• 제목/요약/키워드: intestinal crypt cell

검색결과 52건 처리시간 0.025초

제주산 참다래가 Loperamide로 유도된 변비에 미치는 영향 (Effects of the Actindia chinensis on Loperamide-induced Constipation in Rat)

  • 김동건;진영건;진주연;김상철;김성철;한창훈;이영재
    • 한국자원식물학회지
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    • 제24권1호
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    • pp.61-68
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    • 2011
  • 참다래 동결건조물을 2.5%, 5% 농도로 사료와 혼합하여 실험동물에 투여하고 실험 5일간 loperamide(2 mg/kg/day, s.c.)로 변비를 유도하여 참다래의 변비치료 및 예방 효과를 측정하였다. Lopermide를 단독 투여한 군은 정상대조군과 비교하여 변의 개수 및 중량이 유의적으로 감소하였으며 원위 결장 내 변 잔류의 증가 및 cecocolonic segment의 무게가 증가하였다. 참다래 동결건조물 및 loperamide를 투여한 군은 loperamide를 단독 투여한 군과 비교하여 변의 개수 및 중량이 유의적으로 증가하였으며 원위 결장 내 잔류 변 및 cecocolonic segment의 무게도 감소하였다. 이러한 결과는 참다래가 in vivo에서 변비 개선 효과가 있음을 보여준다. 변의 수분 함량에서도 loperamide로 변비를 유발시킨 군에서 감소하는 경향을 보였고 참다래 동결건조물 투여군에서 농도 의존적으로 증가하는 것을 확인 할 수 있었다. 조직학적 검사에서도 참다래 동결건조물 투여군의 원위 대장관에서 crypt cell내 점액의 증가와 장관내 분변의 점액질의 증가도 관찰되었다. In vitro 실험결과, 회장 적출 절편에서 참다래 동결건조물(2.5 mg/ml)을 전 처리 시 loperamide에 의한 장력과 진폭 억제가 부분적으로 차단되었으며 이러한 결과는 참다래 동결건조물의 변비 개선효과가 장의 운동성 촉진과 대장관 내 점액분비 증가에 의한 대장관 내용물의 이동성증가와 관련이 있음을 시사한다.

도적지유탕이 궤양성 대장염 유발 흰쥐에 미치는 영향 (A Study on the Treatment Effect of Dojeckjiyu-tang for Ulcerative Colitis)

  • 김승욱;임성우
    • 대한한의학회지
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    • 제23권3호
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    • pp.200-210
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    • 2002
  • Objectives: Dojeckjiyu-tang has been used to treat Hwaseol & Jeokri. The object of this study is examination of the treatment effect of Dojeckjiyu-tang for ulcerative colitis of the mouse descending colon. Methods and Materials : Twenty-one rats were divided into 3 groups and treated as follows: the control group was untreated mice. The UCE group was ulcerative colitis elicited mice. The DJT group was Dojeckjiyu-tang treated mice after ulcerative colitis elicitation. The groups were examined with common morphology, paneth cells in intestinal crypt, absorptive cells and goblet cells in epithelium, cell division in mucose, COX-1 as mucosal protector, COX-2 (which appears to play an important role in inflammation), IL-2R-, ICMA-1-inducing cellular immuno-chainreaction, and the distribution of apoptotic cells. Results: 1. The morphology of colonic mucosa from UCE mice: the disappearance of epithelium and intestinal propria in hemorrhagic erosions were seen, but in the morphology of colonic mucosa from DJT-treated mice, the configuration of epithelium and intestinal propria were the same as normal. 2. The distribution of goblet cells and absorptive cells with microvilli in intestinal propria from UCE mice: a noticeable decrease of goblet cells and absorptive cells with microvilli were seen, but with the distribution of goblet cells and absorptive cells with microvilli in intestinal propria from DJT -treated mice, the configuration of goblet cells and absorptive cells with microvilli were the same as normal. 3. The immunohistochemical stain for BrdD in colonic mucosa and COX-1 in lamina propria from UCE mice: BrdU positive cells and COX-1 positive cells in the region of hemorrhagic erosion disappeared, but in the immunohistochemical stain for BrdU in colonic mucosa and COX-1 in lamina propria from DIT-treated mice, BrdU positive cells and COX-1 positive cells were seen. 4. The immunohistochemical stain for COX-2 in lamina propria, IL-2R-in lamina propria, intestinal propria and submucosa and ICMA-1 in intestinal propria and submucosa from DCE mice: a noticeable increase COX-2, IL-2R-, ICMA-1 positive cells were seen, but in the immunohistochemical stain for COX-2 in lamina propria, IL-2R-in lamina propria, intestinal propria and submucosa and ICMA-1 in intestinal propria and submucosa from DJT-treated mice, a numerical decrease of COX-2, IL-2R-, ICMA-1 positive cells was observed. 5. The distribution of apoptotic cells in epithelium and lamina propria from UCE mice: a noticeable increase of apoptotic cells in region of hemorrhagic erosion was seen, but in the distribution of apoptotic cells in epithelium and lamina propria from DJT-treated mice, a remarkable decrease of apoptotic cells was seen. Conclusions: According to the above results, Dojeckjiyu-tang has a moderate effect on ulcerative colitis in descending colon.

