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1
Pannier, L., E. N. Ponnampalam, G. E. Gardner, D. L. Hopkins, A. J. Ball, R. H. Jacob, K. L. Pearce e D. W. Pethick. "Prime Australian lamb supplies key nutrients for human health". Animal Production Science 50, n. 12 (2010): 1115. http://dx.doi.org/10.1071/an10132.
Testo completoAbstract (sommario):
This study investigated genetic and non-genetic factors affecting the iron, zinc and omega-3 fatty acid levels of fresh lamb meat. Results from the 2007 progeny of the Australian Sheep Industry Cooperative Research Centre Information Nucleus flock, ~2000 lambs, are presented here. The average level of iron and zinc in lamb muscle was 2.05 and 2.31 mg/100 g, respectively. The iron level was 103% of that required to claim lamb as a ‘good source’ of iron for men of all ages and women older than 50 years, and the average level of zinc was 116% of that required to claim lamb as a ‘good source’ of zinc for women, but was insufficient for a ‘good source’ claim for men. The iron and zinc content of muscle were affected (P < 0.001) by age at slaughter, sex, site at which the lambs were reared, and sire (independent of breed). Lambs from all sites reached the ‘source’ claim for iron for all adults and lambs from all sites, expect lambs from the Cowra and Hamilton sites, had greater iron levels than that required for a ‘good source’ claim for men and women over 50 years old. For zinc, all sites reached the ‘source’ and ‘good source’ claim for men and women, respectively. The major sources of variation in omega-3 fatty acid levels were site and kill group within site (P < 0.001), most likely reflecting nutritional differences associated with the availability of green feed. The eicosapentaenoic acid + docosahexaenoic acid values for all sites indicated that lambs from the Cowra, Rutherglen and Struan sites had adequate levels for a ‘source’ claim of omega-3. The overall average level of eicosapentaenoic acid + docosahexaenoic acid in lamb meat was 23.5 mg/100 g, which is higher than the level required to claim lamb as a ‘source’ of omega-3. The effect of sire on omega-3 fatty acid level was small, but statistically significant (P < 0.001). These results confirm that lamb can represent a ‘source’ or ‘good source’ of these nutrients.
2
Hopkins, D. L., E. S. Toohey, K. L. Pearce e I. Richards. "Some important changes in the Australian sheep meat processing industry". Australian Journal of Experimental Agriculture 48, n. 7 (2008): 752. http://dx.doi.org/10.1071/ea07393.
Testo completoAbstract (sommario):
In the last 5 years there has been a dramatic increase in the adoption in the Australian sheep meat processing industry of electrical technologies designed to streamline processing and improve product quality. Part of this change was initiated by an Australia-wide audit of lamb tenderness in 1997–98 and the development of a program to establish an eating quality scheme for sheep meat across Australia. Critically, these initiatives coincided with the development of new ways of administering electrical currents to either bodies or carcasses. Underlying this new approach is the electrocution of carcasses individually on segmented electrodes in a dose responsive way with electricity that has short pulse widths and lower voltages. This paper documents the pivotal factors which have contributed to this level of industry adoption and which has seen 14 abattoirs install the new technology. Of these abattoirs only one previously had any form of stimulation and these abattoirs represent more than 70% of the throughput of sheep and lambs on a tonnage basis per year in Australia.
3
Hutchison, Dayna, Bronwyn E. Clarke, Serina Hancock, Andrew N. Thompson, Elise Bowen e Caroline Jacobson. "Lower Reproductive Rate and Lamb Survival Contribute to Lower Lamb Marking Rate in Maiden Ewes Compared to Multiparous Ewes". Animals 12, n. 4 (18 febbraio 2022): 513. http://dx.doi.org/10.3390/ani12040513.
Testo completoAbstract (sommario):
Suboptimal reproductive performance of maiden (primiparous) ewes remains a source of inefficiency for the Australian sheep industry. However, the extent and causes of the poorer reproductive performance of maiden ewes on Australian sheep farms are not well understood. Here, we show the reproductive performance of maiden ewes relative to their multiparous counterparts on the same farms across Australia using a cohort survey. The difference in marking rate for non-Merino maiden ewe lambs compared to multiparous ewes was 58% (74 vs. 132%; p < 0.001), and this was attributable to a 50% difference in reproductive rate (109 vs. 159%; p < 0.001) and 16% difference in lamb survival to marking (67 vs. 83%; p < 0.001). The difference in marking rate for maiden Merino two-tooth ewes lambing at approximately 2 years-of-age compared to mature multiparous ewes was 22% (80 vs. 102%; p < 0.001) and this was attributable to a 24% difference in reproductive rate (108 vs. 132%; p < 0.001) and 3% difference for lamb survival (75 vs. 78%; p < 0.05). Positive correlations for reproduction traits (reproductive rate, lamb survival and marking rate) between maidens and multiparous ewes were observed for maiden Merino two-tooth ewes (p < 0.001), but these correlations were weak or non-existent for non-Merino ewe lambs. Strategies to improve both reproductive rate and lamb survival can address the poorer and more variable reproductive performance of maiden ewes.
4
Brash, LD, NM Fogarty e AR Gilmour. "Reproductive performance and genetic parameters for Australian Dorset Sheep". Australian Journal of Agricultural Research 45, n. 2 (1994): 427. http://dx.doi.org/10.1071/ar9940427.
Testo completoAbstract (sommario):
Reproductive performance of ewes in a large Dorset stud flock is reported. The data included 2488 ewes with 10016 joining records over 25 years. Average performance for reproductive traits were: fertility 92%, litter size 1.31, neonatal lamb survival 91%, lamb survival to weaning 85%, with overall lambs born 1.20 and lambs weaned 1.02 per ewe joined. Differences between breeds (Poll Dorset and Dorset Horn), season of birth (spring and autumn) and season of joining (spring and autumn) were significant for most reproduction traits. Linear and quadratic regressions for age of ewe at joining were highly significant for all traits (P < 0.001) with maximum performance between three and six years of age. Estimates of heritability for ewe reproductive traits were: 0.062 � 0-02 for number of lambs born and 0.04 � 0.01 for number of lambs weaned per ewe joined, and component traits, 0.02 �0 -01 for fertility, 0 08 � 0 -02 for litter size and 0.00 � 0.01 for lamb survival. Estimates of repeatability were less than 0.14 for all the reproduction traits, which resulted in substantially higher predicted heritabilities when repeated records were used. Heritability estimates for average ewe lifetime performance, with approximately four records, were 0.08 � 0 06 for lambs born, 0.12 � 0.05 for lambs weaned, 0.08 � 0.04 for fertility, 0.l9 � 0 -04 for litter size and zero for lamb survival. The genetic correlations between litter size and lambs born and weaned were close to unity, whereas those for fertility were lower and declined from lambs born (0.6l � 0.22) to lambs weaned (0-45 � 0.30). The estimated heritability for ewe longevity, defined as the number of years the ewe remained in the breeding flock, was 0.00 � 0.03. The potential for genetic improvement in reproductive rate is discussed in relation to other reports in the literature and in the context of the roles of the Dorset breed in the Australian lamb industry. Increased reproductive rate in Dorset flocks impacts on stud profitability and the rate of genetic improvement from selection for other traits such as liveweight. The parameter estimates derived will be used in compiling breed-specific parameter sets for genetic evaluation in LAMBPLAN.
5
Refshauge, G., F. D. Brien, G. N. Hinch e R. van de Ven. "Neonatal lamb mortality: factors associated with the death of Australian lambs". Animal Production Science 56, n. 4 (2016): 726. http://dx.doi.org/10.1071/an15121.
Testo completoAbstract (sommario):
The objective of the present study was to examine the factors associated with the death of neonatal lambs. Postmortem autopsy data were collected from 3198 newborn lambs in the Sheep CRCs Information Nucleus Flock situated in various environments throughout southern Australia. The proportion dying by category from highest to lowest was starvation–mismothering (25%), stillbirth (21%), birth injury (18%), dystocia (9%), death in utero–prematurity (10%), predation (7%), cold exposure (5%), undiagnosed (4%), infection (1%) or misadventure (1%). Factors best explaining the probability of lambs falling into a death category included both birth type and birthweight for dystocia, stillbirth, starvation–mismothering and death in utero–prematurity. The probability of a lamb falling into any category was predicted at the mean birthweight, within birth type. Single-born lambs were more likely to die from dystocia and stillbirth, while twin lambs were more likely to die from birth injury, starvation–mismothering or from undiagnosed causes. Triplet lambs were more likely to die from starvation–mismothering or death in utero–prematurity. Sire type (Merino, maternal or terminal) did not affect the proportions of lambs within any category. The proportions lost to each cause of death were largely consistent among locations, despite the rate of death varying. Dystocia, stillbirth and birth injury, as evidenced by the presence of oedema around the head and neck or by lesions of the central nervous system, accounted for 48% of autopsied lambs. We conclude that for improvements to occur in the rates of lamb survival, the Australian sheep industry must focus on minimising losses due to dystocia, stillbirth, birth injury and starvation.
6
Kopp, Kayla, Marta Hernandez-Jover, Susan Robertson, Angel Abuelo e Michael Friend. "A Survey of New South Wales Sheep Producer Practices and Perceptions on Lamb Mortality and Ewe Supplementation". Animals 10, n. 9 (5 settembre 2020): 1586. http://dx.doi.org/10.3390/ani10091586.
Testo completoAbstract (sommario):
High lamb mortality rates reduce profitability and reduce the perceived animal welfare standards of the industry. This study aimed to understand producer knowledge of lamb mortality rates and causes of lamb mortality, and to investigate various practices and perceptions of producers that may contribute to lamb deaths. Postal and online surveys gathered data on Australian sheep producer’s knowledge and practices around lambing and management practices. Based on results, approximately 50% of producers estimated less than 10% mortality of lambs between birth and marking, compared to published data estimates of 20–25% mortality. Pre-lambing vaccination of ewes was not undertaken by 10–20% of producers. Ninety-six percent of producers vaccinated lambs; however, 17% of Merino and 23% of crossbred lamb producers only gave a single vaccination instead of the recommended initial vaccine and booster. The lower estimated mortality impacts producer’s perceived benefits of management strategies being undertaken. Research undertaken needs to be more effectively distributed to producers via extension services to ensure producers understand the causes of mortality. Important messages to convey to producers include the limited impact of predation in most cases and the total costs of lamb mortality on-farm.
7
Schmoelzl, Sabine, e Fran Cowley. "The case for pre-parturient selenium and iodine supplementation of ewes for improving lamb survival". Animal Production Science 56, n. 8 (2016): 1263. http://dx.doi.org/10.1071/an15362.
