Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Wool”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2026

Genome-wide association study reveals candidate genes associated with body weight and wool traits in Ordos fine-wool sheep.

BACKGROUND: The Ordos fine-wool sheep is a high-quality fine-wool breed in China, renowned for its excellent wool quality, meat production, and adaptability to the arid and semi-arid regions of Inner Mongolia. Body weight and wool traits are important economic characteristics in sheep breeding. This study aimed to identify genetic loci associated with body weight (BW), wool length (WL), and wool fineness (WF) in Ordos fine-wool sheep. METHODS: A genome-wide association study (GWAS) was conducted in 388 Ordos fine-wool sheep genotyped using the GenoBaits® Ovine 40K SNP panel. Single nucleotide polymorphisms (SNPs) associated with BW, WL, and WF were identified, and candidate genes located near the SNPs reaching the suggestive threshold were subjected to functional annotation and enrichment analysis. RESULTS: A total of 22 SNPs were identified as potentially associated with BW, WL, and WF traits, corresponding to 27 annotated genes. Functional annotation highlighted six potential candidate genes, including LAMA2, ARHGAP18, IGFBP2, IGFBP5, CA10, and AXIN1, which may play important roles in regulating body weight and wool growth in sheep. CONCLUSIONS: The identified genes provide valuable candidate loci for BW, WL, and WF traits in Ordos fine-wool sheep. The results of this study provide preliminary references for further exploration of the genetic mechanisms of wool traits in Ordos fine-wool sheep and the development of molecular breeding markers.

GWAS↗
PubMed2026

Large-scale low-coverage whole-genome sequencing reveals the genetic architecture of wool and growth traits in fine-wool sheep.

Breeding sheep with superior growth performance and wool quality is essential for the sustainability of the fine-wool sheep industry. In this study, we perform low-coverage whole-genome sequencing (lcWGS) on 3842 individuals from 5 sheep breeds (4 fine-wool and 1 semi-fine wool) and generate a large genomic dataset. By comparing these breeds with coarse-wool sheep, we characterize the genomic landscape and selection signatures of fine-wool sheep. We identify several known functional genes associated with hair follicle development and skin morphology, including EGFR, KRT74, EDAR, EREG, and GLI2. Furthermore, GWAS of 19 traits identifies 156 candidate genes significantly associated with growth and wool characteristics, including LCORL for body size, EGFR for clean wool yield, and PRDM1 for fiber diameter. Notably, EGFR is detected in both GWAS and selection signature analyses, indicating its important role in phenotype formation and historical selection. Overall, our findings reveal the genetic basis of growth and wool traits in fine-wool and semi-fine wool sheep, highlight EGFR, LCORL, and PRDM1 as candidate genes, and provide valuable genomic resources and candidate markers for future functional validation and molecular breeding.

Body size↗
PubMed1992

Effects of skirting on yield, fineness, and value of wool from fine-wool range ewes.

Eighty-one mixed-age (2 to 8 yr old) Rambouillet ewes (58.5 kg, SD 5.9 kg) were randomly assigned to three treatment groups that contained similar numbers to study the effects of wool skirting on clean yield, fiber diameter, and prices received for fine wool. The sheep were managed as a single flock on an experimental ranch close to Barnhart, TX during the 4-yr study. Two fleece-skirting techniques (SK1 and SK2) were compared with a control procedure in which fleeces were not skirted before packaging (original bag, OB method). Skirted wools were higher yielding (P < .05) and contained less vegetable matter (P < .05) than skirts. However, clean yield and vegetable matter content of skirted and OB wools were not different (P > .05). Weight-averaged prices received for grease wool from the SK1, SK2, and OB treatments over the 4-yr period were 4.49, 4.36, and 3.83 $/kg, respectively. Prices received for both types of skirted wool plus skirts were higher (P < .05) than prices received for OB wool.

Animal Husbandry↗
PubMed1992

Effects of pinealectomy on wool growth and wool follicle density in merino sheep.