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Expression of Cdc25B mRNA in Duodenal Mucosa of Chicken

  • Qin, Junhui;Zhang, Hui;Bao, Huijun;Zhou, Qiang;Liu, Yi;Xu, Chunsheng;Chu, Xiaohong;Chen, Qiusheng
    • Asian-Australasian Journal of Animal Sciences
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    • 제23권4호
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    • pp.530-536
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    • 2010
  • Cdc25B is a mitotic regulator that might act as a starter phosphatase to initiate the positive feedback loop at the entry into mitotic (M) phase. In the present study, distribution of Cdc25B mRNA in duodenal mucosa of the chicken was demonstrated by means of in situ hybridization histochemistry (ISHH) using sense and antisense digoxigenin (DIG)-labeled RNA probes. The results showed that there were many labeled cells distributing in the duodenal mucosa of the adult chicken. Of these labeled cells, 81.60${\pm}$9.63% of Cdc25B mRNA positive cells was distributed in the basilar part and mid-portion of the intestinal gland and 36.21${\pm}$8.81% in the middle and basilar portion of villi of the small intestine of the chicken, respectively. Most of these labeled cells were positive in the regions of the stem cell and proliferation. The signals of ISHH decreased from basilar to upper part in the crypt of Lieberkuhn and weakened in the inferior villi of the duodenum. Moreover, the positive signals were both in the cytoplasm and cell nucleus. However, the labeled cells were negative in both the lamina muscularis mucosae and muscular layer. The results of ISHH suggested the existence of Cdc25B mRNA and vigorous proliferation activities in the duodenal mucosa of adult chicken, replenishing the cells which had sloughed off from the superior part of the villus. Our results provide some molecular evidence for a regular pattern of avian intestinal epitheliosis and functional partition and provide an approach to further study of the locations of Cdc25B in the chicken.