Testo completoAbstract (sommario):
Lamb survival is an issue of high relevance to the Australian sheep industry, as lamb-survival rates have direct bearing on overall reproductive performance of the sheep, and also constitute a main concern from an animal welfare perspective (Mellor and Stafford 2004). Both genetic and management factors play an important role in this complex issue (Hinch and Brien 2014). Ewe nutrition is of particular relevance as the intrauterine growth conditions prepare the lamb for the crucial transition to life outside the uterus. Effects of body condition of the ewe during various stages of the pregnancy have been investigated in detail, yet much less is known about the critical role of micronutrient provision to the ewe. Although several risk factors for selenium (Se) and iodine (I) subclinical deficiencies exist for sheep on pasture in Australia, determining micronutrient status in sheep or pasture is not straightforward. Several studies have separately found effects of Se and I supplementation on lamb survival. Studies investigating the interaction of Se and I supplementation have been few but results have demonstrated an interaction between Se and I. With increased twinning rates as a result of increased selection of numbers of lambs weaned, nutritional demands during pregnancy across flocks are increasing, and effects of micronutrients on lamb health and survival have greater impact. New opportunities in nutritional research are encouraging new studies into the effects of Se and I supplementation on lamb survival.
8
Brien, F. D., S. W. P. Cloete, N. M. Fogarty, J. C. Greeff, M. L. Hebart, S. Hiendleder, J. E. Hocking Edwards et al. "A review of the genetic and epigenetic factors affecting lamb survival". Animal Production Science 54, n. 6 (2014): 667. http://dx.doi.org/10.1071/an13140.
Testo completoAbstract (sommario):
Poor lamb survival pre-weaning is a major source of reproductive inefficiency in Australian sheep flocks. While nutrition and management options have been extensively researched and promoted to improve lamb survival, the present review focuses on the prospects for obtaining genetic gain and helps identify selection strategies for boosting such gains to improve overall reproductive efficiency in the Australian sheep industry. Estimated heritability for lamb survival using linear model analysis is low, although use of threshold models suggests that heritability could be higher, which, if true, could help explain the substantial genetic gains obtained in long-term selection experiments. Epigenetic mechanisms may hinder selection and quantitative trait-loci identification through confounding and/or masking genetic variances and co-variances. With sufficient information, these effects could be considered in genetic evaluations by identifying those components that are amenable to selection. Regarding indirect selection, finding effective criteria for improving lamb survival has proved elusive. Most measures of maternal behaviour, temperament and lambing difficulty researched are poorly correlated genetically with lamb survival. Of lamb behaviours and thermo-genic indicators studied, latency to bleat following handling by humans is moderately genetically correlated with lamb survival, as is neonatal rectal temperature. Industry application remains to be adequately explored for the more promising of these measures. Finally, in lieu of direct selection for lamb survival, there is merit in selecting for multiple-rearing ability or its equivalent, possibly with additional selection criteria for lamb survival and reproductive efficiency.
9
Hopkins, D. L. "Processing technology changes in the Australian sheep meat industry: an overview". Animal Production Science 51, n. 5 (2011): 399. http://dx.doi.org/10.1071/an10258.
Testo completoAbstract (sommario):
Over the last 20 years the Australian sheep industry, particularly the lamb meat sector, has undergone a major change in focus such that consumer requirements are a paramount determinant for production and processing developments. As a result automatic accurate methods of measuring carcasses for traits like fatness and meat yield have been important to aid a reduction by industry in carcass fat levels in line with domestic and international consumer demand. This occurred while carcass weight increased due to a range of genetic and production factors implemented on-farm. Further to this in the last 5–7 years there has been a dramatic increase in the adoption of electrical technologies based on new methodologies with a shift in focus onto eating quality. Underlying this new approach was the electrical stimulation of individual carcasses on segmented electrodes in a dose-responsive way with electricity that has short pulse widths and low to medium voltages and is thus much safer than the original high voltage systems. This technology allowed stimulation units to be fitted into abattoirs where this was not previously possible and validation showed that the technology could reduce toughness in lamb destined for the domestic market and some export markets. More recent technology to stretch and shape cuts shows promise for improving both the quality and product range from sheep and lamb carcasses. The industry continues to focus on meat quality and has shown a significant increase in exports, while maintaining per-capita domestic consumption at record retail prices. This indicates an industry where research investment across the board has shown significant returns.
10
Russell, B. C., G. McAlister, I. S. Ross e D. W. Pethick. "Lamb and sheep meat eating quality — industry and scientific issues and the need for integrated research". Australian Journal of Experimental Agriculture 45, n. 5 (2005): 465. http://dx.doi.org/10.1071/ea04007.
Testo completoAbstract (sommario):
This paper provides an introduction to the special edition of the Australian Journal of Experimental Agriculture dedicated to an integrated research program aimed at understanding the critical control points which determine the consumer defined eating quality of Australian lamb and sheep meat. The reasons for a general approach in the research is outlined.
11
Watkins, Peter. "Chemical lean determination of boneless beef and lamb using a halogen moisture analyser". Animal Production Science 61, n. 7 (2021): 715. http://dx.doi.org/10.1071/an20445.
Testo completoAbstract (sommario):
Context Chemical lean (CL) is an important metric used by the Australian meat industry to describe fat content of meat product. It is a minimum meat specification included in contracts between Australian vendors of bulk packed boneless manufacturing meat and overseas or domestic buyers and can be regarded as the complement of chemically determined fat in meat (% fat, CL = 100-% fat). The microwave moisture method is commonly used for measuring CL content of meat in Australian abattoirs, relying on a relationship between CL and moisture content of boneless meat. It is regarded as a quick and easy method to use. More recently, newer methods for moisture analysis have become available which may also be suitable for CL determination, including commercial halogen moisture analysers (HMAs). HMAs use a halogen lamp as a source of infrared radiation that is absorbed by a sample, which then results in moisture loss. Aims This study aimed to compare the use of HMAs for CL determination of beef and lamb to that obtained from Soxhlet extraction technique, which is the AOAC Final Action Method for determining fat in meat and accepted as the reference method for fat determination. Additionally, the study sought to validate the use of HMAs as a method for CL determination in the Australian meat industry. Methods HMAs were used to determine the moisture content of six beef and one lamb samples, which were used to calculate the CL content. The fat content of the samples was also determined using Soxhlet fat extraction. Passing-Bablok regression and Bland-Altman plot analysis were used to identify any differences and bias between the methods, respectively. Key results Passing-Bablok regression showed that there was no difference between methods, while Bland-Altman plot analysis indicated no bias was evident between the methods. While some differences were apparent between approaches either due to using moisture as a proxy for fat/CL compared with continual solvent extraction or sample heterogeneity, sufficient agreement existed between results to lie within an acceptance criterion of 1.2 CL units. Conclusion The use of HMAs was substantiated as a method for CL determination in the Australian meat industry and has been accredited by AUS-MEAT Ltd as a method for boneless beef and lamb. Implications HMAs can be used in the Australian meat industry for CL determination and represent a relatively simpler and easier approach for this important industry metric.
12
Gardner, G. E., A. Williams, J. Siddell, A. J. Ball, S. Mortimer, R. H. Jacob, K. L. Pearce, J. E. Hocking Edwards, J. B. Rowe e D. W. Pethick. "Using Australian Sheep Breeding Values to increase lean meat yield percentage". Animal Production Science 50, n. 12 (2010): 1098. http://dx.doi.org/10.1071/an10144.
Testo completoAbstract (sommario):
This study describes the impact of Australian Sheep Breeding Values (ASBV) for post-weaning weight (PWWT), C-site fatness (PFAT) and eye muscle depth (PEMD) on lamb carcasses within the Australian Sheep Industry CRC Information Nucleus Flock. These results are taken from the 2007 drop progeny, consisting of ~2000 lambs slaughtered at a target weight of 21.5 kg. These lambs were the progeny of sires selected to ensure genetic diversity across various production traits. As expected, the PWWT ASBV increased weight at slaughter, and hot standard carcass weight. Dressing percentage was markedly improved by increasing PEMD ASBV, thus prime lamb producers will be maintaining an animal of similar weight on farm, but delivering a markedly larger carcass at slaughter. Lean meat yield % (LMY%) was highest in the progeny of sires with low PFAT ASBV, which decreased whole carcass fatness and increased muscularity. PWWT ASBV affected carcass composition but had little impact on LMY%, as the decreased fatness was largely offset by increased bone, with relatively little change in muscle content. Lastly, PEMD ASBV had little impact on whole carcass LMY%, but did appear to cause some level of muscle redistribution to the higher value loin cuts, in turn increasing the value of the carcass lean.
13
Pethick, D. W., A. J. Ball, R. G. Banks e J. F. Hocquette. "Current and future issues facing red meat quality in a competitive market and how to manage continuous improvement". Animal Production Science 51, n. 1 (2011): 13. http://dx.doi.org/10.1071/an10041.
Testo completoAbstract (sommario):
This paper discusses current and future issues facing lamb and beef meat quality and proposes strategies to manage quality improvements into the future. Based on survey data of Australian consumers and whole supply chain profit drivers, it is argued that the three most important quality areas for future research are lean meat yield, eating quality and human nutritive value. These areas have complex biological interactions, both antagonistic and complimentary, which require careful management so as to produce the best outcome for industry and the consumer. It is argued that the best way forward is to undertake collaborative research that encompasses industry production, meat science and genetics simultaneously. The case study of the Australian lamb industry is used as a suggested model for future progression, whereby a large breeding program forms the central focus of numerous research and delivery activities. Another issue raised is the need for strong and cost-effective industry systems that are able to effectively utilise outcomes from genetics, lean meat yield and eating quality to deliver the research results.
14
Mortimer, S. I., J. H. J. van der Werf, R. H. Jacob, D. W. Pethick, K. L. Pearce, R. D. Warner, G. H. Geesink et al. "Preliminary estimates of genetic parameters for carcass and meat quality traits in Australian sheep". Animal Production Science 50, n. 12 (2010): 1135. http://dx.doi.org/10.1071/an10126.