There is evidence to indicate that pinealectomy may enhance wool growth in the sheep. The aim of this study was to determine the effect of pinealectomy on wool growth and wool follicle density in Merino sheep. Castrated Merino rams (4 months old) were either pinealectomized (P), sham-pinealectomized (S) or not treated (C). Wool growth on mid-side patches was measured every 4 weeks and follicle density was monitored in skin biopsies collected before treatment and at regular intervals for 60 weeks. Venous blood samples were taken on each of these occasions for prolactin analysis. Melatonin concentrations were determined in venous blood collected pre- and posttreatment from samples taken over a 24-hr period during the winter solstice. Pre- and posttreatment plasma melatonin levels (mean +/- SEM) 65 +/- 17 and < 13 pg/ml for P, 86 +/- 21 and 69 +/- 20 pg/ml for S, and 94 +/- 41 and 122 +/- 37 pg/ml for C, respectively, indicated that the pineal glands had been successfully removed. Wool growth, total follicle density and liveweight (mean +/- SEM) did not differ between treatment groups. Measurements at week 60 were 3.9 +/- 0.3, 4.1 +/- 0.2, and 3.8 +/- 0.3 gm clean wool/100 cm2; 66 +/- 6, 69 +/- 7, and 64 +/- 3 follicles/mm2; and 50.4 +/- 1.3, 50.8 +/- 1.4, and 52.6 +/- 1.1 kg liveweight for groups P, S, and C, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1976

Metabolism of cystine by Merino sheep genetically different in wool production IV. Rates of entry of cystine into plasma, measured with a single intravenous injection of L-[35S]cystine, and the subsequent incorporation of 35S into wool fibres.

Ten, 2-year-old Merino ewes from a flock selectively bred for high clean fleece weight (Fleece Plus) and ten from a flock bred for low clean fleece weight (Fleece Minus) were randomly divided between two dietary treatments: 600 or 1100 g/day of pelleted lucerne hay. After 14 weeks, each ewe received an intravenous injection of L-[35S]cystine (66-4 muCi). Venous blood samples were collected at 15 specified times until 8 h after the injections, and wool fibres were plucked until 65-75 days after the injections. Protein-free filtrates prepared from blood plasma were bulked within sample times for ewes from the same flock and dietary treatment. Equations relating the specific radioactivity of free cystine isolated from the bulked filtrates to time after injection contained three exponential terms. The entry rate and pool size of cystine estimated from these equations were greater in Fleece Minus than in Fleece Plus ewes (by 25 and 44% respectively for entry rate and pool size). Both traits were also higher in ewes offered 1100 g lucerne/day than in those offered 600 g/day (58-7 v. 33-9 mg/h for entry rate and 19-2 v 11-8 mg for pool size). The concentration of free cystine in plasma was greater in ewes offered 1100 g lucerne/day (3-0 v 2-1 mg/1; P less than 0-05), and greater in Fleece Minus ewes (3-0 v. 2-1 mg/l; P less than 0-05). The percentage of the injected radioactivity recovered in the wool clipped to day 70 post-injection differed between genotypes and between dietary treatments (P less than 0.05), being greater in Fleece Plus than in Fleece Minus ewes, and greater in those offered 1100 g lucerne/day than in those offered 600 g/day. The relationships between 35S incorporated per 1000 fibres (R) and time after injection (t) were best fitted by equations of the form (formula: see text). For all sheep, n = 3. The coefficient of the second term was significantly greater (P less than 0-05) in ewes offered 1100 g lucerne/day, whilst the constant of this term was significantly greater in Fleece Minus ewes. The specific radioactivities of cystine incorporated into wool fibres (SRf) during various intervals of time after injection were derived from these equations and from the measured rates of output of cystine in wool. The equations computed to relate SRf to time after injection (t) were of the form (formula: see text). Again there were three components. The coefficient of the third component was significantly greater (P less than 0-05) in ewes offered 1100 g lucerne/day, whilst the constant of the second term was significantly greater in Fleece Minus ewes.

Animals↗
PubMed1976

[Variability and inheritance of behavior in fine-wool sheep. II. Character of inheritance of domesticated behavior and correlation of behavior with productivity traits in fine-wool sheep].

The results of an experimental study of the inheritance of individual behaviour in various types of crosses are presented; the phenotypic and genetic correlations between the behavior and producutivity characters in sheep and the possibility of applying behaviour characteristics to the selection process of fine-wool sheep are analysed. It is shown that the progeny from crosses between parents with the same type of behaviour inherits mainly the type of behaviour of their parents and that, in general, the inheritance has a polygenic character. A genetic relation between the type of domestic behaviour and the productive characters of fine-wool sheep is established. The genetic correlation coefficient between the behaviour and the wool productivity is 0,57, and that between the behaviour and the live weight is 0,53. It is concluded that the inheritance component contributes to the formation of the type of domestic behaviour of fine-wool sheep. Phenotypic and genetic correlations between the type of behaviour and the main productivity characters are discussed. The posibility of using behaviour characteristics as a character under selection is considered.

