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Full-Text Articles in Life Sciences
Genomic Analysis Of Igg Antibody Response To Common Pathogens In Commercial Sows In Health-Challenged Herds, Leticia P. Sanglard, Piggen Canada, Benny E. Mote, Philip Willson, John C.S. Harding, Graham S. Plastow, Jack C.M. Dekkers, Nick V.L. Serão
Genomic Analysis Of Igg Antibody Response To Common Pathogens In Commercial Sows In Health-Challenged Herds, Leticia P. Sanglard, Piggen Canada, Benny E. Mote, Philip Willson, John C.S. Harding, Graham S. Plastow, Jack C.M. Dekkers, Nick V.L. Serão
Department of Animal Science: Faculty Publications
Losses due to infectious diseases are one of the main factors affecting productivity in the swine industry, motivating the investigation of disease resilience-related traits for genetic selection. However, these traits are not expected to be expressed in the nucleus herds, where selection is performed. One alternative is to use information from the commercial level to identify and select nucleus animals genetically superior for coping with pathogen challenges. In this study, we analyzed the genetic basis of antibody (Ab) response to common infectious pathogens in health-challenged commercial swine herds as potential indicator traits for disease resilience, including Ab response to influenza …
Lamb Wool Shedding Is A Good Predictor Of Ewe Wool Shedding, Napoleón Vargas Jurado, Larry Kuehn, Ronald M. Lewis
Lamb Wool Shedding Is A Good Predictor Of Ewe Wool Shedding, Napoleón Vargas Jurado, Larry Kuehn, Ronald M. Lewis
Department of Animal Science: Faculty Publications
Interest in reducing labour costs due to shearing has led to development of breed types that shed their wool naturally. Selection at young ages can facilitate response. Reliability of predictions of adult from lamb wool shedding (WS) is thus key in the design of breeding programmes to increase shedding. Our objectives were to estimate heritabilities and genetic relationships between WS measured once in lambs and repeatedly in ewes and to assess the accuracy of lamb WS EBV to predict ewe WS EBV based on a multi‐trait threshold or a repeatability model. Data were 4,971 lamb and 3,335 ewe WS records …
The Heritability Of Pampiniform Plexus Vessel Size And Varicocoele In Boars, Tasha R. Gruhot, Lea A. Rempel, Matthew L. Spangler, Stephen D. Kachman, Benny E. Mote
The Heritability Of Pampiniform Plexus Vessel Size And Varicocoele In Boars, Tasha R. Gruhot, Lea A. Rempel, Matthew L. Spangler, Stephen D. Kachman, Benny E. Mote
Department of Animal Science: Faculty Publications
Ultrasonography was used to capture a coronal–sagittal image of the veins of the pampiniform plexus (PP) and the testicular artery of 327 maternal‐line boars at approximately 6 months of age at the University of Nebraska—Lincoln. Varicocoele was diagnosed by two methods. Method 1 diagnosed varicocoele when the average vessel area on one side of the scrotum was 1.5 times larger than the average vessel area on the other side of the scrotum. Method 2 diagnosed varicocoele when the average vessel area on one side of the scrotum of a boar was 1.5 times larger than the average vessel on the …
Effect Of Parentage Misidentification On Estimates Of Genetic Parameters For Milk Yield In The Mediterranean Italian Buffalo Population, Emanuela Parlato, L. Dale Van Vleck
Effect Of Parentage Misidentification On Estimates Of Genetic Parameters For Milk Yield In The Mediterranean Italian Buffalo Population, Emanuela Parlato, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
The objective of this study was to evaluate the effect of parentage misidentification on estimation of genetic parameters for the Italian buffalo population for milk yield from 45,194 lactation records of 23,104 Italian buffalo cows. Animals were grouped into 10 data sets in which sires and dams were DNA identified, or reported from the pedigree, or unknown. A derivativefree restricted maximum likelihood method was used to estimate components of variance with a repeatability model. The model contained age at calving nested within parity and days from calving to conception as linear covariates, herd-year-seasons as fixed effects, and additive genetic, permanent …
A General Review Of Competition Genetic Effects With An Emphasis On Swine Breeding, C. Y. Chen, Rodger K. Morota, S. Newman, L. D. Van Vleck
A General Review Of Competition Genetic Effects With An Emphasis On Swine Breeding, C. Y. Chen, Rodger K. Morota, S. Newman, L. D. Van Vleck
Department of Animal Science: Faculty Publications
A review of previous studies is presented on estimates of genetic parameters and responses to selection with traditional breeding approaches, on correlations between agonistic behavior and growth performance, and on theoretical frameworks for selection incorporating interactions among individuals and on practical methods for incorporating competition effects in breeding programs.
