REGRESSIONS OF PROGENY PROOFS FOR CALVING EASE AND GROWTH ON TEST STATION PERFORMANCE OF CHAROLAIS AND HEREFORD BEEF BULLS

1988 ◽  
Vol 68 (1) ◽  
pp. 107-117
Author(s):  
G. H. CROW ◽  
S. AMAL ◽  
M. DONETZ
Keyword(s):  
Performance Test ◽  
Genetic Correlations ◽  
Monitoring Program ◽  
Error Variance ◽  
Regression Coefficients ◽  
Performance Information ◽  
Calving Ease ◽  
Beef Bulls ◽  
Group Regression ◽  
Score Point

Performance records of 32 Charolais and 52 Hereford beef bulls tested at the Manitoba Bull Test Station for which progeny proofs were available (1984 Canadian Beef Sire Monitoring Program) were analyzed to determine if performance-tested bulls with progeny proofs were representative of the selected group of bulls which were eligible for sale (i.e, had station indexes of 95 or more) and to determine the regressions of progeny proofs on bull performance. The bull performance information included start and end of test weights, interim weights and gains, all expressed as deviations from their respective year-breed contemporary group means. This group of 84 bulls was not significantly different in test gains from the group of all bulls tested over the years 1976–1984 with station indexes of 95 or more. Regressions of progeny proofs for calving ease (CE, in score point units), preweaning gain (WG), yearling gain (YG) and postweaning growth (YG–WG) on bull weights and gains were estimated within breeds, weighting proofs by their prediction error variance. The only significant (P < 0.05) regressions of CE proof on bull performance were for bull weights in the Charolais group. Regression coefficients of WG and YG proofs on bull weights and gains were similar in magnitude with the coefficients for the Hereford breed being significantly different from zero more often than those for the Charolais breed. Effective heritabilities and genetic correlations between bull performance traits and progeny traits were estimated and, for traits defined similarly on parent and progeny, the estimates were similar to literature values. Test station procedures seemed to be effective in that bull performance was an indicator of subsequent progeny performance. Key words: Beef cattle, performance test, progeny test, heritability

GENETIC PARAMETERS FOR MATERNAL TRAITS IN BEEF CATTLE

1988 ◽  
Vol 68 (1) ◽  
pp. 119-128 ◽  
Author(s):  
D. TRUS ◽  
J. W. WILTON
Keyword(s):  
Beef Cattle ◽  
Fixed Effects ◽  
Genetic Correlations ◽  
Monitoring Program ◽  
Parameter Estimates ◽  
Genetic Trend ◽  
Calving Ease ◽  
Modified Method ◽  
Maternal Heritability ◽  
Maternal Grandsire

Direct (D) and maternal (M) parameters for birth weight (BW), preweaning gain (WG) and calving ease (CE) were estimated for Angus (AN), Hereford (HE), Charolais (CH), Simmental (SM) and Shorthorn (SS). Data for the study were collected by Agriculture Canada from 1973 to 1983 for use in the National Sire Monitoring Program. Variances were estimated for each breed by a modified Method IV applied to a sire-maternal grandsire model with herd-year-seasons and age of dam × sex of calf as fixed effects. Genetic correlations (D/M) between D and M effects for WG in AN, HE, SS, CH and SM were −0.54, −0.42, −0.14, −0.26 and −0.45, respectively. Corresponding estimates of direct heritability for WG were 0.39, 0.30, 0.39, 0.27 and 0.43 and of maternal heritability 0.21, 0.27, 0.26, 0.16 and 0.20. Estimates for BW were similar to those for WG. Estimates of the D/M correlation for CE were −0.43, −0.15, −0.32, −0.74 and −0.27, of the direct heritability 0.28, 0.17, 0.19, 0.33 and 0.21, and of the maternal heritability 0.22, 0.13, 0.19, 0.23 and 0.27 for AN, HE, SS, CH and SM, respectively. Genetic trend and the introduction of new genetic lines are expected to have influenced parameter estimates. Due to negative D/M correlation estimates and moderate maternal heritabilities, selection for both the D and M components of maternal traits is advised. Key words: Variance, direct, maternal, heritability, genetic correlation, beef cattle

RELATIONSHIPS OF SCROTAL CIRCUMFERENCE WITH BODY WEIGHT AND BACKFAT THICKNESS IN MULTIBREED SYNTHETIC POPULATIONS OF YOUNG BEEF BULLS

