HERITABILITY OF SCROTAL CIRCUMFERENCE IN ONE- AND TWO-YEAR-OLD BULLS OF DIFFERENT BEEF BREEDS

1987 ◽  
Vol 67 (3) ◽  
pp. 645-651 ◽  
Author(s):  
G. H. COULTER ◽  
G. C. KOZUB ◽  
D. R. C. BAILEY ◽  
R. J. MAPLETOFT ◽  
W. F. CATES
Keyword(s):  
Statistical Model ◽  
Key Words ◽  
Fixed Effects ◽  
Performance Test ◽  
Age Groups ◽  
Scrotal Circumference ◽  
Sources Of Variation ◽  
Testicular Size ◽  
Heritability Estimates ◽  
Beef Bulls

Over an 8-yr interval, (1975–1982) scrotal circumference (SC) was measured on 4557 1-yr-old beef bulls from 1796 sires and eight breeds. Measurements were taken upon completion of a 140-d growth performance test. During the period 1977–1983, SC was measured on 7835 2-yr-old beef bulls from 2570 sires and six breeds. Two-year-old bulls were measured during reproductive examinations at spring bull sales. All SC measurements were adjusted for fixed effects of location-year and age, and heritability estimates were calculated within-breed using a paternal half-sib analysis. Heritability estimates for the SC trait in Angus, Charolais, horned Hereford, polled Hereford, Shorthorn, Simmental, Limousin and Maine-Anjou breeds in 1-yr-old bulls were 0.22 ± 0.20, 0.46 ± 0.14, 0.89 ± 0.17, 0.83 ± 0.26, 1.01 ± 0.31, 0.63 ± 0.19, 0.94 ± 0.29 and 0.59 ± 0.22. Heritability estimates for SC in 2-yr-old bulls of the first six breeds were 0.00 ± 0.21, 0.60 ± 0.25, 0.57 ± 0.07, 0.65 ± 0.10, 0.69 ± 0.34 and 0.20 ± 0.24. Owing to the small number of sires or sons within sires for some breed-age groups and the exclusion of some sources of variation in the statistical model, the estimates of heritability may not be precise and should be used to indicate approximate levels of heritability for a particular breed. Key words: Heritability, testicular size, scrotal circumference, beef bulls

TESTICULAR DEVELOPMENT OF SALERS BULLS TO ONE YEAR OF AGE

1988 ◽  
Vol 68 (3) ◽  
pp. 961-964 ◽  
Author(s):  
G. H. COULTER ◽  
D. R. C. BAILEY
Keyword(s):  
Body Weight ◽  
Statistical Model ◽  
Growth Performance ◽  
Key Words ◽  
Performance Test ◽  
Testicular Development ◽  
Scrotal Circumference ◽  
One Year

Scrotal circumference measurements were taken on 255 Salers bulls located at five growth performance test stations at the 56-d (26.9 ± 0.2 cm), 84-d (28.8 ± 0.2 cm) and 140-d weighings (30.8 ± 0.2 cm) in 1986, and on 248 Salers bulls located at four test stations at the 140-d weighing (31.3 ± 0.1 cm) in 1987. The estimated scrotal circumference measurement for Salers bulls at 365 d of age was 29.4 cm. Test station, percentage of Salers breeding within test station, sire of bull within year and test station, and the covariate body weight all contributed to the variance in scrotal circumference measurements. Incorporation of sire of bull within year and test station into the statistical model accounted for a much higher proportion of the variance in scrotal circumference measurements (r2 = 65%) than when percentage of Salers breeding within test station was substituted (r2 = 32%). Key words: Testicular development, scrotal circumference, Salers bulls, recommendations

A comparison of production traits and welfare implications between horned and polled beef bulls

1996 ◽  
Vol 76 (1) ◽  
pp. 1-5 ◽  
Author(s):  
J. M. Stookey ◽  
L. A. Goonewardene
Keyword(s):  
Key Words ◽  
Performance Test ◽  
Average Daily Gain ◽  
Production Traits ◽  
Scrotal Circumference ◽  
Welfare Implications ◽  
Beef Bulls ◽  
Selected Traits ◽  
The University ◽  
Daily Gain

Data from two record of performance test stations (ROP) were used to compare selected traits of polled and horned bulls. The University of Saskatchewan (SASK) ROP test station provided data on 578 Charolais (CH) and 375 Hereford (HE) bulls from 1985 to 1992, while the Alberta (ALTA) Hereford ROP station provided data on 1485 HE bulls from 1985 to 1993. Polled and horned CH bulls from SASK showed similar (P > 0.05) on-test average daily gain (ADG), while polled HE bulls from SASK showed significantly higher (P < 0.03) ADG than their horned counterparts (1.41 ± 0.01 and 1.36 ± 0.02, respectively). Polled CH bulls were 11.4% fatter than horned bulls at the end of the test (P < 0.01). No significant differences in ADG, weight per day of age (WPDA) or scrotal circumference (SC) were observed between polled and homed HE bulls in ALTA. These results show no disadvantage for polled bulls compared to horned for ADG, WPDA, adjusted SC and adjusted yearling weight. From a welfare perspective, it may be advantageous to use polled bulls to circumvent the need for dehorning. Key words: Polled horned bulls ADG test station

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

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.

