• Journal of Animal Science and Technology
• /
• v.45 no.5
• /
• pp.679-688
• /
• 2003

The leptin receptor gene(LEPR) produces a high affinity receptor that mediates the regulation of the leptin gene. Leptin secreted from adipose tissue plays an important role in regulating feed intake and energy balance. In this study, a microsatellite marker within LEPR was selected and genotyped for the F2 population composed of 354 individuals from an intercross between Korean Native boars and Landrace sows. Totally, six alleles (255, 259, 261, 263, 265 and 267bp) and nineteen genotypes were detected in the population, of which the CE (261/265), CC (261/261) and EE (265/265) types were observed by 20.0%, 10.1% and 9.6%, respectively. Relationships between their genotypes and economic traits were analyzed. We found specific genotypes associated with economic traits such as body weight at 12 weeks of age/body fat including abdominal and trimmed fat/shear force (P〈0.001), body weight of 30 weeks of age (P〈0.01) and body weight of 3 weeks of age/back fat thickness (P〈0.05). The DD (263/263) and DF (263/267) types were associated with body weight at 3, 5, 12 and 30 weeks of age. The DF (263/267) type showed a highly significant effect on back fat thickness and body fat including abdominal and trimmed fat. The DF (263/267) type showed positive effect on shear force, whereas the BB (259/259) and DD (263/263) types negatively affected on tenderness.

• Food Science of Animal Resources
• /
• v.28 no.2
• /
• pp.187-195
• /
• 2008

The purpose of this study was to establish proper shipping weight and backfat thickness by applying the growth model to backfat thickness, measured by means of not only body weight, but also ultrasonography, and predicting the changes by age. Three breeds, i.e. Duroc, Landrace, and Yorkshie, were analyzed, and the Gompertz, logistic, and Von Bertalanffy model were used for inference with the parameter of the growth model being sex. As a result, both body weight and backfat thickness showed different growth curve parameters and characteristics at inflection points depending on model selection and sex. As for backfat thickness, in estimating the inflection point, unlike the case of body weight, the inflection ages of the boars of the Duroc breed was earlier than that of sows, whereas the inflection ages of the sows of the Landrace and Yorkshire breeds was earlier than that of boars. More than anything else, in the analysis of the changes in backfat thickness according to body weight, as the body weight reached 145kg, the backfat thickness showed much variation as great as 1.7-3.2 cm in each breed and sex. In addition, unlike the other breeds, the boars of the Landrace breed showed an exponential type of relationship between body weight and backfat thickness. As they grow to become 100 kg or heavier, abrupt change in back fat thickness was confirmed. If the growth of body weight and backfat thickness is understood and the genetic relationship is taken advantage of like this, it would be possible to set desired body weight and backfat thickness, and thus help effectively set the shipping time. If not only the phenotype, but also genetic parameters about growth characteristics are estimated and analyzed additionally, more effective data can be generated.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.5
• /
• pp.770-777
• /
• 2020

Objective: This study was conducted to determine early hereditary endowment to establish a short-term feeding program. Methods: Hanwoo steers (n = 140) were equally distributed into four groups (35/group) based on genetic meat yield index (MYI) viz. the greatest, great, low, and the lowest at Jukam Hanwoo farm, Goheung. All animals were fed in group pens (5 animals/pen) with similar feed depending on the growth stage. Rice straw was provided ad libitum, whereas concentrate was fed at 5.71 kg during the growing period (6 to 13 mo) and 9.4 kg during the fattening period (13 to 28 mo). Body weight (BW) was measured at two-month intervals, whereas carcass weight was determined at slaughtering at about 31 months of age. The Affymetrix Bovine Axiom Array 640K single nucleotide polymorphism (SNP) chip was used to determine the meat quantity-related gene in the blood. Results: After 6 months, the highest (p<0.05) BW was observed in the greatest MYI group (190.77 kg) and the lowest (p<0.05) in the lowest MYI group (173.51 kg). The great MYI group also showed significantly (p<0.05) higher BW than the lowest MYI group. After 16 and 24 months, the greatest MYI group had the highest BW gain (p<0.05) and were therefore slaughtered the earliest. Carcass weight was significantly (p<0.05) higher in the greatest and the great MYI groups followed by the low and the lowest MYI groups. Back-fat thickness in the greatest MYI group was highly correlated to carcass weight and marbling score. The SNP array analysis identified the carcass-weight related gene BTB-01280026 with an additive effect. The steers with the allele increasing carcass weight had heavier slaughter weight of about 12 kg. Conclusion: Genetic MYI is a potential tool for calf selection, which will reduce the slaughter age while simultaneously increasing carcass weight, back-fat thickness, and marbling score.

