Genetic studies of South Australian Merino sheep. I. Genetic change in fleece and body traits

1981 ◽  
Vol 32 (4) ◽  
pp. 641 ◽  
Author(s):  
IP Gregory ◽  
RW Ponzoni
Keyword(s):  
Body Weight ◽  
Genetic Change ◽  
Genetic Studies ◽  
Genetic Changes ◽  
Qualitative And Quantitative ◽  
Body Weights ◽  
The Mean ◽  
Fleece Weight ◽  
Linear Regressions ◽  
Selection Differentials

During the years 1953-67 one flock of South Australian Merinos was selected on clean fleece weight (the Index flock) and another on the basis of visual appraisal (the Visual flock). A large number of qualitative and quantitative traits were recorded. Linear regressions of differences between flock means on time were estimated for each trait; not many of the regressions were significant. However, greasy and clean fleece weights of Index animals increased significantly faster than those of Visual animals, and body weights of Visual animals increased significantly faster than those of Index animals. Realized selection differentials were estimated for all traits. There were significant selection differentials for greasy and clean fleece weights and yield in the Index flock, and for body weight and greasy fleece weight in the Visual flock. The response to selection was estimated for all traits by using two methods; regression of the trait on an individual's generation number, and comparison of the deviation from the overall mean of the mean of the progeny of a 3+-year-old sire with the deviation of the progeny of the same sire as a 2+-year-old. The estimate of genetic change in body weight was higher and genetic changes in clean and greasy fleece weights lower in Index animals, which was in contrast with an earlier result. However, when the least-squares means of these traits were compared, it was concluded that the Index flock did, in fact, achieve significantly greater responses in greasy and clean fleece weights and a significantly lower response in body weight than the Visual flock. It was therefore considered that, in these particular experiments, both methods of estimating genetic change had serious limitations.

Estimates of genetic and phenotypic parameters of some weight and fleece traits in a coarse-wool breed of sheep

1982 ◽  
Vol 99 (2) ◽  
pp. 277-285 ◽  
Author(s):  
R. A. Guirgis ◽  
E. A. Afifi ◽  
E. S. E. Galal
Keyword(s):  
Body Weight ◽  
Genetic Correlations ◽  
Phenotypic Correlations ◽  
Body Weights ◽  
Heritability Estimates ◽  
Fleece Weight ◽  
Staple Length

SUMMARYA study using 1150 lambs to estimate genetic and phenotypic parameters of some weight and fleece traits was carried out on coarse-wool Barki sheep. The weight traits were birth, weaning, yearling weights and daily gains whereas fleece traits included kemp score, staple length and greasy-fleece weight.Heritability estimates of weight traits were within the range 0·25–0·30. Those of fleece traits were 0·16, 0·21 and 0·43. The repeatability estimates of fleece traits were 0·18, 0·38 and 0·53 for staple length, greasy-fleece weight and kemp score respectively.Phenotypic correlations between body weight and fleece traits were mostly positive. Genetic correlations between greasy-fleece weight and body weights were mostly positive and of medium values. Those between kemp score and body weights were mostly negative, ranging from medium-high to high.

Maintenance rations for Merino sheep. IV. The performance of adult Merino ewes fed daily and weekly at three levels of energy intake

1957 ◽  
Vol 8 (1) ◽  
pp. 75 ◽  
Author(s):  
PK Briggs ◽  
MC Franklin ◽  
GL McClymont
Keyword(s):  
Body Weight ◽  
Sodium Chloride ◽  
Energy Intake ◽  
Survival Rates ◽  
Experimental Period ◽  
The Body ◽  
Merino Sheep ◽  
Wool Production ◽  
Body Weights ◽  
The Mean

Dry adult Merino ewes were fed at daily or weekly intervals on oat grain at levels which provided 4.0, 3.0, or 2.0 lb starch equivalent (S.E.) per sheep per week. The experimental periods were 223, 223, and 181 days respectively. Differences between the mean body weights of the ewes a t the three levels of feeding were highly significant (P < 0.001). Body weight varied only slightly and no losses occurred in ewes fed weekly at the rate of 4.0 lb S.E. per head. Ewes fed daily a t this level had a significantly greater mean body weight (P < 0.001) a t the conclusion of the 223-day experimental period. The addition of a sodium chloride supplement did not improve the body weight or wool production of ewes fed weekly a t the level of 4.0 lb S.E. The mean body weight of ewes fed at the levels of 3.0 or 2.0 lb S.E. per head declined over the first 12 and 18 respectively and thereafter remained relatively constant. There were no significant differences at these levels of feeding between groups fed daily and weekly in respect of body weight, wool production, or survival rates. Ewes fed a t the level of 4.0 lb S.E. grew significantly more wool than those given 3.0 lb S.E. (P < 0.001). Losses were negligible in all groups except those fed a t the level of 2.0 lb S.E. In these groups there were few deaths in the first 16 weeks, but in the subsequent 10 weeks losses totalled 17.1 per cent. Ewes fed a t the level of 2.0 lb S.E. consumed their rations at a significantly slower rate (P < 0.01) than did those fed a t the level of 4.0 lb S.E.

