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Comparison Of Different Functions To Describe Growth From Weaning To Maturity In Crossbred Beef Cattle, Madeline J. Zimmermann, Larry A. Kuehn, Matthew L. Spangler, R. Mark Thallman, Warren M. Snelling, Ronald M. Lewis
Comparison Of Different Functions To Describe Growth From Weaning To Maturity In Crossbred Beef Cattle, Madeline J. Zimmermann, Larry A. Kuehn, Matthew L. Spangler, R. Mark Thallman, Warren M. Snelling, Ronald M. Lewis
Department of Animal Science: Faculty Publications
Cow mature weight (MWT) has increased in the past 30 yr. Larger cows cost more to maintain, but their efficiency—and thus profitability— depends on the production environment. Incorporating MWT effectively into selection and mating decisions requires understanding of growth to maturity. The objective of this study was to describe growth to maturity in crossbred beef cattle using Brody, spline, and quadratic functions. Parameter estimates utilized data on crossbred cows from cycle VII and continuous sampling phases of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center. The MWT were estimated at 6 yr from the fitted parameters obtained …
Analysis Of 28 Generations Of Selection For Reproduction, Growth, And Carcass Traits In Swine, W. L. Hsu, Rodger K. Robinson
Analysis Of 28 Generations Of Selection For Reproduction, Growth, And Carcass Traits In Swine, W. L. Hsu, Rodger K. Robinson
Department of Animal Science: Faculty Publications
Selection (28 generations, G) in a Large White–Landrace composite population for traits aimed at increasing live pigs born per litter (BA), with additional selection for increased 180-d weight (WT180) and longissimus muscle area (LMA) and decreased back fat (BF10) in the last 8 generations, was practiced. Objectives herein were to estimate genetic and phenotypic responses and genetic parameters (n = 1,883 to 54,174) and to investigate whether a plateau in response for BA occurred. Line 2 (L2) was selected for an index of ovulation rate and embryo survival (G0 to G11), fully formed pigs (FF) per litter (G12 to 14), …
Bioinformatics Analysis Of Transcriptome Dynamics During Growth In Angus Cattle Longissimus Muscle, Sonia J. Moisa, Daniel W. Shike, Daniel E. Graugnard, Sandra L. Rodriquez-Zas, Robin E. Everts, Harris A. Lewin, Dan B. Faulkner, Larry L. Berger, Juan J. Loor
Bioinformatics Analysis Of Transcriptome Dynamics During Growth In Angus Cattle Longissimus Muscle, Sonia J. Moisa, Daniel W. Shike, Daniel E. Graugnard, Sandra L. Rodriquez-Zas, Robin E. Everts, Harris A. Lewin, Dan B. Faulkner, Larry L. Berger, Juan J. Loor
Department of Animal Science: Faculty Publications
Transcriptome dynamics in the longissimus muscle (LM) of young Angus cattle were evaluated at 0, 60, 120, and 220 days from early-weaning. Bioinformatic analysis was performed using the dynamic impact approach (DIA) by means of Kyoto Encyclopedia of Genes and Genomes (KEGG) and Database for Annotation, Visualization and Integrated Discovery (DAVID) databases. Between 0 to 120 days (growing phase) most of the highly-impacted pathways (eg, ascorbate and aldarate metabolism, drug metabolism, cytochrome P450 and Retinol metabolism) were inhibited. The phase between 120 to 220 days (finishing phase) was characterized by the most striking differences with 3,784 differentially expressed genes (DEGs). …
Effects Of Restricting Energy During The Gilt Developmental Period On Growth And Reproduction Of Lines Differing In Lean Growth Rate: Responses In Feed Intake, Growth, And Age At Puberty, P. S. Miller, R. Moreno, R. K. Johnson
Effects Of Restricting Energy During The Gilt Developmental Period On Growth And Reproduction Of Lines Differing In Lean Growth Rate: Responses In Feed Intake, Growth, And Age At Puberty, P. S. Miller, R. Moreno, R. K. Johnson