Testo completoAbstract (sommario):
Using performance from progeny born in 2007 and 2008 generated by the Information Nucleus program of the Cooperative Research Centre for Sheep Industry Innovation, preliminary estimates of heritability were obtained for a range of novel carcass and meat attributes of lamb relevant to consumers, including carcass characteristics, meat quality and nutritional value of lamb. Phenotypic and genetic correlations of live animal traits with carcass composition and meat quality traits were also estimated. The data were from progeny located at eight sites, sired by 183 rams from Merino, maternal and terminal meat breeds and were representative of the Merino, Border Leicester × Merino, Terminal × Merino and Terminal × Border Leicester-Merino production types of the Australian sheep industry. Data were available from 7176 lambs for weaning weight, 6771 lambs for ultrasound scanning and 4110 lambs for slaughter traits. For the novel meat quality traits, generally moderate to high heritability estimates were obtained for meat quality measures of shear force (0.27 aged 1 day, 0.38 aged 5 days), intramuscular fat (0.39), retail meat colour (range of 0.09 to 0.44) and myoglobin content (0.22). The nutritional value traits of omega-3 fatty acids and iron and zinc contents tended to have low to moderate heritabilities (0.11–0.37), although these were based on fewer records. Fresh meat colour traits were of low to moderate heritability (0.06–0.21) whereas measures of meat pH were of low heritability (~0.10). For the carcass traits, estimates of heritability were moderate to high for the various measures of carcass fat (0.18–0.50), muscle weight (0.22–0.35), meat yield (0.24–0.35), carcass muscle dimensions (0.25–0.34) and bone weight (0.27). Results indicate that for most lamb carcass and meat quality traits there is sufficient genetic variation for selection to alter successfully these characteristics. Additionally, most genetic correlations of live animal assessments of bodyweight, muscle and subcutaneous fat with the carcass and meat quality traits were favourable. Appropriate definition of breeding objectives and design of selection indexes should be able to account for the small unfavourable relationships that exist and achieve the desired outcomes from breeding programs.
15
Barwick, S. A., D. J. Brown, B. R. Cullis, A. K. Bell, T. J. May, M. W. Lollback, I. M. Rogan et al. "The performance of the Border Leicester in Australia". Animal Production Science 61, n. 1 (2021): 1. http://dx.doi.org/10.1071/an19493.
Testo completoAbstract (sommario):
Aims We examine the average performance of Border Leicester (BL) flocks that are part of LAMBPLAN, Australia’s sheep performance recording and genetic evaluation system. We also summarise outcomes from the New South Wales Department of Primary Industry’s research on BL improvement, and discuss the performance required for the BL to continue to be a pivotal part of the Australian prime lamb industry. Key results Modest gains have been recorded in the BL in growth since 2000 and faecal egg counts have reduced, suggesting improved worm resistance. The net reproductive rate has slightly improved, while inbreeding continues to increase. In work conducted by the New South Wales Department of Primary Industries, an improved BL flock, encompassing selection for multiple births and a broadening of the breed’s genetic base, had advantages over purebred BLs in many aspects of performance, including a 19.3% advantage in the net reproductive rate. Advantages in fertility were ~5%, litter size ~7% and lamb rearing ability ~5%. BL improved × Merino and (BL improved × BL) × Merino crossbred ewes also had advantages over traditional BL × Merino ewes in their joining performance when joined to Dorset rams. Conclusions Selection in the BL needs to emphasise traits in a manner consistent with their importance to commercial lamb production. Implications Embracing this selection and broadening the BL’s genetic base will assist the BL to maintain its place in the Australian lamb industry.
16
Pethick, D. W., R. D. Warner e R. G. Banks. "Preface: Genetic improvement of lamb—industry issues and the need for integrated research". Australian Journal of Agricultural Research 57, n. 6 (2006): 591. http://dx.doi.org/10.1071/arv57n6_pr.
Testo completoAbstract (sommario):
This paper provides an introduction to the special edition of the Australian Journal of Agricultural Research dedicated to an integrated research program to understand the effects of genetic selection for live animal traits (growth, muscle, and fatness) that determine carcass and meat attributes. Combined with this are the effects of nutritional status of the dam and growing lamb. The reasons for, and general approach of, the research is outlined.
17
Huhn, K. J., E. J. Seymour e A. M. Ridley. "Environmental Management Systems in the Australian lamb industry: challenges and opportunities for family farms". Australian Journal of Experimental Agriculture 47, n. 3 (2007): 294. http://dx.doi.org/10.1071/ea06256.
Testo completoAbstract (sommario):
An Environmental Management System (EMS) has been piloted in the Victorian lamb industry by two producer groups, one with an export focus and one with a domestic focus. We report on producers’ motivation to become involved in EMS, their current environmental performance in 15 aspects of farm management estimated through self-assessment and their experiences with an entry level EMS process. Producers were surveyed to assess motivation for participating before commencing. The results showed a major motivation was concern for the environment and an expressed ‘feeling’ of being responsible for the environmental impacts of their farming activities, both on and beyond the farm. Results from the completion of a self-assessment workbook indicate that producers on average scored well (>66%) in the management of more traditional farming aspects such as livestock and pastures and less well (<49%) in non-traditional aspects such as energy efficiency. All producers in the pilot project have progressed from self-assessment to implementing part of or a full EMS. This has provided insights into producer readiness for adoption with most supporting a staged approach and entry at a low level. We conclude that without market drivers, progress to ISO 14001 certification is not practical for most ‘small’ lamb producers. This supports the concept of a staged approach to EMS as being more achievable than immediate progress to ISO 14001 certification in the first instance because there are insufficient private benefits for most producers. We conclude that producers will need considerable extension support if EMS is to be adopted by more than a minority of producers (even the lower level approaches). Although environmentally motivated producers are likely to be interested in a Stage 2 EMS with extension support, incentives are likely to be required if the majority of producers are to embrace EMS.
18
Fogarty, N. M., D. L. Hopkins e R. van de Ven. "Lamb production from diverse genotypes. 1. Lamb growth and survival and ewe performance". Animal Science 70, n. 1 (febbraio 2000): 135–45. http://dx.doi.org/10.1017/s1357729800051675.
Testo completoAbstract (sommario):
AbstractGrowth and survival of 3673 female and cryptorchid lambs representing the range of types (second cross, first cross and Merino) produced in the Australian lamb industry are reported. The lambs were sired by a selection of Poll Dorset (D; no. = 7), Texel (T; no. = 10), Border Leicester (BL; no. = 12) and Merino (M; no. = 12) rams and born to Border Leicester × Merino (BLM) and Merino (M) dams, which resulted in six lamb genotypes (D×BLM, T×BLM, D×M, T×M, BL×M and M×M). The second cross lambs (D×BLM, T×BLM) were heavier at birth, weaning and post-weaning and had higher growth rates, than first cross lambs (D×M, T×M, BL×M), which were higher than M×M lambs (P< 0·01). For post-weaning weight (cryptorchids at 156 days) second cross lambs were 4·2 (s.e. 0·3) kg heavier than comparable sired first cross lambs, with the BL×M 2·6 (s.e. 0·5) kg lighter than other first cross types and the MxM a further 4·2 (s.e. 0·6) kg lighter. The average advantage of D over T crosses was 1·0 kg for post-weaning weight, with greater variation amongst individual sires.Lamb survival to weaning was 76% and it was affected by birth weight and birth type (P< 0·01). Sire breed had no significant effect on lamb survival, whereas lambs from BLM ewes had higher survival than those from M ewes (P< 0·01).Overall the proportion of ewes lambing was 84% with a mean litter size of 1·77. There was no difference infertility between AI (thawed frozen semen and laparoscopic insemination) and natural (single sire) mating, although the M were higher than the BLM ewes (P< 0·01). Gestation length was 2·3 days shorter (P< 0·01) for BLM than M ewes and there was no difference between D and T sire breeds. There was little effect of birth type on gestation length but it increased with birth weight within birth type categories. Between year repeatability of gestation length for ewes was 0·33 (s.e. 0·05).
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Fogarty, N. M., D. L. Hopkins e R. van de Ven. "Lamb production from diverse genotypes. 2. Carcass characteristics". Animal Science 70, n. 1 (febbraio 2000): 147–56. http://dx.doi.org/10.1017/s1357729800051687.
Testo completoAbstract (sommario):
AbstractCarcass and meat quality characteristics for 2408 cryptorchid and female lambs at mean carcass weights of 24·8 kg and 19·3 kg respectively are reported. The lambs were sired by a selection of Poll Dorset (D; no. = 7), Texel (T; no. = 10), Border Leicester (BL; no. =12) and Merino (M; no. =12) rams and born to Border Leicester × Merino (BLM) and Merino (M) dams. The lambs comprised six genotypes (D×BLM, T×BLM, D×M, T×M, BL×M and M×M) that represent the range of types (second cross, first cross and Merino) produced in the Australian lamb industry. The second cross (D×BLM, T×BLM) and first cross BL×M were fatter than first cross (D×M, T×M) (1 mm at the GR site) and M×M (3 mm GR) carcasses at the same hot carcass weight (P < 0·01). D cross were leaner than T cross for 24 kg cryptorchid carcasses at the С site (P < 0·01) but there was no difference at the GR site or f or 19 kg female carcasses at either site. There was no difference in M. longissimus thoracis et lumborum (LL) area of first cross and second cross carcasses sired by D and T rams, which were proportionately 0·04 greater than M×M and 0·09 greater than BL×M. The LL area was proportionately 0·04 greater for T than D crosses (P < 0·01). M×M had 0·02 lower dressing yield than other crosses (P < 0·01).There was a significant genotype effect for LL ultimate pH (P < 0·01). BL×M and M×M had higher mean pH and more carcasses than the other genotypes with pH greater than the critical value of 5·8 for meat quality. There were no significant differences between the genotypes for chromameter measures of meat colour. Implications for the production and processing sectors of the lamb industry are discussed.
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Vere, D. T., e G. R. Griffith. "Modifying quantitative forecasts of livestock production using expert judgments: An application to the australian lamb industry". Journal of Forecasting 14, n. 5 (settembre 1995): 453–64. http://dx.doi.org/10.1002/for.3980140505.
Testo completo
21
Friend, Michael A., Marie S. Bhanugopan, Shawn R. McGrath, Janelle Hocking Edwards, Serina Hancock, Kate Loudon, David Miller et al. "Do calcium and magnesium deficiencies in reproducing ewes contribute to high lamb mortality?" Animal Production Science 60, n. 6 (2020): 733. http://dx.doi.org/10.1071/an17588.
