The present study was conducted to investigate the effect of environmental temperature and backfat thickness (BT) on the reproductive performance of lactating sows. Sixty crossbred sows were allotted to four groups in a 2×2 factorial arrangement by environmental temperature (high temperature [HT], 27.5±1.76℃; low temperature [LT], 23.3±0.89℃) and BT (<20 mm, average 17.70 mm; ≥20 mm, average 23.20 mm) from July to August 2019. Sows in the HT group experienced a greater change in BT and a lower feed intake. Losses in body weight and BT were lower in sows with <20 mm BT than in those with ≥20 mm BT. Sows with low BT had a lower weaning-to-estrus interval than sows with high BT (5.20, 4.93 d vs. 5.87, 5.60 d, respectively). Piglet survivability was lower in the HT group (90.31%) than in the LT group (94.87%). Piglet weaning weight and average daily weight gain were greater in sows with <20 mm BT (5.75 kg and 201.46 g, respectively) than in those with ≥20 mm BT (5.49 kg and 188.41 g, respectively). Sows in the HT group had higher cortisol concentrations than those in the LT group (post-farrowing: HT 7.86 μg/mL vs. LT 6.04 μg/mL; weanling: HT 5.48 μg/mL vs. LT 4.40 μg/mL). In conclusion, environmental temperature adversely influenced sow performance and cortisol levels. Moreover, sows with low BT had a greater weaning-to-estrus interval when subjected to heat stress.

The objective of this experiment was to determine the effect of supplementation of hot melt extrusion (HME) processed Zn sulfate on growth performance, nutrients digestibility, small intestinal morphology and excretion of Zn in weanling pigs. A total of 200 piglets of mixed sex randomly allotted to four treatments on the basis of initial BW (7.15±0.81 kg). There were five replicates in each treatment with 10 pigs per replicate. The experimental treatments consisted of: 1) basal diet containing ZnSO4; 2) basal diet containing Zn-Methionine (ZnMet); 3) basal diet containing low level of nano-Zn as HME (ZnHME50); 4) basal diet containing medium level of nano-Zn as HME ZnSO4 (Zn-HME75). The average daily gain was improved by the ZnMet and ZnHME75 compared with the pigs fed ZnSO4 supplemented diets (p=0.009). Moreover, ZnHME75 and ZnMet affected on the ATTD of CP during phase 2 (p=0.014). The villus height (VH) was affected by increasing when pigs fed diets supplemented the ZnHME75 (P=0.044). The pigs fed diets supplemented ZnHME50 had significantly the lowest (p=0.037) Zn content in liver compared with other treatments. The Zn content in the feces was significantly higher (p<0.001) in ZnSO4 and ZnMet compared with ZnHME50 or ZnHME75. In conclusion, it could be concluded that dietary Zn can be reduced by 25% with ZnHME without any detrimental effect on performance of weanling pigs.

The present study was conducted to determine the optimal supplementation level of beta-mannanase in the diet of laying hens. A total of 320 Hy-Line Brown layers (80 weeks of age) were assigned randomly into four groups on the basis of laying performance. Each treatment had eight replicates with 10 birds each (80 birds per treatment). Two hens were caged individually. Treatments were basal diet supplemented with 0 (control), 0.04, 0.08, and 0.16% beta-mannanase during the nine-week feeding period. Laying hens fed diets supplemented with increasing levels of beta-mannanase had increased (linear, p<0.05) overall egg production and egg mass. In addition, these hens had greater retention of dry matter, crude protein, gross energy, calcium, and mannan (linear, p<0.05). Dietary beta-mannanase treatments had no effect on blood metabolites such as total carbohydrate, triglycerides, glucose, total protein, and blood urea nitrogen, or excreted ammonia nitrogen and volatile fatty acids. The results obtained in present study indicate that dietary supplementation of beta-mannanase has the potential for improving the performance of laying hens. The optimal supplementation level is 0.04% beta-mannanase in the diet.

