scholarly journals Breeding value evaluation in Polish fur animals: Statistical description of fur coat and reproduction traits – relationship and inbreeding

2011 ◽  
Vol 49 (No. 1) ◽  
pp. 16-27 ◽  
Author(s):  
H. Wierzbicki ◽  
A. Filistowicz ◽  
W. Jagusiak

Three data sets were available: records on conformation and coat traits for the arctic fox from one farm (5 540 observations, collected between 1983 and 1997), and the same traits for the silver fox from three farms (8 199 observations, collected between 1984 and 1999). The third set comprised 5 829 observations on reproductive performance of the arctic fox from one farm, collected between 1984 and 1999. The GLM procedure was used to test the significance of fixed effects on the analysed reproduction traits as well as differences between groups. Phenotypic trends as well as relationship and inbreeding across the studied years were computed. Most of the phenotypic trends were positive. Low relationship and inbreeding coefficients in the arctic and silver fox populations under study were estimated. The average relationship coefficients for the silver and arctic fox populations were 0.015 and 0.010, respectively, whereas the average inbreeding coefficients for the same species were 0.0039 and 0.0016, respectively. No inbreeding was found in the arctic fox breeding females.  

2011 ◽  
Vol 49 (No. 11) ◽  
pp. 474-482 ◽  
Author(s):  
H. Wierzbicki

The study presents estimates of heritability for fur coat and reproduction traits in arctic and silver foxes kept on Polish farms. The estimates of variance components were calculated using the DFREML and single-trait animal models. Due to a discrete character of fur coat traits, they were analysed twice: (1) without normalisation of their scores distribution, (2) after the normal probability scale transformation of their scores. Linear models included random additive genetic and common litter environment effects, and fixed effects of farm × year × birth season in the silver fox or year × birth season in the arctic fox as well as the fixed effect of female age when the reproduction traits were analysed. Moreover, the estimation of variance components for fur coat traits was done by a linear model with (Model 2) or without (Model 1) inbreeding coefficients included as linear covariable. In the arctic fox accounting for inbreeding and the data transformation did not markedly influence the estimates of heritability and the portion of litter variation calculated for the fur coat traits. An inbreeding effect was negligible (except for body size – BS) likely due to the low inbred level of the arctic fox population. In the silver fox the comparison of estimates derived using 2 different linear models and 2 data sets revealed more differences than it was found in the arctic fox. Accounting for inbreeding usually led to lower estimates of heritability, mainly when heritabilities were derived from the normal probability scale-transformed data. Most of the estimates of heritability of reproduction traits were found within the range reported by other authors. However, somewhat higher heritabilities were found for litter size at birth – LSB (0.205) and litter size at weaning – LSW (0.250).    


2011 ◽  
Vol 51 (No. 1) ◽  
pp. 39-46 ◽  
Author(s):  
H. Wierzbicki ◽  
W. Jagusiak

5 540 records of the arctic fox fur coat and reproductive traits collected in 1983–1999 were studied. The analyzed traits were: body size (BS), colour type (CT), colour purity (CP), coat density (CD), hair length (HL), general appearance (GA), total score (TS), skin length (SL), litter size at birth (LSB), litter size at weaning (LSW), number of dead pups (NPD), pup weight at weaning (PW), and pregnancy length (PL). (Co)variance components were estimated using a derivative-free algorithm of REML and a multi-trait animal model. Random effects were direct additive, common litter environment and residual. The genetic parameters for the fur coat traits (discrete characters) were estimated twice: using the original data set, and the data set in which the distribution of fur coat scores was normalised using a probit link function. Direct heritability estimates obtained from the original data set ranged from 0.108 for SL to 0.276 for HL, and were somewhat lower than those estimated using the transformed data set (they ranged from 0.109 for GA to 0.315 for CT). Reproductive traits were lowly heritable with direct heritabilities ranging from 0.060 for PW to 0.174 for LSB. Estimates of the portion of litter variation calculated from the original and transformed data set were comparable ranging from 0.045 for GA to 0.156 for CP, and from 0.059 for GA to 0.185 for TS, respectively. Genetic correlations between fur coat traits ranged from high favourable (0.948 between SL and BS, original data) to strong negative ones between CP and GA (–0.405, transformed data). High positive genetic correlations were found between LSB and LSW (0.954), and between LSB and NPD (0.783), whereas PL was negatively correlated with all other reproductive traits.  


