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Scanning electron microscopy investigation of fibrin networks after thermal injury
2011
Pretorius, Etheresia(University of Pretoria Department of Anatomy) | Olivier, Jeané(University of Pretoria Department of Anatomy) | Oberholzer, Hester M.(University of Pretoria Department of Anatomy) | van der Spuy, Wendy J.(University of Pretoria Department of Anatomy)
Injury due to burning is known to impact on coagulation and haemostasis by disturbing the coagulation cascade and is also associated with impaired fibrinolysis. Also, venous thrombosis, pulmonary embolism and hypercoagulability are common during thermal injury. Using a Wistar albino rat model, we investigated in this study whether burn injury affects the ultrastructure of the fibrin networks. A typical fibrin network will contain mostly major, thick fibres with minor, thin fibres distributed amongst them. We found that the clot architecture changes after burn injury, showing more prominent minor, thin fibres in a netted appearance. Also, the clot showed areas of matted fibrin. We suggest that the thrombotic events associated with burn injury are due to the thickened and netlike areas formed when thrombin activates the coagulation cascade. This is due to impaired fibrinolysis activities, causing the resulting fibrin clots not to be successfully disseminated. Small fragments of these netted, clumped areas may therefore break loose and lead to thrombotic events after burn injuries. The current study therefore provided morphological evidence for thrombotic events associated with burn injury.
Afficher plus [+] Moins [-]Survey of the livestock ticks of the North West province, South Africa
2011
Spickett, Arthur M.(ARC-Onderstepoort Veterinary Institute Parasites, Vectors and Vector-borne Diseases Programme) | Heyne, Ingard H.(ARC-Onderstepoort Veterinary Institute Parasites, Vectors and Vector-borne Diseases Programme) | Williams, Roy(ARC-Onderstepoort Veterinary Institute Information Systems Programme)
Ticks, as vectors of disease and damage agents, impact directly and indirectly on the economy of the livestock industry in southern Africa. This study surveyed the occurrence and distribution of ticks infesting livestock across the North West province, South Africa. During three phases in consecutive years, officers of the provincial Veterinary Department collected specimens monthly from livestock hosts at specified sites across the province. Data analysis constituted the fourth phase of the study. A total of 1090 collections from 265 sites yielded 42 566 tick specimens, comprising 22 different tick species (18 ixodids, 4 argasids). The specimens represent all of the major tick vectors of disease that occur in South Africa. The major tick-borne diseases (i.e. heartwater, both African and Asiatic bovine babesiosis and anaplasmosis) were found to be prevalent mainly in the north-eastern region of the province, which also displayed the highest tick species diversity. The central region appears transitory to some of the major vectors. Although some tick species were contained within specific regions, others were widespread across the province. Associated serology data show that most herds sampled in areas endemic for babesiosis and anaplasmosis in the north-eastern region are endemically unstable and at risk to these tick-borne diseases should vector control measures become ineffective.
Afficher plus [+] Moins [-]Natural in utero infection of neonatal calves with bovine viral diarrhoea virus on a large dairy farm in Saudi Arabia
2011
Abuelzein, Eltayb M.(King Abdulaziz University King Fahad Medical Research Centre) | Al-Khaliyfa, Mofeed A.(Almarai Company) | Gameel, Ahmed A.(University of Khartoum Faculty of Veterinary Medicine)
The dairy industry is a large and important business in Saudi Arabia. Although farms are administered to high international standards, some reproduction problems, of uncertain aetiology, are encountered. The most frequently seen are conception failures, abortions, stillbirths and the birth of weak or malformed calves. These conditions are suggestive of bovine viral diarrhoea virus (BVDV) infection. Unfortunately, very little published information is available regarding the impact of this disease on cattle populations in Saudi Arabia. As a consequence, the present study was carried out and is the first of its kind in Saudi Arabia and the Gulf region. The aim of the study was to elucidate the role of in utero BVDV infection leading to the birth of weak or malformed calves on a large dairy farm in Saudi Arabia. The study was divided into two parts. Firstly, apparently healthy neonatal calves were sampled for the detection of pre-colostral serum antibodies to BVDV. The presence of these antibodies indicates exposure of the foetus to BVDV during the last two trimesters of gestation. Secondly, tissue samples from malformed neonatal calves were examined for the presence of BVDV antigens. Detection of such antigens confirms exposure of the foetus to the virus during the first trimester of gestation. The results of the investigation indicated that 36.1% of the neonatal calves were exposed to BVDV infection in utero. This is higher than what has been reported in the literature and suggests that dairy farmers in the Arabian Peninsula need to be made aware of the dangers of BVDV infections in their herds. The epidemiological significance of the results is discussed.
