ADDITIVE AGE OF DAM ADJUSTMENT FACTORS FOR WEANING WEIGHT OF BEEF CATTLE

1980 ◽  
Vol 60 (1) ◽  
pp. 11-19 ◽  
Author(s):  
A. K. W. TONG ◽  
J. A. NEWMAN
Keyword(s):  
Beef Cattle ◽  
Random Effects ◽  
Fixed Effects ◽  
Mean Square ◽  
Weaning Weight ◽  
Adjustment Factors ◽  
Interaction Term ◽  
Breed Crosses ◽  
Weight For Age

A study of 373 351 weaning weight records from the National and the Alberta Provincial Record of Performance programs for beef cattle, representing 279 061 cows from 5421 herds during the period 1971 through 1977, was used to examine age of dam by breed of sire interactions and to derive a set of additive age of dam adjustment factors for calf weaning weight. The model included fixed effects due to age of dam–sex of calf–breed of dam subclasses, breed of sire, age of dam–breed of sire interactions and year of calving plus random effects due to herds and cows within herds. A relatively small age of dam–breed of sire interaction mean square indicated that one set of adjustment factors could be used for calves from all the breeds of sire, even though the interaction term was statistically significant (P < 0.005). A set of additive factors to adjust calf weaning weight for age of dam within sex of calf and breed of dam are presented for the following breeds and breed crosses of dam: Angus, Charolais, Hereford, Shorthorn, British breed crosses, half Charolais–half British, half Simmental–half British and "others."

1 Effect of Conditioning, Rest, and Post-rest Transport Duration on Welfare Indicators of Beef Cattle Transported by Road

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 2-3
Author(s):  
Daniela M Melendez ◽  
Sonia Marti ◽  
Timothy D Schwinghamer ◽  
Derek B Haley ◽  
Karen S Schwartzkopf-Genswein
Keyword(s):  
Beef Cattle ◽  
Factorial Design ◽  
Random Effects ◽  
Fixed Effects ◽  
Rest Period ◽  
Flight Speed ◽  
Beef Calves ◽  
Welfare Indicators ◽  
Preliminary Results ◽  
And Performance

Abstract The aim of this study was to assess the effects of conditioning, rest, and post-rest transport duration on welfare indicators of 6–7 mo old beef calves. Three hundred and twenty-eight weaned calves (237 ± 29.7 kg BW) were randomly assigned to a 2 × 2 × 2 nested factorial design: conditioning, conditioned (C) or non-conditioned (N); rest, 0 (R0) or 8 (R8) h, and post-rest transport, 4 (T4) or 15 (T15) h. Calves were sampled prior to the first loading (L1), after 20h of transport, prior to and after the additional 4 or 15-h transport, and at 1, 2, 3, 5, 14, and 28 d after transport ended. Data were analyzed using the GLIMMIX procedure of SAS. Fixed effects included conditioning, transport and time nested within rest period, while random effects included animal and pen. Greater shrink (P &lt; 0.01) was observed in C than N calves after the initial 20-h transport. The N calves had greater (P &lt; 0.01) ADG than C calves between L1 and d 5, while C had greater (P &lt; 0.01) ADG than N calves between 14 and 28 d. L-lactate concentrations and flight speed were greater (P ≤ 0.05) in C than N calves between L1 and d 5. The R8-T4 calves had greater (P &lt; 0.01) ADG than R8-T15 calves between L1 and d 5. The R0-T4 calves had greater (P = 0.02) L-lactate concentrations than R0-T15 and R8-T4 calves on d 1. The R0 calves had greater (P &lt; 0.01) ADG than R8 calves between 14 and 28 d. Preliminary results show physiological, behavioral, and performance differences across treatments, however, additional indicators are required to accurately assess the effect of conditioning, rest, and post-rest transport durations on calf welfare.

PSIII-8 Genetic Parameter Estimates for Bull Prolificacy and Its Relationship with Scrotal Circumference in a Commercial Beef Cattle Population

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 158-159
Author(s):  
Chad A Russell ◽  
E J Pollak ◽  
Matthew L Spangler
Keyword(s):  
Beef Cattle ◽  
Breeding Season ◽  
Random Effects ◽  
Fixed Effects ◽  
Genetic Parameter ◽  
Additive Genetic Effect ◽  
Parameter Estimates ◽  
Contemporary Group ◽  
Scrotal Circumference ◽  
Heritability Estimates