Insulin-like growth factor가 소장 점막 세포 증식에 미치는 영향

  • 윤정한
    • 한국영양학회:학술대회논문집
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    • 한국영양학회 1995년도 추계학술대회 초록
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    • pp.11-34
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    • 1995
  • Growth hormone (GH) plays a key role in regulating postnatal growth and can stimulate growth of animals by acting directly on specific receptors on the plasma membrane of tissues or indirectly through stimulating insulin-like growth factor (IGF)-I synthesis and secretion by the liver and other tissues. IGF-I and IGF-Ⅱ are polypeptides with structural similarity with proinsulin that stimulate cell proliferation by endocrine, paracrine and autocrine mechanisms. The initial event in the metabolic action of IGFs on target cells appears to be their binding to specific receptors on the plasma membrane. Current evidence indicates that the mitogenic actions of both IGFs are mediated primarily by binding to the type I IGF receptors, and that IGF action is also mediated by interactions with IGF-binding proteins (IGFBPs). Six distinct IGFBPs have been identified that are characterized by cell-specific interaction, transcriptional and post-translational regulation by many different effectors, and the ability to either potentiate or inhibit IGF actions. Nutritional deficiencies can have their devastating consequence during growth. Although IGF-I is the major mediator of GH's action on somatic growth, nutritional status of an organism is a critical regulator of IGF-I and IGFBPs. Various nutrient deficiencies result in decreased serum IGF-I levels and altered IGFBP levels, but the blood levels of GH are generally unchanged or elevated in malnutrition. Effects of protein, energy, vitamin C and D, and zinc on serum IGF and IGFBP levels and tissue mRNA levels were reviewed in the text. Multiple factors are involved in the regulation of intestinal epithelial cell growth and differentiation. Among these factors the nutritional status of individuals is the most important. The intestinal epithelium is an important site for mitogenic action of the IGFs in vivo, with exogenous IGF-I stimulating mucosal hyperplasia. Therefore, the IGF system appears to provide and important mechanism linking nutrition and the proliferation of intestinal epithelial cells. In order to study the detailed mechanisms by which intestinal mucosa is regulated, we have utilized IEC-6 cells, an intestinal epithelial cell line and Caco-2 cells, a human colon adenocarcinoma cell line. Like intestinal crypt cells analyzed in vivo or freshly isolated intestinal epithelial cells, IEC-6 cells and Caco-2 cells possess abundant quatities of both type Ⅰ and type Ⅱ IGF receptors. Exogenous IGFs stimulate, whereas addition of IGFBP-2 inhibits IEC-6 cell proliferation. To investigate whether endogenously secreted IGFBP-2 inhibit proliferation, IEC-6 cells were transfected with a full-length rat IGFBP-2 cDNA anti-sense expression construct. IEC-6 cells transfected with anti-sense IGFBP-2 protein in medium. These cells grew at a rate faster than the control cells indicating that endogenous IGFBP-2 inhibits proliferation of IEC-6 cells, probably by sequestering IGFs. IEC-6 cells express many characteristics of enterocyte, but do not undergo differentiation. On the other hand, Caco-2 cells undergo a spontaneous enterocyte differentiation. On the other hand, Caco-2 cells undergo a spontaneous enterocyte differentiation after reaching confluency. We have demonstrated that Caco-2 cells produce IGF-Ⅱ, IGFBP-2, IGFBP-3, and an as yet unidentified 31,000 Mr IGFBP, and that both mRNA and peptide secretion of IGFBP-2 and IGFBP-3 increased, but IGFBP-4 mRNA and protein secretion decreased after the cells reached confluency. These changes occurred in parallel to and were coincident with differentiation of the cells, as measured by expression of sucrase-isomaltase. In addition, Caco-2 cell clones forced to overexpress IGFBP-4 by transfection with a rat IGFBP-4 cDNA construct exhibited a significantly slower growth rate under serum-free conditions and had increased expression of sucrase-isomaltase compared with vector control cells. These results indicate that IGFBP-4 inhibits proliferation and stimulates differentiation of Caco-2 cells, probably by inhibiting the mitogenic actions of IGFs.

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Effects of Single Cell Protein Replacing Fish Meal in Diet on Growth Performance, Nutrient Digestibility and Intestinal Morphology in Weaned Pigs

