scholarly journals Estimation of heritabilities, genetic correlations, phenotypic correlations and genetic trends for production and reproduction traits of Holstein-Friesian dairy cattle using sire model

2013 ◽  
Vol 18 (1) ◽  
pp. 115-128
Author(s):  
Mohamed Osman ◽  
Khairy El-Bayomi ◽  
Sherif Moawed
1986 ◽  
Vol 66 (1) ◽  
pp. 53-65 ◽  
Author(s):  
T. R. BATRA ◽  
A. J. LEE ◽  
A. J. McALLISTER

The relationships between reproduction traits, body weight and milk yield were investigated using data from 1611 heifers and 733 cows from two lines of the National Cooperative Dairy Cattle Breeding Project. The data were analyzed separately for heifers and cows within lines using a mixed linear model containing fixed effects for station, year of birth, season of birth and random effect of sires. Heritability estimates and genetic correlations were estimated by a paternal half-sib analysis. Heritability estimates for heifer and cow reproduction traits ranged between 0 and 26% while those of body weights at calving and 112 d postpartum and milk yield ranged from 24 to 43%. Heifers with difficult calving had a higher incidence of retained placenta than those with normal calving. Phenotypic correlations between heifer reproduction traits and milk yield during first lactation were small. High milk production in cows was associated with longer calving interval. Phenotypic correlations between heifer's and cow's reproduction traits were small. Difficult calving in heifers impairs reproductive performance after calving resulting in greater number of days from calving to first and last breeding and leading to a longer calving interval. Key words: Reproduction traits, heifers, cows, milk yield, dairy cattle


Animals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2271
Author(s):  
Francesco Tiezzi ◽  
Antonio Marco Maisano ◽  
Stefania Chessa ◽  
Mario Luini ◽  
Stefano Biffani

In spite of the impressive advancements observed on both management and genetic factors, udder health still represents one of most demanding objectives to be attained in the dairy cattle industry. Udder morphology and especially teat condition might represent the first physical barrier to pathogens’ access. The objectives of this study were to investigate the genetic component of teat condition and to elucidate its relationship with both milk yield and somatic cell scores in dairy cattle. Moreover, the effect of selection for both milk yield and somatic cell scores on teat condition was also investigated. A multivariate analysis was conducted on 10,776 teat score records and 30,160 production records from 2469 Italian Holstein cows. Three teat scoring traits were defined and included in the analysis. Heritability estimates for the teat score traits were moderate to low, ranging from 0.084 to 0.238. When teat score was based on a four-classes ordinal scoring, its genetic correlation with milk yields and somatic cell score were 0.862 and 0.439, respectively. The scale used to classify teat-end score has an impact on the magnitude of the estimates. Genetic correlations suggest that selection for milk yield could deteriorate teat health, unless more emphasis is given to somatic cell scores. Considering that both at national and international level, the current selection objectives are giving more emphasis to health traits, a further genetic deterioration in teat condition is not expected.


2018 ◽  
Vol 58 (2) ◽  
pp. 207 ◽  
Author(s):  
S. Dominik ◽  
A. A. Swan

The present study estimated phenotypic and genetic relationships between wool production, reproduction and bodyweight traits in Australian fine-wool Merino sheep. The data for the study originated from the CSIRO Fine Wool Project, Armidale, Australia. Data on wool characteristics, measured at ~10 and 22 months of age, bodyweight and several reproduction traits across consecutive lambing opportunities were analysed. The genetic correlations were moderately negative between fibre diameter measured as yearling and adult, and lamb survival (rg = –0.34 ± 0.15 and rg = –0.28 ± 0.14 respectively) and total number of lambs weaned (rg = –0.32 ± 0.21 and rg = –0.40 ± 0.21 respectively). The genetic correlations of yearling and adult greasy and clean fleece weights with number of lambs weaned and fecundity showed moderately to highly negative relationships and a moderately negative correlation with the number of fetuses at pregnancy scanning. Phenotypic correlations between reproduction and wool production traits were estimated to be zero, with the exception of bodyweight showing low to moderate positive phenotypic correlations with total number of lambs born and weaned. Genetic variances were generally low for the reproduction traits and resulted in low heritability estimates (from h2 = 0.03 ± 0.01 to h2 = 0.12 ± 0.13), with the exception of total number of lambs born (h2 = 0.25 ± 0.03). The study indicated that parameter estimation and trait definition of lifetime reproduction records require careful consideration and more work in this area is required.


