Effects of differential grazing of annual pastures in spring and age of sheep on pasture and sheep production

1997 ◽  
Vol 37 (7) ◽  
pp. 727 ◽  
Author(s):  
A. N. Thompson ◽  
M. W. Hyder ◽  
P. T. Doyle
Keyword(s):  
Growth Rate ◽  
Dry Matter ◽  
Fibre Diameter ◽  
Wool Growth ◽  
Period 2 ◽  
Significant Difference ◽  
Condition Score ◽  
Staple Strength ◽  
Sheep Production ◽  
Curvilinear Relationships

Summary. The effects of controlled grazing through spring on the production of young (age 1 year; liveweight 38.3 ± 0.09 kg; condition score 3.0 ± 0.03) and mature (age 3 years; liveweight 61.9 ± 0.36 kg; condition score 3.1 ± 0.04) Merino wethers was examined. The grazing treatments involved adjusting sheep numbers to maintain green feed on offer near target amounts of 800, 1200, 1600, 2000, 2400 and 2800 kg dry matter/ha. Liveweight and wool growth measurements were made on 8 sheep per plot, with additional animals added or removed as necessary to maintain pasture near the target feed on offer. Changes in wool-free liveweight were linear between days 0 and 42 (period 1), and days 42 and 111 (period 2) for both classes of sheep grazing low feed on offer treatments. Hoggets lost less liveweight than mature animals while grazing low feed on offer during period 1 and gained liveweight faster (P<0.05) than mature animals for any feed on offer during period 2. Curvilinear relationships existed between feed on offer and clean wool growth rate and fibre diameter, with feed on offer accounting for 65 and 81% of the variations in wool growth rate, and 65 and 73% of the variations in fibre diameter, for hogget and mature sheep respectively. There was no significant difference in wool growth rate between animal classes. Annual clean wool production, fibre diameter and staple length increased linearly (P<0.05) with increasing feed on offer. Staple strength was higher (P<0.05) in mature sheep compared with hoggets, but was greater than 30 N/ktex for both classes of sheep irrespective of feed on offer. These results indicate that intensive grazing in spring to predetermined feed on offer is a useful tactic for manipulation of wool growth and fibre diameter, but factors other than feed on offer also contribute to liveweight change and wool growth.

Strip grazing to control wool growth rate of sheep grazing green annual pastures

1999 ◽  
Vol 39 (3) ◽  
pp. 247 ◽  
Author(s):  
J. Young ◽  
P. T. Doyle ◽  
P. Booth
Keyword(s):  
Growth Rate ◽  
Production Systems ◽  
Fibre Diameter ◽  
Matter Content ◽  
Stocking Rate ◽  
Merino Sheep ◽  
Wool Growth ◽  
Staple Strength ◽  
Sheep Production ◽  
Strip Grazing

We compared strip grazing (SG) as a means of controlling wool growth rate, reducing variation in fibre diameter along the staple, and of carrying more Merino sheep through winter on green annual pastures, with set stocking (SS) in 3 experiments. In experiments 1 and 2, SG involved grazing to a residual feed on offer (FOO) of 400 kg DM/ha with an estimated intake of about 0.8 kg DM/day for each sheep. Treatments commenced after pasture establishment in autumn–winter, with both treatments stocked at 20 wethers/ha until late spring. During spring, average liveweight changes were lower (P<0.01) under SG than SS (55 v. 153 g/day experiment 1; –16 v. 217 g/day experiment 2). Strip grazing, compared with SS, reduced (P<0.01) the variation in wool growth rate and fibre diameter along the staple leading to lower (P<0.01) clean wool weights (3.54 v. 3.94 and 2.97 v. 4.12 kg), but finer (P<0.01) (20.9 v. 22.0 and 19.5 v. 21.5 mm), stronger (P<0.01) (28.6 v. 25.3 and 39.9 v. 35.5 N/ktex) wool. However, there was also an increase in vegetable matter content of the wool. The effects on annual pastures were to increase grass (79 v. 48 and 59 v. 25%) and reduce legume (12 v. 36 and 22 v. 54%) content at the end of spring. In experiment 3, two strip grazing treatments were used: SGl with a residual FOO of about 400 kg DM/ha and a stocking rate of 28 wethers/ha; and SGh with a residual FOO of about 800 kg DM/ha and stocking rate of 14 wethers/ha. The stocking rate for SS was 12 wethers/ha. SGl, following an autumn deferment, enabled a stocking rate of 28 wethers/ha to be sustained through winter without supplementary feeding. This is substantially higher than the district average stocking rate of about 7 sheep/ha. Strip grazing reduced (P<0.01) liveweights at the completion of treatments (SGl 41.9 v. SGh 47.9 v. SS 60.3 kg), reduced (P<0.01) clean wool weights (3.40 v. 3.72 v. 4.54 kg) and mean fibre diameter (19.1 v. 19.0 v. 20.9 m), but increased staple strength (21.3 v. 19.0 v. 16.9 N/ktex). These results are discussed in relation to opportunities to utilise strip grazing in sheep production systems on annual pastures in south-western Australia.

