The influence of high ambient temperatures and plane of nutrition on wool growth rates of tropical sheep

1975 ◽  
Vol 15 (77) ◽  
pp. 753 ◽  
Author(s):  
KW Entwistle
Keyword(s):  
Heat Treatment ◽  
Treatment Period ◽  
Growth Rates ◽  
Temperature Treatment ◽  
Wool Production ◽  
Ambient Temperatures ◽  
Treatment Groups ◽  
Wool Growth ◽  
Temperature Regimen ◽  
Quality Diet

The wool production of two groups of tropical Merino sheep subjected to a simulated summer circadian temperature regimen, and fed either high or low quality diets, was compared with that of two other groups under similar nutritional conditions but held at prevailing winter ambient temperatures. The nutritional treatments were imposed for the duration of the experiment; the temperature treatments consisted of a. pre-experimental period of three weeks in which all groups were held at prevailing ambient temperatures b. heat adaptation period of one week in which the heat treatment groups were subjected to gradual increases in the circadian temperature regimen c. heat treatment period of three weeks in which the heat treatment groups were exposed to a circadian temperature regimen in which air temperatures were in excess of 38�C for approximately 7 hours day-1d. post heat treatment period of three weeks in which all groups were held at prevailing ambient temperatures. Temperature treatment had no effect on feed intake or liveweight gain; however, intakes progressively decreased in groups on the low quality diet with a similar decrease in liveweight. Wool growth rates were unaffected by temperature treatment, but were significantly lower in animals on the low quality diet. The possible significance of these results to the wool production of tropical sheep is discussed.

Effect of abomasal infusions of methionine, casein, and starch plus methionine on the wool production of Merino wethers fed on lucerne or wheaten chaff

1974 ◽  
Vol 25 (6) ◽  
pp. 945 ◽  
Author(s):  
H Dove ◽  
GE Robards
Keyword(s):  
Body Weight ◽  
Body Weight Gain ◽  
Nitrogen Retention ◽  
Basal Diet ◽  
Nitrogen Excretion ◽  
Wool Production ◽  
Wool Growth ◽  
Quality Diet ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen

Merino wethers received daily abomasal infusions of (a) 2.6 g DL-methionine, (b) 80 g casein protein or (c) 2.6 g DL-methionine plus 87 g maize starch, while consuming either lucerne chaff or wheaten chaff. Responses in wool growth, nitrogen metabolism and body weight were measured. Sheep fed on lucerne chaff had a higher urinary nitrogen excretion and nitrogen retention than those fed on wheaten chaff regardless of the presence or type of infusion. The infusion of methionine did not markedly alter these parameters from their original levels on either diet. On both diets, casein infusion led to increased urinary nitrogen excretion and nitrogen retention. Compared with sheep given starch plus methionine infusions, those given casein had higher urinary nitrogen excretion and nitrogen retention. Changes in fleece-free body weight gain followed a similar pattern. There were no pronounced differences in faecal nitrogen excretion. Regardless of the presence or type of infusion, sheep fed on lucerne grew more wool than those on wheaten chaff. On both diets, all infusions were accompanied by higher wool growths than on the basal diet alone. The effect of the casein infusion, compared with methionine infusion, was apparent only in sheep on wheaten chaff. Wool growth rates in sheep infused with starch plus methionine were not higher than the rates in the same sheep infused with methionine alone. The results suggest that the wool production of sheep will show a greater response to abomasal supplements of sulphur amino acids or casein if they are consuming a high quality diet such as lucerne chaff, compared with a low quality diet such as wheaten chaff. The apparent failure of starch infusion to stimulate wool growth above the level obtained with methionine infusions alone is discussed in relation to the interaction of protein and energy in the growth of wool.