Testo completoAbstract (sommario):
High lamb mortality continues to be a significant economic and welfare problem within the Australian sheep industry, with 20–30% of lambs born in commercial flocks dying mostly within 3 days of birth. Clinical hypocalcaemia and hypomagnesaemia cause ewe mortality, and, subsequently, either fetal or lamb death, but it is not known whether subclinical deficiencies of calcium (Ca) and magnesium (Mg) compromise lamb survival. This review considers the potential mechanisms through which Ca and Mg deficiencies may influence lamb survival, and factors influencing the risk of deficiency. Pastures grazed by lambing ewes may be marginal in calcium (Ca; <4 g/kg DM) and magnesium (Mg; <0.9 g/kg DM) but also have a high dietary cation–anion difference (>12 meq/100 g DM) and high concentrations of potassium (K; >30 g/kg DM) and nitrogen. In young cereal crops, sodium concentrations are also often low (<0.9 g/kg DM). This combination of minerals and other nutrients creates an imbalance in supply and increases susceptibility to acute Ca (hypocalcaemia) and Mg (hypomagnesaemia) deficiency. Calcium is required for smooth muscle function and has a direct role in uterine contraction, so may influence the duration of parturition. Low Ca and Mg intake both influence insulin release and sensitivity, low Mg results in poor glycaemic control and insulin resistance by impairing both insulin secretion and its action on peripheral tissues, also potentially altering the duration of parturition as well as risk of metabolic disease. Magnesium is also a neuroprotectant that slows the neuronal damage during hypoxia and has been linked with thermogenesis in offspring and increased immunoglobulins in colostrum. These functions indicate potential importance in improving the ease of parturition and improved ability of the newborn lamb to thermoregulate and survive after birth. Subclinical Ca and Mg deficiencies commonly occur in 20% of lambing ewes grazing temperate pastures, so further studies are warranted to investigate whether correction of these deficiencies can improve lamb survival.
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Thompson, A. N., M. B. Ferguson, A. J. D. Campbell, D. J. Gordon, G. A. Kearney, C. M. Oldham e B. L. Paganoni. "Improving the nutrition of Merino ewes during pregnancy and lactation increases weaning weight and survival of progeny but does not affect their mature size". Animal Production Science 51, n. 9 (2011): 784. http://dx.doi.org/10.1071/an09139.
Testo completoAbstract (sommario):
Lamb growth to weaning, and during the period immediately following weaning, influences post-weaning mortality and may affect mature size. The hypothesis tested in the experiments reported in this paper was that changes in the maternal liveweight of Merino ewes during pregnancy and lactation could predict the weight at weaning, post-weaning survival and mature size of their progeny. At two sites (Vic. and WA) in each of two years, a wide range in the liveweight profiles of ewes was generated during pregnancy and lactation by varying the amount of supplements fed and feed on offer grazed. Across the four experiments this resulted in progeny weights ranging from 13.8 to 28.3 kg just before weaning. Lamb growth was primarily related to the amount of feed on offer during lactation, but was also related to the liveweight change of the ewe during pregnancy. These relationships were consistent in both experiments at each site. Weaning weight was strongly associated with post-weaning survival at the Vic. site. Survival rates decreased significantly when weaning weights were below 20 kg. These results indicate that management of ewe and lamb nutrition to maximise growth of lambs before weaning and growing weaners at 30 g/day or more after weaning are important for optimal post-weaning survival. The findings also suggest that the mature size of offspring is unlikely to be adversely affected by pre-weaning nutrition within the range of nutritional scenarios during pregnancy and lactation that are likely to be experienced within the Australian sheep industry.
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Ferguson, M. B., J. M. Young, G. A. Kearney, G. E. Gardner, I. R. D. Robertson e A. N. Thompson. "The value of genetic fatness in Merino ewes differs with production system and environment". Animal Production Science 50, n. 12 (2010): 1011. http://dx.doi.org/10.1071/an10130.
Testo completoAbstract (sommario):
Selection against fatness in the Australian sheep industry has been a priority, but defining the true value of fat requires an understanding of the effects it has on both the value of lamb carcasses and on sheep productivity. A Merino flock with 10 years of reproduction data was used to analyse the correlation between breeding values for fatness at yearling age (YFAT) and the number of lambs born per ewe mated (NLB). In 2 production years, NLB was related (P < 0.01) to YFAT resulting in an extra 14 or 24.5 lambs born per 100 ewes mated per mm of YFAT. Based on these relationships, bio-economic modelling was used to assess the whole-farm value of YFAT for different sheep production systems and for years representing a low, medium and high response of NLB to YFAT. The changes in whole-farm profitability for a 1-mm increase in YFAT varied from $1000 (2%) for a wool enterprise with a low response up to $44 000 (25%) for a lamb enterprise with a high response. Appropriate carcass value discounts for higher YFAT were investigated but were not evident because of the small change in GR fat depth associated with the range of YFAT investigated. In most years there is no impact of YFAT on NLB and therefore profitability, yet in years where Merino ewes with higher YFAT produce higher NLB, ewes with an extra 1 mm of YFAT will be up to 25% more profitable. Therefore, care is required in determining the appropriate selection pressure to be placed on YFAT in Merino selection.
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Hopkins, D. L., E. Safari, J. M. Thompson e C. R. Smith. "Video image analysis in the Australian meat industry – precision and accuracy of predicting lean meat yield in lamb carcasses". Meat Science 67, n. 2 (giugno 2004): 269–74. http://dx.doi.org/10.1016/j.meatsci.2003.10.015.
Testo completo
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Vallejo Adriana, Fernández Abella Daniel, Ramos Zully e Montossi Fabio. "Relationship between skin structure and wool traits for Ultrafine and Dohne Merino sheep of Uruguay". World Journal of Advanced Research and Reviews 12, n. 1 (30 ottobre 2021): 465–72. http://dx.doi.org/10.30574/wjarr.2021.12.1.0553.
Testo completoAbstract (sommario):
The demand in the world market for high quality fine and superfine wool is increasing, responding to greater wool textile industry demands and price incentives. There are few research studies focused on hair follicle population in fine and superfine Merino sheep in Uruguay. This study evaluates the association between wool follicle population and the most relevant economical wool traits. This work was carried out on Ultrafine Australian Merino (UAM) and Dohne Merino (DM) animals (lambs and rams). Phenotypic correlations between the secondary/primary follicles (S/P) and other wool traits (fiber diameter, staple length, clean fleece weight, scoured yield, coefficient of variation of fiber diameter and comfort factor parameter, were performed using histological skin cuts. Two skin samples were extracted from each lamb at two and nine months of age. These were processed at the skin histology laboratory to obtain a histological preparation for further biopsy, being able to differentiate the structures obtained to be evaluated. The results showed in the UAM group, S/P ratio in nine-month-old lambs was greater than two-month-old lambs (31.08 vs 23.12 P< 0.05). For DM group, there were no differences in the S/P ratio between age groups. Phenotypic correlations for wool characteristics obtained were of low to medium or null magnitude in both genotypes.
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Knight, M. I., H. D. Daetwyler, B. J. Hayes, M. J. Hayden, A. J. Ball, D. W. Pethick e M. B. McDonagh. "Discovery and trait association of single nucleotide polymorphisms from gene regions of influence on meat tenderness and long-chain omega-3 fatty acid content in Australian lamb". Animal Production Science 52, n. 7 (2012): 591. http://dx.doi.org/10.1071/an11229.
Testo completoAbstract (sommario):
Whole genome association studies in humans have shown a strong relationship between omega-3 levels in plasma and single nucleotide polymorphisms (SNP) located close to genes whose protein products are involved in the biosynthesis of long-chain omega-3 fatty acids. In sheep and other livestock species, the calpain/calpastatin system is the principal influence on natural variation in meat tenderness between animals. Using targeted next generation sequencing, we sequenced the fatty acid desaturase locus (FADS1/2/3), ELOVL2 and SLC26A10 and the calpain/calpastatin (CAPN1/2/3 and CAST) gene loci of 35 industry sires from the Australian flock. A total of 753 SNP were identified and 182 of these SNP were selected for incorporation onto a research SNP panel that represented the genetic variation across the nine genes. A total of 1252 animals were genotyped from the Australian Sheep CRC Information Nucleus Flock for these SNP and the genomic association was calculated for omega-3 fatty acid content and objective meat tenderness in lamb. Six SNP within CAST and CAPN2 showed association with shear force at Day 5 post-mortem at a significance level of P ≤ 0.01. When these were fitted simultaneously in a mixed-model analysis with fixed effects and covariates, three SNP remained significant. These SNP each had an unfavourable effect on shear force of between 1.1 and 1.8 N, with a combined effect of 4.1 N. The frequency of the favourable alleles in the progeny measured indicates that these SNP hold good potential for improving the management of meat tenderness across Merino, Border Leicester and Terminal sire types. No SNP within the FADS1/2/3, ELOVL2 and SLC26A10 gene regions were associated with lamb muscle omega-3 levels. This indicates that genetic variation in the long-chain omega-3 biosynthesis pathway genes analysed here may not be important for omega-3 content in lamb within the Information Nucleus Flock population.
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Warner, R. D., R. H. Jacob, J. E. Hocking Edwards, M. McDonagh, K. Pearce, G. Geesink, G. Kearney, P. Allingham, D. L. Hopkins e D. W. Pethick. "Quality of lamb meat from the Information Nucleus Flock". Animal Production Science 50, n. 12 (2010): 1123. http://dx.doi.org/10.1071/an10129.
Testo completoAbstract (sommario):
The effects of production and processing factors on tenderness, and colour of lamb meat produced from 7 locations as part of the Australian Sheep Industry CRC’s Information Nucleus flock were investigated, using data from 2052 lambs slaughtered in 2007. At 24 h post-slaughter, samples of m. longissimus lumborum (LL) and m. semimembranosus (SM) were collected for measurement of intramuscular fat (IMF), myoglobin, iron and copper and fresh meat colour (L*, a*, b*) and pH at 24 h measured on the LL. pH and temperature measurements made pre-rigor were used to calculate the pH at 18°C. Tenderness was measured by LL shear force at days 1 (SF1) and 5 (SF5) post-slaughter, the shear force difference (SF-diff) and SM compression and collagen concentration were determined. Retail colour stability was assessed using over-wrapped LL under simulated retail display for 3 days, according to the change in the oxymyoglobin/metmyoglobin ratio. All traits were affected by flock and date of slaughter (P < 0.001). After 4 days of ageing, 70–95% of the LL samples from all flocks, except for one, had acceptable tenderness for consumers based on their shear force. Low IMF, high LL pH at 18°C and high pH at 24 h increased SF1 and SF5 and also had an effect on SF-diff (P < 0.001). The retail colour of 44.8% of the samples on day 3 of retail display were lower than acceptable. Retail colour was influenced by IMF, pH18 and the concentration of iron and copper (P < 0.001). In conclusion, breeding and management practices that increase muscle IMF levels and reduce ultimate pH values and processing practices that result in moderate rates of pH fall post-slaughter, improve the tenderness of lamb. Extension of retail colour stability may be antagonistic to traits associated with tenderness and nutritional traits, particularly IMF and mineral levels.
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Fogarty, N. M., E. Safari, P. J. Taylor e W. Murray. "Genetic parameters for meat quality and carcass traits and their correlation with wool traits in Australian Merino sheep". Australian Journal of Agricultural Research 54, n. 7 (2003): 715. http://dx.doi.org/10.1071/ar03047.
