A total of 7622 cattle were measured for several weight and body composition traits in temperate ... more A total of 7622 cattle were measured for several weight and body composition traits in temperate and tropically adapted breeds. Traits included: liveweight, hip height, body fat score, muscle score, flight time, ultrasound scanned fatness, and eye muscle area. Measurements were taken at 3 stages during the project: post-weaning, start of finishing, and end of finishing (i.e. pre-slaughter). Animals were finished to 3 target market-weight end-points (220, 280, or 340 kg carcass weight), either on pasture or in a feedlot, and in 2 different geographic regions for tropically adapted breeds. These data were used to estimate genetic parameters for the traits at each stage, and also to estimate the effect of market weight and finishing regimes on the phenotypic and genetic expression of each trait measured at the end of finishing stage. Results showed, for all traits, that the magnitude of the phenotypic expression increased across the stages and market-weight end-points for the end of fi...
The Cooperative Research Centre (CRC) for Beef Genetic Technologies was developed in partnership ... more The Cooperative Research Centre (CRC) for Beef Genetic Technologies was developed in partnership by the Australian beef industry (Cattle Council of Australia, Meat and Livestock Australia, Australian Lot Feeders' Association, corporate and individual beef producers) and prestigious national and international scientific institutions over 2003 and 2004. It is a collaborative venture between 19 partner organizations from Australia, New Zealand, Korea and the USA, with associate partners from Northern Ireland, the Irish Republic, France and South Africa. It focuses on four beef industry priority issues (high quality beef, feed efficiency, disease resistance and improved reproductive performance) to capture unique opportunities for Australia through world-class gene discovery and gene expression research and accelerated adoption of beef industry technologies to improve profitability, productivity, animal welfare and responsible resource use of Australian beef businesses. The Centre c...
... Final Report: Developing profitable beef business systems for previously disadvantaged farmer... more ... Final Report: Developing profitable beef business systems for previously disadvantaged farmers in South Africa ... 1997) identified five main characteristics of an effective cattle breeding strategy aimed at delivering benefits to small-scale cattle owners in developing countries. ...
Separate experiments were conducted in 2 zebu-derived herds grazed at pasture in the dry tropics ... more Separate experiments were conducted in 2 zebu-derived herds grazed at pasture in the dry tropics of Central Queensland, to determine genetic and environmental effects on At Duckponds, temperament of crossbreed steers and heifers from 2 calf crops was assessed using an objective flight speed score and 2 subjective scores (a visual flight speed score and a crush score) to determine whether the subjective tests were useful as selection criteria for on-farm selection programs. At Belmont, temperament of bull and heifer calves from 7 calf crops was measured by recording objective flight speed scores of individual animals at weaning (6 months), 12 months, and 18 months. At Duckponds, heritabilities of average objective flight speed, visual flight speed, and crush scores were 0.35, 0.08, and 0.30, respectively. Phenotypic and genetic correlations between the different measures of temperament were moderate to low. Based on low correlations and re-ranking of fixed effect classes that occurre...
... Using an AM for growth traits and scrotal sizes ignores the contribution of maternal genetic ... more ... Using an AM for growth traits and scrotal sizes ignores the contribution of maternal genetic effects to these traits. However, Meyer (1994) suggested that ignoring maternal effects for such traits was unlikely to substantially bias the covariance estimates. ...
This paper examines the relative importance of productive and adaptive traits in beef breeding sy... more This paper examines the relative importance of productive and adaptive traits in beef breeding systems based on Bos taurus and tropically adapted breeds across temperate and (sub)tropical environments. In the (sub)tropics, differences that exist between breeds in temperate environments are masked by the effects of environmental stressors. Hence in tropical environments, breeds are best categorised into breed types to compare their performance across environments. Because of the presence of environmental stressors, there are more sources of genetic variation in tropical breeding programmes. It is therefore necessary to examine the genetic basis of productive and adaptive traits for breeding programmes in those environments. This paper reviews the heritabilities and genetic relationships between economically important productive and adaptive traits relevant to (sub)tropical breeding programmes. It is concluded that it is possible to simultaneously genetically improve productive and adaptive traits in tropically adapted breeds of beef cattle grazed in tropical environments without serious detrimental consequences for either adaptation or production. However, breed-specific parameters are required for genetic evaluations. The paper also reviews the magnitude of genotype × environment (G × E) interactions impacting on production and adaptation of cattle, where 'genotype' is defined as breed (within a crossbreeding system), sire within breed (in a within-breed selection programme) or associations between economically important traits and single nucleotide polymorphisms (SNPs - within a marker-assisted selection programme). It is concluded that re-ranking of breeds across environments is best managed by the use of the breed type(s) best suited to the particular production environment. Re-ranking of sires across environments is apparent in poorly adapted breed types across extreme tropical and temperate environments or where breeding animals are selected in a temperate environment for use in the (sub)tropics. However, G × E interactions are unlikely to be of major importance in tropically adapted beef cattle grazed in either temperate or (sub)tropical environments, although sex × environment interactions may provide new opportunities for differentially selecting to simultaneously improve steer performance in benign environments and female performance in harsher environments. Early evidence suggests that re-ranking of SNPs occurs across temperate and tropical environments, although their magnitude is still to be confirmed in well-designed experiments. The major limitation to genetic improvement of beef cattle over the next decade is likely to be a deficiency of large numbers of accurately recorded phenotypes for most productive and adaptive traits and, in particular, for difficult-to-measure adaptive traits such as resistance to disease and environmental stressors.
