Summer production of sheep grazing irrigated and non-irrigated pasture

1974 ◽  
Vol 14 (70) ◽  
pp. 613
Author(s):  
MJ Sharkey ◽  
JP Murphy ◽  
RG Ward ◽  
CG Winfield

At Werribee in southern Victoria changes in liveweight, wool growth and carcase weights were measured over a 96 day period in summer during which two-year-old Corriedale and Merino ewes grazed various combinations of irrigated perennial and non-irrigated annual pasture. To provide the different combinations of grazing, groups of each breed grazed the two pasture types for different periods of time in 8 or 32 day grazing cycles. Groups with an eight day grazing cycle spent 1, 2, 3, 4, 5, 6, or 7 days (the 32 day grazing cycle groups 4, 8, 12, 16, 20, 24 or 28 days) on the irrigated pasture before completing the grazing cycle on the non-irrigated pasture. Two other groups grazed on either irrigated or non-irrigated pasture throughout the 96 days and a further group was slaughtered on day 1 of the experiment to measure the effect of treatments on carcases. The results were examined by regression analysis and showed that both breeds declined in liveweight, carcase weight, and wool growth on non-irrigated pasture. Production improved with time spent on irrigation. Corriedales (initial liveweight 47.0 kg) fattened when grazed on irrigated pasture for 50 per cent or more of the time but Peppin Merinos (initial liveweight 40.1 kg) could not be fattened beyond their initia carcase weights on any treatment. Wool production increased linearly with time spent on irrigation and was greater in Corriedales than in Merinos. The sheep grazing pastures in consecutive 8 day cycles did not differ significantly in production from sheep on similar treatments in the 32 day cycle.

1987 ◽  
Vol 27 (3) ◽  
pp. 349 ◽  
Author(s):  
CW Thorn ◽  
MW Perry

Pasture production, pasture composition and quality, and liveweight, body condition and wool growth of Merino weaner wethers were monitored over 2 seasons and at 2 stocking rates (4 and 8 sheep/ha) on a mixed annual grass-legume pasture sprayed with propyzamide to control grasses. Propyzamide virtually eliminated annual grasses from the pasture (less than 5 kg/ha of grass dry matter in spring v. 403 kg/ha on untreated pasture in 1981) and this carried over into the second season (61 kg/ha v. 647 kg/ha in spring 1982). Propyzamide treated pastures had less total dry matter (P = 0.05) throughout 1981: however, except for a single sample date, there was no effect of propyzamide on total available pasture in the second season. Increased growth of clover and capeweed compensated for the absence of the grasses. The higher stocking rate reduced available clover, capeweed and total dry matter (P = 0.05) throughout both years. Sheep grazing grass-free pastures had lower liveweights during winter in both years, but made compensatory gains during late spring and summer consistent with the higher quality (1.6 v. 1.07% nitrogen when sampled in January) of propyzamide treated pastures. In 198 1, wool growth rates were reduced at the higher stocking rate and total clean wool production was reduced from 4.55 kg/sheep at 4/ha to 3.65 kg/sheep at 8/ha. Pasture treatment had no effect on wool production in either year. The implications of using selective herbicides to remove the annual grass component of legume-based annual pastures in south-western Australia are dis cussed in relation to pasture and sheep production.


1986 ◽  
Vol 8 (1) ◽  
pp. 46 ◽  
Author(s):  
RD Graetz

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.


1964 ◽  
Vol 15 (4) ◽  
pp. 676 ◽  
Author(s):  
LJ Lambourne

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.


2003 ◽  
Vol 11 ◽  
pp. 109-115
Author(s):  
T.N. Barry ◽  
P.D. Kemp ◽  
C.A. Ramirez-Restrepo ◽  
N. Lopezvillalobos

