Vital statistics for an experimental flock of Merino sheep. III. Factors affecting wool and body characteristics, including the effect of age of ewe and its possible interaction with method of selection

1966 ◽  
Vol 17 (4) ◽  
pp. 557 ◽  
Author(s):  
GH Brown ◽  
HN Turner ◽  
SSY Young ◽  
CHS Dolling
Keyword(s):  
Body Weight ◽  
Fibre Diameter ◽  
Vital Statistics ◽  
Fibre Volume ◽  
Age Changes ◽  
Factors Affecting ◽  
Fibre Number ◽  
The Mean ◽  
Selection For ◽  
Staple Length

Estimates were made of the effects of the following factors on 10 fleece and body characteristics measured on breeding ewes aged 1½ to 10½ years in three mating groups over a period of 15 years: age of ewe, single or twin birth, age of dam, the ewe's own lambing performance, the year in which measurements were made, and the year in which each set of ewes was born. Two groups (S and MS) were under selection for high clean wool weight at 15–16 months, with a ceiling on wrinkle score and fibre diameter, while the third (C) was a random control. Changes with age were present in all characteristics and were similar in the three groups. The finding that selection on wool weight at an early age had no effect on subsequent age changes in any characteristic is of considerable importance. Greasy and clean wool weight reached a maximum at 34 years, then declined by 0.3–0.2 1b per year. Percentage clean yield, fibre diameter, body weight, and wrinkle score had maxima at 5½ to 6½ years. Staple length fell consistently by approximately 0.2 cm per year, while face cover rose consistently but slightly. Crimp number rose, fell, and rose again, while fibre number rose, fell, and remained constant from 4½ years. The chief source of increase in wool weight from l½ to 3½ years was an increase in the total number of fibres. The chief source of the subsequent fall was a decrease in fibre volume, with a minor contribution from a fall in total fibre number after 6½ years. Twin-born ewes cut 0.21 lb (4.2% of the mean) less clean wool per year over their lifetime than single-born ewes, while the progeny of 2-year-old ewes cut 0.32 lb (6.4%) less than the progeny of adults. The main source of lower weight in each case was a lower total fibre number. Pregnancy lowered clean wool weight more than lactation, the separate effects being 0.87 and 0.38 lb respectively (17.4 and 7.7% of the mean) and the combined effect 1.25 1b or 25.1%. Pregnancy lowered total fibre number but lactation had no further effect. Mean clean wool weights over all ages in the C group varied from year to year, the range being from 1.08 lb (21.6%)below the mean to 0.97 lb (19.4%) above. Differences in total fibre number contributed between one-third and two-thirds of the variation. Ewes born in consecutive years in the S and MS groups showed marked upward trends in clean wool weight, fibre number, and staple length, with a marked downward trend in crimp number and a slight upward trend in body weight. These trends demonstrate direct and correlated responses to the strong selection for high clean wool weight at 15–16 months of age, and the associated slight selection against fibre diameter and wrinkle score. The mean annual increases in clean wool weight were 0.15 and 0.11 Ib (3.0 and 2.2%) in the S and MS groups, approximately 40% of the increase arising from increased total fibre number and 40% from increased staple length. The effects of age and lambing performance can be used to predict productivity in flocks of differing age structures. As the casting age rises to 54 years changes in productivity are negligible. With a rise in casting age to 7½ years the average clean wool weight of the flock would fall by 0.14 lb, with a slight decrease in staple length and crimp number. These changes need to be balanced against any increased lambing percentage or decreased annual genetic gain due to increased generation interval. Comparison with other available figures indicates that age changes may vary from one area to another.

