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A report is made of molding runs on grommet no. 9270722 listed under Government Contract No. DAAA21-74-C-0460.

All organisms are subject to mutations as a result of normal cellular operations or interactions with the environment, leading to genetic variation (polymorphism). In conjunction with selection and genetic drift, there arises genetic variation within and among individuals and species. For this variation to be useful to geneticists, it must be heritable and discernable whether as a recognisable phenotypic variation or as a genetic mutation distinguishable through molecular techniques. PCR amplification and gel electrophoresis resolution of products using RAPD primer A2 shows polymorphism of up to 5 bands was evident. It also demonstrates that at the molecular level, there are banding differences that can be picked up between crossbred progeny sired by rams with high genetic merit for growth or muscle.Fat depth at the GR and C sites was significantly (P<0.05) influenced by level of nutrition and nutrition level x siretype interaction in that fat depths were greater in crossbred lambs fed at high levels of nutrition than those fed low nutrition levels. Lambs selected for growth and fed high level of nutrition produced carcasses with the least KNIFE GR fat depth of 11.4mm, a significant reduction from 18.1mm in the control group fed low level nutrition.

This study utilized leaf stage-based defoliation intervals to describe the concentrations and contents of watersoluble carbohydrate (WSC) and nitrogen (N) in stubble and root reserves and their effect on the regrowth of prairie grass (Bromus willdenowii Kunth.) plants. The priority sequence for allocation of WSC reserves during the regrowth period was also investigated. There were substantially higher concentrations of WSC and N in the stubble compared with the roots following defoliation, confirming the stubble as the primary site for energy storage, with roots playing a lesser role. However, high R2 values for the relationships between WSC concentration in roots and regrowth variables suggested that plants of prairie grass were reliant on WSC reserves from the roots in addition to the stubble to meet the energy requirements of plants until adequate photosynthetic tissue had been produced. The sequence of priority for allocation of WSC reserves followed the order of leaf growth, root growth and tillering during the regrowth period. Although WSC reserves were identified as the primary contributor to plant regrowth following defoliation, there was also a strong relationship between stubble N concentration and regrowth variables.

A glasshouse study was undertaken to investigate the differences in rate of establishment, productivity, feed quality, and response to defoliation frequency between new and old cultivars within the brome (Bromus spp.) and cocksfoot (Dactylis glomerata L.) genera. Three of the more recent brome (Bareno, Gala, and Exceltas) and cocksfoot (Tekapo, Megatas, and Uplands) cultivars were compared with Matua and Kara, the most widely sown and utilised brome and cocksfoot dairy pasture cultivars, respectively. The improvements resulting from breeding and selection within the cocksfoot genera included faster seedling emergence and tiller production during establishment, higher tiller density once established, lower acid detergent fibre (ADF), higher crude protein (CP), and higher metabolisable energy (ME) concentrations. The newer cocksfoot cultivars had lower leaf and tiller dry matter (DM) yields than Kara, with little variation in ME levels between cultivars. The improvements resulting from breeding and selection within the brome genera, measured in this study, included faster seedling emergence, lower ADF, and higher CP concentrations. The higher fibre levels for Matua did not translate into a lower ME concentration; in fact, the energy content in Matua and Gala was higher than for all remaining cultivars. There were further similarities between Matua and Gala, the high water-soluble carbohydrate levels, leaf, and tiller DM yields of these cultivars, reflecting a strong regrowth response to defoliation. Further research in the field is required to confirm the observed variation within and between cocksfoot and brome cultivars, and to quantify the potential benefits of using the new v. the original cultivars.

A greenhouse study was undertaken to investigate the distribution of water-soluble carbohydrates (WSC) within the lower 100 mm of 'Kara' orchardgrass (Dactylis glomerata L.) and 'Matua' prairie grass (Bromus willdenowii Knnth.) stubble through four distinct regrowth cycles. Water-soluble carbohydrate levels were consistently higher in prairie grass tillers compared with orchardgrass tillers. A decrease in WSC levels with increasing stubble height was observed for vegetative tillers of both species. However, the WSC concentration gradient was better defined for orchardgrass, with a clear decrease in WSC concentration between the 21-to 30-and 31-to 40•mm segments, and 77% of WSC content contained within the O- to 30-mm stubble height range (with 0 mm representing the base at ground level). The WSC concentration gradient for prairie grass was less clearly defined, with a relatively high WSC concentration throughout the 0-to 100-mm stubble height range.

