Managing the weaning transition of Merino lambs by promoting positive growth rates and increasing survival – is yard weaning a viable option?

2012 ◽  
Vol 52 (7) ◽  
pp. 516 ◽  
Author(s):  
S. Gabb ◽  
S. Hatcher ◽  
J. Eppleston ◽  
B. Watt ◽  
K. J. Thornberry

The effectiveness of yard weaning to manage the weaning transition period for Merino sheep was investigated on three commercial properties in the New South Wales Central Tablelands. Three experiments were conducted, Experiment 1 investigated the duration of yard weaning, Experiment 2 compared two alternative rations provided to yard-weaned animals, while Experiment 3 compared yard weaning with paddock weaning. The ‘Control’ for each of the three experiments was each producers’ normal paddock-weaning strategy with comparisons based on post-weaning growth rates and weaner survival. Liveweights were recorded at weaning and at 15, 50 and 180 days post-weaning. Growth rates were calculated from liveweight measurements. Survival was determined by the continuing presence of an individual animal at subsequent measurements. Compared with the paddock-weaned Control group, variable responses in liveweight, growth rates and weaner survival to 50 and 180 days post-weaning occurred in the three experiments. Yard weaning was not superior to any of the producers’ normal paddock-weaning practices, however, favourable seasonal conditions in early 2010 prompted high growth rates in the paddock-weaned Control animals relative to those achieved by the yard-weaned animals. Further research is required to determine the optimum duration of confinement and ration (including composition and method of delivery). This work should include comparisons of the behaviour of paddock- and yard-weaned animals and model production benefits versus economic costs for a range of production systems and market scenarios.

2017 ◽  
Vol 57 (5) ◽  
pp. 958 ◽  
Author(s):  
M. L. Dever ◽  
L. P. Kahn ◽  
E. K. Doyle

This experiment tested the hypothesis that integrated parasite management (IPM) programs would reduce the effects of gastrointestinal nematodes (GIN) in meat-breed lamb production systems on the Northern Tablelands of New South Wales. The experiment was a longitudinal experiment using twin-bearing Border Leicester × Merino ewes on farms managed in accordance to either regional WormBoss IPM programs (n = 3 farms) or typical (TYP) regional GIN control (n = 2 farms). Ewes on each farm were either GIN-suppressed (SUP; n = 120 ewes) or not (NSUP; n = 120 ewes) and were managed in two groups (n = 120/group) balanced for GIN control. Ewes lambed in September and at lamb marking, 120 lambs (Dorset sires) from each ewe GIN control group were enrolled in the experiment to investigate the effect of ewe GIN control on lamb performance up to weaning. Overall mean worm egg count (WEC) of ewes (P = 0.004) was lower with IPM (IPM 766 vs TYP 931 epg) and was achieved with fewer drenches (IPM 4.5 vs TYP 5.5/year). Despite lower WEC, GIN infection reduced liveweight (IPM –2.1 kg vs TYP –1.1 kg, P = 0.0006) and clean fleece weight (IPM –0.11 kg vs TYP –0.01 kg, P = 0.03) of ewes to a greater extent on IPM farms. The annual rate of apparent ewe mortality was 6.5% and this was unaffected by GIN infection. WEC of lambs at weaning was lower on IPM farms (IPM 159 epg vs TYP 322, P < 0.0001) but the difference in weaning weights of lambs reared by NSUP and SUP ewes was greater on IPM farms (IPM –1.1 kg vs TYP 0.2 kg, P < 0.0001). Overall, the production loss due to GIN infection in these sheep-meat production systems, on the Northern Tablelands of New South Wales, was small and treatment frequency can be reduced by IPM programs.


Proceedings ◽  
2021 ◽  
Vol 77 (1) ◽  
pp. 20
Author(s):  
Adrian Cherney

In recent years, there has been a proliferation of programs aimed at preventing radicalization and disengaging known violent extremists. Some programs have targeted individuals through the use of case management approaches and the development of individual intervention plans (e.g., the Desistance and Disengagement Program and the Channel program in the UK; the Australian New South Wales Corrections Proactive Integrated Support Model—PRISM—and state-based division initiatives in Australia). There is a broad consensus in the literature that the evaluation of such initiatives has been neglected. However, the evaluation of case-managed interventions to counter violent extremism (CVE) is challenging. They can have small caseloads which makes it difficult to have any comparison or control group. Client participation can vary over time, with no single intervention plan being alike. This can make it hard to untangle the relative influence of different components of the intervention on indicators of radicalization and disengagement. In this presentation, results from primary research that set out to evaluate case-managed CVE interventions in Australia and develop evaluation metrics are presented. This research involves the examination of interventions implemented by New South Wales corrections and state police. The effectiveness of these interventions was assessed against a five-point metric of client change. Client change overtime was analyzed using case note information collected by the various interventions on client participation. Results show that client change is not a linear process and that the longer an individual is engaged in a case-managed intervention, the more likely they are to demonstrate change relating to disengagement. Specific case studies are used to illustrate trajectories and turning points related to radicalization and to highlight the role of case-managed interventions in facilitating disengagement. Key elements of effective interventions include the provision of ongoing informal support. Investment in capturing case note information should be a priority of intervention providers. Different challenges confronted by case-managed CVE interventions are highlighted.


