Fiber Growth Rate Research Articles

Development of myofibers and muscle transcriptomic analysis in growing Yili geese

In poultries, muscle growth is a quantitative trait controlled by multiple genes. The regulatory mechanisms governing muscle tissue growth and development in poultry, particularly during the early stages of growth, are intricate. Through the examination of leg muscle transcripts from Yili geese during various stages of development, this study offers valuable insights into the molecular mechanisms underlying the growth and development of Yili geese. This study aimed to perform a comparative analysis of the histological characteristics of leg muscles and the mRNA expression profiles of leg muscles in Yili geese at different ages (2, 4, 6, 8, and 10 wk). The objective was to identify differentially expressed genes related to muscle development in Yili geese and utilize bioinformatics to predict the potential biological functions of these genes. Through histological studies on leg muscle tissues, it was discerned that male geese at 4 wk exhibit a significantly reduced muscle fiber density in comparison to females (P < 0.01). In contrast, by the time they reach 6, 8, and 10 wk, their muscle fiber diameter and cross-sectional dimensions significantly outpace the females (P < 0.01). With the advancement in age, muscle fiber density tends to decrease. It is worth noting that 4- and 6-wk-old male geese have a substantially elevated muscle fiber density when matched against females (P < 0.01). Conversely, at the age of 10 wk, their muscle fiber density is notably inferior to the females (P < 0.01). Furthermore, male geese exhibit the most rapid increase in muscle fiber diameter and cross-sectional area between 4 and 6 wk of age. The density of muscle fibers in these geese significantly decreases from 4 to 8 wk. In contrast, female geese show the most pronounced growth in muscle fiber diameter and cross-sectional area between 2 and 6 wk, with a swift decline in density following the 6-wk mark, accompanied by a gradual reduction in the rate of muscle fiber growth. A comprehensive analysis of the leg muscle mRNA expression profiles from 12 Yili geese generated a cumulative total of 502,065,268 valid sequence reads, corresponding to a data volume of 75.30 Gb. In a comparative analysis between 4-wk-old and 2-wk-old groups (T4 vs. T2), 8-wk-old and 2-wk-old groups (T8 vs. T2), and 8-wk-old and 4-wk-old groups (T8 vs. T4), we identified 1,700, 1,583, and 221 differentially expressed genes (DEGs), respectively. Differentially expressed genes were significantly enriched in Gene Ontology (GO) terms such as organelle organization, cytoskeletal protein binding, cation transport, myosin complex, and actin cytoskeleton. Among the significantly enriched signaling pathways, 5 pathways were found to be significantly related to growth and development: adhesion patch, extracellular matrix receptor interaction, tight junction, TGF-β signaling pathway, and MAPK signaling pathway, with a total of 38 differentially differentiated genes contained in these 5 pathways, and it was hypothesized that the above pathways as well as the DEGs in the pathways played an important role in the regulation of early growth and development of the Yili goose. This investigation serves as a foundational reference for elucidating the molecular regulatory mechanisms involved in the development of goose muscle. Furthermore, it contributes to the expansion of the theoretical framework concerning the genetic regulation of muscle growth in geese.

The effect of polymerizable monomers on the thickness and the growth rate of self-assembled smectic fibers

Abstract Liquid crystal (LC) fibers formed by the self-assembly of LC molecules are promising for optical devices. However, the LC fibers reported previously were metastable and not reliable. In this study, we fabricated LC fibers using polymerizable monomers (PM). The growth rate decreased and the thickness increased compared to those of pure LC fibers. Our results will be useful for photopolymerization and will provide information for the application of the LC fibers.

Electrospun Fibers Loaded with Probiotics: Fundamentals, Characterization, and Applications.

Increasing demand for safe, efficient, and eco-friendly solutions for pharmaceutical and food industries has led researchers to explore new approaches to bacterial storage. Several advantages make electrospinning (ES) a promising technique for food systems, including simple manufacturing equipment, a relatively low spinning cost, a wide variety of spinnable materials, and a mild process that is easily controlled, which allows continuous fabrication of ultrafine polymeric fibers at submicron or nanoscales without high temperatures or high pressures. This review briefly describes recent advances in the development of electrospun fibers for loading probiotics (PRB) by focusing on ES technology, its efficiency for loading PRB into fibers (viability, digestive stability, growth rate, release, thermal stability, and interactions of fibers with PRB), and the application of PRB-loaded fibers as active packaging (spoilage/microbial control, antioxidant effect, shelf life). Based on the literature reviewed, the incorporation of PRB into electrospun fibers is both feasible and functional. However, several studies have been limited to proof-of-principle experiments and the use of model biological products. It is necessary to conduct further research to establish the industrial applicability of PRB-loaded fibers, particularly in the fields of food and medicine.

