Improving genetic evaluation of litter size and piglet mortality for both genotyped and nongenotyped individuals using a single-step method1

2015 ◽  
Vol 93 (2) ◽  
pp. 503-512 ◽  
Author(s):  
X. Guo ◽  
O. F. Christensen ◽  
T. Ostersen ◽  
Y. Wang ◽  
M. S. Lund ◽  
...  
Keyword(s):  
Litter Size ◽  
Genetic Evaluation ◽  
Single Step ◽  
Piglet Mortality

0303 Issues in commercial application of single-step genomic BLUP for genetic evaluation in American Angus

2016 ◽  
Vol 94 (suppl_5) ◽  
pp. 144-145
Author(s):  
D. A. L. Lourenco ◽  
S. Tsuruta ◽  
B. D. Fragomeni ◽  
Y. Masuda ◽  
I. Pocrnic ◽  
...  
Keyword(s):  
Genetic Evaluation ◽  
Single Step ◽  
Commercial Application

A two-diet system and ad libitum lactation feeding of the sow. 2. Litter size and piglet performance

1996 ◽  
Vol 62 (2) ◽  
pp. 349-354 ◽  
Author(s):  
M. Neil ◽  
B. Ogle
Keyword(s):  
Birth Weight ◽  
Cause Of Death ◽  
Litter Size ◽  
Live Weight ◽  
Feeding Regime ◽  
Conventional Diet ◽  
Feeding Regimes ◽  
Ad Libitum ◽  
Piglet Mortality ◽  
Treatment Mortality

AbstractSixty gilts were allotted to one of the following feeding regimes: CR, a conventional diet offered at a restricted level according to Swedish feeding standards; SA, a simplified gestation diet (mainly oats and barley) offered at a restricted level and a conventional diet offered ad libitum during lactation; CA, a conventional gestation diet offered at a restricted level and the same diet offered ad libitum during lactation. The sows were followed for four parities. Piglet birth weight was unaffected by sow feeding, but differences in piglet live weight were found from 3 weeks of age to the end of the experiment when the piglets were 9 weeks old. CA piglets were heavier than SA piglets at 3 and 9 weeks of age and heavier than both CR and SA piglets at weaning (35 ± 3 days). Litter size was unaffected by treatment as was piglet mortality, whereas the cause of death varied with treatment. Mortality due to trauma was higher among CA piglets than among others, while mortality due to weakness was higher among SA piglets than others and there was also a tendency for higher mortality due to diarrhoea among CR piglets. It was concluded that the CA feeding regime was superior with regards to piglet performance.

A note on the effect of white-flowered peas on sow reproductive performance

1993 ◽  
Vol 56 (1) ◽  
pp. 155-158
Author(s):  
R. B. Ogle ◽  
K. Annér
Keyword(s):  
Litter Size ◽  
Reproductive Performance ◽  
Live Weight ◽  
Soya Bean ◽  
Weight Gains ◽  
Bean Meal ◽  
Piglet Mortality ◽  
Natal Mortality ◽  
Soya Bean Meal ◽  
Size At Birth

The effect on sow reproductive performance of including 100 g white-flowered peas (Pisum sativum hortense, cv. Vreta and Lotta) per kg, replacing barley, wheat and soya-bean meal in gestation and lactation diets, was studied over four parities using 24 pairs of crossbred littermate sows. Net sow weight gains and changes in backfat thickness over the complete reproductive cycle were similar for both treatments. Piglet live-weight gains and mean litter size at birth were not influenced by treatment, although litter size at weaning was 0·5 pigs higher (P > 0·05) for the control sows, due to higher post-natal mortality rate in the litters from the sows given the pea diets. It can be concluded that inclusion of white-flowered peas at a rate of 100 g/kg had no adverse effect on reproductive performance, with the exception of slightly higher post-natal piglet mortality.

Genetic evaluation of crossbred lamb production. 1. Breed and fixed effects for birth and weaning weight of first-cross lambs, gestation length, and reproduction of base ewes

2005 ◽  
Vol 56 (5) ◽  
pp. 443 ◽  
Author(s):  
N. M. Fogarty ◽  
V. M. Ingham ◽  
A. R. Gilmour ◽  
L. J. Cummins ◽  
G. M. Gaunt ◽  
...  
Keyword(s):  
Litter Size ◽  
Fixed Effects ◽  
Mixed Model ◽  
Genetic Evaluation ◽  
Gestation Length ◽  
Production Traits ◽  
Weaning Weight ◽  
Frozen Semen ◽  
Lamb Survival ◽  
Sire Breed