Department of Animal Science: Faculty Publications
The overall objective was to compare reproductive performance through 4 parities of gilts developed with ad libitum access to feed or with restriction of energy to 75% of ad libitum intake. Effects on growth and pubertal development are reported. The experiment was a 2 × 2 factorial with 661 gilts. One-half of the gilts (n = 330) were allowed ad libitum access to feed from weaning to breeding at 235 d of age (AL), and 331 littermates were developed with ad libitum access to feed to 123 d of age and then restricted to 75% of ad libitum intake to …
Effect Of Pen Mates On Growth, Backfat Depth, And Longissimus Muscle Area Of Swine, W. L. Hsu, Rodger K. Johnson, L. Dale Van Vleck
Effect Of Pen Mates On Growth, Backfat Depth, And Longissimus Muscle Area Of Swine, W. L. Hsu, Rodger K. Johnson, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Records on final BW (kg), backfat depth (cm), and LM area (cm2) of pigs from a University of Nebraska Large White/Landrace composite population were analyzed to estimate the effects of pen mates. Measurements were at approximately 180 d of age for 3,524 pigs in 351 pens (9 to 11 pigs per pen) farrowed from 1999 to 2005. The area of each pen was 8.13 m2. The full model (M1) included the fixed effects of contemporary group, sex, line, and the covariates of age and inbreeding coefficient, and included random direct genetic, genetic pen-mate, permanent environmental, pen, …
Longitudinal Changes In Ultrasonic Measurements Of Body Composition During Growth In Suffolk Ram Lambs And Evaluation Of Alternative Adjustment Strategies For Ultrasonic Scan Data, J. C. Emenheiser, S. P. Greiner, R. M. Lewis, D. R. Notter
Longitudinal Changes In Ultrasonic Measurements Of Body Composition During Growth In Suffolk Ram Lambs And Evaluation Of Alternative Adjustment Strategies For Ultrasonic Scan Data, J. C. Emenheiser, S. P. Greiner, R. M. Lewis, D. R. Notter
Department of Animal Science: Faculty Publications
Four equations were used to compare alternative procedures to adjust ultrasonic estimates (y) of backfat thickness (BF) and LM area (LMA) for BW using data from a series of 7 scans on 24 Suffolk ram lambs born in 2007. Equations were linear, linear + quadratic, allometric (y = αBWβ), and allometric + BW (ABW; y = αBWβeγW). Goodness of fit was very similar between equations over the range of the data. Resulting adjustment equations were tested using 3 serial scans on winter-born Suffolk (n = 150), Hampshire (n = 36), and Dorset (n = 43) rams and 52 fall-born Dorset …
Bovine Respiratory Disease In Feedlot Cattle: Environmental, Genetic, And Economic Factors, G. D. Snowder, L. Dale Van Vleck, L. V. Cundiff, G. L. Bennett
Bovine Respiratory Disease In Feedlot Cattle: Environmental, Genetic, And Economic Factors, G. D. Snowder, L. Dale Van Vleck, L. V. Cundiff, G. L. Bennett
Department of Animal Science: Faculty Publications
The objective of this study was to characterize genetic, environmental, and economic factors related to the incidence of bovine respiratory disease (BRD) in feedlot calves. Records from 18,112 calves representing 9 breeds (Angus, Braunvieh, Charolais, Gelbvieh, Hereford, Limousin, Pinzgauer, Red Poll, and Simmental) and 3 composite types (MARC I, MARC II, and MARC III) over a 15-yr period (1987 to 2001) were evaluated. Disease incidence was observed and recorded by station veterinary and technical staff. The incidence of BRD varied across years, with the annual observed incidence ranging from 5 to 44%. From 1987 to 1992, the annual average incidence …
Influence Of Breed, Heterozygosity, And Disease Incidence On Estimates Of Variance Components Of Respiratory Disease In Preweaned Beef Calves, G. D. Snowder, L. Dale Van Vleck, L. V. Cundiff, G. L. Bennett