Response to selection in Australian Merino sheep. III. Single character selection for high and low values of wool weight and its components

1970 ◽  
Vol 21 (6) ◽  
pp. 955 ◽  
Author(s):  
HN Turner ◽  
MG Brooker ◽  
CHS Dolling
Keyword(s):  
Body Weight ◽  
Unit Area ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Initial Response ◽  
Skin Area ◽  
Correlated Responses ◽  
Fibre Number ◽  
Selection For ◽  
Staple Length

Direct and correlated responses are reported for 10 traits in eight pairs of lines under selection for high and low values of single characteristics : clean wool weight per head, clean wool weight per unit skin area (measured only in the groups under selection for it), body weight, wrinkle score, fibre number per unit skin area (adjusted for body weight), fibre diameter, staple length, and percentage clean yield. All groups showed overall divergence in the character under selection, though response was not always symmetrical, and in two cases (long staple and low fibre number) there was no continuing response after the initial response to extreme selection of the base parents. In all except one case, whenever previous estimates of genetic correlation were at the level of 0.2 or higher, correlated responses were in the predicted direction, though not always symmetrical in magnitude. The exception was a previously reported negative correlation between fibre number and staple length, which was not exhibited under selection for either character. Where two characters of a pair were under selection, reciprocal responses agreed in sign; magnitude will be examined in a later paper. Wool per unit area was shown to have a greater influence on clean wool weight than that of surface area, with staple length on this occasion being the most important component of wool per unit area. Reasons for an apparent decrease in the relative importance of fibre number are discussed. Three other points of importance in sheep breeding are again emphasized by these results : 1. Crimp in several pairs of groups was a poor indicator of fibre diameter. 2. Increases in clean wool weight were associated with falls in crimp number, even though fibre diameter actually became finer; diameter, not crimp, should therefore be used as a guide to wool quality. 3. The absence of genetic correlations DL and NL indicates that selection can be for high N (fibre number) with high L (staple length) and low D (fibre diameter) -in other words, a desirable fleece -with no impeding genetic correlations.

Effects of divergent selection for body weight on fibre number and diameter in two mouse muscles

1973 ◽  
Vol 16 (1) ◽  
pp. 7-16 ◽  
Author(s):  
J. P. Hanrahan ◽  
A. C. Hooper ◽  
J. C. McCarthy
Keyword(s):  
Body Weight ◽  
Fibre Diameter ◽  
Correlated Response ◽  
Weight Changes ◽  
Body Weight Changes ◽  
Muscle Weight ◽  
Phenotypic Correlations ◽  
Fibre Number ◽  
Selection For ◽  
Anterior Tibialis

SUMMARYThe effects of selection for increased or decreased body weight in mice, at 5 or 10 weeks of age, on the fibre number, fibre diameter and weight of the m. sternomastoideus and m. anterior tibialis muscles were studied. Unselected control mice were also included. Significant effects were detected in the case of each of the traits. However, the magnitude of any particular correlated response to selection varied between muscles and between selection ages in an unsystematic fashion. Most of the changes in muscle weight resulting from selection were attributable to positively correlated changes in fibre number but they were also accompanied by changes in fibre diameter in some cases.The correlated responses described indicate the difficulty of predicting how selection for body weight changes will influence cellular structure of any given muscle.Phenotypic correlations between muscle fibre number and diameter were essentially zero. The phenotypic correlations between muscle weight and fibre number and fibre diameter were positive.Sex had no effect on fibre number but had an effect on fibre diameter which depended on the particular muscle and the age of the animal.

Hornedness and polledness in sheep. 5. Some effects of the horn alleles on characters in the Merino

1961 ◽  
Vol 12 (3) ◽  
pp. 483
Author(s):  
CHS Dolling ◽  
NB Carter
Keyword(s):  
Body Weight ◽  
Fibre Diameter ◽  
The Third ◽  
Horn Growth ◽  
Significant Difference ◽  
Fibre Number ◽  
Staple Length

