Cyclical fleece growth in cashmere goats

1987 ◽  
Vol 38 (3) ◽  
pp. 597 ◽  
Author(s):  
BJ McDonald ◽  
WA Hoey ◽  
PS Hopkins
Keyword(s):  
Volume Growth ◽  
Fibre Diameter ◽  
Continuous Light ◽  
Growth Period ◽  
Cycle Period ◽  
Circannual Cycles ◽  
Cumulative Length ◽  
Cashmere Goats ◽  
One Year ◽  
June July

Seasonal changes in fleece parameters were studied in mature feral doe goats, known to produce commercial quantities of cashmere and housed in natural light (NL) or continuous light (CL).Circannual changes in volume growth rate (VGR) of cashmere in NL were asynchronous with those of hair, resulting in maxima in April and November respectively, indicating that follicle-specific mechanisms are controlling the rate of follicle activities.Cycles of cumulative length of cashmere and hair in NL were synchronous. Cashmere maxima of 64.0 and 62.3 mm occurred in June and July respectively for two consecutive years. Distinct circannual cycles of linear growth (period, 365 days) were evident. While exposure to CL initially reduced the cycle period, after 2 years an extended cycle period emerged; this may have been due to photodesensitization.In NL, cashmere fibre diameter minima occurred at June-July and February each year. Hair fibres underwent only one cycle of diameter change each year. The period of the cycles was reduced by CL.An annual cycle of cashmere brush end fibre formation was apparent in NL. This cycle was associated with the cessation of growth in June-July, and a subsidiary event occurred between December and March. Continuous light accelerated brush end formation.Cyclic fibre shedding produced a circannual rhythm in fleece composition with maximum cashmere: hair ratio (CHR) in April-May in non-breeding goats. The maximum CHR of 5.9: 1 in NL did not reach its potential, as illustrated by the follicle S:P ratio of 6.9:1 in the skin. This suggests an irreversible loss of cashmere fibres from the fleece following the cycle of brush end formation in February.The maximum mean length of cashmere and time of occurrence were similar in grazing and penned does, although grazing does were only sampled in 4 months of one year.

Effect of photo-translation on fleece growth in cashmere goats

1987 ◽  
Vol 38 (4) ◽  
pp. 765 ◽  
Author(s):  
BJ McDonald ◽  
WA Hoey
Keyword(s):  
Growth Rate ◽  
Volume Growth ◽  
Continuous Light ◽  
Natural Light ◽  
Cyclic Activity ◽  
Cycle Amplitude ◽  
Pineal Function ◽  
Cashmere Goats ◽  
The One ◽  
Mean Cycle

Cyclical changes in fleece parameters were studied in mature feral doe goats exposed to either natural light (NL) followed by continuous light (CL) then NL, or CL followed by NL then CL.Results show that both initial translocations (NL-CL and CL-NL) were recognized immediately and reflected in changes in volume growth rate, length, diameter, brush end fibres of cashmere and cashmere : hair ratio. Cyclic activity continued after the change in photoperiod. Progressive alterations in cycle amplitude, period and frequency appeared in CL following the initial NL-CL change. Following the initial CL-NL change, cycles of some cashmere fleece parameters continued to be influenced by previous CL exposure and did not immediately adopt NL cyclicity. Mean cycle periods of 252-261 days were common to all CL photoperiods and to NL following CL. This suggests that CL exposes a unique cycle of fleece growth, which is independent of photoperiod and retained for some time after the cessation of CL, owing to transient modification of pineal function. Differences between the response to the first and second translocation may be a function of interactions between the cycle status and translocation, rather than solely the change from one photoperiod to another.The NL-CL change resulted in two cycles of cashmere growth in the 392 days following the initial translocation. This would allow two fleeces to be harvested during that time compared with the one expected in NL alone. Exploitation of this principle may represent an opportunity to increase cashmere production.