Abstract The commercial beef cattle industry relies heavily on the use of natural service sires. Either due to the size of breeding herds or to safe-guard against injury during the breeding season, multiple-sire breeding pastures are utilized. Although each bull might be given an equal opportunity to produce offspring, evidence suggest that there is substantial variation in the number of calves sired by each bull in a breeding pasture. DNA-based paternity assignment enables correct assignment of calves to their respective sires in multi-sire pastures and presents an opportunity to investigate the degree to which this trait complex is under genetic control. Field data from a large commercial ranch were used to estimate genetic parameters for calf count (CC; n=623) and yearling scrotal circumference (SC; n=1962) using univariate and bivariate animal models. Average CC and SC were 12.1±11.1 calves and 35.4±2.30 cm, respectively. Average number breeding seasons per bull and bulls per contemporary group were 1.40 and 24.9, respectively. The model for CC included fixed effects of age during the breeding season (in years) and contemporary group (concatenation of breeding pasture and year). Random effects included additive genetic and permanent environmental effects, and a residual. The model for SC included fixed effects of age (in days) and contemporary group (concatenation of month and year of measurement). Random effects included an additive genetic effect and a residual. Univariate model heritability estimates for CC and SC were 0.237±0.156 and 0.456±0.072, respectively. Similarly, the bivariate model resulted in heritability estimates for CC and SC of 0.240±0.155 and 0.461±0.072, respectively. Repeatability estimates for CC from univariate and bivariate models were 0.517±0.054 and 0.518±0.053, respectively. The estimate of genetic correlation between CC and SC was 0.270±0.220. Parameter estimates suggest that both CC and SC would respond favorably to selection and that CC is moderately repeatable.

EFFECTS OF YEARLING WEIGHT SELECTION IN SHORTHORN BEEF CATTLE ON AGE-OF-DAM ADJUSTMENT FACTORS

1990 ◽  
Vol 70 (3) ◽  
pp. 963-965
Author(s):  
J. C. OLTHOFF ◽  
G. H. CROW ◽  
G. W. RAHNEFELD
Keyword(s):  
Birth Weight ◽  
Beef Cattle ◽  
Key Words ◽  
Selection Line ◽  
Weaning Weight ◽  
Performance Change ◽  
Adjustment Factors ◽  
Over Time

Lines within a breed which differ in their level of performance may require different age-of-dam adjustment factors in the same way that different breeds do. Age-of-dam adjustments calculated from a control and a yearling weight selection line indicated lower values in the selected line for calf birth weight, weaning weight and yearling weight for 2- and 4-yr-old dams. Trends for adjustment factors in each line over time were generally not significant but tended to diverge. Age-of-dam adjustment factors within a breed may need to be reevaluated at intervals as levels of performance change. Key words: Beef cattle, age of dam adjustment, selection, yearling weight

scholarly journals Selection of a suitable data set and model for the estimation of genetic parameters of the weaning weight in beef cattle

2007 ◽  
Vol 50 (6) ◽  
pp. 562-574
Author(s):  
L. Vostrý ◽  
J. Přibyl ◽  
Z. Veselá ◽  
V. Jakubec
Keyword(s):  
Beef Cattle ◽  
Fixed Effects ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Genetic Effect ◽  
Suitable Model ◽  
Data Set ◽  
Weaning Weight ◽  
Estimation Of Genetic Parameters ◽  
Selection Of

Abstract. The objective of this paper was to select a suitable data subset and statistical model for the estimation of genetic parameters for weaning weight of beef cattle in the Czech Republic. Nine subsets were tested for the selection of a suitable subset. The subsets differed from each other in the limit of sampling criteria. The most suitable subset satisfied these conditions: at least 5 individuals per each sire, 5 individuals per HYS (herd, year, season), 2 sires per HYS, and individuals per dams that have at least one half-sister and two offspring (n = 4 806). The selection of a suitable model was carried out from 10 models. These models comprised some of the random effects: direct genetic effect, maternal genetic effect, permanent maternal environment effect, HYS, sire × herd or sire × year interaction, and some of the fixed effects: dam’s age, sex (young bull, heifer × single, twin born), HYS, year, herd. The direct heritability (h2a) ranged from 0.06 to 0.17, of maternal heritability (h2m) from 0.03 to 0.06. The genetic correlations between the direct and maternal effect (ram) were in the range of –0.15 –0.42.

SEX OF CALF AND AGE OF DAM ADJUSTMENTS FOR SOME PERFORMANCE TRAITS IN TWO POPULATIONS OF BEEF CATTLE

1982 ◽  
Vol 62 (3) ◽  
pp. 699-708 ◽  
Author(s):  
A. K. SHARMA ◽  
L. WILLMS ◽  
R. T. HARDIN ◽  
R. T. BERG
Keyword(s):  
Birth Weight ◽  
Beef Cattle ◽  
Least Squares ◽  
Key Words ◽  
Weaning Weight ◽  
Adjustment Factors ◽  
Main Effects ◽  
Two Populations ◽  
Age And Sex ◽  
Methods Of Application

