The genetic foundation of fitness and reproduction traits in Australian pig populations. 2. Relationships between weaning to conception interval, farrowing interval, stayability, and other common reproduction and production traits.

1996 ◽  
Vol 47 (8) ◽  
pp. 1275 ◽  
Author(s):  
E Tholen ◽  
KL Bunter ◽  
S Hermesch ◽  
HU Graser

Data sets from 2 large Australian piggeries were used to estimate genetic parameters for the traits weaning to conception interval (WCIi-l,i) and farrowing interval (FIi-l,i), number born alive (NBAI), average piglet birthweight (BWi), 21-day litter weight (W21i), and sow stayability (STAYli) recorded for each ith parity, as well as sow average daily gain (ADG) and backfat (BF) recorded at the end of performance test. Over parities and herds, heritabilities for each trait were in the ranges: WCI/FI, 0.0-0.10; NBA, 0.09-0.16; BW, 0.11-0.35; W21, 0.12-0.23; STAYli, 0.02-0.09; ADG, 0.35-0.37; BF, 0.36-0.45. Genetic correlations between NBAl and NBA from later parities were significantly different from 1. In addition, in 1 herd negative genetic correlations (rg = -0.04 to -0.25) were found between sow stayability traits and NBA1, but not NBA recorded in later parities. Stayability was Unfavourably correlated with ADG and BF, and favourably correlated with WCI12. However, WCI12 was unfavourably correlated genetically with BF (rg = -0.24) but uncorrelated with ADG. Antagonistic relationships also existed between NBA and BW, NBA and W21, and BW and STAY. In addition to the traditional traits currently included in pig-breeding programs (e.g. ADG, BF, and NBA), traits such as WCI, BW, and STAY should also be considered as selection criteria to minimise the detrimental effects of antagonistic genetic relationships between traits.

2011 ◽  
Vol 50 (No. 3) ◽  
pp. 96-103 ◽  
Author(s):  
J. Wolf ◽  
E. Žáková ◽  
E. Groeneveld

The covariance structure was estimated by REML for a joint genetic evaluation of production and reproduction traits for Czech Landrace (58 258 records) and Czech Large White (167 161 records) pigs using four-trait animal models. The following traits were analysed: lean mean percentage at the end of the performance test in the field, estimated from ultrasonic measurements unadjusted for live weight (LM), average daily gain in field test (in g/day) calculated as weight at the end of the test divided by age at the end of the test (ADG), number of piglets born alive in parity 1 (NBA1) and number of piglets born alive in parity 2 and subsequent parities (NBA2+). The heritabilities were in the range from 0.30 to 0.37 for LM, from 0.13 to 0.18 for ADG, from 0.09 to 0.13 for NBA1 and from 0.10 to 0.14 for NBA2+, depending on the breed and on the model (herd-year-season random or fixed). Genetic correlations between production and reproduction traits were estimated to be non-zero. Correlations between traits caused by the herd-year-season effect were mostly positive. As a general conclusion, the joint genetic evaluation of production and reproduction traits is recommended. The herd-year-season effect should be preferably considered as random.  


2000 ◽  
Vol 43 (5) ◽  
pp. 451-462
Author(s):  
S. Karsten ◽  
R. Röhe ◽  
V. Schulze ◽  
H. Looft ◽  
E. Kalm

