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

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

1990 ◽  
Vol 70 (3) ◽  
pp. 963-965
Author(s):  
J. C. OLTHOFF ◽  
G. H. CROW ◽  
G. W. RAHNEFELD

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


1983 ◽  
Vol 63 (1) ◽  
pp. 7-15
Author(s):  
A. K. W. TONG

A subset of birth weight records consisting of 191 535 calves, from 7021 herd-years with fewer than 50% estimated weights, tested during 1971 through 1980 was selected from the data files of the Federal-Provincial Record of Performance program for beef cattle to estimate breed averages and age of dam adjustment factors. The main effects included herd-years, breed of sire, breed of dam, sex of calf and age of dam. The interaction effects for breed of sire by sex of calf on birth weight were significant (P < 0.01) and the estimated differences for 22 breeds of sire expressed as deviations from the Hereford breed ranged from − 4.05 to 6.27 kg for male calves and from − 3.70 to 6.20 kg for female calves. The effects of breed of dam, sex of calf, age of dam and all the two-way interactions were significant at P < 0.01, while the three-way interaction was significant at P < 0.05. Additive age of dam adjustment factors within sex of calf were derived for 12 breeds of dam. The general age of dam effects averaged over breed of sire and breed of dam, expressed as deviations from the mature dams, were − 2.69, − 1.27, − 0.41, 0 kg for male calves, and − 2.64, − 1.26, − 0.50, 0 kg for female calves from 2-, 3-, 4-, and 5 + yr-old dams. Key words: Birth weight, breed averages, age of dam adjustment factors


2011 ◽  
Vol 50 (No. 1) ◽  
pp. 14-21 ◽  
Author(s):  
E. Krupa ◽  
M. Oravcová ◽  
P. Polák ◽  
J. Huba ◽  
Z. Krupová

Growth traits of purebred calves of six beef breeds (Aberdeen Angus &ndash; AA, Blonde d&rsquo;Aquitaine &ndash; BA, Charolais &ndash; CH,Hereford &ndash; HE, Limousine &ndash; LI and Beef Simmental &ndash; BS) born from 1998 to 2002 were analysed. Traits under study were birth weight (BW), weight at 120 days (W120), weight at 210 days &ndash; weaning weight (WW), weight at 365 days &ndash; yearling weight (YW) and average daily gains from birth to 120 days (ADG1), from birth to 210 days (ADG2), from birth to 365 days (ADG3), from 120 to 210 days (ADG4). General linear model with class effects of breed, dam&rsquo;s age at calving, sex, herd-year-season (HYS) and covariation of age at weighing was used for analyses. All effects significantly affected both weight and gain traits except for dam&rsquo;s age that was significant for BW, W120, YW and ADG3, and age at weighing that was significant for W120, WW, YW, ADG2, ADG3, ADG4. Estimated least squares means of growth traits were compared using Scheffe&rsquo;s multiple-range tests. Highest BW (40.57&nbsp;kg) and W120 (172.43 kg) were found for BA calves. BS calves had highest WW (260.30 kg), YW (424.07 kg), ADG1 (1&nbsp;154&nbsp;g), ADG2 (1 053 g), ADG3 (1 054 g) and ADG4 (1 098 g). Highest BW, YW, ADG3 and ADG4 were found for males-singles. Males-twins had highest W120, WW, ADG1 and ADG2. Calves descending from 5&ndash;7 years old dams had highest BW, W120, WW, ADG1, ADG2 and ADG4. The proportion of variability of growth traits explained by HYS effect (42.96&ndash;71.69%) was high, whereas proportions of variability explained by SEX effect (2.03&ndash;5.77%), age of dam (1.02&ndash;2.24%) and breed (1.05&ndash;2.21%) were low. Residuals accounted for 23.71 up to 53.79% of total variance. &nbsp;


1982 ◽  
Vol 62 (1) ◽  
pp. 287-290
Author(s):  
D. K. AARON ◽  
F. A. THRIFT

Birth and weaning weight data were evaluated on 1/2 Simmental (SH, SA), 1/2 Maine-Anjou (MH, MA), 3/4 Simmental (S.SH, S.SA) and 3/4 Maine-Anjou (M.MH, M.MA) calves. For birth weight, 1/2 Simmental calves were lighter (P < 0.01) than 1/2 Maine-Anjou calves, and calves from Hereford cows were heavier (P < 0.01) than calves from Angus cows. Also, S.SH calves were heavier (P < 0.01) than S.SA calves. For weaning weight, 3/4 Simmental calves were heavier (P < 0.01) than 3/4 Maine-Anjou calves, and 1/2 Simmental and Maine-Anjou calves were lighter (P < 0.01) than 3/4 Simmental and Maine-Anjou calves. Key words: Calf genetic types, grading-up, beef cattle


1996 ◽  
Vol 76 (2) ◽  
pp. 189-191 ◽  
Author(s):  
D. D. Kress ◽  
K. C. Davis ◽  
M. W. Tess

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


2021 ◽  
Vol 3 (2) ◽  
pp. 117-123
Author(s):  
S. A. Adeyanju ◽  
O. Akinokun ◽  
O. O. Ariyibi

Data on birth weight, preweaning daily rate of gain and weaning weight of Ndama beef cattle were obtained from routine records kept on the Fashola Livestock Farm between 1959 and 1964 and subjected to least-squares analysis to determine the effects of sex, month, year and sire on the performance characteristics. The results indicated that the Ndama weighed 16.95 kg at birth and 97.61 kg at weaning when adjusted to 205 days with a preweaning daily weigh gain of 0.38 kg. The bulls were significantly heavier at birth and weaning and also had a significantly higher preweaning daily weight gain than the heifers. Birth weight, preweaning daily rate of gain, and weaning weight showed significant sex, month, year and sire effects


2009 ◽  
Vol 87 (10) ◽  
pp. 3089-3096 ◽  
Author(s):  
L. M. Melucci ◽  
A. N. Birchmeier ◽  
E. P. Cappa ◽  
R. J. C. Cantet

1993 ◽  
Vol 73 (4) ◽  
pp. 971-975 ◽  
Author(s):  
G. W. Rahnefeld ◽  
Doug Ward ◽  
G. M. Weiss

The following were compared as measures of cow productivity: (A) calf weaning weight per mating opportunity; (B) calf weaning weight per mating opportunity with cow weight at weaning as a covariate; (C) calf weaning weight per mating opportunity per unit of cow weight at weaning; and (D) calf weaning weight per mating opportunity per cow metabolic weight (kg0.75) at weaning. Results indicate that the method described under (C) is best at reducing error followed closely by the method described under (D). The least satisfactory measure of cow productivity was (B). Key words: Beef cattle, cow efficiency, productivity


2000 ◽  
Vol 80 (1) ◽  
pp. 191-193
Author(s):  
J. J. Tosh ◽  
R. A. Kemp

Genetic trends for weaning weight were determined in two herds of multibreed beef cattle that originated from a common base and were subject to mutual breeding policies in separate environments. The herds diverged for the direct though not the maternal genetic component of weaning weight within the 13-yr period examined; in the final year, the difference (P < 0.001) between the herds was almost 3 kg. This could have been partly due to unequal selection differentials and generation intervals. Results suggested the extent of natural selection also differed between the two environments. Key words: Beef cattle, crossbreeding, genetic trends, selection, weaning weight


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