Growth of scale for juvenile coho salmon in the Bolshaya River (West Kamchatka)

2014 ◽  
Vol 176 (1) ◽  
pp. 62-84
Author(s):  
Victor F. Bugaev ◽  
Nadezhda V. Yarosh
Keyword(s):  
Body Length ◽  
Coho Salmon ◽  
Water Cooling ◽  
Seasonal Growth ◽  
Growth Season ◽  
Similar Time ◽  
The Third ◽  
One Year ◽  
June July ◽  
In The Beginning

Structure of scale is investigated for juvenile coho salmon. The samples were collected in the lower part of the Bolshaya River (West Kamchatka) in 2007-2012. The first scleritis bounding the central plate of scale is formed when body length of coho underyearlings achieves 38 mm, on average. In the investigated area, seasonal growth of scale starts and formation of next annuli of juvenile coho scale happens usually in the third 10-days of May: in the beginning of this period for one-year-old fish and in its end for two-years-old fish. The seasonal growth becomes slower again with water cooling in the last half of September, until its complete stagnation in October. Each scleritis forms in similar time, independently on age of juveniles: in 11.3 days for the underyearlings (data for in June-September), 10.1 days for one-year-old fish (data for June-September), and 11.2 days for two-years-old fish (data for in June-July). Additional zones of dense sclerites could form on the scale of juvenile coho within the growth season.

Third-Year Growth Response of Loblolly Pine to Eight Levels of Competition Control

1987 ◽  
Vol 11 (2) ◽  
pp. 91-95 ◽  
Author(s):  
Catherine G. Bacon ◽  
Shepard M. Zedaker
Keyword(s):  
Loblolly Pine ◽  
Growth Response ◽  
Volume Growth ◽  
Growing Season ◽  
Control Treatment ◽  
Growing Seasons ◽  
Best Response ◽  
Competition Control ◽  
Pinus Taeda L ◽  
One Year

Abstract The growth response of young loblolly pine (Pinus taeda L.) to different amounts of competition control was studied in plantations of three ages in the Virginia Piedmont. Eight competition control treatments involved the removal of all, two-thirds, one-third, or none of the hardwoodstems either with or without herbaceous weed control. Results after three growing seasons showed a significant increase in pine diameter and volume growth with competition control. Treatments combining woody and herbaceous control resulted in better pine growth than the same treatments withoutherbaceous control, in the two youngest stands. The best response, obtained with the two-thirds woody plus herbaceous control treatment, resulted in: a 100% increase in volume growth over the check plots in seedlings treated at the beginning of their second growing season in the field; a 93% increase in one-year-old seedlings; and a 53% increase in the growth of seedlings treated before the third growing season. South. J. Appl. For. 11(2):91-95.

THE STUDY OF CLIMATE EFFECTS ON THE NUT YIELD OF COCONUT USING PARSIMONIOUS MODELS

1998 ◽  
Vol 34 (2) ◽  
pp. 189-206 ◽  
Author(s):  
T. S. G. PEIRIS ◽  
R. O. THATTIL
Keyword(s):  
Sunshine Duration ◽  
Growth Period ◽  
Climate Data ◽  
Active Growth ◽  
Dry Matter Partitioning ◽  
Air Temperatures ◽  
Nut Production ◽  
Parsimonious Models ◽  
June July ◽  
Active Growth Period

The coconut yield is harvested in six picks per year at two-monthly intervals. The yield variation between and within years is very complex and this variability has not yet been explained. The analysis of long-term nut yield and monthly climate data: rainfall (RF), pan evaporation (EV), sunshine duration (SS), wind velocity (WV), minimum and maximum air temperatures (TMIN and TMAX), and relative humidity in forenoons and afternoons (RHAM and RHPM), using multivariate methods enabled the use of the variables TMAX, RHPM and EV as significantly important determinants (parsimonious set of variables) to represent the effects of climate on coconut irrespective of picks. Parsimonious models developed using these three variables explain how the development of bunches during the active growth period responded to climate variables without physiological parameters. The models are desirable where interpretation is concerned. The yields of picks one to six were determined by the climate variability during February, June, July, September, December and February respectively. Based on the models the proper timing of the use of some agronomic practices to enhance the productivity was recommended. A common model was also fitted (R2 = 0.81; p < 0.002) to estimate the annual yield 18 months in advance using EV, RHPM and TMAX. The three variables influence the microclimate around the crown of the palm for utilizing solar radiation in dry matter partitioning and thereby nut production. The method used to screen climatic variables so as to develop parsimonious crop–weather models using multivariate and univariate techniques can be used for other tree crops.