Testo completoAbstract (sommario):
Estimates of genetic parameters for carcass traits in Merino sheep are presented, including muscle pH and colour, which are indicators of meat quality. The inclusion of these in the parameter set for genetic evaluation will provide the basis for more accurate estimated breeding values and the design of better breeding programs for improving meat traits in straightbred Merino sheep and crossbred lamb production. Data from 1045, nineteen-month-old Merino rams, the progeny of 125 sires from 3 strains that are representative of the industry, were used. Heritability and genetic correlations were estimated by fitting an animal model using a REML procedure in univariate and multivariate analyses. The traits included fasted pre-slaughter liveweight; dressing %; carcass tissue depth at the GR site (FATGR); fat depth at the C site (FATC); eye muscle depth (EMD), width (EMW), and area (EMA); ultimate pH and colour (L*, a*, b*) of the eye muscle. Multivariate analyses were used to estimate genetic correlations among meat traits and between wool traits (clean wool weight and mean fibre diameter) and selected carcass and meat traits. Estimates of heritability were: liveweight 0.51 (±0.10), dressing % 0.39 (±0.10), FATGR 0.33 (±0.09), FATC 0.20 (±0.08), EMD 0.27 (±0.08), EMW 0.15 (±0.07), EMA 0.23 (±0.08), muscle pH 0.27 (±0.09), and 0.14 (±0.07), 0.02 (±0.06), and 0.04 (±0.06) for the meat colour measurements L*, a*, and b* respectively. There was a favourable genetic correlation between muscle pH and colour L* of –0.56 (±0.23). There were also significant genetic correlations between wool weight and FATGR (–0.34 ± 0.16) and between mean fibre diameter and muscle colour L* (–0.66 ± 0.27). The study indicates that there is genetic variation for carcass traits, including indicators of meat quality, with scope for selection to improve meat production and quality in Merino sheep.
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Seccafien, J. E., J. M. Kelly, H. McGrice, D. O. Kleemann, K. L. Kind e W. H. E. J. van Wettere. "74 Follicular fluid anti-Müllerian hormone concentration predicts juvenile ovine in vitro embryo development". Reproduction, Fertility and Development 31, n. 1 (2019): 162. http://dx.doi.org/10.1071/rdv31n1ab74.
Testo completoAbstract (sommario):
Currently, the commercial viability of assisted reproductive embryo technologies within the Australian livestock industry is restricted by individual variability in response to treatment protocols as well as oocyte developmental competence. The majority of losses come from embryo wastage, resulting from poor developmental competence during in vitro embryo production. Follicular fluid is readily available when oocytes are collected for in vitro embryo production from juvenile or mature ewes, making it an appropriate target for analysis of phenotypic markers of oocyte developmental competence. Plasma anti-Müllerian hormone (AMH) is correlated with pregnancy losses, oocyte recovery, and blastocyst development in sheep and cattle and is an indicator for donors that respond best to gonadotrophin stimulation protocols in sheep, cattle, and goats. The aim of the current work was to determine the relationship between follicular fluid AMH and in vitro embryo production outcomes in sheep. Briefly, pairs of ovaries from 38 abattoir-derived lambs were collected individually and transferred to the laboratory. Ovaries were aspirated for in vitro embryo production following previously described methods (Walker et al. 1996 Biol. Reprod. 55, 703-708) and follicles counted. Aspirated oocytes from each of the 38 individual lamb’s pair of ovaries were pooled [n=4.11±0.53 cumulus-oocyte complexes (COC) matured/lamb; total COC matured=156], and remained as such during maturation, fertilisation, and culture. The remaining follicular fluid was centrifuged for 10min at 3000 rpm to remove excess cells and frozen at −20°C. The AMH was measured in follicular fluid by a human AMH Gen II ELISA kit validated for ovine samples (A79766, Beckman Coulter, Brea, CA, USA). Correlations between follicular fluid AMH levels and oocyte maturation and blastocyst development were determined using simple linear regression. Animals were divided into groups based on AMH levels [low (0.5-10.8ng mL−1), medium (10.81-17.89ng mL−1), or high (17.9-19.25ng mL−1)], with an unbalanced ANOVA used to determine group effects on oocyte maturation and blastocyst development (GenStat 18th edition, VSN International, Hemel Hempstead, UK). Follicular fluid AMH was positively correlated (P<0.05) with the number of follicles greater than 2mm (r2=0.120) and the proportion of COC cleaved from recovered oocytes (r2=0.134). The number of COC matured per lamb was greater for those with high and medium versus low AMH (5.6±0.97 and 4.4±0.72 versus 2.1±0.97 COC/lamb). Animals with high AMH produced more blastocysts than those with medium or low AMH, when expressed as a proportion of COC recovered (P<0.002) or cleaved (P<0.009) oocytes. High AMH was also correlated with a greater number of expanded blastocysts produced from cleaved oocytes (P<0.042). The current data support previous evidence that AMH levels positively correlate to higher antral follicle counts. The correlation between AMH and components of oocyte developmental competence suggests intrafollicular AMH may indicate the best oocytes to use for an in vitro embryo production system.
30
Granleese, T., S. A. Clark, A. A. Swan e J. H. J. van der Werf. "Increased genetic gains in multi-trait sheep indices using female reproductive technologies combined with optimal contribution selection and genomic breeding values". Animal Production Science 57, n. 10 (2017): 1984. http://dx.doi.org/10.1071/an15440.
Testo completoAbstract (sommario):
Female reproductive technologies such as multiple ovulation and embryo transfer (MOET) and juvenile in vitro fertilisation and embryo transfer (JIVET) can produce multiple offspring per mating in sheep and cattle. In breeding programs this allows for higher female selection intensity and, in the case of JIVET, a reduction in generation interval, resulting in higher rates of genetic gain. Low selection accuracy of young females entering JIVET has often dissuaded producers from using this technology. However, genomic selection (GS) could increase selection accuracy of candidates at a younger age to help increase rates of genetic gain. This increase might vary for different traits in multiple trait breeding programs depending on genetic parameters and the practicality of recording, particularly for hard to measure traits. This study used both stochastic (animals) and deterministic (GS) simulation to evaluate the effect of reproductive technologies on the genetic gain for various traits in sheep breeding programs, both with and without GS. Optimal contribution selection was used to manage inbreeding and to optimally assign reproductive technologies to individual selection candidates. Two Australian sheep industry indexes were used – a terminal sire index that focussed on growth and carcass traits (the ‘Lamb 2020’ index) and a Merino index that focuses on wool traits, bodyweight, and reproduction (MP+). We observed that breeding programs using artificial insemination or natural mating (AI/N) + MOET, compared with AI/N alone, yielded an extra 39% and 27% genetic gain for terminal and Merino indexes without GS, respectively. However, the addition of JIVET to AI/N + MOET without GS only yielded an extra 1% genetic gain for terminal index and no extra gain in the Merino index. When GS was used in breeding programs, we observed AI/N + MOET + JIVET outperformed AI/N + MOET by 21% and 33% for terminal and Merino indexes, respectively. The implementation of GS increased genetic gain where reproductive technologies were used by 9–34% in Lamb 2020 and 37–98% in MP+. Individual trait response to selection varied in each breeding program. The combination of GS and reproductive technologies allowed for greater genetic gain in both indexes especially for hard to measure traits, but had limited effect on the traits that already had a large amount of early age records.
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Geenty, K. G., F. D. Brien, G. N. Hinch, R. C. Dobos, G. Refshauge, M. McCaskill, A. J. Ball et al. "Reproductive performance in the Sheep CRC Information Nucleus using artificial insemination across different sheep-production environments in southern Australia". Animal Production Science 54, n. 6 (2014): 715. http://dx.doi.org/10.1071/an11323.
Testo completoAbstract (sommario):
The present paper covers reproductive performance in an artificial-insemination (AI) program of the Sheep CRC Information Nucleus with 24 699 lambs born at eight locations in southern Australia across five lambings between 2007 and 2011. Results from AI with frozen semen compared well with industry standards for natural mating. Conception rates averaged 72%, and 1.45 lambs were born per ewe pregnant for Merino ewes and 1.67 for crossbreds. Lamb deaths averaged 21% for Merino ewes and 15% for crossbreds and 19%, 22% and 20% for lambs from ewes that were mated to terminal, Merino and maternal sire types, respectively. Net reproductive rates were 82% for Merino ewes and 102% for crossbreds. From 3198 necropsies across 4 years, dystocia and starvation-mismothering accounted for 72% of lamb deaths within 5 days of lambing. Major risk factors for lamb mortality were birth type (single, twin or higher order), birthweight and dam breed. Losses were higher for twin and triplet lambs than for singles and there was greater mortality at relatively lighter and heavier birthweights. We conclude that reproductive rate in this AI program compared favourably with natural mating. Lamb birthweight for optimum survival was in the 4–8-kg range. Crossbred ewes had greater reproductive efficiency than did Merinos.
32
Guy, S. Z. Y., D. J. Brown e R. G. Banks. "Data capture through Australian beef cattle and meat sheep value chains: opportunities for enhanced feedback to commercial producers". Animal Production Science 58, n. 8 (2018): 1497. http://dx.doi.org/10.1071/an17807.
Testo completoAbstract (sommario):
Technologies for capturing and transmitting data from different points in livestock value chains are developing very rapidly, and interest is growing in how best to use such technologies. While new data-capture technology comes with the promise of producers and others being more informed about a system, what usually results is large and complex datasets. A key challenge is to make use of the data or information. The present paper initially outlines the data-capture points and flow of information that occurs throughout the Australian beef cattle and meat sheep value chain. The avenues through which feedback can be delivered to commercial producers are briefly summarised, along with the value of this feedback and the factors that affect its value. Finally, practical principles for effective feedback systems are provided. While data capture is occurring throughout the value chain, the main focus of the paper is on carcass- and eating-quality feedback from processors to commercial producers. There is significant variation in the volume, nature and quality of data collected, and also the flow of information among members of the chain. Further, there appears to be an inconsistency in the levels of demand or desire for the feedback. The value of feedback ultimately depends on the producer’s ability to make better business decisions as a result of having that data or information. Increasing market specifications and compliance will result in greater profitability for the producer, as well as processor. The value of feedback also depends on several other factors, including its accuracy, its granularity, whether or not it can be connected to other data, and what options the producer has to use that information in the future. Feedback must be interpretable and enable better business decisions. The value of feedback will also increase if extended further upstream along the supply chain for genetic evaluation, provided there is enough information on genetically informed animals and their identifications can be tracked across the supply chain. For efficient feedback systems, every member in the chain needs to see value in the feedback, and there needs to be a mutual commitment and shared vision between all value-chain partners. Further, feedback must be provided in an efficient and practical manner, so as to increase the willingness of the information providers to deliver the feedback. Producers should be involved in any attempts to enhance feedback systems. Since there is variability in the needs, wants and capabilities of processors and producers, multiple dynamic and flexible feedback systems are required. An incentive to enhance feedback systems is to provide a value proposition by calculating the monetary value of the feedback to all members of the chain. Better objective measurements and Meat Standards Australia for lamb is likely to also contribute to better feedback value propositions. Communication and fostering of relationships among supply-chain members will always remain critical. While data permissions add a complication to information sharing across the chain, benefits can be gained by not only the commercial producer, but the entire industry.