Parasitology ◽  
1982 ◽  
Vol 85 (1) ◽  
pp. 21-25 ◽  
Author(s):  
M. G. Smeal ◽  
A. D. Donald

SUMMARYOn a coastal farm in New South Wales where beef and dairy cattle production was carried on side-by-side, separate pasture plots were contaminated with eggs of Ostertagia ostertagi by calves from each production system in autumn, winter or spring. Successive groups of parasite-free tracer calves grazed on the plots for 14 days at 4-week intervals and were then killed for worm counts 14 days after removal from pasture. On all plots, the proportion of inhibited early 4th-stage larvae in tracer calves reached a maximum in spring, and was consistently and very significantly higher in calves which grazed plots contaminated with O. ostertagi of beef cattle origin. Factors which may be responsible for this difference between beef and dairy cattle populations of O. ostertagi are discussed.


2008 ◽  
Vol 48 (7) ◽  
pp. 966 ◽  
Author(s):  
S. Hatcher ◽  
J. Eppleston ◽  
R. P. Graham ◽  
J. McDonald ◽  
S. Schlunke ◽  
...  

Two monitoring projects were conducted to investigate weaner mortality in commercial Merino flocks in the Yass and the Central Tablelands Rural Lands Protection Boards located in the Southern Tablelands agricultural region of New South Wales. The projects were conducted in Yass in 2005 and in the Central Tablelands in 2006. A random sample of weaners from four flocks in the Yass board and 11 flocks in the Central Tablelands board were regularly weighed, growth rates were calculated after weaning and survival was determined by the continuing presence of an individual weaner at subsequent weighing activities. Weaning weight was the most important factor in determining postweaning liveweight, growth rates and survival with the significant impact of weaning weight on liveweight persisting for up to 6 months after weaning. Despite the lightest weaners being capable of considerable compensatory growth given sufficient postweaning nutrition, the lightest 25% of weaners were more than twice as likely to die as heavier weaners. A focus on ewe nutrition and parasite control during late pregnancy and lactation will allow Merino producers to achieve higher weaning weights that will set their weaners up for strong postweaning growth with a decreased likelihood of mortality.


1980 ◽  
Vol 20 (102) ◽  
pp. 9
Author(s):  
ID Sanderson ◽  
JD McFarlane ◽  
WR McManus

An experiment was conducted on the Central Western Slopes of New South Wales with Dorset Horn x Merino lambs to assess their liveweight gains during summer when weaned on to a lucernebased pasture under dryland conditions, and when weaned on to irrigated lucerne and red clover pastures. Lambs grazing irrigated lucerne, irrigated red clover and dryland lucerne had average growth rates of 155, 178 and 124 g day-1/head, respectively, throughout the 106 day experimental period. The poor growth rates of lambs on the dryland lucerne were apparently due mainly to the low digestibility of the dry feed on offer as a result of low rainfall, which also caused feed supply to be limiting during part of the experimental period. Lamb growth and intake data suggest that the diets selected from the red clover were of higher digestibility than those selected from the irrigated lucerne. It was concluded that irrigated red clover and irrigated lucerne provided useful diets for young lambs in this environment, although the growth rates achieved were less than reported elsewhere for these species in cooler climates. Growth rates achieved by lambs grazing dryland lucerne were less satisfactory for prime lamb production.


