E.B. Burnside's research while affiliated with University of Guelph and other places

Publications (123)

Article
The objectives of this study were to evaluate antibody (AMIR) and cell-mediated immune responses (CMIR), survival, and somatic cell score (SCS) between purebred Holstein (HO) and crossbred Norwegian Red × Holstein (NRHO) first-calf heifers postpartum. Additionally, immune response traits observed as calves in a previous study were correlated with t...
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Full-text available
Progeny of Holstein females mated to sires of different breeds were genetically evaluated along with their purebred Holstein contemporaries born in the same herds using multiple trait animal models. The resulting estimated breeding values (EBV) of cows were averaged within breed of sire and compared relative to progeny of purebred Holstein sires fo...
Article
As an extension of a former study, the objectives of this study were to evaluate purebred Holstein (HO; n=140) and crossbred Norwegian Red × Holstein (NRFX; n=142) calves for antibody (AMIR) and cell-mediated immune responses (CMIR) as well as survival. Blood was collected on d 0, 14, and 21, and calves were immunized on d 0 and 14 with type 1 (Can...
Article
The objective of this study was to compare the immune response of Holstein and Norwegian Red x Holstein calves on 13 commercial Canadian dairy farms. Data were collected on 135 calves, 68 Holstein and 67 Norwegian Red x Holstein calves aged between 2 and 6 mo. The calves were immunized with hen egg white lysozyme to induce antibody-mediated immune...
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Full-text available
Factor analysis was applied as a multivariate statistical technique to official genetic evaluations of type classification traits for 1,265,785 Holstein cows and 10,321 sires computed from data collected between August 1982 and June 1994 in Canada. Type traits included eighteen linear descriptive traits and eight major score card traits. Principal...
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Methods were developed for the national genetic evaluation of herd life for Canadian Holstein sires. The genetic evaluations incorporate information from survival (direct herd life) and information from conformation traits that are related to herd life (indirect herd life) after adjustment for production in first lactation to remove the effect of c...
Article
A semi-stochastic model for the simulation of genetic improvement in a dairy cattle population was used to evaluate and optimize progeny-testing programs for AI firms that operate in a competitive market for semen from progeny-tested bulls with regard to number of bulls sampled and size of progeny groups. The population was serviced by four firms....
Article
A total of 65,491 lactation means of log2-transformed SCC measures were analyzed from first lactation Holstein cows in Ontario. Effects of inbreeding on SCC were estimated by a nonadditive sire and dam model that included additive, dominance, and additive by additive genetic effects and regression of lactation somatic cell score on inbreeding coeff...
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Hierarchical (each dam mated to one sire) and factorial (each dam mated to several sires) designs involving juvenile selection in a closed nucleus breeding programme were compared for rates of genetic response and inbreeding using stochastic simulation. Numbers of sires and dams selected and herd sizes varied. Generations were discrete. Sires and d...
Article
Additive, dominance, and additive by additive components of genetic variance and inbreeding depression were estimated for production traits from a group of daughters of young sires from the Canadian Holstein population. First lactations of 92,838 cows were analyzed. Three sire and dam models (additive, additive plus dominance, additive plus dominan...
Article
Inbreeding coefficients of >3 million Holstein cows and bulls were computed for the Canadian population. Relative to the population base in 1950, the inbreeding coefficients ranged from 0 to 37.5%. During the period of study, trends for inbreeding increased, except for 1978 through 1986, when inbreeding fell or reached a plateau. More recently, for...
Article
Heritabilities and genetic and phenotypic correlations were estimated for linear scored udder traits, clinical mastitis, incidence of other diseases, and somatic cell count (SCC), using first lactation data from the Danish young sire sampling program. Two sets of data were analyzed using a multi-trait REML procedure with an animal model. Heritabili...