2007 ◽  
Vol 23 (5-6-1) ◽  
pp. 429-436
Author(s):  
D. Radojkovic ◽  
M. Petrovic ◽  
M. Mijatovic ◽  
C. Radovic

The goal of this paper was to investigate the effect of various fixed effects on the number of born alive piglets in litter (NBA), based on results of Swedish Landrace sow fertility on three farms in Serbia, in order to determine the best adapted model for assessing genetic parameters and breeding value. Analysis of phenotipic variability of the NBA of Swedish Landrace sows was carried out based on fertility results on three swine farms (A, B and C) in the Republic of Serbia. Data sets encompassed reproduction indicators for 2803 (A), 1826 (B) and 2235 (C) sows, i.e. their 11014, 6757 and 8452 litters, respectively. For this analysis was used fix model of least square method which includes fixed effects of farrowing number, season of conception shown as combination of year and month, litter genotype, duration of previous period from weaning to conception, effect of sow age at farrowing like quadratic regression nested within farrowing number and linear regression influence of duration of previous lactation. The average NBA was within the interval from 9.13 (A) to 9.76 piglets (B and C). The monitored trait statistically highly significantly (p<0.001) varied under the effect of all systematic factors encompassed by the applied model, regardless of the source of analyzed data, Only the linear regression effect of duration of previous lactation for farm B was assessed as having lower statistical significance (p<0.05).


2021 ◽  
Vol 15 (4) ◽  
pp. 82-90
Author(s):  
A. P. Konovalov ◽  
I. I. Tsepilova ◽  
F. I. Vasilevich

The purpose of the research is evaluating the efficacy of complex therapy using dironet, lactobifadol and keratin food supplement (DLK) against toxascariosis of the arctic fox.Materials and methods. To determine the helminth fauna in the conditions of Vyatka Fur Breeding Farm, 61 females silver fox and 55 females voilevoy arctic fox were used as study objects. To conduct complex therapy against toxascariosis, the study object was 24 females culled from the breeding herd, spontaneously infected with toxascariosis and being clinically healthy. The morphological and biochemical blood parameters in female foxes were determined before and after dehelminthization, and control weighing of animals from experimental groups was carried out before and after the experiment.Results and discussion. Of the studied 116 fur-bearing animals, 26 (22.4%) were infected with Toxascaris leonina. Infection rate of Toxascaris sp. in silver fox females aged 5–7 years was 42.6% when 7-9 eggs were found in one microscope field (magnification 7 × 9). Infection with Toxascaris sp. affects on the body weight of infected animals. The females silver fox from the second experimental group infected with Toxascaris sp., which were not treated, had an average live weight of 1.3 kg less (16.6%) as compared to the control. The complex therapy with the DLK treatment-and-prophylactic complex contributed to the improved metabolic processes and digestion. The applicability of the DLK treatment-and-prophylactic complex for therapy against toxascariosis was proved.


2009 ◽  
Vol 54 (No. 8) ◽  
pp. 349-358 ◽  
Author(s):  
J. Wolf ◽  
J. Smital

Data on 75 567 ejaculates from 1 417 boars of the breeds Czech Large White and Czech Landrace collected in 23 AI centres between 2000 and 2007 were analyzed. Fixed effects were estimated from a four-trait animal model for semen volume, sperm concentration, motility and percentage of abnormal spermatozoa and from single-trait animal models for the total number of spermatozoa and the number of functional spermatozoa. Both the total number of spermatozoa and the number of functional spermatozoa were highest in winter and lowest in summer. Boar’s age had a strong influence on semen volume, the total number and the functional number of spermatozoa; these traits increased especially in the first phase. The percentage of abnormal spermatozoa also increased with age. An interval between successive collections of 7 to 10 days yielded the best values for all semen traits. As semen traits are of direct economic importance for AI centres, it can be expected that the estimation of breeding value for semen traits will become important and that AI centres will choose among top boars for production and female reproduction traits the boars with better semen production.


2011 ◽  
Vol 49 (No. 4) ◽  
pp. 131-136
Author(s):  
D. Vaněk

The purpose of the paper was to analyse the effect of the level of milk yield and breeding value on reproduction of Czech pied cows. In the study of cows that calved in the period 1999&ndash;2001 the results for 41 357&nbsp;cows from the central database were used analytically. The study was focused on the following traits: breeding value of the father of the cow for kg of milk, breeding value of the mother of the cow for kg of milk, the cow&rsquo;s milk yield in the 1st to the 3rd lactation, and reproduction traits after the 1st and 2nd calving. To determine the effect of the breeding value of the father or mother of the cow on reproduction traits of daughters the test cows were divided into 3 groups depending on the BV of the parents. The results were processed by multifactor analysis of variance using the CORR and GLM procedures of the SAS statistical program, v. 8.1., and the model with fixed effects for the calculation itself. The results of the study show a negative correlation between the level of the milk yield of cows and their reproduction. It may be stated that the increased milk yield decreases reproduction traits characterised by the extension of days open and calving interval. The estimated correlation between the milk yield and the days open was r = 0.38 for milk yield, r = 0.32 for fat yield, and r = 0.25 for protein yield. A similar correlation between the level of milk yield and the days open was also found in other calving intervals. &nbsp;


