Efficiency of wool production of grazing sheep. 3. The use of sulphur-containing amino acids to stimulate wool growth

1970 ◽  
Vol 10 (47) ◽  
pp. 665 ◽  
Author(s):  
JP Langlands
Keyword(s):  
Amino Acids ◽  
Peritoneal Cavity ◽  
Sheep Grazing ◽  
Merino Sheep ◽  
Wool Production ◽  
Wool Growth ◽  
Grazing Sheep ◽  
Native Pastures

Merino sheep grazing native and improved pastures were given up to 2.2 g DL-methionine each day through an abomasal cannula. Wool growth of sheep grazing improved and native pastures was increased significantly by up to 30 and 41 per cent respectively. Nine sheep with abomasal camulae were maintained in pens, and were infused into the abomasum with 7 g DL-methionine per week given on either one, two, or seven days each week. Wool growth was significantly increased by daily infusions of DL-methionine but the response was less when the methionine was given on only one or two days each week. Dorset Horn wethers were given single injections of up to 50 g DL-methionine or L-cystine subcutaneously or into the peritoneal cavity. The rate of excretion of urinary sulphur was recorded following the injection. DL-methionine was rapidly excreted but L-cystine was excreted more slowly. In a series of trials quantities of DL-methionine, methionine hydroxy analogue (MHA) or L-cystine were injected subcutaneously or intra-peritoneally into grazing Merino sheep. DL-methionine did not increase wool growth and MHA was toxic. Twenty-eight g L-cystine given as two compressed pellets each month into the peritoneal cavity increased wool growth by approximately 22 per cent over the 8-week experim6ntal period.

Herbage intake and production of Merino sheep grazing native and improved pastures at different stocking rates

1974 ◽  
Vol 14 (68) ◽  
pp. 307 ◽  
Author(s):  
JP Langlands ◽  
JE Bowles
Keyword(s):  
Organic Matter ◽  
Nutritive Value ◽  
Sheep Grazing ◽  
Merino Sheep ◽  
Wool Production ◽  
Herbage Intake ◽  
Digestible Organic Matter ◽  
Native Pastures ◽  
Stocking Rates ◽  
Improved Pasture

Estimates were made of the herbage intake, nutritive value of the diet, liveweight, wool production, efficiency of wool production and fleece characteristics of fine wool merino sheep grazing native pastures at stocking rates of 1.9, 3.7 and 5.6 sheep ha-1. The effects of increased stocking rates on these variables, and differences between improved and native pastures were examined by regression analysis. Organic matter digestibility declined with increasing stocking rate and was consistently less on native than on improved pasture as were the N content and the ratio, N : organic matter digestibility in the diet. Organic matter intake/sheep did not differ between pasture types or stocking rates, but digestible organic matter, digestible nitrogen and nitrogen intakes were less on native pasture, and paralleled seasonal changes in nutritive value, minimum values being recorded in late winter. Both wool production/sheep and liveweight were greater on improved pastures. Wool production ha-1 was 4 to 10 times greater on improved than on native pastures at stocking rates at which wool production/sheep were similar. Efficiency of wool production expressed as g wool/100 g digestible organic matter consumed was greater on improved pasture but when expressed/100 g nitrogen intake, sheep grazing native pasture were more efficient. Possible reasons are discussed. The maintenance requirements for energy appeared to be similar on both types of pasture. Fleeces produced on native pastures were generally lighter with shorter staple lengths, and appeared to be one spinning count finer than those produced on improved pasture. They were also superior in terms of softness and colour but were less uniform.

scholarly journals Effects of Growth Hormone Administration on Wool Growth in Merino Sheep

1988 ◽  
Vol 41 (2) ◽  
pp. 177 ◽  
Author(s):  
PC Wynn ◽  
ALC Wallace ◽  
AC Kirby ◽  
EF Annison
Keyword(s):  
Amino Acids ◽  
Growth Hormone ◽  
Energy Intake ◽  
Nitrogen Balance ◽  
Daily Administration ◽  
Maintenance Energy ◽  
Merino Sheep ◽  
Growth Hormone Administration ◽  
Hormone Administration ◽  
Wool Growth

