DEVELOPMENT OF THE ROMNELET SHEEP

1961 ◽  
Vol 41 (1) ◽  
pp. 102-108 ◽  
Author(s):  
H. F. Peters ◽  
S. B. Slen ◽  
H. J. Hargrave

In 1935 the Canada Department of Agriculture undertook the development of a new breed of sheep at the Experimental Farm, Manyberries, Alberta. The foundation stock consisted of 15 Romney Marsh rams and 520 Rambouillet ewes, with introductions of 1 Targhee ram in 1942 and 6 Romeldale rams in 1944. Two of the Romeldale rams were used again in 1945. The flock has been closed to outside introductions since 1945 and the breed which resulted has been named "Romnelet".Following the first cross, the F1 animals were inter-mated and no back-crosses were made. A genealogical study up to, and including, 1955 showed the average annual size of the breeding flock to be 10 rams and 338 ewes and the average generation interval 3.5 years. On the average, there were 13 rams and 301 ewes selected per generation. The mean inbreeding coefficient of the 1955 lambs was 8 per cent.Romnelets are polled, open-faced, free from skin wrinkles, with white face and legs and a fleece of [Formula: see text] or [Formula: see text] staple wool. Means and standard deviations of performance traits in the new breed under range conditions are reported.

1969 ◽  
Vol 49 (3) ◽  
pp. 237-246 ◽  
Author(s):  
H. T. Fredeen ◽  
J. G. Stothart

The Lacombe breed of pigs, released to the public in 1958, culminated a 12-year developmental research program conducted at the Canada Department of Agriculture Research Station, Lacombe, Alberta. This report describes and summarizes details of the foundation stock, mating plan and selection program used.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Louis M. Houston

We derive a general equation for the probability that a measurement falls within a range of n standard deviations from an estimate of the mean. So, we provide a format that is compatible with a confidence interval centered about the mean that is naturally independent of the sample size. The equation is derived by interpolating theoretical results for extreme sample sizes. The intermediate value of the equation is confirmed with a computational test.


PEDIATRICS ◽  
1965 ◽  
Vol 36 (1) ◽  
pp. 62-66
Author(s):  
Edward J. O'Connell ◽  
Robert H. Feldt ◽  
Gunnar B. Stickler

The purpose of this study was to re-affirm our clinical impression that non-institutionalized children whose head circumference was below minus 2 standard deviations were mentally subnormal and frequently had growth failure. A group of 134 children with a head circumference below minus 2 standard deviations from the mean were studied, and all but one were mentally subnormal. The most severe mental retardation was noted in the group of children with a head circumference of minus 4 standard deviations or below. We found, as have others, that children with mental retardation have height and weights below the expected norm and that children with a head circumference below minus 2 standard deviations have even lower mean heights and weights. The head circumference of 31 children with growth failure and normal intelligence was normal for age and sex, therefore disproving the concept that the abnormally small child has a proportionally small head. In the child with growth failure, should the head be proportionally small (below minus 2 standard deviations), mental subnormality should be suspected. We feel that the head circumference measurement has taken on new clinical significance in that our data support its use in suspecting the association of mental subnormality in children with growth failure and a head circumference of below minus 2 standard deviations from the mean for age and sex.


Author(s):  
Barbara J. Kelso

A legibility study was performed to investigate the effects of scale factors, graduation marks, orientation of scales, and reading conditions on the speed and accuracy of reading moving-tape instruments. Each of 150 Air Force Officers made 150 self-paced readings from slides of hand drawn tape instruments. Error was expressed as the magnitude of deviation of a subjects' verbal response from the set scale value. An analysis of variance was performed on the mean error scores, standard deviations of error, mean reaction times, and standard deviations of reaction times. The results clearly favored the 1 7/8 inch scale factor over the 1 3/8 inch and the 2 3/8 scale factor. The use of 9 graduation marks was superior to either 0, 1, 3, or 4 graduation marks. Reading conditions had little effect on performance. Horizontal scales were read more rapidly but no more accurately than vertical scales.