Influence Of Breed, Heterozygosity, And Disease Incidence On Estimates Of Variance Components Of Respiratory Disease In Preweaned Beef Calves, G. D. Snowder, L. Dale Van Vleck, L. V. Cundiff, G. L. Bennett
Department of Animal Science: Faculty Publications
The objective of this study was to characterize genetic and environmental factors influencing bovine respiratory disease (BRD) in beef cattle. Records from nine purebred and three composite breeds and a variety of F1 and three-way crosses, including the progeny of 12 additional different sire breeds produced over a 20-yr period (1983 to 2002), were evaluated for breed and heterozygosity effects on the observed incidence of BRD. Heterozygosity fractions for calves and dams were defined by generalized breed origins: British, Continental, and tropically adapted. Variance components were estimated for each pure and composite breed, and across all breeds and crossbreeds. The …
Genetic And Environmental Factors Associated With Incidence Of Infectious Bovine Keratoconjunctivitis In Preweaned Beef Calves, G. D. Snowder, L. Dale Van Vleck, L. V. Cundiff, G. L. Bennett
Genetic And Environmental Factors Associated With Incidence Of Infectious Bovine Keratoconjunctivitis In Preweaned Beef Calves, G. D. Snowder, L. Dale Van Vleck, L. V. Cundiff, G. L. Bennett
Department of Animal Science: Faculty Publications
Infectious bovine keratoconjunctivitis (IBK) is one of the most economically important diseases in preweaned calves. This study examined the health records of 45,497 calves over a 20-yr period to determine environmental and genetic factors influencing the incidence of IBK. Three data sets were analyzed with an animal model. The first data set (n = 41,986) evaluated environmental factors and genetic differences among nine purebred (Angus, Braunvieh, Charolais, Gelbvieh, Hereford, Limousin, Pinzgauer, Red Poll, and Simmental) and three composite breeds (MARC I, MARC II, and MARC III). Weaning weights of calves diagnosed with IBK were 8.9 kg lighter (P < 0.05) than weights of healthy calves. Incidence of IBK was related to age of the calf and the seasonal life cycle of the face fly (Musca autumnalis …
National Pork Producers Council Maternal Line Genetic Evaluation: A Comparison Of Growth And Carcass Traits In Terminal Progeny, J. P. Cassidy, O. W. Robison, R. K. Johnson, J. W. Mabry, L. L. Christian, M. D. Tokach, R. K. Miller, R. N. Goodwin
National Pork Producers Council Maternal Line Genetic Evaluation: A Comparison Of Growth And Carcass Traits In Terminal Progeny, J. P. Cassidy, O. W. Robison, R. K. Johnson, J. W. Mabry, L. L. Christian, M. D. Tokach, R. K. Miller, R. N. Goodwin
Department of Animal Science: Faculty Publications
The objective of this study was to compare growth and carcass traits of 1,252 progeny of six commercially available dam lines included in the National Pork Producers Council Maternal Line Evaluation Project. Lines compared included one maternal line supplied by each of American Diamond Swine Genetics (ADSG), Danbred NA (DB), two lines supplied by Monsanto Choice Genetics (DK and GPK347), Newsham Hybrids (NH), and Landrace × Large White females supplied by the National Swine Registry (NSR). All females were mated to DB, Duroc-Hampshire terminal sires. Traits analyzed were ADG from 56 to 115 kg live weight, days to 115 kg, …
Responses To 19 Generations Of Litter Size Selection In The Ne Index Line. Ii. Growth And Carcass Responses Estimated In Pure Line And Crossbred Litters, D. B. Petry, J. W. Holl, R. K. Johnson
Responses To 19 Generations Of Litter Size Selection In The Ne Index Line. Ii. Growth And Carcass Responses Estimated In Pure Line And Crossbred Litters, D. B. Petry, J. W. Holl, R. K. Johnson
Department of Animal Science: Faculty Publications