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

scholarly journals Influence of rearing system on growth of bulls in performance test

2002 ◽  
Vol 18 (1-2) ◽  
pp. 3-10
Author(s):  
Vladan Bogdanovic ◽  
Milan Petrovic
Keyword(s):  
Performance Test ◽  
Growth Traits ◽  
Statistical Significance ◽  
Average Daily Gain ◽  
Test System ◽  
Two Factors ◽  
Origin Group ◽  
Sources Of Variation ◽  
Beef Bulls

Data on 643 beef bulls were used in order to analyze influence of rearing system or herd of origin on growth traits (average daily gain and body masses) of beef bulls in performance test (Marchigiana, n= 181, Chianina, n=240, Romagnola, n=222). Several fixed or random effects, such as breed, type of rearing or herd of origin, group, parity and twinning, were included in two statistical models. According to rearing system (in stall, on pasture or mixed) it should be pointed out that several different sources of variation for growth traits evince statistical significance. Also, herd of origin represents very significant source of variation for all included traits. The main difference between those two factors (type of rearing system or herd of origin) is that influence of rearing system decreased during the test, while the effect of herd of origin remained until the end of test. It was concluded that the adequate determination of non-genetic sources of variation referring to the pre-test system of rearing might be of crucial importance for ranking potential sires.

scholarly journals EFFECT OF MEASUREMENT METHOD, BREED, AND TECHNICIAN ON SCROTAL CIRCUMFERENCE MEASUREMENTS

1986 ◽  
Vol 66 (3) ◽  
pp. 811-815 ◽  
Author(s):  
G. H. COULTER ◽  
G. C. KOZUB ◽  
R. J. MAPLETOFT
Keyword(s):  
Measurement Error ◽  
Key Words ◽  
Variance Components ◽  
Measurement Method ◽  
Error Components ◽  
Scrotal Circumference ◽  
Beef Bulls

Three methods were used by three technicians to measure the scrotal circumference (SC) of three breeds of yearling beef bulls. Variance of an individual SC measurement was affected most by bull. Technician and measurement error components were much smaller. The Society for Theriogenology method of obtaining SC measurements was recommended for use in Canada. Key words: Scrotal circumference, methods, variance components, recommendations

scholarly journals 96 Estimation of the genetic parameters of beef bull semen attributes

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 26-26
Author(s):  
Madison L Butler ◽  
Jennifer M Bormann ◽  
Robert L Weaber ◽  
David M Grieger ◽  
Megan M Rolf
Keyword(s):  
Fixed Effects ◽  
Semen Quality ◽  
Critical Factor ◽  
Production Costs ◽  
Quality Traits ◽  
Forward Selection ◽  
Bull Semen ◽  
Scrotal Circumference ◽  
Beef Bull ◽  
Heritability Estimates

Abstract Fertility is a critical factor in cattle production because it directly relates to producing offspring to offset production costs. A number of semen attributes are believed to affect fertility and are frequently measured as part of routine breeding soundness exams or semen collection procedures. The objective of this study was to estimate the variance components for different semen quantity and quality traits that may influence fertility using phenotypes collected on 369 Simmental bulls. A total of 7,436 bull collection records including volume and concentration were obtained from two bull studs and evaluated utilizing a linear univariate animal model with repeated records. The five-generation pedigree used in the analysis consisted of 3,336 sires and 7,225 dams. Volume is the total amount of ejaculate and measured as milliliters of total ejaculate. Volume measurements ranged from 0.100 to 41.30 milliliters, with an average of 7.599 milliliters. Concentration is a measurement of millions of spermatozoa per milliliter. Concentration measurements ranged from 10 to 3,651 with an average of 1,053 million spermatozoa per milliliter. Fixed effects were included in the model if the effect was significant (P ≤ 0.05) for either backward or forward selection. Fixed effects included bull owner, collection center, location within center, collection day within year as a Julian day, collection year fit as class variables. Fixed effects fit as covariates included age of bull at collection (linear and quadratic), days since previous collection (linear and quadratic), and scrotal circumference (quadratic). Heritability estimates of volume and concentration were 0.43 ± 0.14 and 0.40 ± 0.15. These moderate heritability estimates indicate genetic improvement can be made in beef bull semen quality traits through selection.

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.

Sign in / Sign up

Export Citation Format

Share Document