Chul Young Lee

Therapeutic potential of mesenchymal stem cells overexpressing human forkhead box A2 gene in the regeneration of damaged liver tissues.

Background and Aim:  Although a liver transplantation is considered to be the only effective long‐term treatment in many cases of liver diseases, it is limited by a lack of donor organs and immune rejection. As an autologous stem cell approach, this study was conducted to assess whether forkhead box A2 (Foxa2) gene overexpression in bone marrow‐derived mesenchymal stem cells (MSC) could protect the liver from hepatic diseases by stimulating tissue regeneration after cell transplantation.

Effects of dietary supplementation of lipid-encapsulated zinc oxide on colibacillosis, growth and intestinal morphology in weaned piglets challenged with enterotoxigenic Escherichia coli

This study was aimed to evaluate the effect of dietary supplementation of lipid-encapsulated (coated) zinc oxide ZnO on post-weaning diarrhea (colibacillosis) in weaned piglets challenged with enterotoxigenic Escherichia coli (ETEC). Thirty-two 35-day-old weaned piglets were orally challenged with 3 × 10(10) colony forming units of ETEC K88 while eight piglets received no challenge (control). Each eight challenged piglets received a diet containing 100 ppm ZnO (low ZnO), 2500 ppm ZnO (high ZnO) or 100 ppm of lipid (10%)-coated ZnO (coated ZnO) for 7 days; control pigs received the low ZnO diet. Daily gain, goblet cell density in the villi of the duodenum, jejunum and ileum, and villus height in the jejunum and ileum, which decreased due to the challenge, were equally greater in the coated ZnO and high ZnO groups versus low ZnO group. Fecal consistency score, serum interleukin-8 concentration, subjective score of fecal E. coli shedding, and digesta pH in the stomach, jejunum and ileum, which increased due to the challenge, were equally low in the coated ZnO and high ZnO groups versus low ZnO. Results suggest that a low level of coated ZnO might well substitute for a pharmacological level of native ZnO in dietary supplementation to alleviate colibacillosis of weaned piglets.

Effects of dietary energy level and slaughter weight on growth performance and grades and quality traits of the carcass in finishing pigs.

Man Jong Park*, Jin Yeun Jeong*, Duck Min Ha**, Jeong Cheol Han**, Tae Geon Sim**, Byung Chul Park***,Gu Boo Park*, Seon Tea Joo* and Chul Young Lee**Division of Animal Science, Gyeongsang National University*,Regional Animal Industry Center, Jinju National University**, CJ Corp.***ABSTRACT(Y×L)×D-crossbred gilts and barrows weighing 80.2±0.2kg were fed a “medium-energy”(ME) or “low-energy”(LE) diet(3.2 vs 3.0M cal DE/kg) and slaughtered at 110, 125, or 138kg, after which physicochemical and sensory quality traits of major primal cuts of resulting carcasses were analyzed, under a 2(sex)×2(diet)×3(slaughter weight; SW) factorial arrangement of treatments. The ADG and ADFI were greater(P<0.01) in barrows than in gilts and also in 125- and 138-kg vs 110-kg SW. Moreover, ADG and gain:feed were greater in ME vs LE(P<0.01), whereas ADFI was greater in LE vs ME(P<0.01). Backfat thickness, which increased with increasing SW(P<0.01), was not affected by sex or diet. Carcass marbling score was greater (P<0.01) in gilts and LE than in barrows and ME, respectively. Carcass quality grade, which was superior in LE vs ME, was not affected by SW, whereas the yield grade decreased abruptly between 125- and 138-kg SW primarily due to the upper limit of carcass weight imposed on the A and B grades. Physicochemical characteristics including pH, drip loss, and variables pertaining to color of belly, ham, and loin were not affected significantly by any of the treatment factors, albeit statistically significant in some cases, in terms of quality criteria. In sensory evaluation, the acceptability of fresh belly was not influenced by any of the treatment factors. Marbling score of fresh ham was greater in LE vs ME(P<0.01) and tended to increase between 110- and 125-kg SW(P=0.10); in loin, the increase of this variable between the two SW was significant(P<0.01). Following cooking, LE was superior to ME in the acceptability in belly and ham, but the effect of SW was insignificant in any of the sensory quality traits evaluated in this study in any of the three major primal cuts. In conclusion, the present results suggest that SW can be increased to up to 138 kg without compromising carcass quality and that LE has some beneficial effects on quality of the whole carcass and the major primal cuts. (Key words :Finishing pig, Slaughter weight, Diet, Carcass, Meat quality)