Effect of body weight on the attainment of puberty and reproductive performance of Galway and Fingalway female lambs

1979 ◽  
Vol 28 (3) ◽  
pp. 297-307 ◽  
Author(s):  
J. F. Quirke
Keyword(s):  
Body Weight ◽  
Breeding Season ◽  
Litter Size ◽  
Conception Rate ◽  
Restricted Feeding ◽  
Ewe Lambs ◽  
Younger Age ◽  
Body Weights ◽  
The Mean ◽  
Ad Libitum

ABSTRACTGroups of spring-born Galway (G) and Fingalway (F) ewe lambs were fed a concentrate diet either ad libitum (H) or at a restricted level (L) during the period 25 July to 16 October 1974 in order to induce differences in body weight at the start of the breeding season. The mean live weights of the GL, GH, FL and FH groups on 16 October 1974 were 37·8 ± 1·3, 44·6 ± 1·3, 35·1 ± 1·1 and 41·9 ± 1·2 kg respectively. More than 95% of the lambs in all four groups attained puberty before 28 February 1975. Galway ewe lambs reached puberty later in the breeding season and were older and heavier at puberty than Fingalways. Animals fed ad libitum were heavier at puberty and attained puberty earlier in the season and at a younger age than those on the restricted feeding regime.Both conception rate and litter size were lower in Galways than Fingalways. There was no evidence of any effect of the nutritional treatments on conception rate or litter size. The mean body weights at puberty for ewes which lambed and those which were barren were 41·9 ± 0·49 and 41·5 ± 0·78 kg respectively. The birth weight and growth rate of the progeny of the ewe lambs was similar for the two breeds and was not influenced by the previous nutritional treatment of the dams. The total lamb mortality between birth and weaning was 40·3%, and 72% of all deaths occurred within 48 h of birth. Losses among twins (48%) were particularly heavy.

scholarly journals Relationship between egg weight, hatching weight and subsequent body weight in the Japanese quail

2020 ◽  
Vol 47 (1) ◽  
pp. 19-23
Author(s):  
V. O. Chimezie ◽  
A. A. Ademola ◽  
O. I. Alli ◽  
A. E. Jubril ◽  
B. O. Josiah
Keyword(s):  
Body Weight ◽  
Japanese Quail ◽  
Coefficient Of Determination ◽  
Egg Weight ◽  
Body Weights ◽  
The Mean ◽  
The University ◽  
Large Groups ◽  
The Relationship ◽  
Selection Of

An experiment to determine the relationship between egg weight, hatch weight and subsequent body weight of the Japanese quail was conducted. A total of 607 eggs collected over 6 days from an existing flock at the Animal Pavilion of the University of Ilorin were used for the experiment. Eggs were individually numbered, weighed and grouped into small (S) medium (M) and large (L) sized eggs based on the mean and standard deviation of the eggs. Mean egg weight were correlated and regressed with mean hatch weight and subsequent weight. Average egg weights were 10.23± 0.84g, 8.49± 0.72g and 6.94± 0.93g for the large, medium and small group respectively. The result showed relationship between egg weight and hatch weight were positive and highly significant (P < 0.01) with values of 0.973, 0.977 and 0.967 for small, medium and large groups, respectively. Relationship between hatch weights and weekly body weights were also positive and significant (P<0.01) for the medium and large groups only but decreased with age. Linear regression equation showed a significant coefficient of determination for weekly body weight using the values for small, medium and large egg weight values. The results of the study showed that egg weight can be reliably used for estimating body weight in Japanese quail and may be used as criteria for early selection of Japanese quail for body weight.

scholarly journals A study of factors affecting weight gain among tuberculosis patients under DOTS in district Amritsar

