• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.8-12
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• 2005

Response in a modified reciprocal recurrent selection scheme for egg production was evaluated considering variable family sizes and genetic correlation between purebred and crossbred half sisters. The criteria of selection of purebred breeders included pullet's own performance, purebred full and half sisters and crossbred half sister's performance. Heritability of egg production of crossbreds (aggregate genotype) and purebred's was assumed to be 0.2 and genetic correlation between purebred and crossbred half sisters ($r_{pc}$) as 0.1, 0.2, 0.3, 0.4, 0.5, 1.0, -0.1, -0.2, -0.3, -0.4, -0.5 and -1.0. Number of dams per sire to produce purebred and crossbred progenies assumed to be 5, 6, 7, 8, while number of purebred female progeny ($N_p$) and crossbred progeny ($N_c$) per dam were considered to be 3, 4, 5 and 6 in each case. Considering phenotypic variance as unity, selection indices were constructed for different combinations of dams and progeny for each value of $r_{pc}$. Following selection index theory, response in crossbred and purebred for egg production was computed. Results indicated that response in crossbreds depended mainly on crossbred family size and also on magnitude of$r_{pc}$ irrespective of its direction, and response was greater with large crossbred family size than the purebred families. Correlated response in purebreds depends both on magnitude and direction of $r_{pc}$ and was expected to be greater with large purebred family size only. Inclusion of purebred information increased the accuracy of selection for crossbred response for higher magnitude of$r_{pc}$ irrespective of its direction. Present results indicate that desirable response in both crossbred and purebred performance is a function of $r_{pc}$ and family sizes. The ratio of crossbred and purebred family sizes can be optimized depending on the objective of improving the performance of crossbreds and/or of purebreds.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.7
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• pp.954-959
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• 2004

In a herd of 24 spring-born steers, plasma leptin and performance of selected purebred (n=5) and backcrossed Hereford (n=5) were compared in a year-round summer grazing and winter feedlot fattening. Bimonthly blood collection and body weight measurement were accomplished. The plasma samples were analyzed for leptin, insulin, total cholesterol, triglyceride, NEFA and glucose. The experimental design utilized one-way ANOVA with breed as the treatment. The purebred obtained higher plasma NEFA (p<0.001) compared to backcross, regardless of seasonal feeding systems (SFS). The backcross showed gradual increase and nonresponsiveness of plasma leptin to SFS. During summer grazing, attenuation of plasma leptin and sudden elevation when shifted to winter feedlot fattening were observed in purebred. Plasma leptin obtained linear relationship with body weight of purebred (r=0.53;p<0.001) and backcrossed Hereford (r=0.49; p<0.01). The purebred and backcrossed Hereford, when shifted to summer grazing, resulted to sustained and restricted daily gain, respectively. Therefore, cattle breeds of higher growth potential exhibit significant elevation of plasma leptin after 400 kg BW, when animal starts to deposit significant body fat.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.2
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• pp.143-150
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• 1991

The data on reproductive performance of 1065 purebred Landrace, 1254 purebred Yorkshire. 553 purebred Duroc and 327 purebred Pietrain sows bred to farrow purebred litters and data from 3413 Landrace $\times$ Yorkshire, 487 Duroc $\times$ Pietrain and 3191 commericial litters were udsed in this study. The data were collected form litters farrowed form January 1986 to December 1988 in Holiday Hills Stock and Breeding Farms, San Prero, Laguna. The crossbred sows and litters were better in most traits associated with sow productivity than their contemporary purebred sows and litters. The Duroc $\times$ Pietrain crossbred litters showed 16.67% improvement in litter size at weaning, 10.11% improvement in survival rate form birth to weaning and 16.21% more pigs per sow pre year than the averages of their parental breeds. The litters from the Landrace $\times$ Yorkshire crossbred sows sired by either Duroc or Duroc $\times$ Pietrain boars had 11.01% bigger litter size at birth, 20.74% increase in litter size at weaning and 22.86% more pigs weaned per sow per year than the averages of the four parental breeds. Very little improvement in most traits evaluated were observed form the Landrace $\times$ Yorkshire crossbred litters compared with their parental breeds. Year of birth of litter had litter influence on sow productivity. However, the reproductivity performance declined when sows farrowed in June up to September. The best Months of farrowing were found to be from January to April. The breed $\times$ year, breed $\times$ month and year $\times$ month had no significant effects on all traits evaluated.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1093-1101
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• 2003

