scholarly journals  Effect of service sire on litter size traits in Czech Large White and Landrace pigs

2012 ◽  
Vol 57 (No. 5) ◽  
pp. 220-230 ◽  
Author(s):  
J. Wolf ◽  
M. Wolfová
Keyword(s):  
Litter Size ◽  
Standard Error ◽  
Genetic Parameters ◽  
Random Effect ◽  
Relationship Matrix ◽  
Residual Variance ◽  
Large White ◽  
The Relationship ◽  
Better Than ◽  
Genetic Relationship Matrix

The proportion of variance for service sire effect was estimated for three litter size traits (numbers of piglets born, born alive, and weaned) in Czech Large White (89 231 litters) and Czech Landrace (28 320 litters) pigs. Each trait in the first parity was considered as one trait and that trait in the second and subsequent parities was treated as a repeated trait. Consequently, three two-trait animal models were evaluated for each litter size trait: (i) the service sire effect was included and the complete relationship matrix for all the animals (service sires and sows) was taken into account; (ii) the service sire effect was included as a random effect without inclusion of the relationship matrix; (iii) the service sire effect was omitted from the model. Using the residual variance as a criterion, both models including the service sire effect were slightly better than the model without this effect. Estimates of genetic parameters were very similar for the two models including the service sire effect. The proportion of variance for service sire was in the range from 2 to 3% (standard error approx. 0.2%) in Czech Large White and 2% (standard error approx. 0.3%) in Czech Landrace for all three litter size traits and all models. Models without service sire effect or models including service sire as a simple random effect and without inclusion of the genetic relationship matrix are recommended for genetic evaluation of litter size traits.  

scholarly journals Estimation of variance components, genetic parameters and genetic trends for litter size of swines

2010 ◽  
Vol 39 (10) ◽  
pp. 2155-2159 ◽  
Author(s):  
Leandro Barbosa ◽  
Paulo Sávio Lopes ◽  
Adair José Regazzi ◽  
Robledo de Almeida Torres ◽  
Mário Luiz Santana Júnior ◽  
...  
Keyword(s):  
Litter Size ◽  
Variance Components ◽  
Genetic Parameters ◽  
Random Effect ◽  
Additive Model ◽  
Fixed Effect ◽  
Likelihood Method ◽  
Phenotypic Variance ◽  
Estimation Of Variance ◽  
Genetic Trends

Records of Large White breed animals were used to estimate variance components, genetic parameters and trends for the character total number of born piglets (TNBP) as measure of litter size. For obtaining variance components and genetic parameters, it was used the Restricted Maximum Likelihood Method using MTDFREML software. Two mixed models (additive and repeatability) were evaluated. The additive model contained fixed effect of the contemporary group and the following random effects: direct additive genetic and residual effect for the first parturition. Repeatability model had the same effects of the additive model plus parturition order fixed effect and non-correlated animal permanent environment random effect for the second, third and forth parturition. Direct additive heritability estimates for TNBP were 0.15 and 0.20 for the additive and repeatability models, respectively. The estimate of the ration among variance of the non-correlated effect of animal permanent environment effect and the phenotypic variance, expressed as total variance proportion (c2) was 0.09. The estimates of yearly genetic trends obtained in the additive and repeatability models have similar behaviors (0.02 piglets/sow/year).

The relationship between age at first effective service and numbers born in the gilt litter in purebred pigs

1987 ◽  
Vol 1987 ◽  
pp. 101-101
Author(s):  
J.T. Mercer
Keyword(s):  
Standard Deviation ◽  
Litter Size ◽  
Management System ◽  
Ovulation Rate ◽  
Reproductive Parameters ◽  
Large White ◽  
The Relationship ◽  
Effective Service

Practical use is made of an increase in the ovulation rate of gilts over the first few oestrous cycles. In large herds it may well be easier to increase the interval between entry into the herd and first service in order to improve the size of the first litter. The present study considers existing herd records, taken from the Easicare management system, in which the relationship between age at first litter and reproductive parameters in the first parity are examined. A total of 3778 gilt litters were involved, mostly Large White or Landrace, from 14 nucleus or multiplication herds. Average age at first litter ranged from 342 to 376 days across herds and total numbers born per litter from 9.03 to 11.27. Within herd variation in age at first service ranged from a standard deviation of 19 days to 40 days, that of litter size being more consistent, ranging from 2.45 to 3.21. The within herd regressions between these traits were generally small, averaging 0.007 piglets per day, and insignificant (p>0.05).