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Stochastic simulation was used to study the effect of selection and mating strategy on rates of genetic response and inbreeding with a closed nucleus breeding program for juvenile and adult schemes with 8 males and 64 females selected to produce 1024 progeny (512 females). Selection strategies considered using all available information or only indi...
Article
Genetic and residual parameters were computed for conformation and performance traits of Limousin bulls in Ontario central test stations. Following editing, data were available on 456 bulls tested in 1990. Genetic parameters for performance traits were similar to those reported in the literature. Heritability of bone score (1-light to 9-heavy) was...
Article
Test day SCC records were obtained from the Ontario DHI and converted to somatic cell score using a logarithmic transformation. Adjustment factors for stage of lactation and calendar month were obtained for first and later lactations. Effects of stage of lactation were significant and followed a systematic pattern. Seasonal effects were small. Sire...
Article
Type classification records of Canadian Holsteins were investigated for evidence of heterogeneous variance across herds. Data consisted of records for 1,139,104 cows from 20,226 herds with classifications on 26 conformation traits collected from 1982 through 1992 and 338,046 cows from 9600 herds with classifications on 2 additional traits from 1990...
Article
Six different variance structures were simulated across herds to fit a real data structure with 197 335 lactations in 924 herds. The homogeneity case, as well as different combinations of heterogeneous variances across herd-year-seasons (HYSs) were considered. A positive correlation of 0.4 was assumed between average production and phenotypic stand...
Article
Six different variance structures were simulated across herds. Data structure corresponded to a sample data set and comprised 197 335 lactations of 82 062 cows distributed in 924 herds. The homogeneity case, as well as different combinations of heterogeneous variances, were considered. Variances were varied assuming a positive correlation of 0.4 wi...
Article
First lactation records from 58,433 Holstein cows were analyzed to investigate the presence of variability of inbreeding depression for production traits among families tracing to different common ancestors. A total of 48 common ancestor families were identified. An animal model that included an interaction between family and inbreeding depression...
Article
Strategies of selection within local populations and of importation of semen and embryos from countries with higher genetic merit are evaluated for genetic improvement of milk yield in Zimbabwe. Local programs are progeny testing in a closed population, progeny testing combined with semen importation to sire 30% of cows, progeny testing with foreig...
Article
An economic evaluation is made on the public investment in breeding strategies for commercial dairy cattle in Zimbabwe, including import of germplasm. Nine strategies are evaluated for their net present value after 25 yr. Benefits are estimated using realistic predictions of the value of the genetic improvement. Cost estimates for the strategies ar...
Article
Milk replacer containing either heated soybean meal (commercial soybean meal), extruded soybean meal, ethanol-extracted soybean meal, fermented soybean meal or skim milk powder replacer (SMPR) was fed for 20 d to preruminant calves from either 6, 18 or 30 d of age (age groups 1, 2 and 3, respectively). Effects of these diets on intestinal absorptio...
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Full-text available
It would be of benefit to the dairy industry to have sires evaluated for the net economic value of their genetic potential for milk-production traits. Economic weights and selection indexes were derived for a variety of production circumstances, taking into account all returns and costs of dairy production and allowing for the existence of quotas....
Article
Animal model estimated breeding values for milk, fat, and protein yields were studied for Italian Friesian cows born from 1972 to 1988. Annual genetic progress for these traits increased from .08 genetic SD/yr prior to 1984 to .25 to .30 genetic SD/yr from 1985 to 1988. The latter trends—double previously reported estimates—were related to selectio...
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Full-text available
Two thousand three hundred and five bulls with complete pedigree information and proofs (ETA) in at least 1 of 10 yr for milk, fat and fat percent were used to study the reliability of genetic evaluations. No evidence was found that bulls with superior genetic evaluations failed to pass on this superiority to their sons and maternal grandsons. The...
Article
A pedigree file of 157,015 male and female Jersey cattle (born after 1955) from the Canadian herdbooks was investigated for the occurrence of inbreeding. A large proportion of Jersey bulls and cows were inbred (32.4 and 36.3% for bulls and cows, respectively). However, average inbreeding coefficients of these inbred cows and of all cows were low. F...