2018 ◽  
Vol 5 (11) ◽  
pp. 4804
Author(s):  
Pooja Sadana ◽  
Harpreet Kaur ◽  
Vishal Verma
Keyword(s):  
Body Weight ◽  
Weight Gain ◽  
Body Weight Gain ◽  
Continuation Phase ◽  
Factors Affecting ◽  
Tuberculosis Patients ◽  
End Of Treatment ◽  
Body Weights ◽  
The Mean ◽  
The Difference

Background: Wasting is a common feature in tuberculosis and treatment is aimed at achieving weight gain in pulmonary tuberculosis patients. The aims and objectives of the study were to study the extent of body weight gain during treatment and to identify the effect of different factors on weight gain among TB patients.Methods: The study was conducted on a total of 326 patients residing in the area of PHC Verka and registered with District Tuberculosis Centre, Amritsar. Weight change was assessed by taking the difference of weight at initial diagnosis and after completion of continuation phase therapy.Results: A total of 228 patients participated in the study. The mean (±SD) body weights (in kg) for the patients were 44.92±12.7 at diagnosis and 48.79±12.9 at the end of treatment. The mean (±SD) weight gain was 3.86±4.55 kgs at the end of treatment. The gain in weight at the end of treatment was associated with supervision of treatment and outcome of the TB patient.Conclusions: The findings showed that there is an association between gain in weight with supervision of treatment and outcome of the TB patient.

Genetic changes generated within the Katanning Merino Resource flocks

2006 ◽  
Vol 46 (7) ◽  
pp. 803 ◽  
Author(s):  
J. C. Greeff ◽  
G. Cox
Keyword(s):  
Body Weight ◽  
Phase 1 ◽  
Fibre Diameter ◽  
Linear Unbiased Prediction ◽  
Genetic Changes ◽  
Breeding Values ◽  
Best Linear Unbiased ◽  
Fleece Weight ◽  
Estimated Breeding Values ◽  
Genetic Trends

Genetic changes for clean fleece weight, fibre diameter and hogget body weight were determined in the Katanning Merino Resource flocks from 1982 to 2004. From 1982 to 1992 genetic trends are presented for individual studs that used mainly subjective classing selection methods (Phase 1) and the genetic trends from 1997 to 2004 demonstrate the genetic changes that can be achieved from using estimated breeding values calculated from best linear unbiased prediction (BLUP) mixed methodology (Phase 2). The results during the first phase show that very few genetic changes occurred in most studs, except for the 4 studs of the Performance Sheep Breeding strain which showed genetic increases in hogget body weight. The genetic trends show that some studs generated change towards their breeding objective, while others show no changes or changes in the opposite direction. In contrast, the use of BLUP estimated breeding values resulted in positive changes in clean fleece weight, fibre diameter and body weight in accordance with the defined breeding objectives.

Patterns of variation in the dry body weight of Calanus finmarchicus in copepodite Stage V during autumn and winter in the Firth of Clyde

1989 ◽  
Vol 69 (1) ◽  
pp. 101-122 ◽  
Author(s):  
H. Grigg ◽  
L. J. Holmes ◽  
S. J. Bardwell
Keyword(s):  
Body Weight ◽  
Dry Weight ◽  
Copepodite Stage ◽  
Calanus Finmarchicus ◽  
Body Volume ◽  
Individual Stage ◽  
Freeze Dried ◽  
Body Weights ◽  
The Mean ◽  
Autumn And Winter

Variations in dry body weight in the Stage V copepodite, associated with the development of the winter generation of Calanus finmarchicus (Gunnerus) in the Firth of Clyde each year were observed from 1978 to 1982, during early October and the middle of January.The Stage V copepodite was dimorphic with respect to body size. Body weights of freeze-dried specimens were measured and form was distinguished using the prosome length. Allometric relationships of the dry weight to length in the two forms were similar, and stable between autumn and winter. From the mean of estimates for all collections, dry body weights of individual Stage V copepodites were proportional to the cube, approximately, of prosome lengths. Proportional coefficients were seasonally variable, but on all occasions these were greater for the large than the small form. Variations in dry weight were directly associated with the distinction between forms in body volume.Collections from October and January encompassed the period between the end of maximal Copepodite V recruitment and the onset of adult recruitment to the winter generation. Over this period, however, the dry body weight in all years decreased relative to length in Copepodite Stage V. This decrease, on average, was by 17% and 23% in the large and small forms respectively. Monthly collections from one population were used to examine these patterns in relation to the development of gonads. Stage V copepodites of both forms were increasing in dry weight during October, but from November were losing weight continuously. Maturation in the majority of these individuals was restrained throughout autumn, abruptly accelerating in winter.