Inhibition of prolactin promotes secondary skin follicle activation in cashmere goats.

The aim of this study was to investigate the involvement of prolactin (PRL) on development of secondary skin follicles in cashmere goats. Goats were randomly assigned to either a bromocriptine treatment or control group. Samples of cashmere fiber, blood, and skin were collected from all goats after 1 mo. The results indicated that the length, growth rate, and diameter of fibers were not influenced (P > 0.05) by the inhibition of PRL resulting from the treatment with bromocriptine. There was a tendency for increases in total follicle number, primary and secondary follicle numbers, and in the ratio of secondary to primary follicles following treatment with bromocriptine, but these differences were not significant (P > 0.05). The percentage of active secondary follicles in anagen was increased (P < 0.05) in the bromocriptine-treated goats, but there was no effect of treatment on the percentage of active primary follicles. Bromocriptine decreased (P < 0.05) circulating concentrations of PRL and Insulin-like growth factor 1 (IGF1) and increased (P < 0.05) those of melatonin (MT), but there was no effect of this treatment on the serum concentrations of cortisol, growth hormone, tetraiodothyronine, and triiodothyronine. In bromocriptine-treated goats, mRNA expressions of PRL and MT membrane receptor 1a (MTNR1a) were decreased (P < 0.05) and mRNA expression of MT nuclear receptor (RORα) was increased (P < 0.05), but there was no effect of the treatment on expression of long PRL receptor, short PRL receptor, MT membrane receptor 1b and IGF1. It is concluded that inhibition of PRL promotes secondary hair follicle development in the anagen phase, possibly by downregulating MTNR1a and up-regulating RORα gene expression in the skin.

Energy requirements for maintenance and growth of young pre-ruminant Angora goats

Abstract There is little information available on the nutrient requirements of suckling Angora kids weighing less than 10 kg which has resulted in nutrition recommendations being based on older, heavier and weaned goats. This experiment determined the energy intake of suckling Angora kids to estimate maintenance ME requirement (MEm) and ME required for growth (MEg) for 8 and 21 day old kids. Does were housed in individual pens in an outdoor feedlot from day 47 of pregnancy. Pregnant does experienced a range of controlled nutrition treatments providing a range in live weight and body condition at kidding. From 4 days postpartum treatments were: ad libitum (AL) to allow maximum ME intake resulting in doe live weight gain; or Restricted (R) to 70% of AL, resulting in doe live weight loss until week 10 of lactation. Doe milk production was determined at days 8 and 21 of lactation, and ME intake of milk, kid liveweight change and fibre growth rate were determined. ME intake (kJ/kg0.75day) was then related to daily liveweight gain (g/kg0.75day) using multiple linear regression analysis. At 8 days of age, MEm = 1199 kJ/kg0.75day and MEg = 35.6 kJ/kg0.75day (P = 0.002). At 21 days of age, MEm = 700 kJ/kg0.75day (NS) and MEg = 24.0 kJ/kg0.75day (P

Adding Appropriate Fiber in Diet Increases Diversity and Metabolic Capacity of Distal Gut Microbiota Without Altering Fiber Digestibility and Growth Rate of Finishing Pig.