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Full-text available
The genetic variance and heritability of a quantitative trait decrease under directional selection due to the generation of linkage (gametic phase) disequilibrium. After a few cycles of directional selection in a population of infinite sire a steady-state equilibrium is approached. At this point there is no further reduction in these parameters sin...
Article
Full-text available
Summary - The genetic variance and heritability of a quantitative trait decrease under directional selection due to the generation of linkage (gametic phase) disequilibrium. After a few cycles of directional selection in a population of infinite sire a steady-state equilibrium is approached. At this point there is no further reduction in these para...
Article
Bull proofs for milking speed were computed under an animal model for five dairy breeds. Data were subjective scores on first lactation cows from all milk recording agencies across Canada. There were 1411 Holstein, 171 Ayrshire, 85 Jersey, 31 Guernsey, and 17 Brown Swiss bulls that received official evaluations. Bull proofs were expressed on a line...
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Threshold animal models were applied to five conformation traits of Canadian Holsteins. The estimated breeding values for sires from the threshold model allowed the calculation of predicted percentages of daughters in the desirable categories. Results were compared with those from a linear animal model in terms of their ability to predict future pe...
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Sire variances for 30 conformation traits on Canadian Holsteins were estimated on the underlying continuous scale using a single trait threshold linear model. Data were linearized first classifications on 66 617 cows by 3305 sires, classified since February 1988. The model included a random sire effect and fixed effects of herd-round of classificat...
Article
Sixty-five first lactation Holstein heifers, 31 sired by one of 19 top Canadian AI proven sires and 34 sired by one of 19 top New Zealand AI proven sires were compared for production, feed intake, energetic efficiency, body weight and condition. Heifers were fed free choice a high-, medium- and low-energy complete feed for the first 140 d, 141–240...
Article
Standard methods to estimate heritability by half-sib correlation are biased if selection has operated in the parental generation. In this paper a simple method to correct for selection of animals used as sires is described. By selection of both the top and the bottom ranking sires, the sampling variances of the corrected estimates of heritability...
Article
Additive and dominance genetic vari- ances for nine conformation traits in the Canadian Holstein population were esti- mated by REML using the derivative-free algorithm. All traits were analyzed under two sire and dam models differing in assumptions on the data structure. Within-herd relationships due to dam were defined first to be nested within s...
Article
The genetic variance of a quantitative trait decreases under directional selection due to generation of linkage disequilibrium. After a few cycles of selection on individual phenotype, a limit is reached where there is no further reduction in the genetic variance. Bulmer's model is extended to an animal breeding situation where selection is on info...
Article
Thirty-four multiparous and primiparous Holstein cows were utilized to examine the association between the response to long-term administration of recombinant bovine somatotropin and the cow's phenotypic and genetic production potential. Cows representing a range of phenotypic and genetic production potentials were assigned to one of four treatment...
Article
Official 1985 genetic evaluations of Holstein-Friesian dairy sires for milk yield, fat yield and fat percentage from Canada and the U.S.A. were pooled with unofficial 1985 genetic evaluations of sires from Italy in order to obtain international evaluations of sires for these three countries. There were 1766 sires from Canada, 9746 from the U.S.A. a...
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The mean gestation length of an Ontario Holstein population was 281.3 ± 6.0 d. Parity, sex of calf, cow size and size of calf were associated with variation in gestation length. Heritability estimates calculated from sire of the calf and maternal grand-sire of the calf variance components were 0.33 and 0.06, respectively. Genetic correlation betwee...
Article
Breeding receipts from three AI units were merged with Ontario Dairy Herd Improvement Corporation and Record of Performance production records. Data comprised 53,705 heifer, 41,253 lactation 1, 14,688 lactation 2, and 3054 lactation 3 records by daughters of 2150 sires represented in 15,877 herd-year-seasons of birth. Three measures of heifer ferti...