The Cooperative Research Centre (CRC) for Beef Genetic Technologies operated for its third succes... more The Cooperative Research Centre (CRC) for Beef Genetic Technologies operated for its third successive 7-year term from July 2005 to June 2012. It targeted an additional 1.5 per cent in gross revenue of the Australian beef industry over 25 years to 2030. This was to be achieved by developing a package of new genetic and genomic technologies and non-genetic " products " (practices, processes, tools and technologies) to improve profitability, productivity, animal welfare and responsible resource use of Australian beef businesses. The economic analyses underpinning the 2004 business case for the CRC's third term were published by Griffith et al. (2005) and Griffith (2009). In reassessing the original estimates of economic benefit as at the end of the CRC investment phase, the most prominent issues to consider were the potential total productivity growth available to the beef and cattle industries as a result of CRC technologies, how each research program contributed to the...
The Cooperative Research Centre (CRC) for Beef Genetic Technologies operated for its third succes... more The Cooperative Research Centre (CRC) for Beef Genetic Technologies operated for its third successive 7-year term from July 2005 to June 2012. It developed new genetic and genomic technologies and non-genetic 'products' (practices, processes, tools and technologies) to improve profitability, productivity, animal welfare and responsible resource use of Australian beef businesses. In this paper we assess how well the third-term Beef CRC met its objectives, at the end of its funding period, using the Impact Tool software package developed by the CRC Program of the Commonwealth Government. The Impact Tool generates two commonly used measures of return on investment: the net present value (NPV) and the benefit : cost ratio (BCR). The NPV, the sum of discounted benefits minus the sum of discounted costs, was $ 233.2 m, when evaluated over the period 2005/06-2020/21. The BCR, the sum of discounted benefits divided by the sum of discounted costs, was 2.94, over the same period. Thus...
Diagnostic histopathology / published in association with the Pathological Society of Great Britain and Ireland
The glucocorticoid binding properties of 18 human lymphoid cell lines (HLCL) have been investigat... more The glucocorticoid binding properties of 18 human lymphoid cell lines (HLCL) have been investigated. The specificity of steroid binding was confirmed with various glucocorticoid agonists and antagonists. A gradation in whole cell and cytoplasmic glucocorticoid binding capacity was observed in the different cell line types: lymphoblastoid greater than lymphoma greater than leukaemia. The cytoplasmic receptors of leukaemia and lymphoblastoid lines appeared to contain both proteinaceous and phospholipid components. Cytoplasmic steroid-receptor complexes exhibited a wide range of sedimentation coefficients (8.5-11.3S) in low ionic strength buffer but there was no correlation with cell line type or glucocorticoid sensitivity. Activation of these complexes by heat (37 degrees C) or exposure to high ionic strength buffer (0.3 M NaCl) induced nuclear binding of steroid but only complexes in high ionic strength buffer manifested changes in sedimentation coefficient. No correlation was observ...