Our objective was to estimate responses in growth and carcass traits in the NE Index line (I) that was selected for 19 generations for increased litter size. Differences between Line I and the randomly selected control line (C) were estimated in pure line litters and in F1 and three-way cross litters produced by mating I and C females with males of unrelated lines. Contrasts of means were used to estimate the genetic difference between I and C and interactions of line differences with mating type. In Exp 1, 694 gilts that were retained for breeding, including 538 I and …
Genetic Relationships Between Sex-Specific Traits In Beef Cattle: Mature Weight, Weight Adjusted For Body Condition Score, Height And Body Condition Score Of Cows, And Carcass Traits Of Their Steer Relatives, K. A. Nephawe, L. V. Cundiff, M. E. Dikeman, J. D. Crouse, L. Dale Van Vleck
Genetic Relationships Between Sex-Specific Traits In Beef Cattle: Mature Weight, Weight Adjusted For Body Condition Score, Height And Body Condition Score Of Cows, And Carcass Traits Of Their Steer Relatives, K. A. Nephawe, L. V. Cundiff, M. E. Dikeman, J. D. Crouse, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Data from the first four cycles of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center (USMARC) were used to investigate genetic relationships between mature weight (MW, n = 37,710), mature weight adjusted for body condition score (AMW, n = 37,676), mature height (HT, n = 37,123), and BCS (n = 37,676) from 4- to 8-yr old cows (n = 1,800) and carcass traits (n = 4,027) measured on their crossbred paternal half-sib steers. Covariance components among traits were estimated using REML. Carcass traits were adjusted for age at slaughter. Estimates of heritability for hot carcass weight (HCWT); …
Growth And Carcass Composition Of Lambs Of Two Breeds And Their Cross Grazing Ryegrass And Clover Swards, J. M. Macfarlane, R. M. Lewis, G. C. Emmans
Growth And Carcass Composition Of Lambs Of Two Breeds And Their Cross Grazing Ryegrass And Clover Swards, J. M. Macfarlane, R. M. Lewis, G. C. Emmans
Department of Animal Science: Faculty Publications
The effects of sward, breed type and sex on lamb growth and carcass composition were measured at two degrees of maturity in live weight. The three breed types were Scottish Blackface (no. =60), Suffolk (no. =59) and their reciprocal crosses (no. =60). The lambs grazed swards of either ryegrass, clover or a mixed sward intended to contain both. The proportion of the mixed sward as clover was only 0·014. Each lamb was scanned using X-ray computed tomography to measure the weights offat, lean and bone in the carcass at two proportions of mature body weight (0·30 and 0·45). Live weights …
Effects Of Food Quality On Growth And Carcass Composition In Lambs Of Two Breeds And Their Cross, R. M. Lewis, J. M. Macfarlane, G. Simm, G. C. Emmans
Effects Of Food Quality On Growth And Carcass Composition In Lambs Of Two Breeds And Their Cross, R. M. Lewis, J. M. Macfarlane, G. Simm, G. C. Emmans
Department of Animal Science: Faculty Publications
The effects offood quality, breed type and sex (ram and ewe) on Iamb growth and carcass composition, and their changes throughout growth, were measured. The three breed typeswereScottish Blackface (B; no. = 24), Suffolk (S; no. = 28) and their reciprocal crosses (X; no. 33). The lambs had free access to a nutritionally non-limiting food, H, or a bulky food, L. Each lamb was scanned using X-ray computed tomography to measure the weights offat, lean and bone in the carcass at three degrees of maturity (0·30, 0·45 and 0·65) in live weight. Live weight and food intake data were recorded …
National Pork Producers Council Maternal Line Genetic Evaluation: A Comparison Of Growth And Carcass Traits In Terminal Progeny, J. D. Cassady, O. W. Berg, Rodger K. Johnson, J. W. Mabry, L. L. Christian, M. D. Tokach, R. K. Miller, R. N. Goodwin