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The phenotypic and genetic correlations between fertility ratings of AI bulls for conception rate and their estimated breeding values for daughters' fertility and production traits were calculated. Genetic correlations between fertility ratings of bulls for conception and heifer fertility traits (age at first breeding, age at last breeding, and num...
Article
Record of Performance and Dairy Herd Improvement Corporation production records of Ontario Holstein cows were merged with breeding receipts of three Ontario AI units from September 1981 through December 1985. Relationships between fertility and production in the first three lactations were investigated for 97,368 daughters of 3806 sires in 22,768 h...
Article
Measurements of double skin fold thickness (mm) were used to assess the feasibility of use of cutaneous delayed-type hypersensitivity response as a marker trait to select for genetically improved disease resistance. Data were from a sample of 149 7-wk-old Holstein calves, from 15 sires, that previously had been sensitized to the contact allergen di...
Article
Microhemagglutination procedures were used to quantify antibody titers against human erythrocytes and ovalbumin in calf sera. Calves were also monitored for the prevalence of pneumonia and diarrhea. Calves, 72 males and 82 females, were the progeny of 15 AI bulls. Blood was sampled weekly for 2 wk after primary and secondary immunizations. Antibody...
Article
Radial immunodiffusion was used to quantify Ig concentrations (mg/100 ml) in the sera of 74 male and 82 female Holstein calves and in whole colostrum from their dams. Calves were the progeny of 15 AI bulls. Blood samples were collected by jugular puncture from calves at birth, 24 to 36 h post first colostrum ingestion, and then weekly from 3 to 7 w...
Article
Genetic parameters for male fertility and fertility ratings of AI bulls were obtained by analyzing 298,013 service records of cows with successive calving records. Cows were mated to 746 service bulls, which were progeny of 126 sires. The model for variance component estimation accounted for fixed effects of herd-year-seasons, sire of the service b...
Article
Use of bovine somatotropin to increase production of milk and milk solids poses the problem of allocation within herd and implications for genetic evaluatation records with and without bovine somatotropin were simulated for different correlations between performance with and without treatment and response to it. Resulting within-herd variances and...
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Full-text available
A joint sire and cow evaluation for selected type traits has been carried out for the Canadian Holstein population using an individual animal model accounting for all known relationships. Only first lactation, first classification linear records were utilized. Linear scores for final class/final score (combined), feet and legs, mammary system, and...
Article
This paper outlines the potential impact of bovine somatotropin on dairy cattle improvement programs and pinpoints research needs. Recording of manufacturer, dosage, and date of start and finish of somatotropin administration is recommended in order to allow analysis of data for cow and sire ranking. Alternatives, such as restriction of somatotropi...
Article
Sire and error variance components and heritabilities were estimated for 26 conformation traits using linear type classifications of 175,693 daughters of 6681 Holstein sires in 21,869 herd-round-classifier subclasses. Estimates from first classifications during first lactations were contrasted with estimates from the same 175,693 females' most rece...
Article
Farmers' subjective evaluations of their cows' milking speed, scored as "very fast", "fast", "average", "slow", or "very slow", were recorded between 1982 and 1985 under Agriculture Canada's Record of Performance milk recording scheme. For the analysis, scores taken at the beginning (score 1) and the end (score 2) of the lactation were distinguishe...
Article
Type information collected by the Holstein Association of Canada from 1976 to 1983 was matched with calving interval records from the Record of Performance program of Agriculture Canada. Type traits considered were final class, major scorecard breakdown traits (general appearance, dairy character, capacity, rump, feet and legs, mammary system, fore...
Article
A model is described for utilizing ancestor estimated transmitting abilities from different countries to increase the accuracy of prediction of the performance of young dairy bulls in artificial insemination within a country. The model was applied to young Canadian Holstein bulls having pedigree information from Canada and the United States. Models...