Animals↗
PubMed1978

The administration of flumethasone, by three different routes, its measurement in the plasma and some effects on wool growth in Merino wethers.

Flumethasone was given to Merino wethers weighing 30-50 kg at rates of 0.62-1.35 mg/kg(0.75) by intravenous (experiments 1 and 2), intraruminal (experiment 4) and subcutaneous (experiment 5) routes over 8 days. In experiment 3, 1.2 mg flumethasone/kg(0.75) was given intravenously over 4, 5 or 6 days. The plasma concentration profiles showed concentrations in the order: intravenous greater than subcutaneous greater than intraruminal. Plasma concentration patterns usually were highest during the first 48 h of infusion followed by relatively stable values. This last feature was not evident in experiments when the rate of hormone infusion was increased. Estimates of the metabolic clearance rates for flumethasone in experiments 1, 2 and 5 were 200-700 ml/min during the equilibrium concentration periods. The effects of flumethasone on some aspects of wool growth revealed interactions between the routes of administration, the period of dosage and the rate of wool growth in the recipients. In experiments 1 and 2 intravenous infusion of 1.20-1.33 mg flumethasone/kg(0.75) caused the shedding of all wool fibres about 30 days after treatment. Some effects of dosing sheep with flumethasone at a time when wool growth was decreasing were also observed in experiment 2. Flumethasone given at a rate of 1.2 mg/kg(0.75) over 4, 5 or 6 days caused the shedding of only some wool fibres which were firmly retained on the sheep by the continuous fibres. Intraruminal and subcutaneous infusions of 0.62-1.35 mg flumethasone/kg(0.75) had similar results to the last in the majority of animals although in a few cases no discontinuity of wool fibres was observed. Recovery in wool growth was observed after treatment. Animals regained their pretreatment wool growth in experiments 1, 4 and 5 by 60 days after treatment and probably equalled at that time wool growth in controls. Recovery was retarded in some individuals in experiment 2 and in some groups in experiment 3. In experiment 1, 21 days wool growth was estimated to have been lost. Some aspects of complete versus partial shedding of wool fibres are discussed particularly with reference to wool harvesting. Some similarities in the appearance of fleeces of steroid-treated sheep and naturally shedding animals are also discussed. In some experiments, particularly when the infusion rate of flumethasone was increased (experiment 3), the sheep showed temporary but significant feed refusals during, but more commonly after, treatment. Speculative discussion as to the metabolic causes of this response is included.

Animals↗
PubMed1991

Carcinogenicity of the insulation wools: reassessment of the IARC evaluation.

In assessing the health evidence concerning man-made mineral fibers, the chemical composition, surface activity, durability, and size of fibers have to be taken into account. Special-purpose fine glass fibers need to be separated from the insulation wools (glass, rock, and slag wool). The epidemiological evidence is sufficient to conclude that there has been no mesothelioma risk to workers producing or using glass wool, rock wool, or slag wool. The epidemiological studies have been large and powerful, and they show no evidence of a cause-effect relationship between lung cancer and exposure to glass wool, rock wool, or slag wool fibers. There is some evidence of a small cancer hazard attached to the manufacturing process in slag wool plants 20 to 50 years ago, when asbestos was used in some products and other carcinogenic substances were present. However, this hazard is not associated with any index of exposure to slag wool itself. Animal inhalation studies of ordinary insulation wools also show that there is no evidence of hazard associated with exposure to these relatively coarse, soluble fibers. The evidence of carcinogenicity is limited to experiments with special-purpose fine durable glass fibers or experimental fibers, and only when these fibers are injected directly into the pleural or peritoneal cavity. Multiple chronic inhalation studies of these same special-purpose fine glass fibers have not produced evidence of carcinogenicity. It is suggested that the present IARC evaluation of the carcinogenic risk of insulation wools should be revised to Category 3: not classifiable as to carcinogenicity to humans.

Animals↗
PubMed1991

Injurious effects of wool and grain dusts on alveolar epithelial cells and macrophages in vitro.