  • Zhang, H.Y.;Piao, X.S.;Li, P.;Yi, J.Q.;Zhang, Q.;Li, Q.Y.;Liu, J.D.;Wang, G.Q.
    • Asian-Australasian Journal of Animal Sciences
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    • 제26권9호
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    • pp.1320-1328
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    • 2013
  • Three experiments were conducted to evaluate the ME value, standardized ileal digestibility (SID) of amino acids (AA) of fish meal, and the effects of single cell protein (Prosin and Protide) replacing fish meal in diet on growth performance, nutrient digestibility and intestinal morphology in weaned piglets. In Exp. 1, twenty-four barrows with initial BW of $30.8{\times}2.6kg$ were allotted to one of four dietary treatments. Diet 1 contained corn as the only energy source. The other three diets replaced 20% of the corn in diet 1 with one of the three protein feeds (fish meal, Prosin and Protide), and the DE and ME contents were determined by difference. In Exp. 2, eight barrows (initial BW of $25.6{\pm}3.2kg$) were fitted with ileal T-cannulas and allotted to a replicated $4{\times}4$ Latin square design. Three cornstarch-based diets were formulated using each of the protein feeds as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. In Exp. 3, one hundred and eighty piglets (initial BW of $7.95{\pm}1.59kg$) weaned at $28{\times}2d$ were blocked by weight and assigned to one of five treatments for a 28-d growth performance study, each treatment was fed to six pens with six pigs (three barrows and three gilts) per pen. The five treatments consisted of the control group (CON), which was a corn-soybean meal diet containing 5% fish meal, and the other four treatments, which replaced a set amount of fish meal with either Prosin (2.5% or 5%) or Protide (2.5% or 5%). The diets were formulated to provide same nutrient levels. The results showed that on a DM basis, both of the DE and ME contents were lower in Prosin and Protide than that of fish meal (p<0.05). The SID of CP and all essential AA were greater in fish meal than in Prosin and Protide (p<0.05). The pigs fed CON diet had greater weight gain and lower feed conversion rate (FCR) than pigs fed 5% Prosin and 5% Protide diets (p<0.05). The digestibility of CP was greater in pigs fed CON, 2.5% Prosin and 2.5% Protide diets than the pigs fed 5% Prosin and 5% Protide diets (p<0.05). Villus height in jejunum and ileum, and villus height to crypt depth ratio in the jejunum were higher (p<0.05) in pigs fed CON, 2.5% Prosin and 2.5% Protide diets compared with the 5% Prosin and 5% Protide diets. Pigs fed CON diet had greater villus height to crypt depth ratio in the ileum than the pigs fed 5% Prosin and 5% Protide diets (p<0.05). In conclusion, although Prosin and Protide contained lower ME content and SID of AA than fish meal, Prosin and Protide replacing 50% of fish meal in diet with identical nutrient levels could obtain similar performance, nutrient digestibility and intestinal morphology in weaned pigs.

Lactobacillus casei Zhang Prevents Jejunal Epithelial Damage to Early-Weaned Piglets Induced by Escherichia coli K88 via Regulation of Intestinal Mucosal Integrity, Tight Junction Proteins and Immune Factor Expression

  • Wang, Yuying;Yan, Xue;Zhang, Weiwei;Liu, Yuanyuan;Han, Deping;Teng, Kedao;Ma, Yunfei
    • Journal of Microbiology and Biotechnology
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    • 제29권6호
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    • pp.863-876
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    • 2019
  • Farm animals such as piglets are often affected by environmental stress, which can disturb the gut ecosystem. Antibiotics were commonly used to prevent diarrhea in weaned piglets, but this was banned by the European Union due to the development of antibiotic resistance. However, the use of probiotics instead of antibiotics may reduce the risk posed by pathogenic microorganisms and reduce the incidence of gastrointestinal diseases. Therefore, this study was conducted to investigate the effects of Lactobacillus casei Zhang on the mechanical barrier and immune function of early-weaned piglets infected using Escherichia coli K88 based on histomorphology and immunology. Fourteen-day-old weaned piglets were divided into a control group and experimental groups that were fed L. casei Zhang and infected with E. coli K88 with or without prefeeding and/or postfeeding of L. casei Zhang. The L. casei Zhang dose used was $10^7CFU/g$ diet. Jejunum segments were obtained before histological, immunohistochemical, and western blot analyses were performed. In addition, the relative mRNA expression of toll receptors and cytokines was measured. Piglets fed L. casei Zhang showed significantly increased jejunum villus height, villus height-crypt depth ratio, muscle thickness, and expression of proliferating cell nuclear antigen and tight junction proteins ZO-1 and occludin. The use of L. casei Zhang effectively reduced intestinal inflammation after infection. We found that L. casei Zhang feeding prevented the jejunum damage induced by E. coli K88, suggesting that it may be a potential alternative to antibiotics for preventing diarrhea in early-weaned piglets.

