• Journal of Animal Science and Technology
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• v.50 no.2
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• pp.157-166
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• 2008

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.1
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• pp.53-59
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• 2000

Data from a village household dairy survey was compared with technical parameters of three model farms (0.2, 0.4 and 0.8 ha in extent) established by the Mid-country Livestock Development Centre (MLDC). In terms of land size, about 67% of the 250 dairy farmers interviewed corresponded with the MLDC models, but only 33% of the farmers were keeping dairy cattle under conditions comparable to the MLDC models (no regular off-farm income). In the 0.2 ha category, village farmers kept more cows, and in the other two categories the village farmers kept less cows than their MLDC model counterparts. In all three categories, the milk production per cow was higher in the model farms (1540 to 2137 vs. 1464 to 1508 litres/cow/year), and this could be attributed to higher feeding levels of concentrates in the model farms as compared to the village farmers (430 to 761 vs. 233 to 383 kg/cow/year). The amount of milk produced from fodder was higher in the village situation in comparison to the models. In the mid country, dairy production seems to depend on access to fodder resources rather than on the extent of land owned. Except in the 0.8 ha village category, the highest contribution to the total income was made by the dairy component (44 to 60%). With 0.8 ha village farmers, the income contribution from dairy and crops was similar (41%). Income from other livestock was important for the 0.2 ha MLDC model, but for all other categories their contribution to total income ranged from 0 to 10%. Access to fodder resources outside own-farm land is vital for economic dairy production. As such, an in-depth analysis of feed resources available and their accessibility needs to be further investigated.

• Journal of the Korean Data and Information Science Society
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• v.27 no.3
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• pp.741-747
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• 2016

The aim of study was to estimate genetic parameter of carcass traits in commercial Hanwoo steer using national animal model for selection of superior bull. Analyzed data (n=5,843) on carcass traits was collected from 107,020 Hanwoo steer. The animal model was used to estimate heritability and genetic correlations. The estimated heritability of carcass traits were 0.19, 0.17, 0.20 and 0.23 for carcass weight, eye muscle area, backfat thickness and marbling score, respectively. The estimated heritability for carcass traits in commercial Hanwoo are low than estimated heritability of national progeny test population for selection of superior bull because breeding environment, genetic performance of cow and feeding day was different. Therefore, we suggests that animal model can include practical genetic variable based on national animal model to improve genetic performance in commercial Hanwoo.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.8
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• pp.1178-1181
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• 2002

Records from a total of 202 crossbred pigs were classified by their ear type and coat color to examine the presence of interrelationships with growth performances. Crossbred pigs were F2 generations of full sib family out of ten Landrace sows bred by 5 Korean domestic boars. Heavily drooped ear type was predominant, 195 out of 202 pigs over the other two types (1 straight and 6 slightly drooped). Coat colors were classified as four categories, all white, all black, dominant white or dominant black. Ratio among coat color categories did not fall within Mendelian principle of independence regarding two loci involved. There was dependency between ear type and coat color. However, due to rarity of ear types other than heavy drooped, dependency comes from distribution of those rare ear types. Three least squares models to test the effect of ear type and coat colors on growth performances were analyzed. First model analyzed effects on birth weight, body weight at 3 and 6 weeks and ADG' before weaning and between 3 and 5 weeks of age. This model included sex in addition to ear type and coat color. Second model analyzed postweaning growth traits (initial weight, final weight and ADG between these periods) upon initiation of performance testing. This model included effects of sex, test group and start age (as a covariate) in addition. Third model was fit for fasted weight before slaughter and included the effects of sex, test group and age at slaughter (as a covariate). The effects of sex and ear type were not significant source of variation for all traits. Test group was a significant source of variation for all the postweaning traits. Effect of coat color was not significant until the initiation of performance testing and became significant then after. Least squares means of dominantly black pigs were significantly lower than the other three coat colored pigs in final weight around 195 days of age and in ADG from the start of performance test and final weight measure.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2005.10a
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• pp.112-112
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• 2005

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.112-112
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• 2005

• 대한생식의학회:학술대회논문집
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• 2000.02a
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• pp.229-234
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• 2000

