Bioinformatics analysis of evolutionary characteristics and biochemical structure of FGF5 Gene in sheep.

Fibroblast growth factor (FGF) 5 regulates the development and periodicity of hair follicles, which can affect hair traits. Loss-of-function mutations associated with long-hair phenotypes have been described in several mammalian species. Sheep is an important economic animal, however, the evolution characterizations and biological mechanism of oFGF5 (Ovis aries FGF5) gene are still poorly understood. In this study, oFGF5 gene was obtained by resequencing the whole genome of three Dorper sheep and RACE of two Kazakh sheep FGF5. We proposed FGF5 was phylogenetically related to FGF4 family and oFGF5 clearly orthologed to goat FGF5. Six loci were found from the positive selection results of FGF5 and half of them located on signal peptide. The basically similar rates of function-altering substitutions in sheep and goat lineage and the rest of the mammalian lineage of 365 SNPs indicated that the FGF5 gene was quite conservative during evolution. Homology modeling of the oFGF5 suggested that it has a highly conserved FGF superfamily domain containing 10 ß-strands. Furthermore, the protein-protein docking analysis revealed that oFGF5 have the potential to form heterodimers with oFGFR1, the predicted interaction interface of FGF5-FGFR1 heterodimer was formed mainly by residues from FGF superfamily domain. Our observations suggested the evolutionary and structural biology features of oFGF5 might be relevant to its function about hair follicle development and modulating hair growth, and we confirmed our speculation by using the FGF5 gene editing sheep produced by CRISPR/Cas9 technology.

A 57-bp deletion in the ovine KAP6-1 gene affects wool fibre diameter.

High glycine-tyrosine keratin-associated proteins (HGT-KAPs) are predominantly present in the orthocortex of wool fibres. They vary in abundance in different wools and have been implicated in regulating wool fibre properties, but little is known about the functional roles of these proteins in the fibre matrix. In this study, we used polymerase chain reaction--single-strand conformational polymorphism (PCR-SSCP) analysis to screen for variation in a gene encoding the ovine HGT-KAP6-1 protein. We identified three gene variants (A, B and C). Variants A and B were similar to each other, with only three nucleotide differences occurring downstream of the coding sequence. However, variant C had a 57-bp deletion that would notionally result in a loss of 19 amino acids in the protein. The presence of C was found to be associated with an increase in mean fibre diameter (MFD), fibre diameter standard deviation (FDSD), coefficient of variation of fibre diameter (CVFD) and prickle factor (percentage of fibres over 30 microns; PF). Sheep of genotype BC produced wool of greater MFD, FDSD and PF than sheep of genotypes AA, AB and BB. The CVFD was greater in the BC sheep than the AB sheep. The results suggest that variation in ovine KRTAP6-1 affects wool fibre diameter-associated traits and that the 57-bp deletion in this gene would lead to coarser wool with greater FDSD, CVFD and PF.

Genome-wide association study for wool production traits in a Chinese Merino sheep population.

Genome-wide association studies (GWAS) provide a powerful approach for identifying quantitative trait loci without prior knowledge of location or function. To identify loci associated with wool production traits, we performed a genome-wide association study on a total of 765 Chinese Merino sheep (JunKen type) genotyped with 50 K single nucleotide polymorphisms (SNPs). In the present study, five wool production traits were examined: fiber diameter, fiber diameter coefficient of variation, fineness dispersion, staple length and crimp. We detected 28 genome-wide significant SNPs for fiber diameter, fiber diameter coefficient of variation, fineness dispersion, and crimp trait in the Chinese Merino sheep. About 43% of the significant SNP markers were located within known or predicted genes, including YWHAZ, KRTCAP3, TSPEAR, PIK3R4, KIF16B, PTPN3, GPRC5A, DDX47, TCF9, TPTE2, EPHA5 and NBEA genes. Our results not only confirm the results of previous reports, but also provide a suite of novel SNP markers and candidate genes associated with wool traits. Our findings will be useful for exploring the genetic control of wool traits in sheep.