Abstract. Title of the paper. Genetic association between individual feed intake during Performance test and reproductions traits in pigs The present study deals with the estimation of genetic correlations between Performance test traits measured in boars and reproduction traits of their offspring (sibs) of two purebred lines. Performance traits were individual feed intake (FI) recorded by electronic feeder, feed conversion ratio (FCR), average daily gain (ADG) and backfat thickness (BF). Reproduction traits were number of total piglets born (NBT) and born alive (NBA) Data of 4869 young boars, Performance tested between April 1992 and May 1997 and data of 9710 primiparous sows farrowed between June 1994 to November 1998, were observed. Heritabilities of Performance traits recorded on Station were in line 03 (line 04) h2 = 0.24 (0.33), 0.33 (0.33), 0.23 (0.32) and 0.47 (0.53) for FI, ADG FCR and BF, respectively. Heritabilities of reproduction traits such as NBT, NBA were in line 03 (line 04) h2 = 0 05 (0.08) and 0.05 (0.06), respectively. Genetic correlation between individual feed intake and reproduction traits ranged between rg = 0.12 and 0.27. Undesirable genetic correlations were found between reproduction traits and feed efficiency (rg = 0.13 to 0.44), backfat thickness (rg = 0.07 to 0.25) and partly average daily gain (rg = −010 to 0.09). Line 04 showed lowest magnitude of feed intake and highest genetic antagonism between production and reproduction traits. It is suggested that feed intake capacity is a limiting factor for reproduction in line 04 and genetic antagonism between production and reproduction traits increases with reduction in feed intake.


1982 ◽  
Vol 62 (3) ◽  
pp. 665-670 ◽  
Author(s):  
D. C. JEFFRIES ◽  
R. G. PETERSON

Genetic parameters were estimated for 2403 purebred Yorkshire pigs over a 2-yr period, representing 21 sires. The traits studied included average daily gain, age adjusted to 90 kg, ultrasonic measurements of backfat at the mid-back and loin positions, total and adjusted total ultrasonic backfat and corresponding carcass backfat measurements. Least squares analyses were used to estimate and adjust for the effects of sex, year-season and sex by year-season interaction. Heritabilities and genetic correlations were calculated for all traits using both half- and full-sib estimates. Adjusted age and adjusted total ultrasonic backfat measurements were found to have the highest heritabilities of the live traits in this study. Estimates of heritability for adjusted age and adjusted total ultrasonic backfat were 0.24 ± 0.10 and 0.26 ± 0.10 based on half-sib and 0.56 ± 0.07 and 0.41 ± 0.06 from full-sib analyses. The genetic correlation between these two traits was −0.07 ± 0.28 based on the half-sib method. The total phenotypic correlation was −0.01 ± 0.02. Key words: Swine, ultrasonic backfat, heritabilities, genetic correlations


2000 ◽  
Vol 43 (3) ◽  
pp. 287-298
Author(s):  
J. Bizelis ◽  
A. Kominakis ◽  
E. Rogdakis ◽  
F. Georgadopoulou

Abstract. Production and reproduetive traits in Danish Landrace (LD) and Large White (LW) swine were analysed by restricted maximum likelihood methods to obtain heritabilities as well as genetic and phenotypic correlations. Production traits were: age, backfat thickness (BT), muscle depth (MD) and the ratio BT/MD, adjusted to Standard bodyweight of 85 kg. Reproduction traits were: number of pigs born (NB) and number of pigs weaned (NW) per sow and parity. Heritabilities for age, BT, MD and BT/MD were 0.60, 0.44, 0.51 and 0.42 for LD and 0.36, 0.44, 0.37 and 0.45 for LW, respectively. Genetic correlations between age and BT were −0.22 in LD and – 0.44 in LW. The genetic correlation between age and MD was close to zero in both breeds. Genetic correlation between BT and MD were −0.36 and −0.25 in LD and LW, respectively. Heritabilities for NB were 0.25 in LD and 0.13 in LW while heritabilities for NW were close to zero in both breeds. Genetic correlation between NB and NW was 0.46 and 0.70 in LD and LW, respectively.


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.


