Selection schemes for improving both reproduction rate and clean wool weight in the Australian Merino under field conditions

1965 ◽  
Vol 16 (5) ◽  
pp. 863 ◽  
Author(s):  
SY Young ◽  
Turner H Newton

Theoretical consideration has been given to 28 selection schemes which might readily be applied for the improvement of both number of lambs born and clean wool weight per head in Australian Merino sheep under field conditions. Two sets of relative weights were used, one lamb being considered equivalent to 5 or 10 lb of clean wool, and when both characters were selected in one sex, equal selection pressure was applied to each. Quality of wool is assumed to be safeguarded by preliminary culling of off-types. The schemes were investigated at two levels of twinning (15 and 30%). At both levels, the optimal method of ram selection was to select on clean wool weight among twin-born rams. At the lower level, the optimal method of ewe selection was to save twin-born ewes and to make up numbers by selecting on clean wool weight among those born as singles. At the higher level, this scheme was slightly exceeded in total genetic gain by one involving selection of ewes on their own 3-year-old reproduction rate. After 10 years of selection under the optimal scheme, an increase of about 40 lambs born per 100 ewes joined would be expected in reproduction rate, and about 1.2 lb clean wool in the cut per head. The gain in wool weight will be less (about 1 lb) if more rigorous culling on crimp is practiced, but the relative efficiency of the schemes near the optimum will not be changed. The tables presented could be used in flocks of any breed in which clean wool weight and reproduction rate were uncorrelated and to which approximately the same estimates of heritability, variances, and relative weights of lamb and wool could be applied.

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 1941 ◽  
Author(s):  
Bartosz Szeląg ◽  
Jakub Drewnowski ◽  
Grzegorz Łagód ◽  
Dariusz Majerek ◽  
Ewa Dacewicz ◽  
...  

The paper presented the methodology for the construction of a soft sensor used for activated sludge bulking identification. Devising such solutions fits within the current trends and development of a smart system and infrastructure within smart cities. In order to optimize the selection of the data-mining method depending on the data collected within a wastewater treatment plant (WWTP), a number of methods were considered, including: artificial neural networks, support vector machines, random forests, boosted trees, and logistic regression. The analysis conducted sought the combinations of independent variables for which the devised soft sensor is characterized with high accuracy and at a relatively low cost of determination. With the measurement results pertaining to the quantity and quality of wastewater as well as the temperature in the activated sludge chambers, a good fit can be achieved with the boosted trees method. In order to simplify the selection of an optimal method for the identification of activated sludge bulking depending on the model requirements and the data collected within the WWTP, an original system of weight estimation was proposed, enabling a reduction in the number of independent variables in a model—quantity and quality of wastewater, operational parameters, and the cost of conducting measurements.


1968 ◽  
Vol 19 (3) ◽  
pp. 443 ◽  
Author(s):  
HN Turner ◽  
GH Brown ◽  
GH Ford

In a flock of breeding ewes of fixed size, the number of age groups of rams and ewes influences the annual rate of genetic gain in any character under selection. The number of ewe age groups also influences the number of surplus stock aged 1½ years, and the number cast for age, as well as the amount and quality of wool obtained. The latter is also influenced by the proportion of ewes which rear no lambs, one, or two, as well as the proportion themselves born in multiple births or as the progeny of young ewes. In this paper, all these influences are considered in determining the age structure of the breeding flock which gives the greatest number of surplus stock and the greatest relative wool return. To combine the two, relative weights have to be given to wool and surplus stock. One such set of weights has been used, and the conclusion has been drawn that two age groups of rams, with either five or six age groups of ewes, give optimal return, the number of ewe groups depending on the level of reproduction rate. This conclusion depends on the relative weights used. In cases where numbers of animals are of supreme importance, such as after a drought or at a time of increasing pasture improvement, then retaining ewes to an older age would increase the number of surplus young stock.


1960 ◽  
Vol 11 (4) ◽  
pp. 604 ◽  
Author(s):  
SSY Young ◽  
Turner H Newton ◽  
CHS Dolling

Heritability estimates were calculated for 10 traits in rams and ewes of a medium-woolled strain of Australian Merino sheep. The traits were greasy wool weight, clean scoured yield, clean wool weight, body weight, wrinkle score, face cover score, fibre population density, fibre diameter, staple length, and crimps per inch. Estimates were made by dam-offspring correlations, measurement on the dams being at 15-16 months, on daughters at 15-16 months, and on sons at both 10-12 and 15-16 months. All estimates for both sexes lay between 0.3 and 0.6, except for fibre population density (0.24) and fibre diameter (0.12) in rams at 15-16 months and for clean wool weight (0.29) and face cover score (0.29) in rams at 10-12 months. The only significant sex difference lay in the lower figure for fibre diameter in rams at 15-16 months, but this is of doubtful importance as the corresponding figure for rams at 10-12 months (0.37) did not differ significantly from the ewe figure. All traits may be considered highly heritable, and the high values for the yearling rams indicate that consideration might be given to the selection of rams for production traits at an earlier age than the traditional one of 18 months or older.