National Pork Producers Council Maternal Line Genetic Evaluation: A Comparison Of Growth And Carcass Traits In Terminal Progeny, J. D. Cassady, O. W. Berg, Rodger K. Johnson, J. W. Mabry, L. L. Christian, M. D. Tokach, R. K. Miller, R. N. Goodwin
Department of Animal Science: Faculty Publications
The objective of this study was to compare growth and carcass traits of 1,252 progeny of six commercially available dam lines included in the National Pork Producers Council Maternal Line Evaluation Project. Lines compared included one maternal line supplied by each of American Diamond Swine Genetics (ADSG), Danbred NA (DB), two lines supplied by Monsanto Choice Genetics (DK and GPK347), Newsham Hybrids (NH), and Landrace × Large White females supplied by the National Swine Registry (NSR). All females were mated to DB, Duroc-Hampshire terminal sires. Traits analyzed were ADG from 56 to 115 kg live weight, days to 115 kg, …
Comparisons Of Angus, Charolais, Galloway, Hereford, Longhorn, Nellore, Piedmontese, Salers, And Shorthorn Breeds For Weight, Weight Adjusted For Condition Score, Height, And Condition Score Of Cows, Jesus Arango, L. V. Cundiff, L. Dale Van Vleck
Comparisons Of Angus, Charolais, Galloway, Hereford, Longhorn, Nellore, Piedmontese, Salers, And Shorthorn Breeds For Weight, Weight Adjusted For Condition Score, Height, And Condition Score Of Cows, Jesus Arango, L. V. Cundiff, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n &#;&#;12,188) of 2- to 6-yr-old cows (n &#; 744) from Cycle IV of the U.S. Meat Animal Research Center’s Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation …
Covariance Functions And Random Regression Models For Cow Weight In Beef Cattle, Jesus Arango, L. V. Cundiff, L. Dale Van Vleck
Covariance Functions And Random Regression Models For Cow Weight In Beef Cattle, Jesus Arango, L. V. Cundiff, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Data from the first four cycles of the Germplasm Evaluation program at the U.S. Meat Animal Research Center were used to evaluate weights of Angus, Hereford, and F1 cows produced by crosses of 22 sire and 2 dam (Angus and Hereford) breeds. Four weights per year were available for cows from 2 through 8 yr of age (AY) with age in months (AM). Weights (n &#;&#;61,798) were analyzed with REML using covariance function-random regression models (CF-RRM), with regression on orthogonal (Legendre) polynomials of AM. Models included fixed regression on AM and effects of cow line, age in years, season of …
Performance Of Mouse Lines Divergently Selected For Heat Loss When Exposed To Different Environmental Temperatures. Ii. Feed Intake, Growth, Fatness, And Body Organs, P. M. Kgwatalala, Merlyn K. Nielsen
Performance Of Mouse Lines Divergently Selected For Heat Loss When Exposed To Different Environmental Temperatures. Ii. Feed Intake, Growth, Fatness, And Body Organs, P. M. Kgwatalala, Merlyn K. Nielsen
Department of Animal Science: Faculty Publications
Mouse populations differing in metabolic rate have been developed through selection for high (MH) and low (ML) heat loss, along with the unselected controls (MC). Objectives of the study were to compare the MH, ML, and MC lines for feed intake, growth, body fatness, and organ weights when reared at 12, 22, and 31°C, and investigate potential line × environment interactions. Feed intake was recorded weekly from 3 to 9 wk of age, and BW at 3, 6, and 9 wk of age. Body fat percent and organ weights were measured at 9 wk of age. No line × environment …
Effects Of Two Dried Forages, And A Choice Between Them, On Intake, Growth And Carcass Composition In Lambs Of Two Breeds And Their Cross, R. M. Lewis, J. M. Macfarlane, G. C. Emmans
Effects Of Two Dried Forages, And A Choice Between Them, On Intake, Growth And Carcass Composition In Lambs Of Two Breeds And Their Cross, R. M. Lewis, J. M. Macfarlane, G. C. Emmans