Effects of defaunation of the rumen and supplementation with amino acids on the wool production of housed Saxon Merinos. 1. Lupins and extruded lupins

1988 ◽  
Vol 28 (2) ◽  
pp. 173 ◽  
Author(s):  
DJ Cottle
Keyword(s):  
Amino Acids ◽  
Wheat Straw ◽  
Sulfur Content ◽  
Growth Rates ◽  
Trial Period ◽  
Wool Production ◽  
Lower Resistance ◽  
Wool Growth ◽  
Wool Quality

Six groups, each comprising 10 superfine Merino wethers ('Sharlea'), were individually penned indoors and hand-fed oats and wheat straw, either alone or with 10% (w/w) crushed lupins or extruded lupins. The rations were fed at maintenance level and were offered 3 times a week. Half of the sheep were defaunated by drenching with Alkanate 3SL3. Wool growth rates and wool quality were measured during a 5-month trial period. Defaunation resulted in a 6.5% increase in clean wool production, with a 3% higher sulfur content. The quality of the wool grown was unaffected by defaunation. Inclusion of lupins or extruded lupins in the ration resulted in a 10% increase in clean wool growth. Wool quality was largely unaffected, though a lower resistance to compression was apparent. It was concluded that a reasonable diet for 'Sharlea' production was 500g oats, 50g wheat straw, 50g lupins, 10.5g vitamin, mineral mix per sheep per day. This diet may be further improved by additional ingredients and defaunation of the sheep.

Effects of nutrition and paring on linear hoof growth in sheep

1990 ◽  
Vol 41 (1) ◽  
pp. 197
Author(s):  
JL Wheeler ◽  
HI Davies ◽  
DA Hedges ◽  
PJ Reis
Keyword(s):  
Growth Rate ◽  
Ambient Temperature ◽  
Direct Effect ◽  
Growth Rates ◽  
Dry Matter ◽  
Latin Square ◽  
Residual Effects ◽  
Wool Production ◽  
Wool Growth ◽  
Nutritional Changes

Paring increased the linear hoof growth on the forefeet of Merino wethers by an average of 4.1% (P < 0.05) with a tendency for paring to promote faster growth on the medial digits. Effects of feeding these sheep with 400, 600, or 1000 g pelleted ration day-1 were assessed in a 4 X 4 Latin square design with 28-day periods using four measures of response. An extra (fifth) period was used to determine residual effects. The proportion of residual (carryover) to direct effect was much smaller for hoof growth than for wool. Hoof growth was not related to wool production. In another experiment, hoof growth rate of sheep increased from 103 to 136 8m day-1 when the intake of digestible dry matter was increased from 400 to 600 g day-1 (P< 0.001), and from 115 to 125 8m day -1 (P> 0.05) when the intake of digestible nitrogen was increased from 12 to 25 g day-1. Hoof growth rates of Merino wethers grazing native or sown pasture were not significantly affected by injecting DL-methionine daily into the abomasum. Hoof growth is not an appropriate index of wool growth. It may provide an easily measured, rapidly responsive and cumulative measure of nutritional changes, but its use cannot be recommended until more information is available on the factors that affect it and their interaction with ambient temperature.

Responses to feeding canola meal or lupin seed to pregnant, lactating, and dry ewes

1996 ◽  
Vol 47 (8) ◽  
pp. 1291 ◽  
Author(s):  
DG Masters ◽  
G Mata
Keyword(s):  
Birth Weight ◽  
Treatment Period ◽  
Fibre Diameter ◽  
Canola Meal ◽  
Wool Production ◽  
Rumen Degradation ◽  
Wool Growth ◽  
Lupin Seed ◽  
Average Fibre

Responses in wool production, ewe liveweight, lamb birth weight, and growth were compared when the major source of protein in the diet was either lupin seed or canola meal. The diets were fed to ewes during the final 3 weeks of pregnancy and first 3 weeks of lactation, and for a similar period of time to a group of dry ewes. All ewes were fed to maintain conceptus-free liveweight. The diet containing canola meal increased (P < 0.001) wool growth in the reproducing ewes (50-63%) and the dry ewes (12.5-20%) during, and for 3 weeks after, the treatment period. Fibre diameter of wool grown during the treatment period was increased (P < 0.025) by 0.5-1.5 pm in the ewes fed canola meal compared with ewes fed lupins. The ewes fed canola meal gained slightly (P = 0.06) more weight during the experiment than the ewes fed lupins. Lambs from the ewes fed canola meal were lighter (P < 0.05) at birth (480 g) than lambs from ewes fed lupins. The reproducing ewes had lower fleece weights, average fibre diameters, and staple strengths and lengths than the dry ewes. These fleece characteristics were not significantly affected by diet. Canola meal is partially protected from rumen degradation and is less expensive than other sources of similar proteins and may therefore provide a practical option for commercial sheep producers.