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 …
Estimation Of Genetic Parameters For Growth, Feed Consumption, And Conformation Traits For Double-Muscled Belgian Blue Bulls Performance-Tested In Belgium, N. Gengler, C. Seutin, F. Boonen, L. Dale Van Vleck
Estimation Of Genetic Parameters For Growth, Feed Consumption, And Conformation Traits For Double-Muscled Belgian Blue Bulls Performance-Tested In Belgium, N. Gengler, C. Seutin, F. Boonen, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
For 1,442 Belgian Blue bulls performance- tested at the Centre de Selection de la Race Blanc-Bleue Belge, nine traits were observed: height at withers at 7 mo, height at withers at 13 mo, weight at 7 mo, weight at 13 mo, average feed consumption of concentrates, average daily gain, average feed consumption of concentrates per average daily gain, average feed consumption of concentrates per mean metabolic weight, and price per kilogram of live weight. This price is based on muscle conformation and is therefore used as muscle conformation score. Restricted maximum likelihood with a derivative-free algorithm was used to estimate …
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 Relationship Between Milk Score And Litter Weight For Targhee, Columbia, Rambouillet, And Polypay Sheep, R. M. Sawalha, G. D. Snowder, Jeffrey F. Keown, L. Dale Van Vleck
Genetic Relationship Between Milk Score And Litter Weight For Targhee, Columbia, Rambouillet, And Polypay Sheep, R. M. Sawalha, G. D. Snowder, Jeffrey F. Keown, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
This study was conducted to evaluate the relationship between milk score (MS) and litter weight at 70 d (LW) for four sheep breeds in the United States. Milk score is a subjective measure of milk production used to assess milk production of range ewes when milk yield cannot be quantitatively determined. Variance components for MS and LW were estimated for each of Targhee, Columbia, Rambouillet, and Polypay breeds. Data collected from 1990 through 2000 at the U.S. Sheep Exp. Stn. in Dubois, ID, were analyzed with an animal model using REML. There were 13,900 records of MS and LW for …
Genetic Analysis Of Carcass Traits Of Steers Adjusted To Age, Weight, Or Fat Thickness Slaughter Endpoints, A. Rios-Utrera, L. V. Cundiff, K. E. Gregory, R. M. Koch, M. E. Dikeman, M. Koohmaraie, L. Dale Van Vleck
Genetic Analysis Of Carcass Traits Of Steers Adjusted To Age, Weight, Or Fat Thickness Slaughter Endpoints, A. Rios-Utrera, L. V. Cundiff, K. E. Gregory, R. M. Koch, M. E. Dikeman, M. Koohmaraie, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Carcass measurements from 1,664 steers from the Germ Plasm Utilization project at U.S. Meat Animal Research Center were used to estimate heritabilities (h2) of, and genetic correlations (rg) among, 14 carcass traits adjusted to different endpoints (age, carcass weight, and fat thickness): HCW (kg), dressing percent (DP), adjusted fat thickness (AFT, cm), LM area (LMA, cm2), KPH (%), marbling score (MS), yield grade (YG), predicted percentage of retail product (PRP), retail product weight (RPW, kg), fat weight (FW, kg), bone weight (BNW, kg), actual percentage retail product (RPP), fat percent (FP), and bone percent. …
Genetic Variance And Covariance Patterns For Body Weight And Energy Balance Characters In An Advanced Intercross Population Of Mice, Larry J. Leamy, Kari Elo, Merlyn K. Nielsen, L. Dale Van Vleck, Daniel Pomp
Genetic Variance And Covariance Patterns For Body Weight And Energy Balance Characters In An Advanced Intercross Population Of Mice, Larry J. Leamy, Kari Elo, Merlyn K. Nielsen, L. Dale Van Vleck, Daniel Pomp
Department of Animal Science: Faculty Publications
We estimated heritabilities and genetic correlations for a suite of 15 characters in five functional groups in an advanced intercross population of over 2000 mice derived from a cross of inbred lines selected for high and low heat loss. Heritabilities averaged 0.56 for three body weights, 0.23 for two energy balance characters, 0.48 for three bone characters, 0.35 for four measures of adiposity, and 0.27 for three organ weights, all of which were generally consistent in magnitude with estimates derived in previous studies. Genetic correlations varied from −0.65 to +0.98, and were higher within these functional groups than between groups. …