The influence on certain characters of the three alleles which affect horn growth has been investigated in three flocks of medium Peppin Merinos. These alleles have been named P, P', and p. The characters investigated were: greasy and clean wool weight per head, body weight, wrinkle score, fibre number per sq. millimetre of' skin, fibre diameter, staple length, clean scoured yield, crimps per inch, face cover, and, on some sheep, spinning count, character, colour, and handle. Comparisons between Pp and pp rams and ewes revealed that Pp rams had a significantly lower fibre number and a higher fibre diameter than their pp halfb-rothers, but there was no other evidence of any relationship between horn genotype and the phenotype of the above characters in either sex. In comparisons between Pp and P'p sheep, rams showed no significant differences, although they had the same hornedness phenotypes as Pp and pp rams. Pp ewes cut more clean wool and greasy wool than P'p ewes at 12 months of age, but not at 22 or 30 months. Pp ewes also had a higher fibre number at 12 months and a lower fibre diameter at 22 months than P'p ewes. In the third flock, comparison \\-as made between P'P' plus P'p ewes, which have female horns, and pp ewes, which have either scurs or knobs. In none of the above characters was there any significant difference between ewes with and without, horns. The presence of P had no demonstrable effect on spinning count, character, colonr, or handle in either the Pp v. pp or the Pp v. P'p comparison. Sire x hornedness genotype interactions were found in the Pp v. P'p comparisons of body weight at 22 months for rams and spinning count for ewes.

Effects of selection for body size on the weight and cellular structure of seven mouse muscles

1973 ◽  
Vol 17 (2) ◽  
pp. 187-196 ◽  
Author(s):  
Ignatius Byrne ◽  
J. C. Hooper ◽  
J. C. Mccarthy
Keyword(s):  
Body Weight ◽  
Body Size ◽  
Tibialis Anterior ◽  
Biceps Brachii ◽  
Fibre Diameter ◽  
Rectus Femoris ◽  
Muscle Weight ◽  
Fibre Number ◽  
Selection For ◽  
Psoas Major

SUMMARYThe effects of selection for increased and decreased body weight in mice at 5 and at 10 weeks of age on the weight and mean fibre diameter and number of seven different muscles were studied by dissecting and histologically examining animals from large, small and unselected control lines. The purpose was to learn how selection for body size affects muscle weight and its components. Selection for increased body weight significantly increased the weight of m. biceps brachii, m. tibialis anterior, m. pectoralis major, m. brachio-radialis, m. soleus, m. rectus femoris and m. psoas major. These increases in muscle weight reflected increases in both fibre diameter and number although there were a few exceptions. Selection for low body weight produced decreases in the weight of all muscles. These reflected significant reductions in mean fibre diameter and, in most cases, fibre number. Significant estimates of heterosis in mean fibre diameter were obtained in m. biceps brachii and m. tibialis anterior from crosses between the Large and Small lines selected at 5 weeks and also between the lines selected at 10 weeks of age, respectively.

Vital statistics for an experimental flock of Merino sheep. V. The effects pf age of ram, maternal handicap, and year of measurement on 10 wool and body characteristics for unselected rams

1968 ◽  
Vol 19 (5) ◽  
pp. 825 ◽  
Author(s):  
GH Brown ◽  
HN Turner ◽  
CHS Dollling
Keyword(s):  
Body Weight ◽  
Population Density ◽  
Similar Pattern ◽  
Fibre Diameter ◽  
Vital Statistics ◽  
Mean Difference ◽  
Body Area ◽  
Merino Sheep ◽  
Twin Birth ◽  
Staple Length