Dietary Aloe Vera Gel Powder and Extract Inhibit Azoxymethane-induced Colorectal Aberrant Crypt Foci in Mice Fed a High-fat Diet

  • Chihara, Takeshi;Shimpo, Kan;Kaneko, Takaaki;Beppu, Hidehiko;Higashiguchi, Takashi;Sonoda, Shigeru;Tanaka, Miyuki;Yamada, Muneo;Abe, Fumiaki
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권2호
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    • pp.683-687
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    • 2015
  • Aloe vera gel exhibits protective effects against insulin resistance as well as lipid-lowering and anti-diabetic effects. The anti-diabetic compounds in this gel were identified as Aloe-sterols. Aloe vera gel extract (AVGE) containing Aloe-sterols has recently been produced using a new procedure. We previously reported that AVGE reduced large-sized intestinal polyps in Apc-deficient Min mice fed a high fat diet (HFD), suggesting that Aloe vera gel may protect against colorectal cancer. In the present study, we examined the effects of Aloe vera gel powder (AVGP) and AVGE on azoxymethane-induced colorectal preneoplastic aberrant crypt foci (ACF) in mice fed a HFD. Male C57BL/6J mice were given a normal diet (ND), HFD, HFD containing 0.5% carboxymethyl cellulose solution, which was used as a solvent for AVGE (HFDC), HFD containing 3% or 1% AVGP, and HFDC containing 0.0125% (H-) or 0.00375% (L-) AVGE. The number of ACF was significantly lower in mice given 3% AVGP and H-AVGE than in those given HFD or HFDC alone. Moreover, 3% AVGP, H-AVGE and L-AVGE significantly decreased the mean Ki-67 labeling index, assessed as a measure of cell proliferation in the colonic mucosa. In addition, hepatic phase II enzyme glutathione S-transferase mRNA levels were higher in the H-AVGE group than in the HFDC group. These results suggest that both AVGP and AVGE may have chemopreventive effects on colorectal carcinogenesis under the HFD condition. Furthermore, the concentration of Aloe-sterols was similar between 3% AVGP and H-AVGE, suggesting that Aloe-sterols were the main active ingredients in this experiment.

마우스에서 방사선 영향에 대한 녹차와 Diethyldithiocarbamate의 조절효과 (Modification of Gamma-radiation Response in Mice by Green Tea and Diethyldithiocarbamate)

  • 김세라;김성호;이해준;오헌;류시윤;이윤실;김태환;조성기
    • 한국식품영양과학회지
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    • 제32권7호
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    • pp.1108-1113
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    • 2003
  • 본 연구에서는 방사선 손상 경감효과를 나타내는 기호식품을 발굴하고자 국내에서 주로 음용되고 있는 녹차의 방사선 손상 경감효과를 확인하기 위하여 고선량 및 저선량 방사선을 마우스에 조사하고 소장움 생존, 내재성 비장 조혈세포집락 형성 및 apoptosis 유발 등을 관찰하였으며, 그 효과를 방사선 방호효과가 알려져 있는 diethyldithiocarbamate(DDC)와 비교$.$관찰하였다. 생존 소장움의 수는 방사선 조사 전 녹차 투여군(경구투여군 : p<0.01, 복강내 투여군 : p<0.01) 및 DDC 투여군(p<0.005)에서 유의성있게 증가되었다. 내재성 조혈세포집락 형성은 방사선 조사 대 조군에 비하여 조사 전 복강내 투여한 군(p<0.05)에서만 유의성 있는 증가를 나타냈으며, DDC 투여군에서는 효과를 관찰할 수 없었다. 방사선에 의한 apoptotic cell의 형성은 방사선 조사 전 녹차 투여군(경구 투여군 : p<0.005, 복강내 투여군 : p<0.05)및 DDC투여군 (p<0.005)에서 통계적으로 유의성 있게 감소되었다. 이상의 결과에서 녹차의 방사선 손상 경감효과를 조혈세포의 생존과 회복, 소장움 세포 생존 및 방사선에 의한 apoptosis 유발억제를 통하여 확인하였으며, 이는 독성이 적은 천연물이라는 관점에서 방사선 손상 경감 음료로서 적용이 가능할 것으로 사료되며 추후 유효 분획 및 성분에 관한 연구가 요구된다.