The effects of daily administration of 10 mg of highly purified ovine growth hormone (GH) for a period of 4 weeks on wool growth have been measured in 12 Merino ewes fed either a calculated maintenance energy intake or 1�6 times this amount (six on each ration). Concentrations of hormones, glucose, urea, a-amino N and amino acids in the blood were monitored and faeces and urine collected for measurement of nitrogen balance.

scholarly journals Effect of Sward Height on Rumen Degradation in Merino Grazing Sheep

1993 ◽  
Vol 1993 ◽  
pp. 180-180
Author(s):  
A.R. Mantecón ◽  
M.D. Carro ◽  
F.J. Giráldez ◽  
M.J. Ranilla ◽  
P.R. Revesado ◽  
...  
Keyword(s):  
Dry Matter ◽  
Rumen Fermentation ◽  
Sheep Grazing ◽  
Merino Sheep ◽  
Rumen Degradation ◽  
Sward Height ◽  
Grazing Sheep

It is now well established that the height of the sward grazed by sheep has a large effect on their performance (Hodgson, Mackie and Parker, 1986). However, there is a scarce of information about the rumen fermentation in sheep grazing at different sward heights. The aim of this experiment was to study the effect of sward height (4 vs 6 cm) on the rumen fermentation in Merino sheep which were continuously maintained on the pasture.The study was carried out on a continuously stocked pasture in August 1992. Twenty mature Merino sheep were used to obtain two different sward heights: 4 cm (low; LSH) and 6 cm (high; HSH). Sward height was measured twice weekly using a swardstick and was controlled by the addition and removal of sheep. Herbage mass was of 633 and 1397 kg of dry matter (DM)/Ha for the LSH and HSH paddocks, respectively.

Stimulation of wool growth by thyroxine implantation. I. Liveweight changes and wool growth of fine-wool Merino wethers

1964 ◽  
Vol 15 (4) ◽  
pp. 657 ◽  
Author(s):  
LJ Lambourne
Keyword(s):  
Dose Rate ◽  
Fibre Length ◽  
Dual Purpose ◽  
Wool Production ◽  
Wool Growth ◽  
Body Tissues ◽  
Four Seasons ◽  
Lower Body Weight ◽  
Native Pastures ◽  
Fleece Weight

Groups of 20 and 30 fine-wool Merino wethers were treated with L-thyroxine and their subsequent liveweight changes and wool production studied under a variety of grazing conditions for a year. Treatments comprised : (1) Single implantations of 60 mg in autumn, winter, spring, or summer. (2) Repeated implantations at all four seasons of 30, 60, or 90 mg. (3) Weekly subcutaneous injection of 7 mg in aqueous solution. These groups were grazed with untreated wethers on improved native pastures at one to two sheep per acre. (4) Repeated 60 mg implantations at four seasons in wethers grazed on native pasture providing a lower level of nutrition. (5) Repeated 60 mg implantations at four seasons in wethers grazed on sown pasture providing a higher level of nutrition. After every implantation there was a loss of 5–10 lb liveweight — more pronounced and more prolonged in the wethers given greater amounts of thyroxine, and more prolonged in those at lower levels of nutrition. Deaths occurred in several groups, increasing with dose rate or with poorer nutrition up to 30–50% of the group. Wool growth was not increased significantly by repeated 60 mg implants at the lowest level of nutrition, nor by the single 60 mg implant in late spring. Increases of 34% in annual fleece weight resulted from 60 mg implants in autumn and summer. Repeated implantation of 30, 60, and 90 mg in groups on a medium or high plane of nutrition increased annual fleece weight by 8, 14, and 19%, and 7 mg injected weekly by 11%. Increases in fleece weight were due partly to increased fibre length, and partly to an increase in grease and suint which reduced the clean scoured yield by 1–2%. It is concluded that line-wool Merinos, despite their lower body weight and greater specialization for wool production, react to thyroxine treatment in the same way as has been established for "dual-purpose" sheep. The safe maximum dose rate is critically dependent on the current level of nutrition, particularly for young sheep. Repeated implantations without adequate opportunity for recovery of catabolized body tissues may produce no increase in wool growth and may cause death.