This is the first paper in a series that reports on a national maternal sire central progeny test program (MCPT) to evaluate the genetic variation for economically important production traits in first- and second-cross progeny of maternal and dual purpose (meat and wool) sires and the scope for genetic improvement. The MCPT program also provides direct linkages between breeds that will contribute information for across-breed genetic evaluation. Crossbred progeny by 91 sires from more than 7 maternal breeds (including Border Leicester, East Friesian, Finnsheep, Coopworth, White Suffolk, Corriedale, and Booroola Leicester) at 3 sites over 3 years with 3 link sires in common at each site and year were evaluated in this study. National estimated breeding values for the sires that were entered by industry breeders indicated that there was some selection for weight, but not other traits and the sires were generally representative of the maternal genetics available to the industry. There were 8377 base Merino and Corriedale ewes artificially inseminated with thawed-frozen semen from the 91 sires and 8193 crossbred lambs born and 6117 lambs weaned. Mixed model analyses of birth and weaning weight, lamb survival, and gestation length as well as fertility, litter size, and lamb weaning rate of the base ewes are reported. Sire breed was significant for birth weight (with a range of 4.0–4.4 kg at an average litter size of 1.8) and weaning weight (19.6–22.5 kg), as well as lamb survival (70–79%) and gestation length (147.1–150.3 days). Birth/rearing type was significant for all traits. Males were significantly heavier than females at birth and weaning, although there was no sex difference for lamb survival or gestation length when birthweight was included in the model. Pregnancy rate from the artificially inseminated base ewes varied from 40 to 84% at the 3 locations in the various years. Sire breed was significant for the number of lambs weaned per ewe lambing, but not for fetal number or litter size born. There were also significant differences in performance due to the source of the base ewes at each site.

scholarly journals A cross-specific multiplicative binomial recursive model for the analysis of perinatal mortality in a diallel cross among three varieties of Iberian pig

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Luis Varona ◽  
José Luis Noguera ◽  
Joaquim Casellas ◽  
Melani Martín de Hijas ◽  
Juan Pablo Rosas ◽  
...  
Keyword(s):  
Perinatal Mortality ◽  
Litter Size ◽  
Binomial Distribution ◽  
Genetic Relationships ◽  
Diallel Cross ◽  
Binomial Model ◽  
Average Litter Size ◽  
Or Groups ◽  
Iberian Pig ◽  
Piglet Mortality

AbstractPerinatal piglet mortality is an important factor in pig production from economic and animal welfare perspectives; however, the statistical analysis of mortality is difficult because of its categorical nature. Recent studies have suggested that a binomial model for the survival of each specific piglet with a logit approach is appropriate and that recursive relationships between traits are useful for taking into account non-genetic relationships with other traits. In this study, the recursive binomial model is expanded in two directions: (1) the recursive phenotypic dependence among traits is allowed to vary among groups of individuals or crosses, and (2) the binomial distribution is replaced by the multiplicative binomial distribution to account for over or underdispersion. In this study, five recursive multiplicative binomial models were used to obtain estimates of the Dickerson crossbreeding parameters in a diallel cross among three varieties of Iberian pigs [Entrepelado (EE), Torbiscal (TT), and Retinto (RR)]. Records (10,255) from 2110 sows were distributed as follows: EE (433 records, 100 sows), ER (2336, 527), ET (942, 177), RE (806, 196), RR (870, 175), RT (2450, 488), TE (193, 36), TR (1993, 359), and TT (232, 68). Average litter size [Total Number Born (TNB)] and number of stillborns (SB) were 8.46 ± 2.27 and 0.25 ± 0.72, respectively. The overdispersion was evident with all models. The model with the best fit included a linear recursive relationship between TNB and the logit of $$\phi$$ ϕ of the multiplicative binomial distribution, and it implies that piglet mortality increases with litter size. Estimates of direct effects showed small differences among populations. The analysis of maternal effects indicated that the dams whose mothers were EE had a larger SB, while dams with RR mothers reduced the probability of born dead. The posterior estimates of heterosis suggested a reduction in SB when the sow is crosbred. The multiplicative binomial distribution provides a useful alternative to the binomial distribution when there is overdispersion in the data. Recursive models can be used for modeling non-genetic relationships between traits, even if the phenotypic dependency between traits varies among environments or groups of individuals. Piglet perinatal mortality increased with TNB and is reduced by maternal heterosis.