Fibre diameter and staple strength of sheep selected for divergent clean fleece weight when subjected to an increase in intake or an increase in intake and diet change

2005 ◽  
Vol 56 (2) ◽  
pp. 195 ◽  
Author(s):  
M. A. Friend ◽  
G. E. Robards
Keyword(s):  
Growth Rate ◽  
Stepwise Regression ◽  
Fibre Diameter ◽  
Dietary Treatment ◽  
Diet Change ◽  
Wool Growth ◽  
Ad Libitum ◽  
Staple Strength ◽  
Fleece Weight ◽  
Ad Libitum Feeding

Merino wethers with a high (fleece plus, Fl+) or low (fleece minus, Fl–) potential for wool growth were offered a restricted intake of either oat grain or lucerne chaff for 8 weeks followed by ad libitum lucerne chaff for 4 weeks. The Fl– sheep that were fed oats then lucerne had a lower (P < 0.05) intake during the first 2 weeks of ad libitum feeding than all other groups. Staple strength of Fl+ sheep (37.5 ± 2.2 N/ktex) was less (P < 0.05) than that of Fl– sheep (44.5 ± 2.4 N/ktex), and dietary treatment did not significantly affect staple strength. Wool growth rate was unaffected by dietary treatment, but was greater (P < 0.001) for Fl+ (6.4 ± 0.2 µg/mm2.day) than for Fl– (4.0 ± 0.2 µg/mm2.day) sheep. Along-fibre variation in diameter was greater (P < 0.001) in Fl+ (15.6 ± 0.5%) than in Fl– (9.9 ± 0.5%) sheep. Between-fibre variation in diameter was greater (P < 0.001) in Fl+ (16.5 ± 0.5%) than in Fl– (13.2 ± 0.5%) sheep, and between-fibre variation in diameter was affected (P < 0.05) by dietary treatment in Fl+ sheep. Staple strength was significantly correlated (P < 0.05) with along-fibre variation in diameter (r = –0.48), and stepwise regression analysis indicated that along-fibre variation in diameter, wool growth rate during early restricted feeding, and minimum fibre diameter explained 63% of the variance in staple strength. The results are discussed in relation to the lower staple strength of Fl+ sheep.

Effect of selection for wool growth on seasonal patterns of yield, fibre diameter, and colour in Romney lines

1995 ◽  
Vol 35 (1) ◽  
pp. 27 ◽  
Author(s):  
T Wuliji ◽  
IL Weatherall ◽  
RN Andrews ◽  
KG Dodds ◽  
PR Turner ◽  
...  
Keyword(s):  
Growth Rate ◽  
Fibre Diameter ◽  
Seasonal Patterns ◽  
Control Line ◽  
Wool Growth ◽  
Growth Decline ◽  
Selection For ◽  
Staple Strength ◽  
Fleece Weight

Seasonal wool growth and associated wool characteristics were measured in a Romney line selected for high fleece weight and an unselected control line in 1990 and 1991. Both had a significant (P<0.01) decline in wool growth rate in winter compared with summer. The wool growth rate advantage (P<0.001) of the selected line over the control averaged 19 and 33% for ewes, and 24 and 36% for hoggets, in summer and winter, respectively. Staple strength, yield, and fibre diameter differences were closely associated with wool growth. Colour analysis showed no difference between lines in either brightness (Y) or yellowness (Y - Z). However, both the Y and Z values were lower in spring and summer, while Y - Z was highest in summer. The results suggest that selection for high fleece weight also improves major wool characteristics and reduces the relative winter wool growth decline in Romneys.

scholarly journals The effect of different pasture management strategies in north-west Queensland on liveweight gain and wool growth rate of several groups of young sheep.