Effects of defaunation of the rumen and supplementation with amino acids on the wool production of housed Saxon Merinos. 2. Methionine and protected methionine

1988 ◽  
Vol 28 (2) ◽  
pp. 179 ◽  
Author(s):  
DJ Cottle
Keyword(s):  
Amino Acids ◽  
Fibre Diameter ◽  
High Energy ◽  
Previous Trial ◽  
Growth Responses ◽  
Wool Production ◽  
Low Protein ◽  
Wool Growth ◽  
Protein Diets ◽  
Ciliate Protozoa

In experiment 1, 6 groups, each of 10 superfine Merino wethers, were individually penned indoors and hand-fed oats, wheat straw and whole lupins, either alone or with 2 g/day of DL-methionine or 6.6 g/day of fatty acid coated methionine (Ketionin) for 23 weeks. Following shearing the 6 groups were hand-fed lucerne-chopped hay in experiment 2 either alone or with hydroxymethyl-methionine (Mepron) or Ketionin for 23 weeks. In both experiments the rations were fed at maintenance level and were offered 3 times a week. Half of the sheep had no rumen ciliate protozoa following treatment in a previous trial. In experiment 1, defaunated sheep produced an additional 6.5%clean wool on the supplemented oats plus lupins rations. Inclusion of Ketionin in the ration of defaunated sheep resulted in an 11% increase in clean wool growth, without affecting wool quality. In experiment 2 defaunated sheep produced an additional 6% clean wool on the lucerne-chopped hay ration. No responses to defaunation occurred on the supplemented rations. Inclusion of both forms of protected methionine in the ration (providing 2 g methionine/sheep.day) resulted in 23% and 13% higher clean wool production in the faunated and defaunated sheep respectively. Fibre diameter of wool was increased by 0.7 pm in sheep receiving Mepron and 0-5 pm in sheep receiving Ketionin. The wool grown by suppiemented sheep remained suitable for the 'Sharlea' trade (< 17.5 �m). It is concluded that wool growth responds more to defaunation on high energy-low protein diets. Wool growth responses to supplementation with protected methionine were greater on 100% roughage diets than on high grain diets. Further study is needed before an optimal ration for superfine wool production is formulated.

A Comparative Study of Sheep Grazing a Semi-Arid Saltbush Pasture in Two Condition Classes.

1986 ◽  
Vol 8 (1) ◽  
pp. 46 ◽  
Author(s):  
RD Graetz
Keyword(s):  
Nutritional Value ◽  
Body Weight Gain ◽  
Landsat Imagery ◽  
Stocking Rate ◽  
Sheep Grazing ◽  
Wool Production ◽  
Broken Hill ◽  
Wool Growth ◽  
Stocking Rates

Measurements were made of the wool growth, body weight gain and diet of sheep grazing a saltbush pasture near Broken Hill, N.S.W. The experiment utilized a fenceline contrast in saltbush (Atriplex vesrcarra) density that was visible on Landsat imagery. It ran for five years (1976-1981) with a design of two pasture types by two stocking rates. Fleece weights varied from 3.9-6.0 kg/head and wool production from 0.6-2.9 kg/ha. Neither wool production per head nor bodyweight were substantially affected by stocking rate or pasture type. The composition and quality of the diets selected by sheep on both pastures were identical and of high nutritional value indicating their capability to accommodate differences in pasture composition. Pasture quality was not limiting between stocking rates or determined by the abundance of saltbush. Changes in pasture composition resulting from grazing and exclosure were small and of no significance.

Stimulation of wool growth by thyroxine implantation. II. Feed intake of grazing Merino wethers treated repeatedly with thyroxine.