The present study was conducted to investigate the effects on growth performance, nutrient digestibility, and gut health of broiler chickens when a dietary supplementation of multienzymes was added to diets, containing different energy levels. A total of 480 broiler chickens of similar body weight (Ross 308, 1-day-old) were randomly subjected to four treatments. The dietary treatments included a corn-soybean meal-based diet supplemented with: multienzyme (amylase+protease+ mannanase+xylanase+phytase), 0.05% enzyme, and different energy levels (3010 and 3060 kcal/kg). The experimental diets were fed to the chicks in a mash form for 35 days in two phases (1–21 d, phase I; and 22–35 d, phase II). During the overall period, chicks fed with diets supplemented with multienzymes had a better weight gain (p<0.05) and feed conversion ratio (FCR) than those fed with diets without enzymes. There was no difference in the growth rate and FCR among the chicks fed with diets supplemented with enzymes, even though the dietary energy levels were different. The apparent fecal and ileal digestibility of dry matter, gross, crude protein, calcium, and phosphorus were significantly enhanced (p<0.05). The population of cecal and ileal Lactobacillus spp. was significantly increased (p<0.05), and Clostridium spp. and coliforms were significantly decreased (p<0.05) in diets supplemented with enzymes. Villus height and villus height to crypt depth ratio in the small intestine was also significantly enhanced (p<0.05) in diets supplemented with enzymes. In conclusion, multienzyme supplementation had positive effects on the weight gain of broilers, FCR, digestibility of nutrients, and on the growth of intestinal microbiota.

The present study investigated the effects of fermented potato protein (FPP, Lianol® ferity) during gestation and lactation on productivity of sows. A total of 50 crossbred sows (Landrace×Yorkshire) in their 3 to 5 parities were allotted to one of two treatments (n=25) including control and FPP groups. FPP tablets applied in sows in two stages. Stage one involved applying FPP daily from 3 days before farrowing to 2 days after for 5 consecutive days. The second stage also involved a 5 day period around weaning time from 3 days before to 2 days after. After farrowing, the amount of feed offered 3 times per day gradually increased from about 3.6 kg at farrowing to 8.4 kg at late lactation. During the first lactation FPP tended to increase backfat thickness (BFT) at weaning at the first (p=0.069) whereas FPP increased BFT (p<0.05) at weaning in the second lactation. There was no significant effect of FPP on body weight changes and daily feed intake of sows. Decreased weaning to estrus interval was associated with applying lianol tablet at the second lactation (p<0.05). Weight of born alive piglets, weaned piglets and total weight gain were greater in FPP group at the second lactation (p<0.05). Applying FPP tended (p=0.062) to increase insulin like growth factor-Ⅰ(IGF-I) at the weaning time in the first lactation. The effect of FPP on IGF-I was significant at the second lactation, revealing a higher concentration in blood at post farrowing and weaning time (p<0.05). This study shows the benefit of using FPP tablets in sows to increase blood IGF-I and both initial and final litter size to improve piglet weaning weights.

A total of 240 growing pigs were distributed in three treatment groups to investigate the influence of fermentation in different feeder type on the growing finishing pigs. The treatments were dry feeding (DF), wet feeding (WF) with dry-wet feeders and liquid feeding (LF) with freshly prepared 3:1 water to feed ratio fed three times a day throughout the experiment. The average daily gain (ADG) and body weight were consistently greater (p<0.05) in LF than the others. When the entire experimental period was taken under consideration the ADG and body weight was also found to be increased (p<0.05) in WF in comparison to DF. The average daily feed intake (ADFI) and growth to feed ratio (G/F) was not affected however the average daily water intake (ADWI) and water to feed ratio (W/F) were significantly reduced (p<0.01) in WF in comparison to DF and LF. The ATTD of DM, GE and CP was increased (p<0.05) in WF and LF in comparison to DF at both phase I and II (4th and 8th wk) of the experiment. Carcass characteristics and blood parameters were not affected (p>0.05) in any of the feeding type in growing finishing pigs. It can be concluded that wet feeding with dry-wet feeders is good for enhancing the growth performance in the later stages while fresh liquid feeding in ratio 3:1 is beneficial for the growing finishing pigs throughout the experiment.

