The value of genetic fatness in Merino ewes differs with production system and environment

2010 ◽  
Vol 50 (12) ◽  
pp. 1011 ◽  
Author(s):  
M. B. Ferguson ◽  
J. M. Young ◽  
G. A. Kearney ◽  
G. E. Gardner ◽  
I. R. D. Robertson ◽  
...  
Keyword(s):  
Production System ◽  
Selection Pressure ◽  
Production Systems ◽  
High Response ◽  
Economic Modelling ◽  
Sheep Industry ◽  
True Value ◽  
Australian Sheep ◽  
Sheep Production ◽  
Small Change

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.

Improving sheep production and welfare in extensive systems through precision sheep management

2012 ◽  
Vol 52 (7) ◽  
pp. 665 ◽  
Author(s):  
Jessica E. Morris ◽  
Greg M. Cronin ◽  
Russell D. Bush
Keyword(s):  
Radio Frequency ◽  
Radio Frequency Identification ◽  
Production Efficiency ◽  
Sheep Industry ◽  
Monitoring Frequency ◽  
Frequency Identification ◽  
Australian Sheep ◽  
Sheep Production ◽  
The Cost ◽  
Improve Production Efficiency

This overview discusses how precision sheep management could be utilised in the Australian sheep industry to improve production efficiency and reduce animal welfare concerns due to low monitoring frequency by stockpeople. The concept of precision sheep management is described. This is a system in which sheep are managed as individuals or small groups rather than as a (whole) flock. Precision sheep management utilises the application of radio frequency identification technology, enabling producers to better monitor sheep in extensive situations, and contribute to improved efficiency of management and sheep welfare. Examples of combining radio frequency identification with other technologies such as walk-over-weighing and Pedigree Matchmaker are discussed. These technologies provide producers with tools to improve the cost effectiveness of, and labour efficiency associated with, collecting data on individual animals. The combined technologies should also improve consistency and reliability of information, enhancing decision-making by producers, for example, from regular monitoring of biometric variables such as liveweight, or calculating breeding values to enable superior genetic comparisons over time.

A bio-economic approach to estimating economic values for UK hill sheep

2000 ◽  
Vol 2000 ◽  
pp. 39-39 ◽  
Author(s):  
J. Conington ◽  
S. Bishop ◽  
A. Waterhouse ◽  
G. Simm
Keyword(s):  
Production Systems ◽  
Farm Size ◽  
Economic Values ◽  
Physical Constraints ◽  
Sheep Industry ◽  
Breeding Goal ◽  
Selection Indexes ◽  
Sheep Production ◽  
Combine Information ◽  
Economic Selection

Profitability of sheep production systems depends on several different animal characteristics rather than a single trait. Economic selection indexes combine information from more than one trait into an overall score, to maximise genetic gain. Economic values (EVs) are required for each trait in the breeding goal so that selection emphasis is proportional to the economic importance of each trait. Defining clear breeding goals is more complex for hill breeds than for other sectors of the sheep industry because they provide breeding females in addition to lambs for slaughter. The aims of this paper are to i) describe how EVs for breeding goal traits suitable for UK hill sheep were derived for a combination of carcass, maternal and ‘sustainability’ traits using a bio-economic model, and ii) show how these EVs vary between different production systems as a result of the differences in the physical constraints of farm size, pasture availability and the biological limits of sheep in extensive rearing environments.

Season and reproductive status rather than genetics factors influence change in ewe weight and fat over time. 3. Analysis of Merino ewes

2014 ◽  
Vol 54 (6) ◽  
pp. 821 ◽  
Author(s):  
S. F. Walkom ◽  
F. D. Brien ◽  
M. L. Hebart ◽  
S. I. Mortimer ◽  
W. S. Pitchford
Keyword(s):  
Genetic Variation ◽  
Body Condition ◽  
Production Systems ◽  
Genetic Effect ◽  
Additive Genetic Effect ◽  
Production Cycle ◽  
Production Cycles ◽  
Australian Sheep ◽  
Sheep Production ◽  
Stocking Rates

The profitability of southern Australian sheep production systems depends on the optimisation of stocking rates by meeting the nutritional demands of the breeding ewe while effectively utilising grown pasture. The aim of the study was to evaluate the genetic variation in liveweight and body condition of Merino ewes across their breeding life within a wool-based enterprise. The results were consistent with findings in crossbred ewes and showed that the genetic component of weight and body condition remained constant across the production cycle and age. The overall additive genetic effect accounted for 92% of the genetic variation in weight of Merino ewes bred across five production cycles. A genetic correlation of 0.85 suggested that ewes that were superior at maintaining their condition when rearing a single lamb would maintain this superiority when rearing multiple lambs. To improve weight and condition of Merino ewes during the ‘tough’ times, when nutrient requirements are not met by the pasture, selection can be made at any time and this will result in increased genetic condition at all times.

