Anticoccidial Effect of CS 32 Compounds Against Eimeria tenella Infection in Chickens

Coccidiosis-causing Eimeria species are transmitted in poultry via the oral-fecal route and can lead to hemorrhagic diarrhea and mortality. This results in enormous economic losses in the poultry industry. Furthermore, its resistance to some currently used antibiotics is increasing. This has prompted the development of new alternative drug therapies that address the issue of chemical-free meat production. Effective management of infectious diseases in veterinary practice includes the induction of protective and adaptive immunity by treatment with an alternative agent. In this study, we evaluated the anticoccidial effects of dietary supplementation of Chosun University (CS) 32 compounds (0.1% and 1.0%) against Eimeria tenella, which was isolated and purified from the supernatant of culture broth of Bacillus strain (KCTC18250P), as well as its effect on the growth rate and feed efficiency in chickens. Overall, we observed a decrease in lesion scores and oocyte output in CS 32 compounds-treated chickens. We concluded that 0.1% CS 32 compounds displayed anticoccidial effects against E. tenella infection.

Effect of probiotic 379D as an alternative to antibiotics for feed supplementation in broiler chickens / 동물의과학연구지

Antibiotics have been used to prevent disease, promote growth rate, and improve feed efficiency. However, the use of antibiotics in livestock has been restricted worldwide due to problems such as bacterial resistance. Therefore, probiotics among alternatives to antibiotics have gained attention in the livestock feed industry these days. This study was conducted to investigate the effects of dietary supplementation with probiotic 379D on safety, growth rate, and feed efficiency. In this study, bacterial strain 379D was isolated from soil and identified as a Bacillus sp. according to 16S rRNA sequence analysis. In an in vitro test, in-gel activity assay and antimicrobial susceptibility test were conducted to evaluate 379D. In an in vivo study, 379D was administered at concentrations of 0.1% and 1% to broiler chickens for 28 days. The results of in-gel activity assay and antimicrobial susceptibility test showed that strain 379D had broad spectrum antimicrobial activity. Furthermore, no adverse 379D-related effects were observed in 0.1% and 1% groups. Feed efficiency was higher in the 379D-treated groups than in the control group. In conclusion, 379D is expected to be used as a safe alternative to antibiotics in a feed supplement and will improve feed efficiency in broiler chickens.

Evaluation of short-term ex vivo culture with air/liquid system of porcine cornea / 동물의과학연구지

Regarding therapies for treatment of corneal wounds, ex vivo corneal culture is the most effective for minimizing expensive animal studies. Eighteen porcine enucleated eyes were soaked in 0.2% povidone iodine solution for disinfection prior to cornea excision. Subsequently, corneas were excised from whole eyes and filled with an agar/medium mixture. Corneas were transferred into culture dishes, after which culture medium was added until the limbus was covered. Cultures were then placed onto a plate rocker to mimic blinking action, followed by incubation at 37degrees C and 5% CO2. Corneas were harvested on Days 0, 3, and 7 after incubation, and optical coherence tomography (OCT) was performed on Day 7. Two eyes from each group were fixed in 2% glutaraldehyde/4% paraformaldehyde for low vacuum scanning electron microscopy (LV-SEM), and four eyes from each group were fixed in 10% neutral-buffered formalin for histological analysis. OCT results showed that central corneal thickness significantly increased by Day 7 compared to Day 0 (P<0.05). Using LV-SEM, gaps between endothelial cells were detected on Day 7 of ex vivo culture. In the histological evaluation, four to five stratified squamous cell layers, wing cells, and basal cells in the epithelium as well as flat-shaped keratocytes in the stroma were found on Day 0. By Day 7, stratified squamous cells and basal cells had decreased in number, and slightly round-shaped keratocytes were observed; however, the number of keratocytes was similar to that on Day 0. In this short-term ex vivo culture, epithelium and endothelium were sensitive to culture, whereas stroma and keratocytes were well maintained. An additional deswelling method will be needed to obtain more successful results in porcine corneal ex vivo culture.