The digestion ability of pigs to dietary fiber is derived from their intestinal microbiota, especially hindgut microbiota. However, tolerance of pigs to high dietary fiber and the changes of microbiota profile with fiber levels are still unclear. To investigate the changes of gut microbiota with dietary fiber and its relationship with fiber digestibility, we conducted comparative analyses of growth rate, apparent fiber digestibility, gut microbiota and volatile fatty acid (VFA) profiles in Chinese Suhuai pigs feeding diets with different defatted rice bran (DFRB) fiber levels. We found that dietary fiber level had no effect on the growth rate of Suhuai pigs. Although the apparent digestibility of Cellulose, insoluble dietary fiber (IDF) and total dietary fiber (TDF) decreased with dietary fiber level, we found that the apparent digestibility of Cellulose, IDF and TDF of Suhuai pigs was not changed when provided with diet containing 19.10% TDF (as feed basis). The pigs provided with diet containing 19.10% TDF had higher microbial richness, proportions of several fiber-degrading bacteria taxa at genus level and predicted microbial functions (such as carbohydrate metabolism, energy metabolism) in cecum compared to those fed with basal diet. In addition, the fiber-induced increasing of fiber-degrading bacteria promoted the VFAs metabolism, which potentially helped Suhuai pigs to maintain growth rate. However, as TDF reached to 24.11% (as feed basis), the apparent digestibility of fiber decreased and the positive effect on intestine microbiota in caecum were absent. Together, our data suggest that appropriate fiber level could increase the diversity and metabolic capacity of distal gut microbiota to improve the utilization efficiency of fiber resources without altering the growth rate of pigs.

Structural and mechanical characterization of carbon fibers grown by laser induced chemical vapor deposition at hyperbaric pressures

Laser induced chemical vapor deposition (LCVD) of freestanding carbon fibers from ethylene at hyperbaric pressures was investigated. Relationships between processing conditions, growth behavior, microstructure, and mechanical properties of the carbon fibers were established. It is found that the fiber growth rates are limited by surface reaction kinetics at low temperatures and limited by gas phase nucleation at high temperatures. At higher pressures and intermediate temperatures, growth becomes mass transport limited whereupon the fibers exhibit drastic changes in morphology and microstructure from a core-shell, smooth appearance to nodular formations. The tensile strengths of the carbon fibers grown by LCVD are generally poor due to the nature of graphitic carbon deposits. However, the Weibull modulus among the LCVD grown carbon fibers was found to be very high. Effects of processing conditions and microstructure on the fiber strengths are observed and discussed.

A facile self-catalyzed CVD method to synthesize Fe3C/N-doped carbon nanofibers as lithium storage anode with improved rate capability and cyclability

Uniform Fe3C/N-doped carbon nanofibers were successfully synthesized through a facile self-catalyzed CVD method by using acetylene as carbon source and Fe3O4 as iron source and autocatalytic template for the reaction under moderate preparation conditions. The experimental and theoretical calculation results demonstrate that Fe3C can improve the lithium storage performance of carbon nanofibers. Besides, the addition of PPy can not only control the growth rate of carbon fibers but also help to form uniform carbon fibers. As a result, the obtained Fe3C/N-doped carbon nanofiber composites display favorable electrochemical performance as an anode for lithium-ion batteries, which including satisfactory rate performance of 402 mA h g−1 under 1.2 A g-1, and good cycling stability of 502.3 mA h g-1 under 200 mA g-1 over 400 cycles. The introduction of Fe3C species and the uniform carbon fiber morphology are responsible for the long-cycling and high rate performance of materials.

Ultrasound Assessment of Muscle Injury Associated with Closed Limb Fracture.

Objective The aim of this study was to assess muscle injury associated with upper and lower closed limb fracture using ultrasound, and to develop ultrasound classification criteria for muscle injury. Patients and Methods Thirty patients with limb fracture and muscle injury participated in this study. Ultrasonography was used to assess muscle fibre, hematoma, vascular injury, and diameter growth rate. Injury was classified into three grades according to the ultrasound imaging: scores of less than, equal to, or greater than 9. Results Of 30 patients, focal fibre rupture was observed in 11 cases; in 9 cases, the injured area exceeded 30% of the muscle area. Six patients had muscle hematoma (the largest reaching 39 mm); in 4 patients, the hematoma showed a honeycombed pattern. Vascular rupture was observed in 6 patients, of which 2 had decreased main arterial diameter and blood flow. The greatest increase in muscle thickness was 17 mm. Of all patients, 11 showed an increase in the diameter growth rate of the muscle exceeding 50%. In addition, among the 30 patients, 11 patients with scores ranging from 4 to 8 received conservative treatment; 9 patients with scores ranging from 10 to 14 received operative treatment; and 10 patients with scores equal to 9 received either conservative or operative treatment. Conclusions Ultrasonography is useful for diagnosing muscle injury associated with closed limb fracture. The ultrasound classification criteria for muscle injury can be used to assess the severity of injury and guide the decision of treatment.