1978 ◽  
Vol 18 (94) ◽  
pp. 635 ◽  
Author(s):  
TLJ Mann ◽  
DE Taplin ◽  
RE Brady

Divergent selection for fecundity in a South Australian Merino flock was carried out over a 10 year period at Roseworthy Agricultural College, South Australia. Comparisons were made between two flocks of sheep in which selection was restricted to ram replacements. Analyses showed that very little response was achieved. Pooled estimates of repeatability by analysis of variance were 0.04 for lambs born per ewe joined (LBJ) and 0.14 for lambs born per ewe lambing (LBP). Pooled half-sib estimates of heritability were 0,10 for LBJ and 0.10 for LBP. The realized heritability of LBP was 0.03, averaged over age groups. The lack of response was due to limited selection pressure and the time taken for improvement to pass through the breeding flock.


1990 ◽  
Vol 41 (4) ◽  
pp. 769 ◽  
Author(s):  
DJ Cottle

The impact of fluctuating wool prices on setting economic values (EVs) in selection indices, e.g. WOOLPLAN, are studied by modelling genetic change in a flock following index selection, Operating under different wool price regimes. Because future price changes are difficult to predict, there is no guaranteed, optimal method of determining EVs. One possibility is the use of a moving regression of the last five years' wool prices (in real terms), rather than setting the index once, or every five years, or every year, based on current prices. The ratio (R) of clean wool price to micron premium is more important than actual prices. It is suggested that the default EVs used currently in WOOLPLAN are appropriate for strong wool Merino flocks. The choice and implications of EVs in other situations are discussed.


1952 ◽  
Vol 3 (4) ◽  
pp. 409 ◽  
Author(s):  
FHW Morley

Theoretical consequences of the use of progeny testing, sib testing, and mass selection are examined in a flock of 1,000 ewes producing 700 progeny of breeding age each year. Selection based on a combination of individual merit and merit of half-sibs should result in approximately the same annual improvement as that achieved by optimum use of progeny-tested sires. In large flocks extensive use of outstanding sires by artificial insemination may increase progress for traits with heritability of about 0.3 by a factor of about 1.2 as compared with mass selection. The advantages to be gained by progeny testing and artificial insemination may be outweighed by the dangers of inbreeding, and the cost involved would have to be considered. As most of these advantages should be achieved by combination or even by mass selection, which avoid inbreeding and much of the cost, progeny testing with wide use of progeny-tested sires is unlikely to be the most economical road to flock improvement.


2016 ◽  
Vol 15 ◽  
pp. 163-171
Author(s):  
M. G. Shcherbakovskiy

The article discusses the reasonsfor an expert to participate in legal proceedings. The gnoseological reason for that consists of the bad quality of materials subject to examination that renders the examination either completely impossible or compromises objective, reasoned and reliable assessment of the findings. The procedural reason consists ofa proscription for an expert to collect evidence himself or herself. The author investigates into the ways of how an expert can participate in legal proceedings. If the defense invites an expert to participate in the proceedings, then it is recommended that his or her involvement should be in the presence of attesting witnesses and recorded in the protocol. In the course of the legal proceedings an expert has the following tasks: adding initial data, acquiring new initial data, understanding the situation of the incident, acquiring new objects to be studied, including samples for examination. An expert’s participation in legal proceedings differs from the participation of a specialist or an examination on the scene of the incident. The author describes the tasks that an expert solves in the course of legal proceedings, the peculiarities ofan investigation experiment practices, the selection of samples for an examination, inspection, interrogation.


2019 ◽  
Vol 9 (01) ◽  
pp. 47-54
Author(s):  
Rabbai San Arif ◽  
Yuli Fitrisia ◽  
Agus Urip Ari Wibowo

Voice over Internet Protocol (VoIP) is a telecommunications technology that is able to pass the communication service in Internet Protocol networks so as to allow communicating between users in an IP network. However VoIP technology still has weakness in the Quality of Service (QoS). VOPI weaknesses is affected by the selection of the physical servers used. In this research, VoIP is configured on Linux operating system with Asterisk as VoIP application server and integrated on a Raspberry Pi by using wired and wireless network as the transmission medium. Because of depletion of IPv4 capacity that can be used on the network, it needs to be applied to VoIP system using the IPv6 network protocol with supports devices. The test results by using a wired transmission medium that has obtained are the average delay is 117.851 ms, jitter is 5.796 ms, packet loss is 0.38%, throughput is 962.861 kbps, 8.33% of CPU usage and 59.33% of memory usage. The analysis shows that the wired transmission media is better than the wireless transmission media and wireless-wired.


Author(s):  
Fahmi Yunistyawan ◽  
Yunistyawan J Berchmans ◽  
Gembong Baskoro

This study implements the auto start control system on an electric motor 3 phase C4Feeding pump when the discharge pressure is low-low (4.3 kg /cm²). The C4 feeding pumpmotor was initially manually operated from the local control station, this was very ineffectiveand inefficient because it still relied on the field operator to operate the pump motor and whenthe plant was in normal operating it is very risk if the field operator late to operate motor then itwill impact to quality of the product, and if the delay time to operate motor is too long then planthave to shut down, therefore improvement is needed in the C4 feeding pump motor controlsystem. In this paper, various types of 3-phase motor control are explained which allow it to beapplied to the C4 feeding pump motor that are on-off, inverter, and variable speed drive andefficient selection of the three systems control of the motor. Software and hardware used in thisthesis work are DCS CENTUM VP Yokogawa.


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