Epidemiological studies of workers in wool textile mills have shown a direct relation between the concentration of wool dust in the air and respiratory symptoms. Injurious effects of wool dust on the bronchial epithelium could be important in causing inflammation and irritation. A pulmonary epithelial cell line in vitro was therefore used to study the toxic effects of wool dust. Cells of the A549 epithelial cell line were labelled with 51Cr and treated with whole wool dusts and extracts of wool, after which injury was assessed. Also, the effects of grain dust, which also causes a form of airway obstruction, were studied. The epithelial injury was assessed by measuring 51Cr release from cells as an indication of lysis, and by monitoring cells which had detached from the substratum. No significant injury to A549 cells was caused by culture with any of the dusts collected from the air but surface "ledge" dust caused significant lysis at some doses. Quartz, used as a toxic control dust, caused significant lysis at the highest concentration of 100 micrograms/well. To determine whether any injurious material was soluble the dusts were incubated in saline and extracts collected. No extracts caused significant injury to epithelial cells. A similar lack of toxicity was found when 51Cr labelled control alveolar macrophages were targets for injury. Significant release of radiolabel was evident when macrophages were exposed to quartz at concentrations of 10 and 20 micrograms/well, there being no significant injury with either wool or grain dusts. These data suggest that neither wool nor grain dust produce direct injury to epithelial cells, and further studies are necessary to explain inflammation leading to respiratory symptoms in wool and grain workers.

Animals↗
PubMed1991

The characteristics of respiratory ill health of wool textile workers.

The relations of lung function and chest radiographic appearances with exposure to inspirable dust were examined in 634 workers in five wool textile mills in west Yorkshire, randomly selected to represent fully the range of current exposures to wool mill dust. Most of these workers could be categorised into three large sex and ethnic groups; European men, Asian men, and Asian women. Exposures to inspirable dust had been measured at a previous survey and time spent in current job, and in the industry were used as surrogates for lifetime cumulative exposures. Chest radiographs were interpreted on the International Labour Office (ILO) scale by three medically qualified readers, and the results combined. Profusions of small opacities of 0/1 on the ILO scale, or greater, were present in only 6% of the population, and were not positively associated with current exposure to wool mill dust, or duration of exposure. In general, statistically significant relations between exposure and lung function indices were not found, with the exception of an inverse relation between the forced expiratory volume/forced vital capacity ratio and dust concentration in European women. A suggestive but not statistically significant inverse relation between FVC and current dust concentration was seen in Asian men. Substantial differences were found between mills in mean values of lung function variables after adjustment for other factors but these were not apparently related to the differences in dust concentrations between these mills. Dyeworkers and wool scourers (mostly European men in relatively dust free jobs) on average experienced an FEV1 251 ml lower than other workers when age, height, smoking habits, and occupational factors had been taken into account. Twenty four per cent of the workforce responded to intracutaneous application of one or more common allergens (weal diameter at least 4 mm), only 12 (7.9%) of these responding to wool extracts. Atopic subjects did not appear to have an increased susceptibility to the effects of inspirable wool dust on lung function. These studies suggest that exposure to wool mill dust may cause functional impairment in some workers but there is little indication from these data of frequent or severe dust related functional deficits. More detailed estimates of cumulative dust exposure by reconstruction of exposure histories might clarify associations between exposure to dust and lung function. These chest radiographic findings provide no evidence that exposure to wool mill dust is related to lung fibrosis.

Adult↗
PubMed1992

In vitro and in vivo evaluation of cotton wool filtration of platelet concentrates obtained by automated and manual apheresis.

The effect of cotton wool filtration of apheresis platelet concentrates (PCs) on platelet viability and complement activation was evaluated by two laboratories. PCs were prepared by automated (Lab A, n = 5) or manual (Lab B, n = 5) apheresis. After storage for 1 day, the PC was filtered through cotton wool before transfusion on one occasion and, on the other occasion, filtered through a standard screen filter before transfusion to the same donor. Five paired studies were performed by each laboratory. Except for a small, but significant reduction in mean platelet size, from 7.3 +/- 1.1 to 6.6 +/- 0.9 microns 3, after cotton wool filtration, no effect of filtration on various tests of in vitro platelet function and morphologic integrity was found. As demonstrated by autologous radiolabeled studies, no effect of cotton wool filtration on platelet viability was found by Laboratory B, while Laboratory A found a slight increase in the percentage of recovery from 59 +/- 4 to 68 +/- 13 percent, and a small reduction in survival, from 8.2 +/- 0.9 to 7.7 +/- 0.5 days after cotton wool filtration (p less than 0.05). Cotton wool filtration was associated with a slight increase in C3a levels found in manual apheresis PCs. Neither laboratory found any effect of cotton wool filtration per se on the recipients' white cell (WBC) counts or C3a and C5a levels after transfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1975

Effects of mimosine, a potential chemical defleecing agent, on wool growth and the skin of sheep.