Lotus corniculatus (lotus) contains condensed tannins (CT; 25-35 g/kg DM), which reduce the microbial degradation of forage protein in the rumen and increase amino acid absorption from the small intestine. In grazing experiments at Palmerston North during the 1990s, sheep grazing L. corniculatus had superior wool production, body growth and ovulation rates (OR) relative to sheep grazing lucerne (Medicago sativa) or perennial ryegrass (Lolium perenne)/white clover (Tritolium repens) pasture. Polyethylene glycol (PEG) drenching studies showed that action of CT was responsible for a component of the increases in wool growth and OR, but not body growth, and increased milk yield in lactating ewes. The 'Massey lotus' programme moved in 2000 to Riverside farm in the Wairarapa, where L. corniculatus is more agronomically suited, and its integration into dryland farming systems is being studied. We aim to develop systems that increase animal productivity whilst also reducing chemical input, notably of anthelmintic drenches. In two experiments conducted over 12 weeks in spring, ewes and lambs grazing L. corniculatus without pre-lamb drenching had lower faecal egg counts (FEC) and lower dag scores than ewes and lambs grazing pasture. Also, liveweight gain (+44%), weaning weight (+26%) and wool production (+32%) were greater for lambs grazing lotus. Weaned lambs grazing L. corniculatus over 14 weeks in summer grew faster than those grazing pasture (298 cf. 201 g/day) when regularly drenched. Reduction of anthelmintic drenching reduced the growth rates of lambs grazing L. corniculatus, but at 228 g/day this was still much faster than those grazing pasture (187 g/day). Lambs grazing L. corniculatus with restricted anthelmintic grew slightly faster than regularly drenched lambs grazing pasture. In addition, ewes mated on L. corniculatus had greater ovulation rates, lambing % and weaning % (approximately 25%) than ewes mated on pasture. Lamb weaning weight was unaffected by the ewes grazing L. corniculatus during mating, but mortality rate during the period from birth to weaning was lower for lambs that were conceived when their dams were grazing lotus. Annual (dry matter) production under grazing averaged over two years (2000-2001), was 9.5 t/ha for L. corniculatus and 8.6 t/ha for pasture. The percentages of annual production that occurred in spring, summer, autumn and winter were 49, 40, 8 and 4%, respectively, for L. corniculatus and 55, 30, 9 and 6%, respectively, for pasture. L. corniculatus has potential as a specialist feed in dryland farming systems for use during mating to increase subsequent lambing percentage and to increase lamb growth while reducing anthelmintic use. The result is more lambs being drafted at an earlier age. Key words: agronomy, body growth, condensed tannins, dry matter yield, Lotus corniculatus, reproduction, sheep, withdrawing anthelmintic, wool growth


1970 ◽  
Vol 10 (47) ◽  
pp. 665 ◽  
Author(s):  
JP Langlands

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.


1981 ◽  
Vol 21 (110) ◽  
pp. 272 ◽  
Author(s):  
LG Butler

A field trial was conducted in the Wimmera region of Victoria to investigate the effect of several supplements on 4-year-old Merino wethers grazing a weed-free wheat stubble for 3 months, The four treatments were: a control (no supplement), urea/molasses block, 100 g/head day-1 of lupin grain, and 2 g urea plus 0.5 g Na2SO4 l-1 in the drinking water. Twenty sheep per treatment were used, and liveweight change and wool growth were measured. Although all groups lost weight, the lupin group lost only 0.5 kg per head over the 3 months of the trial, and was 3.8 kg heavier (P <0.01) than the control group, while the urea/molasses group was 2.2 kg heavier (P <0.01) than the control group. There was no effect of the urea plus sulfur supplement in the drinking water on liveweight or wool production. The urea/molasses block did not affect wool production but lupin grain stimulated wool production by 0.08 kg (P <0.05). The sheep were weighed and shorn four and a half months after the trial (August), during which time all groups grazed together on green feed. The experimental liveweight differences had disappeared, apparently due to compensatory growth. In addition, a digestibility trial was conducted in an attempt to explain some of the field results. The treatments were designed to simulate those used in the field. Lupin grain stimulated intake by 129 g day-1 (P <0.05) but had no effect on apparent digestibility of straw. The treatment simulating the urea/ molasses block (urea plus sulfur plus sucrose in the drinking water) stimulated intake by 159 g day-l (P <0.05) and tended to increase digestibility (P > 0.05). It was concluded that supplementary feeding of Merino wethers grazing weed-free stubble is unlikely to be an economic farm practice.


2007 ◽  
Vol 13 ◽  
pp. 259-262
Author(s):  
K.N. Tozer ◽  
S. Ates ◽  
N.R. Mapp ◽  
M.C. Smith ◽  
R.J. Lucas ◽  
...  