XI.—An Investigation into the Effects of Seasonal Changes on Body Temperature

1913 ◽  
Vol 32 ◽  
pp. 110-135 ◽  
Author(s):  
Sutherland Simpson
Keyword(s):  
Body Temperature ◽  
Rectal Temperature ◽  
Egg Production ◽  
Weather Conditions ◽  
Barometric Pressure ◽  
Temperature Curve ◽  
The Body ◽  
The Mean ◽  
One Year ◽  
June July

SummaryMonthly observations, extending over one year, were made on the rectal temperature of 114 domestic fowls (Gallus gallus, ♀) and records from forty-one of these were obtained for two years. Six different breeds were used, each located in a separate pen, all under similar conditions, and the mean temperatures for each group were plotted out to form an annual temperature curve. It was found that—1. The lowest temperatures occur in December, January, and February, and the highest in June, July, and August, corresponding in a general way with the temperature of the external air.2. Barometric pressure does not appear to have any influence on the body temperature of the hen.3. The curve of egg-production does not coincide with the annual temperature curve, the former reaching its highest level in April and May, the latter in June, July, and August.If we compare the mean rectal temperature at two periods of the year when the external or weather conditions are approximately the same (April-May and September-October), but when the vitality of the birds, as indicated by the curve of egg-production, moulting, etc., is at a maximum and minimum respectively, we find that the figures are practically identical. This would seem to show that cyclical bodily changes have little effect on body temperature as compared with outside influences.

Effect of stocking rate on fleece measurements and their relationships in merino sheep

1976 ◽  
Vol 27 (1) ◽  
pp. 163 ◽  
Author(s):  
DH White ◽  
BJ McConchie
Keyword(s):  
Fibre Diameter ◽  
Major Determinant ◽  
Stocking Rate ◽  
Merino Sheep ◽  
Wool Production ◽  
Rate Experiment ◽  
Fleece Weight ◽  
One Year ◽  
Staple Length

The wool characteristics of Merino wethers were measured for 6 years in a stocking rate experiment. The decline in fleece weight due to increasing stocking rate from 4.9 to 12.4 sheep per hectare was usually accompanied by a reduction in fibre diameter and staple length and an increase in staple crimp frequency. The magnitude of these responses differed considerably between years; in one year clean fleece weight was reduced by 50%, with an associated reduction of 5 µm in mean fibre diameter and one of 2 cm in staple length. In four of the six years of the experiment, variation in fibre diameter accounted for at least 50% of the variation in wool production between stocking rate treatments. The relationships between clean fleece weight and fibre diameter were similar between years, mean fibre diameter being reduced by about 1.8 �m for each kilogram reduction in clean fleece weight. Fibre diameter is the major determinant of wool price, and this information should improve the prediction of economic responses to changes in stocking rate.

Effect of DL-methionine supplementation on fleece growth by Australian cashmere goats

1987 ◽  
Vol 109 (1) ◽  
pp. 197-199 ◽  
Author(s):  
A. J. Ash ◽  
B. W. Norton
Keyword(s):  
Fibre Diameter ◽  
Maximum Length ◽  
Early Winter ◽  
Wool Growth ◽  
Mean Diameter ◽  
Fibre Growth ◽  
Cashmere Goats ◽  
Methionine Supplementation ◽  
Almost Continuous

Australian feral goats have recently been found to produce commercially viable quantities of the luxury fibre cashmere (Smith, Clarke & Turner, 1973). Cashmere is the fine down produced by secondary follicles as an undercoat during winter. Fibre diameter ranges from 8 to 24 μm with a mean diameter of 16 μm. Unlike modern breeds of sheep such as the Merino which exhibit almost continuous wool growth, cashmere growth is distinctly seasonal with fibre growth commencing in summer (long daylength) and reaching a maximum length in early winter (short daylength) (McDonald, 1985). The cashmere is cast in spring with growth recommencing again in summer.

Production and quality of cashmere grown by adult wether goats fed low quality forage with supplements of either whole barley or lupin grain.

2000 ◽  
Vol 40 (6) ◽  
pp. 795 ◽  
Author(s):  
B. A. McGregor ◽  
M. Z. Umar
Keyword(s):  
Fibre Diameter ◽  
Fibre Length ◽  
Late Summer ◽  
Experimental Period ◽  
Barley Grain ◽  
Practical Application ◽  
Whole Grain ◽  
Summer Pasture ◽  
Cashmere Goats