Variation in the KAP6-1 gene in Chinese Tan sheep and associations with variation in wool traits

The keratin-associated protein KAP6-1 gene (KRTAP6-1) was investigated for its effect on wool traits in Chinese Tan sheep. Two previously identified KRTAP6-1 variants (A and B) and two newly identified KRTAP6-1 variants (D and E) were detected with frequencies of 28.9%, 57.1%, 10.3% and 3.7% for A, B, D and E, respectively. The KRTAP6-1 variant C, was not found in the Chinese Tan sheep. Variant D was found to be associated with increased straightened fibre-length at birth, while variant E was found to be associated with increased straightened fibre-length, the number of crimps and the degree of crimping at approximately 35days post-partum (conventionally called “Er-mao”). Variant E was also associated with increased wool fibre growth rate from birth to Er-mao. These results suggest that variation in ovine KRTAP6-1 may affect wool traits in early life in Chinese Tan sheep.

Cuticle and cortical cell morphology and the ellipticity of cashmere are affected by nutrition of goats

Cuticle scale edge height and frequency are used to identify animal fibres but exhibit a large range in dimensions, the reasons for which have not been elucidated. Cuticle and cortical cell dimensions along with the ellipticity of fibres were investigated in cashmere samples from a controlled nutrition experiment. Cuticle scale frequency, cuticle thickness, cortical cell dimensions and ellipticity were affected by nutritional treatment, with significant differences between cashmere from goats fed to grow and those which maintained live weight or lost weight. Cuticle scale frequency, cell thickness and ellipticity (contour) varied with fibre diameter, fibre growth rate and the size of the animals. Cuticle thickness and ellipticity were related. Cashmere grown by goats with higher levels of nutrition had longer cortical cells with greater diameter, volume and a higher length:diameter ratio compared with cashmere grown by goats in restricted nutrition treatments. The results show that the fundamental physical structures of cashmere do not have fixed dimensions. The consequences of the variations in cuticle morphology and ellipticity will be variation in surface friction, bending rigidity, softness, lustre, colour attributes, fibre cohesion during processing, felting and wear properties of textiles. There are also important consequences upon the determination of cashmere origin.

Variation in the KAP8-2 gene affects wool crimp and growth in Chinese Tan sheep

The keratin-associated protein KAP8-2, is present in wool from sheep. The effect of variation in KRTAP8-2 on wool traits was investigated in Chinese Tan sheep. Two previously identified KRTAP8-2 alleles (A and B) were detected, but the frequency of B in the Tan sheep was much higher than reported previously for New Zealand (NZ) sheep. Variant A was found to be associated with both a decrease in straightened fibre-length and the ratio of straightened length to crimped length at day-35 post-partum (conventionally called ‘Er-mao’). A trend was evident between the presence/absence of A and crimped fibre-length at Er-mao, and between the presence/absence of A and fibre growth-rate from birth to Er-mao. This suggests that variation in ovine KRTAP8-2 may affect wool crimping and growth in the early life of Tan sheep.

Influence of nutrition supplementation on the seasonal change in fiber growth and skin follicle activity in both male and female Sanjabi lambs

The present work aimed to investigate the effect of nutrition supplementation on skin follicle activity and wool growth rate in male and female Sanjabi lambs during the autumn and winter seasons, when the natural daylength is declining and being shortest. Twenty male (control and male (CM), n=10; treatment and male (TM), n=10) and 20 female (control and female (CF), n=10; treatment and female (TF), n=10) Sanjabi lambs were housed in individual pens, under natural daylength condition at west of Iran, Kermanshah (34°18′ N and 47°3′ E and 1420m above sea level). Lambs in control groups received a diet consisting of 80% alfalfa and 20% concentrate, providing 2.18Mcal and 130.0g per kg DM ME energy and crude protein, respectively. In treatment groups, lambs were fed a diet consisting of 65% alfalfa and 35% concentrate, providing 2.34Mcal and 160.0g per kg DM ME energy and crude protein, respectively. Raw and clean fiber growth rates and fiber diameter were measured from left mid-side patches harvested at the end of every month. Percentage of active primary and secondary follicles (PAP and PAS), follicular density (FD) and the ratio of secondary to primary follicles (S/P) were measured from skin biopsies, taken from the right mid-side of the lambs in monthly intervals. PAP and PAS in autumn were significantly (p<0.01) higher than those observed in winter season. There was a positive effect of feeding supplementation on both PAP and PAS but, similar values for S/P ratio and FD were observed in control and treatment groups. All hair follicle parameters viz. PAP, PAS, S/P ratios and FD were significantly greater in females compared to male lambs. The rate of wool growth was significantly lower in winter compared to autumn season, although similar fiber diameter was recorded in two seasons. Male lambs compared to females had greater body weight, DMI and the rate of wool growth. It is concluded that the fiber follicle activity and therefore wool growth in Sanjabi lambs is mainly under influence of nutrition, nonetheless little monthly fluctuation in follicle activity and fiber growth and diameter was observed. Likewise, there was a different pattern of wool production in male and female Sanjabi lambs.