Intake and long-term cysteine supplementation change wool characteristics of Romney sheep

2001 ◽  
Vol 52 (1) ◽  
pp. 29 ◽  
Author(s):  
R. G. Sherlock ◽  
P. M. Harris ◽  
J. Lee ◽  
G. A. Wickham ◽  
J. L. Woods ◽  
...  
Keyword(s):  
Growth Rate ◽  
Treatment Period ◽  
Fibre Diameter ◽  
Wool Fibre ◽  
Amino Acid Supplementation ◽  
Sulfur Concentration ◽  
Treatment Groups ◽  
Length Growth ◽  
Wool Growth ◽  
Pre Treatment

Sulfur amino acid supplementation increases wool production in sheep at low planes of nutrition but it is unclear whether there is any benefit of supplementation at planes of nutrition above maintenance and what implications this might have for wool quality characteristics. This experiment directly investigated the interaction between sulfur supplementation and plane of nutrition in terms of wool growth and fibre characteristics. Twenty-four Romney ewes, acclimatised in individual metabolism units over a 7-week pre-treatment period, were allocated to 1 of 4 treatment groups based on a 22 factorial arrangement. Groups were low (L) or high (H) intake (0.8 or 1.3 maintenance, respectively) with continuous intravenous infusion of either saline (–Cys) or cysteine (+Cys, 2 g/day). During the 3-month treatment period, measurements were obtained for liveweight, plasma cysteine concentration, wool sulfur concentration and output, clean wool growth, mean fibre diameter (MFD), length growth rate (LGR), colour, loose wool bulk, handle, and crimp frequency and character. Clean wool growth response (P < 0.05) to cysteine supplementation was greater for the L sheep (6.06 v. 4.31 g/100 cm2) than the H sheep (7.20 v. 6.13 g/100 cm2). The response to supplementation in LGR (P < 0.01) was similar in both H (14%) and L (20%) sheep. There was no response in MFD due to sulfur supplementation, although fibre diameter measurements made along the fibres suggest that there was a response in L but not H sheep (P < 0.1). Wool sulfur concentration and output increased as a result of cysteine supplementation but concentration increased more in L (30.6 v. 24.5 mg S/g; P < 0.01) than in H sheep (28.4 v. 26.2 mg S/g). Qualitative electrophoresis analyses suggested that the increase in wool sulfur was achieved primarily by an increase in ultra-high-sulfur proteins. Crimp frequency and character were both significantly (P < 0.01) enhanced by cysteine supplementation. It is concluded that cysteine supplementation, at feed intakes that commonly occur in the commercial situation, can produce a useful increase in wool growth. This growth increase is primarily accomplished by increasing length growth rate rather than fibre diameter, which should also improve the value of the wool fibre produced.

Supplementary feeding pattern and rate of liveweight gain in winter-spring affect wool production of young Merino sheep on the south coast of Western Australia

1995 ◽  
Vol 35 (8) ◽  
pp. 1093 ◽  
Author(s):  
PT Doyle ◽  
TW Plaisted ◽  
RA Love
Keyword(s):  
Growth Rates ◽  
Management Strategies ◽  
Fibre Diameter ◽  
Supplementary Feeding ◽  
Stocking Rate ◽  
Merino Sheep ◽  
Wool Production ◽  
Wool Growth ◽  
Staple Strength ◽  
Stocking Rates