1982 ◽  
Vol 62 (4) ◽  
pp. 1049-1055 ◽  
Author(s):  
A. K. SHARMA ◽  
R. T. BERG
Keyword(s):  
Body Weight ◽  
Performance Test ◽  
Correlation Coefficients ◽  
Backfat Thickness ◽  
Simple Correlation ◽  
Scrotal Circumference ◽  
Synthetic Populations ◽  
Breed Group ◽  
Partial Correlations ◽  
Beef Bulls

Relationships of scrotal circumference (SC) with body weight (BW) and backfat thickness (FT) as measured from scanograms were studied. A total of 935 observations on growing multibreed synthetic beef bulls on a postweaning performance test were available from a commercial herd for this study. Significant breed group, period and group × period interaction effects were noted on SC, BW and FT. BW and SC increased significantly during the test in all breed groups, while FT showed no change in three breed groups. Repeatability pooled across groups for SC was estimated as 0.72; 0.66 after adjusting for BW. Significant correlations were noticed between SC and BW within each breed group. Partial correlations between SC and BW at constant FT were not different from gross correlations. Linear regression coefficients of SC on BW were significant in all groups and showed heterogeneity among groups but not between periods within groups. Adjustments of SC for BW should, therefore, be breed group specific. BW alone accounted for considerable variation in SC, from 38 to 76%. Simple correlation coefficients between SC and FT were low and significant in only two groups. A significant but low positive relationship was noted between SC and FT at constant BW in a group fed a high-concentrate diet during the postweaning gain period, but there was no relationship in four other groups. Results indicated that the method of adjusting SC for FT as an indirect way of adjusting for scrotal fat was not satisfactory. Key words: Bulls, scrotal circumference, growth

The Monitoring Software Design of Performance Test-Bed of Heat Pump Unit

2013 ◽  
Vol 475-476 ◽  
pp. 192-197
Author(s):  
Jian Wen Feng ◽  
Li Peng Wang
Keyword(s):  
Heat Pump ◽  
Performance Test ◽  
Fault Tolerant ◽  
Monitoring Program ◽  
Monitoring Systems ◽  
Air Conditioner ◽  
Test Bed ◽  
Pump Unit ◽  
Heat Pump Unit ◽  
Monitoring Software

Performance test-bed of heat pump unit in central air-conditioner needs the intelligent and multifunctional software. So the monitoring software is designed with a good human-machine interactive interface, based on Visual C# development platform. The software can dynamically configure channels and measurement points to improve the defects of fixed channels for all measuring points in the traditional monitoring systems, which enhanced the flexibility and reliability of system. In order to increase the data accuracy, the improved digital filter algorithm was adopted. In addition, multi-threading mechanism was used to achieve serial communication and data processing, which meets the requirements of monitoring program for multi-tasking and real-time. The results show that monitoring software is powerful, easy to operate, reliable, high fault-tolerant and good user-friendly. It is suitable for using in other monitoring systems.

scholarly journals Comparison of models for estimating genetic parameters and predicting breeding values for birth weight and calving ease in Czech Charolais cattle 

2014 ◽  
Vol 59 (No. 7) ◽  
pp. 302-309 ◽  
Author(s):  
L. Vostrý ◽  
Z. Veselá ◽  
A. Svitáková ◽  
H. Vostrá Vydrová
Keyword(s):  
Animal Model ◽  
Birth Weight ◽  
Beef Cattle ◽  
Fixed Effects ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Genetic Effects ◽  
Parameters Estimation ◽  
Calving Ease ◽  
Heritability Estimates