Evaluation of biocompatibility of alpha-1,3 galactosyltransferase knockout pig bone graft in a rat calvarial defect model / 동물의과학연구지

The current study was conducted to evaluate the biocompatibility of alpha-1,3 galactosyltransferase knockout pig bone graft in a rat calvarial defect model. Porcine cancellous bones were harvested from general and alpha-gal KO pigs and washed with 70% ethanol solution and normal saline. Bone pieces of the alpha-gal KO pig underwent a chemical treatment process to delipidize and deproteinize the bone. Bone graft particles were freeze-dried and stored at -70degrees C until use. Each bone graft was implanted into the rat calvarial defect in a fresh general pig, fresh transgenic pig, and chemical-treated pig bone group. There was no systemic adverse effect on hematology or necropsy findings in all groups at 1 week and 4 weeks. In the microcomputed tomography analysis, bone volume increased significantly in the chemical-treated transgenic pig bone group, whereas bone mineral density decreased significantly in the fresh general pig bone group compared with other groups. Histological evaluation showed cellular infiltration located at the margin of the bone graft particles, especially in the fresh general pig bone group. These results indicate that fresh general pig bone can elicit a greater local inflammatory response than fresh transgenic pig bone. Further, chemical-treated transgenic pig bone graft was less immunogenic than fresh bone graft. In conclusion, transgenic pig bone is a more biocompatible graft material. In addition, chemical treatment can reduce bone graft immunogenicity by delipidizing and deproteinizing bone.

Effects of mesenchymal stem cells treated with BMP-2 and VEGF on regeneration of large bone defects / 동물의과학연구지

This study evaluated the possibility of clinical application using matrigel-based bioceramic/polymer scaffolds treated with bone morphogenetic protein, angiogenic factor, and mesenchymal stem cells (MSCs) for new bone formation. In the in vitro study, bone morphogenetic protein (BMP-2) and vascular endothelial growth factor (VEGF) containing matrigel, which is a basement membrane gel, was injected into HA/PCL scaffolds to estimate the release rates of growth factors. In the in vivo study, BMP-2, VEGF, and MSCs with matrigel-based scaffolds were implanted into rat femoral segmental defects, and new bone formation was evaluated at 4 and 8 weeks. In the results, the release rates of BMP-2 and VEGF explosively increased by day 5. For the in vivo study results, radiological evaluation revealed that the matrigel-based HA/PCL scaffolds with BMP-2 and VEGF grafted (M+B+V) and matrigel-based HA/PCL scaffolds with BMP-2, VEGF, and MSC grafted (MSC) groups showed increased bone volume and bone mineral density. Moreover, in the histological evaluation, large new bone formation was observed in the M+B+V group, and high cellularity in the scaffold was observed in the MSC group. In conclusion, grafted matrigel-based HA/PCL scaffolds with BMP-2, angiogenic factor, and MSCs increased new bone formation, and in clinical cases, it may be effective and useful to enhance healing of delayed fractures.

The effect of angiogenic factors with HA/PCL scaffold containing matrigel in a rat calvarial defect model / 동물의과학연구지

The current study was conducted in order to investigate bone formation using matrigel and angiogenic factors with HA and poly epsilon-caprolactone (HA/PCL) in a rat calvarial defect model. Calvarial defect formation was surgically created in Sprague Dawley rats (n=36). Rats in the control group (CD group, n=6) did not receive a graft. The HA/PCL scaffold was grafted with matrigel (M-HA/PCL group, n=6) or without matrigel (HA/PCL group, n=6); and 100 ng of vascular endothelial growth factor with HA/PCL scaffold containing matrigel (VEGF100 group, n=6), 100 ng (PDGF100 group, n=6) and 300 ng (PDGF300 group, n=6) of PDGF with HA/PCL scaffold containing matrigel were grafted in calvarial defects, respectively. Four weeks after surgery, bone formation was evaluated with micro computed tomography (micro CT) scanning, and histologically. According to the results, bone mineral density was significantly increased in the VEGF100, PDGF100, and PDGF300 groups compared to the HA/PCL group, in which angiogenic factors were not applied. In histological evaluation, more new bone formation around scaffolds was observed in the PDGF100 and the PDGF300 groups, compared with the VEGF100 group. Thus, the results indicate that HA/PCL containing matrigel with VEGF and PDGF is an effective grafting material for enhancement of bone formation in critical-sized bone defects. Especially, due to its price and capacity for bone formation, PDGF may be more effective than VEGF.

Efficacy of alcohol-free cetylpyridinium chloride on periodontal disease in beagle dogs via drinking water additive and oral gel / 동물의과학연구지