Studies in sow reproduction. 2. The effect of lactation length on the subsequent reproductive performance of the sow

1975 ◽  
Vol 20 (3) ◽  
pp. 401-406 ◽  
Author(s):  
D. J. A. Cole ◽  
M. A. Varley ◽  
P. E. Hughes
Keyword(s):  
Litter Size ◽  
Reproductive Performance ◽  
Curvilinear Relationship ◽  
Large White ◽  
Lactation Length ◽  
Average Litter Size ◽  
The Relationship ◽  
Sow Reproduction

SUMMARYForty litters were weaned from their Landrace × Landrace × Large White dams at 2-day intervals to give a range of lactation lengths from 4 to 42 days. A significant (P<0·001) negative curvilinear relationship was observed between lactation length and the interval from weaning to first oestrus. This period was increased by 4·2 days with the reduction of lactation from 42 to 4 days. The relationship between lactation length and the interval from farrowing to remating was significant (P<0·001) and positively linear over the whole range of observations. A decrease of 1 day in lactation length reduced this interval by 0·91 days. Very short lactations were associated with reduced litter size at the following farrowing; sows weaned after lactation lengths between 4 and 21 days had an average litter size of 9–6 piglets born per litter in the next parity, whereas sows weaned following lactation lengths between 21 and 42 days had an average of 12·7 piglets born in the next parity (P<0·01).

scholarly journals Identifying early indicator traits for sow longevity using a linear-threshold model in Thai Large White and Landrace females

2021 ◽  
Vol 34 (1) ◽  
pp. 20-25
Author(s):  
Suppasit Plaengkaeo ◽  
Monchai Duangjinda ◽  
Kenneth J. Stalder
Keyword(s):  
Litter Size ◽  
Genetic Parameters ◽  
Threshold Model ◽  
Genetic Associations ◽  
Genetic Trait ◽  
Large White ◽  
Linear Threshold ◽  
Sow Longevity ◽  
Linear Threshold Model ◽  
Indicator Traits

Objective: The objective of the study was to investigate the possibility of utilizing an early litter size trait as an indirect selection trait for longevity and to estimate genetic parameters between sow stayability and litter size at different parities using a linear-threshold model for longevity in Thai Large White (LW) and Landrace (LR) populations.Methods: The data included litter size at first, second, and third parities (NBA1, NBA2, and NBA3) and sow stayability from first to fourth farrowings (STAY14). The data was obtained from 10,794 LR and 9,475 LW sows. Genetic parameters were estimated using the multipletrait animal model. A linear-threshold model was used in which NBA1, NBA2, and NBA3 were continuous traits, while STAY14 was considered a binary trait.Results: Heritabilities for litter size were low and ranged from 0.01 to 0.06 for both LR and LW breeds. Similarly, heritabilities for stayability were low for both breeds. Genetic associations between litter size and stayability ranged from 0.43 to 0.65 for LR populations and 0.12 to 0.55 for LW populations. The genetic correlation between NBA1 and STAY14 was moderate and in a favorable direction for both LR and LW breeds (0.65 and 0.55, respectively).Conclusion: A linear-threshold model could be utilized to analyze litter size and sow stayability traits. Furthermore, selection for litter size at first parity, which was the genetic trait correlated with longevity, is possible when one attempts to improve lifetime productivity in Thai swine populations.

scholarly journals Bayesian inference of genetic parameters on litter size and gestation length in Hungarian Landrace and Hungarian Large White pigs

2009 ◽  
Vol 8 (sup3) ◽  
pp. 68-70
Author(s):  
Istvàn Nagy ◽  
Ino Curik ◽  
Jànos Farkas ◽  
Làszló Csatór ◽  
Zoltàn Csörnyei
Keyword(s):  
Bayesian Inference ◽  
Litter Size ◽  
Genetic Parameters ◽  
Gestation Length ◽  
Large White

scholarly journals Simultaneous estimation of genetic parameters for production and litter size traits in Czech Large White and Czech Landrace pigs

2013 ◽  
Vol 58 (No. 9) ◽  
pp. 429-436 ◽  
Author(s):  
E. Krupa ◽  
J. Wolf
Keyword(s):  
Litter Size ◽  
Genetic Parameters ◽  
Genetic Evaluation ◽  
Simultaneous Estimation ◽  
Large White ◽  
Lean Meat ◽  
Absolute Value ◽  
Meat Content ◽  
Reproduction Traits ◽  
Daily Gain

