C. Young Lee

Intestinal Growth and Development of Weanling Pigs in Response to Dietary Supplementation of Antibiotics, Phytogenic Products and Brewer's Yeast plus Bacillus Spores

A total of 96 crossbred weanling barrows aged 21 days were randomly allocated to 32 pens of a new nursery to investigate the effects of antibiotics, phytogenics, and probiotics on intestinal growth and development. The animals were fed a set of three-phase basal diets containing 0.3% zinc oxide (CON) or the basal diets supplemented with 353 ppm of a combination of tiamulin, neomycin, chlortetracycline, and oxytetracycline (ANTI), 75 ppm triterpenoid saponin plus 150 ppm mixed saccharides (HERB; Sacchapin ® ), or 1 × 10 7 brewers yeasts plus 8 × 10 7 spores of each of Bacillus licheniformis and Bacillus subtilis per kilogram feed (PROBIO; Yeasture Plus 2B ® ) for five weeks. Thirty-two pigs representing as many pens were slaughtered at the end of the feeding trial, after which morphological measures and digestive enzyme activities of intestinal mucosa were determined. Weight gain and gain:feed of the pigs were not affected by the dietary treatments (TRT) during the overall feeding trial. Total intestinal length was greater in PROBIO than in ANTI (P<0.05). Wet mucosa weight of the duodenum was not affected by TRT. However, jejunal mucosa weight was greater in PROBIO than in any other group sum of mucosa weights of the duodenum and jejunum was greater (P<0.05) in PROBIO than in ANTI and HERB. The height and width of duodenal villus were not affected by TRT, but crypt depth decreased (P<0.05) in response to HERB and PROBIO vs CON. Specific activities of alkaline phosphatase, sucrase, maltase, lactase, and leucine aminopeptidase in the duodenum and jejunum were not changed by TRT. In conclusion, results suggest that the present dietary treatments have no effects on growth performance of weanling pigs and that of PROBIO enhances intestinal growth and development under a clean experimental setting. (Key words : Weanling pig, Antibiotic, Herb extract, Probiotic, Intestine)

Effects of Dietary Energy Level on Growth Efficiency and Carcass Quality Traits of Finishing Pigs

ABSTRACT A total of 96 non-lean-type (Yorkshire ×Landrace) × Duroc gilts and barrows weighing approximately 80 kg were randomly allocated to 24 pens under a 2 (sex) × 3 [diet; 3.4, 3.2, and 3.0 Mcal DE/kg {‘high’-, ‘medium’-, and ‘low’-energy diets (HE, ME, and LE), respectively}] factorial arrangement of treatments. All animals were slaughtered approximately at 115 kg, after which carcass quality traits and grades and physicochemical and sensory characteristics of the loin related to meat quality were analyzed. The ADG and gain:feed were not affected by the sex or dietary treatment, whereas ADFI was greater in the ME vs HE group. Backfat thickness was greater in barrows vs gilts and also in ME and HE vs LE only in barrows. Enumerated carcass marbling and quality grade, which were highly correlated (r=0.56; P<0.01), were greater in barrows vs gilts. Physicochemical characteristics including the color, pH, drip loss and contents of moisture, protein, and fat of fresh loin, as well as sensory characteristics of fresh and cooked loin, were not affected by the sex or dietary treatment, except for shear force for cooked loin which was greater (P<0.05) in LE and ME vs HE. In conclusion, it is thought that ME is comparable to HE in terms of the effect on growth and carcass quality of finishing pigs, but that the relative effect of LE vs ME needs to be further studied. (

Feasibility of Increasing the Slaughter Weight of Finishing Pigs

The present review was aimed to assess the feasibility of increasing the slaughter weight (SW) of finishing pigs. Growth performance, including ADG, ADFI and gain:feed, does not change significantly with increasing SW between 110 and 135±5 kg in lean-genotype pigs, whereas in non-lean pigs, ADG and gain:feed decrease with increasing SW within the similar range of BW. Backfat thickness (BFT) and marbling of the carcass, which are greater in barrows than in gilts, increase with the increase of SW. The SW could be increased by using a low-energy diet and thereby reducing the rate of fat deposition per weight gain. The yield of the belly increases with the increase of SW, which may be economically significant in Korea. However, yields of some other primal cuts do not change so much as to affect the carcass value. The redness and fat content of the muscle increase slightly with the increase of SW whereas moisture content is minimally influenced by SW. Muscular protein content rarely changes, but sometimes increases slightly, with increasing SW. Other physicochemical characteristics, including lightness, pH, drip loss, and cooking loss of the muscle, are barely influenced by SW. Marbling of fresh loin and ham increases with increasing SW. Sensory characteristics of fresh loin, ham, and belly, including color, aroma, off-flavor, drip, and acceptability, are not influenced significantly by SW. The eating quality of cooked pork also has almost no relation to SW. In conclusion, it is thought that the current SW for moderately lean barrows and gilts can be raised up to 125 and 135 kg, respectively, with BFT at these weights predicted to be approximately 24 mm near the last rib, without compromising the meat quality. (Key words : Finishing pig, Growth, Slaughter weight, Carcass, Meat quality)