Growth performance, carcass traits and gut health of broiler chickens fed diets incorporated with single cell protein

  • Hombegowda, Gangavadi P.;Suresh, Bypanahalli N.;Shivakumar, Mysore C.;Ravikumar, Puttamallappa;Girish, Bekkere C.;Rudrappa, Satturu M.;Indresh, Huchamanadoddi C.
    • Animal Bioscience
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    • 제34권12호
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    • pp.1951-1962
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    • 2021
  • Objective: This study was conducted to evaluate single cell protein (SCP), produced from Methylococcus species, as a protein source on the growth performance, carcass traits and gut health of broiler chickens. Methods: Ten iso-nitrogenous and iso-caloric diets containing 0 (Control), 2.5%, 5%, 7.5%, and 10% SCP replacing either soybean meal (T1 to T5) or fish meal (T6 to T10) were formulated. Each diet prepared for starter (0 to 14 days), grower (15 to 21 days), and finisher (22 to 42 days) phases was offered to four replicates of 10 chicks each (n = 400). Growth performance at different phases and carcass characteristics and intestinal morphology on 42nd day of trial were measured. Results: Body weight gain in groups fed 2.5% and 5% SCP diets were comparable to control during different phases and cumulatively, however lower (p<0.01) in 7.5% and 10% SCP diets. Feed conversion ratio was better (p<0.01) in 2.5% and 5% SCP diets. Dressing percentage, abdominal fat percentage and meat:bone ratio were not affected (p>0.05) by SCP inclusion in the diets. However, breast percentage was higher (p<0.01) in 2.5% and 5% SCP groups and thigh percentage higher in 7.5% and 10% SCP groups. Total microbial count in duodenum, jejunum and ileum were not affected (p>0.05) by SCP inclusion up to 10% in diets. Duodenal villi length and crypt depth were highest (p<0.01) in group fed 5% SCP diets and lowest in group fed 10% SCP diets. Jejunal villi length and crypt depth as well as ileal villi length were lowest (p<0.01) in group fed 10% SCP diets. Body weight gain, feed consumption, feed conversion ratio and gut health were better (p<0.01) in broilers fed fish meal based diets compared to soybean meal based diets. Conclusion: It was concluded that inclusion of SCP up to 5% replacing soybean meal in broiler diets is beneficial in improving growth rate, breast yield and gut health status.

Dietary protease improves growth performance, nutrient digestibility, and intestinal morphology of weaned pigs

  • Park, Sangwoo;Lee, Jeong Jae;Yang, Boung Mo;Cho, Jin Ho;Kim, Soyun;Kang, Joowon;Oh, Sejong;Park, Dong-Jun;Perez-Maldonado, Rider;Cho, Jee-Yeon;Park, Il-Hun;Kim, Hyeun Bum;Song, Minho
    • Journal of Animal Science and Technology
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    • 제62권1호
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    • pp.21-30
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    • 2020
  • This study was conducted to evaluate effects of dietary protease (PR) on growth performance, nutrient digestibility, and intestinal morphology of weaned pigs. A total of 75 weaned pigs [7.06 ± 0.18 kg of average body weight (BW); 28 day old] were randomly allotted to 3 dietary treatments in a randomized complete block design (blocks = BW and sex): a diet based on corn and soybean meal to meet the requirement of crude protein (CP) as a positive control (PC; CP = 24.49%), a low protein diet as a negative control (NC; CP = 22.51%), and NC + 0.02% PR. The PR used in this study was a commercial product containing 75,000 protease units/g derived from Nocardiopsis prasina produced in Bacillus licheniformis. Pigs were fed the dietary treatments for 6 weeks and the diets containing 0.2% chromic oxide for the last week of this study. Blood, feces, ileal digesta, and ileum samples were collected from randomly selected two pigs in each pen on respective time points. Measurements were growth performance, apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of dry matter (DM), CP, and energy, frequency of diarrhea, packed cell volume (PCV), and ileal morphology of weaned pigs. Pigs fed PC and PR had higher (p < 0.05) final BW, average daily gain (ADG), and gain to feed ratio (G:F) during overall experimental period than those fed NC. Pigs fed PC and PR had higher (p < 0.05) AID or ATTD of DM, CP, or energy than those fed NC. Moreover, pigs fed PR had higher ratio between villus height and crypt depth (p < 0.05) and number of goblet cells (p < 0.05) than those fed NC. Addition of PR decreased (p < 0.05) frequency of diarrhea for the first two weeks after weaning compared with PC and NC. In addition, pigs fed PR had lower (p < 0.05) PCV on d 14 after weaning than those fed PC and NC. In conclusion, addition of PR in nursery diets with a low protein level significantly improved growth performance, nutrient digestibility, and intestinal morphology of weaned pigs.