Article
Sire proofs for stayability to 17, 30, 43, and 55 mo of productive life were related to official production and type proofs in three milk-recording programs: 1) Ontario and Quebec Record of Per- formance, 2) supervised Ontario Dairy Herd Improvement and Quebec Dairy Herd Analysis Service, and 3) owner- sampler Dairy Herd Analysis Service. Simple co...
Article
Farmer-supplied subjective ratings of cows milking speed, scored in 5 categories as 'very fast', 'fast', 'average', 'slow' or 'very slow' were analyzed. Scores were affected by herd- year- season of calving, age at calving and stage of lactation when scored but not by test day milk yield. Heritability estimates were 0.21 and 0.14 for scores up to d...
Article
Type information collected by the Holstein Association of Canada was matched with calving ease data provided by the Ontario Dairy Herd Improvement Corporation. Type traits considered were final class, general appearance, dairy character, capacity, rump, feet and legs, mammary system, fore udder, rear udder, and eight descriptive traits: stature, si...
Article
Radial immunodiffusion techniques were used to determine serum concentrations of immunoglobulins G1, G2, M, and A in 1,293 daughters of 282 Holstein-Friesian sires from 31 herds in southwestern Ontario, Canada. Mean serum immunoglobulin concentrations (mg/100 ml) were 2,163, 2,409, 531, and 107 for immunoglobulins G1, G2, M, and A, respectively. He...
Article
Type classification records for 18 132 Australian Holstein-Friesian heifers were analysed. These consisted of 27 traits scored in three or six categories, from three rounds of classification between 1981 and 1983. Only first lactation, first classification records were considered. The model of analysis included herd-round-classifier subclasses as f...
Article
Thirteen body measurements per cow were collected from 1980 to 1981 on 3,193 Canadian Holstein-Friesian cows by 576 sires in 100 herds. These data were analyzed to test effects of herd, age of cow, stage of lactation, and generation group; to predict sire proofs; to estimate heritabilities and genetic and phenotypic correlations among body measures...
Article
When linear programming is used to rank sires on daughter profits, coefficients of input are required for representative daughters of each sire. Within herd-year-season regressions of daughter's actual 305-day milk, fat percent, days open, 2-min milk yield adjusted for total yield, total milking time, and body weight at birth and first calving on s...
Article
Full-text available
Dairy sires were ranked for overall merit by an average daughter's con- tribution to farm net profit. Biological characteristics of sires and economic factors of a dairy farm were linked by linear programming. Availability and constraints of resources were in the model. Average daughter's returns over variable costs attributable to sire proofs for...
Article
A commercial dairy farm was modelled and linear programming used to maximize gross margins within the farm's limited resources. The model was static, deterministic and over a one-year planning horizon. Cows not required for generating replacements could be mated to either beef or dairy bulls, while calves not used as replacements could be either so...
Article
Single records of 2-min milk yield and total milking time were analyzed including herd-year, age, stage of lactation, and recorded milk yield effects; heritabilities and genetic correlations with production were estimated. Total milking time was measured on 5,083 daughters of 822 sires in 160 herd-years, and 2-rain milk was measured on 9,662 daught...
Article
Milking speed data were obtained for 2604 Holstein-Friesian cows, identified by sire, in test herds located in Quebec and Ontario. Milk samples were collected from each cow and analyzed for somatic cell count. Completed or projected lactation production records were available for this sample of cows. Two-minute yield and total milking time were adj...
Article
Variation, and relation to pneumonia and mastitis, of four immunoglobulins, G1, G2, M, and A of blood serum measured by radial immunodiffusion, was studied in a sample of 190 Canadian Holstein-Friesian females sired by 22 bulls in artificial insemination. Regression analyses indicated that combined effects of age, stage of lactation, parity, and co...