Reproductive data, such as numbers of days to the first estrus and A.I. service postpartum, number of days to conception, number of A.I. services required for conception, interval between the first estrus and first A.I. service and the average interval of A.I. service in Thai native-Friesian crossbred and pure Friesian dairy cows, were compiled in the National Dairy Training and Applied Research Institute in Chiang Mai, Thailand. The data were analyzed statistically and the effect of milk production on these reproductive traits was investigated. The reproductive efficiency of purebred cows was obviously inferior when compared with crossbred animals, in spite of special care being given to the purebred only in order to alleviate the effect of a tropical climate and provide better feeding. However, the regression analysis between reproductive and lactational parameters revealed a definite antagonistic effect of lactation on reproduction, especially in the purebred cows, which had a larger amount of milk production and longer lactation period. If these effects of lactation were eliminated, there would be no evident difference in reproductive efficiency between purebred and crossbred cows in the conditions of this study. Among the reproductive parameters examined, the number of days to the first estrus and interval between the first estrus and first A.I. service were less affected by breed difference and the magnitude of lactation than other reasons.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.9
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• pp.1316-1322
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• 2000

Data were compiled and statistically analyzed on the lactation of 50% and 75% Thai native-Friesian crossbred and purebred Friesian cows that were fed at a national institute in Chiang Mai, Thailand. More than 30% higher milk production was obtained in the 75% crossbred compared with that in the 50%, but this amount of milk production in the upgraded breed was still about half that of purebred Friesians; 2,138 kg, least squares means during an average lactation period of 279 days in the 50% crossbred, 2,847 kg during 277 days in the 75% crossbred and 5,585 kg during 308 days in the purebred. Environmental stress due to tropical climate was alleviated by the use of electric fans and water sprinklers in the feeding house during the hot season, and improved diet seemed to enable purebred Friesians to keep their ability to produce a milk quantity of more than 6,500 kg per year. This special care was not given to crossbreds and significantly negative correlations were found between daily minimum temperature and humidity during the initial 100 days of lactation and total milk production and average daily milk yield in the 75% crossbreds. However, these correlations were not found in the 50% crossbreds.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.195-198
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• 2011

To screen several promising red pepper cultivars, may be adaptable to organic cultivation conditions, seventy six F1 hybrids commercial and eight local purebred red pepper cultivars were tested. Comparing the infection rate of phytophthora blight between commercial (F1 hybrid) and local (Purebred) cultivars, average infection rate of commercial cultivars was 9.8% and that of local cultivars was 17.8%. But the infected fruits rate of anthracnose in field were similar as 3.3% in commercial (F1 hybrid) and 3.1% in local (Purebred) cultivars. In yield characteristics, average yield of commercial cultivars was 2.89 t $ha^{-1}$ and that of local cultivars was 2.22 t $ha^{-1}$. For organic pepper farmers it is more favourable to cultivation purebred cultivars because they can save to the same quality plant next year's crop. In this study among the local purebred cultivars, two cultivars are promising that their yield near to 3 t $ha^{-1}$ and have disease field resistance.

• Journal of Plant Biotechnology
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• v.36 no.2
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• pp.144-148
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• 2009

The transfer of Mn-Superoxide Dismutase (SOD2) gene, complex gene (SA) of CuZnSOD and ascorbate peroxidase (APX), and NDP kinase 2 (NDPK2) gene into Korean 4 cultivars (cvs. Millenium White, Glory Blue, Glory Red, and Glory Purple) and 15 purebred lines of petunia was conducted using Agrobaterium-mediated technique. Two (Wongyo A2-16 and A2-36) of 15 purebred lines and one (cv. Glory Red) of 4 cultivars were effective for the transfer of SOD2 gene. The putative transgenic plants survived on the 2nd selection medium were 124. From PCR analysis, 118 (derived from 4 cultivars and 2 purebred lines) of 124 plants were confirmed to contain marker (npt II ) gene, while 58 of 118 plants did not have target genes. There were no plants with both npt II and SA genes. Twenty seven of 28 SOD2 transgenic plants were re-confirmed as transformants by Sothern analysis. SOD2 and NDPK2 genes were expressed in the transgenic petunias as the ratio of 77.8 to 100.0 % and 23.5%, respectively. T1 seeds were obtained from 36 acclimated transgenic plants (SOD2 34 plus NDPK2) in a glasshouse by self-pollination.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.9
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• pp.1371-1377
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• 2002