Wool characteristics in the third generation of Arkharmerino × Ghezel and Arkharmerino × Moghani crossbreed sheep.

This investigation was conducted to evaluate the comparative productive performances and effect of some environmental factors on wool characteristics of Arkharmerino × Ghezel (Ar × Gh) and Arkharmerino × Moghani (Ar × Mo) crossbreed sheep. The mid-side fleece samples taken from animals during 2 years (2007-2008) were analyzed. Each sample was measured for average fiber diameter, fiber diameter variability, staple length, proportion of medullated fiber, proportion of kemp, and comfort factor. The comparative values for these fleece characteristics in F(3) generation Ar × Gh were 28.78 ± 0.48 µm, 36.84 ± 1.16%, 11.94 ± 0.35 cm, 7.07 ± 0.93%, 1.02 ± 0.23%, and 68.93%, respectively; while those traits were 29.79 ± 0.43 µm, 41.86 ± 1.16%, 11.96 ± 0.37 cm, 8.13 ± 1.06%, 2.71 ± 0.45%, and 63.33 ± 3.66% for Ar × Mo, respectively. The effects of genotype, sex, birth type, and year of birth were analyzed. Genotype had a significant (P < 0.01) effect on average fiber diameter and proportion of kemp, and Ar × Gh crossbreeds had lower diameter with less proportion of kemp. The two differences in fiber characteristics that were attributable to sex were fiber diameter variability and proportion of medullated fiber, and females had higher measure than males for both traits. Statistical analysis showed that crossbreeding with Arkharmerino generally had positive effects on the fleece favored to be used in the hand woven authentic carpet production.

Study of wool characteristics in the aranese ovine breed / Estudio de las características de la lana en la raza ovina aranesa

To date, no ethnological study on the wool characteristics of the Spanish Aranese ovine breed has been published. Fifty three animals belonging to this breed are tested as fleece samples. Each sample is analyzed for fleece type and length, yield by isoalcohol scouring, fiber length for each kind of fiber, variation in fiber diameter, and proportions of non-medullated and medullated or kemp fibers. Fiber length appears shorter than that previously reported for the breed by other authors. Fleeces of the Aranese sheep breed can be described as square, simple, "semi-open" and short with a relatively high yield by isoalcohol scouring and low medullation levels, thus indicating good potential quality and greater suitability for potential processing than other similar meat breeds.

Hasta el momento, ningún estudio etnológico sobre las características de la lana de la variedad española ovina Aranesa ha sido publicado. Cincuenta y tres animales de esta raza han sido analizados a partir de muestras de su vellón. Cada muestra se analizó para el tipo de vellón y longitud, su rendimiento mediante isoalcohol desgrasado, longitud de las fibras para cada tipo de fibra, variación en el diámetro de la fibra, y las proporciones de fibras no meduladas y meduladas o fibras kemp. La longitud de las fibras parece más corta que la reportada para esta raza por otros autores. El vellón de la raza ovina Aranesa se puede describir como cuadrado, simple, "semi-abierto" y corto, con un rendimiento relativamente alto por desengrasado mediante isoalcohol y bajos niveles de medulación, lo que indica la buena calidad potencial y mayor oportunidad para el procesamiento potencial que otras razas similares de carne.

Factors influencing the efficiency of a marker-assisted introgression programme in Merino sheep.

This study investigated a marker-assisted introgression programme in Australian Merino sheep. The goal was to introgress an allele with a large negative effect on fibre diameter into a Merino flock possessing medium average fibre diameter. The influence of two factors was explored: the strategy used to select animals from the purebred and backcross line for backcrossing purposes and the use of selection on background markers to accelerate the return to the purebred line's genome. The results were compared to introgression based on EBVs only. Introgression using EBVs only produced almost the same response in the dollar index as marker-based introgression methods. However, this study did not account for some of the costs associated with implementing the programmes, including the costs of phenotyping and genotyping. Given that the cost of measuring fibre diameter is low, it was concluded that introgression on EBVs only would be the preferred method since the marginal profit of marker-assisted introgression would not be large enough to cover the additional cost of genotyping. In marker-assisted introgression, reciprocal crossing of male and female selection candidates from the backcross and the purebred line was the most advantageous strategy from a practical and profit point of view. Selection for background markers was less profitable in this study than recovering the donor genome by selection on phenotype.