The effects of different supplementary feeding practices in summer-autumn and management strategies on green pasture on liveweight change, wool growth rate, annual wool production and wool characteristics of young Merino wethers were examined at 2 farms. The grain feeding treatments were lupins (L) or lupins and oats (LO) fed in amounts that were adjusted to try and maintain liveweight, or lupins and oats (LOG) fed at a higher rate. The objectives of liveweight maintenance or gain were not always achieved, but liveweight patterns differed between LOG compared with L or LO during summer-autumn. The sheep used at farm 1 were aged 4.5 months and liveweight 32 kg at the start of the experiment, while those at farm 2 were 6.5 months and liveweight 39 kg. The stocking rate in summer-autumn was 8 wethers/ha at both farms. During supplementation, sheep on LOG had a higher (P<0.05) liveweight change compared with those on L or LO (farm 1, 15 v. -8 g/sheep. day; farm 2, -35 v. -51 g/sheep. day) and clean wool growth rates (farm 1, 7.1 v. 6.4 g/sheep. day; farm 2, 5.1 v. 4.8 g/sheep.day). The sheep on LOG grew broader (P<0.05) wool than those on L or LO (farm 1, 19.0 v. 18.5 �m; farm 2, 21.7 v. 20.8 �m), and at farm 1 length was also greater (P<0.05) (114 v. 111 mm), while at farm 2 staple strength was greater (P<0.01) (22.9 v. 16.4 N/ktex). There were no significant differences in annual clean wool production. There were positive (P<0.01) relationships between staple strength and liveweight change to the time of minimum liveweight in summer-autumn. After green pasture on offer reached 500 kg DM/ha in autumn, different liveweight change patterns were achieved in 2 groups (LS, lower stocking rates; HS, higher stocking rates) of sheep at each farm by adjusting stocking rates. Within a farm, the LS and HS groups were comprised of equal numbers of sheep from each replicate of the supplementary feeding treatments. There were differences (P<0.05 to 0.01) in liveweight change between LS and HS (farm 1, 93 v. 72 g/day; farm 2, 127 v. 60 g/day), the differences being more pronounced at farm 2. The differential stocking rates at farm 2 resulted in differences in clean wool growth rates (P<0.01), in clean wool production (4.22 v. 4.53 kg, P<0.05), and fibre diameter (20.8 v. 21.4 �m, P<0.01), but there were no significant effects on staple length or strength. There were no significant effects of the supplementary feeding treatments imposed in summer-autumn on the responses to the stocking rate treatments on green pasture.

Effect of heat and its timing within a polyhouse on flowering in potted Douglas-fir trees

1992 ◽  
Vol 22 (5) ◽  
pp. 736-739 ◽  
Author(s):  
Stephen D. Ross
Keyword(s):  
Heat Treatment ◽  
Low Temperatures ◽  
Shoot Elongation ◽  
Douglas Fir ◽  
Naphthaleneacetic Acid ◽  
Bud Burst ◽  
Rooted Cuttings ◽  
Ambient Temperatures ◽  
Temperature Regimen ◽  
Vegetative Bud

Female and male flowering in potted Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) rooted cuttings treated with gibberellin A4/7, with and without naphthaleneacetic acid, were inhibited by heat treatment in a closed polyhouse with a temperature regimen of 28:15 °C (day:night) relative to the flowering achieved in an open-sided polyhouse with near-ambient temperatures. The effect was greater for an early heat treatment (from vegetative bud burst to end of shoot elongation), which bracketed cone-bud differentiation, than for a following late heat treatment of similar duration. Effects of the early plus late heat treatments were additive. It was not the objective of this study to determine the optimal temperature regimen for flowering. However, other than possibly in locations where low temperatures prevail during cone-bud differentiation in spring, heat treatment within a polyhouse appears to be neither a necessary nor desirable adjunct to gibberellin A4/7 for promotion of flowering in potted Douglas-fir.

Mineral supplementation and wool production of young Merino sheep on the south coast of Western Australia

1995 ◽  
Vol 35 (4) ◽  
pp. 437
Author(s):  
PT Doyle ◽  
RA Love ◽  
TW Plaisted
Keyword(s):  
Growth Rates ◽  
Fibre Diameter ◽  
Supplementary Feeding ◽  
Wool Production ◽  
Average Fibre Diameter ◽  
Mineral Supplementation ◽  
Wool Growth ◽  
Average Fibre ◽  
Staple Strength ◽  
Mineral Lick