1997 ◽  
Vol 65 (2) ◽  
pp. 275-283 ◽  
Author(s):  
R. E. Crump ◽  
C. S. Haley ◽  
R. Thompson ◽  
J. Mercer

AbstractEstimates of heritabilities, common litter of birth effects and additive maternal genetic effects were produced for ultrasonic backfat depth, average daily food intake, average daily gain and food conversion ratio of Landrace boars and gilts. Boars and gilts were performance tested under different regimes. A bivariate derivative-free restricted maximum likelihood procedure was used to estimate genetic correlations between the performance test traits as recorded in the two sexes.Heritability estimates from the analysis including the common litter of birth effect tended to be towards the low end of the range of recently published estimates. This may reflect either population specific effects, such as effects of long-term selection, or the use of an individual animal model.Estimates of the common litter of birth effect were around 0·05, and generally had a significant effect upon the fit of the model, while additive maternal genetic effect estimates were negligible. Therefore, it is expected that omission of maternal effects from models for evaluation by best linear unbiased prediction will not hinder genetic progress. Inclusion of common litter of birth effects would be recommended, although this result may not hold for populations given food ad libitum.The estimates of genetic correlations between performance test traits of boars and gilts indicate that the levels of genotype-environment interaction (G × E) and genotype-sex interaction were low across most traits and data sets, with all genetic correlation estimates lying between 0·8 and 1·0. The lowest estimates of the genetic correlations, which were observed in data sets where the environments appeared to differ most, indicate that G × E interactions may be a problem in populations where males and females are subject to test regimes with greater differences than those seen here.


2013 ◽  
Vol 56 (1) ◽  
pp. 191-199 ◽  
Author(s):  
I. Nagy ◽  
P. Gyovai ◽  
I. Radnai ◽  
H. Nagyné Kiszlinger ◽  
J. Farkas ◽  
...  

Abstract. Genetic parameters, inbreeding depression and genetic trends were estimated for average daily gain between the ages of 5-10 weeks and thigh muscle volume (measured in vivo with computerized tomography) in a group of 22 098 Pannon terminal line rabbits born between 2006 and 2011 and reared in 3 396 litters. The data sets were analysed with bi-variate animal models taking pedigree completeness (complete generation equivalent) into account. By 2011, all rabbits were inbred and the average inbreeding coefficient and complete generation equivalent of the population were 7.69 % and 11.89 %, respectively. Estimated heritability was moderate both for average daily gain (0.23±0.02) and thigh muscle volume (0.25±0.03). Litter effects were low for both traits (0.16±0.00 and 0.09±0.01 respectively). The genetic correlation coefficient estimate between average daily gain and thigh muscle volume was also low (0.02±0.08). Significant inbreeding depression (per 10 % inbreeding) was only detected for average daily gain (0.57 g/d). The estimated annual selection response was substantial both for average daily gain and thigh muscle volume (1.49 g/d and 5.84 cm3, respectively), proving the efficiency of the breeding programme.


2012 ◽  
Vol 55 (6) ◽  
pp. 603-611 ◽  
Author(s):  
F. Ghafouri-Kesbi ◽  
H. Baneh

Abstract. The aim of the present study was to estimate (co)variance components and corresponding genetic parameters for birth weight (BW), weaning weight (WW), 6-month weight (W6), 9-month weight (W9), average daily gain from birth to weaning (WWDG), average daily gain from weaning to 6 months (W6DG) and average daily gain from 6 months to 9 months (W9DG) for a nucleus flock of Iranian Makooei sheep. Genetic parameters were estimated by REML procedure fitting six animal models including various combinations of maternal effects. The Akaike information criterion (AIC) was used to determine the most appropriate model. Estimates of direct heritability (h2) ranged from 0.13 (W6DG) to 0.32 (BW). Maternal effects were found to be important in the growth performance of the Makooei sheep, indicating the necessity of including maternal effects in the model to obtain accurate estimates of direct heritability. Estimates of maternal heritability (m2) ranged from 0.05 (W6) to 0.16 (WWDG) and the estimates of proportion of maternal permanent environmental variance to phenotypic variance (c2) were in the range between 0.05 (BW) and 0.10 (W6). Direct additive genetic correlations were positive in all cases and ranged from 0.00 (BW/W9DG) to 0.99 (WW/WWDG). Phenotypic correlations showed a broad range from −0.27 (WW/W9DG) to 0.99 (WW/WWDG). Estimates of genetic parameters showed that genetic improvement through selection programs is possible. WW would be a suitable selection criterion since it has acceptable direct heritability and relatively high genetic correlation with other traits.