scholarly journals First Report of Anthelmintic Resistance in Gastrointestinal Nematodes of Sheep from Costa Rica

2011 ◽  
Vol 2011 ◽  
pp. 1-4 ◽  
Author(s):  
R. Maroto ◽  
A. E. Jiménez ◽  
J. J. Romero ◽  
V. Alvarez ◽  
J. B. De Oliveira ◽  
...  
Keyword(s):  
Costa Rica ◽  
Chemical Control ◽  
Production Systems ◽  
Anthelmintic Resistance ◽  
Gastrointestinal Nematodes ◽  
Visual Estimation ◽  
Treatment Groups ◽  
Sheep Industry ◽  
Fecal Egg Count ◽  
Sheep Production

As the prevalence and severity of anthelmintic resistance continue to rise, nematode infections in sheep correspondingly reduce the profitability of the sheep industry. In Costa Rica, sheep production systems are increasing in both number and importance. A field trial study was carried out to detect the level of anthelmintic resistance to albendazole and ivermectin in gastrointestinal nematodes (GIN) of sheep from seven farms in Costa Rica. Resistance was determined using the fecal egg count reduction test (FECRT). Three treatment groups were assessed on each farm: control, albendazole, and ivermectin.Haemonchusspp. (71%),Strongyloidessp. (57%), andTrichostrongylusspp. (43%) presented resistance levels to albendazole, whereasStrongyloidessp. (43%),Haemonchusspp. (29%), andTrichostrongylusspp. (29%) were resistant to ivermectin.Haemonchusspp.,Strongyloidessp., andTrichostrongylusspp. were the most resistant GIN to both products. This study suggests that frequency of treatment, exclusive chemical control, and visual estimation of animal weight to calculate dosage may contribute to the high levels of anthelmintic resistance that were observed on the farms analyzed herein.

scholarly journals Soil Bacterial Community Diversity and Composition as Affected by Tillage Intensity Treatments in Corn-Soybean Production Systems

2021 ◽  
Vol 12 (1) ◽  
pp. 157-172
Author(s):  
Shankar G. Shanmugam ◽  
Normie W. Buehring ◽  
Jon D. Prevost ◽  
William L. Kingery
Keyword(s):  
Microbial Community ◽  
Bacterial Community ◽  
Community Composition ◽  
Production System ◽  
Soil Microbial Community ◽  
Production Systems ◽  
Bacterial Community Composition ◽  
Soybean Production ◽  
Soil Microbial ◽  
Soil Bacterial

Our understanding on the effects of tillage intensity on the soil microbial community structure and composition in crop production systems are limited. This study evaluated the soil microbial community composition and diversity under different tillage management systems in an effort to identify management practices that effectively support sustainable agriculture. We report results from a three-year study to determine the effects on changes in soil microbial diversity and composition from four tillage intensity treatments and two residue management treatments in a corn-soybean production system using Illumina high-throughput sequencing of 16S rRNA genes. Soil samples were collected from tillage treatments at locations in the Southern Coastal Plain (Verona, Mississippi, USA) and Southern Mississippi River Alluvium (Stoneville, Mississippi, USA) for soil analysis and bacterial community characterization. Our results indicated that different tillage intensity treatments differentially changed the relative abundances of bacterial phyla. The Mantel test of correlations indicated that differences among bacterial community composition were significantly influenced by tillage regime (rM = 0.39, p ≤ 0.0001). Simpson’s reciprocal diversity index indicated greater bacterial diversity with reduction in tillage intensity for each year and study location. For both study sites, differences in tillage intensity had significant influence on the abundance of Proteobacteria. The shift in the soil bacterial community composition under different tillage systems was strongly correlated to changes in labile carbon pool in the system and how it affected the microbial metabolism. This study indicates that soil management through tillage intensity regime had a profound influence on diversity and composition of soil bacterial communities in a corn-soybean production system.

A New Procedure of Production Orders Sequencing in Mixed-Model Production Systems

2014 ◽  
Vol 1036 ◽  
pp. 864-868 ◽  
Author(s):  
Marcin Zemczak ◽  
Damian Krenczyk
Keyword(s):  
Task Scheduling ◽  
Production System ◽  
Mixed Model ◽  
Production Systems ◽  
Production Capacity ◽  
Approximate Solutions ◽  
Task Sequence ◽  
Optimal Method ◽  
Sequencing Problem ◽  
Car Sequencing

The paper presents the task scheduling issue, which main aim is to establish a proper sequence of tasks, that would maximize the utilization of companys production capacity. According to the literature sources, the presented sequencing problem, denoted as CSP (Car Sequencing Problem) belongs to the NP-hard class, as has been proven by simple reduction from Hamiltonians Path problem. Optimal method of solution has not yet been found, only approximate solutions have been offered, especially from the range of evolutionary algorithms. Regardless of specific production system, while considering reception of new tasks into the system, current review of the state of the system is required in order to decide whether and when a new order can be accepted for execution. In this paper, the problem of task scheduling is limited to the specific existing mixed-model production system. The main goal is to determine the effective method of creation of task sequence. Through the use of computational algorithms, and automatic analysis of the resulting sequence, rates of production are able to be checked in a real time, and so improvements can be proposed and implemented.