• Journal of Animal Science and Technology
• /
• v.48 no.5
• /
• pp.663-670
• /
• 2006

The present study was performed to investigate the effect of plant type recombinant porcine somatotropin (pST) adminstration on growth performance and blood profile of finishing pigs. Forty-eight Landrace barrows weighing 78 kg were employed for six week growth trial. Twelve barrows were allocated into various rpST types ; the control (CONT), the 4:1 type rpST (TRT 1), the 1:1 type rpST (TRT 2); and the 4:1 type rpST group(TRT 3) respectively. CONT group were not planted rpST. TRT 1 group was treated with rpST once a week for 6 weeks. Each dose contained the rpST equivalent to 100mg from initial to two weeks and 125mg from three weeks to finial week. TRT 2 and TRT 3 groups were planted rpST four times contained the rpST equivalent to 100mg during trial period from initial to two weeks, and 125 mg from three weeks, to four weeks, respectively. All pigs were fed a commercial feed containing 0.9% lysine ad lib. Daily gain increased by 19.4% in TRT 1(p<0.05) compared to the CONT. rpST improved feed/gain by 13.4～28.9% in all treatment groups(p<0.05). Back fat thickness of the all rpST treated groups were 23.3～29.2% thinner than that of the CONT. These results indicated that the rpST stimulated growth performance in finishing pigs and plant type rpST could be used as a growth stimulant for finishing pigs.

• Journal of Life Science
• /
• v.32 no.4
• /
• pp.279-284
• /
• 2022

This study was conducted to establish a genetic evaluation system applicable to general farms for improving cows raised on farms. The analysis used Best Linear Unbiased Prediction (BLUP) and Genomic Best Linear Unbiased Prediction (GBLUP) for 619 cows raised in Gyeonggi-do Province and compared and analyzed the accuracy of the estimated breeding value according to four traits (carcass weight, loineye muscle area, back fat thickness, and marbling). In the case of the GBLUP method, the size of the reference population was divided into different four groups and analyzed. The analysis results confirmed that the accuracy of the breeding value of each trait increased as the size of the GBLUP reference population increased. Comparing the accuracy of the breeding values estimated using the BLUP and GBLUP methods, it was confirmed that when the breeding values were estimated using the GBLUP method, they increased by 0.10, 0.09, 0.09, and 0.11 for carcass weight, eye muscle area, back fat thickness, and marbling scores, respectively. Applying the GBLUP method to the evaluation and selection of cows can enable precise and accurate individual selection, while increasing the size of the reference population can make even more accurate individual selection possible, thus increasing selection efficiency.