Department of Animal Science: Faculty Publications
The effects of for age type, breed type and sex on lamb growth and carcass composition, and their changes throughout growth, were measured. The three breed types were Scottish Blackface (no. =31), Suffolk (no. =28) and their reciprocal cross (no. =30). The lambs were given ad libitum a pelleted rye grass alone, pelleted lucerne alone or a choice of both. Each lamb was scanned using X-ray computed tomography to measure the weights of fat, lean and bone in the carcass at three proportions of mature body weight (0-30, 0·45 and 0·65). Live weights and food intake data were recorded weekly. …
Estimates Of Genetic Parameters And Selection Strategies To Improve The Economic Efficiency Of Postweaning Growth In Lambs, G. D. Snowder, L. Dale Van Vleck
Estimates Of Genetic Parameters And Selection Strategies To Improve The Economic Efficiency Of Postweaning Growth In Lambs, G. D. Snowder, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
The objectives of this study were to estimate (co)variance components for growth and feed efficiency measures, and to compare selection strategies to improve economic efficiency of gain. Variance components for pre- and postweaning growth, body weight, and measures of feed efficiency were estimated from data collected on 1,047 Targhee lambs over 7 yr. Approximately 21 d after weaning, lambs were group-fed for 4 wk, with ad libitum access to a diet of 37% whole barley grain and 63% pelleted alfalfa hay. Lambs were then individually fed for 6 wk. Lambs were then returned to group feeding for another 4-wk period. …
Breed Comparisons Of Angus, Charolais, Hereford, Jersey, Limousin, Simmental, And South Devon For Weight, Weight Adjusted For Body Condition Score, Height, And Body Condition Score Of Cows, Jesus Arango, L. V. Cundiff, L. Dale Van Vleck
Breed Comparisons Of Angus, Charolais, Hereford, Jersey, Limousin, Simmental, And South Devon For Weight, Weight Adjusted For Body Condition Score, Height, And Body Condition Score Of Cows, Jesus Arango, L. V. Cundiff, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Breed means and differences for weight (CW, n = 19,851), height (CH, n = 14,553), and condition scores (CS, n = 19,536) recorded in four seasons per year were evaluated for 881 cows ranging from 2 to 7 yr of age from Cycle I of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center. Cows were straightbred Herefords and Angus and top-crosses from mating of Hereford, Angus, South Devon, Jersey, Simmental, Limousin, and Charolais sires to Hereford and Angus dams. The model included cow age, season of measurement, and their interactions, with year of birth, pregnancy-lactation (PL) code, …
Comparisons Of Angus-, Braunvieh-, Chianina-, Hereford-, Gelbvieh-, Maine Anjou-, And Red Poll-Sired Cows For Weight, Weight Adjusted For Body Condition Score, Height, And Body Condition Score, Jesus Arango, L. V. Cundiff, L. Dale Van Vleck
Comparisons Of Angus-, Braunvieh-, Chianina-, Hereford-, Gelbvieh-, Maine Anjou-, And Red Poll-Sired Cows For Weight, Weight Adjusted For Body Condition Score, Height, And Body Condition Score, Jesus Arango, L. V. Cundiff, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Data from Angus, Hereford, and topcross cows (n = 641) from 2- to 8-yr-old daughters of seven breeds of sires included in Cycle II of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center, comprising cow weight (CW, n = 15,698), height (CH, n = 15,676), and condition score (CS, n = 15,667), were used to estimate breed-group differences. Data were recorded in four seasons of each year (1975 to 1982). The mixed model included cow age, season of measurement, and their interactions, year of birth, pregnancy-lactation code (PL), and breed-group as fixed effects for CW and CS. …