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 10-11
Author(s):  
Jian Cheng ◽  
Rohan Fernando ◽  
Jack C Dekkers

Abstract Efficient strategies have been developed for leave-one-out cross validation (LOOCV) of predicted phenotypes in a simple model with an overall mean and marker effects or animal genetic effects to evaluate the accuracy of genomic predictions. For such a model, the correlation between the predicted and the observed phenotype is identical to the correlation between the observed phenotype and the estimated breeding value (EBV). When the model is more complex, with multiple fixed and random effects, although the correlation between the observed and predicted phenotype can be obtained efficiently by LOOCV, it is not equal to the correlation between the observed phenotype and EBV, which is the statistic of interest. The objective here was to develop and evaluate an efficient LOOCV method for EBV or for predictions of other random effects under a general mixed linear model. The approach is based on treated all effects in the model, with large variances for fixed effects. Naïve LOOCV requires inverting the (n - 1) x (n - 1) dimensional phenotypic covariance matrix for each of the n (= no. observations) training data sets. Our method efficiently obtains these inverses from the inverse of the phenotypic covariance matrix for all n observations. Naïve LOOCV of EBV by pre-correction of fixed effects using the training data (Naïve LOOCV) and the new efficient LOOCV were compared. The new efficient LOOCV for EBV was 962 times faster than Naïve LOOCV. Prediction accuracies from the two strategies were the same (0.20). Funded by USDA-NIFA grant # 2017-67007-26144.


Genetics ◽  
2003 ◽  
Vol 163 (3) ◽  
pp. 1177-1191 ◽  
Author(s):  
Gregory A Wilson ◽  
Bruce Rannala

Abstract A new Bayesian method that uses individual multilocus genotypes to estimate rates of recent immigration (over the last several generations) among populations is presented. The method also estimates the posterior probability distributions of individual immigrant ancestries, population allele frequencies, population inbreeding coefficients, and other parameters of potential interest. The method is implemented in a computer program that relies on Markov chain Monte Carlo techniques to carry out the estimation of posterior probabilities. The program can be used with allozyme, microsatellite, RFLP, SNP, and other kinds of genotype data. We relax several assumptions of early methods for detecting recent immigrants, using genotype data; most significantly, we allow genotype frequencies to deviate from Hardy-Weinberg equilibrium proportions within populations. The program is demonstrated by applying it to two recently published microsatellite data sets for populations of the plant species Centaurea corymbosa and the gray wolf species Canis lupus. A computer simulation study suggests that the program can provide highly accurate estimates of migration rates and individual migrant ancestries, given sufficient genetic differentiation among populations and sufficient numbers of marker loci.


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 8-9
Author(s):  
Zahra Karimi ◽  
Brian Sullivan ◽  
Mohsen Jafarikia

Abstract Previous studies have shown that the accuracy of Genomic Estimated Breeding Value (GEBV) as a predictor of future performance is higher than the traditional Estimated Breeding Value (EBV). The purpose of this study was to estimate the potential advantage of selection on GEBV for litter size (LS) compared to selection on EBV in the Canadian swine dam line breeds. The study included 236 Landrace and 210 Yorkshire gilts born in 2017 which had their first farrowing after 2017. GEBV and EBV for LS were calculated with data that was available at the end of 2017 (GEBV2017 and EBV2017, respectively). De-regressed EBV for LS in July 2019 (dEBV2019) was used as an adjusted phenotype. The average dEBV2019 for the top 40% of sows based on GEBV2017 was compared to the average dEBV2019 for the top 40% of sows based on EBV2017. The standard error of the estimated difference for each breed was estimated by comparing the average dEBV2019 for repeated random samples of two sets of 40% of the gilts. In comparison to the top 40% ranked based on EBV2017, ranking based on GEBV2017 resulted in an extra 0.45 (±0.29) and 0.37 (±0.25) piglets born per litter in Landrace and Yorkshire replacement gilts, respectively. The estimated Type I errors of the GEBV2017 gain over EBV2017 were 6% and 7% in Landrace and Yorkshire, respectively. Considering selection of both replacement boars and replacement gilts using GEBV instead of EBV can translate into increased annual genetic gain of 0.3 extra piglets per litter, which would more than double the rate of gain observed from typical EBV based selection. The permutation test for validation used in this study appears effective with relatively small data sets and could be applied to other traits, other species and other prediction methods.


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