All organisms are subject to mutations as a result of normal cellular operations or interactions with the environment, leading to genetic variation (polymorphism). In conjunction with selection and genetic drift, there arises genetic variation within and among individuals and species. For this variation to be useful to geneticists, it must be heritable and discernable whether as a recognisable phenotypic variation or as a genetic mutation distinguishable through molecular techniques. PCR amplification and gel electrophoresis resolution of products using RAPD primer A2 shows polymorphism of up to 5 bands was evident. It also demonstrates that at the molecular level, there are banding differences that can be picked up between crossbred progeny sired by rams with high genetic merit for growth or muscle.Fat depth at the GR and C sites was significantly (P<0.05) influenced by level of nutrition and nutrition level x siretype interaction in that fat depths were greater in crossbred lambs fed at high levels of nutrition than those fed low nutrition levels. Lambs selected for growth and fed high level of nutrition produced carcasses with the least KNIFE GR fat depth of 11.4mm, a significant reduction from 18.1mm in the control group fed low level nutrition.

RAPD marker assays are based on polymerase chain reaction amplification of random segments of the DNA with an identical pair of primers 8-10 bp in length consisting of arbitrary nucleotide sequence. Genetic variation and divergence within and between breeds of interest are assessed by the presence or absence of each product which is dictated by the DNA sequence at each locus. The power to detect polymorphisms is very high given that 5-20 bands can be produced using a given primer pair and multiple sets of random primers can be used to scan the entire genome for differential RAPD bands. RAPD has several advantages over other molecular markers because it can be used with uncharacterised genomes without prior knowledge of nucleotide sequence information and can be applied to problems in which only small quantities of DNA are available. It is also efficient and inexpensive.At the same slaughter weight and body condition score, Corriedales had significantly (P<0.01) higher fat score, thicker subcutaneous fat (29.6 vs 23.3 mm) and wider eye muscle (49.8 vs 36.2 mm) than East Friesians. On the other hand, East Friesians had significantly (P<0.01) heavier hot carcass weight (23.8 vs 22.3 kg), larger eye muscle area (42.9 vs 39.5 cm2) and longer eye muscle (67.1 vs 65.6 mm) than Corriedales, while shortloin length (SLL) in the two breeds did not significantly differ (P>0.09).

All organisms are subject to mutations as a result of normal cellular operations or interactions with the environment, leading to genetic variation (polymorphism). In conjunction with selection and genetic drift, there arises genetic variation within and among individuals and species. For this variation to be useful to geneticists, it must be heritable and discernable whether as a recognisable phenotypic variation or as a genetic mutation distinguishable through molecular techniques. PCR amplification and gel electrophoresis resolution of products using RAPD primer A2 shows polymorphism of up to 5 bands was evident. It also demonstrates that at the molecular level, there are banding differences that can be picked up between crossbred progeny sired by rams with high genetic merit for growth or muscle.Fat depth at the GR and C sites was significantly (P<0.05) influenced by level of nutrition and nutrition level x siretype interaction in that fat depths were greater in crossbred lambs fed at high levels of nutrition than those fed low nutrition levels. Lambs selected for growth and fed high level of nutrition produced carcasses with the least KNIFE GR fat depth of 11.4mm, a significant reduction from 18.1mm in the control group fed low level nutrition.