1974 ◽  
Vol 18 (2) ◽  
pp. 116-116
Author(s):  
Helmut T. Zwahlen

Twelve subjects (20–37 years old) were tested in the laboratory and eleven out of these were also tested in a car in the field, first under a no alcohol condition and then under an alcohol condition (approximately 0.10% BAC). In the laboratory the subjects simple and choice reaction times for two uncertainty modes were measured and their information processing rates (3 bits unsertainty) were determined. In the field the subjects driving skill for driving through a gap with 20 inches total clearance at 20 MPH was measured, as well as their static visual perceptual capabilities and risk acceptance decisions for a 46 feet viewing distance using psychophysical experimental methods. Based upon the driving skill measure (standard deviation of centerline deviations in the gap), the mean of the psychometric visual gap perception function and the mean of the psychometric gap risk acceptance function, the “Safety Distance” and the “Driver Safety Index” (DSI) were obtained. Based upon a statistical analysis of the data we may conclude first that the effects of alcohol (approximately 0.10% BAC) vary widely from one subject to another (slighthly improved performance to highly impaired performance) and that the changes in the group averages of the means and standard deviations of the psychometric visual perception and risk acceptance functions, the driving skill distributions, the “Safety Distances” and the DSI's for the subjects (although all changes in the group averages are in the expected direction) are statistically not significant (α = .05). Second, the group average of the means of the choice reaction times for the subjects increased by 5% under the alcohol condition (statistically significant, α = .05), but more important the group average of the standard deviations of the choice reaction times for the subjects increased by 23% (statistically significant, α = .05). The group average of the information processing rates for the subjects decreased by 3% (statistically not significant, α = .05) under the alcohol condition. A system model in which the system demands on the driver are represented in terms of choice reaction times is used to demonstrate that the increase in performance variability (expressed by the standard deviation of choice reaction times) under the influence of alcohol provides a much better explanation for the higher accident involvement than the historically most frequently used rather small increase in average performance (expressed by the mean of choice reaction times).


2004 ◽  
Vol 47 (2) ◽  
pp. 141-153 ◽  
Author(s):  
G. Biedermann ◽  
B. Ott ◽  
K. Rübesam ◽  
F. Maus

Abstract. Title of the paper: Genetic analysis of the population of Vorderwald cattle The actual population of Vorderwald cattle, comprising 5452 animals has been analysed concerning the gene contribution, the generation interval and the degree of relationship and inbreeding with regard of five generations of ancestors. About 84 % of the genes are originating from Vorderwald cattle. The genetic portions of other breeds have been contributed by Red Holsteins, Montbéliards and Ayrshires. The average generation interval parents–current animals is about 4.5 years. The mean relationship has been found out with 5.5 % within the bulls and 3.4 % within the cows. Accordingly the mean coefficient of inbreeding is higher within the bulls (2,7 %) than within the cows (2,4 %). Only 28.6 % of the bulls and 36.6 % of the cows are not inbred. With 0.9 % the increase of inbreeding in the last generation is of alarming proportions; that’s why a carefully directed program of mating has to be recommended.


Author(s):  
Dr. Albert S. Tirkey

Education seeks to develop the innate inner capacities of man. The ultimate goal of education is to prepare the students to be responsible and mentally healthy person to live on this earth. In order to achieve this, students are to be molded only by making them experience the significance of values in the school itself. In most of the cases education takes place under the guidance of teachers. Teachers are the biggest influencers in a student’s life. Their personality and attitudes contribute to a great extend in students learning. In this respect, determining the attitude of prospective teachers towards teaching profession is of great importance. The main objectives of this paper are to test: academic attitude of prospective teachers towards teaching profession; and administrative attitude of prospective teachers towards teaching profession. Tool used for the study was ‘attitude scale towards teaching’, developed by Dr. (Mrs.) Ummen Kulsum. In order to analyze the data, Z-score in terms of standard deviations from the mean was used. The study was delimited to West Garo Hills District of Meghalaya.