Litter size at lambing influences genetic evaluation of maternal rearing ability

2018 ◽  
Vol 58 (5) ◽  
pp. 791
Author(s):  
Kim L. Bunter ◽  
Andrew A. Swan ◽  
Daniel J. Brown ◽  
Forbes D. Brien ◽  
Jennifer Smith
Keyword(s):  
Litter Size ◽  
Genetic Correlations ◽  
Genetic Evaluation ◽  
Size Class ◽  
Industry Data ◽  
Common Mean ◽  
Mean And Variance ◽  
Highly Correlated ◽  
Change In Mean

The genetic parameters for maternal rearing-ability of ewes were investigated by ignoring or defining the rearing ability trait separately by litter-size class (singles versus multiples) using multi-generational data from three, fully pedigreed Merino flocks differing in prolificacy, production level and environment. Genetic correlations (ra) between litter size (LSIZE) and the percentage of lambs surviving (PLSURV) were more negative with an increasing mean flock litter size (ra: –0.21 ± 0.17 to –0.73 ± 0.08), while the corresponding range in phenotypic correlations (rp) was substantially lower (rp: –0.15 ± 0.01 to –0.33 ± 0.01). Rearing-ability traits defined separately by litter-size class were highly correlated (ra: 0.49 ± 0.19 to 0.64 ± 0.38), but not genetically identical traits in the most prolific flock. Defining rearing-ability traits separately by litter-size class reduced the antagonistic genetic correlations between LSIZE and PLSURV to between –0.39 ± 0.14 and 0.14 ± 0.28, through accommodating the change in mean and variance of PLSURV with LSIZE. Similarly, linear transformation (TSURV) of PLSURV within each litter size to a common mean and variance reduced the antagonistic trend in genetic correlations between LSIZE and TSURV to range between –0.05 ± 0.17 and –0.43 ± 0.13. Since genetic correlations are low to moderate between TSURV and LSIZE, it is possible to select for improvements in both the number of lambs born and lamb survival simultaneously. Defining rearing-ability traits separately by litter-size class and the role of transformation will be investigated further for improving the accuracy of genetic evaluation for rearing ability across a range of flocks, breeds and environmental conditions using more extensive industry data.

Characteristics of organic pig farms in selected European countries and their possible influence on litter size and piglet mortality

2013 ◽  
Vol 4 (2) ◽  
pp. 163-173 ◽  
Author(s):  
Armelle Prunier ◽  
Sabine Dippel ◽  
Davide Bochicchio ◽  
Sandra Edwards ◽  
Christine Leeb ◽  
...  
Keyword(s):  
Litter Size ◽  
European Countries ◽  
Pig Farms ◽  
Piglet Mortality

Pregnancy scanning can be used as a source of data for genetic evaluation of reproductive traits of ewes

2016 ◽  
Vol 56 (4) ◽  
pp. 679 ◽  
Author(s):  
Kim L. Bunter ◽  
Andrew A. Swan ◽  
Ian W. Purvis ◽  
Daniel Brown
Keyword(s):  
Litter Size ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Reproductive Traits ◽  
Genetic Evaluation ◽  
Fine Tuning ◽  
Data Sources ◽  
Inconsistency Rate ◽  
Scan Data ◽  
Time Frames

Reproductive traits generated from mothering up lambs to ewes (n = 59 603 records) were compared with data resulting from pregnancy scanning (n = 46 663 records), to examine the consistency between the two data sources for deriving specific reproductive traits and to estimate genetic parameters. The reproductive traits considered were fertility (FERT: 0/1) of ewes joined, total litter size (LSIZE: lambs born), the number of lambs surviving at weaning (LSIZEW: lambs weaned) and the percentage of lambs surviving (LSURV = LSIZEW/LSIZE) for ewes that lambed, along with the composite traits number of lambs born (NLB) and number weaned (NLW) for ewes joined. Corresponding trait values were derived from pregnancy scan data (FERT_S, LSIZE_S and NLB_S) for comparison, and were classified as inconsistent if the trait values did not match from scanning and lambing records. Data were obtained from four flocks, representing different time frames, locations, management and breeds or bloodlines. Each flock recorded scan data separately from lambing outcomes. Genetic parameters were estimated separately within each flock. Average levels of inconsistency between scan- and lambing-data values varied between 4.6% and 14.8% across flocks, tending to be highest (9.1–18.5%) for litter size of ewes scanned with multiple fetuses, and lowest (0.29–7.3%) for assignment of fertility. Inconsistencies did not have a significant impact on estimates of trait heritabilities, suggesting recording errors were independent of genetic merit. In three flocks, the genetic correlations (ra) between comparable traits derived from the different data sources were not different from unity (ra ≥ 0.99) even when phenotypic correlations (rp) were lower (rp ≥ 0.84). In the flock with the highest inconsistency rate between data sources, the range in ra varied between 0.60 (fertility) and 1.0 (litter size). Therefore, pregnancy scan data can be directly substituted for reproductive traits traditionally based on lambing data, but attention should be paid to ensuring accuracy of the data sources used. Scan data also provide no information on lamb-survival outcomes after birth, so does not constitute complete data on reproductive outcomes. Genetic evaluation systems might also benefit from fine tuning for scale-induced effects (due to litter size) on parameters to improve the accuracy of across flock prediction of breeding values for reproductive traits.

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