Twenty-two Merino sheep were dosed with various amounts of L-mimosine, given either as an intravenous or an intraperitoneal injection, or as a continuous intravenous infusion for periods of 1-4 days. Single injections of mimosine (1-16 g) had no effect on the strength of wool, and wool growth rates were not appreciably altered by injections of small amounts (4 g or less). Injections of larger amounts slightly reduced both length growth rate and diameter of tibres during the 4 days after dosing. The effects of intravenous infusions of mimosine depended on the rate and the duration of administration. Small amounts (0.5 or 1 g/day given for 4 days) has no effects on the strength of wool or on wool growth rates. Infusions of a total of 8 g, either at the rate of 2 or 8 g/day, weakened the wool but not sufficiently to allow the sheep to be defleeced. Both these treatments caused a temporary reduction in length growth rate and in diameter of fibres, and transient degenerative changes were observed in wool follicles. A region of the fibres representing 1-2 days' growth was constricted to about half the pre-infusion diameter when 8 g was given for 1 day. Infusions of at least 8 g mimosine over a period of 1 1/2-2 days were effective for defleecing all sheep dosed. This corresponded to a daily rate of infusion of about 80 mg/kg. No toxic effects were observed with infusions given for periods of 2 days. Defleecing was judged to be possible by 6-7 days after the start of infusion, and was readily carried out by about 14 days. Defleecing was associated with follicle retrogression and an abrupt cessation of wool growth within 2 days of the start of the infusions. It was estimated that fibre growth stopped for about 10 dyas; regrowth was first observed 17-18 days from the beginning of dosing. Low rates of infusion of mimosine (up to 2 g/day) resulted in plasma levels below 0.1 mmol/l. Infusion at the rate of 4 g/day or above, which produced defleecing, quickly resulted in levels of mimosine in plasma above 0.1 mmol/l; after 2 days the concentration was steady at aboug 0.2 mmol/l. Injections of 8 or 16 g mimosine resulted in very large, but transient, rises of the level in plasma.

Animals↗
PubMed1977

Comparison of wool reactions with selected mono and bifunctional reagents.

The molecular structure of wool is discussed in relation to chemical reactivity and the role of disulfide crosslinks. Ideal characteristics of an effective medium (e.g. dimethylformamide) for modifying wool include the ability to penetrate and swell wool without interfering with reagents used. The extent of reaction of wool or reduced wool is compared for mono-and bifunctional activated vinyl compounds, isocyanates, acid chlorides, acid anhydrides, sulfonyl chlorides, and alkyl halides. The degree of crosslinking is assessed by solubility, supercontraction, and tensile tests. Optical and electron scanning microscopy can give evidence of external polymer deposition in contrast to internal chemical modification. Effects of crosslinking by bifunctional reagents are related to changes in mechanical, chemical, and biological (moth-resisting) properties of the modified wool.

Animals↗
PubMed1991

Irritative symptoms and exposure to mineral wool.

In a cross-sectional study undertaken in 1981 using a postal questionnaire, the prevalence of irritative symptoms was investigated among 2,654 Danish construction workers working with mineral wool. An evaluation was undertaken in a multivariate logit analysis of the relationship between exposure level (measured by hours of exposure to mineral wool per month) and prevalence of symptoms. The analysis controlled for the confounders of age, smoking habits, and exposure to organic solvents. With greater exposure to mineral wool, there was a statistically significant increase in the frequency of irritative symptoms from the eyes, the skin, and the upper respiratory tract. Among construction workers working with mineral wool 160-180 hours per month, two-thirds had these symptoms once a week or oftener. The occurrence was 2-3 times higher compared with the construction workers not working with mineral wool. The relationship between exposure to mineral wool and skin and mucous membrane symptoms may be explained by the irritative action of the fibers that are given off during insulation work.

Adolescent↗
PubMed1991

A glass wool-based method for purifying Trypanosoma cruzi trypomastigotes and identification of an epimastigote-specific glass-adherent surface peptide.