scholarly journals Using Computer Simulation Method to Improve Throughput of Production Systems by Buffers and Workers Allocation

2015 ◽  
Vol 6 (4) ◽  
pp. 60-69 ◽  
Author(s):  
Sławomir Kłos ◽  
Peter Trebuna
Keyword(s):  
Computer Simulation ◽  
Production System ◽  
Production Systems ◽  
Simulation Method ◽  
System Throughput ◽  
Buffer Allocation ◽  
Simulation Experiments ◽  
Buffer Capacities ◽  
The Relationship ◽  
Support Decision Making

Abstract This paper proposes the application of computer simulation methods to support decision making regarding intermediate buffer allocations in a series-parallel production line. The simulation model of the production system is based on a real example of a manufacturing company working in the automotive industry. Simulation experiments were conducted for different allocations of buffer capacities and different numbers of employees. The production system consists of three technological operations with intermediate buffers between each operation. The technological operations are carried out using machines and every machine can be operated by one worker. Multi-work in the production system is available (one operator operates several machines). On the basis of the simulation experiments, the relationship between system throughput, buffer allocation and the number of employees is analyzed. Increasing the buffer capacity results in an increase in the average product lifespan. Therefore, in the article a new index is proposed that includes the throughput of the manufacturing system and product life span. Simulation experiments were performed for different configurations of technological operations.

Evaluation of a new technology when applied to sheep production systems: Part I—Model description

1989 ◽  
Vol 29 (1) ◽  
pp. 35-47 ◽  
Author(s):  
P.J. Bowman ◽  
D.A. Wysel ◽  
D.G. Fowler ◽  
D.H. White
Keyword(s):  
Production Systems ◽  
New Technology ◽  
Model Description ◽  
Sheep Production

Responsive Production Systems and Roles that Robots can Play

2009 ◽  
Vol 62-64 ◽  
pp. 275-292
Author(s):  
R.H. Weston
Keyword(s):  
Building Block ◽  
Production System ◽  
World Wide ◽  
Production Systems ◽  
Industrial Robots ◽  
Robotic Systems ◽  
Different Types ◽  
Useful Lifetime

With increased product dynamics world-wide, the average economic lifetime of production systems is falling. Industrial robots are widely assumed to be inherently flexible and therefore that they can function as a programmable building block of response production systems. This paper reviews common capabilities of contemporary industrial robotic systems and investigates their capability to extend the useful lifetime of production system by coping with different types of product dynamic. Also considered are relative capabilities of conventional programmable robots and an emerging generation of programmable and configurable component-based machines.

System dynamics modelling of fixed and dynamic Kanban controlled production systems: a supply chain perspective

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Jagan Mohan Reddy K. ◽  
Neelakanteswara Rao A. ◽  
Krishnanand Lanka ◽  
PRC Gopal
Keyword(s):  
Supply Chain ◽  
System Dynamics ◽  
Cycle Time ◽  
Production System ◽  
Demand Uncertainty ◽  
Production Systems ◽  
Decision Variable ◽  
Content Type ◽  
Pull Production ◽  
Kanban System

Purpose Pull production systems have received much attention in the supply chain management environment. The number of Kanbans is a key decision variable in the pull production system as it affects the finished goods inventory (FGI) and backorders of the system. The purpose of this study is to compare the performance of the fixed and dynamic Kanban systems in terms of operational metrics (FGI and backorders) under the demand uncertainty. Design/methodology/approach In this paper, the system dynamics (SD) approach was used to model the performance of fixed and dynamic Kanban based production systems. SD approach has enabled the feedback mechanism and is an appropriate tool to incorporate the dynamic control during the simulation. Initially, a simple Kanban based production system was developed and then compared the performance of production systems with fixed and dynamic controlled Kanbans at the various demand scenarios. Findings From the present study, it is observed that the dynamic Kanban system has advantages over the fixed Kanban system and also observed that the variation in the backorders with respect to the demand uncertainty under the dynamic Kanban system is negligible. Research limitations/implications In a just-in-time production system, the number of Kanbans is a key decision variable. The number of Kanbans is mainly depended on the demand, cycle time, safety stock factor (SSF) and container size. However, this study considered only demand uncertainty to compare the fixed and dynamic Kanban systems. This paper further recommends researchers to consider other control variables which may influence the number of Kanbans such as cycle time, SSF and container size. Originality/value This study will be useful to decision-makers and production managers in the selection of the Kanban systems in uncertain demand applications.

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