Study of catalytic properties of sol-gel-derived CoO x -SiO2 film systems by the example of the growth of carbon nanomaterials

Film catalytic samples in the Si-Co-O system in the composition range from 15 to 90 mol % Co have been prepared using the sol-gel technology. Carbon nanomaterials have been fabricated by pyrolytic synthesis using these films as catalysts. Raman spectroscopy of materials has shown that multiwalled carbon nanotubes are formed by pyrolysis on catalytic films containing Co3O4. The dependence of the carbon material length on the synthesis time has been considered. It has been shown that the average growth rate of tubes and fibers is ∼3 μm/min.

Coaggregation of Two Anionic Azo Dyestuffs: A Combined Static Light Scattering and Small-Angle X-ray Scattering Study.

The formation of azo dyestuff aggregates in dilute aqueous solution induced by the addition of Mg2+, Ca2+, Sr2+, or Ba2+ ions is followed by time-resolved static light scattering (SLS) and time-resolved small-angle X-ray scattering (SAXS). Time-dependent molar mass data of the growing aggregates is interpreted by means of a kinetic model introduced by Lomakin et al. ( Proc. Natl. Acad. Sci. U.S.A. 1996 , 93 , 1125 ) for the description of β-amyloid aggregation. This interpretation reveals significant trends within the homologous series of alkaline earth cations. The trends refer to the nucleation and the growth rate of the dyestuff fibers. Time-resolved SAXS experiments indicate that these first two stages are followed by a third one during which a network forms by partial lateral alignment of fibers. At high enough dyestuff concentrations, this network formation even leads to a gel-like phase. Anomalous SAXS (ASAXS) on such a gel phase formed upon the addition of Sr2+ revealed the extent of neutralization of the dyestuff molecules within the gel by the specifically interacting alkaline earth cations.

Tuning the architecture of three-dimensional collagen hydrogels by physiological macromolecular crowding

Macromolecular crowding is an optimal physiological feature in intracellular and extracellular spaces, and results from a variety of macromolecules occupying space and contributing to a fractional volume occupancy. Here, we show that soft collagen hydrogels assembled in nature-inspired crowded conditions feature enhanced biophysical properties. We demonstrate that crowding tunes the rate of collagen nucleation and fiber growth, affecting fiber diameter and organization. Adjustments of crowding levels during collagen assembly tune the gel pore size, protein permeability, transparency and resistance to enzymatic degradation. Furthermore, gels assembled in crowded conditions are twice as resistant to mechanical stress as the controls, inducing a 70% boost of proliferation of stem cells cultured on tuned hydrogels. Emulating the crowdedness of interstitial fluids therefore represents a way to optimize the properties of soft collagen gels, with promising applications in soft biomaterials design.

On “how to start a fire”, or transverse forced-convection, hyperbaric laser chemical vapor deposition of fibers and textiles

This work explores the transverse forced flow of precursor gases during hyperbaric pressure laser chemical vapor deposition (HP-LCVD). Axial and mass growth rates of carbon fibers are measured experimentally, and a numerical model is developed that provides fiber growth rates in both the mass-transport-limited (MTL) and kinetically limited (KL) regimes. It is found that the fiber’s transport-limited rate increases as the square root of the flow velocity, while simultaneously, the temperature drops with the inverse square root of the flow velocity. Growth is enhanced by forced flow so long as the reaction zone remains within the MTL regime; upon reaching a critical temperature and flow rate, however, fibers enter the KL regime, and the growth rate declines with rising flow rate. Molecular properties of the precursors employed and gas concentrations ultimately determine the range of the MTL and the locations of the critical temperature and flow rate. The growth rates of fibers can indeed be enhanced by transverse forced convection—to at least three times the zero-flow steady-state rate, provided an MTL regime exists. Complex three-dimensional structures may be grown from these fibers in a freeform manner, and the more rapidly such microstructures can be fabricated, the more practical HP-LCVD becomes for industrial use, including the fabrication of novel textiles.