The glucocorticoid binding properties and cytolethal responsiveness of leukaemic cells were studi... more The glucocorticoid binding properties and cytolethal responsiveness of leukaemic cells were studied in vitro in seven patients with hairy-cell leukaemia (HCL) and five with chronic lymphocytic leukaemia (CLL). Substantial levels of glucocorticoid binding were detected both in whole cell and cytosol preparations from all patients although the level of binding by HCL cells always exceeded that of CLL cells (P less than 0.05). In both leukaemic cell types the uptake and binding of prednisolone in vitro was significantly greater than that of dexamethasone (P less than 0.05). CLL cells showed a variable dose-related cytolethal response to methylprednisolone sodium succinate (MPSS) treatment in vitro although cytolytic effects were not marked in the usual pharmacological dose range (10(-5)-10(-6)M). Treatment of CLL patients with conventional doses of prednisone for extended periods or high intravenous infusions of MPSS over shorter periods had no consistent effect on the in-vitro level of steroid binding or the cytolethal responsiveness of CLL cells to glucocorticoid treatment. Although HCL cells proved highly resistant to the cytolethal effects of MPSS in vitro, the substantial binding of glucocorticoids by leukaemic cells from all HCL patients indicates the potential value of steroid therapy in this disease should be explored further.
The Cooperative Research Centre (CRC) for the Cattle and Beef Industry (Meat Quality) developed a... more The Cooperative Research Centre (CRC) for the Cattle and Beef Industry (Meat Quality) developed an integrated research program to address the major production and processing factors affecting beef quality. Underpinning the integrated program were 2 large-scale progeny testing programs that were used to develop genetic, nutritional, management and beef processing technologies to overcome deficiencies in beef quality. This paper describes the experimental design, generation of experimental cattle and the collection and storage of data derived from these straightbreeding and crossbreeding progeny testing programs.
Two experiments measured the ability of tropically adapted beef breeds from resource-poor farmer ... more Two experiments measured the ability of tropically adapted beef breeds from resource-poor farmer herds in South Africa to produce high quality beef under commercial feedlot conditions. The resource-poor farming sector consists of 'emerging' and communal farmers. The herd and breed groups consisted of Sanga types (tropically adapted Bos taurus breed) including Nguni, Tuli, Bonsmara and Drakensberger, as well as Brahman and non-descript groups. The cattle were slaughtered after an average of 97 days in the first experiment and after an average of 92, 140 and 169 days on a grain-based diet in the second experiment. Growth performance, carcass quality and yield, occurrence of disease and meat quality were measured. The performance of the breeds groups was a function of their genetic potential and herd type (carcass weight and condition at ar rival). Steers from emerging and communal farmer herds enter the feedlot at a lighter weight, but show similar growth performance to achiev...
A total of 7622 cattle were measured for several weight and body composition traits in temperate ... more A total of 7622 cattle were measured for several weight and body composition traits in temperate and tropically adapted breeds. Traits included: liveweight, hip height, body fat score, muscle score, flight time, ultrasound scanned fatness, and eye muscle area. Measurements were taken at 3 stages during the project: post-weaning, start of finishing, and end of finishing (i.e. pre-slaughter). Animals were finished to 3 target market-weight end-points (220, 280, or 340 kg carcass weight), either on pasture or in a feedlot, and in 2 different geographic regions for tropically adapted breeds. These data were used to estimate genetic parameters for the traits at each stage, and also to estimate the effect of market weight and finishing regimes on the phenotypic and genetic expression of each trait measured at the end of finishing stage. Results showed, for all traits, that the magnitude of the phenotypic expression increased across the stages and market-weight end-points for the end of fi...
The Cooperative Research Centre (CRC) for Beef Genetic Technologies was developed in partnership ... more The Cooperative Research Centre (CRC) for Beef Genetic Technologies was developed in partnership by the Australian beef industry (Cattle Council of Australia, Meat and Livestock Australia, Australian Lot Feeders' Association, corporate and individual beef producers) and prestigious national and international scientific institutions over 2003 and 2004. It is a collaborative venture between 19 partner organizations from Australia, New Zealand, Korea and the USA, with associate partners from Northern Ireland, the Irish Republic, France and South Africa. It focuses on four beef industry priority issues (high quality beef, feed efficiency, disease resistance and improved reproductive performance) to capture unique opportunities for Australia through world-class gene discovery and gene expression research and accelerated adoption of beef industry technologies to improve profitability, productivity, animal welfare and responsible resource use of Australian beef businesses. The Centre c...
... Final Report: Developing profitable beef business systems for previously disadvantaged farmer... more ... Final Report: Developing profitable beef business systems for previously disadvantaged farmers in South Africa ... 1997) identified five main characteristics of an effective cattle breeding strategy aimed at delivering benefits to small-scale cattle owners in developing countries. ...