33
Behrendt, R., J. E. Hocking Edwards, D. Gordon, M. Hyder, M. Kelly, F. Cameron, J. Byron, M. Raeside, G. Kearney e A. N. Thompson. "Offering maternal composite ewes higher levels of nutrition from mid-pregnancy to lambing results in predictable increases in birthweight, survival and weaning weight of their lambs". Animal Production Science 59, n. 10 (2019): 1906. http://dx.doi.org/10.1071/an18505.
Testo completoAbstract (sommario):
Management of nutrition during pregnancy for maternal composite ewes has the potential to improve lamb production and survival in prime lamb production systems but existing condition score (CS) guidelines developed for Merinos may not be appropriate for the optimum production of maternal ewes. To address this, three replicated experiments were conducted at two research sites in Victoria and one in Western Australia. Ewes (781–800 per site) were allocated to four CS treatments following pregnancy scanning (~Day 50) and differentially fed to reach approximate targets of CS 2.4, 2.8, 3.2 and 3.6 by lambing. Single and multiple bearing ewes grazed together, and nutritional treatments were applied until the end of lambing after which ewes and lambs were aggregated into management groups containing all treatments. At lambing, maternal ewe liveweight had a range between treatments of 13.7–19.1 kg (average 16.4 kg) and CS varied by 1.1–1.5 of a CS (average 1.24). Across site analysis indicated that lamb birthweight and weaning weight increased with application of higher CS treatments (P < 0.001). There was also an improvement in survival of multiple born lambs with increasing CS at lambing (P < 0.001). Birthweight was significantly related to survival (P < 0.001) at all sites with no significant effect of birth type on lamb survival. Changes in birthweight and weaning weight could be predicted from ewe joining liveweight, ewe liveweight change to Day 90 and ewe liveweight change Day 90 to lambing. The coefficients derived for each of these effects were similar to those found in previous experiments examining Merino and crossbred Border Leicester Merino ewes. The optimum CS targets for multiple bearing maternal composite ewes may be higher than the industry recommended target for Merino ewes based on advantages in lamb survival and weaning weight.
34
Jacobson, C. L., K. Bell e R. B. Besier. "Nematode parasites and faecal soiling of sheep in lairage: evidence of widespread potential production losses for the sheep industry". Animal Production Science 49, n. 4 (2009): 326. http://dx.doi.org/10.1071/ea08251.
Testo completoAbstract (sommario):
Diarrhoea (scouring) and subsequent faecal soiling of fleece are important economic and welfare issues for the sheep industry. Nematode worm infections are commonly implicated as a cause of scouring. This study aimed to investigate the extent of strongyle parasite infections, and identify any association with faecal worm egg count (WEC) and scouring in sheep from winter rainfall environments in Western Australia consigned to an abattoir. Faeces were collected from sheep with evidence of scouring and normal sheep (firm faecal pellets and no evidence of fresh diarrhoea on breech). A total of 4430 sheep from 113 lines of lambs (<12 months old), 10 lines of yearlings (12–24 months old) and 235 lines of adult sheep (>24 months old) were sampled between September and January. Mean WEC in lamb lines was 1525 eggs per gram (epg) of faeces with mean WEC >1000 epg in 42% of lines and >2000 in 22% of lines. Mean WEC in adult lines was 486 epg, with 13% lines having mean WEC >1000 epg. There was a trend (P = 0.099) to higher WEC in scouring lambs (2289 epg) compared with normal lambs (1523 epg). The scouring adult sheep had lower WEC (417 epg) compared with normal adults (482 epg, P = 0.021). The findings suggest that large strongyle infections were common in lambs consigned for slaughter. The low WEC in scouring adult sheep was consistent with the suggestion that a hypersensitivity to ingested nematode larvae, rather than large worm burdens, may be responsible for scouring in mature sheep.
35
Wiese, S. C., D. W. Pethick, J. T. B. Milton, R. H. Davidson, B. L. McIntyre e D. N. D'Souza. "Effect of teeth eruption on growth performance and meat quality of sheep". Australian Journal of Experimental Agriculture 45, n. 5 (2005): 509. http://dx.doi.org/10.1071/ea03258.
Testo completoAbstract (sommario):
Two hundred and forty sheep of about 15 months of age were used in this experiment to investigate the impact of dentition category on objective and sensory meat quality. The lambs were categorised into 3 dentition classes (category 1, milk teeth; category 2, partial eruption of permanent teeth; and category 3, both permanent teeth fully erupted to the height of the central lateral milk teeth). The study was conducted on 3 farms with flocks representing the 3 genotypes that contribute to the prime lamb industry in Australia: Farm A (Merino × Merino), Farm B (first cross, Border Leicester sire × Merino ewe), and Farm C (second cross, Poll Dorset sire × Border Leicester–Merino ewe). Of the 19 meat quality attributes assessed in sheep from the 3 farms, only 1 attribute in sheep from 1 farm showed a significant deterioration in meat quality as a result of lambs progressing from dentition category 1 to 2. This was an increase in myoglobin content in lambs from Farm B (P<0.05). Many of the attributes assessed showed changes that could be considered as positive for meat quality as the lambs progressed from milk teeth to partially erupted and even to fully erupted teeth. Lambs from dentition category 3 had heavier carcass weights and higher dressing percentages compared with lambs from dentition categories 1 and 2 (P<0.05). The M. longissimus dorsi et lumborum (LD) of lambs from dentition category 3 had a lower surface lightness (L*) value, a higher myoglobin content and a lower cooking loss compared with lambs from dentition categories 1 and 2 (P<0.05). Consumer sensory assessment found the LD from lambs in dentition category 1 to have a lower acceptability score for tenderness compared with the LD from lambs in dentition category 3 (P<0.05) and a lower acceptability score for juiciness, a lower consumer rating and a lower sheep eating quality score compared with the LD from lambs in dentition categories 2 and 3 (P<0.05). The results indicate that for the range of sheep studied, meat from young sheep with partially erupted teeth is unlikely to be inferior in eating quality than the meat currently classified as lamb.
36
Hopkins, D. L. "An industry applicable model for predicting lean meat yield in lamb carcasses". Australian Journal of Experimental Agriculture 48, n. 7 (2008): 757. http://dx.doi.org/10.1071/ea07420.
Testo completoAbstract (sommario):
A wide selection of lamb types (n = 360) of mixed sex (ewes and wethers) were slaughtered at a commercial abattoir. Soft tissue depth at the GR site (thickness of tissue over the 12th rib, 110 mm from the midline) was measured in the chiller, using a GR knife (GR). Each carcass was subsequently broken down to a range of trimmed boneless retail cuts and the lean meat yield determined. The predominant industry model for predicting meat yield in Australia uses hot carcass weight (HCW) and tissue depth at the GR site. A moderate level of accuracy and precision was found when HCW and GR were used to predict lean meat yield (R2 = 40.5, r.s.d. = 2.39%), which could be improved markedly when loin muscle cross-sectional area at the 12th rib (EMA) was included in the model (R2 = 54.5, r.s.d. = 2.10%). A better result was achieved when the model included the weight of subcutaneous fat (SLFat) from the shortloin (R2 = 73.8, r.s.d. = 1.59%). A combination of SLFat and the weight of the shortloin muscle (SLMus) negated the need to include either GR or EMA in the model (R2 = 76.1, r.s.d. = 1.52%). The transportability of a model based on HCW, SLFat and SLMus was tested by randomly dividing the dataset and comparing the coefficients and the level of accuracy and precision. Collecting measures of EMA, SLFat and SLMus in boning rooms is potentially feasible. If this can be achieved under commercial conditions, a rigorous method for automatically predicting lean meat yield during boning could be applied. Application of the approach to large-scale research programs, where estimates of lean meat yield are required, would be possible at a reduced cost compared with alternative systems based on full carcass breakdown. A suitable model is given for this purpose.
37
Horn, Henrik, e Petros C. Mavroidis. "US – Lamb: United States – Safeguard Measures on Imports of Fresh, Chilled or Frozen Lamb Meat from New Zealand and Australia: What Should be Required of a Safeguard Investigation?" World Trade Review 2, S1 (2003): 72–114. http://dx.doi.org/10.1017/s1474745603001071.
Testo completoAbstract (sommario):
The United States (US) imposed, in July 1999, a safeguard on lamb meat, in the form of tariff rate import quotas, which were to be applied for a period of three years. The measure was based on findings by the US International Trade Commission that increased imports of lamb meat were a substantial cause of threat of serious injury to the US industry producing the like product. Following complaints by New Zealand and Australia that the measure was inconsistent with Articles I, II and XIX of GATT 1994, and several provisions of the Agreement on Safeguards, the World Trade Organization (WTO) Dispute Settlement Body established, in November 1999, a panel to review the consistency of the US measure with the mentioned WTO rules.
38
HORN, HENRIK, e PETROS C. MAVROIDIS. "US – Lamb United States – Safeguard Measures on Imports of Fresh, Chilled or Frozen Lamb Meat from New Zealand and Australia: what should be required of a safeguard investigation?" World Trade Review 2, n. 3 (novembre 2003): 395–430. http://dx.doi.org/10.1017/s1474745604001521.
Testo completoAbstract (sommario):
The United States (US) imposed, in July 1999, a safeguard on lamb meat, in the form of tariff rate import quotas, which were to be applied for a period of three years. The measure was based on findings by the US International Trade Commission that increased imports of lamb meat were a substantial cause of threat of serious injury to the US industry producing the like product. Following complaints by New Zealand and Australia that the measure was inconsistent with Articles I, II and XIX of GATT 1994, and several provisions of the Agreement on Safeguards, the World Trade Organization (WTO) Dispute Settlement Body established, in November 1999, a panel to review the consistency of the US measure with the mentioned WTO rules.