Genetic Parameters For Weight, Weight Adjusted For Body Condition Score, Height, And Body Condition Score In Beef Cows, Jesus Arango, Larry V. Cundiff, L. Dale Van Vleck
Genetic Parameters For Weight, Weight Adjusted For Body Condition Score, Height, And Body Condition Score In Beef Cows, Jesus Arango, Larry V. Cundiff, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Weight (CW, n = 61,798), weight adjusted for condition score (WA), hip height (CH, n = 56,494), and condition score (CS, n = 61,434) of cows (2 through 8 yr of age) produced by crosses of 22 sire breeds with Angus and Hereford dams in the first four cycles of the Germplasm Evaluation (GPE) Program at the U.S. Meat Animal Research Center were used to estimate genetic parameters with REML. The model included sire breed, dam breed, age in years, season of measurement (1 to 4) and their interactions, and year of birth and pregnancy-lactation code (PL) as fixed effects …
Breed Comparisons Of Angus, Brahman, Hereford, Pinzgauer, Sahiwal, And Tarentaise For Weight, Weight Adjusted For Condition Score, Height, And Body Condition Score, Jesus Arango, L. V. Cundiff, L. Dale Van Vleck
Breed Comparisons Of Angus, Brahman, Hereford, Pinzgauer, Sahiwal, And Tarentaise For Weight, Weight Adjusted For Condition Score, Height, And Body Condition Score, Jesus Arango, L. V. Cundiff, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Data from topcross cows (n = 468) from six breeds of sire (Angus, Brahman, Hereford, Pinzgauer, Sahiwal, Tarentaise) and two breeds of dam (Angus and Hereford) of Cycle III of the Germplasm Evaluation (GPE) program at the U.S. Meat Animal Research Center (MARC) comprising cow weight (CW, n = 9,012), height (CH, n = 9,010), and condition score (CS, n = 8,991) recorded in four seasons per year from 2 to 6 yr of age were used to estimate breed-group differences. The mixed models included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and …
Effect Of Duration Of Performance Test On Variance Component Estimates For Lamb Growth Rate, G. D. Snowder, L. Dale Van Vleck
Effect Of Duration Of Performance Test On Variance Component Estimates For Lamb Growth Rate, G. D. Snowder, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
The objective was to determine the effect of periods of adjustment and duration of performance test on estimating genetic variance parameters for ADG. Variance components were estimated from ADG data collected from 1978 to 1984 on a total of 1,047 Targhee ewe and ram lambs at the U.S. Sheep Experiment Station (Dubois, ID). Across all years, lambs averaged 84 ± 9 d of age and 25 ± 5.4 kg of weight when placed on test. Lambs were provided ad libitum access to a commercial pellet of barley grain and ground alfalfa for 14 wk. Every 2 wk, ADG was recorded. …
Comparison Of Models For Estimation Of Genetic Parameters For Mature Weight Of Hereford Cattle, J. M. Rumph, R. M. Koch, K. E. Gregory, L. V. Cundiff, L. Dale Van Vleck
Comparison Of Models For Estimation Of Genetic Parameters For Mature Weight Of Hereford Cattle, J. M. Rumph, R. M. Koch, K. E. Gregory, L. V. Cundiff, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Genetic parameters of mature weight are needed for effective selection and genetic evaluation. Data for estimating these parameters were collected from 1963 to 1985 and consisted of 32,018 mature weight records of 4,175 Hereford cows that were in one control and three selection lines that had been selected for weaning weight, for yearling weight, or for an index combining yearling weight and muscle score for 22 yr. Several models and subsets of the data were considered. The mature weight records consisted of a maximum of three seasonal weights taken each year, at brand clipping (February and March), before breeding (May …
A Genetic Evaluation Of Growth In Sheep Using Random Regression Techniques, R. M. Lewis, S. Brotherstone