Transgenic animal technology has provided new opportunities in many aspects of biotechnology and medicine during two decades. Several gene delivery systems including pronuclear injection, retroviral vectors, sperm vectors, and somatic cell cloning have been tried to generate new functional animals. In the future somatic cell cloning technology will be a major method in the transgenic animal production. Many factors enhancing overall transgenic efficiency should be overcome to facilitate the industrial applications of transgenic technology. Transgenic animal technology has settled down in some areas of the medicine, especially the mass production of pharmaceutical proteins and xenotransplantation. Thus, animal biotechnology will contribute to welfare of human being.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.9
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• pp.1252-1258
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• 2015

The Liangshan pig is a traditional Chinese small-sized breed; it has a relatively long feeding period and low meat production ability but superior meat quality. This study utilized three non-linear growth models (Von Bertalanffy, Gompertz, and logistic) to fit the growth curve of Liangshan pigs from an unselected, random-bred pig population and estimate the pigs most suitable slaughter weight. The growth development data at 20 time points of 275 Liangshan pigs (from birth to 250 d) were collected. To analyze the relative gene expression related to development, seven slaughter weight phases (50, 58, 66, 74, 82, 90, and 98 kg) (20 pigs per phase) were examined. We found that the Liangshan pig growth curve fit the typical S-curve well and that their growth turning point was 193.4 days at a weight of 62.5 kg, according to the best fit Von Bertalanffy model based on the goodness of fit criteria. Furthermore, we estimated that the most suitable slaughter weight was 62.5 to 74.9 kg based on the growth curve and the relative expression levels of growth-related genes.

• Journal of Animal Science and Technology
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• v.63 no.6
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• pp.1211-1222
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• 2021

Data of 651 lambs (68 Romanov, 49 Rahmani, 151 [♀1/2 Rahmani × ♂1/2 Romanov) and 383 (♀3/4 Rahmani and 1/4♂ Romanov]) were collected from Mehalet Mousa Farm, belonging to Animal Production Research Institute from the period of 2009 to 2016 to estimate phenotypic and genetic parameters. The traits studied were birth weight (BW), body weight at four week (BW4), body weight at eight weeks (BW8) and body weight at twelve weeks (BW12) or weaning weight. Least squares analysis of variance shows significance of the effects of breed groups, gender of lambs, birth type; month of birth and year of birth on all traits studied. Rahmani lambs had heavier BW, BW4, BW8 and BW12 while Romanov lambs had the lowest ones. The first generation (♀1/2 Rhamani × ♂1/2 Romanov) had heavier body weights than Romanov and the second generation (♀3/4 Rahmani × ♂1/4 Roamnov). Gender of lambs had highly significant effect on body weights. Males were significantly (p < 0.01) heavier than females for all traits studied. Least square means of BW, BW4, BW8 and BW12 for single lambs were 2.69, 10.43, 13.53 and 16.10 kg, respectively. Least square means of BW, BW4, BW8 and BW12 for twin lambs were 2.50, 9.37, 12.5 and 15.16 kg, respectively, while least square means of BW, BW4, BW8 and BW12 for triple lambs were 2.09, 7.86, 10.83 and 13.67 kg, respectively. Estimates of direct heritability measured by single trait animal model were 0.14, 0.23, 0.25 and 0.26 for BW, BW4, BW8 and BW12, respectively, and the corresponding measured by multi trait animal model were 0.17, 0.24, 0.32 and 0.36 for the same traits, respectively. All genetic and phenotypic correlations among different traits studied are positive and significant.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.1
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• pp.122-133
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• 1997

Purified diets containing 5 graded levels of threonine were fed to young, growing and finishing pigs to determine the threonine requirement for growth and maintenance. A model was developed to subdivide the threonine requirement for the maintenance from the requirement for growth. From this model, the threonine requirement for growth was 7.733, 10.968 and 11.235 g/kg live weight gain and the maintenance requirement was 0.118, 0.048 and 0.024 g per unit of metabolic body size at each stage of growth, respectively. In the young pigs, the threonine requirement for growth was 0.388 g/g N gain and the maintenance requirement was 0.122 g per unit of metabolic body size. The breakpoint of plasma threonine concentrations was 3.995, 7.933 and 7.738 g/d, respectively. Expected requirements obtained from these formulae were in general agreement with previous estimates. Based on the weight gain vs N gain equation, about 4.24% of the retained protein was comprised of threonine and compared to 3.81%, the mean threonine content of pig muscle CP.