Wool-free liveweight change (LWC), wool growth rate, annual wool production, and wool characteristics of young Merino wethers fed supplements of lupins with gypsum or a multi-element mineral lick were examined in 12 experiments at 5 farms between 1989 and 1992. The source of sheep varied between experiments; age was 4.5-6.5 months and liveweight 28-37 kg at the beginning of supplementation. Sheep were fed lupins, lupins coated with gypsum (15-20 g/kg lupins), or lupins along with access to the mineral lick (offered at 140 g/sheep.week). The amount of lupins offered in all treatments within any experiment was the same. Supplementary feeding varied between experiments from 150 to 240 days. The sheep grazed annual pastures at stocking rates of 8-1 6.7ha. Average lick intake was 12-18 g/sheep. day. During supplementary feeding, there was considerable variation in LWC (-80 to +110 g/day) and clean wool growth rates (3.8-15.1 g/day) within and between experiments. However, there was no significant positive effect of gypsum or mineral lick supplementation on LWC or clean wool growth rates during or after supplementary feeding in any experiment. There were positive (P<0.01) relationships between LWC and clean wool growth rates during supplementation. Also, for some spring-shorn sheep types, staple strength of wool was linearly related (P<0.01) to LWC in the period before the position of break in the wool staple. Annual wool production, average fibre diameter, and staple strength of midside wool were not significantly increased by supplements of gypsum or mineral lick in any experiment.

APPLICATION OF ESR TO HIGH-Tc SUPERCONDUCTORS AND RELATED MATERIALS II: ESR of Cu2+ AS A PROBE OF CRYSTAL GROWTH RATES OF Y2BaCuO5 IN THE MELTS OF Y1.8Ba2.4Cu3.4Ox

1999 ◽  
Vol 13 (02) ◽  
pp. 43-50
Author(s):  
K. YAMAMOTO ◽  
S. KAWASHIMA ◽  
K. HOTTA ◽  
K. SUGAWARA ◽  
H. HIROSE
Keyword(s):  
Heat Treatment ◽  
Crystal Growth ◽  
Treatment Period ◽  
Growth Rates ◽  
Heat Treatment Temperature ◽  
Treatment Temperature ◽  
Nominal Composition ◽  
High Tc Superconductors ◽  
High Tc

The effects of heat-treatment temperature (HTT) and heat-treatment period (HTP) on the growth rates of Y 2 BaCuO 5 in the melts with nominal composition of Y: Ba : Cu = 1.8 : 2.4 : 3.4 have been investigated. The ranges of HTT and HTP are 1000~1400° C and 1~120 minutes, respectively. The quantities of Cu 2+ in Y 2 BaCuO 5 have been obtained by ESR, and its growth rates in the aforementioned melts have been quantitatively measured as functions of HTT and HTP.

The effect of stocking rate and deferred Autumn grazing of pasture on liveweight and wool production of Merino wethers in a Mediterranean-type climate

1976 ◽  
Vol 16 (79) ◽  
pp. 189 ◽  
Author(s):  
TH Brown
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
South Australia ◽  
Management Systems ◽  
Research Centre ◽  
Stocking Rate ◽  
Wool Production ◽  
Wool Growth ◽  
The Cost ◽  
Stocking Rates

Liveweight, seasonal wool growth rates, annual wool production, wool quality and hand feeding requirements were recorded for Merino wethers when autumn deferred or continuously grazed. The two management systems were compared at a series of eight stocking rates from 12.4 to 29.7 sheep per hectare for five years from 1967 to 1971 at the Kybybolite Research Centre, South Australia. Autumn deferment resulted in increased liveweight and wool growth rate during the months of June to September. However, liveweights and wool production under either management were similar for the remainder of the year. Because deferred grazing did not increase liveweights during the critical autumn period, and since hand feeding requirements were similar under either management system at the higher stocking rates, it is suggested that yearly stocking rates can not be increased by autumn deferment. Apart from the drought year of 1967, the continuously grazed sheep required little or no hand feeding up to 22.2 wethers per hectare. It is unlikely that the cost of hand feeding deferred sheep up to this stocking rate would be covered by the small increase in wool production. However, this would depend on the cost of conserved fodder and price received for the wool.

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