THE ACCUMULATIVE EFFECT OF FINNSHEEP BREEDING IN CROSSBREEDING SCHEMES: WOOL PRODUCTION AND FLEECE CHARACTERISTICS

1987 ◽  
Vol 67 (1) ◽  
pp. 1-11 ◽  
Author(s):  
MOHAMED H. FAHMY

Wool fibers grown on 2 cm2 of skin were removed from the shoulder region of 273 female yearlings born at La Pocatiere Experimental Farm over a period of 3 yr. The yearlings represented nine genetic groups, Finnsheep, DLS (a population of 1/2 Dorset, 1/4 Leicester, 1/4 Suffolk) and seven combinations ranging from 1/8 to 7/8 Finnsheep breeding. The traits studied were staple length, fiber density, clean wool percentage, fiber length and thickness and their variability. Grease fleece weight (GFW) was recorded at first shearing on the 273 yearlings and on an additional 90 female yearlings. GFW was subsequently recorded at yearly intervals up to the 5th shearing. GFW of Finnsheep (F) was 2.3 kg for yearlings and averaged 2.0 kg for older ewes compared to 2.3 and 2.8 kg for the DLS, respectively. The crosses showed positive deviations from the expected means of their parental breeds, the highest was expressed in the [Formula: see text] and 5/8F crosses, GFW exceeded in many crosses that of the better parental breed. The relationship between GFW and the proportion of Finnsheep in the genetic group was linear in second shearing and curvilinear for later shearings. Significant linear relations were also observed in fiber thickness and variability in both fiber length and fiber thickness, whereas significant curvilinear relations were observed in clean wool percentage and fiber length. Compared to DLS, Finnsheep had a higher fiber density (1950 vs. 1551 cm−2), fibers were longer (19.1 vs. 15.8 cm) more variable in length (SD = 4.66 vs. 2.96 cm), finer (20.5 vs. 25.5 μm, and uniform in fiber thickness (SD = 4.8 vs. 5.9 μm), these differences being statistically significant. Most of the crosses exhibited positive heterosis particularly in clean wool percentage, staple and fiber length. The highest heterosis was often manifested in the [Formula: see text] cross. Key words: Wool production, fleece characteristics, crossbreeding, heterosis, Finnsheep, DLS sheep

1988 ◽  
Vol 60 (6) ◽  
pp. 481-491
Author(s):  
M. H. Fahmy

Finnsheep (F) was used in a crossbreeding project to improve overall productivity of the DLS breed. Productive and reproductive traits of seven crossbred combinations ranging from 1/8F to 7/8F breeding were compared to those of the two parental breeds. Suffolk rams were used to mate all ewes (361) for five parturitions (1312 records). Ovulation rate (OR) and litter size (LS) at birth for all the groups increased progressively as F breeding increased. The 4/8F ewes weaned the heaviest litters. Percentage of ova lost per ewe mated ranged from 18 % to 29 %. Preweaning mortality rate was highest in F ewes. Total kg of lambs weaned per ewe exposed was highest in 4/8F followed by F whereas that of DLS was lowest. The 4/8F exhibited 25 % heterosis (H) in kg of lambs weaned per ewe exposed. The linear regressions of OR (b = .24), of LS at birth (b = .14) and at weaning (b = .08) on proportion of F breeding in crosses were significant. The regressions were quadratic for percent ova lost and lamb mortality at weaning. The crosses showed positive H in grease fleece weight (GFW), the highest being expressed by the 4/8F and 5/8F crosses. Significant linear relationships were observed between F breeding and GFW (2nd shearing), fiber thickness and variability in both fiber length and fiber thickness, whereas the relationships of F breeding with GFW (3rd and later shearings), clean wool percentage and fiber length were quadratic. Most of the crosses exhibited positive H particularly in clean wool percentage and in staple and fiber length. H was often highest in the 4/8F cross. Genetic group of dam had a significant effect on age at slaughter, leg, loin and kidney fat as a percent of the carcass, lean, fat and bone percent of the 12th rib and fat thickness over loin-eye muscle. A significant linear relationship existed between most of these carcass measurements and the proportion of F breeding in the lambs’ dam.