39
Masri, A., J. M. Macfarlane, N. Lambe, W. Haresign, E. Ruis-Vilarrasa e L. Bunger. "Comprehensive evaluation of the direct effects of LM-QTL on carcass traits in crossbred lambs". Proceedings of the British Society of Animal Science 2009 (aprile 2009): 41. http://dx.doi.org/10.1017/s1752756200028805.
Testo completoAbstract (sommario):
LoinMax (LM-QTL) increases M. longissimus dorsi (MLD) area and weight by 11% and 8% respectively (Nicoll et al., 1998). It was found to segregate in Australian Poll Dorset sheep (Banks, 1997) and has been mapped to chromosome 18 (Nicoll et al., 1998). The UK sheep industry may benefit from using LM-QTL to increase yield of the highly priced loin region. However, before being utilised, the effects of LM-QTL need to be verified in a genetic background typical to the stratified structure of the UK sheep industry.
40
Paganoni, B. L., C. M. Oldham, M. B. Ferguson, A. N. Thompson, P. E. Vercoe e D. G. Gordon. "Ewe nutrition during pregnancy and birthweight of lambs has minimal impact on fat and eye muscle depth in Merino progeny". Animal Production Science 53, n. 6 (2013): 509. http://dx.doi.org/10.1071/an12266.
Testo completoAbstract (sommario):
The hypothesis tested in this experiment was that Merino lambs with lower birthweights, due to poor ewe nutrition during pregnancy, would have more fat and less muscle than Merino lambs with higher birthweights. At two sites (Victoria and Western Australia) in each of 2 years, a wide range in the liveweight profiles of ewes was generated during pregnancy and lactation by varying the amount of supplements fed and feed on offer grazed. Progeny had fat and muscle depth at the C-site measured at various ages from 8 to 28 months of age. Across the four experiments, there were differences of 0.5 kg in birthweights and 8 kg in weaning weights between extreme treatments. The effects on the depth of fat and muscle were very small with fat depth increasing by 0.1–0.2 mm (5–7%) and muscle depth increasing by 0.2–0.7 mm (1–3%) when birthweights decreased by 1 kg. The effects of birthweight on fat depth are consistent with our hypothesis whereas the effects of birthweight on muscle depth are in contrast to our hypothesis. Nevertheless, the impacts of birthweight on the depth of fat and muscle measured at the C-site of progeny from Merino ewes, is unlikely to be of any commercial significance within the range of nutritional scenarios during pregnancy and lactation that are likely to be experienced within the Australian sheep industry.
41
Wang, Jian Tao, Guo Sen Wang, Yuan Fang Gong, Xian Qiao, Xiang Li, Gui Zhu Wang, Ying Zhen Zheng, Jian Guo Lv, Xiang Long Li e Zheng Zhu Liu. "Screening of three-way crossbred combination and genetic effect analysis of the SNP in the CLPG gene in meat sheep". Archives Animal Breeding 65, n. 4 (17 novembre 2022): 417–26. http://dx.doi.org/10.5194/aab-65-417-2022.
Testo completoAbstract (sommario):
Abstract. In order to promote the rapid development of the meat sheep industry, a three-way crossbred combination experiment was carried out with Australian White, Dorper, and Charollais sheep as terminal male parents and the elite F1 hybrids of Australian White × Small-tailed Han (Han), Dorper × Han, and Charollais × Han as female parents, which was based on the screening of a two-way crossbred combination in meat sheep. The growth performance of six groups of three-way crossbred combinations and Han lambs was measured and analyzed, and the effect of a polymorphism in the CLPG gene on the growth performance of three-way crossbred lambs was also studied. The results showed that under the same rearing conditions, weight at 3 and 6 months of age and average daily gain from birth to 3 months and from 3 to 6 months of age were all the largest for Australian × (Charollais × Han) crossbred lambs. They were significantly or extremely significant different from the other three-way crossbred combinations and Han lambs (P<0.05, P<0.01). The body height, body length, chest girth, and cannon bone circumference at 3 months of age and body length, chest girth, and cannon bone circumference at 6 months of age were also the largest for Australian × (Charollais × Han) crossbred lambs. Among them, body length, chest girth, and cannon bone circumference at 3 months of age were significantly different from the other three-way crossbred combinations and Han lambs (P<0.05), and body length, chest girth, and cannon bone circumference at 6 months of age were significantly or extremely significant different from the other three-way crossbred combinations and Han lambs (P<0.05, P<0.01). The potential genetic effects of the CLPG gene on the growth performance indicators of three-way crossbred lambs showed that a mutation site (g.232C > T) of this gene had two genotypes: CC and CT. Among them, the data of body weights and body sizes from CT genotype individuals at birth, 3 months old, and 6 months old were significantly higher than those of CC genotype individuals, and some indicators showed significant or extremely significant differences (P<0.05, P<0.01), suggesting that higher growth performance was observed in individuals with T alleles. To sum up, the crossbred combination of Australian × (Charollais × Han) could be suggested as the optimal choice. The T allele of the CLPG gene showed potential advantages in the performance of meat production in meat sheep. Based on the current results, we recommend that the offspring of Australian × (Charollais × Han) with the T allele should be preferentially utilized for meat sheep production.
42
Woodruff, Madeleine Eloise, Rebecca Doyle, Grahame Coleman, Lauren Hemsworth e Carolina Munoz. "Knowledge and attitudes are important factors in farmers’ choice of lamb tail docking length". Veterinary Record 186, n. 10 (20 gennaio 2020): 319. http://dx.doi.org/10.1136/vr.105631.
Testo completoAbstract (sommario):
BackgroundTail docking is common practice in the sheep industry to prevent soiling of the breech and flystrike. To ensure optimal healing after tail docking and reduce the risk of arthritis, perineal cancers and prolapses, it is recommended to dock tails equivalent to the length of the vulva. However, recent studies have found that some tails are docked too short (24–86 per cent).MethodsTo address this issue, this study aimed to identify key drivers behind tail docking length decisions. Two focus groups, phone (n=30) and online surveys (n=21) were conducted in regional Victoria, Australia to examine farmer knowledge of and attitudes towards appropriate lamb tail length and barriers to best practice. The focus group data were analysed qualitatively, and the surveys were analysed qualitatively and quantitatively.ResultsIn total, 57 per cent of farmers were classed as docking tails short. Short tail docking appeared to be influenced by unawareness of the recommended length and docking at a length that shearers approve of. Other potential factors included lack of knowledge of negative health consequences associated with short tails, importance placed on dag and flystrike prevention, and impracticality of measuring where to dock.ConclusionAddressing these factors in future education and intervention programmes may improve tail docking practice and sheep welfare.
43
Pitchford, WS. "Effect of crossbreeding on components of Hogget wool production". Australian Journal of Agricultural Research 43, n. 6 (1992): 1417. http://dx.doi.org/10.1071/ar9921417.
Testo completoAbstract (sommario):
Australia's prime lamb industry is based on systematic three way crossbreeding. This paper examines various genetic effects on wool production, important determinants of profitability of the meat-sheep enterprise. Data from three purebred (Merino, Corriedale and Dorset Horn), six F1 and the six three-way cross lines were analysed. Direct genetic effects were important for all traits analysed. Maternal effects were generally not important. Individual heterosis was large for clean fleece weight (13%) and hogget weight (10%) and important also for fibre diameter (2%). Maternal heterosis averaged 3% for clean fleece weight, -2% for fibre diameter, and 1% for hogget weight (5% rams; -3% ewes). These results support the hypothesis that the action of individual heterosis through increased nutrient demand results in increased mature weights. Also, the effect of maternal heterosis is to increase nutrient supply resulting in increased rates of maturation.
44
NURDJANNAH, NANAN. "PENGARUH KEPADATAN TERNA DAN LAMA PENYULINGAN TERHADAP RENDEMEN DAN KARAKTERISTIK MINYAK Melaleuca bracteata". Jurnal Penelitian Tanaman Industri 7, n. 4 (15 luglio 2020): 124. http://dx.doi.org/10.21082/jlittri.v7n4.2001.124-127.
Testo completoAbstract (sommario):
<p><strong>The influence of material bulk density and duration of distillation on the yi eld and characteristic of Melaleuca bracteata oil</strong></p><p>Melaleuca bracteata belongs to Myrtaceae family which is grown wildly in Australia and Quensland. The oil is produced from Ihe leaves and (wigs by distillation and is used in fragrances industry. The oil content of leaves and twigs range between 0.4 to 1.0% with metil eugenol as the major component (70-80%). Because of its high metil eugenol content M. bracteata oil can be used to control fruil flies The experiment was carried out to evaluate the influence of material bulk density in the distillation vessel and duration of distillation on the yield and charac¬ teristic of the oil produced. Material used was (he leaves and twigs of M bracteata from the experimental garden of the Research Institute for Spice and Medicinal Crops. Manoko, Lembang (1200 in above the sea level). The experiment at 1993 was designed as completely randomized design, arranged factorially with three replications. The result showed that the optimum distillation condition was 1 56 g/l material bulk density in the vessel and 3 hours distillation. Such distillation condition produced 1.09 % oil yield with (he characteristics as follow speciic gravity I 0263, refractive index 1 5296, optical rotation -3.3°, solubility in 70% cthanol 1 : 1, methyl eugenol content 86.1%, acid number 0.56, ester number 15.4 and ester number after acetylation 39.3. Referring to Australia oil, the Indonesian M bracteata oil has higher value of esther number both before and after acetylation.</p>
45
Kleemann, DO, RW Ponzoni, JE Stafford, IN Cutten e RJ Grimson. "Growth and carcass characters of the South Australian Merino and its crosses with the Booroola and Trangie Fertility Merino". Australian Journal of Experimental Agriculture 25, n. 4 (1985): 750. http://dx.doi.org/10.1071/ea9850750.
Testo completoAbstract (sommario):
South Australian Merino (M) and highly fecund Booroola (B) and Trangie Fertility (TF) Merino strain rams were mated to M ewes to produce M, B x M and TF x M progeny. At 4-5 months of age (24-kg slaughter group), TF x M and M lambs were heavier than B x M lambs (25.3 and 24.8 kg respectively, v. 228 kg). Similar proportional strain differences were observed at 14-1 5 months of age (38-kg slaughter group), except that, in one year, no difference was observed between the M and B x M strains, resulting in a strain x year interaction (P<0.05). When adjusted for age, TF x M carcasses were heavier than those of B x M at the first slaughter and heavier than those of B x M and M strains at the second slaughter. B x M and TF x M strains had the same fat depths and eye muscle areas, when compared at the same age, but B x M had greater fat depths and larger eye muscle areas than TF x M, relative to carcass weight; values for M were less than those of B x M and TF x M, with and without carcass weight as a covariate. Similarly, ranking of the strains did not change for carcass length, leg length and depth of thorax with and without carcass weight as a covariate. Carcasses of M lambs were longer than those of B x M, TF x M being intermediate. No differences were observed among progeny of FF and + + Booroola sires for the 12 variables measured. We conclude that carcasses of B x M and TF x M high fecundity cross Merino strains have greater depths of fat at both the same age and same carcass weight than those of the South Australian Merino, and suggest that the effect of the Booroola F gene on the characters measured is negligible. The implications of the results to the sheep industry are discussed.