Estimates were made of the effects of the following factors on 10 fleece and body characteristics measured on rams aged 1½ to 5½ years in a randomly bred control flock, for rams born 1953 to 1957 inclusive: age of ram, single or twin birth, age of dam, and the year in which measurements were made. Changes with age were present in all characteristics and the ranges of the age deviations from the overall mean were larger in magnitude than the corresponding figures for ewes. Greasy and clean wool weights showed a similar pattern of change with age as ewes. For greasy wool weight the age deviation increased from –2.4 lb at 1½ years to 1.1 lb at 3½ years and then declined to 0.5 lb at 5½ years of age. The corresponding figures for clean wool weight were –0.7 to 0.5 lb. falling to –0.2 lb at 5½ years of age. Other characteristics showed different patterns of change with age from the corresponding figures for ewes. Staple length, crimps per inch, yield, and fibre population density decreased with age over the range available, whilst face cover, body weight, fibre diameter, and wrinkle score increased. The fitted mean difference in clean wool weight between rams and ewes was 33%, largely attributed to differences in body area (25%) with a smaller contribution from staple length (7%). Twin-born rams cut 0.28 lb of clean wool weight per year less than single-born rams over the five shearings, whilst the progeny of 2-year-old dams did not differ significantly from the progeny of adults. Large between-year differences occurred for most characteristics. For clean wool weight the range was from –1.52 to 1.44 lb, fibre volunme being the most important component, while for body weight the range was –18.6 to 19.7 lb.

Relative economic importance of some wool quality traits for Merino and crossbred wool types

1970 ◽  
Vol 10 (46) ◽  
pp. 544 ◽  
Author(s):  
PD Mullaney ◽  
ID Sanderson
Keyword(s):  
Selection Index ◽  
Fibre Diameter ◽  
Economic Importance ◽  
Quality Traits ◽  
Regression Analyses ◽  
Independent Variables ◽  
Economic Weights ◽  
Australian Wool ◽  
The Mean ◽  
Selection For

The economic weights of various quality traits of both Merino and crossbred wool types hive been estimated. Australian averages of clean wool prices for Australian Wool Board wool types, into which mid-side samples of fleece were classified, have been used.For each of fifteen seasons, 1953-54 to 1967-68, the mean clean wool price for each wool type was expressed as a percentage of the mean wool price for all types in that season. Rank correlations for price-type means were high between seasons, varying between 0.91 and 0.98. Further analyses were therefore performed using prices averaged for the 15 seasons. Multiple regression analyses were carried out, the dependent variable being the mean price for each fleece type, expressed as a percentage of the average price of all types for al) seasons and the independent variables being the measurement of fibre diameter, crimps per inch and length, and the subjective gradings of colour, handle, character, and quality number. For both Merino and crossbred wool types, the major determinants of price were quality number, colour, and handle, with quality number being of overwhelming importance. The remaining variables were not important as joint determinants of price, and were deleted from the analyses. Quality number, colour, and handle controlled about 81 and 86 per cent of the variation in price for Merino and crossbred wool types. It is likely that most progress in selection for wool production would be made by incorporating these findings into a selection index.

Selection for fertility in Australian Merino sheep

1963 ◽  
Vol 14 (4) ◽  
pp. 460 ◽  
Author(s):  
SSY Young ◽  
HN Turner ◽  
CHS Dolling
Keyword(s):  
Body Weight ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Likelihood Method ◽  
Mass Selection ◽  
Genetic Progress ◽  
Subsequent Performance ◽  
Fertility Trait ◽  
Selection For ◽  
The Difference

Phenotypic and genetic parameters for fertility in sheep, in terms of number of lambs born and number weaned, have been estimated in a flock of medium Peppin Merinos. Repeatability of fertility traits over all ages is low, but there is an age effect, the record at 3 years of age having a higher value than those at 2 or 4 years. The regression of subsequent performance on a difference of 1 lamb at the initial lambing was higher for the difference between 1 and 2 lambs than between 0 and 1 lamb, which indicated that selection for twins is likely to raise fertility in the current flock more rapidly than selection against barrenness. The estimate of heritability for 2 years of age was negligible for each fertility trait, but the estimates for the 3-year-old record were higher, the value for lambs born being over 0.3. Mass selection for number of lambs born at 3 years of age would thus be expected to lead to appreciable genetic progress, while there would be at least some progress in number of lambs weaned. Phenotypic and genetic correlations were also estimated between fertility at different ages and 10 sheep and wool traits measured at 15–16 months of age. Phenotypically, fertility is positively correlated with body weight and negatively with skin wrinkle score. Genetically, it is suggested from the estimates that fertility is positively correlated with body weight and staple length and negatively correlated with fibre diameter, clean scoured yield, and wrinkle score. No phenotypic or genetic correlation was found between greasy or clean wool weight and either measure of fertility. The application of the findings to breeding for higher fertility is discussed. In an appendix, a maximum likelihood method of estimating heritability for all-or-none traits in half-sib data is presented.