Lack Of Evidence For Cytoplasmic Effects For Four Traits Of Polypay Sheep, L. Dale Van Vleck, Kathryn J. Hanford, G. D. Snowder
Lack Of Evidence For Cytoplasmic Effects For Four Traits Of Polypay Sheep, L. Dale Van Vleck, Kathryn J. Hanford, G. D. Snowder
Department of Animal Science: Faculty Publications
Analyses of birth and weaning weights, fleece weights of ewes, and number born per litter of Polypay sheep collected at the U.S. Sheep Experimental Station from 1978 through 1998, confirmed previous analyses of three other dual-purpose breeds that cytoplasmic effects do not contribute to variation in these four traits. In general, estimates of genetic parameters that would be needed for national genetic evaluation were similar to previous estimates for Columbia, Rambouillet, and Targhee sheep, although estimates of direct heritability for Polypay were somewhat less for birth weight, slightly greater for weaning weight, significantly greater for fleece weight, and the same …
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 …
Heritability Estimates For Carcass Traits Of Cattle: A Review, Angel Rios Utrera, L. Dale Van Vleck
Heritability Estimates For Carcass Traits Of Cattle: A Review, Angel Rios Utrera, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
We present estimates of heritability for carcass traits of cattle published in the scientific literature. Seventy-two papers published form 1962 to 2004, which reported estimates of heritability for carcass traits, were reviewed. The unweighted means of estimates of heritability for 14 carcass traits by slaughter end point (age, weight, and fat depth) were calculated. Among the three end points, carcass weight, backfat thickness, longissimus muscle area, and marbling score were the carcass traits with the most estimates of heritability (56≤n≤66). The averages for these traits indicate that they are similarly and moderately heritable (0.40, 0.36, 0.40, and 0.37, respectively). However, …
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); …
Genetic Response To Selection For Weaning Weight Or Yearling Weight Or Yearling Weight And Muscle Score In Hereford Cattle: Efficiency Of Gain, Growth, And Carcass Characteristics, R. M. Koch, L. V. Cundiff, K. E. Gregory, L. Dale Van Vleck
Genetic Response To Selection For Weaning Weight Or Yearling Weight Or Yearling Weight And Muscle Score In Hereford Cattle: Efficiency Of Gain, Growth, And Carcass Characteristics, R. M. Koch, L. V. Cundiff, K. E. Gregory, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
An experiment involving crosses among selection and control lines was conducted to partition direct and maternal additive genetic response to 20 yr of selection for 1) weaning weight, 2) yearling weight, and 3) index of yearling weight and muscle score. Selection response was evaluated for efficiency of gain, growth from birth through market weight, and carcass characteristics. Heritability and genetic correlations among traits were estimated using animal model analyses. Over a time-constant interval, selected lines were heavier, gained more weight, consumed more ME, and had more gain/ME than the control. Over a weight-constant interval, selected lines required fewer days, consumed …
Models With Nuclear, Cytoplasmic, And Environmental Effects For Production Traits Of Columbia Sheep, Kathryn J. Hanford, G. D. Snowder, L. Dale Van Vleck
Models With Nuclear, Cytoplasmic, And Environmental Effects For Production Traits Of Columbia Sheep, Kathryn J. Hanford, G. D. Snowder, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Statistical models (16) were compared for birth weight of 24,741 Columbia lambs recorded at the U.S. Sheep Experiment Station (USSES; 1950 to 1998). The goal was to estimate fractions of variance due to cytoplasmic line (c2; n = 590) and sire × cytoplasmic line interaction (sc2; n = 12,831) with other nuclear and environmental effects included in the model. The basic model included direct genetic (fractional variance, a2; n = 26,623), maternal genetic (m2, with direct-maternal correlation ram), and maternal permanent environmental (p2m ; n = 6,385) effects. The model with …