Effects of the Decreased Carcass Grade of Finishing Pigs due to Increasing Market Weight on Carcass Quality Traits and Physicochemical and Sensory Quality Characteristics of the Loin and Belly

본 연구는 과중량으로 인해 강등된 도체등급이 등심과 삼겹살의 육질 특성에 미치는 영향을 조사하기 위해 수행되었다. 85~150kg 범위의 500두 출하돈의 도체로부터 평균 크기의 1+A 등급 도체 7개, A 등급 도체의 상한중량(95kg)에 근접한 1A 등급 도체 7개, B 등급 도체의 상한중량(99kg)에 근접한 1B 등급 도체 12개 및 100kg 이상의 2C 등급도체 각각 12개를 본 연구의 공시도체로 선발하였다. 근내지방도는 1+A 등급 도체가 다른 세 등급 도체보다 높았지만 근육과 지방의 색깔 및 조직감 관련 특성은 네 개의 도체등급간 차이가 없었다. 등심의 색깔, pH, 화학적 조성 및 조직 감 관련 품질 특성은 도체등급 저하로 인해 단지 최소 수준만 변하였다. 등심 및 삼겹살 신선육에 대한 관능검사에서 이취는 도체등급의 영항을 받지 않았고, 수분삼출도는 1+A 등급 도체가 가장 낮았으며, 색깔과 근내지방도는 도체등급의 영향을 받지 않거나 최소한의 영향을 받았다. 그러나 이들 부위 신선육의 기호도는 도체등급간 차이가 없었다. 등심과 삼겹살 가열육에서는 맛과 기호도가 비록 구배는 낮았지만 도체등급이 저하될수록 저하되는 경향을 보였고 적어도 1+A와 2C 등급간에는 유의적인 차이가 있었다. 결론 적으로 과중량으로 인해 등급이 저하된 돼지 도체는 육질 또한 약간 저한되었는데 이는 즉 돼지 도체의 규격등급이 어느 정도는 육질도 반영합을 시사한다.

Relationships of Muscle Fiber Characteristics to Dietary Energy Density, Slaughter Weight, and Muscle Quality Traits in Finishing Pigs

The present study was conducted to investigate the relationships of muscle fiber characteristics to dietary energy density (3.0 (Low-E) vs. 3.2 (Med-E) Mcal DE/kg)) and slaughter weight (SW; 110, 125, and 138 kg) in finishing pigs (gilt vs. barrow) using a 2×3×2 factorial treatment design. Forty-one longissimus dorsi muscle (LM) samples were analyzed histochemically, with growth performance and physicochemical data for the 41 animals and their LM out of 192 animals and 72 LM used in a previous study retrospectively included. The ADG was less (P<0.01) in the Low-E than in the Med-E group (0.93 vs. 0.73 kg) whereas lightness (L*) and redness (a*) of LM were greater in the Low-E group SW did not influence these variables. The diameter and perimeter of the type I (slow-oxidative), type IIA (fast oxido-glycolytic) and type IIB (fast glycolytic) fibers increased with increasing SW whereas densities of the fibers decreased. However, the number and area percentages of the fiber types were not influenced by SW or dietary energy density. The percentage and per-mm 2 density of type IIB fibers were negatively correlated with SW (r =-0.33 and -0.57, with P<0.05 and <0.01, respectively), whereas type I fiber number percentage was positively correlated with SW (r = 0.31; P<0.05). Marbling score was negatively correlated (P<0.05) with type I (r =-0.36) and type IIB (r =-0.39) fiber densities. The a* was correlated (P<0.01) with both type I and type IIB fiber number percentages in the opposite way (r = 0.42 and -0.47, respectively). However, L* (lightness), drip loss and pH24h were not correlated with the fiber number percentage or density of any fiber type. Collectively, results indicate that muscle fibers grow by hypertrophy during the late finishing period, but that fiber characteristics other than the size are not significantly influenced by dietary energy density or SW.