1985 ◽  
Vol 7 (2) ◽  
pp. 75 ◽  
Author(s):  
RGA Stephenson ◽  
DA Pritchard ◽  
PM Pepper ◽  
PT Connelly
Keyword(s):  
Growth Rate ◽  
Dry Matter ◽  
Management Strategies ◽  
Live Weight ◽  
Dry Season ◽  
Wet Season ◽  
Pasture Management ◽  
North West ◽  
Wool Growth ◽  
Significant Difference

The effect of three different pasture management strategies on liveweight gain and wool growth rate of young(weaner) sheep was examined immediately after weaning on Mitchell grass-Flinders grass pastures during the dry season of north-west Queensland. The pasture management strategies were designed to mimic various industry situations, while the performance of four different progeny groups was compared and used to provide an overall assessment of pasture quality. Pasture treatments (experiment 1) consisted of three paddocks, a harvested (c. 8% of pasture harvested and baled) and spelled, a spelled, and a continuously grazed paddock. Spelled paddocks were not grazed during and after the wet season for a period of six months while the continuously grazed paddock was continuously stocked before the experiment. Experiment 2 consisted of spelled and continuously grazed paddocks. Pastures were evaluated by measuring the changes in composition and quality (experiment 1) and the responses in liveweight gain (experiments 1 and 2) and wool growth of the weaners (experiment 1). Marked improvements (c. 100%) in weaner growth rates occurred in the spelled paddocks. Greasy wool production by three groups of ewes in experiment I was about 14% greater in the harvested paddock than in the others. At the start of the trial there were no significant differences in dry matter yield but a significant difference in botanical composition occurred between paddocks. The changes in dry matter that occurred between the beginning and end of grazing were not significantly different between paddocks. Before gazing, forbs made up approximately 16%, 4% and 1% of pastures in harvested, spelled and continuously grazed paddocks respectively. The change in the percentage forbs that occurred between the beginning and end of the grazing period was significantly greater in the harvested paddock than in the other paddocks indicating preferential selection and intake by sheep. The differences in weaner live weight and wool growth between paddocks suggest that paddock management can improve weaner productivity. The study also indicates that paddock management could be successfully used to increase the percentage of forbs and quality of the pasture during the dry season. The superior wool growth of two progeny groups also suggests that improved productivity of breeding flocks in the tropics is possible if superior sheep can be identified. The results highlight the importance of preferential management of pasture for weaners so that productivity advantages can be exploited.

Sulfur supplementation of lupin grain diets fed to young sheep

1999 ◽  
Vol 39 (6) ◽  
pp. 657
Author(s):  
P. T. Doyle ◽  
A. J. M. Ritchie ◽  
M. R. Ellis
Keyword(s):  
Growth Rate ◽  
Dry Matter ◽  
Fibre Diameter ◽  
Sulfur Amino Acid ◽  
Cereal Straw ◽  
Dry Matter Digestibility ◽  
Wool Growth ◽  
Limiting Nutrients ◽  
Metabolisable Energy ◽  
Maintenance Requirements