Separate experiments were conducted in 2 zebu-derived herds grazed at pasture in the dry tropics ... more Separate experiments were conducted in 2 zebu-derived herds grazed at pasture in the dry tropics of Central Queensland, to determine genetic and environmental effects on At Duckponds, temperament of crossbreed steers and heifers from 2 calf crops was assessed using an objective flight speed score and 2 subjective scores (a visual flight speed score and a crush score) to determine whether the subjective tests were useful as selection criteria for on-farm selection programs. At Belmont, temperament of bull and heifer calves from 7 calf crops was measured by recording objective flight speed scores of individual animals at weaning (6 months), 12 months, and 18 months. At Duckponds, heritabilities of average objective flight speed, visual flight speed, and crush scores were 0.35, 0.08, and 0.30, respectively. Phenotypic and genetic correlations between the different measures of temperament were moderate to low. Based on low correlations and re-ranking of fixed effect classes that occurre...
... Using an AM for growth traits and scrotal sizes ignores the contribution of maternal genetic ... more ... Using an AM for growth traits and scrotal sizes ignores the contribution of maternal genetic effects to these traits. However, Meyer (1994) suggested that ignoring maternal effects for such traits was unlikely to substantially bias the covariance estimates. ...
This paper examines the relative importance of productive and adaptive traits in beef breeding sy... more This paper examines the relative importance of productive and adaptive traits in beef breeding systems based on Bos taurus and tropically adapted breeds across temperate and (sub)tropical environments. In the (sub)tropics, differences that exist between breeds in temperate environments are masked by the effects of environmental stressors. Hence in tropical environments, breeds are best categorised into breed types to compare their performance across environments. Because of the presence of environmental stressors, there are more sources of genetic variation in tropical breeding programmes. It is therefore necessary to examine the genetic basis of productive and adaptive traits for breeding programmes in those environments. This paper reviews the heritabilities and genetic relationships between economically important productive and adaptive traits relevant to (sub)tropical breeding programmes. It is concluded that it is possible to simultaneously genetically improve productive and adaptive traits in tropically adapted breeds of beef cattle grazed in tropical environments without serious detrimental consequences for either adaptation or production. However, breed-specific parameters are required for genetic evaluations. The paper also reviews the magnitude of genotype × environment (G × E) interactions impacting on production and adaptation of cattle, where 'genotype' is defined as breed (within a crossbreeding system), sire within breed (in a within-breed selection programme) or associations between economically important traits and single nucleotide polymorphisms (SNPs - within a marker-assisted selection programme). It is concluded that re-ranking of breeds across environments is best managed by the use of the breed type(s) best suited to the particular production environment. Re-ranking of sires across environments is apparent in poorly adapted breed types across extreme tropical and temperate environments or where breeding animals are selected in a temperate environment for use in the (sub)tropics. However, G × E interactions are unlikely to be of major importance in tropically adapted beef cattle grazed in either temperate or (sub)tropical environments, although sex × environment interactions may provide new opportunities for differentially selecting to simultaneously improve steer performance in benign environments and female performance in harsher environments. Early evidence suggests that re-ranking of SNPs occurs across temperate and tropical environments, although their magnitude is still to be confirmed in well-designed experiments. The major limitation to genetic improvement of beef cattle over the next decade is likely to be a deficiency of large numbers of accurately recorded phenotypes for most productive and adaptive traits and, in particular, for difficult-to-measure adaptive traits such as resistance to disease and environmental stressors.
The Cooperative Research Centre (CRC) for Beef Genetic Technologies operated for its third succes... more The Cooperative Research Centre (CRC) for Beef Genetic Technologies operated for its third successive 7-year term from July 2005 to June 2012. It targeted an additional 1.5 per cent in gross revenue of the Australian beef industry over 25 years to 2030. This was to be achieved by developing a package of new genetic and genomic technologies and non-genetic " products " (practices, processes, tools and technologies) to improve profitability, productivity, animal welfare and responsible resource use of Australian beef businesses. The economic analyses underpinning the 2004 business case for the CRC's third term were published by Griffith et al. (2005) and Griffith (2009). In reassessing the original estimates of economic benefit as at the end of the CRC investment phase, the most prominent issues to consider were the potential total productivity growth available to the beef and cattle industries as a result of CRC technologies, how each research program contributed to the...