Effects of varying nursery phase-feeding programs on growth performance of pigs during the nursery and subsequent grow-finish phases

The present study investigated the effects of varying durations of nursery diets differing in percentages of milk products on growth performance of pigs during the nursery phase (NP) and subsequent grow-finish phase (GFP) to find the feasibility of reducing the use of nursery diets containing costly milk products. A total of 204 21-d-old weanling female and castrated male pigs were subjected to one of three nursery phase feeding programs differing in durations on the NP 1 and 2 and GFP diets containing 20%, 7%, and 0% lacrosse and 35%, 8%, and 0% dried whey, respectively, in 6 pens (experimental units) for 33 d: HIGH (NP 1, 2 and 3 diets for 7, 14, and 12 d), MEDIUM (NP 2 and 3 for 14 and 19 d), and LOW (NP 2 and 3 and GFP 1 for 7, 14, and 12 d). Subsequently, 84 randomly selected pigs [14 pigs (replicates)/pen] were fed the GFP 1, 2 and 3 diets during d 54-96, 96-135, and 135-182 of age, respectively. The final body weight (BW) and average daily gain (ADG) of nursery pigs did not differ among the HIGH, MEDIUM, and LOW groups (14.8, 13.3, and 13.7 kg in BW and 273, 225, and 237 g in ADG, respectively). The average daily feed intake during the nursery phase was greater (p <0.01) in the HIGH group than in the MEDIUM and LOW groups, whereas the gain:feed ratio did not differ across the treatments. The BW on d 182 and ADG during d 54-182 were greater in the HIGH and MEDIUM groups vs. the LOW group (110.0, 107.6, and 99.6 kg in BW, respectively; p <0.01). The backfat thickness and carcass grade at slaughter on d 183 did not differ across the treatments. In conclusion, the MEDIUM program may be inferior to the commonly used HIGH program in supporting nursery pig growth. Nevertheless, the former appears to be more efficient than the latter in production cost per market pig whereas the LOW program is thought to be inefficient because of its negative effect on post-nursery pig growth.

Effects of the Low-Crude Protein and Lysine (Low CP/lys) Diet and a Yeast Culture Supplemented to the Low CP/lys Diet on Growth and Carcass Characteristics in Growing-finishing Pigs

The present study was performed to investigate long-term effects of the low-crude protein and lysine (low CP/lys) diet and a yeast culture supplemented to the low CP/lys diet on growth and carcass characteristics in growing-finishing pigs. Forty-five gilts and 45 barrows weighing approximately 25 kg born to Yorkshire Landrace dams and Duroc sires were allocated to nine pens, with five gilts and five barrows assigned per pen. Every three pens received CP/lys-rich grower and finisher diets (control), low CP/lys grower and finisher (basal), or the low CP/lys grower and finisher supplemented (2%) with a yeast culture providing Saccharomyces cerevisiae cells/kg diet (yeast) for 31 and 79 days, respectively. The ADG was less in the low CP/lys (basal + yeast) group than in the control group (P-quality grade carcasses in the former compared with that for the latter. Supplementation of the yeast culture to the basal diet caused a decrease in ADG during the grower phase (P-quality grade carcasses. In conclusion, results indicate that long-term provision of the low CP/lys diet has a beneficial effect on marbling and carcass quality grade as well as a negative effect on weight gain and that the yeast culture supplemented to the low CP/lys diet has no beneficial effect on weight gain or carcass quality.

Effects of the lipid-coated zinc oxide dietary supplement on intestinal mucosal morphology and gene expression associated with the gut health in weanling pigs challenged with enterotoxigenic Escherichia coli K88