Genetic parameters for total number of piglets born per litter, number of piglets weaned per litter, lean meat content, and average daily gain from birth till the end of the field test were estimated for Czech Large White (445 589 records) and Czech Landrace (149 057 records) pigs using a four-trait animal model. The following heritabilities were estimated (first number: Large White, second number: Landrace): 0.10 &plusmn; 0.004 and 0.09 &plusmn; 0.007 for total number born; 0.09 &plusmn; 0.005 and 0.07 &plusmn; 0.008 for number weaned; 0.39 &plusmn; 0.004 and 0.36 &plusmn; 0.009 for lean meat content; 0.21 &plusmn; 0.004 and 0.18 &plusmn; 0.006 for daily gain. The highest genetic correlation (approximately 0.85 in both breeds) was estimated between both litter size traits. In Czech Landrace, all remaining genetic correlations were &lt; 0.20 in their absolute value. Negative correlations of approximately ‑0.25 were estimated in Czech Large White between daily gain and both reproduction traits. All remaining correlations in Czech Large White were also &lt; 0.20 in their absolute value. The estimated non-zero correlations between production and reproduction traits are, besides of other arguments, one reason to recommend a joint genetic evaluation of production and reproduction traits. If more than one litter trait is included in the genetic evaluation, repeatability models should be used instead of separate treating the first and the second and subsequent litters; this is because of the high correlations among litter size traits which are expected to cause numerical problems if multi-parity models are used. &nbsp;

scholarly journals Genetic Parameters for Age at First Calving and First Calving Interval of Beef Cattle

Animals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2122
Author(s):  
Michaela Brzáková ◽  
Jindřich Čítek ◽  
Alena Svitáková ◽  
Zdeňka Veselá ◽  
Luboš Vostrý
Keyword(s):  
Beef Cattle ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Performance Testing ◽  
Breeding Strategy ◽  
Relationship Matrix ◽  
Calving Interval ◽  
Data Set ◽  
Age At First Calving ◽  
The Relationship

The objective of this study was to estimate genetic parameters for age at first calving (AFC) and first calving interval (FCI) for the entire beef cattle population and separately for the Charolais (CH) and Aberdeen Angus (AA) breeds in the Czech Republic. The database of performance testing between the years 1991 and 2019 was used. The total number of cows was 83,788 from 11 breeds. After editing, the data set contained 33,533 cows, including 9321 and 4419 CH and AA cows, respectively. The relationship matrix included 85,842 animals for the entire beef population and 24,248 and 11,406 animals for the CH and AA breeds, respectively. A multibreed multitrait animal model was applied. The estimated heritability was low to moderate. Genetic correlations between AFC and FCI varied depending on the breeds from positive to negative. Differences between variance components suggest that differences between breeds should be considered before selection and breeding strategy should be developed within a breed.

Relationships between ovulation rate, prenatal survival and litter size in French Large White pigs

1996 ◽  
Vol 63 (1) ◽  
pp. 143-148 ◽  
Author(s):  
A. Blasco ◽  
J. Gogué ◽  
J. P. Bidanel
Keyword(s):  
Litter Size ◽  
Individual Variation ◽  
Negative Relationship ◽  
Ovulation Rate ◽  
White Population ◽  
Large White ◽  
High Positive Correlation ◽  
The Individual ◽  
The Right ◽  
The Relationship

AbstractThe relationship between total number born (TNB), ovulation rate (CL) and prenatal survival was analysed in a French Large White population. The left ovary had a significantly (P < 0·01) higher ovulation rate (7·9) than the right ovary (6·9). Prenatal survival showed an ovum wastage of 35 or 37% depending on whether referred to total number born or number born alive. No differences between parities were found in these traits. There was a negative relationship between ovulation rate at both sides (v = −0·34). There was a negative relationship between CL and prenatal survival (r = −0·37), a low correlation between CL and TNB (i = 0·19), and a high positive correlation between prenatal survival and TNB (i = 0·82). Litter size showed a quadratic relationship with ovulation rate, and the individual variation for each class of ovulation rate was found to be high. The relationship between prenatal survival and ovulation rate was found to be linear, and a high individual variation for each class of litter size was also found. The relationships between prenatal survival and litter size were quadratic, but depended much less on individual variation.

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