The Cooperative Research Centre (CRC) for Beef Genetic Technologies operated for its third succes... more The Cooperative Research Centre (CRC) for Beef Genetic Technologies operated for its third successive 7-year term from July 2005 to June 2012. It developed new genetic and genomic technologies and non-genetic 'products' (practices, processes, tools and technologies) to improve profitability, productivity, animal welfare and responsible resource use of Australian beef businesses. In this paper we assess how well the third-term Beef CRC met its objectives, at the end of its funding period, using the Impact Tool software package developed by the CRC Program of the Commonwealth Government. The Impact Tool generates two commonly used measures of return on investment: the net present value (NPV) and the benefit : cost ratio (BCR). The NPV, the sum of discounted benefits minus the sum of discounted costs, was $ 233.2 m, when evaluated over the period 2005/06-2020/21. The BCR, the sum of discounted benefits divided by the sum of discounted costs, was 2.94, over the same period. Thus...
Diagnostic histopathology / published in association with the Pathological Society of Great Britain and Ireland
The glucocorticoid binding properties of 18 human lymphoid cell lines (HLCL) have been investigat... more The glucocorticoid binding properties of 18 human lymphoid cell lines (HLCL) have been investigated. The specificity of steroid binding was confirmed with various glucocorticoid agonists and antagonists. A gradation in whole cell and cytoplasmic glucocorticoid binding capacity was observed in the different cell line types: lymphoblastoid greater than lymphoma greater than leukaemia. The cytoplasmic receptors of leukaemia and lymphoblastoid lines appeared to contain both proteinaceous and phospholipid components. Cytoplasmic steroid-receptor complexes exhibited a wide range of sedimentation coefficients (8.5-11.3S) in low ionic strength buffer but there was no correlation with cell line type or glucocorticoid sensitivity. Activation of these complexes by heat (37 degrees C) or exposure to high ionic strength buffer (0.3 M NaCl) induced nuclear binding of steroid but only complexes in high ionic strength buffer manifested changes in sedimentation coefficient. No correlation was observ...
The glucocorticoid binding properties and cytolethal responsiveness of leukaemic cells were studi... more The glucocorticoid binding properties and cytolethal responsiveness of leukaemic cells were studied in vitro in seven patients with hairy-cell leukaemia (HCL) and five with chronic lymphocytic leukaemia (CLL). Substantial levels of glucocorticoid binding were detected both in whole cell and cytosol preparations from all patients although the level of binding by HCL cells always exceeded that of CLL cells (P less than 0.05). In both leukaemic cell types the uptake and binding of prednisolone in vitro was significantly greater than that of dexamethasone (P less than 0.05). CLL cells showed a variable dose-related cytolethal response to methylprednisolone sodium succinate (MPSS) treatment in vitro although cytolytic effects were not marked in the usual pharmacological dose range (10(-5)-10(-6)M). Treatment of CLL patients with conventional doses of prednisone for extended periods or high intravenous infusions of MPSS over shorter periods had no consistent effect on the in-vitro level of steroid binding or the cytolethal responsiveness of CLL cells to glucocorticoid treatment. Although HCL cells proved highly resistant to the cytolethal effects of MPSS in vitro, the substantial binding of glucocorticoids by leukaemic cells from all HCL patients indicates the potential value of steroid therapy in this disease should be explored further.
The Cooperative Research Centre (CRC) for the Cattle and Beef Industry (Meat Quality) developed a... more The Cooperative Research Centre (CRC) for the Cattle and Beef Industry (Meat Quality) developed an integrated research program to address the major production and processing factors affecting beef quality. Underpinning the integrated program were 2 large-scale progeny testing programs that were used to develop genetic, nutritional, management and beef processing technologies to overcome deficiencies in beef quality. This paper describes the experimental design, generation of experimental cattle and the collection and storage of data derived from these straightbreeding and crossbreeding progeny testing programs.
Two experiments measured the ability of tropically adapted beef breeds from resource-poor farmer ... more Two experiments measured the ability of tropically adapted beef breeds from resource-poor farmer herds in South Africa to produce high quality beef under commercial feedlot conditions. The resource-poor farming sector consists of 'emerging' and communal farmers. The herd and breed groups consisted of Sanga types (tropically adapted Bos taurus breed) including Nguni, Tuli, Bonsmara and Drakensberger, as well as Brahman and non-descript groups. The cattle were slaughtered after an average of 97 days in the first experiment and after an average of 92, 140 and 169 days on a grain-based diet in the second experiment. Growth performance, carcass quality and yield, occurrence of disease and meat quality were measured. The performance of the breeds groups was a function of their genetic potential and herd type (carcass weight and condition at ar rival). Steers from emerging and communal farmer herds enter the feedlot at a lighter weight, but show similar growth performance to achiev...
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