The most appropriate model for genetic parameters estimation for calving ease and birth weight in beef cattle was selected. A total of 27 402 field records were available from the Czech Charolais breed. For estimation of genetic parameters for calving ease and body weight, three bivariate models were tested: a linear-linear animal model (L-LM) with calving ease classified into four categories (1 &ndash; easy; 2&ndash;4 &ndash; most difficult), a linear-linear animal model (SC-LM) in which calving ease scores were transformed into Snell scores (Snell 1964) and expressed as percentage of assisted calving (ranging 0&ndash;100%), and a bivariate threshold-linear animal model (T-LM) with calving ease classified into four categories (1 &ndash; easy, 2&ndash;4 &ndash; most difficult). All tested models included fixed effects for contemporary group (herd &times; year &times; season), age of dam, sex and breed of a calf. Random effects included direct and maternal genetic effects, maternal permanent environmental effect, and residual error. Direct heritability estimates for calving ease and birth weight were, with the use of L-LM, SC-LM, and T-LM, from 0.096 &plusmn; 0.013 to 0.226 &plusmn; 0.024 and from 0.210 &plusmn; 0.024 to 0.225 &plusmn; 0.026, respectively. Maternal heritability estimates for calving ease and birth weight were, with the use of L-LM, SC-LM, and T-LM, from 0.060 &plusmn; 0.031 to 0.104 &plusmn; 0.125 and from 0.074 &plusmn; 0.041 to 0.075 &plusmn; 0.040, respectively. Genetic correlations of direct calving ease with direct birth weight ranged from 0.46 &plusmn; 0.06 to 0.50 &plusmn; 0.06 for all tested models; whereas maternal genetic correlations between these two traits ranged from 0.24 &plusmn; 0.17 to 0.25 &plusmn; 0.53. Correlations between direct and maternal genetic effects within-trait were negative and substantial for all tested models (ranging from &ndash;0.574 &plusmn; 0.125 to &ndash;0.680 &plusmn; 0.141 for calving ease and from &ndash;0.553 &plusmn; 0.122 to &ndash;0.558 &plusmn; 0.118 for birth weight, respectively), illustrating the importance of including this parameter in calving ease evaluations. Results indicate that any of the tested models could be used to reliably estimate genetic parameters for calving ease for beef cattle in the Czech Republic. However, because of advantages in computation time and practical considerations, genetic analysis using SC-LM (transformed data) is recommended.

Correlations between food intake in young bulls and production, fertility and health disorders in lactating dairy cattle

1999 ◽  
Vol 24 ◽  
pp. 153-158
Author(s):  
R. Wassmuth ◽  
D. Boelling ◽  
J. Jensen
Keyword(s):  
Food Intake ◽  
Dairy Cattle ◽  
Milk Yield ◽  
Performance Test ◽  
Selection Process ◽  
Disease Incidence ◽  
Genetic Correlations ◽  
Calving Interval ◽  
Black And White ◽  
Heritability Estimates

AbstractDisease incidence in dairy cattle is to be reduced for animal welfare and economical reasons. This should be achieved not only by improvement of management but preferably also by genetic means. This study looks at the possibility of decreasing disease incidence in first lactation cows by increasing food intake. The latter is not measured on the cows directly but on young bulls during their performance test. Data consisted of 2203 Danish Red, 4527 Danish Black and White and 1022 Danish Jersey potential AI-bulls and 56 494 Danish Red, 264107 Danish Black and White and 57 661 Danish Jersey first lactation cows. Measures of food intake were provided by two Danish performance test stations. Information on incidence of mastitis, retained placenta, metritis, sole ulcer and ketosis as well as calving interval and energy corrected milk yield of first lactation cows was based on data extracted from the national data base in Denmark. Genetic (co)variances were estimated using restricted maximum likelihood. Heritability estimates of disease incidence and calving interval were low, ranging from <0.01 to 0.13 depending on breed. Heritability estimates of energy corrected milk yield were in the range of 0.28 to 0.33. In all breeds, an unfavourable genetic relationship between milk yield and disease incidence was found, while genetic correlations between food intake and ketosis were favourable, ranging between -0.03 and -0.25. Fertility disorders had an inconsistent correlation with food intake traits across breeds. Food intake of bulls could be included in the selection process in order to avoid nutrition-related disorders like ketosis.

Genetic correlations among indicator traits for carcass composition measured in yearling beef bulls and finished feedlot steers

2005 ◽  
Vol 85 (4) ◽  
pp. 463-473 ◽  
Author(s):  
R. Bergen ◽  
S. P. Miller ◽  
J. W. Wilton
Keyword(s):  
Genetic Correlation ◽  
Carcass Traits ◽  
Genetic Correlations ◽  
Carcass Composition ◽  
Carcass Weight ◽  
Muscle Size ◽  
Longissimus Muscle ◽  
Muscle Area ◽  
Feedlot Steers ◽  
Beef Bulls