In order to challenge old assumptions and break new grounds in teaching and learning in the Animal Sciences, a paradigm shift from the traditional ‘teacher-focus’ to a modern ‘student-centered’ learning approach is necessary. Establishing a synergy (systematic working together in concert) between ‘research-led’ teaching and ‘inquiry-based’ learning enhances students’ understanding of both science content and scientific practices (Edelson et al., 1999). Understanding the scientific concepts of genetics by nutrition interactions in Australian pasture-based sheep, dairy and beef systems is a major dilemma faced by undergraduate students. This difficulty was reflected in the 2006 Animal Production Systems (KLA220) Unit’s student evaluation of teaching and learning (SETL) at the University of Tasmania (UTAS). To address this problem, we implemented an innovative, inquiry-based learning and research-led teaching approach. The primary objective was to enhance students’ critical thinking and target their learning needs through active participation in field experimental trials and hands-on activities. Data from 104 students enrolled in the KLA220 Unit from 2006-2010 were utilized for this study. In addition to the theoretical concepts taught in class, students were exposed to hands-on genetics-nutrition experimental growth trials with sheep, laboratory experiments on intramuscular fat extraction, fat melting point, sensory evaluation of meat eating qualities, data analysis, livestock industry field visits, scientific journal article critiques and seminar presentations. Student learning experiences were evaluated through SETL surveys. On the basis of 83% response rate and quantitative Unit Evaluation mean scores, results indicated a progressive improvement from 3.90 in 2006 to 4.40 in 2010 that exceeded the average Faculty threshold. Free-text student comments revealed that the research-led teaching approach had actively engaged and given them a rich learning experience. This

Feeds and feeding account for a substantial cost of sheep production, hence the quest for alternative sources of nutrients that can facilitate fast growth in prime lambs without comprising meat eating quality is a continuous research endeavour. This study examined the effect of daily oral drenching of grazing prime lambs with a highly nutritious and edible blue-green microalga commonly referred to as Spirulina (Arthrospira platensis) as a supplement for nine weeks on meat eating quality and consumer acceptability. The prime lambs were weaners from Merino ewes sired by Dorset, White Suffolk, Black Suffolk and Merino rams randomly allocated to 3 levels of Spirulina supplementation treatment groups: Control (0%), low (10%wt/vol) and high (20%wt/vol) comprising 8 lambs per treatment. The lambs were balanced by gender (ewes and wethers), body condition score (average of 3.1±0.4) and body weight (average of 37.6±5.2 kg). Lambs were slaughtered in a commercial abattoir and Longissimus dorsi muscle samples barbequed. A consumer tasting panel subjectively evaluated the sensory meat eating qualities of tenderness, juiciness, aroma, appearance and overall liking. The data were subjected to statistical analyses utilising general linear model procedures in SAS with sire breed, sex, Spirulina level and their second-order interactions fitted as fixed effects and sire as a random variable. The consumer panel detected highly significant (p<0.001) differences in meat tenderness with the high supplementation group being the least tender (6.8±0.2) compared to the low (7.6±0.2) and control (8.0±0.2) groups out of a maximum possible score of 10. These results indicated that Spirulina supplementation at a 10% inclusion level produced leaner, healthier meats with relatively little impact on overall eating quality when compared to meat from animals at either 0% or 20% supplementation levels. This will enable prime lamb producers to make informed decisions regarding the most economically via

This study utilized leaf stage-based defoliation intervals to describe the concentrations and contents of watersoluble carbohydrate (WSC) and nitrogen (N) in stubble and root reserves and their effect on the regrowth of prairie grass (Bromus willdenowii Kunth.) plants. The priority sequence for allocation of WSC reserves during the regrowth period was also investigated. There were substantially higher concentrations of WSC and N in the stubble compared with the roots following defoliation, confirming the stubble as the primary site for energy storage, with roots playing a lesser role. However, high R2 values for the relationships between WSC concentration in roots and regrowth variables suggested that plants of prairie grass were reliant on WSC reserves from the roots in addition to the stubble to meet the energy requirements of plants until adequate photosynthetic tissue had been produced. The sequence of priority for allocation of WSC reserves followed the order of leaf growth, root growth and tillering during the regrowth period. Although WSC reserves were identified as the primary contributor to plant regrowth following defoliation, there was also a strong relationship between stubble N concentration and regrowth variables.