Two experiments were conducted to determine the effect of wood vinegar (WV) on the fecal microbes and gas emission in weaned pigs. In Exp. 1, 224 weaned piglets (L×Y×D, 21 d-old, initial BW 6.02 ± 0.52 kg) were assigned to four treatments of different WV levels in randomized completely block design with four replicates (14 piglets/pen) for 28 days, including phases I (0-2 wk) and phase II (3-4 wk). The dietary treatments were 0, 0.1, 0.2 and 0.3% of WV added to a corn-soybean meal basal diet. The concentration of ammonia measured at 0 h and 24 h in feces did not differ among dietary treatments (p>0.05), but it was linearly decreased (p<0.05) in 0.2% and 0.3% addition level measured at 48 h and 72 h. The concentration of hydrogen sulfide had no significant change (p>0.05) within treatments measured at different time. The fecal total bacteria (TBC), Lactobacilli(LAB) and E. coli were measured on 14 d and 28 d. TBC were higher (p>0.05) in WV added treatments than the control. Similar results were obtained for LAB. But E. coli populations were decreased (p<0.05) in treatments added WV compared to control measured on 14 d and 35 d. In Exp. 2, 288 weaned piglets (L×Y×D, 21 d-old, initial BW 6.62 ± 0.31 kg) were assigned to four treatments in a randomized completely block design with four replicates (18 piglets/pen) for 28 days. The dietary treatments were basal diet (negative control, NC), 0.2% organic acid (positive control, PC), 0.2% antibiotic (AT) and 0.2% WV added to a corn-soybean meal basal diet. The fecal total bacteria (TBC), Lactobacilli(LAB) and E. coli were measured on 14 d and 28 d. TBC, LAB and E. coli showed lower counts in pigs fed AT diets than others. In conclusion, these results indicated that wood vinegar could reduce the NH3 concentration of feces and inhibited the growth of harmful bacteria.

This study was carried out to investigate the effect of market weight on the sensory attributes of Korean native black pork. The M. longissimus from Korean native black pigs (KNP) with market weight of 56 kg and 70 kg were utilized as experimental materials. The intramuscular fat content, a* (redness) and b* yellowness) values were higher in KNP with market weight of 70 kg than in KNP with market weight of 56 kg (p<0.05). In TPA, hardness, adhesiveness, guminess and chewiness were lower in KNP with market weight of 70 kg than in KNP with market weight of 56 kg (p<0.05). The marbling score, meat color and overall liking among sensory evaluation of raw pork and taste, texture and overall liking among sensory evaluation of cooked pork were higher in KNP with market weight of 70 kg than in KNP with market weight of 56 kg (p<0.05). Therefore, higher market weight of KNP increased the sensory attributes of pork.

This study was carried out to investigate the comparison of meat quality of Korean native black porks and modern genotype pork fed high and low lysine levels of diets at growing and finishing stages during refrigerated storage after thawing. M. longissimus from Korean native black pigs (gilts) with a live weight of 65 kg and modern genotype pork (gilts) with a live weight of 110 kg were frozen at -80 ℃ for 1 month and placed in the dark room at 1℃ for 7 days after thawing. The moisture content was significantly lower in modern genotype pork fed high lysine level of diets than to the other treatments (p<0.05), but crude fat content was significantly higher in modern genotype pork fed high lysine level of diets (p<0.05). The pH value and sensory evaluation were significantly higher in Korean native black pork than to modern genotype pork (p<0.05), and the drip loss was significantly lower in Korean native black pork (p<0.05). CIE L*, ho and hunter L were significantly lower in modern genotype pork fed high lysine level of diets than to modern genotype pork fed low lysine level of diets (p<0.05). Myristate, palmitate and saturated fatty acid content were significantly lower in Korean native black pork fed high lysine level of diets than to Korean native black pork fed low lysine level of diet (p<0.05), but unsaturated fatty acid content and UFA/SFA ratio were higher in Korean native black pork fed high lysine level of diets (p<0.05). Consequently, as Korean native black pigs were fed high lysine level of diets at growing and finishing stages, saturated fatty acid content of pork increased but unsaturated fatty acid content and UFA/SFA ratio of pork decreased. And the water-holding capacity, color stability and sensory evaluation of Korean native black porks were better than those of modern genotype pork.

This study was carried out to investigate the comparison of quality characteristics of Korean native black porks fed high, medium and low levels of lysine diets at growing and finishing stages during refrigerated storage. M. longissimus from Korean native black pigs (gilts) with a live weight of 65 kg were placed in the dark room at 4℃ for 7 days and utilized for the quality measurements. The proximate composition, drip loss, TBARS value and sensory evaluation of raw and cooked meat were not affected by dietary lysine level. Korean native black pork fed low lysine diets showed the highest redness (a*) at day 7. Consequently, as Korean native black pigs were fed low lysine diets at growing and finishing stages, it was effective in color stability of porks.