1995 ◽  
Vol 61 (1) ◽  
pp. 9-18 ◽  
Author(s):  
P. M. Visscher ◽  
M. E. Goddard

AbstractDirect genetic evaluation of profit was investigated as an alternative to a selection index. PROFk was defined as (net income)/(food requirement) until the start of the kth lactation, for k = 2 to 6. Genetic parameters such as heritabilities and genetic correlations were estimated for profit traits for Australian Holstein-Friesian and jersey dairy cattle. Heritabilities for profit until the start of a given lactation were moderate, ranging from 0·12 (for profit until the start of the second lactation in Holsteins) to 0·31 (profit until the start of the third lactation in Jerseys). Genetic correlations between profit traits were very high, and approached unity for most pairs of traits, so that profit early and late in herd life were nearly the same trait. Genetic correlations between profit traits and stayabilities until a given lactation were high, ranging from 0·71 to 0·97. Genetic correlations between profit traits and first lactation milk yield traits were approximately 0·80 for Holsteins and 0·90 for Jerseys. A single analysis urns carried out for lifetime profit using all data, including cows that were still in the herd at the time of data collection. Heritabilities were 0·13 for Holsteins and 0·19 for Jerseys. Genetic correlations between lifetime profit and first lactation yields were high. For the selection of dairy bulls, a multivariate analysis on a milk yield trait (e.g. protein yield) and profit until the last known lactation of bulls' progeny was suggested.


1983 ◽  
Vol 63 (4) ◽  
pp. 781-789 ◽  
Author(s):  
R. K. MOORE ◽  
J. E. MOXLEY ◽  
B. W. KENNEDY ◽  
E. B. BURNSIDE

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 adjusted for the effect of milk yield at sampling and the raw cell counts were transformed to the natural log scale. Sire and error variances were obtained by maximum likelihood (ML) methods and used to estimate heritabilities of and correlations between traits. The heritability estimate for the adjusted 2-min. yield, 0.23, was higher than that for the adjusted total milking time (0.13), with the estimates for the two unadjusted measures being intermediate (0.18). The phenotypic correlations between milking speed and somatic cell count were small. However, there were two distinct linear phases to the relationship between the adjusted 2-min yield and cell count. Small but significant phenotypic correlations were observed between unadjusted measures of milking speed and lactation production (0.11–0.22); however, correlations were not significant when adjustments were made for the milk yield at sampling. Genetic correlations between milking speed and somatic cell count were moderate to large and indicated an antagonistic relationship between faster milking speed and cell count. Also, the genetic correlations suggested some antagonism between increasing 2-min yield and lactation production, while the relationship between lactation traits and milking time was small. Key words: Milking speed, somatic cell count, correlations, heritabilities, Holsteins


2012 ◽  
Vol 28 (4) ◽  
pp. 743-749
Author(s):  
V. Caro-Petrovic ◽  
M.P. Petrovic ◽  
M.M. Petrovic ◽  
Z. Ilic ◽  
N. Maksimovic ◽  
...  

Some phenotypic and genetic trends on growth traits of lambs are observed. The research implicated lambs of two local breeds of sheep: Lipska (LP) and Svrljig (SV). All lambs were weighed for the first time at birth (BWB), and thereafter, regularly in two-week intervals. On the basis of the results during weighing the body weight (BW) were adjusted to the average age: 30 (BW30), 60 (BW60) and 90 days (BW90). Results of the effect of genotype on growth showed a significant effect on the growth traits. Sex of lambs had a significant effect at birth and very significant effect at 30 days, but had no significant effect on weight at 60 (BW60) and 90 (BW90) days. Birth type had significant effect on the body weight from birth to weaning and the highest body weights were recorded in singles. Phenotypic correlations were positive and very highly significant between the growth traits. Genetic correlations were significant, but not between all observed ages of lambs.


1987 ◽  
Vol 44 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Karin Meyer ◽  
Susan Brotherstone ◽  
W. G. Hill ◽  
Maureen R. Edwards

ABSTRACTRecords on 18 939 Friesian-Holstein cows classified for 16 linear-type traits and total score in first lactation by the British Friesian Cattle Society and similarly on 13 192 cows in second lactation were analysed to estimate heritabilities and genetic correlations among the linear traits. These comprised progeny of 542 and 477 young sires, respectively, together with older sires included to increase connections. Correlations of type with milk production traits and correlations between type in first and second lactations were estimated from subsets (of about one-half) of the data. Effects due to proportion of Holstein in the sires were removed.Heritabilities of the linear traits were similar in first and second lactations, ranging from under 0·15 for one of the leg traits to about 0·5 for stature. Genetic correlations between traits in first and second lactation were generally over 0·75, whereas phenotypic correlations for most traits ranged from 0·3 to 0·6. Genetic and phenotypic correlations among the linear traits were generally low, except for those involving size.Phenotypic correlations between linear traits and milk yield and composition were all small, none exceeding 0·3. Genetic correlations were generally almost as small: taking first and second lactations together, the only consistent non-negligible correlations with yield were for angularity (+0·3), fore-udder attachment (–0·2) and udder depth (–0·4). The linear traits are not useful predictors of yield.


