTHereford ♂ × British Friesian ♀ cows that had calved in September/October and were suckling mainly Charolais ♂ × calves were offered individually one of three planes of nutrition based on their estimated maintenance requirement during their first 150 days of lactation.The mean daily intakes of metabolizable energy were 95·8, 71·5 and 52·1 MJ for the high, medium and low planes of nutrition respectively. Data were collected from 122 lactations. The mean 150-day cumulative milk yields of the cows were 1 355, 1 258 and 1 187 kg for the high, medium and low planes of nutrition respectively (P < 0·001). A i-kg increase in calf birth weight was associated with an increase in 150-day cumulative milk yield of 14·7 ± 2·17 kg (P < 0·001). Losses in live weight and condition score were significantly greater for cows given the low plane of nutrition during lactation (P < 0001).Although there was a significant (P < 0·01) positive correlation between the growth rate of the calves and their dams' nutritional level during the winter there was evidence of compensatory growth at grass, since by the time of weaning in August, the plane of nutrition of the dam during the winter had no significant effect on the weight of the calves.The experiment demonstrates that energy-deficient beef cows will attempt to maintain milk production at the expense of body reserves and that when supplementary solid food is made available to the suckled calves, their weaning weights are unaffected by the plane of nutrition of the dam during the winter.

Milk-fed calves: 3. The milk intake, herbage intake and performance of suckled calves

1976 ◽  
Vol 87 (1) ◽  
pp. 205-211 ◽  
Author(s):  
Y. L. P. Le Du ◽  
R. D. Baker ◽  
J. M. Barker
Keyword(s):  
Growth Rate ◽  
Milk Production ◽  
Live Weight ◽  
Milk Intake ◽  
Milk Consumption ◽  
Herbage Intake ◽  
Consequent Effect ◽  
And Performance ◽  
The Relationship ◽  
Friesian Cows

SUMMARYTwo trials were conducted to measure the herbage intake of South Devon cross calves suckling Hereford × Friesian cows and to test the validity of applying the relationships established between milk and herbage intake and milk intake and live-weight gain for artificially fed calves to suckled calves. In Expt 1 the milk and herbage intakes of eight calves were monitored. Their average milk consumption was 2250 kg and their growth rate was 1·14 kg/day. Both milk consumption and growth rate were higher than those recorded in other studies with artificially-reared calves. Nevertheless, it was possible to predict the herbage intake and growth rate of the calves from the relationship previously established for artificially reared calves. The nutrition of cows in Expt 2 was manipulated to induce changes in milk production and the consequent effect on the herbage intake of their calves assessed. Milk consumption was at a lower level and herbage intakes fell within the expected range. Herbage intake also responded to changes in the milk production of the cows. The observed herbage intakes and live-weight gains were similar to those predicted from previously established relationships with artificially fed calves.

Effect of pasture growth rate on live-weight gain of grazing beef cattle

1984 ◽  
Vol 102 (2) ◽  
pp. 265-268 ◽  
Author(s):  
J. P. Ebersohn ◽  
K. W. Moir
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Beef Cattle ◽  
Live Weight ◽  
Energy Concentration ◽  
Dietary Energy ◽  
Live Weight Gain ◽  
Voluntary Intake ◽  
The Relationship ◽  
Differential Contribution

SummaryLive-weight gain of beef cattle grazing all-grass or grass-clover pastures, details of which have been reported previously, was significantly (P < 0·01) correlated with pasture growth rate, but not with pasture dry matter on offer (either total or green), or with dietary-energy concentration. From ideas generated from the relationship between live-weight gain and pasture growth rate, and using intake values measured from the number and size of prehension bites, it is shown how high live-weight gain for measured dietary-energy concentration could be explained by differential contribution to digestibility and voluntary intake from pasture new growth.

Environmental and managerial factors affecting the growth of Friesian heifers from six months of age to calving

1968 ◽  
Vol 71 (1) ◽  
pp. 81-90 ◽  
Author(s):  
B. Ridler ◽  
W. H. Broster
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Early Pregnancy ◽  
Compensatory Growth ◽  
Low Cost ◽  
Live Weight ◽  
Factors Affecting ◽  
Live Weight Gain ◽  
Coefficients Of Variation ◽  
The Relationship

SummaryThe growth of 120 Friesian heifers born into one herd over a period of 12 years was studied for the period from 6 months of age to calving at about 30–35 months of age. Live weights were recorded weekly and rates of live-weight gain were calculated for each 3-month period for each animal. Δt 6, 12, 18, and 24 months of age the heifers weighed 360, 590, 800 and 950 lb. The coefficients of variation of live weight did not vary with age and averaged ±10·0%. Coefficients of variation of live-weight gain increased from ± 20% at 6–9 months of age to ±60% at 24–27 months of age. Growth rate declined by 0·02 lb/day from 12 months to 30 months of age for animals under constant managerial conditions. Heifers wintered indoors grew faster than those wintered outdoors. The growth of younger animals was decreased more by outdoor wintering (a reduction of 0·6 lb/day at 15 months) than was the growth rate of older animals (a reduction of 0·3 lb/day at 21 months of age). When live-weight gain was low in winter there was marked compensatory growth at grass the following summer. Pregnant heifers grew 0·1 lb/day faster in early pregnancy and 0·6 lb/day faster in the last 4 months of pregnancy than did barren heifers.There was no appreciable difference between the live-weight gain of spring- and autumn-born heifers. With an autumn calving policy spring-born heifers were served and conceived 135 days earlier and weighed 106 lb less at calving than did autumn-born heifers. There was little difference in the milk yield of the two groups in 305 days of the first lactation.The regression equation of live weight (lb) on age (months) to 3rd calving was W = 1449 – 2027 e-0·042t. It was concluded that in the interests of economic rearing the dairy farmer could with advantage exercise greater control of the relationship between nutrition and growth during high cost winter periods and low cost summer periods.

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