Journal of Animal Science and Technology (JAST) is a peer-reviewed, open access journal publishing original research, review articles and notes in all fields of animal science. Topics covered by the journal include: genetics and breeding, physiology, nutrition of monogastric animals, nutrition of ruminants, animal products (milk, meat, eggs and their by-products) and their processing, grasslands and roughages, livestock environment, animal biotechnology, animal behavior and welfare.

This experiment was conducted to evaluate the effects of dietary protease on growth performance, blood constituents, and carcass characteristics of growing-finishing pigs. A total of 48 growing pigs (initial body weight, 34.8 ± 0.62 kg) were randomly assigned to 2 dietary treatments (6 pigs/pen; 4 replicates/treatment). The treatments were a diet based on corn and soybean meal (CON) and CON supplemented with 0.01 % of protease (PRO). Pigs were fed respective dietary treatments with a 2-phase feeding program for 12 weeks. Pigs fed PRO had higher average daily gain (ADG; phase I, 866.38 vs. 821.75 g/d; overall, 910.96 vs. 866.30 g/d; p < 0.05) and gain to feed ratio (G:F; phase I, 0.345 vs. 0.363 g/g; p < 0.05) than those fed CON. However, there were no differences on blood constituents and carcass characteristics between CON and PRO of growing-finishing pigs. In conclusion, dietary protease supplementation in the typical diet for growing-finishing pigs improved growth rate.

Journal of Animal Science and Technology (JAST) is a peer-reviewed, open access journal publishing original research, review articles and notes in all fields of animal science. Topics covered by the journal include: genetics and breeding, physiology, nutrition of monogastric animals, nutrition of ruminants, animal products (milk, meat, eggs and their by-products) and their processing, grasslands and roughages, livestock environment, animal biotechnology, animal behavior and welfare.

Journal of Animal Science and Technology (JAST) is a peer-reviewed, open access journal publishing original research, review articles and notes in all fields of animal science. Topics covered by the journal include: genetics and breeding, physiology, nutrition of monogastric animals, nutrition of ruminants, animal products (milk, meat, eggs and their by-products) and their processing, grasslands and roughages, livestock environment, animal biotechnology, animal behavior and welfare.

Objective: For decades, LYD ([Landrace×Yorkshire] ♀×Duroc ♂) pigs are the most commonly-used commercial breed for meat production in Korea. Recently, due to the increasing demand for premium pork, the National Institute of Animal Science (Korea) has synthesized a novel pig breed named Woori Heukdon (WHD). This study aimed at comparing the carcass traits, meat yield and quality characteristics between the LYD and WHD pigs under identical rearing condition.Methods: The WHD and LYD pigs (n = 15 each) were reared under identical conditions and fed the same commercial diet until reaching recommended market weight (100 to 120 kg). After slaughter, the carcasses were evaluated for traits and meat yield, and the meat quality was assessed on shoulder butt and belly cuts.Results: Although no significant differences (p>0.05) occurred in slaughter weight between two pig types, WHD had a lower meat yield (by about 6 kg corresponding to approximately 7%) compared to the LYD pigs (p<0.05). The WHD had a higher fat content (by 4.26% and 13.52% in the shoulder butt and belly, respectively) compared to those of LYD pigs (p<0.05). The WHD meat showed a lower cooking loss and higher a* (redness) value (p<0.05). The WHD belly had a significantly (p<0.05) higher oleic acid content and concentrations of nonanal, octanal and decanal associated with fatty odor while, the LYD meat had a higher number of pyrazines associated with roasty odor. Regarding sensory quality, higher flavor, juiciness, and acceptability higher scores were given for the WHD meat than for the LYD meat (p<0.05).Conclusion: Under identical rearing conditions the WHD exhibited a better meat quality and sensory properties. However, the use of this diet resulted in a high fat level that may be associated with high trimming loss for the WHD.

This study was conducted to provide commercial pig farms with information about group housing systems for sows in accordance with the amendment of the prohibition law for individual stalls for sows in South Korea. Therefore, this experiment was performed to compare the effects of individual stalls (IS) and group housing systems (GS) on the productivity of sows to investigate the feasibility of replacing individual stalls with group housing systems in commercial sow units. Forty primiparous sows (Landrace × Yorkshire; 210.67 ± 2.22 kg average initial body weight) were randomly assigned to four treatments with restricted feeding after 8 weeks from artificial insemination. The four treatments were (i) individual stalls (IS; housed in pen stalls), (ii) short stalls (SS; sows housed in pens with non-gated feeding stalls), (iii) free access stalls (FAS; a non-competitive housing system), and (iv) electronic sow feeders (ESF; used with radio frequency identification technology to allow individual sow management without individual confinement). All sows were transferred to farrowing crates at 110 days of gestation. There were no differences in sow productive performance, reproductive performance, and colostrum composition between IS and GS and among GS. The considered GS did not negatively affect any productivity parameters of primiparous sows compared with IS; the GS could replace IS in commercial sow units.