1994 ◽  
Vol 59 (2) ◽  
pp. 183-187 ◽  
Author(s):  
S. Brotherstone

AbstractFirst lactation production and linear type records of 72 559Holstein-Friesian cows, calving from 1982 to 1989, were analysed by multivariate restricted maximum likelihood, using a sire model. The data comprised offspring of 1066 randomly used sires, and 91 proven i.e. widely used bulls. All phenotypic correlations between the type traits and the yield traits were small, but moderate genetic correlations were obtained between milk, fat and protein yield and angularity (~—0·43) and between the yield traits and udder depth (~0·44), indicating that higher yielding heifers are more angular and have deeper udders. The heritabilities of the type traits were in line with previous analyses, but those for milk, fat and protein yield were rather high at 0·47, 0·52 and 0·45 respectively


2001 ◽  
Vol 44 (6) ◽  
pp. 589-598
Author(s):  
A. Michaiolowskaja ◽  
N. Mielenz ◽  
L. Schüler ◽  
U. Bergfeld ◽  
U. Müller

Abstract. Title of the paper: Estimation of genetic parameters in the dairy cattle population of Saxonia Population-genetic parameters of the dairy cattle population of Saxonia have been examined. The estimated heritabilities for milk quantity range between 0.35 and 0.42, for fat content between 0.48 and 0.55 and for protein content between 0.52 and 0.57. Higher heritabilities were found for 1st than for subsequent lactations. The genetic correlations between milk quantity and the fat and protein contents were significantly negative for all lactations, likewise between protein content and the protein quantity. The correlation between fat content and fat quantity has been slightly positive (rg=0.08). The analysis of genetic trends revealed a substantial increase in quantity traits, whereas a negative trend has been observed for the milk content merits.


1999 ◽  
Vol 68 (3) ◽  
pp. 413-422 ◽  
Author(s):  
B. J. McGuirk ◽  
I. Going ◽  
A. R. Gilmour

AbstractRecords were analysed on more than 75 000 calvings by 685 Holstein-Friesian bulls tested in commercial dairy herds in England and Wales. The data were collected from 1988 to 1994. The traits analysed were the degree of difficulty at calving, assessed from no difficulty to serious difficulty, calf mortality to 48 h, gestation length and a subjective assessment of calf size. Information was available for the percentage Holstein genes in the sire, dam age (heifer or mature), sex of the calf and the year and month of the calving for all records, while lactation number of the dam and the regional location of the herd were also recorded in 1993 and 1994 (14988 records). Estimates of heritability and genetic and phenotypic correlations were obtained for all traits by restricted maximum likelihood (REML) procedures using a sire model, while also fitting the effects of dam age, calf sex, year and season of calving and significant interations.Heifers had more difficult calvings, higher calf losses and shorter gestations than mature cows while seriously difficult calvings and mortality were higher for male calves (all P < 0·05). Summer months were associated with lower incidences of difficult calvings, lower mortality and shorter gestations. Heritability estimates were 0·05 (s.e. <0·01) for calving difficulty score, 0·45 (s.e. 0·02) for gestation length, 0·02 (s.e. <0·01) for mortality and 0·08 (s.e. <0·01) for calf size score. Heritability estimates for the scored categorical and binomial (mortality) traits were also obtained using threshold model analysis. As expected, these estimates were higher than the REML estimates; 0·12 (s.e. 0.01) for calving difficulty score, 0·08 (s.e. 0·01) for mortality and 0·14 (s.e. 0·01) for calf size score. Calving difficulty score was genetically correlated with calf size score (-0.81), mortality (0.40) and gestation length (0.34) and calf size score was moderately correlated with mortality (-0.40). In all cases, the genetic correlations were stronger than the corresponding phenotypic correlations.Sire genetic merit was predicted for calving difficulty score and the distribution of these predictions is described. Sire predictions for calving difficulty score on the underlying scale were backtransformed to predict the expected incidence of serious difficulties in future calvings.


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