The value of production from a clipped measured area as an index of fleece weight.

1955 ◽  
Vol 6 (1) ◽  
pp. 91 ◽  
Author(s):  
FHW Morley ◽  
LW Lockart ◽  
EC Davis

The correlation between greasy wool production per unit area, obtained by clipping and measuring an area of about 100 cm² on the midside, and greasy fleece weight at shearing was about 0.58. Wool production from such an area over periods of 7½ or 3½ months was almost as useful as production for 11 months for predicting greasy fleece weight. The multiple correlation coefficient between greasy fleece weight as the dependant variable and production per unit area and 11-months' body weight was 0.79 in 66 rams and 0.71 in 82 ewes. The inclusion of fold score did not improve prediction appreciably. The equation W = P/110 + B1 /12 may be used to predict greasy fleece weight (lb), W, where P is production over 11 months of greasy wool (mg/cm²) and B1 is 11-months' body weight (Ib). A table of this function is included so that values may be read directly. The technique may be a useful aid to selection of Merino sheep if recording of actual fleece weights is difficult or impossible. Nevertheless it should not be regarded as more than a moderately accurate substitute for actual fleece-weighing.

1967 ◽  
Vol 20 (1) ◽  
pp. 153 ◽  
Author(s):  
PJ Reis ◽  
DA Tunks ◽  
OB Williams ◽  
AJ Williams

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.


1956 ◽  
Vol 7 (1) ◽  
pp. 57 ◽  
Author(s):  
PG Schinckel

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.


1989 ◽  
Vol 40 (2) ◽  
pp. 433 ◽  
Author(s):  
SI Mortimer ◽  
KD Atkins

Wool production traits were measured on Merino hogget ewes in an unselected multiple-bloodline flock over a 7-year period at Trangie Agricultural Research Centre, N.S.W. The traits measured were greasy fleece weight (GFW), skirted fleece weight (SKFW), yield (Y), clean fleece weight (CFW), fibre diameter (FD), body weight (BWT) and staple length (SL). These measurements were used to examine genetic differences between and within flocks of Merino sheep, and to estimate heritability of and genetic and phenotypic correlations among these traits. Significant strain, flock within strain and flock effects were present for all traits. Interactions between these effects and year were non-significant. Within-flock genetic variance was always larger than between-flock within strain genetic variance for each trait. The influence of environmental effects on these traits was also examined. The environmental effects of birth-rearing type, age at observation and age of dam together accounted for about 7-10% of the total within-flock variation in fleece weights and body weight.After adjusting for significant environmental effects, paternal half-sib heritability estimates were 0.29 �. 0.06 for GFW, 0.22 � 0.05 for SKFW, 0.35 � 0.05 for Y, 0.30 �0.06 for CFW, 0.48 �0.07 for FD, 0.34 �. 0.06 for BWT and 0.44 �0.07 for SL. Estimates for genetic and phenotypic correlations were in agreement with published estimates except for the genetic correlation between CFW and FD (0.40 �. 0.11), and the genetic correlations involving BWT, which were essentially zero. The implications of the results of this study for the genetic improvement of Merino sheep for wool production are discussed.


1969 ◽  
Vol 20 (6) ◽  
pp. 1177 ◽  
Author(s):  
T Nay ◽  
RH Hayman

Phenotypic correlations between body weight, follicle characters, and fleece characters have been investigated in a flock of 95 fine-wool non-Peppin Merino wethers, reared in the same locality under the same conditions. The results indicated that three follicle characters, follicle chord, follicle depth, and the index of follicle bending, were independent of body weight. It was found, in agreement with the results of other workers, that body weight was highly correlated with both greasy and clean wool weights (r = 0.53 and 0.51 respectively). It was also found that follicle characters were significantly correlated with most of the fleece characters which contribute to the clean fleece weight per unit area of skin. The correlation coefficient of wool weight per unit area of skin with follicle chord was 0.33, with follicle depth 0.28, and with follicle bending index –0.35. The follicle characters were also correlated with greasy and clean fleece weights. Crimp number per inch was predicted for individual animals by using as criterion the length of the follicle chord. A highly significant correlation coefficient of 0.67 was obtained between predicted and observed crimp number. The close relationship between crimp chord and follicle chord reported in previous work was confirmed. It is suggested that simultaneous selection for body weight and certain follicle characters may have an additive effect on the production of clean wool. It is also suggested that the genetic antagonism between clean wool weight and number of crimps per inch can be explained in anatomical terms.


1963 ◽  
Vol 3 (11) ◽  
pp. 262 ◽  
Author(s):  
RB Dun

Two drops of lambs were produced in spring 1959 and 1961 by mating poll rams (Pp) to knobbed ewes (pp). At marking time (1-4 wk), a random half of ram lambs of the Pp group and of the pp group were castrated. The rams and wethers were grown together and the following measurements were made-greasy fleece weight, clean scoured yield, clean fleece weight, staple length, crimps per inch, fold score, body weights at weaning and 17 months, and mortality to 17 months. The analyses showed no evidence of significant poll-genotype x sex interactions caused by superiority of Pp rams and pp wethers. It was concluded that segregation of the poll gene had no influence on any of the production characters studied. Rams cut six per cent more clean wool than wethers, but due to the large difference in size, clean wool production per lb body weight favoured wethers by 19 per cent. The ram's wool showed six per cent finer crimping than the wethers' fleece.