Estimates Of Genetic Parameters And Genetic Change For Reproduction, Weight, And Wool Characteristics Of Targhee Sheep, Kathryn J. Hanford, L. Dale Van Vleck, G. D. Snowder
Estimates Of Genetic Parameters And Genetic Change For Reproduction, Weight, And Wool Characteristics Of Targhee Sheep, Kathryn J. Hanford, L. Dale Van Vleck, G. D. Snowder
Department of Animal Science: Faculty Publications
Genetic parameters from both single-trait and bivariate analyses for prolificacy, weight, and wool traits were estimated using REML with animal models for Targhee sheep from data collected from 1950 to 1998 at the U.S. Sheep Experiment Station, Dubois, ID. Breeding values from both single-trait and seven-trait analyses calculated with the parameters estimated from the single-trait and bivariate analyses were compared across years of birth with respect to genetic trends. The numbers of observations were 38,625 for litter size at birth and litter size at weaning, 33,994 for birth weight, 32,715 for weaning weight, 36,807 for fleece weight and fleece grade, …
Genetic Relationships Between Scrotal Circumference And Female Reproductive Traits, G. Martinez-Valezquez, K. E. Gregory, G. L. Bennett, L. Dale Van Vleck
Genetic Relationships Between Scrotal Circumference And Female Reproductive Traits, G. Martinez-Valezquez, K. E. Gregory, G. L. Bennett, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Records for yearling scrotal circumference (SC; n = 7,580), age at puberty in heifers (AP; n = 5,292), age at first calving (AFC; n = 4,835), and pregnancy, calving, or weaning status following the first breeding season (PR1, CR1, or WR1, respectively; n = 7,003) from 12 Bos taurus breeds collected at the Meat Animal Research Center (USDA) between 1978 and 1991 were used to estimate genetic parameters. Age at puberty (AP) was defined as age in days at first detected ovulatory estrus. Pregnancy (calving or weaning) status was scored as one for females conceiving (calving or weaning) given exposure …
Estimates Of Genetic Parameters And Genetic Change For Reproduction, Weight, And Wool Characteristics Of Columbia Sheep, Kathryn J. Hanford, L. Dale Van Vleck, G. D. Snowder
Estimates Of Genetic Parameters And Genetic Change For Reproduction, Weight, And Wool Characteristics Of Columbia Sheep, Kathryn J. Hanford, L. Dale Van Vleck, G. D. Snowder
Department of Animal Science: Faculty Publications
Genetic parameters from both single-trait and bivariate analyses for prolificacy, weight and wool traits were estimated using REML with animal models for Columbia sheep from data collected from 1950 to 1998 at the U.S. Sheep Experiment Station (USSES), Dubois, ID. Breeding values from both single-trait and seven-trait analyses calculated using the parameters estimated from the single-trait and bivariate analyses were compared with respect to genetic trends. Number of observations were 31,401 for litter size at birth and litter size at weaning, 24,741 for birth weight, 23,903 for weaning weight, 29,572 for fleece weight and fleece grade, and 2,449 for staple …
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 …
Estimates Of Parameters Between Direct And Maternal Genetic Effects For Weaning Weight And Direct Genetic Effects For Carcass Traits In Crossbred Cattle, R. K. Splan, Larry V. Cundiff, M. E. Dikeman, L. Dale Van Vleck
Estimates Of Parameters Between Direct And Maternal Genetic Effects For Weaning Weight And Direct Genetic Effects For Carcass Traits In Crossbred Cattle, R. K. Splan, Larry V. Cundiff, M. E. Dikeman, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Estimates of heritabilities and genetic correlations were obtained for weaning weight records of 23,681 crossbred steers and heifers and carcass records from 4,094 crossbred steers using animal models. Carcass traits included hot carcass weight; retail product percentage; fat percentage; bone percentage; ribeye area; adjusted fat thickness; marbling score, Warner- Bratzler shear force and kidney, pelvic and heart fat percentage. Weaning weight was modeled with fixed effects of age of dam, sex, breed combination, and birth year, with calendar birth day as a covariate and random direct and maternal genetic and maternal permanent environmental effects. The models for carcass traits included …