A glasshouse study was undertaken to investigate the differences in rate of establishment, productivity, feed quality, and response to defoliation frequency between new and old cultivars within the brome (Bromus spp.) and cocksfoot (Dactylis glomerata L.) genera. Three of the more recent brome (Bareno, Gala, and Exceltas) and cocksfoot (Tekapo, Megatas, and Uplands) cultivars were compared with Matua and Kara, the most widely sown and utilised brome and cocksfoot dairy pasture cultivars, respectively. The improvements resulting from breeding and selection within the cocksfoot genera included faster seedling emergence and tiller production during establishment, higher tiller density once established, lower acid detergent fibre (ADF), higher crude protein (CP), and higher metabolisable energy (ME) concentrations. The newer cocksfoot cultivars had lower leaf and tiller dry matter (DM) yields than Kara, with little variation in ME levels between cultivars. The improvements resulting from breeding and selection within the brome genera, measured in this study, included faster seedling emergence, lower ADF, and higher CP concentrations. The higher fibre levels for Matua did not translate into a lower ME concentration; in fact, the energy content in Matua and Gala was higher than for all remaining cultivars. There were further similarities between Matua and Gala, the high water-soluble carbohydrate levels, leaf, and tiller DM yields of these cultivars, reflecting a strong regrowth response to defoliation. Further research in the field is required to confirm the observed variation within and between cocksfoot and brome cultivars, and to quantify the potential benefits of using the new v. the original cultivars.

A greenhouse study was undertaken to investigate the distribution of water-soluble carbohydrates (WSC) within the lower 100 mm of 'Kara' orchardgrass (Dactylis glomerata L.) and 'Matua' prairie grass (Bromus willdenowii Knnth.) stubble through four distinct regrowth cycles. Water-soluble carbohydrate levels were consistently higher in prairie grass tillers compared with orchardgrass tillers. A decrease in WSC levels with increasing stubble height was observed for vegetative tillers of both species. However, the WSC concentration gradient was better defined for orchardgrass, with a clear decrease in WSC concentration between the 21-to 30-and 31-to 40•mm segments, and 77% of WSC content contained within the O- to 30-mm stubble height range (with 0 mm representing the base at ground level). The WSC concentration gradient for prairie grass was less clearly defined, with a relatively high WSC concentration throughout the 0-to 100-mm stubble height range.

All organisms are subject to mutations as a result of normal cellular operations or interactions with the environment, leading to genetic variation (polymorphism). In conjunction with selection and genetic drift, there arises genetic variation within and among individuals and species. For this variation to be useful to geneticists, it must be heritable and discernable whether as a recognisable phenotypic variation or as a genetic mutation distinguishable through molecular techniques. PCR amplification and gel electrophoresis resolution of products using RAPD primer A2 shows polymorphism of up to 5 bands was evident. It also demonstrates that at the molecular level, there are banding differences that can be picked up between crossbred progeny sired by rams with high genetic merit for growth or muscle.Fat depth at the GR and C sites was significantly (P<0.05) influenced by level of nutrition and nutrition level x siretype interaction in that fat depths were greater in crossbred lambs fed at high levels of nutrition than those fed low nutrition levels. Lambs selected for growth and fed high level of nutrition produced carcasses with the least KNIFE GR fat depth of 11.4mm, a significant reduction from 18.1mm in the control group fed low level nutrition.

RAPD marker assays are based on polymerase chain reaction amplification of random segments of the DNA with an identical pair of primers 8-10 bp in length consisting of arbitrary nucleotide sequence. Genetic variation and divergence within and between breeds of interest are assessed by the presence or absence of each product which is dictated by the DNA sequence at each locus. The power to detect polymorphisms is very high given that 5-20 bands can be produced using a given primer pair and multiple sets of random primers can be used to scan the entire genome for differential RAPD bands. RAPD has several advantages over other molecular markers because it can be used with uncharacterised genomes without prior knowledge of nucleotide sequence information and can be applied to problems in which only small quantities of DNA are available. It is also efficient and inexpensive.At the same slaughter weight and body condition score, Corriedales had significantly (P<0.01) higher fat score, thicker subcutaneous fat (29.6 vs 23.3 mm) and wider eye muscle (49.8 vs 36.2 mm) than East Friesians. On the other hand, East Friesians had significantly (P<0.01) heavier hot carcass weight (23.8 vs 22.3 kg), larger eye muscle area (42.9 vs 39.5 cm2) and longer eye muscle (67.1 vs 65.6 mm) than Corriedales, while shortloin length (SLL) in the two breeds did not significantly differ (P>0.09).