Summary. We examined the effects of supplementation of lupins with limestone or gypsum on liveweight change and wool production of young Merino wethers [age 10 months; starting liveweight (mean s.e.m.) 34.8 0.33 kg]. Lupins with the added compounds were fed in amounts estimated to provide metabolisable energy at 0.8, 1.0, 1.5 and 2.0 times maintenance requirements. The remainder of the ration was cereal straw fed at 10% of the weight of lupins given. Lupins coated with limestone or gypsum had a dry matter digestibility of 880 g/kg, and contained (g/kg DM) nitrogen 56.1 v. 57.4, sulfur 2.3 v. 4.6 and calcium 7.9 v. 5.4 respectively. As the amount of the ration fed was increased, there were linear increases (P<0.001) in liveweight gain (–9 to 226 g/day), clean wool growth rate (5.3–10.2 g/day), and fibre diameter of wool grown (18.0–21.6 m). There were no significant differences between lupins coated with limestone or gypsum in liveweight change (97 v. 105 g/day) or clean wool growth rate (7.6 v. 7.5 g/day). While the addition of sulfur to the diet reduced fibre diameter of wool grown (19.4 v. 20.0 m; P<0.01), this is not consistent with the effects of increased sulfur amino acid supply which would be expected to increase fibre diameter. It is concluded that the supply of inorganic sulfur to ruminal organisms was not limiting production responses to lupins or that there were other more limiting nutrients.

Effects of stocking rate in spring on liveweight and wool production of sheep grazing annual pastures

1994 ◽  
Vol 45 (2) ◽  
pp. 367 ◽  
Author(s):  
AN Thompson ◽  
PT Doyle ◽  
M Grimm
Keyword(s):  
Fibre Diameter ◽  
Stocking Rate ◽  
Wool Production ◽  
Wool Growth ◽  
Linear Relationships ◽  
Condition Score ◽  
Grazing Period ◽  
Staple Strength ◽  
Stocking Rates ◽  
Staple Length

Two experiments examined the effects of different stocking rates in spring, and hence the availability of annual pastures, on changes in liveweight and wool production in Merino wethers (Experiments 1 and 2 respectively: age 5 and 2+-year-old; liveweight 63.8 � 0.64 (s.e.m.) kg and 43.8 � 0.34 kg; condition score 3.9% 0.14 and 3.l � 0-08). In Experiment 1, stocking rates were 8, 16, 24, 32 and 40 sheep/ha from 8 August, 1989 f9r 122 days; Experiment 2 involved an additional stocking rate of 48 sheep/ha from 23 August, 1990 for 98 days. Feed on offer (FOO kg DM/ha) declined (P < 0.01) linearly as stocking rate increased. Stocking rate and initial FOO (ranging between 1100 and 7000 kg DM/ha) had no significant effects on pasture growth rate (PGR) through most of spring. Late in spring, increased stocking rates resulted in greater (P < 0.05) PGR. The total amount of pasture produced in the grazing period was not significantly affected by stocking rate (Expt 1, 7530 to 8200 kg DM/ha; Expt 2, 6390 to 6860 kg DM/ha). The relationships between liveweight change (LWC) or wool growth rates (WGR) and FO, during the period until pasture wilting at the lowest stocking rate (83 days in Expt 1; 76 days in Expt 2), were described by Mitscherlich equations. More than 74% of the variation in LWC or WGR was explained by differences in green FOO. In Expts 1 and 2 respectively, more than 90% of the maximum liveweight gain (66 and 192 g/day) was achieved at a FOO of 4000 or 3000 kg DM/ha, and sheep maintained weight at 2000 or 1000 kg DM/ha. More than 90% of the maximum WGR (22.3 and 19.0 g/day) was achieved at a FOO of 3000 or 2000 kg DM/ha. More than 70% of the variation in WGR was explained by LWC in both experiments. The slopes of the linear relationships were 0.047 g wool/g LWC in Expt 1, and 0.024 g wool/g LWC in Expt 2. At liveweight maintenance, sheep produced 15% less (Expt 1) or 25% less (Expt 2) wool than those grazed under conditions which allowed maximum rates of liveweight gain. Fibre diameter (FD) and length of wool grown were affected in the same manner as WGR by increases in FOO and hence LWC. In Expts 1 and 2 respectively, total clean wool weights were reduced by 17 and 9 g, mean FD by 0.05 and 0.02 microns and staple length by 0.35 and 0.13 mm, for each increase of one sheep/ha during the spring treatment periods. The effects of stocking rate in spring on annual wool production, mean FD and staple length were described by linear (P < 0.05 to P < 0.01) relationships. Standard deviation of midside FD (Expt 2), staple strength and position of break (both experiments) did not change significantly with stocking rate. These results indicate that grazing to a lower FOO during spring can be used to manipulate the amount and characteristics of wool produced by Merino wethers grazing annual pastures in Mediterranean climates with 600-700 mm rainfall.