This study was conducted in order to examine the effects of alcohol-free cetylpyridinium chloride drinking water additive and oral gel on clinical parameters related to periodontal disease in beagle dogs. This study was conducted with healthy 15 beagle dogs. Following a professional teeth cleaning procedure, dogs were divided into three groups. Dogs in the control group received nothing, those in the drinking water additive (DWA) group received 800 ml water with 15 ml of alcohol-free cetylpyridinium chloride drinking water additive daily, and those in the Oral gel (OG) group were treated with oral gel containing alcohol-free cetylpyridinium chloride and 0.05% chlorhexidine gluconate daily. Clinical parameters, including plaque index (PI), calculus index (CI), and gingivitis index (GI) were evaluated at two and four weeks. Dogs in the DWA and OG groups had significantly less plaque than dogs in the control group at two and four weeks (P<0.01, P<0.05). And, at four weeks, CI was significantly lower in the OG group compared to the control group (P<0.05). On GI, similar scores were recorded for all groups during the experimental period. No significant difference was observed between the DWA group and the OG group. The effect of alcohol-free cetylpyridinium chloride drinking water additive was similar to the result for alcohol containing cetylpyridinium chloride mouthwash reported in a previous study. The effect in control of periodontal disease was better in the OG group because of additional chlorhexidine gluconate. However, use of drinking water additive will be more convenient for owners; thus, it will be more effective for achievement of long-term results.

Effects of probiotic CS-32 as a feed additive on growth performance of broiler chickens / 동물의과학연구지

In the livestock feed industry, antibiotics are used to prevent disease, promote growth rate, and improve feed efficiency. However, antibiotic supplementation to animal feed results in increased bacterial resistance to antibiotics as well as antibiotic residues in animal products, which can negatively affect human health. Therefore, alternative sources of antibiotics are needed. Probiotics as an alternative to antibiotics in animal feed have been shown to increase feed efficiency and growth rate by improving microbial balance. Further, Bacillus sp. produces a wide spectrum of antibacterial peptides. The present study was conducted to investigate the effects of dietary supplementation with CS-32 on safety, growth rate, and feed efficiency. Antibacterial substance (5697.9 molecular weights) produced by CS-32 was isolated and purified from culture broth. Moreover, the results of minimal inhibitory concentration (MIC) test confirmed the excellent antibacterial effect of CS-32. In vivo, 0.1% and 1% CS-32 were fed to broiler chickens for 28 days. Feed efficiency was slightly higher in groups of chickens supplemented with 0.1% and 1% CS-32 than those of the control group. CS-32 had no significant effect on necropsy findings, hematology, or serum biochemistry, and there was no mortality. These results suggest that CS-32 among various biologically active substances may be safe and effective as a feed additive to improve growth rate and feed efficiency.

The effect of platelet rich plasma in bone formation on implant installation in the tibia of beagle dogs

INTRODUCTION: The purpose of this study is to evaluate the effect of platelet rich plasma in bone formation and osseointegration of implant installed in the bone marrow space. MATERIALS AND METHODS: Five beagle dogs were used as experimental animals. Two implants were installed on each tibia in the dogs. Implants of the control group were installed with no additional graft. Those of the experimental group 1 were installed with autogenous bone graft from the ilium autogenous bone. Platelet rich plasma (PRP) alone was used in experimental group 2 and the mixture of PRP and autogenous bone was used in experimental group 3. The animals were sacrificed at 8 weeks after implantation. The parts of tibia containing implant were harvested and radiographs were taken for radiographic examination. The specimens were prepared for histological examination and histomorphometric analysis of implant-bone contact ratios. RESULTS: 1. All implants showed sufficient osseointegration in the cortical bone radiographically and histologically, but osseointergration in the marrow space was not satisfactory. 2. Histomorphometrically, the implant-bone contact ratios in the bone marrow was sequentially high in the experimental group 3 (autogenous bone + PRP group), group 1 (autogenous bone group), group 2 (PRP group), and control group (non-additive). 3. It was verified that there was statistical significance between two experimental groups (group 1 and 3) and the other groups (group 2 and control group). (P<0.005) 4. However, there was no statistical significance between group 3 and group 1, also group 2 and control group respectively. CONCLUSION: These results suggest that platelet rich plasma is effective to osseointegration in the implant installation but there is no statistical significance.

Scintigraphic Assessment of Renal Function Using 99mTc-DTPA in Miniature Pigs with Unilateral Ureteral Obstruction / 한국실험동물학회지

This study was performed to investigate the proper method for evaluating renal function in miniature pigs with unilateral ureteral obstruction. Experimental unilateral renal damage was induced after ligation of unilateral right ureter in 3 miniature pigs. On the 3rd post-operative day, scintigraphic images were obtained after 12 mCi of 99mTc-diethylentriamene pertaacetate (DTPA) intravenous injection. Renography showed that radiopharmaceutical uptakes in the right kidney were lower than those of left kidney uptakes as early as at 3 days after surgical operation. The static images of 99mTc-DTPA enabled us to measure the relative renal function in miniature pigs with unilateral ureteral obstruction. In conclusion, renography using 99mTc-DTPA was the useful diagnostic method to evaluate the renal function in miniature pigs.