This study was conducted to determine the replacement effect of spray dried plasma protein (SDPP) with dried porcine solubles (DPS) in weaning pigs. An ileal digestibility trial, at first, was conducted to formulate the experimental diets with SDPP or DPS. Six piglets (21-d old and 6.12kg BW) with T -cannula in the terminal ileum were used. In a feeding trial, 180 pigs (21-d old and 5.98kg BW) were alloted in a completely randomized block design. Treatments were T1 (SDPP 5%, DPS 0%), T2 (SDPP 5%, DPS 2.5%), T3 (SDPP 2.5%, DPS 0%), and T4 (SDPP 2.5%, DPS 2.5%) for phase I, and T1 (SDPP 3%, DPS 0%), T2 (SDPP 3%, DPS 1.5%), T3 (SDPP 1.5%, DPS 0%), and T4 (SDPP 1.5%, DPS 1.5%) for phase Ⅱ. Phase Ⅰ(0～1 week) diet was formulated to contain 3,300ME kcal/kg and 1.25% digestible lysine, and phase Ⅱ (2～3 week) diet contained 3,320ME kcal/kg and 1.10% digestible lysine. Chemical pompositions of the protein sources were higher in SDPP than DPS: CP (81.60 vs. 56.01), lysine (5.95 vs. 3.36), and methionine (1.85 vs. 1.22). Apparent ileal digestibilities of arginine, isoleucine, leucine, lysine, methionine, threonine and phenylalanine were higher in DPS than SDPP (p<0.05). The apparent ileal digestibility of essential amino acids (average) was also higher in DPS than SDPP (p<0.05). There were no significant differences (p>0.05) in ADG and ADFI of piglets during phase Ⅰ (0～1 week) and Ⅱ (2～3 week) among treatments. However, during phase Ⅱ, T2 showed better FCR than T1 (p<0.05). During the overall period, there was no significant difference in growth performance among treatments. When DPS was partially replaced for SDPP, the diet cost was significantly reduced (p<0.05) in terms of cost/kg of body weight. In summary, the digestibility of DPS was exellent, and it would be concluded that DPS can be partially replaced in the young pigs' diet containing SDPP in order to reduce diet cost in weaning pigs.

This study was carried out to investigate the effect of feeding level of dietary lysine on the quality of Korean native black pork during cold storage (4℃). After 54 Korean native black pigs was fed by the high, medium, low lysine dietaries at 25 kg live weight, the M. longissimus from 6 carcasses (3 gilts, 3 barrows) slaughtered at 65 kg live weight stored at 4℃ for 7 days. The proximate composition, drip loss, cooking loss, sensory evaluation was affected by feeding level of dietary lysine. The pH value was significantly higher in high lysine treatment than in the other treatments until 5 days (p<0.05) and significantly lower in medium lysine treatment (p<0.05). The CIE L* value was significantly higher in gilts among high lysine treatment (p<0.05) and increased significantly in all treatments until 5 days (p<0.05). The CIE a*, b*, C* values were higher in low lysine treatment. The hardness, adhesiveness, springiness, cohesineness, guminess, chewiness were lower in low lysine treatment and those in 7 days were lower than in 0 day.

Background : Zinc (Zn) is one of dietary micronutrients and it is second highest trace element in the body. Over 95% of Zn is located in the cells, but its dominant storage site is absent in the body. Deficiency of Zn may result in anorexia, dysgeusia, dysosmia, skin rash, infection, alopecia, growth failure, and impaired wound healing. Therefore, adequate supplementation of Zn is very important to maintain normal physiological conditions. Methods and Results : Zinc sulfate monohydrate (ZnSO4)-loaded nanocomposites (NCs) were fabricated by using a hot-melt extruder (HME) system. Soluplus (SP) was adopted as an amphiphilic polymer matrix for HME processing. The micro-size of ZnSO4 dispersion was reduced to nano-size by HME processing with the use of SP. ZnSO4 could be homogeneously dispersed in SP through HME processing. ZnSO4/SP NCs with a 75 ㎚ mean diameter, a 0.1 polydispersity index, and a -1 mV zeta potential value were prepared. The physicochemical properties of ZnSO4/SP NCs and the existence of SP in ZnSO4/SP NCs were further investigated by solid-state studies. Nano-size range of ZnSO4/SP NC dispersion was maintained in the simulated gastrointestinal environments (pH 1.2 and 6.8 media). No severe toxicity in intestinal epithelium after oral administration of ZnSO4/SP NCs (at 100 ㎎/㎏ dose of ZnSO4, single dosing) was observed in rats. Conclusion : These results imply that developed ZnSO4/SP NC can be used as a promising nano-sized zinc supplement formulation. In addition, developed HME technology can be widely applied to fabricate nano formulations of inorganic materials.