1958 ◽  
Vol 38 (1) ◽  
pp. 53-60
Author(s):  
S. B. Slen ◽  
E. C. Banky ◽  
H. F. Peters

The relationship of shearling and second-year clean fleece weight to total wool production, i.e., first 5 years of life, was analysed in three breeds of range sheep (Canadian Corriedale, Rambouillet, and Romnelet) to determine its usefulness in selection for increased wool production.A correlation of +.67 (p <.01) between shearling clean fleece weight and the sum of the four mature fleece weights was obtained in the three breeds studied. When the first mature weight (second fleece) was correlated with the total weight of the three subsequent fleeces, the correlation was increased significantly (p <.01). Consequently, the second fleece appeared to be a more reliable estimate of lifetime production than shearling weight. No breed differences in these correlations were found when lifetime production was compared to shearling or to second-year fleece weights. The regression coefficients of lifetime production on shearling fleece weight showed that a shearling ewe which produced 1.0 lb. of clean wool above the average produced approximately 3.0 lb. more than the average during her productive life.Shearling fleece weight was found to represent 83, 77, and 80 per cent of the maximum mature fleece weight in the Canadian Corriedale, Rambouillet, and Romnelet, respectively. No breed differences were observed in this relationship.The repeatability of annual clean fleece weight was found to be.93,.83, and.76 for the Rambouillet, Romnelet, and Canadian Corriedale, respectively.


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.


Author(s):  
Osman Mahgoub ◽  
Isam T. Kadim ◽  
Ahmed Al-Dhahab ◽  
Reynaldo B. Bello ◽  
Issa S. Al-Amri ◽  
...  

Wool production and quality measurements were carried out on 100 Omani native female sheep (body weight 38.6 ± 5.5 kg; age 993 ± 488 d). Sheep were kept in partially shaded pens and fed ad libitum Rhodes grass hay (crude protein 8.83%) plus a daily amount of 200 g general ruminant concentrate (crude protein 16.5% DM). Animals were shorn once a year and samples were taken from the left mid-side site to determine fleece and fiber characteristics. The scanning electron microscope (SEM) was used to study the fine appearance of the wool fibers. A skin sample was used to study the histological arrangement and number of secondary and primary follicles. The greasy fleece weight (GFW) in Omani sheep ranged between 0.50- 2.65 kg (mean 1.12 ± 0.43 kg) and the GFW expressed as a percentage of BW ranged between 1.0-7.6 with a mean of 2.9 ± 1.16. Clean wool yield in Omani sheep fleece ranged between 57.1 and 88.4% with a mean of 76.4 ± 7.6. Omani sheep fleece contained various staple shapes and had a mean staple length of 22.9 ± 1.16 cm, 4.3 ± 0.8 crimps per staple; and a mean fiber diameter of 46 ± 12 µm. Electron microscopy revealed three types of fibers; wrap-around, angled type and polygonal and elongated scales. This study indicated a wide variation in the wool characteristics of Omani native sheep fleece, which suggested that selection may be employed to improve wool production and quality in these sheep. 


1974 ◽  
Vol 14 (69) ◽  
pp. 441 ◽  
Author(s):  
GE Robards ◽  
AJ Williams ◽  
MHR Hunt

Two experiments were conducted in which the efficiency of wool production of Merino sheep selected for increased (Crimps Plus) and decreased (Crimps Minus) crimp frequency, and a randomly selected control flock, was examined under pen feeding conditions. Ewes for the second experiment were chosen from the same genetic flocks as those used in the first experiment, after a further 1.8 generations (six years) of selection. In the first experiment, in which four levels of roughage diet were offered to ewes from each of the genetic groups, Crimps Minus ewes consistently produced more wool and with a greater efficiency than Random ewes, which were superior in these two characters relative to Crimps Plus ewes. Similar results were obtained in the second experiment, in which ewes were fed to maintain liveweight. Wool production and efficiency of Fleece Plus ewes were greater than those of Crimps Minus ewes indicating a higher genetic correlation between efficiency and fleece weight than between efficiency and crimp frequency.