46
Bateup, B. O. "Selective Scouring of Dirt from Greasy Wool". Textile Research Journal 58, n. 11 (novembre 1988): 667–72. http://dx.doi.org/10.1177/004051758805801108.
Testo completoAbstract (sommario):
Laboratory experiments using samples of eleven Australian wools representing five different classes (merino fleece, lambs, merino pieces, crossbred pieces, and pieces and bellies) showed that the dirt could be selectively removed in a warm (35 °C) suint bowl containing nonionic surfactant and alkaline builder (modified suint scouring). Removal of grease was low, and in consequence the suint bowl liquor could be readily centrifuged to give good recovery of dirt as an easily disposable spadeable sludge. In a suint bowl without additives (control), the different wools displayed two distinct modes of behavior, which could be correlated with greasy wool characteristics. The fine fleece wools gave low dirt removal; the coarser wools gave much higher dirt removal and overall recovery. Only a small amount of recoverable grease was removed. This difference in the behavior of different wools may explain the varying ideas about the effectiveness of suint bowls in industry and provides an opportunity to improve the overall efficiency of the scouring operation.
47
Siddell, J., B. M. McLeod, E. S. Toohey, R. van de Ven e D. L. Hopkins. "The prediction of meat yield in lamb carcasses using primal cut weights, carcass measures and the Hennessy Grading Probe". Animal Production Science 52, n. 7 (2012): 584. http://dx.doi.org/10.1071/an11260.
Testo completoAbstract (sommario):
A wide selection of crossbred lambs (n = 268) of mixed sex (ewes and wethers) were slaughtered at a commercial abattoir. Tissue depth at the GR site (thickness of tissue over the 12th rib 110 mm from the midline) was measured in the chiller using a GR knife (GR) and fatscore (1–5) was assessed on each carcass by abattoir personnel. Each carcass was subsequently broken down to a range of trimmed cuts (subprimals) and the meat yield in kilograms determined as the sum of the weights of these cuts. The best model for the prediction of meat yield was based on the weight of the 4-rib, untrimmed forequarter, fatscore and GR, which had a mean-squared prediction error of 0.96, but a simpler model based on weight of the forequarter and GR only had a marginally higher mean-squared prediction error at 0.97. In both models as either forequarter weight, GR or fatscore increased the meat yield increased. The predominant industry model for predicting meat yield in Australia uses carcass weight and tissue depth at the GR site, but these predictors were less useful than models based on forequarter weight. There was no significant improvement for the prediction of meat yield from the use of muscle or fat depths measured with a Hennessy Grading Probe or directly on the carcass with a ruler when a subset of 97 carcasses was examined. In this case the final model was based on the weight of the forequarter and the weight of the hind leg (R2 = 95%). It is feasible to collect the weight of the forequarter before subprimal cut preparation and if this can be achieved under commercial conditions, a method for predicting meat yield automatically during this procedure could be applied.
48
Pearce, K. L., D. G. Masters, R. H. Jacob, D. L. Hopkins e D. W. Pethick. "Effects of sodium chloride and betaine on hydration status of lambs at slaughter". Australian Journal of Experimental Agriculture 48, n. 9 (2008): 1194. http://dx.doi.org/10.1071/ea08034.
Testo completoAbstract (sommario):
Under commercial conditions in Australia, lambs are often dehydrated at slaughter despite access to water at the abattoir. Dehydration results in reduced fluid content of meat, which causes liveweight and carcass weight loss. Two experiments evaluated hydration status and carcass characteristics in lambs fed increased levels of sodium chloride (salt) and/or betaine before slaughter. Both experiments were 2 × 2 factorial designs with two levels of salt added [0 and 50 g/kg dry matter (DM)] and two levels of betaine added (0 and 6.7 g/kg DM) to the diets. The treatment diets were introduced to sheep over a 7–8-day period and then fed at 1.5 kg/day for the following 7 days. In experiment 1, 96 Poll Dorset–Merino cross wether lambs (45.9 ± 0.17 kg) were fed in individual pens and in experiment 2, 204 Merino wether lambs (43.1 ± 0.35 kg) were fed in group pens. In the first experiment, water and feed were withheld from the end of the treatment feeding period until slaughter 48 h later. In the second experiment, feed and water were withheld for the first 24 h after treatment but water was available for the next 24 h immediately before slaughter. In both experiments, consumption of the high salt diet decreased urine specific gravity and osmolarity at the end of the feeding period and after 24 h without access to water. This indicates an improved hydration status at this time. However, the difference in hydration status related to feeding salt declined during the 48-h lairage period and there were no significant differences in hot carcass weight or muscle DM among groups at slaughter. It could be concluded from this result that the addition of salt has little commercial value; however, this may not be the case. The lambs in experiment 2 did not behave according to industry expectations. They all drank water in the last 24 h in lairage and none of the groups showed severe dehydration. Further research is justified to determine if the lambs fed the diets with no added salt drunk in lairage as a learned response from the lambs fed salt and, if so, whether this can be developed into a commercial strategy. Feeding betaine did not result in any changes in hydration status or carcass characteristics.
49
Ihsan, Muhsinul, Bayu Priyambodo e Handa Muliasari. "Pelatihan pembuatan pakan gel berbasis bahan lokal sebagai pakan alternatif budidaya lobster di Pulau Lombok". Transformasi: Jurnal Pengabdian Masyarakat 16, n. 1 (30 giugno 2020): 1–11. http://dx.doi.org/10.20414/transformasi.v16i1.2106.
Testo completoAbstract (sommario):
[Bahasa]: Komponen biaya terbesar dari usaha budidaya lobster adalah pakan. Pakan buatan diyakini merupakan salah satu solusi berkelanjutan bagi pengembangan industri budidaya yang ramah lingkungan. Dengan demikian, inovasi formulasi dan pembuatan pakan buatan harus terus dilakukan. Tujuan pengabdian ini adalah untuk memberikan keterampilan kepada pembudidaya lobster untuk memproduksi pakan buatan berbentuk gel berbasis bahan lokal di Dusun Telong-Elong Jerowaru Lombok Timur. Metode yang digunakan adalah Participatory Action Research (PAR). Peserta pelatihan menginisiasi, menyiapkan, dan mempraktekkan langsung cara pembuatan pakan dengan dibimbing oleh pengabdi. Evaluasi pakan yang dihasilkan meliputi tiga hal yaitu: tekstur (kelenturan), attractabilty (daya tarik), dan water stability (ketahanan dalam air). Melalui pelatihan yang difasilitasi oleh Australian Center for International Agricultural Research (ACIAR), pembudidaya berhasil memproduksi pakan buatan dengan karakteristik sebagai berikut: tekstur pakan yang dihasilkan menyerupai tekstur daging udang; daya tarik pakan sangat bagus; dan pakan mampu tidak hancur di dalam air selama 24 jam sebelum dimakan oleh lobster. Kelemahan pakan yang dihasilkan adalah tidak bisa bertahan lama ketika dimastikasi oleh lobster. Hal ini menyebabkan sebagian nutrien dalam pakan larut dalam air. Secara umum, pakan yang dihasilkan telah memenuhi sebagian besar kriteria yang diperlukan bagi pakan buatan lobster. Kombinasi binder perlu dikaji ulang untuk mengatasi kelemahan dalam pakan.
Kata Kunci: pelatihan, pakan buatan, lobster, budidaya
[English]: The major cost of lobster aquaculture is in the feed. The artificial feed is one of the viable solutions for development of aquaculture industry as it is environmentally friendly. Therefore, the innovation in formulating and producing the artificial feed shall be pursued. The purpose of this community service program is to equip the lobster farmers with the skills in producing artificial feed using local ingredients in Lombok Island. Participatory Action Research (PAR) method was used in this program. The participants initiated, prepared, and practiced the skills directly guided by the trainers. Artificial feeds produced by the participants were then evaluated including the texture, attractability, and water stability. Through this training facilitated by the Australian Center for International Agricultural Research (ACIAR), lobster farmers succeeded in producing artificial feed with the characteristics: the texture is similar to the texture of shrimp meat, the attractability is very good, and cannot be destroyed in water for 24 hours before being eaten by lobsters. The disadvantage of artificial feed is that it is unstable when masticatied and eaten by lobsters. This cause some of nutrients in the feed dissolve in water. In general, the artificial feed produced by lobster farmers have fulfilled the criteria of lobster feed. Binder combination is need to be reviewed to overcome weakness in artificial feed.
Keywords: training, artificial feed, lobster, aquaculture
50
Sinambela, D. P., D. Bakti, M. C. Tobing e Y. M. Kusumah. "Molecular characterization of Spodoptera litura Nucleopolyhedrovirus (SlNPV) Labuhan Batu isolate". IOP Conference Series: Earth and Environmental Science 974, n. 1 (1 gennaio 2022): 012011. http://dx.doi.org/10.1088/1755-1315/974/1/012011.
Testo completoAbstract (sommario):
Abstract Spodoptera litura F. is a new pest that potentially becomes a serious pest threatening palm oil industry. The control can be carried out using biological control agents S.litura Nucleopolyhedrovirus (SlNPV). Molecular approach using polymerase chain reaction (PCR) has been used to characterize the SlNPV isolate. The aim of this study was to determine the molecular characteristics of SlNPV Labuhan Batu isolate based on DNA sequence analysis. The NPV isolate was collected from oil palm plantation Negeri Lama Estate Group, PT. Hari sawit Jaya, Asian Agri, Labuhan Batu. The SlNPV DNA extraction was conducted using the DNA gSYNC kit. The amplification of SlNPV DNA was done by specific primers with oligonucleotide sequences forward 5′-ACGTTACGATCTAGATCC-3′ and reverse 5′-AACGTTAGACAGACATAT-3′ with ±700bp of amplicon. Homology and phylogeny characteristics were used to determine the relationship of SlNPV isolate from Labuhan Batu to NPV from other countries were reported in the GeneBank of National Center for Biotechnology Information (NCBI). The results showed that SlNPV isolate from Labuhan Batu had the closest related to SlNPV from Australia, SliNPV from Canada and SlNPV from China, with the similarity percentage 100%, 96% and 90% respectively. They belong to the same group as the NPVs that infected the Spodoptera genus.