2017 ◽  
Vol 57 (2) ◽  
pp. 209 ◽  
Author(s):  
D. J. Brown ◽  
N. M. Fogarty

Breeding Merino sheep that are resistant to internal parasites alleviates the high costs associated with treatment of worm infestation and loss of production, as well as mitigating the development of anthelmintic resistance among the major worm species. Faecal worm egg count ((cube root transformation), wec) can be used in sheep as a measure of internal parasite resistance. Accurate estimates of genetic parameters for wec are required for calculation of Australian Sheep Breeding Values and inclusion of worm resistance in sheep breeding programs. This study provides updated estimates of heritability for wec and its genetic correlations with production traits. Data were analysed from a wide range of Australian and New Zealand Merino sheep in the MERINOSELECT database, which included 141 flocks with 801 flock years and up to 217 137 animals with wec recorded in at least one of four ages (W = weaning, P = post weaning, Y = yearling, H = hogget). The heritability estimates ranged from 0.16 ± 0.01 for Ywec to 0.29 ± 0.01 for Wwec, with generally high genetic correlations between the ages. Bivariate analyses estimated genetic correlations between wec at the various ages and growth, carcass quality, reproduction and wool production traits at various ages. These genetic correlations were generally small or close to zero, albeit with some significantly different from zero. The moderate heritability for wec (0.2–0.3) and its high phenotypic variation (coefficient of variation >30%) shows that relatively rapid selection response for worm resistance could be achieved. Inclusion of wec in sheep breeding programs to increase worm resistance would be expected to have little if any impact on other important production traits. These genetic parameters have been incorporated into MERINOSELECT by Sheep Genetics to provide Australian Sheep Breeding Values for wec and appropriate indices for wool and meat production. There is evidence that genotype × environment interactions may be important in some environments by reducing the accuracy of Australian Sheep Breeding Values for wec. Hence it may be prudent for breeders to implement strategies that manage the risk of any impact of genotype × environment on their breeding program.


1998 ◽  
Vol 66 (3) ◽  
pp. 577-584 ◽  
Author(s):  
J. E. Pryce ◽  
R. J. Esslemont ◽  
R. Thompson ◽  
R. F. Veerkamp ◽  
M. A. Kossaibati ◽  
...  

AbstractThe Dairy Information System (DAISY) was developed to record fertility and health information for use in research and to help farmers manage their farms. Data from 33 herds recording health and fertility over a 6-year period were used to study genetic relationships of several health, fertility and production traits. There were 10 569 records from 4642 cows of all parities. These were used to estimate genetic parameters for health: mastitis, lameness and somatic cell score (SCS), for fertility: calving interval, days to first service, conception to first service and for production: 305-day milk, butterfat and protein yields. Heritabilities for these traits were also estimated for the first three lactations. (Co)variances were estimated using linear, multitrait restricted maximum likelihood (REML) with an animal model. Mastitis and lameness were treated as all-or-none traits. The incidence of these diseases increased with lactation number, which may lead to variance component estimation problems, as the mean is linked to the variance in binomial distributions. Therefore, a method was used to fix the within-lactation variance to one in all lactations while maintaining the same mean. The heritability for SCS across lactations was 0·15. Heritabilities for other health and fertility traits were low and ranged between 0·013 and 0·047. All genetic correlations with the production traits were antagonistic implying that selection for yield may have led to a deterioration in health and fertility. The genetic correlation between SCS and mastitis was 0·65 indicating that indirect selection for improvements in mastitis may be achieved using somatic cell counts as a selection criterion. The potential use of linear type scores as predictors of the health traits was investigated by regressing health traits on sire predicted transmitting abilities for type. The results indicate that some type traits may be useful as future selection criteria.


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