2021 ◽  
pp. 1-8
Author(s):  
Mustafa Avcu ◽  
Mehmet Metin ◽  
Raşit Kılıç ◽  
Muhammed Alpaslan

Background: In this study, optic coherence tomography (OCT) examination was performed to check whether there was any interaction between ophthalmic axonal structures in unilateral tinnitus patients, and the relationship between optic nerve thickness and cochlear nerve thickness was evaluated. Objective: The aim of the study was to evaluate the relatioship between hearing loss, tinnitus, and nerve thicknesses. Study Design: Prospective study. Setting: Tertiary referral university hospital. Patients: The study included 88 patients with unilateral tinnitus, for which no organic cause could be found in physical examination, psychiatric evaluation, or with imaging methods. Study groups were formed of the tinnitus side and control groups were formed of the healthy side as follows: Group 1 (Non-tinnitus side normal hearing values – n = 30), Group 2 (non-tinnitus side minimal hearing loss – n = 27), Group 3 (non-tinnitus side moderate hearing loss – n = 31), Group 4 (tinnitus side normal hearing values – n = 25), Group 5 (tinnitus side minimal hearing loss – n = 25), and Group 6 (tinnitus side moderate hearing loss – n = 38). Intervention: Retinal nerve fiber layer (RNFL) thickness was evaluated with OCT, and the cochlear nerve cross-sectional area was evaluated with MRI. Main Outcome Measures: RNFL measurements were taken with OCT from the subfoveal area (RNFL-SF) and 1.5 mm temporal to the fovea (RNFL-T µm) and nasal (RNFL-N µm) sectors. On MRI, 3 measurements were taken along the nerve from the cerebellopontine angle as far as the internal auditory canal, and the mean value of these 3 measurements was calculated. Results: When the groups were evaluated in respect of cochlear nerve thickness, a significant difference was seen between Group 1 and both the groups with hearing loss and the tinnitus groups. In the subgroup analysis, a statistically significant difference was determined between Group 1 and Groups 3, 4, 5, and 6 (p = 0.013, p = 0.003, p < 0.001, and p < 0.001, respectively). When the groups were evaluated in respect of the RNFL-SF (µm), RNFL-T (µm), and RNFL-N (µm) values, the differences were determined to be statistically significant (p < 0.001 for all). In the correlation analysis, a negative correlation was determined between hearing loss and cochlear nerve diameter (r: −0.184, p = 0.014), and RNFL-N (r: −0.272, p < 0.001) and between tinnitus and cochlear nerve diameter (r: −0.536, p < 0.001), and RNFL-T (r: −0.222, p < 0.009). Conclusion: The study results clearly showed a relationship between cochlear nerve fiber thickness and hearing loss and the severity of tinnitus in cases with unilateral tinnitus and that there could be neurodegenerative factors in the disease etiology. A similar relationship seen with the RNFL supports the study hypothesis.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jihun Choi ◽  
Hansol Lee ◽  
Bokyeong Sohn ◽  
Minjae Song ◽  
Sangmin Jeon

AbstractWe developed a 3D solar steam generator with the highest evaporation rate reported so far using a carbonized luffa sponge (CLS). The luffa sponge consisted of entangled fibers with a hierarchically porous structure; macropores between fibers, micro-sized pores in the fiber-thickness direction, and microchannels in the fiber-length direction. This structure remained after carbonization and played an important role in water transport. When the CLS was placed in the water, the microchannels in the fiber-length direction transported water to the top surface of the CLS by capillary action, and the micro-sized pores in the fiber-thickness direction delivered water to the entire fiber surface. The water evaporation rate under 1-sun illumination was 3.7 kg/m2/h, which increased to 14.5 kg/m2/h under 2 m/s wind that corresponded to the highest evaporation rate ever reported under the same condition. The high evaporation performance of the CLS was attributed to its hierarchically porous structure. In addition, it was found that the air temperature dropped by 3.6 °C when the wind passed through the CLS because of the absorption of the latent heat of vaporization. The heat absorbed by the CLS during water evaporation was calculated to be 9.7 kW/m2 under 1-sun illumination and 2 m/s wind, which was 10 times higher than the solar energy irradiated on the same area (1 kW/m2).


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.


1977 ◽  
Vol 47 (11) ◽  
pp. 755-760 ◽  
Author(s):  
Reba Lawson ◽  
Smith Worley ◽  
H. H. Ramey

A statistical evaluation was made of the relationship of certain fiber properties to cohesive force and coefficient of variation of cohesive force. Significant positive correlations were found between the cohesive force and fiber length, tenacity, and fiber yellowness (+b); negative correlations were found with fiber perimeter and reflectance (Rd). When length, colorimeter values, and Micronaire readings were used as independent variables in a stepwise regression program, 53% of the variation in the cohesive force could be explained by upper half mean length and Rd. The addition of other fiber properties whose measurement was influenced by fiber surface properties increased the explainable variation in the cohesive force to 71%.


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