2011 ◽  
Vol 54 (1) ◽  
pp. 1-9
Author(s):  
L. Vostrý ◽  
Z. Čapková ◽  
J. Přibyl ◽  
B. Hofmanová ◽  
H. Vostrá Vydrová ◽  
...  

Abstract. In order to estimate effective population size, generation interval and the development of inbreeding coefficients (Fx) in three original breeds of cold-blooded horses kept in the Czech Republic: Silesian Noriker (SN), Noriker (N) and Czech-Moravian Belgian horse (CMB) all animals of the particular breeds born from 1990 to 2007 were analysed. The average values of generation interval between parents and their offspring were: 8.53 in SN, 8.88 in N and 8.56 in CMB. Average values of effective population size were estimated to be: 86.3 in SN, 162.3 in N and 104.4 in CMB. The average values of inbreeding coefficient were 3.13 % in SN stallions and 3.39 % in SN mares, in the N breed 1.76 % and 1.26 % and in the CMB breed 3.84 % and 3.26 % respectively. Overall averages of Fx were: 3.23 %, 1.51 % and 3.55 % for the breeds SN, N and CMB. The average value of inbreeding coefficient Fx increased by 1.22 % in SN, by 0.35 % in N and by 1.01 % in CMB, respectively. This may lead to a reduction in genetic variability. Reduction in genetic variability could be either controlled in cooperation with corresponding populations of cold-blooded breeds in other European countries or controlled by number of sires used in population


Genetics ◽  
1977 ◽  
Vol 86 (3) ◽  
pp. 697-713
Author(s):  
C Chevalet ◽  
M Gillois ◽  
R F Nassar

ABSTRACT Properties of identity relation between genes are discussed, and a derivation of recurrent equations of identity coefficients in a random mating, diploid dioecious population is presented. Computations are run by repeated matrix multiplication. Results show that for effective population size (Ne) larger than 16 and no mutation, a given identity coefficient at any time t can be expressed approximately as a function of (1—f), (1—f)3 and (1—f)6, where f is the mean inbreeding coefficient at time t. Tables are presented, for small Ne values and extreme sex ratios, showing the pattern of change in the identity coefficients over time. The pattern of evolution of identity coefficients is also presented and discussed with respect to N eu, where u is the mutation rate. Applications of these results to the evolution of genetic variability within and between inbred lines are discussed.


2011 ◽  
Vol 45 (4) ◽  
pp. 652-660 ◽  
Author(s):  
Maria Arlene Fausto ◽  
Mariângela Carneiro ◽  
Carlos Maurício F Antunes ◽  
Enrico Antonio Colosimo ◽  
Jorge Andrade Pinto

OBJECTIVE: To evaluate the growth parameters in infants who were born to HIV-1-infected mothers. METHODS: The study was a longitudinal evaluation of the z-scores for the weight-for-age (WAZ), weight-for-length (WLZ) and length-for-age (LAZ) data collected from a cohort. A total of 97 non-infected and 33 HIV-infected infants born to HIV-1-infected mothers in Belo Horizonte, Southeastern Brazil, between 1995 and 2003 was studied. The average follow-up period for the infected and non-infected children was 15.8 months (variation: 6.8 to 18.0 months) and 14.3 months (variation: 6.3 to 18.6 months), respectively. A mixed-effects linear regression model was used and was fitted using a restricted maximum likelihood. RESULTS: There was an observed decrease over time in the WAZ, LAZ and WLZ among the infected infants. At six months of age, the mean differences in the WAZ, LAZ and WLZ between the HIV-infected and non-infected infants were 1.02, 0.59, and 0.63 standard deviations, respectively. At 12 months, the mean differences in the WAZ, LAZ and WLZ between the HIV-infected and non-infected infants were 1.15, 1.01, and 0.87 standard deviations, respectively. CONCLUSIONS: The precocious and increasing deterioration of the HIV-infected infants' anthropometric indicators demonstrates the importance of the early identification of HIV-infected infants who are at nutritional risk and the importance of the continuous assessment of nutritional interventions for these infants.


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