scholarly journals A Relationship Between Sulphur Content of Wool and Wool Production by Merino Sheep

1967 ◽  
Vol 20 (1) ◽  
pp. 153 ◽  
Author(s):  
PJ Reis ◽  
DA Tunks ◽  
OB Williams ◽  
AJ Williams
Keyword(s):  
Body Weight ◽  
Unit Area ◽  
Sulphur Content ◽  
Merino Sheep ◽  
Wool Production ◽  
Weight Index ◽  
Wool Growth ◽  
The Mean ◽  
Fleece Weight ◽  
The Relationship

The sulphur content of wool from 66 Peppin Merino wethers maintained together at pasture was measured in midside staples representing 49 weeks growth. The distribution of sulphur values was normal with a mean of 3�43 % and a range of 3�08-3�92 %. The sulphur content of the wool was inversely related to wool production among these sheep. There were no significant differences in the relationship when wool production was expressed as fleece weight index (F.W.I.), i.e. clean fleece weight/body weight (r = -0�48), as clean fleece weight (r = -0�42), or as wool growth per unit area of skin (r = - 0�37). The mean sulphur content of wool from sheep with the 10 highest values for F.W.I. was 3�27%, compared with a mean of 3 �55% sulphur for wool from sheep with the 10 lowest values for F.W.I.

scholarly journals Selection intensity for milk yield in 1970—1977 in the Finnish Ayrshire

1978 ◽  
Vol 50 (6) ◽  
pp. 445-454
Author(s):  
U. B. Lindström
Keyword(s):  
Milk Yield ◽  
Genetic Gain ◽  
Genetic Change ◽  
Selection Intensity ◽  
Genetic Progress ◽  
Generation Interval ◽  
Ayrshire Breed ◽  
The Mean ◽  
Selection Differentials

Selection differentials for sires and dams of bulls taken into AI use in 1970—1977, as well as for sires used in AI, were combined with an estimate of the quality of dams of female replacements to calculate the (predicted) genetic change in milk yield in the Ayrshire breed. In the period the average annual genetic gain was 0.97 % of the mean yield, in the last three years it was c. 1.1 %. The average generation interval was 6.8 years; 8.7 years for the bull sires, 7.4 years for the bull dams and 6.4 years for the cow sires. The bull sires accounted for 42 %, the bull dams for 37 % and the cow sires for only 12% of the total genetic gain. A more rational use of progeny tested and young bulls, combined with a reduction of the generation interval of 15 %, could easily have increased the genetic progress by 20 %.

Body-weight-fleece-weight relationships in a strain of Merino sheep

1956 ◽  
Vol 7 (1) ◽  
pp. 57 ◽  
Author(s):  
PG Schinckel
Keyword(s):  
Body Weight ◽  
Body Surface ◽  
Unit Area ◽  
Merino Sheep ◽  
Wool Production ◽  
Significant Difference ◽  
The Mean ◽  
Fleece Weight ◽  
Relationship Of ◽  
The Relationship

The relationship of body weight to wool production was examined in a flock of Merino sheep of South Australian strain over a period of 7 years. In only one out of 10 groups examined was there a significant correlation between body weight and the amount of clean wool produced per unit area of midside skin. It is concluded that body weight and wool production per unit area of body surface are independent. In all groups there was a highly significant correlation between clean fleece weight and clean wool per unit area of body surface in the midside region. The regression of log fleece weight on log body weight was determined in 15 groups. In no case was the regression coefficient significantly different from 0.60. As the regression of log surface area on log body weight in sheep is of the order of 0.60, it is concluded that wool production is proportional to fleece-bearing surface. The mean regression coefficients of log fleece weight on log body weight, calculated within sire and year groups, were: rams, 0.52 ± 0.056; ewes, 0.61 ± 0.038; wethers, 0.30 ± 0.068. There were no significant differences between sires in the regression of log fleece weight on log body weight. There were, however, highly significant differences between sire groups in mean log fleece weight, after adjustment for differences in log body weight. Skin areas 3 by 3 cm were tattooed on the left midside of 24 lambs at 1 month of age. The wool produced on these areas, and the areas of the tattoos, were measured at 4-monthly intervals from 4 months of age until 28 months. The amount of wool produced m7as proportional to the area in each of the six periods. There was also a highly significant difference between periods and between sheep in the amount of wool produced after adjustment for differences in tattoo area.

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