Genetic correlations among and between wool, growth and reproduction traits in Merino sheep.

Data from seven research resource flocks across Australia were combined to provide accurate estimates of genetic correlations among production traits in Merino sheep. The flocks represented contemporary Australian Merino fine, medium and broad wool strains over the past 30 years. Over 110,000 records were available for analysis for each of the major wool traits, and 50,000 records for reproduction and growth traits with over 2700 sires and 25,000 dams. Individual models developed from the single trait analyses were extended to the various combinations of two-trait models to obtain genetic correlations among six wool traits [clean fleece weight (CFW), greasy fleece weight, fibre diameter (FD), yield, coefficient of variation of fibre diameter and standard deviation of fibre diameter], four growth traits [birth weight, weaning weight, yearling weight (YWT), and hogget weight] and four reproduction traits [fertility, litter size, lambs born per ewe joined, lambs weaned per ewe joined (LW/EJ)]. This study has provided for the first time a comprehensive matrix of genetic correlations among these 14 wool, growth and reproduction traits. The large size of the data set has also provided estimates with very low standard errors. A moderate positive genetic correlation was observed between CFW and FD (0.29 +/- 0.02). YWT was positively correlated with CFW (0.23 +/- 0.04), FD (0.17 +/- 0.04) and LWEJ (0.58 +/- 0.06), while LW/EJ was negatively correlated with CFW (-0.26 +/- 0.05) and positively correlated with FD (0.06 +/- 0.04) and LS (0.68 +/- 0.04). These genetic correlations, together with the estimates of heritability and other parameters provide the basis for more accurate prediction of outcomes in complex sheep-breeding programmes designed to improve several traits.

A study on some physical attributes of Naeini sheep wool for textile industry.

In order to evaluate some physical and qualitative characteristics of Naeini sheep wool for using in textile industry, herds from 6 different regions of Isfahan province were chosen. Staple length from 3 different body parts (shoulder, side and britch) was measured prior to shearing. Wool samples were taken from a 100 cm2 surface on the mid-side of the Animals. Then the samples were transferred to the Laboratory of Animal Sciences for evaluations of some quality characteristics and to the Fiber Physics Laboratory for measuring tenacity, breaking strength and elongation at break of fibers. The means and standard deviations of staple length were estimated (10.8 +/- 2.36), (9.71 +/- 3.14) and (10.99 +/- 2.49) cm for shoulder, side and britch parts, respectively. The total average staple length of Naeini sheep (10.5 cm) is suitable for using in textile industry. Wool fibers of Naeini sheep have desirable tenacity and breaking strength (1.22 cN/dtex and 13.76 centi-Newton) to resist against mechanical tensions of the spinning step. However, Naeini sheep wool fibers have an adequate, but not a desirable % elongation at break (28.6%). Based on the fiber diameter mean of Naeini sheep and its variation (28.51 +/- 4.33 microm) the fleece grade of Naeini sheep was predicted 54's, which is an intermediate grade. However, by conducting breeding programs toward enhancing fleece grade, Naeini sheep wool will be simply applicable in textile industry.

Measurement of medullation in wool and mohair using an Optical Fibre Diameter Analyser.