• Food Science of Animal Resources
• /
• v.44 no.1
• /
• pp.51-73
• /
• 2024

This study investigated how birth weight differences in piglets affected carcass and muscle fiber properties as well as meat quality at slaughter. Within litters, piglets were grouped according to their birth weight as either normal (NBW; 1.62-1.73 kg) or low (LBW; 1.18-1.29 kg). At 5 weeks of age, NBW piglets were randomly transitioned to control (C) or isocaloric high fat diets derived from non-dairy (HF), while LBW piglets were randomly transitioned to high fat diets derived from non-dairy (HF) or dairy sources (HFHD). Piglets were reared in individual pens under standardized housing and feeding conditions. Live weight was recorded weekly, and pigs were slaughtered at 12 weeks of age. Hot carcass weights, dressing percentages, lean meat yield, and primal cut proportions were determined. The m. longissimus thoracis was collected from the right side of the carcass for measurement of physical and chemical properties of meat and muscle fiber characteristics. Results indicated that LBW pigs compensated for their live weight compared to NBW pigs at 6 weeks of age. The mean muscle fiber diameter of LBW-HFHD group is significantly higher than NBW-C and NBW-HF group, and the type I muscle fiber diameter is significantly higher than NBW-C group. Dairy fat inclusion in LBW pig diet reduced carcass back fat thickness. This increased the calculated lean meat yield to be comparable to that of NBW pigs fed a commercial diet. Incorporating dairy-sourced high-fat into LBW pigs' diets appears to be an effective strategy for producing carcasses equivalent to NBW pigs.

• Asian-Australasian Journal of Animal Sciences
• /
• v.26 no.11
• /
• pp.1630-1636
• /
• 2013

An investigation was carried out to assess the carcass characteristics and meat quality aspects of immunocastrated male pigs of medium genetic potential for lean meat deposition in carcass (53 to 55%). When the crossbred Large White x Landrace pigs (n = 45) were 70 days old, they were distributed in a totally randomized design in three treatments (castrated males, females and immunocastrated males) with three replicates of five animals. The pigs were slaughtered when they were 140 days old. Carcass temperature and pH were recorded twice, at 45 min and 24 h after slaughter. The carcasses were evaluated for hot and cold carcass yield, commercial cuts yield, length and depth, back fat thickness, loin eye area and lean meat percentage. The Longissimus dorsi muscle was extracted for analysis of color ($L^*$, $a^*$, $b^*$), exudate loss, cooking loss and centesimal and sensorial analysis of the meat. There were no significant differences for the evaluated parameters between castrated males, immunocastrated males and females, except for backfat thickness between the 7th and 8th thoracic vertebra and the point P2 (lower for immunocastrated males) and carcass temperature at 45 min post slaughter (higher in immunocastrated males), however, this did not interfer with the rate of pH decrease post mortem and the meat quality. The results from this research did not indicate a benefit of immunocastration on carcass characteristics of pigs of medium genetic potential for lean meat deposition in carcass, when compared to surgical castration.

• Journal of Animal Science and Technology
• /
• v.47 no.1
• /
• pp.57-72
• /
• 2005

The present study was undertaken to investigate the effects of nutrient density diets and sex on carcass and pork quality characteristics in finishing pigs. A total of 96 pigs(58.04 $\pm$ 6.85 kg) were divided into 2 groups(gilts and barrows), each sex group was assigned to 3 nutrient density(high : 18.5%, middle : 16.0% and low: 14.0% CP, respectively) and raised up to 1l0kg live weight. Each treatment had four replicates with three or five pigs per replicate. The treatments comprised the feeding regimes of 1) the low density diet for 60 days, 2) the middle nutrient density diet for the 30 days followed by a low nutrient density diet for the remaining 30 days and 3) the high nutrient density diet for the 30 days followed by a middle nutrient density diet for the remaining 30 days. Pigs were conventionally slaughtered, and then chilled overnight. Carcass characteristics and grades were determined on those carcasses, and pork loin muscle was removed from each left side at 5th to 13th rib for quality evaluation were evaluated. There were no differences in the carcass weight between sex and nutrient density. Dressing percent of L-L(gilts) treatment was significantly higher than that of other treatments(P< 0.05). Barrows showed a thicker back fat thickness than gilts. There were no difference in intramuscular fat, subcutaneous fat and springiness between sex and nutrient density. Intermuscular fat of barrows groups was significantly higher than the gilts groups(P < 0.05). In the meat quality characteristics, there were no difference in general composition, meat and fat color between sex and nutrient density. pH of L-L(gilts) treatment was significantly higher than that of other treatments(P < 0.05). Cooking loss and shear force value of H-M(barrows) treatment were significantly higher than those of other treatments(P< 0.05). Purge loss of barrows groups was significantly higher than the gilts groups(P < 0.05). Myoglobin content of H-M treatment was significantly lower than L-L and M-L treatments(P< 0.05). Texture of H-M treatment was higher than L-L and M-L treatments. The content of myristic, palmitic, palmitoleic and oleic acid were significantly higher in the barrows groups(P< 0.05). However, stearic, linoleic and arachidonic acid were significantly higher in the gilts(P < 0.05). Amino acid content of L-L treatment was significantly higher than M-L and H-M treatments(P < 0.05). In conclusion, carcass and pork quality characteristics were affected by sex and nutrient density.

• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.11
• /
• pp.1592-1598
• /
• 2015

This study was conducted to determine the effects of feeding a trace minerals-fortified microbial culture (TMC) on the performance and carcass characteristics of late-fattening Hanwoo steers. A mixture of microbes (0.6% [v/w] of Enterobacter sp., Bacillus sp., Lactobacillus sp., and Saccharomyces sp.) was cultured with 99% feedstuff for ensiling and 0.4% trace minerals (zinc, selenium, copper, and cobalt). Sixteen late-fattening steers (mean age, 21.8 months) were allocated to two diets: a control diet (concentrate mix and rice straw) and a treated diet (control diet+3.3% TMC). At a mean age of 31.1 months, all the steers were slaughtered. The addition of TMC to the diet did not affect the average daily weight gain of the late fattening steers, compared with that of control steers. Moreover, consuming the TMC-supplemented diet did not affect cold carcass weight, yield traits such as back fat thickness, longissimus muscle area, yield index or yield grade, or quality traits such as meat color, fat color, texture, maturity, marbling score, or quality grade. However, consumption of a TMC-supplemented diet increased the concentrations of zinc, selenium, and sulfur (p<0.05) in the longissimus muscle. With respect to amino acids, animals consuming TMC showed increased (p<0.05) concentrations of lysine, leucine, and valine among essential amino acids and a decreased (p<0.05) concentration of proline among non-essential amino acids. In conclusion, the consumption of a TMC-supplemented diet during the late-fattening period elevated the concentrations of certain trace minerals and essential amino acids in the longissimus muscle, without any deleterious effects on performance and other carcass characteristics of Hanwoo steers.

• Korean Journal of Agricultural Science
• /
• v.42 no.3
• /
• pp.253-259
• /
• 2015

This study was conducted to investigate the effect of different additives on the growth performance, feed efficiency and carcass characteristics in Holstein steers during 18month fattening periods. Twenty four Holstein steers, 5months of age and 176.6kg, were randomly allocated to 3 experimental groups 8 animals each for 18-months feeding trial. The groups were control (not additive), T1 (fed zinc, Vitamin C) and T2 (fed zinc, Vitamin C, Vitamin B6 and Selenium). According to feeding additives, final weight was not significantly different among the treatment groups, tended to be high at T2 group (827kg) compared to the other groups. Average daily gain was not different among the treatment groups during the experimental periods, but T2 group was significantly greater than T1 group in growing stage (p<0.05). The feed additives had no effects on DMI during experimental periods. Feed conversion ratio of T1 group in growing stage was significantly higher than those of other groups (p<0.05), average feed conversion ratio was tend to be decreased at T2 group rather compared with other groups. In the results of yield traits, carcass weight were relatively higher in T2 group than other groups (p<0.05). Rib-eye area, back fat thickness and yield index were similar between groups. In quality traits, marbling, meat color, fat color, texture and maturity were not significantly different among the groups. In economic efficiency, income was highest at T2 group as 91~393 thousand won among 3 groups.