Genetic correlations were examined among 10 live growth and ultrasound traits measured in yearling beef bulls (n = 2172) and four carcass traits measured in crossbred finished feedlot steers (n = 1031). Heritabilities ranged from 0.13 (bull ultrasound longissimus muscle width) to 0.83 (yearling bull hip height). Genetic correlations indicated that selecting yearling bulls for increased growth rate and hip height would lead to higher carcass weight, increased longissimus muscle area and reduced levels of carcass marbling in steers. Bull ultrasound fat depth was positively associated with both carcass fat depth and marbling score. Most ultrasound longissimus muscle size measurements in bulls were positively associated with each other and with carcass longissimus muscle area in steers, but the magnitude of the genetic correlation with carcass measurements depended on the bull longissimus muscle size trait in question. This suggests that longissimus muscle shape in bulls may be related to carcass weight, fat and muscle traits in steers. Results confirm that while ultrasound is a valuable tool for the genetic improvement of carcass traits in beef cattle, genetic correlations between live bull ultrasound and steer carcass traits less then unity suggest that selection would benefit from multiple trait evaluations in situations where reliable carcass data are available. Key words: Ultrasound, beef carcass, heritability, genetic correlation

Genetic parameters for calving difficulty using complex genetic models in five beef breeds in Australia

2016 ◽  
Vol 56 (5) ◽  
pp. 927 ◽  
Author(s):  
M. G. Jeyaruban ◽  
D. J. Johnston ◽  
B. Tier ◽  
H.-U. Graser
Keyword(s):  
Genetic Parameters ◽  
Linear Models ◽  
Random Effect ◽  
Genetic Correlations ◽  
Genetic Effect ◽  
Genetic Effects ◽  
Gestation Length ◽  
Calving Ease ◽  
Direct Genetic Effect ◽  
Calving Difficulty

Data on Angus (ANG), Charolais (CHA), Hereford (HER), Limousin (LIM) and Simmental (SIM) cattle were used to estimate genetic parameters for calving difficulty (CD), birthweight (BWT) and gestation length (GL) using threshold-linear models and to examine the effect of inclusion of random effect of sire × herd interaction (SxH) in the models. For models without SxH, estimated heritabilities for direct genetic effect of CD were 0.24 (±0.02), 0.22 (±0.04), 0.31 (±0.02), 0.22 (±0.04) and 0.17 (±0.01) for ANG, CHA, HER, LIM and SIM, respectively, whereas maternal heritabilities ranged from 0.13 to 0.20. Estimated heritabilities for direct genetic effect of BWT were 0.38 (±0.01), 0.37 (±0.03), 0.46 (±0.01), 0.35 (±0.02) and 0.36 (±0.01) for ANG, CHR, HER, LIM and SIM, respectively, whereas maternal heritabilities ranged from 0.08 to 0.11. Estimated heritabilities for direct genetic effect of GL were 0.59 (±0.02), 0.42 (±0.04), 0.50 (±0.03), 0.45 (±0.04) and 0.42 (±0.03) for ANG, CHR, HER, LIM and SIM, respectively, whereas maternal heritabilities ranged from 0.03 to 0.09. Genetic correlations between direct genetic effects of CD with BWT were highly positive and with GL were moderately positive for all five breeds. Estimated genetic correlations between direct genetic effects and maternal genetic effects (rdm) ranged across the five breeds from –0.40 (±0.05) to –0.16 (±0.02), –0.41 (±0.03) to –0.27 (±0.08) and –0.47 (±0.10) to –0.06 (±0.12) for BWT, GL and CD, respectively. Fitting SxH interaction as additional random effect significantly increased the log-likelihood for analyses of BWT, GL and CD of all breeds, except for GL of CHA. The estimated heritabilities were less than or equal to the estimates obtained with models omitting SxH. The rdm increased (i.e. became less negative) for BWT, GL and CD of all five breeds. However, the increase for GL was not substantially high in comparison to the increase observed for BWT and CD. Genetic parameters obtained for BWT, GL and CD, by fitting SxH as an additional random effect, are more appropriate to use in the genetic evaluation of calving ease in BREEDPLAN.

EVALUATION OF BEEF SIRES ACROSS BREEDS FOR CALVING EASE

1977 ◽  
Vol 57 (4) ◽  
pp. 635-645 ◽  
Author(s):  
L. R. SCHAEFFER ◽  
J. W. WILTON
Keyword(s):  
Maximum Likelihood ◽  
Scoring System ◽  
Variance Components ◽  
Error Variance ◽  
Best Linear Unbiased Prediction ◽  
Linear Unbiased Prediction ◽  
Calving Ease ◽  
Best Linear Unbiased ◽  
Maximum Likelihood Prediction ◽  
Unbiased Prediction

Agriculture Canada and Alberta Record of Performance calving ease records on 54,139 calves from 3,338 sires of 18 breeds were used to evaluate sires by comparisons across breeds of sire. An objective scoring system was applied to the calving ease codes to derive appropriate weights for each category rather than using percentage of unassisted births or assuming equal intervals between categories. Common sire and error variance components were assumed for all breeds of sire. Heritability of calving ease under the model used was estimated to be.10 by maximum likelihood. Prediction of sire values for calving ease scores of future calves were calculated by best linear unbiased prediction procedures. Shorthorn, Hereford, and Angus sires caused relatively few calving difficulties, while Maine-Anjou sires caused more difficulties. Age of dam and sex of calf differences were also important. The range of sire evaluations for calving ease was narrow, but the bulls in either extreme could be identified.