We conducted three experiments to evaluate the Optical Fibre Diameter Analyser (OFDA) for estimating medullation (med [M], kemp [K], and total [T] medullated fiber content) in mohair and wool produced by Angora goats and sheep, respectively. Medullation can be a beneficial characteristic in certain types of wool, but it is highly undesirable in mohair and apparel wools. Current techniques for evaluating medullation in animal fibers are laborious, slow, and expensive. The OFDA had been modified by the manufacturer to measure fiber opacity distribution, a characteristic known to be indicative of medullation in white fibers, and was capable of providing such measurements in a very short time. Measurements made on magnified fiber images produced with a projection microscope (PM) were used as a reference for M, K, and T in fiber samples. An initial experiment with 124 mohair samples (T = .10 to 9.10%) seemed to indicate that OFDA estimates of M, K, and T were only poorly correlated with corresponding PM values (r2 = .5409, .1401, and .5576, respectively). However, a second experiment using wool and mohair samples containing a wider range of medullation (T = .58 to 26.54%) revealed that OFDA estimates of M, K, and T for wool were highly correlated with PM measurements (r2 = .9853, .9307, and .9728, respectively). Evidence was also obtained indicating that the low r2 values associated with mohair relationships were likely due to a combination of factors: 1) high variation among the standard PM measurements and 2) the relatively low M, K, and T contents of the mohair samples compared with wool. In a third experiment, greater accuracy was obtained in the PM measurements by evaluating many more individual fibers per sample (10,000). In this case, OFDA estimates of M, K, and T for mohair were highly correlated with corresponding PM measurements (r2 = .8601, .9939, and .9696, respectively). However, the two sets of linear regression equations obtained for wool and mohair were somewhat different, indicating that separate calculations should be used to estimate PM measurements from OFDA data. In conclusion, it was demonstrated that the OFDA instrument is capable of providing relatively fast, accurate, and potentially less expensive estimates of medullated fiber characteristics in mohair and wool.

The effect of zinc deficiency on wool growth and skin and wool follicle histology of male Merino lambs.

The aims of this work were to quantify the requirements of Zn for wool growth in growing male Merino lambs, and to describe the histological lesions of Zn deficiency in skin and wool follicles. Four groups of male Merino lambs (n 4) weighing 22 kg were fed ad lib. for 96 d on diets that contained 4 (basal diet), 10, 17 or 27 mg Zn/kg. Sheep in a fifth group were fed on the diet containing 27 mg Zn/kg, but were pair-fed to sheep on the 4 mg Zn/kg diet. Zn was added to the basal diet as ZnSO4 to give the respective treatment concentrations. Sheep fed on the diet containing 4 mg Zn/kg showed clinical signs of Zn deficiency and lower feed intakes and wool growth than sheep in the other groups. Their wool fibres were improperly keratinized and the wool follicles contained a higher proportion of apoptotic bodies than other groups. There was no evidence of parakeratosis and the rate of bulb-cell production was not affected. Sheep from other groups showed no clinical signs of Zn deficiency, and mean feed intakes and growth rates did not differ significantly between sheep fed on diets containing 10, 17 or 27 mg Zn/kg. However, wool growth was reduced in sheep fed on the diet containing 10 mg Zn/kg compared with those fed on diets containing 17 or 27 mg/kg. The mean concentration of Zn in the plasma at which wool growth was 90% of maximum was 0.5 mg/l. The equivalent value for the diet was 12 mg/kg, with 95% confidence intervals of 8 to 16 mg/kg. The results suggest that Zn deficiency reduces wool growth through a specific mechanism, perhaps involving impaired protein synthesis.

The effect of live weight gain and live weight loss on body composition of Merino wethers: dissected muscle, fat, and bone.