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 …
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 …
Genetic And Phenotypic Parameters For Dietary Selection Of Mountain Big Sagebrush (Artemisia Tridentata Nutt. Ssp. Vaseyana [Rydb] Beetle) In Rambouillet Sheep, G. D. Snowder, J. W. Walker, K. L. Launchbaugh, L. Dale Van Vleck
Genetic And Phenotypic Parameters For Dietary Selection Of Mountain Big Sagebrush (Artemisia Tridentata Nutt. Ssp. Vaseyana [Rydb] Beetle) In Rambouillet Sheep, G. D. Snowder, J. W. Walker, K. L. Launchbaugh, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
The heritability of diet selection for mountain big sagebrush (Artemisia tridentata Nutt. ssp. vaseyana [Rydb] Beetle) by grazing sheep was estimated from fecal samples collected from 549 Rambouillet ewes. Fecal samples were collected in September and October during 1996 and 1997 from free-grazing ewes on intermountain sagebrush-bunchgrass rangelands at the U.S. Sheep Experiment Station in Idaho. The total number of fecal samples was 1,949. Fecal samples were evaluated for composition of big sagebrush by near-infrared spectroscopy. Percentage of sagebrush in the diet was less in September than in October (21.6 vs 31.7%, respectively). Single-trait and bivariate derivative-free REML analyses …
Parameter Estimates For Greasy Fleece Weight Of Rambouillet Sheep At Different Ages, J. W. Lee, D. F. Waldron, L. Dale Van Vleck
Parameter Estimates For Greasy Fleece Weight Of Rambouillet Sheep At Different Ages, J. W. Lee, D. F. Waldron, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Variance components for greasy fleece weight in Rambouillet sheep were estimated. Greasy fleece weight was modeled either as repeated measurements on the same trait or as different traits at different ages. The original data were separated according to the age of the ewe at shearing into three classes; 1 yr, 2 and 3 yr, and older than 3 yr. An animal model was used to obtain estimates of genetic parameters with a REML algorithm. Total numbers of animals in pedigrees for the different age classes were 696, 729, and 573, respectively, and 822 for the repeated measures model across ages. …
Parameter Estimates For Genetic Effects On Carcass Traits Of Korean Native Cattle, J. W. Lee, S. B. Choi, J. S. Kim, Jeffrey F. Keown, L. Dale Van Vleck
Parameter Estimates For Genetic Effects On Carcass Traits Of Korean Native Cattle, J. W. Lee, S. B. Choi, J. S. Kim, Jeffrey F. Keown, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Data (n = 1,746) collected from 1985 through 1995 on Korean Native Cattle by the National Livestock Research Institute of Korea were used to estimate genetic parameters for marbling score, dressing percentage, and longissimus muscle area, with backfat thickness, slaughter age, or slaughter weight as covariates. Estimates were obtained with REML. Model 1 included animal genetic and residual random effects. Model 2 was extended to include an uncorrelated random effect of the dam. Model 3 was based on Model 1 but also included sire × region × year-season interaction effects. Model 4 combined Models 2 and 3. All models included …
Genetic Parameters Among Weight, Prolificacy, And Wool Traits Of Columbia, Polypay, Rambouillet, And Targhee Sheep, C. M. Bromley, G. D. Snowder, L. Dale Van Vleck
Genetic Parameters Among Weight, Prolificacy, And Wool Traits Of Columbia, Polypay, Rambouillet, And Targhee Sheep, C. M. Bromley, G. D. Snowder, L. Dale Van Vleck
Department of Animal Science: Faculty Publications
Genetic parameters for Columbia, Polypay, Rambouillet, and Targhee sheep were estimated using REML with animal models for prolificacy, weight, and wool traits. All bivariate analyses included a covariance between additive genetic effects for the two traits plus appropriate additional covariances. Number of observations by breed ranged from 5,140 to 7,095 for prolificacy traits, from 7,750 to 9,530 for weight traits, and from 4,603 to 34,746 for wool traits. Heritability estimates ranged from .03 to .11 for prolificacy traits (litter size at birth and litter size at weaning), from .09 to .26 for weight traits (birth weight and average daily gain), …