Relationships of the Slaughter Weight to Growth Performance and Meat Quality Traits in Finishing Pigs Fed A Low-energy Diet

Man Jong Park*, Jin Yeun Jeong*, Duck Min Ha**, Jae Wan Park**, Tae Geon Sim**, Han Sul Yang*,Chul Young Lee**, Seon Tea Joo* and Byung Chul Park***Division of Animal Science, Gyeongsang National University*, Regional Animal Industry Center, Jinju National University**, CJ Corp.***ABSTRACTThe present study was undertaken to investigate the effects of slaughter weight(SW) of finishing pigs fed a low-energy diet on growth efficiency and carcass quality and thereby to assess the optimal SW.(Yorkshire×Landrace)×Duroc-crossbred gilts and barrows were fed a diet containing 3,060kcal DE/kg from 80-kg BW and slaughtered at 110, 125, or 135kg, after which the belly, the most preferred cut in Korea, as well as the least preferred cuts ham and loin were subjected to physicochemical and sensory analyses. Both ADG and ADFI were greater(P<0.05) in the group slaughtered at 125 or 135 kg than in the 110-kg-SW group, whereas the opposite was true for gain:feed(P<0.01). Backfat thickness(BFT), which increased with increasing SW(P<0.01 and P<0.05), was greater in barrows than in gilts(P<0.01); BFT of barrows at 125kg(24.6 mm) was comparable to that of gilts at 135 kg (24.2 mm). Physicochemical characteristics of the belly, ham and loin were minimally affected, if not affected, by SW; of note, however, the redness of the ham increased between 110- and 125-kg SW(P<0.05). In sensory evaluation of the belly, the fat:lean balance, which is a most important quality trait in this cut, was best(P<0.05) at 125 kg of SW, but the overall acceptability of this cut was not changed by SW. In the ham and loin, the marbling score increased(P<0.01) between 110- and 125-kg SW, whereas color, aroma, off-flavor, and drip were unaffected by SW. In addition, the acceptability of the loin increased (P<0.05) between 110- and 125-kg SW. In cooked meats, none of color, aroma, off-flavor, juiciness, tenderness, taste, and acceptability was changed by SW, except for an increase(P<0.05) in darkness of loin color between 110- and 125-kg SW. In conclusion, the optimal SW for the present subpopulation on the present low-energy diet lie in between 125 and 135 kg for gilts and at 125 kg for barrows. (Key words :Finishing pig, Slaughter weight, Growth, Carcass, Meat quality)

Effects of dietary supplementation of lipid-coated zinc oxide on intestinal mucosal morphology and expression of the genes associated with growth and immune function in weanling pigs

Objective The present study was conducted to investigate the effects of a lipid-coated zinc oxide (ZnO) supplement Shield Zn (SZ) at the sub-pharmacological concentration on intestinal morphology and gene expression in weanling pigs, with an aim to gain insights into the mechanism of actions for SZ. Methods Forty 22-day-old weanling pigs were fed a nursery diet supplemented with 100 or 2,500 mg Zn/kg with uncoated ZnO (negative control [NC] or positive control [PC], respectively), 100, 200, or 400 mg Zn/kg with SZ for 14 days and their intestinal tissues were taken for histological and molecular biological examinations. The villus height (VH) and crypt depth (CD) of the intestinal mucosa were measured microscopically following preparation of the tissue specimen; expression of the genes associated with growth and immune function was determined using the real-time quantitative polymerase chain reaction. Results There was no difference in daily gain, gain:feed, and diarrhea score between the SZ group and either of NC and PC. The VH and VH:CD ratio were less for the SZ group vs NC in the jejunum and duodenum, respectively (p<0.05). The jejunal mucosal mRNA levels of insulin-like growth factor (IGF-I) and interleukin (IL)-10 regressed and tended to regress (p = 0.053) on the SZ concentration with a positive coefficient, respectively, whereas the IL-6 mRNA level regressed on the SZ concentration with a negative coefficient. The mRNA levels of IGF-I, zonula occludens protein-1, tumor necrosis factor-α, IL-6, and IL-10 did not differ between the SZ group and either of NC and PC; the occludin and transforming growth factor-β1 mRNA levels were lower for the SZ group than for PC. Conclusion The present results are interpreted to suggest that dietary ZnO provided by SZ may play a role in intestinal mucosal growth and immune function by modulating the expression of IGF-I, IL-6, and IL-10 genes.