Supplementation of young Merino sheep grazing annual pastures with lupin, barley grain, or silage

1993 ◽  
Vol 33 (4) ◽  
pp. 403 ◽  
Author(s):  
JJ Gardner ◽  
PT Doyle ◽  
JB Rowe ◽  
R Hetherington ◽  
P Spicer ◽  
...  
Keyword(s):  
Growth Rate ◽  
Energy Levels ◽  
Fibre Diameter ◽  
Barley Grain ◽  
Sheep Grazing ◽  
Merino Sheep ◽  
Wool Growth ◽  
Metabolisable Energy ◽  
Staple Strength ◽  
Fleece Weight

We examined the effects on liveweight change and wool production of supplements of lupin, barley grain, or silage given to Merino weaners (age 5-7 months; starting weight about 30 kg) grazing dry annual pastures. In experiment 1, each supplement was offered at 5 rates (g/sheep.day): lupin, air-dry, 75-450; barley, air-dry, 80-480; silage, fresh, 430-2580. Sheep on all treatments gained weight in the first 29 days of supplementary feeding, with no effect of rate of supplementation (lupin 97 g/day; barley 57 g/day; silage 74 g/day). Those receiving no supplement also gained weight (40 g/day). Different supplements were not compared because the energy levels of lupin and barley were not measured. Over the next 48 days, liveweight changes increased (P<0.001) linearly with rate of feeding of lupin (25 � 2.1 g/100 g) and barley (12 � 0.8 g/100 g). The trend with silage (11 � 5.0 g/kg) was not significant. Taken over the 77 days, liveweight changes increased (P<0.01) linearly with rate of feeding for lupin (20 �. 1.8 g/100 g), barley (8 �. 1.7 g/100 g), and silage (10 �. 2 g/kg). There were no significant (P>0.05) differences associated with the rate of supplementation for annual clean fleece weight (lupin 3.43 kg, barley 3.37 kg, silage 3.30 kg) or mean fibre diameter of the 12-month fleece (lupin 22.2 �m, barley 22.6 �m, silage 22.1 �m). In experiment 2, sheep were given no supplement, lupin, barley, or lupin and barley mixtures (metabolisable energy ratio, 1:3,1:1,3:1). All supplements increased liveweight change (P<0.01) and clean wool growth rates (P<0.05) compared with no supplement. There was also a trend towards an increase in total wool grown by supplemented sheep (3.8 - 4.00 v. 3.73 kg). Liveweight change during the first 71 days of feeding increased (P<0.01) as the proportion of lupin in the supplement increased, with no effects in the final 70 days of supplementation. During supplementation, clean wool growth rate increased (P<0.05) as the proportion of lupin in the mixture increased, but there was no significant effect on the total amount of wool grown over 12 months or on mean fibre diameter. Supplements resulted in increased (P<0.001) staple strength when compared with controls (21-25 v. 14 N/ktex).

scholarly journals THE EFFECTS OF FEED ON THE INTAKE, DIGESTIBILITY AND GROWTH RATE OF WEST AFRICAN DWARF GOATS FED GLIRICIDIA sepium AND LEUCAENA LEUCOCOEPHALA

2021 ◽  
Vol 22 (2) ◽  
pp. 164-168
Author(s):  
S. M. Odeyinka ◽  
A. A. Ademosun
Keyword(s):  
Growth Rate ◽  
Dry Matter ◽  
Gliricidia Sepium ◽  
West African ◽  
Dry Matter Intake ◽  
West African Dwarf ◽  
West African Dwarf Goats ◽  
Significant Difference ◽  
Different Levels ◽  
Dwarf Goats