Abstract: Effects of a lipid-coated zinc oxide (ZnO) Shield Zn® (SZ) vs. ZnO were evaluated. Forty 25-d-old weanling pigs were fed a nursery diet supplemented with 100 mg kg-1 Zn with ZnO (ZnO-100), ZnO-2500, SZ-100, -200, or -400. All piglets were challenged orally with 5 × 108 colony-forming units of enterotoxigenic Escherichia coli K88 on day 7 and euthanized on day 14. The fecal consistency score (FCS) was less for the SZ group vs. ZnO-100 (P < 0.05). The intestinal villus height:crypt depth ratio and goblet cell density were greater for the SZ group vs. ZnO-100. By regression analyses, SZ-100 to -200 and SZ-300 to -400 were comparable to ZnO-2500 in the FCS and intestinal variables, respectively. The jejunal mucosal mRNA level did not differ between the SZ group and either ZnO group in insulin-like growth factor-I and multiple structural proteins and cytokines including zonula occludens protein (ZO) 1 and interleukin (IL) 10 except for lower ZO-1 and IL-10 mRNA levels for the SZ group than for ZnO-2500 and ZnO-100, respectively. The ZO-1 mRNA level regressed positively on the supplemental SZ concentration. Results suggest that SZ play a role in epithelial barrier function and inflammation by modulating the expression of ZO-1 and IL-10.

Relationships between Pork Quality Traits and Growth Factor Concentrations in Serum and Longissimus dorsi Muscle before and at Slaughter in Female Market Pigs

The present study was conducted to test a hypothesis that pork quality traits would be influenced by the systemic and/or local bioavailability of insulin-like growth factor-I (IGF-I), transforming growth factor-β 1( TGF-β1), or epidermal growth factor (EGF) before or at slaughter. To this end, 60 cross-bred female market pigs weighing approximately 110 kg were slaughtered, after which Longissimus dorsi muscle (LM) samples taken at slaughter (D 0) and blood samples taken at D -7 and D 0 were analyzed. The 60 carcasses rendered 36 RFN (reddish-pink, firm, and non-exudative), 16 RSE (reddish-pink, soft, and exudative), and 6 PSE (pale, soft, and exudative); 2 DFD (dark, firm, and dry) also were found but were excluded in subsequent experiments. The L* and drip loss were greater in PSE vs. RFN and RSE and in PSE and RSE vs. RFN, respectively, as they should (P<0.05). The pH45min was less in PSE vs. RFN (P<0.05); pH24h tended to be less in the former (P=0.09). The LM IGF-I and TGF-β1 as well as serum EGF concentrations were less in PSE than in RFN. None of the other LM and serum concentrations of the three growth factors differed across the three pork quality categories. The LM IGF-I and TGF-β1 concentrations and serum EGF concentration at D 0 were negatively correlated with drip loss (r =-0.36(P<0.01), -0.44 (P<0.01), and -0.32 (P<0.05), respectively). However, none of the serum and LM growth factor variables was correlated with L* or a* (redness) of LM. Taken together, results suggest that locally expressed IGF-I and TGF-β1 and blood-borne EGF may have a beneficial effect on postmortem water holding capacity of the muscle and that pork quality traits could be predicted to some extent from concentrations of IGF-I and TGF-β1 in muscle and EGF in serum at slaughter.

Effects of Extruded and Extruded-Pelleted Corn Products Partially Substituted for Unprocessed Corn of the Starter Diet on Growth Performance and Incidence of Diarrhea in Weanling Pigs

ABSTRACT The aim of the present study was to investigate the effects of partial substitution of an extruded or extruded-pelleted corn product for unprocessed corn of the starter diet on growth performance and incidence of diarrhea in weanling pigs. Seventy-two 21-day-old weanling pigs were allotted to 24 pens and provided ad libitum with one of the four experimental diets for 3 wk in two serial feeding trials during summer beginning from late June. The treatments were a milk product-soy-corn-based control diet containing 25% unprocessed corn and the other three diets only substituted with 12.5% extruded corn Suprex ® , Optigrain ® , an extruded mixture of wheat, rye and durum, or extruded-pelleted corn for an equal percentage of unprocessed corn of the control diet. All diets were supplemented with 100 ppm sulfathiazone, 50 ppm penicillin, and 100 ppm chlortetracycline for preventive medication. The initial and final weights as well as gain : feed were less in the second trial than in the first one (P<0.05). However, effects of the dietary treatments were not detected in any of the performance variables including final weight, ADG, ADFI, and gain : feed, nor were there any interactions between the trial and dietary treatment. In addition, almost all pigs exhibited normal firm feces in both trials and therefore there was no main effect in the fecal consistency score. Results suggest that partial substitution of the thermally processed corn for unprocessed corn of the milk product-corn-soy-based and medicated starter diet has no effect on growth performance or incidence of diarrhea in weanling pigs.(