1979 ◽  
Vol 19 (99) ◽  
pp. 437 ◽  
Author(s):  
AC Andrews ◽  
FC Crofts

Four ecotypes of hybrid Bermudagrass (Cynodon dactylon) were compared with common couch (C. dactylon) and kikuyu (Pennisetum clandestinum) at five sites in coastal districts of New South Wales. The sites were Grafton and Coaldale (Lat. 30�S), Mitchells Island (Lat. 32�S) and Richmond and Badgerys Creek (Lat. 34�S). Hybrid Bermudagrass ecotypes 6389 and 692 were established quickly at all sites while ecotypes 71 9 and 632 were satsifactory. Kikuyu was strong at all sites except Grafton but the rate of establishment of common couch was poor. At the frost-free sandy site of Mitchells Island, Bermudagrass ecotypes 719, 692, 6389, and 632 outyielded kikuyu by 75, 65, 65 and 35%, respectively. However, at Grafton and Coaldale, the highest yielding Bermudagrass ecotype, 719, had only 35% higher production than kikuyu. At the frost prone southern sites of Richmond and Badgerys Creek, the annual production of kikuyu was equal to that of ecotypes 719, 6389, 692 and 632. Common couch yields were equal to kikuyu at all sites except at Richmond. At Mitchells Island, the hybrid Bermudagrasses outyielded kikuyu in spring, summer and early autumn but in the late autumn kikuyu had equal and sometimes higher growth rates than the best Bermudagrasses. In winter, the growth of both species was negligible, although kikuyu, unlike the Bermudagrasses, did produce some new shoots at the base of the sward. Data on persistence under grazing were collected from only three of the sites but trends were similar to establishment. Ecotype 6389 had the highest persistence rating of the Bermudagrasses. Kikuyu failed at the poorly drained sandy site of Grafton but remained strong at the other sites. It was concluded that hybrid Bermudagrasses were of potential value for pastures in New South Wales, especially for sites with sandy soils and low frost incidence.


2004 ◽  
Vol 55 (5) ◽  
pp. 489 ◽  
Author(s):  
John Stewart ◽  
Douglas J. Ferrell ◽  
Bryan van der Walt

The size and age compositions of yellowtail kingfish (Seriola lalandi) were studied in commercial landings in New South Wales, Australia between 1998 and 2000. The fishery was dominated by fish smaller than 65 cm fork length and these fish were estimated to be 2 and 3 year olds. Estimates of growth rates were made using size-at-age data from sectioned otoliths. The oldest yellowtail kingfish found was 21 years and measured 136 cm fork length. There were no differences in the growth rates between regions or between sexes. Yellowtail kingfish grow rapidly and reach their minimum legal length of 60 cm total length at around 2 years of age. These estimates showed that previous studies, which estimated ages using whole otoliths, may have underestimated the ages of older yellowtail kingfish. Total instantaneous mortality rates generated from catch curves ranged between 0.43 and 0.79. Yield per recruit models suggest that the population is currently growth overfished. The information provided is used to discuss the suitability of the current minimum legal length for yellowtail kingfish in New South Wales.


2001 ◽  
Vol 23 (2) ◽  
pp. 194 ◽  
Author(s):  
Andy Sharp ◽  
Kerry Holmes ◽  
Melinda Norton ◽  
Adam Marks

Between winter 1995 and winter 1998, seasonal spotlight counts for rabbits were conducted along three transects in western New South Wales. Rabbit Calicivirus (RCV) arrived at the study site in spring 1996 and had an immediate marked effect on rabbit densities. Prior to the advent of Rabbit Calicivirus Disease (RCD), rabbit abundance followed the expected annual pattern of positive growth during the winter to summer period and negligible or negative growth during the summer to winter period. With the arrival of RCV, rabbit abundance was observed to decline by 47% and 75% within low density populations and by 84% within a medium density population. In the subsequent 21 months, the low density populations returned to levels approximating those prior to the arrival of RCV. In contrast, rabbit abundance within the medium density population remained at consistently lowered levels. These data suggest that RCD will have a minimal effect on semi-arid zone rabbit populations below a density of 0.4/ha and that additional management actions will be required to further reduce rabbit abundances.


1992 ◽  
Vol 43 (5) ◽  
pp. 1033 ◽  
Author(s):  
RA Faragher

Growth rates of finclipped rainbow trout (Oncorhynchus mykiss) released into Lake Eucumbene, New South Wales, at an age of 0+ years were examined for each year between 1986 and 1988. Traps and nets yielded significant numbers of marked fish for validation of age estimation and length backcalculation from scale reading. Poor recognition of the marks by anglers was confirmed, indicating that survival of the fish was higher than was implied by angling returns. The diffuse nature of the second annulus in scales provided initial difficulty in ageing, particularly because of a similarly diffuse false check formed during the second year. Care was required in separating the annuli after asymptotic growth was reached (3 years), Growth rates in Lake Eucumbene were comparable with those found in studies in Tasmania and Victoria. Back-calculated lengths were in agreement with those from fish of known ages. The presence of finclipped fish aged 2 + and 3 + years in a spawning population confirmed that stocked fish contributed to the spawning stocks. The study reconfirms the importance of validation of ageing techniques in fisheries investigations.


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