1983 ◽  
Vol 37 (3) ◽  
pp. 449-454
Author(s):  
R. Gonzàlez ◽  
A. Lombardini ◽  
W. Ibañez

ABSTRACTMedium-wool Australian Merino rams were sampled in 1978 and 1979 to estimate the relationships between the follicle curvature score, fleece and body characteristics.As a high correlation coefficient between two independent observers was found in both years, only one observer was used to correlate follicle curvature score with wool production.Repeatability of the follicle score between lambs at weaning and 14- to 15-month-old rams was 0·61*** and 0·65***.Clean fleece weight was significantly correlated with greasy fleece weight (0·8***, 0·9***), clean scoured yield (0·6***, 0·7***), staple length (0·4*, 0·5**) and crimps per cm (-0·3, -0·4*), but the correlation was very low with fibre diameter (0·01, 0·06).The correlation of clean fleece weight with body weight at 14 to 15 months varied between 0·2 and 0·5 (P < 0·001).Follicle curvature score was significantly correlated with clean fleece weight (-0·5**), clean scoured yield (0·6***, 0·7***), staple length (-0·4*, -0·7***), fibre diameter (0·3, 0·6***) and crimps per cm (0·4*. 0·6***). Non-significant correlations of follicle curvature score with greasy fleece weight (–0·2) and body weight at 14 to 15 months (–0·04, –0·1) were found.Depending on whether the proportion of superior 14- to 15-month-old rams which are to be retained for breeding is 0·10 or 0·05, then, according to our data, the proportion of lambs that can be culled at weaning (with an accuracy of P < 0·05) is 0·31 or 0·42, respectively.


2018 ◽  
Vol 1 (01) ◽  
pp. 17
Author(s):  
Ramlan Ruvendi

The study was carried out to find out whether there were influence and correlation bet-ween : a) Reward received by the IRDABI’s employees on their job satisfaction. b) style of the leader-ship on the job satisfaction. c) Reward together with style of leadership on the job satisfaction of IR-DABI’s employees.The result of the study showed that there was significant correlation and influence between the reward on the job satisfaction with was shown by the value of partial correlation coefficient of 0.6185 and coefficient of multiple regression for reward variable (β1) of 0.412. The influence of variable for style of leadership on the job satisfaction was also significant with the partial correlation coefficient of 0.5495 and coefficient of multiple regression (β2) of 0.355.In the test of Analysis of Variance (ANOVA) on the equation of multiple regression show that F-value was bigger that F-table (F = 58.97 > F-table = 3.098) or the Probability Value smaller than 0.05. At showed that there was significant correlation and influence between reward variables all together with style of leadership on the job satisfaction of employees. The value of multiple correlation coefficient (R) was 0.751 and R Square (R2) was 0.564. Value of R Square (0.564) meant that 56.5% of variation pro-portion total of job satisfaction can be eliminated of equation of multiple regression was used as the es-timator rather than using average value of job satisfaction as the estimator.


Author(s):  
А. I. Grabovets ◽  
V. P. Kadushkina ◽  
S. А. Kovalenko

With the growing aridity of the climate on the Don, it became necessary to improve the methodology for conducting the  breeding of spring durum wheat. The main method of obtaining the source material remains intraspecific step hybridization. Crossings were performed between genetically distant forms, differing in origin and required traits and properties. The use of chemical mutagenesis was a productive way to change the heredity of genotypes in terms of drought tolerance. When breeding for productivity, both in dry years of research and in favorable years, the most objective markers were identified — the size of the aerial mass, the mass of grain per plant, spike, and harvest index. The magnitude of the correlation coefficients between the yield per unit area and the elements of its structure is established. It was most closely associated with them in dry years, while in wet years it decreased. Power the correlation of the characteristics of the pair - the grain yield per square meter - the aboveground biomass averaged r = 0.73, and in dry years it was higher (0.91) than in favorable ones (0.61 - 0.70) , between the harvest and the harvest index - r = 0.81 (on average). In dry years, the correlation coefficient increased to 0.92. Research data confirms the greatest importance of the mass of grain from one ear and the plant in the formation of grain yield per unit area in both dry and wet years. In dry years, the correlation coefficient between yield and grain mass per plant was on average r = 0.80; in favorable years, r = 0.69. The relationship between yield and grain mass from the ear was greater — r = 0.84 and r = 0.82, respectively. Consequently, the breeding significance of the aboveground mass and the productivity of the ear, as a criterion for the selection of the crop, especially increases in the dry years. They were basic in the selection.


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