Article
Conception rates of Canadian Holstein-Friesian bulls in artificial insemination were recorded as percent 60- to 90-day nonreturns to first service. A total of 5, 923, 974 first services to 784 bulls by 207 sires were analyzed using a mixed model which included age of bull (1–14 yr), years (1956–1976), months and AI units as fixed effects. Bulls and...
Article
Data were lactations of 82,971 Canadian Holstein-Friesian cows by 4,778 sires recorded from 1975 to 1978 and included final disposal codes. Progeny were required to have first lactation records and were grouped according to whether they had the opportunity to complete one, two, or three lactations. Henderson's Method I technique was used to estimat...
Article
The first sire evaluations for calving ease for bulls used in Ontario were published in May, 1981. Evaluations used calving records collected by Ontario Dairy Herd Improvement Association from all supervised herds from May, 1980, to April, 1981. A total of 34,240 records including herd, breed, sire, and cow identification, date of calving, and info...
Article
Cow estimated transmitting abilities (ETA) for milk yield and fat percent derived by best linear unbiased prediction methods were used to compute averages for each herd and year of calving subclass for herds enrolled on the Record of Production program (ROP). Means and variances of herd averages were tabulated according to province, herd size, and...
Article
Teat conformation characteristics, udder height, total milking yield, 2-min yield, 2-min yield adjusted for the linear and quadratic effects of total milking yield, and 305-day milk and fat yields were recorded on 377 Holstein-Friesian cows in 18 herds. Simple relationships of teat conformation measures and udder height to milk flow rate and produc...
Article
Data collected during two long-term experiments were analyzed by stepwise multiple regression to develop feed intake prediction equations. In one experiment (Sire comparison trial (SCT)) cows were individually fed complete rations ad libitum while in the other (lifetime silage trial (LST)) roughage was fed ad libitum and grain according to producti...
Article
Type classification records of maternal half-sister pairs were analyzed to determine if "Superior" sires differed significantly from "Inferior" sires in their progeny distributions for each type component. "Superior" sires differed by at least one standard deviation in proofs from "Inferior" sires. The sires contrasted were 53 Holstein-Friesian bul...
Article
Milk flow rates determined by a Milk-o-Meter digital totalizer were ob- served on 4,023 Holstein-Friesian cows in Ontario and Quebec to estimate components of variance for sire and error for 2-rain yield and its percentage of total milking yield (2-min %) and to predict differences among sires for milk flow rates. Seven percent of the total variati...
Article
First, second, and third lactation Ontario Record of Performance (ROP) 305-day milk records were analyzed separately to evaluate 246 Holstein sires. Second and third lactation records were analyzed with and without adjustment for realized selection intensity of each bull’s daughters on the basis of first lactation yield. The magnitude of adjustment...
Article
The effect of breed of sire on beef production and carcass characteristics was studied on 222 animals from nine separate trials. Nine breed of sire groups. Ayrshire, British (Angus, Hereford and Shorthorn combined), Burwash, Charolais, Chianina, Jersey, large dairy (Holstein and Brown Swiss combined), Limousin and Maine-Anjou, were represented. The...
Article
Dynamic programming models were developed to optimize culling decisions for Holstein, Jersey, Guernsey, and Ayrshire cows. Parameters of individual breeds for milk yield, milk fat percent, body weight, and disposal reasons were considered. Replacement heifers were allowed to vary in these traits by a probability distribution function. Maxi- mum dis...
Article
A model is described for evaluating dairy sires for the conformation of their daughters accounting for age at classification, year, classification of the dam, genetic trend, and sire effects. Results of the application of this model to two data sets are presented. Estimates of genetic trend for type traits indicated at least twice as much progress...
Article
An experiment was conducted to obtain progeny test comparisons of Finnish and Canadian Ayrshire bulls for veal and beef production. A total of 83 male calves from four Canadian and four Finnish sires was tested. Best linear unbiased estimates of differences between veal calf progeny of Finnish and Canadian bulls for time on test, average daily gain...