Pasture growth, botanical composition and sheep grazing preference were measured over 20 months in tall fescue (cultivar Advance), without endophyte (Nil) or infected with AR542 (MaxPTM) endophyte, and clover pastures sown into a dryland soil, Canterbury, New Zealand. Pastures were rotationally grazed with sheep, with grazing preference for the two endophyte treatments measured in late autumn and early spring. Annual dry matter production from April 2004 to April 2005 was not significantly different between AR542 (6293 kg DM/ha) and Nil (5864 kg DM/ha) tall fescue. The number of tall fescue plants/m2 and their basal diameter was greater for AR542 (35 plants/m2, 7.5 cm diameter) than Nil endophyte tall fescue (28 plants/m2, 6.8 cm diameter). AR542 endophyte tall fescue pastures had fewer weeds, mainly annual grasses, than Nil endophyte pastures throughout the trial. Grazing preference, measured by the number of sheep grazing each plot, and decline in pasture height did not differ between Nil and AR542 tall fescue. Keywords: tall fescue, novel endophyte, AR542, botanical composition, weed, grazing preference


1974 ◽  
Vol 14 (66) ◽  
pp. 17 ◽  
Author(s):  
KW Entwistle ◽  
G Knights

The performance of unsupplemented Merino ewes grazing dry season semi-arid tropical pastures was compared with that of other sheep supplemented with either urea-molasses or molasses. Over the experimental period from September 1970 until late January 1971 mean daily intakes per head of urea and molasses respectively were: low urea group, 11.7 g and 35.1 g; high urea group, 15.2 g and 45.6 g; molasses, 38.9 g. Monthly estimates of the proportions of animals consuming the supplement over the period September to January varied from: urea-molasses-71 per cent to 97 per cent; molasses-75 per cent to 96 per cent. Unsupplemented sheep lost significantly more liveweight than did supplemented groups in the period September to February. However, during the period of greatest nutritional stress from December to February, sheep recewing molasses lost significantly more weight than did those supplemented with urea-molasses, and liveweight loss was greater in the low urea group than in the high urea group. Wool growth rates were significantly higher in groups receiving urea-molasses, with highest wool growth rates in animals on the high level of urea. Total fleece weights were unaffected by treatment as were the reproductive factors examined. Faecal nitrogen levels declined until the onset of pasture regrowth in February and were associated with low digestibility of the available forage. Compensatory liveweight gains following pasture regrowth outweighed any advantage of the dry season supplementation. It was concluded that urea-molasses supplements were of little direct benefit to sheep grazing these pastures.


1948 ◽  
Vol 1948 (01) ◽  
pp. 7-21 ◽  
Author(s):  
S. J. Watson

The use of the animal as a means of evaluating pasture is an obvious approach to the problem, since this is the form in which the practical man will ultimately measure the return from his grassland. If anything has to be sacrificed it is the sward and not the animal, a point too often overlooked in our grassland work generally. Though many grazing trials of an observational nature are to be found in the early agricultural literature, the earliest experimental work was most probably that of the late Sir William Somerville. When Professor of Agriculture at Newcastle in 1897, he commenced the world-famous experiment at Cockle Park Agricultural Experimental Station on pasture improvement. An effort was then made to measure the effect of various systems of manuring in terms of the live-weight increase of sheep grazing on the different plots. In this experiment on Tree Field the relative values of the different systems of manuring were measured by weighing the sheep before and after the experimental period. In the early years the plots were stocked with hoggs, but in order to get closer grazing lambs and ewes are now used and have shown greater increases per acre.


2009 ◽  
Vol 49 (12) ◽  
pp. 1100
Author(s):  
B. J. McGuirk

Early work in the 1950s on the wool growth response of sheep from diverse genotypes for wool production in response to varying planes of nutrition at pasture did not show the significant genotype × environment interactions exhibited in later pen studies with the same or very similar genotypes. However, this early study used a log-transformation on all traits to adjust nutritional effects for scale. Re-analysis of the original (i.e. untransformed) data shows that superior genetic merit for clean fleece weight, different sire progeny groups or selection flocks is more apparent when hogget ewes are fed a high plane of nutrition at pasture. However, only in the case of flocks was the interaction statistically significant, and this interaction was insignificant when data were either log-transformed, or when an appropriate test that accounts for scale-type effects was applied. When left untransformed, the data are, thus, in agreement with the subsequent pen studies that examined data on untransformed clean wool production.


Sign in / Sign up

Export Citation Format

Share Document