1964 ◽  
Vol 15 (4) ◽  
pp. 676 ◽  
Author(s):  
LJ Lambourne
Keyword(s):  
Organic Matter ◽  
Feed Intake ◽  
Sheep Grazing ◽  
Wool Production ◽  
Wool Growth ◽  
Digestible Organic Matter ◽  
The Difference ◽  
Maintenance Requirements ◽  
Substantial Rise ◽  
Stimulation Of

Estimates have been made of the feed intake of wethers that received implantations of 60 mg thyroxine every 3 months, and of untreated sheep, grazing together. The estimated intake of digestible organic matter (D.O.M.) by treated wethers was higher than that of controls in 24 out of 27 measurement periods. The difference in feed intake was least in the iirst month after implantation, when the treated sheep lost weight, and greatest in the second and third months when the treated sheep were regaining weight. The overall increase in intake resulting from thyroxine treatment (20–25%) was greater than the increase in wool production (7% greasy weight, 3-7 % clean weight), and the efficiency of wool production was therefore lower in thyroxinetreated wethers. From the relationships between feed intake and rate of weight change it was concluded that in the month after implantation, when pulse rates indicated a substantial rise in metabolic rate, the maintenance feed requirement was raised from about 560 g to about 780 g D.O.M. per day. Observations in two winters with recently shorn sheep gave estimates of maintenance requirements for untreated wethers ranging from 850 to 1300 g D.O.M. per day. During recovery from repeated thyroxine implantation the wethers gained in weight no more efficiently than the controls. The mechanism of action of exogenous thyroxine is discussed in the light of these and other data.

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.

Efficiency of wool production of grazing sheep. 1. Differences between merino sheep selected for high and low fleece weight

1969 ◽  
Vol 9 (38) ◽  
pp. 249 ◽  
Author(s):  
BA Hamilton ◽  
JP Langlands
Keyword(s):  
Nitrogen Content ◽  
Merino Sheep ◽  
Wool Production ◽  
Grazing Sheep ◽  
Fleece Weight

The intake, wool production, and efficiency of wool production (wool production per unit intake) of rams drawn from two flocks selected for 13 years for high (Fleece Plus) and low (Fleece Minus) fleece weights were estimated while the rams grazed three pastures differing in the amount of herbage available. In a second experiment the rams were fistulated at the oesophagus and determinations were made of the digestibility and nitrogen content of the samples collected while the sheep grazed two pastures. The wool production, intake, and efficiency of the Fleece Plus rams were greater than those of the Fleece Minus on all pastures. Variability in wool production was primarily attributable to variability in efficiency. Differences between flocks in wool production and efficiency increased when herbage availability and wool production were high.

The patterns of wool growth of Merino sheep grazing three Chenopod shrub rangelands.

1980 ◽  
Vol 2 (1) ◽  
pp. 53 ◽  
Author(s):  
RD Graetz
Keyword(s):  
Seasonal Variations ◽  
Experimental Period ◽  
Stocking Rate ◽  
Sheep Grazing ◽  
The West ◽  
Merino Sheep ◽  
Management Regime ◽  
Wool Growth ◽  
South Wales ◽  
Different Types

Annual fleece we~ghts and the seasonal varldtlon m uool growth of Peppm Merino wethers were measured for nearlv tlve years on three paddocks on the pastoral property 'Pme Creek' in the West Darlnlg distr~ct of Nea South Wales. The paddocks had the same stocking rate but encloyed different types of shrub rangelands - saltbush, pearl bluebush and degraded bluebush. Annual fleece weights varied between 4.0 and 5.3 kg (clean scoured) per sheep with no significant differences between the flocks in the different paddocks in any year. There were only small differences within years in the seasonal variations in wool growth for sheep from the three paddocks. Analysis of the relationships between ramfall and fleece weights during the experimental period and from 18 years of property records revealed that under the conservative stocking management regime of this property, wool cut per head \%as largely independent of the previous year's ramfali.

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