During a 5-yr period, 1994-1998, pre-weaning and weaning data were collected on 591 calves produced by mating either straightbred Jersey, straightbred Limousin or $F_1$ (Limousin${\times}$Jersey) bulls to mature purebred Jersey or Limousin cows. Traits recorded included birth and weaning weight, height, length, girth, fat depth and a measure of muscle (ratio of stifle to hip width expressed as a percentage). All traits were analyzed assuming a model with sire and dam random effects that included effects of year and date of birth, sex, breed and year${\times}$sex interaction. Main effects were generally significant with few exceptions. Direct genetic effects were large for weight, height, girth and muscle with a breed trend from purebred Jersey (small) to purebred Limousin (large). At weaning, the maternal effect of the Jersey dam was positive for weight (10.9${\pm}$4.9 kg), girth (3.7${\pm}$1.0 cm) and muscle (6.0${\pm}$0.9%). Heterosis was highly significant and positive only for fat depth (1.5${\pm}$0.2 mm) with the $F_1$ progeny being the fattest, followed by the backcrosses, then purebred Jersey and purebred Limousin. Also, significant (p<0.001) but negative heterosis was observed for weight, girth and muscle. The change in ranking for fat depth relative to other traits is a reflection of the large heterotic effects relative to direct effects on fat depth. Epistatic effects were not significant on any trait at birth or weaning. This study has indicated the possibility of exploiting the positive heterotic and maternal effects for fat depth and muscularity to meet specific meat quality and quantity demand by consumers.

• Food Science of Animal Resources
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• v.36 no.5
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• pp.689-696
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• 2016

This study was conducted to find pork quality to meet the needs of consumers. Thus, the meat quality and fatty acid composition of longissimus muscles from purebred pigs (Landrace, Yorkshire, and Duroc) and three-way crossbred LYD pigs were compared and evaluated. Chemical compositions of longissimus muscles were significant (p<0.05) different among pigs. Duroc contained significant (p<0.05) higher fat contents than other pigs, whereas significant (p<0.05) higher moisture contents were observed in Landrace, Yorkshire, and LYD pigs compared to those of Duroc pigs. The values of pH_{24 h} and pH_{14 d} were the highest in Landrace pigs. Myoglobin contents of LYD pigs were higher (p<0.05) than those of purebred pigs. Regarding meat color, Duroc and Yorkshire pigs had higher redness values than Landrace and LYD pigs, while Landrace pigs had the lowest (p<0.05) color values among all pigs. There was no significant difference in shear force or water holding capacity (WHC). Duroc pigs maintained the lowest drip loss during 14 d of cold storage. In sensory evaluation, the marbling scores of Duroc pigs were higher (p<0.05) than other pigs. Regarding fatty acid compositions, total USFA, poly-, n-3, and n-6 contents were the highest (p<0.05) in LYD pigs, while total SFA contents were the highest (p<0.05) in Duroc pigs. Based on these results, purebred pigs had superior overall meat quality to crossbred pigs.

• Animal Bioscience
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• v.34 no.6
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• pp.967-974
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• 2021

Objective: The objective of this study was to estimate the genetic correlation (rpc) of growth performance between purebred (Duroc and Korean native) and synthetic (WooriHeukDon) pigs using a single-step method. Methods: Phenotypes of 15,902 pigs with genotyped data from 1,792 pigs from a nucleus farm were used for this study. We estimated the rpc of several performance traits between WooriHeukDon and purebred pigs: day of target weight (DAY), backfat thickness (BF), feed conversion rate (FCR), and residual feed intake (RFI). The variances and covariances of the studied traits were estimated by an animal multi-trait model that applied the Bayesian inference. Results: rpc within traits was lower than 0.1 for DAY and BF, but high for FCR and RFI; in particular, rpc for RFI between Duroc and WooriHeukDon pigs was nearly 1. Comparison between different traits revealed that RFI in Duroc pigs was associated with different traits in WooriHeukDon pigs. However, the most of rpc between different traits were estimated with low or with high standard deviation. Conclusion: The results indicated that there were substantial differences in rpc of traits in the synthetic WooriHeukDon pigs, which could be caused by these pigs having a more complex origin than other crossbred pigs. RFI was strongly correlated between Duroc and WooriHeukDon pigs, and these breeds might have similar single nucleotide polymorphism effects that control RFI. RFI is more essential for metabolism than other growth traits and these metabolic characteristics in purebred pigs, such as nutrient utilization, could significantly affect those in synthetic pigs. The findings of this study can be used to elucidate the genetic architecture of crossbred pigs and help develop new breeds with target traits.