Sheep were slaughtered after live weight gain (LWG) and live weight loss (LWL) to evaluate the effect of different periods of normal and retarded growth on dissected carcass components. Thirty-five Merino wether sheep were allowed ad libitum access to the experimental diet of 80% alfalfa chaff and 20% cereal grain (17.23% CP and 18.10 MJ/kg of GE) to grow from 23.0 to 33.0 kg live weight and then fed to lose 10 kg at 133 g/d. Five animals were slaughtered at live weights of 23.0, 26.3, 29.6, and 33.0 kg during LWG and 29.6, 26.3, and 23.0 kg during LWL. Fleece-free empty BW was similar in both LWG and LWL animals at all common slaughter weights because of the lesser and greater weights of the alimentary tract contents and the fleece, respectively, in the LWL animals. Carcass weight or dissected side weight was greater in LWL animals at each common slaughter weight but significantly so (P less than .05) at the 23.0 kg live weight only. Total side muscle weight was similar in LWG and LWL animals at each common slaughter weight, but the proportion of muscle in the dissected side weight was lower (P less than .05) in LWL animals at 23.0 kg live weight. Total side fat, subcutaneous fat, intermuscular fat, and kidney and channel fat weights were all greater in LWL animals at each common slaughter weight, but significantly so (P less than .05) at the 23.0 kg live weight only. Total side bone weight was higher at both 26.3 kg (P less than .01) and 23.0 kg (P less than .05) in the LWL animals. Weight loss in young sheep mobilized more weight of muscle than fat from the carcass, whereas bone weight was constant.

Estimation of genetic parameters for wool fiber diameter measures.

Genetic and phenotypic correlations and heritability estimates of side, britch, and core diameters; side and britch CV; side and britch diameter difference; and clean fleece weight were investigated using 385 western white-faced ewes produced by 50 sires and maintained at two locations on a selection study. Data were analyzed using analysis of variance procedures, and effects in the final model included breed of sire-selection line combination, sire within breed-selection line, and location. Heritabilities were estimated by paternal half-sib analysis. Sires within breed-selection line represented a significant source of variation for all traits studied. Location had a significant effect on side diameter, side and britch diameter difference, and clean fleece weight. Age of ewe only affected clean fleece weight. Phenotypic and genetic correlations among side, britch, and core diameter measures were high and positive. Phenotypic correlations ranged from .68 to .75 and genetic correlations ranged from .74 to .89. The genetic correlations between side and britch diameter difference and side diameter or core diameter were small (-.16 and .28, respectively). However, there was a stronger genetic correlation between side and britch diameter difference and britch diameter (.55). Heritability of the difference between side and britch diameter was high (.46 +/- .16) and similar to heritability estimates reported for other wool traits. Results of this study indicate that relatively rapid genetic progress through selection for fiber diameter should be possible. In addition, increased uniformity in fiber diameter should be possible through selection for either side and britch diameter difference or side or britch CV.

Effects of skirting on processing characteristics of Targhee wool.

Ninety mature Targhee ewes were randomly allocated to nine lots. Lots were randomly assigned to three fleece preparation treatments: 1) nonskirted (control); 2) bellies removed, in which bellies and topknots were removed on the shearing floor; and 3) skirted, in which bellies and topknots were removed and remaining fleece was thrown on a table and lightly skirted. Bellies and topknots composed about 6 to 7% of the fleece weight. An additional 6.6% was removed when fleeces were skirted. Top fiber diameters were not affected (P greater than .10) by skirting. Although not significant (P greater than .10), percentage yield, vegetable content, percentage of noilage, top fiber length, and yellowness indexes tended to be most desirable for skirted lots and least desirable for unskirted lots. Lots with bellies removed were intermediate. Removal of bellies reduced vegetable contamination by 8.4%, with an additional reduction of about .5% by further skirting. Skirting reduced the number of fibers less than 25.4 mm (P less than .10) by 42%. Minimal colored fiber contamination of top was observed. One colored fiber per 15 g of top was detected in two lots of the treatment with bellies removed. All other lots contained no colored fibers. All wools evaluated were well below industry limits set for use in high-quality white or pastel fabrics. All skirted lots of wool evaluated in this study had improved processing characteristics for all processing traits evaluated.

Factors influencing difficulty of removing pelts from lamb carcasses.