Sex of calf and age of dam effects on birth weight, preweaning ADG, 180-day weaning weight; and age of dam effects on yearling weight, postweaning ADG in males, and 18-mo weight in females were studied in a Hereford and a beef Synthetic population. The effects of breed, sex of calf, age of dam and year were significant on preweaning traits. The superior milking ability of Synthetic cows over Herefords was more pronounced for male than female calves. Additive and multiplicative adjustment factors were calculated from the least squares analyses. Additive adjustments for age of dam and multiplicative adjustments for sex of calf were found most suitable for preweaning traits. Three methods of application of adjustment factors were studied. Multiplicative sex of calf adjustment followed by additive age of dam adjustment was found to be most effective as indicated by the reductions in mean squares for main effects and interactions. Additive and multiplicative age of dam factors are presented for yearling weight in males and 18-mo weight in females. Use of additive factors is recommended. Extending weaning weight age of dam adjustments for postweaning traits was not found suitable in this study. Key words: Beef cattle, age and sex, adjustment factors

Adjusting scrotal circumference of yearling beef bulls in five composites

1996 ◽  
Vol 76 (2) ◽  
pp. 189-191 ◽  
Author(s):  
D. D. Kress ◽  
K. C. Davis ◽  
M. W. Tess
Keyword(s):  
Birth Weight ◽  
Low Birth Weight ◽  
Beef Cattle ◽  
Key Words ◽  
Fixed Effects ◽  
Linear Quadratic ◽  
Scrotal Circumference ◽  
Adjustment Factors ◽  
Significant Regression ◽  
Linear Regressions

Records from five composite strains of beef cattle were used to estimate age of dam and age of bull adjustment factors for scrotal circumference of yearling bulls. Data were obtained from Beefbooster Cattle Alberta Ltd., Calgary, AB. There were 5244 scrotal circumference records on yearling bulls born from 1987 to 1992. M1, M2, and M4 were maternal composites selected primarily for weaning weight, M3 was a terminal composite selected primarily for low birth weight, and TX was a terminal composite selected primarily for feedlot gain. The prominent foundation breeds were Angus for M1, Hereford for M2, various small breeds for M3, Limousin and Gelbvieh for M4, and Charolais for TX. Statistical analyses were performed for each composite separately according to the model that included the fixed effects of herd, year, age of dam and linear (quadratic was not significant) regression on age of bull at measurement. Average age at measurement was 340, 333, 361, 358, and 375 d for M1, M2, M3, M4, and TX, respectively, and range in age was about 100 d for most composites. Age of dam was significant for all composites except M4. Linear regressions on age of bull were 0.0376, 0.0379, 0.0308, 0.0410, and 0.0349 cm d−1 for M1, M2, M3, M4, and TX, respectively. Scrotal circumference of composite bulls should be adjusted additively for age of dam and linearly for age of bull. These adjustments tended to be smaller for age of dam and larger for age of bull than those reported for straighbred or purebred bulls. Key words: Beef cattle, composites, scrotal circumference, adjustment factors

scholarly journals Genetic parameter estimates for bull prolificacy and its relationship with scrotal circumference in a commercial beef cattle population

2021 ◽  
Author(s):  
C A Russell ◽  
E J Pollak ◽  
M L Spangler
Keyword(s):  
Beef Cattle ◽  
Breeding Season ◽  
Random Effects ◽  
Fixed Effects ◽  
Genetic Parameter ◽  
Additive Genetic Effect ◽  
Parameter Estimates ◽  
Contemporary Group ◽  
Scrotal Circumference ◽  
Heritability Estimates

Abstract The commercial beef cattle industry relies heavily on the use of natural service sires. When artificial insemination is deemed difficult to implement, multi-sire breeding pastures are used to increase reproductive rates in large breeding herds or to safe-guard against bull injury during the breeding season. Although each bull might be given an equal opportunity to produce offspring, evidence suggest that there is substantial variation in the number of calves sired by each bull in a breeding pasture. With the use of DNA-based paternity testing, correctly assigning calves to their respective sires in multi-sire pastures is possible and presents an opportunity to investigate the degree to which this trait complex is under genetic control. Field data from a large commercial ranch was used to estimate genetic parameters for calf count (CC; 574 records from 443 sires) and yearling scrotal circumference (SC; n=1961) using univariate and bivariate animal models. Calf counts averaged 12.2±10.7 and SC averaged 35.4±2.30 cm. Bulls had an average of 1.30 records and there were 23.9±11.1 bulls per contemporary group. The model for CC included fixed effects of age during the breeding season (in years) and contemporary group (concatenation of breeding pasture and year). Random effects included additive genetic and permanent environmental effects, and a residual. The model for SC included fixed effects of age (in days) and contemporary group (concatenation of month and year of measurement). Random effects included an additive genetic effect and a residual. Univariate model heritability estimates for CC and SC were 0.178±0.142 and 0.455±0.072, respectively. Similarly, the bivariate model resulted in heritability estimates for CC and SC of 0.184±0.142 and 0.457±0.072, respectively. Repeatability estimates for CC from univariate and bivariate models were 0.315±0.080 and 0.317±0.080, respectively. The estimate of genetic correlation between CC and SC was 0.268±0.274. Heritability estimates suggest that both CC and SC would respond favorably to selection. Moreover, CC is lowly repeatable and although favorably correlated, SC appears to be weakly associated with CC.

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