The genetic foundation of fitness and reproduction traits in Australian pig populations. 2. Relationships between weaning to conception interval, farrowing interval, stayability, and other common reproduction and production traits.

1996 ◽  
Vol 47 (8) ◽  
pp. 1275 ◽  
Author(s):  
E Tholen ◽  
KL Bunter ◽  
S Hermesch ◽  
HU Graser
Keyword(s):  
Genetic Parameters ◽  
Performance Test ◽  
Genetic Relationships ◽  
Average Daily Gain ◽  
Genetic Correlations ◽  
Data Sets ◽  
Production Traits ◽  
Breeding Programs ◽  
Reproduction Traits ◽  
Daily Gain

Data sets from 2 large Australian piggeries were used to estimate genetic parameters for the traits weaning to conception interval (WCIi-l,i) and farrowing interval (FIi-l,i), number born alive (NBAI), average piglet birthweight (BWi), 21-day litter weight (W21i), and sow stayability (STAYli) recorded for each ith parity, as well as sow average daily gain (ADG) and backfat (BF) recorded at the end of performance test. Over parities and herds, heritabilities for each trait were in the ranges: WCI/FI, 0.0-0.10; NBA, 0.09-0.16; BW, 0.11-0.35; W21, 0.12-0.23; STAYli, 0.02-0.09; ADG, 0.35-0.37; BF, 0.36-0.45. Genetic correlations between NBAl and NBA from later parities were significantly different from 1. In addition, in 1 herd negative genetic correlations (rg = -0.04 to -0.25) were found between sow stayability traits and NBA1, but not NBA recorded in later parities. Stayability was Unfavourably correlated with ADG and BF, and favourably correlated with WCI12. However, WCI12 was unfavourably correlated genetically with BF (rg = -0.24) but uncorrelated with ADG. Antagonistic relationships also existed between NBA and BW, NBA and W21, and BW and STAY. In addition to the traditional traits currently included in pig-breeding programs (e.g. ADG, BF, and NBA), traits such as WCI, BW, and STAY should also be considered as selection criteria to minimise the detrimental effects of antagonistic genetic relationships between traits.

Influence of performance testing on reproductive performance of beef bulls

1992 ◽  
Vol 72 (1) ◽  
pp. 23-30
Author(s):  
J. W. Wilton ◽  
M. R. McMorris
Keyword(s):  
Reproductive Performance ◽  
Performance Test ◽  
Performance Testing ◽  
Test Program ◽  
Improvement Program ◽  
Scrotal Circumference ◽  
Subsequent Fertility ◽  
Beef Bulls ◽  
Calving Season

The fertility of beef bulls which completed performance test in the Ontario Bull Test Program was measured by classification of success as breeders according to surveys of consignors to test, by classification of satisfaction in surveys of users of tested bulls and by measurement of calf crop percentages and birth dates of progeny relative to herdmates in the Ontario Beef Herd Improvement Program. Consignors classified 3.0% of the 2556 bulls with completed information as unsuccessful breeders. Users rated 61.5% of the 411 bulls with information from the participant survey as very satisfactory and 4.5% as very unsatisfactory. The effects of end of test weight, gain index, backfat and scrotal circumference on calf crop percentage (cows calving relative to cows exposed), percent of calves born in the first 3 wk of the calving season, percent of calves born in the first 12 wk and satisfaction score were generally small and nonsignificant as tested within breed for 122 Angus, 451 Charolais, 632 Hereford, 575 Limousin and 501 Simmental bulls. In general, gain on test and end-of-test measurements were not found to have any association with subsequent fertility of bulls tested. There was no evidence that increased scrotal circumferences were associated with increased measures of productive performance nor that increased fatness, within the range included in the Ontario Bull Test Program, decreased reproductive performance. Key words: Fertility, genetic evaluation, scrotal circumference, backfat

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