scholarly journals Genetic parameters for wool traits in Finnsheep lambs

2008 ◽  
Vol 16 (2) ◽  
pp. 124 ◽  
Author(s):  
M-L. PUNTILA ◽  
K. MÄKI ◽  
A. NYLANDER
Keyword(s):  
Genetic Correlation ◽  
Variance Components ◽  
Genetic Parameters ◽  
Fibre Diameter ◽  
Live Weight ◽  
Bivariate Analysis ◽  
Component Estimation ◽  
Selection For ◽  
Fleece Weight ◽  
Staple Length

Genetic parameters were estimated for wool characteristics of white and coloured Finnsheep. The data consisted of 5 309 lambs from ordinary production flocks, the Finnsheep nucleus flock and a breeding flock. The variance component estimation was done applying REML analyses. Wool traits included fleece uniformity, density, staple formation, lustre, crimp frequency, fineness grade and staple length. There was a smaller dataset that contained also lamb live weight, greasy fleece weight and additional fleece characteristics including fibre diameter measured with the OFDA method. The variance components for direct and maternal effects were estimated using bivariate analysis for 42-day, 120-day weight and greasy fleece weight. Heritability for visually assessed wool characteristics varied from 0.23 to 0.43 and for measured traits from 0.45 to 0.62. Staple length had a high negative genetic correlation with crimp frequency and fineness grade. Heritability of greasy fleece weight was high (0.55) and that of fibre diameter 0.62. The genetic correlation between crimp frequency and fibre diameter was negative (- 0.56). The results imply that the assessed traits are useful indicators for fleece quality and those of major importance can be introduced into the breeding programme. The results suggest that there is no antagonism in selection for both growth capacity and wool quantity.;

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.

Fleece characters and their influence on wool production per unit area of skin in Merino sheep

1958 ◽  
Vol 9 (3) ◽  
pp. 363 ◽  
Author(s):  
SSY Young ◽  
RE Chapman
Keyword(s):  
Unit Area ◽  
Fibre Diameter ◽  
Fibre Volume ◽  
Cross Sectional Area ◽  
The Body ◽  
Sectional Area ◽  
Cross Sectional ◽  
Fibre Density ◽  
Wool Production ◽  
Staple Length

The variations in fleece characters and the dependence of wool production per unit area of skin on these characters were studied with 15 sheep in both a medium and a strong-wool strain of Merino. Small but significant differences in staple length and fibre diameter were found between regions on the body, whereas differences in density were large. The variation in density was about three times as large as those in staple length and fibre diameter. Distinct dorsoventral and anteroposterior gradients over the body existed for fibre density, but not for staple length and fibre diameter. The influences of the fleece characters on wool production per unit area were somewhat different in the two strains, and changed with level of production. Among the medium-wool sheep, fibre density had the largest effect on production, with staple length less and mean fibre cross-sectional area least. Among the strong-wool sheep, length was more important than density, which in turn was more important than fibre cross-sectional area. The combined data indicated that as mean wool weight per unit area increased, the influence of density rose to a maximum and then diminished, whereupon mean fibre volume became the main contributor to wool weight. For different positions on the body of individual sheep, the dependence of wool production per unit area on the fleece characters was found to be similar in the two strains. Fibre density had the major effect in determining the level of production, whereas the influences of staple length and fibre area were negligible.

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