The effects of the provision of cereal (barley) and legume (lupin) grain supplements when 50 adult wether cashmere goats were individually penned and fed on senescent temperate summer pasture (DDM 46.9%, N 0.67%, ME 6.2 MJ/kg DM) were investigated using a factorial experiment. The goats grazed senescent temperate pasture during summer before pen feeding for 9 weeks and were then grazed on germinating autumn pastures for 3 months until shorn in mid June. The production and quality of cashmere was affected by: (i) provision of whole grain supplements, (ii) type of supplementary grain fed, and (iii) level of feeding of supplementary grain. Unsupplemented goats grew 95 g cashmere with mean fibre diameter 17.01 m and mean cashmere fibre length 52 mm. During the period of pen feeding unsupplemented goats lost 95 g liveweight/day. Provision of whole grain supplements significantly increased total yearly cashmere growth to 179 g (+88%) which was 26 mm longer (50%) and 2.12 m coarser (26%) than cashmere grown by unsupplemented goats. Increasing the level of supplementary grain resulted in linear increases in feed intake, cashmere growth, fibre diameter and length. For each 100 g/day of lupin or barley grain fed during the pen-feeding period the regression coefficients indicated an extra 33 g of cashmere was grown, which was 0.6 m coarser and for barley 10 mm longer and for lupins 17 mm longer. Cashmere (fibre length/fibre diameter2) ratio was increased by supplementary feeding, increased feed level and liveweight gain during the experimental period. Relatively longer cashmere was produced as the level of nutrition increased. It is clear that a base diet of senescent temperate pasture that is low in digestible nutrients and low in nitrogen results in suppressed cashmere growth. Strategic grain supplementation for at least 9 weeks during late summer and autumn has the potential to significantly increase cashmere production and cashmere fibre length when adult cashmere goats are grazing pastures deficient in digestible energy and nitrogen. However feeding high levels of lupin and barley grain to adult goats is contra indicated as cashmere mean fibre diameter may exceed market limits. The practical application of the results is discussed in light of previous research.

Effects of melatonin implantation on cashmere growth, hormone concentrations and cashmere yield in cashmere-perennial-type Liaoning cashmere goats

2017 ◽  
Vol 57 (1) ◽  
pp. 60 ◽  
Author(s):  
Chunhui Duan ◽  
Jianhai Xu ◽  
Yu Zhang ◽  
Wei Zhang ◽  
Yabo Sun ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Growth Rate ◽  
Fibre Diameter ◽  
Control Group ◽  
Plasma Prolactin ◽  
Blood Samples ◽  
Growing Period ◽  
Plasma Melatonin ◽  
Cashmere Goats ◽  
Slow Growing

The aim of the present study was to investigate the effects of melatonin implants on cashmere growth, the concentrations of plasma melatonin and prolactin and the total cashmere yield in cashmere-perennial-type Liaoning cashmere goats. Twenty female goats were assigned to two treatments (n = 10) including a control and a treatment in which melatonin (2 mg/kg bodyweight) was implanted in March and May, respectively. The experiment lasted for 153 days. Fibre samples were collected in July, August and April the following year (before cashmere harvest). Blood samples were taken monthly from March to August. Cashmere yield was recorded after harvest. In melatonin-treated goats, cashmere length and cashmere growth rate from April to July were significantly increased (P < 0.05), but no influence was observed (P > 0.05) in August. Implantation of melatonin significantly increased plasma melatonin concentrations (P < 0.05) and decreased prolactin concentrations from April to July compared with the control group (P < 0.05), but no difference was observed in August (P > 0.05). Administration of melatonin increased the cashmere yield by 6.2% and the maximum cashmere length by 8.4%, but the differences were not significant (P > 0.05). Moreover, the cashmere fibre diameter was not influenced by melatonin implantation (P > 0.05). The results also indicated that plasma melatonin concentrations were correlated with plasma prolactin in the regulation of cashmere growth. Implantation of melatonin was an effective way to promote cashmere growth, and administration during the cashmere slow-growing period improved cashmere production without changing cashmere fibre diameter in cashmere-perennial-type Liaoning cashmere goats.

scholarly journals Analysis on Sustainable Development of Tire Industry Cluster Based on Life Cycle Theory

2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Xianghua Li ◽  
Peipei Liu ◽  
Zhaojun Wang
Keyword(s):  
Sustainable Development ◽  
Life Cycle ◽  
Development Process ◽  
Initial Period ◽  
Growth Period ◽  
Cycle Period ◽  
Industry Cluster ◽  
Tire Industry ◽  
Life Cycle Theory ◽  
Maturity Period

Abstract: The research on the tire industry cluster based on life cycle theory can be carried out by a four stages period namely as Initial Period, Growth Period, Maturity Period and Recession Period. This paper analyzes on the possible risks taken in each life cycle period as well as proposing corresponding suggestions to strengthens the research by looking into the conditions and factors of the continuous sustainable development process in a tire industry.

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