Responses to betaine and inorganic sulphur of sheep in growth performance and fibre growth

Sulphur-containing amino acids (SAA) are essential and usually the first limiting amino acids for growth, milk and wool production. The keratin fibre that grows from epidermal tissue is rich in SAA. The rate of fibre growth and its S content are influenced by the availability of SAA. Betaine is a dietary source for a labile methyl group and actively participates in methionine metabolism by donating methyl groups for the remethylation of homocysteine to methionine. Ruminants are capable of synthesizing SAA from inorganic S sources, and most bacteria in the rumen can use inorganic S to meet their requirements for growth. The objective of this study was to examine whether betaine and an inorganic sulphur supplement could provide methyl groups and sulphur amino acids in a way that growth performance and wool production of ewes and lambs are improved. Treatments performed included betaine supplementation, sulphate supplementation and betaine plus sulphate supplementation with five replications for each treatment. The dry matter intake of the ewes was affected by betaine plus sulphate supplementation (p < 0.05). In the ewes, betaine plus sulphate supplementation increased (p < 0.05) the wool growth rate, wool yield, staple length and wool sulphur concentration, while decreasing wool wax and wool yellowness (p < 0.05). In the lambs, wool growth rate, wool yield, fibre diameter, staple length, staple strength, wool sulphur concentration, wool wax and fibre percentage did not differ (p > 0.05) between treatments. In the ewes, plasma methionine concentration increased (p < 0.05) with betaine plus sulphate treatment. No corresponding difference (p > 0.05) was observed in plasma methionine concentration in the lambs. It can be concluded that betaine plus sulphate supplementation has the potential to change wool characteristics in the ewes, while these compounds were without any effect on growth and wool production of the lambs. Combining the two supplements was advantageous.

Effect of genotype and sex on fiber growth rate of alpacas for their first year of fleece production

The sale of alpaca fiber is the main income for thousands of families in the Central Andes of Peru. Little information exists on the fiber length growth rate of alpaca (FLG), especially throughout their first year of life when the fiber is most valuable. We aimed to determine the monthly FLG of 22 alpaca offspring of two genotypes (9 Suri, 13 Huacaya) and considering sex differences (10 females, 12 males) in the High Andes of Peru. FLG growth was determined using dye-bands. An additive lineal model with three factors (genotype, sex, month) was used for statistic analysis. To evaluate the effect of genotype and sex on the profile of the FLG throughout the year a two factor repeated-measures model was used. The results showed that FLG was affected by genotype and month but not sex. The Suri genotype had 20% higher FLG than Huacaya genotype alpacas (1.34 vs 1.10 cm/month, P < 0.001). FLG increased over each of the first three months (P < 0.05) and then maintained a near constant rate for the remainder of the first year. The resulting staple length indicates that shearing at ages from 8 to 12 months of age will provide fleeces of sufficient length for textile processing.

The effects of agroforestry practices on fiber attributes in Populus nigra var. betulifolia

The effects of intercropping with alfalfa and initial tree spacing on fiber properties in Populus nigra var. betulifolia are reported on the basis of a study of 15 trees. The trees were harvested from an agroforestry trial near Karaj city, Iran. Treatments included four initial spacings of 3 m × 4 m, 3 m × 6.7 m, 3 m × 8 m, and 3 m × 10 m intercropped with alfalfa as nitrogen-fixing plant, as well as one 3 m × 4 m treatment without alfalfa. Results showed that initial spacing and intercropping with alfalfa increased the growth rate. Also, alfalfa-intercropping had increasing effects on all fiber dimensions, especially on diameter and wall thickness. The effect of initial spacing on fiber attributes based on ring numbers was not statistically significant; however, whole-disk fiber length, weighted by ring area, was increased with stem diameter. The reason for this increase may be traced to the fact that much of the basal area of fast-growing trees is concentrated in farther rings from the pith that have longer fibers. Clear correlation was not found between fiber length and growth rate and therefore, no firm conclusion can be made in this regard.