Glass wool, hydrophilic cotton wool, non-electrically charged BIO-GEL P2 and common tissue paper columns were used to purify trypomastigotes from a mixed Trypanosoma cruzi population grown in axenic culture medium. With all these columns, highly purified (up to 98%) trypomastigote preparations were obtained. Trypomastigote yields from cotton wool, BIO-GEL P2 and common tissue paper columns were not as high as from glass wool columns, from which yields varied from 69 to 80%. Purification on glass wool did not affect trypomastigote infectivity or virulence. Dead trypomastigotes could not be purified on glass wool columns. A glass-adherent amphiphilic peptide of 45 kDa, present in the cell membrane, was isolated from epimastigote but not from trypomastigote preparations.

Animals↗
PubMed1975

Effects of intravenous infusion of mimosine on wool growth of Merino sheep.

Merino sheep were given continuous intravenous infusions of L-mimosine for periods of 1 1/2, 2 or 21 days; efficacy as a defleecing procedure and effects on subsequent wool growth were measured. In addition, the amino acids tyrosine, phenylalanine and cystine were investigates as antagonists to the effects of mimosine. Infusions for 1 1/2 or 2 days at the daily rate of 80-120 mg/kg caused a cessation of wool growth by 1 1/2-2 days from the start of infusion, and all sheep were subsequently defleeced. It was estimated that, on average, fibre growth stopped for 10 1/2-13 days in four sheep after a 2-day infusion, and for 5 1/2 and 9 1/2 days in two sheep after an infusion for 1 1/2 days. There was considerable variation in the time taken for new fibres to recommence growth. During the period 3-5 weeks after infusion of mimosine, length growth rate was consistently greater than the pretreatment rate. Likewise, fibre diameter was greater in three out of the four sheep. As a result, the volume growth rate of fibres was greater post-treatment than it was pretreatment. Infusion for 3 weeks at the daily rate of 21-24 mg/kg did not stop wool growth. However, both length growth rate and fibre diameter were considerably depressed, and after 12 days' infusion, fibre diameter and volume growth rate were reduced to less than half the pretreatment values, and wool fibres were very weak. After the mimosine infusion stopped, fibre diameter increased to above pretreatment values and remained ther for the period of 2-3 weeks studied. The concurrent infusion of tyrosine, phenylalanine or cystine with mimosine failed to prevent any of the effects of mimosine on wool growth.

Animals↗
PubMed1979

Studies on the in vitro metabolism of [3H]cortisol and [3H]oestradiol by sheep skin and wool roots.

The in vitro metabolism of [3H]cortisol, [3H]cortisone and [3H]estradiol-17 beta by adult sheep skin and wool follicle tissue (wool roots) was examined. The main metabolic product of the incubation of [3H]cortisol with sheep skin was [3H]cortisone, and the conversion was reversible. Wool roots were unable to carry out detectable interconversion, nor did this tissue give rise to other significant metabolites. Sheep skin and wool roots both rapidly converted [3H]oestradiol-17 beta to [3H]oestrone and the conversion could be carried out by follicle and non-follicle skin structures. It is suggested that sheep skin contains both 11 beta- and 17 beta-hydroxysteroid dehydrogenases, but that wool follicles contain only the latter enzyme.

Animals↗
PubMed1976

Effect of wool dust on respiratory function.

A group of 252 workers (176 women and 76 men) employed in two wool mills was studied. The mean age of 36 years; mean exposure, 11 years. All women were nonsmokers, and 47 per cent of the men were regular smokers. Ventilatory function was measured by recording maximal expiratory flow-volume curves and forced expiratory volume in 1 sec on the first working day of the week (Monday) before and after the work shift. On maximal expiratory flow-volume curves the flow rates at 50 per cent of the control vital capacity were read. Workers exposed to wool dust for more than 10 years had a higher prevalence of chronic respiratory symptoms than did those with less than 10 years' exposure, but the difference was not significant. Significant reductions during the work shift were found in maximal expiratory flow rates at 50 per cent of the control vital capapity and 1-sec forced expiratory volume, the first test being considerably more sensitive. Workers exposed to wool dust for more than 10 years had signficantly lower than predicted pre-shift values for maximal expiratory flow rates at 50 per cent of the control vital capapcity. Inhalation of wool dust extract caused a significant decrease of maximal expiratory flow rates at 40 per cent of the control vital capacity on partial expiratory flow-volume curves during the 100 min after exposure. Comparison with the same concentration of cotton dust extract revealed a similar effect during the first 40 min after exposure but a significantly larger effect of the cotton dust extract after 40 min. The data suggest that preventive measures, especially medical supervision, are necessary in wool-processing mills to protect workers sensitive to dust.

Adult↗