A Genetic Evaluation Of Growth In Sheep Using Random Regression Techniques, R. M. Lewis, S. Brotherstone
Department of Animal Science: Faculty Publications
Repeated measures of live weight in growing animals are used to describe the path by which they travel from birth to maturity. A family of growth functions-the Gompertz is one in particular-has been used successfully to describe this journey with relatively few parameters (most importantly mature size and a rate parameter). However, using these functions to differentiate the genetic merit of individual animals to grow is problematic since the estimates of these parameters are highly correlated and are obtained with varying precision among animals. An alternative is random regression (RR) methodology. It allows environmental effects specific to the time of …
Usefulness Of Subjective Ovine Milk Scores: I. Associations With Range Ewe Characteristics And Lamb Production, G. D. Snowder, A.D. Knight, L. Dale Van Vleck, C. M. Bromley, T. R. Kellom
Usefulness Of Subjective Ovine Milk Scores: I. Associations With Range Ewe Characteristics And Lamb Production, G. D. Snowder, A.D. Knight, L. Dale Van Vleck, C. M. Bromley, T. R. Kellom
Department of Animal Science: Faculty Publications
Range ewes are commonly evaluated for milking ability by producers to determine the ewe’s ability to rear lamb(s). The U.S. Sheep Experiment Station has subjectively scored (low, average, high) a ewe’s milking ability within 24 h of lambing for many years. The relationship of subjective milk scores with lamb production was investigated using lambing records of Columbia (n = 1,731), Polypay (n = 1,129), Rambouillet (n = 1,704), and Targhee (n = 1,638) ewes. The incidence of high milk scores increased from less than 10% at first parity to 29 to 40% at second and greater parities. At maturity, Columbia …
Usefulness Of Subjective Ovine Milk Scores: Ii. Genetic Parameter Estimates, G. D. Snowder, L. Dale Van Vleck, A. D. Knight, T. R. Kellom, C. M. Bromley
Usefulness Of Subjective Ovine Milk Scores: Ii. Genetic Parameter Estimates, G. D. Snowder, L. Dale Van Vleck, A. D. Knight, T. R. Kellom, C. M. Bromley
Department of Animal Science: Faculty Publications
Genetic parameters for a subjective milk score given to ewes within 24 h of parturition were estimated to determine the usefulness of milk score as a selection trait to improve milk production, which influences total litter weight weaned. Heritability of milk score and the genetic correlation of milk score with litter weight weaned were estimated by REML separately for four sheep breeds, Rambouillet (n = 1,731), Targhee (n = 1,638), Columbia (n = 1,731), and Polypay (n = 1,129). Litter weight weaned was the total weight of lambs weaned at approximately 120 d of age under a western range production …
Genetic Correlations For Litter Weight Weaned With Growth, Prolificacy, And Wool Traits In Columbia, Polypay, Rambouillet, And Targhee Sheep, L. Dale Van Vleck, C. M. Bromley, G. D. Snowder
Genetic Correlations For Litter Weight Weaned With Growth, Prolificacy, And Wool Traits In Columbia, Polypay, Rambouillet, And Targhee Sheep, L. Dale Van Vleck, C. M. Bromley, G. D. Snowder
Department of Animal Science: Faculty Publications
Total litter weight weaned at 120 d postpartum per ewe lambing is often believed to be a measure of range ewe productivity. Genetic correlations for litter weight weaned at 120 d with prolificacy, growth, and wool traits for Columbia, Polypay, Rambouillet, and Targhee sheep were estimated using REML with animal models. Observations per breed ranged from 5,140 to 7,083 for litter weight weaned, from 5,140 to 7,095 for prolificacy traits, from 7,750 to 9,530 for growth traits, and from 4,603 to 18,443 for wool traits. Heritability estimates for litter weight weaned were low and ranged from 0.02 to 0.11. Fraction …