The study evaluated the effects of level of feed offer on dry matter intake (DMI) , digestibility, the parts of plants selected and on the growth rate of West African dwarf (WAD) goats without resulting in toxicity. Seven different levels of feed offer ranging from 40g/kg0.75/day to 130Wkg0.75/day in increments of 15g/kg0.75) were fed to two groups of goats. The first group was fed 100% Gliricidia while the while the second was fed 50% Gliricidia and 50% Leucaena diet (50/50). The level of feed offer had significant effect on the DIM and digestible DMI (DDMI) of the goat (P < 0.01). The Leucaena intake in a 50/50 diet was always higher than the Gliricidia intake except at 55g1kg0.75 offer level. The level of feed offer had significant effects on the parts of plants selected (P < 0.01.) and on the growth rate. The leaf intake was statistically higher than the stem intake (P < 0.01). All the goats on 40g/kg0.75 and 55g/kg0.75 on a 100% Gliricidia diet lost weight while only those on 40g/kg0.75 lost weight on a 50/50 diet. There was no significant difference in the growth rate of goats on feed offer levels of 70g to 130g/kg0.75 (P > 0.05). The study indicate that goats performance was higher on a mixed browse diet than on Gliricidia alone. Goats performed best at 100g/kg0.75 offer level.

scholarly journals PSX-2 Growth and lactating performance of ewes fed with different energy levels

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 467-468
Author(s):  
Fernanda F Santos ◽  
Luciano Brochine ◽  
Vanderlei Benetel Junior ◽  
Maria Laura R Coelho ◽  
Augusto H Gameiro ◽  
...  
Keyword(s):  
Body Weight ◽  
Milk Production ◽  
Body Condition ◽  
Dry Matter ◽  
Body Condition Score ◽  
Energy Levels ◽  
The Body ◽  
Metabolizable Energy ◽  
Significant Difference ◽  
Condition Score

Abstract The objective of this study was to evaluate the milk production, body weight, and body condition score (BCS) of ewes fed with different energy levels. Seventy-one ewes were used and distributed in three treatments according to the metabolizable energy (ME, Mcal/kg) levels in the diet: CTL = according to the NRC (2007) recommendation for each stage (gestation and lactation); PLUS = CTL plus 10% of ME per kilogram of dry matter; LESS = CTL less 10% ME per kilogram of dry matter. Body weight and body condition score were evaluated a week before the expected date of parturition, a week after giving birth, and at weaning (60 days). Dairy production was evaluated at 20, 30, 40, 50 and 60 days after giving birth by the indirect method of the two weighing. The experimental design was analyzed as randomized complete blocks. There were no differences on milk production during almost all the lactation curve. Only on day 50 (P = 0.051), CTL was still at peak, while LESS and PLUS had already decreased their production. However, at 60 days, all treatments were already with low production, justifying weaning in this period. Results of weight and BCS showed a significant difference in all periods evaluates. Ewes in the PLUS diet had greater BW and BCS. The BCS before giving birth is expected to be over 3.5 and treatment LESS was the only one that did not achieve this score (2.66, 3.37, 3.83 for LESS, CTL, and PLUS, respectively). At weaning, ewes fed PLUS and CTL had BCS of 3.51 and 2.92, respectively, but treatment LESS had only 1.82. That is prejudicial for the next mating seasonal and this animal. We concluded that LESS diet interfered with the body reserves of sheep.

Wool growth regulation by local skin cooling

1967 ◽  
Vol 9 (3) ◽  
pp. 393-397 ◽  
Author(s):  
J. M. Doney ◽  
J. G. Griffiths
Keyword(s):  
Heat Transfer ◽  
Growth Rate ◽  
Blood Flow ◽  
Growth Regulation ◽  
Fibre Diameter ◽  
Systemic Response ◽  
Local Cooling ◽  
Local Skin ◽  
Wool Growth ◽  
Skin Cooling

Local cooling of the skin, produced by exposure to wind was shown to depress the rate of length growth of wool. The depression was associated with reductions in skin temperature and blood flow and with increases in heat transfer in the exposed regions. Fibre diameter did not appear to be affected and there were no indications of a systemic response of wool growth rate to exposure.

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