Effects of milk replacer and starter diet provided as creep feed for suckling pigs on pre‐ and post‐weaning growth

This study was aimed at investigating the long-term effects of provision of liquid milk replacer (MR) and solid starter diet (SD) during lactation on post-weaning (PW) growth of pigs. In experiment 1, 33 cross-bred litters were allotted to four treatments: no supplement (CON), MR ad libitum, SD ad libitum and 100 g SD/litter/day from lactation day 4 through weaning at day 21 during late fall. In experiment 2, 40 litters received MR or none in July. PW pigs received commercial diets to marketing. In experiment 1, weaning weight (WW), pre-weaning average daily gain (ADG) and mortality (2.4%) were not influenced by creep-feeding MR or SD. ADG was greater (P < 0.05) in the MR group versus CON during days 21-54, but did not differ across the treatments during days 54-162. In experiment 2, ADG during lactation and WW were greater in the MR group versus CON, with mortality lower in the former (5.6 vs. 10.3%). However, PW ADG to day 175 did not differ between the two groups. Results suggest that creep-feeding MR or SD has no effect on PW growth. However, it remains possible that MR reduces PW mortality during the hot season.

Effects of dietary lipid-coated zinc on the antioxidant defense system in the small intestine and liver of piglets

The purpose of the study was to investigate the effects of lipid-coated ZnO (LCZ) and the level of LCZ compared with ordinary zinc oxide (ZnO) on antioxidant defense system in the intestine and liver of piglets. A total of forty piglets (n=8) were fed a diet supplemented with 100 ppm Zn with ZnO (ZnO-1), 2,500 ppm Zn with ZnO (ZnO-2), 100 ppm Zn as LCZ (LCZ-1), 200 ppm Zn as LCZ (LCZ-2), or 400 ppm Zn as LCZ (LCZ-3) for 14-d, respectively. The LCZ-3 group resulted in higher (P<0.05) mRNA expressions and activities of CuZn-superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT), and glutathione S-transferase (GST) in jejunal mucosa compared with the ZnO-1 and LCZ-1 groups, while no difference was observed in the mRNA level of antioxidant genes between the ZnO-1 and ZnO-2 groups. Within the LCZ groups, the LCZ level linearly and quadratically (P<0.01) increased antioxidant enzymes in the jejunum. The maximum response of jejunal antioxidant enzymes to Zn supplementation was achieved by 400 ppm of LCZ. Hepatic mRNA expression of antioxidant enzymes was unaffected by Zn source and level, while hepatic SOD and GST activities were greater (P<0.05) in the LCZ-3 group than in the ZnO-1 group. No difference was observed in lipid peroxidation of the jejunum and liver and the total antioxidant power of plasma among groups. In conclusion, a supplementation with 400 ppm of LCZ resulted in a maximum increase in antioxidant enzymes, indicating that LCZ may affect antioxidant defense system more profoundly than ZnO.

Correction to: effects of dietary supplementation of a lipid-coated zinc oxide product on the fecal consistency, growth, and morphology of the intestinal mucosa of weanling pigs

Due to a technical issue this article [1] was accidentally published in volume 59, the correct volume for this article is volume 60.