All organisms are subject to mutations as a result of normal cellular operations or interactions with the environment, leading to genetic variation (polymorphism). In conjunction with selection and genetic drift, there arises genetic variation within and among individuals and species. For this variation to be useful to geneticists, it must be heritable and discernable whether as a recognisable phenotypic variation or as a genetic mutation distinguishable through molecular techniques. PCR amplification and gel electrophoresis resolution of products using RAPD primer A2 shows polymorphism of up to 5 bands was evident. It also demonstrates that at the molecular level, there are banding differences that can be picked up between crossbred progeny sired by rams with high genetic merit for growth or muscle.Fat depth at the GR and C sites was significantly (P<0.05) influenced by level of nutrition and nutrition level x siretype interaction in that fat depths were greater in crossbred lambs fed at high levels of nutrition than those fed low nutrition levels. Lambs selected for growth and fed high level of nutrition produced carcasses with the least KNIFE GR fat depth of 11.4mm, a significant reduction from 18.1mm in the control group fed low level nutrition.

RAPD marker assays are based on polymerase chain reaction amplification of random segments of the DNA with an identical pair of primers 8-10 bp in length consisting of arbitrary nucleotide sequence. Genetic variation and divergence within and between breeds of interest are assessed by the presence or absence of each product which is dictated by the DNA sequence at each locus. The power to detect polymorphisms is very high given that 5-20 bands can be produced using a given primer pair and multiple sets of random primers can be used to scan the entire genome for differential RAPD bands. RAPD has several advantages over other molecular markers because it can be used with uncharacterised genomes without prior knowledge of nucleotide sequence information and can be applied to problems in which only small quantities of DNA are available. It is also efficient and inexpensive.At the same slaughter weight and body condition score, Corriedales had significantly (P<0.01) higher fat score, thicker subcutaneous fat (29.6 vs 23.3 mm) and wider eye muscle (49.8 vs 36.2 mm) than East Friesians. On the other hand, East Friesians had significantly (P<0.01) heavier hot carcass weight (23.8 vs 22.3 kg), larger eye muscle area (42.9 vs 39.5 cm2) and longer eye muscle (67.1 vs 65.6 mm) than Corriedales, while shortloin length (SLL) in the two breeds did not significantly differ (P>0.09).

RAPD marker assays are based on polymerase chain reaction amplification of random segments of the DNA with an identical pair of primers 8-10 bp in length consisting of arbitrary nucleotide sequence. Genetic variation and divergence within and between breeds of interest are assessed by the presence or absence of each product which is dictated by the DNA sequence at each locus. The power to detect polymorphisms is very high given that 5-20 bands can be produced using a given primer pair and multiple sets of random primers can be used to scan the entire genome for differential RAPD bands. RAPD has several advantages over other molecular markers because it can be used with uncharacterised genomes without prior knowledge of nucleotide sequence information and can be applied to problems in which only small quantities of DNA are available. It is also efficient and inexpensive.At the same slaughter weight and body condition score, Corriedales had significantly (P<0.01) higher fat score, thicker subcutaneous fat (29.6 vs 23.3 mm) and wider eye muscle (49.8 vs 36.2 mm) than East Friesians. On the other hand, East Friesians had significantly (P<0.01) heavier hot carcass weight (23.8 vs 22.3 kg), larger eye muscle area (42.9 vs 39.5 cm2) and longer eye muscle (67.1 vs 65.6 mm) than Corriedales, while shortloin length (SLL) in the two breeds did not significantly differ (P>0.09).