Forty-eight Suffolk x white-faced ram and wether lambs approximately 5, 7, or 9 mo of age were slaughtered to evaluate the effects of age and gender on difficulty of pelt removal, pelt damage, and leg damage. A commercial belt-type pelt puller and a scale that recorded force required to remove the pelt from the thickest part of the legs was used as lambs hung suspended from their front legs. Rams required more force (P less than .05) to remove the pelt than wethers, and the difference between genders became larger as age increased. Neither pelt damage due to grain crack nor leg damage judged by amount of fell and fat removed by the pelt puller changed with age. Rams possessed thicker pelts (P less than .05) than wethers; this plus a greater amount of collagen crosslinking in ram skins could be responsible for the slightly smaller amount of grain crack observed in ram pelts. Factors involved in difficulty of pelt removal in ram lambs included age, splenius weight, and overall maturity. Difficulty of pelt removal in wether lambs was best predicted by including age and splenius weight in the model. These data tend to support packers' common practice of discounting rams over 5 mo of age because rams develop masculine characteristics and become harder to dress with increasing age.

Observations on fibre diameter variation of sheep in relation to fleece-rot and body strike susceptibility.

A comparative study of various fleece properties known to influence fleece-rot susceptibility was made in a merino flock consisting of sheep which were found to be either resistant or susceptible to fleece-rot and body strike following heavy rains. The fleece properties measured were fibre diameter, fibre diameter, fibre diameter variation, wax content, suint content, wax to suint ratio, suint pH, insoluble nitrogen content, wool colour and wettability. Fibre diameter variation, due mainly to the presence of coarse, secondary fibres in the staple, was the only fleece property which differed significantly (p less than 0.001) between resistant and susceptible animals. The coefficient of variation of fibre diameter was lowered from a mean value of 22.7 +/- 0.3% in susceptible sheep to 20.0 +/- 0.3% in resistant sheep. A causal relationship between high fibre diameter variation and fleece-rot susceptibility is suggested. Sheep with irregular fibre size may retain free moisture in the fleece for longer, and thereby become more susceptible to fleece-rot than sheep with uniform fibre diameter, other predisposing factors being equal.

Effects of abomasal supplements of methionine on the wool follicles and skin of wheat-fed sheep.

In wheat-fed sheep, supplemented abomasally with 1.5-6.0 g methionine per day, poor formation and improper keratinization of the wool fibres were evident 4 days after the start of the methionine supplementation. This led to kinking of the fibres. Subsequently severe distortion of the fibres, accompanied by gross thickening of the outer root sheaths, occurred in the distal (upper) halves of most follicles. Within this thickened region partial degradation of the distorted fibres occurred before emergence from the skin surface, causing a marked reduction in the tensile strength of the wool. It is postulated that kinking of the fibres stimulated the accumulation of outer root sheath cells, which led to hyperactivity of the process that normally degrades the inner root sheath, so that the poorly keratinized fibres were also partly degraded. Thickening of the epidermis and cellular infiltration of the upper dermis sometimes occurred during the infusions of methionine, whereas there were negligible effects on the sebaceous and sweat glands. Disappearance of the excess accumulation of outer root sheath cells after cessation of the methionine supplementation occurred gradually following improvement in keratinization and elimination of kinking of the fibres.

Regeneration of wool follicles in autografts of sheep skin.

Three experiments involving six sheep were carried out at three different times in the annual wool growth cycle. Forty-eight full-thickness fitted autografts were sampled 2 h, 6 h, 24 h, 48 h, 3, 4, 5, 7, 9, 11, 14, 21 and 28 days after grafting. The histopathology of the grafts is described. Individual variation in 'take' was probably related to the speed with which vascular integrity was reestablished between graft and bed. Delayed acceptance caused the death of pilosebaceous units. In a successful graft, wool follicle regeneration appears to occur in three main ways: (1) an inactive follicle regenerates from the dormant bulb at about seven days, (2) follicles that were active at the time of grafting have first to form a papilla stalk, and such follicles did not become active until 11 days, (3) sometimes one or more outgrowths appeared at higher levels suggesting follicle regeneration by branching. In addition there were a few instances of de novo downgrowth of follicle plugs from the epidermis. Wool growth on the graft therefore arises almost entirely from the reorganisation of preexisting follicles.