Afficher plus [+] Moins [-]Natural <i>in utero</i> infection of neonatal calves with bovine viral diarrhoea virus on a large dairy farm in Saudi Arabia
2011
Eltayb M. Abuelzein | Mofeed A. Al-Khaliyfa | Ahmed A. Gameel
The dairy industry is a large and important business in Saudi Arabia. Although farms are administered to high international standards, some reproduction problems, of uncertain aetiology, are encountered. The most frequently seen are conception failures, abortions, stillbirths and the birth of weak or malformed calves. These conditions are suggestive of bovine viral diarrhoea virus (BVDV) infection. Unfortunately, very little published information is available regarding the impact of this disease on cattle populations in Saudi Arabia. As a consequence, the present study was carried out and is the first of its kind in Saudi Arabia and the Gulf region. The aim of the study was to elucidate the role of in utero BVDV infection leading to the birth of weak or malformed calves on a large dairy farm in Saudi Arabia. The study was divided into two parts. Firstly, apparently healthy neonatal calves were sampled for the detection of pre-colostral serum antibodies to BVDV. The presence of these antibodies indicates exposure of the foetus to BVDV during the last two trimesters of gestation. Secondly, tissue samples from malformed neonatal calves were examined for the presence of BVDV antigens. Detection of such antigens confirms exposure of the foetus to the virus during the first trimester of gestation. The results of the investigation indicated that 36.1% of the neonatal calves were exposed to BVDV infection in utero. This is higher than what has been reported in the literature and suggests that dairy farmers in the Arabian Peninsula need to be made aware of the dangers of BVDV infections in their herds. The epidemiological significance of the results is discussed.
Afficher plus [+] Moins [-]Efficacy test of sustained-release somatotropin by implantation in steer, cow and barrow
2011
Kim, N.J., Hyechon University, Daejeon, Republic of Korea
Sixteen steers were used to investigate the efficacy of the sustained-release implant of bovine somatotropin (bST) in improving growth and feed:gain ratio during 12 weeks. Administration of the 400 mg bST implant resulted in a 16.1% increase in growth rate, and this increase was significant (p less than .05). The use of the sustained-release implant did not alter (p greater than .05) feed intake and feed:gain ratio. Thirty-four cows were used to investigate the efficacy of the sustained-release implant of bST in milk production during 4 weeks. Administration of the 200 mg bST implant resulted in an 8.7% increase in milk production, and this increase was significant (p less than .05). Twenty-four barrows were used to investigate the efficacy of the sustained-release implant of porcine somatotropin (pST) in improving growth, feed:gain ratio and backfat thickness during 6 weeks. Administration of the 120 mg pST implant resulted in a 11.4% increase in feed:gain ratio and a 60% decrease in backfat thickness, and these results were significant (p less than .05). But the use of the sustained-release implant did not alter (p greater than .05) growth rate and feed intake.
Afficher plus [+] Moins [-]Quantification and genotyping of PCV2 DNA in the tissues of PCV2-infected conventional pigs with different clinical signs
2011
Kim, H.K., Seoul National University, Seoul, Republic of Korea | Luo, Yuzi, Seoul National University, Seoul, Republic of Korea | Moon, H.J., Green Cross Veterinary Products, Yongin, Republic of Korea | Park, S.J., Seoul National University, Seoul, Republic of Korea | Rho, S.M., Seoul National University, Seoul, Republic of Korea | Han, J.Y., Seoul National University, Seoul, Republic of Korea | Nguyen, Van Giap, Seoul National University, Seoul, Republic of Korea | Park, B.K., Seoul National University, Seoul, Republic of Korea
This study was focused on the genotyping and quantification of Porcine circovirus type 2 (PCV2) in thirty PCV2-positive pigs with different clinical symptoms (PCV2-infected without wasting, PCV2-infected with wasting, PCV2-infected with wasting and lymphoid depletion). The quantity of PCV2 DNA in diverse tissues was significantly differed among these groups. (One-way ANOVA test, p less than 0.001) Interestingly, PCV2-DNA load in tissues of PCV2-infected pigs without wasting and PCV2-infected pigs with wasting and lymphoid depletion were not significantly differed (p = 0.38), while they were all significantly higher when compared with PCV2-infected pigs with wasting-only. PCV2 DNA quantity in tissues was significantly higher in PCV2a and 2b co-infected pigs compared to the PCV2b only-infected pigs (Wilcoxon test, p = 0.039). The PCV2a and 2b co-infected pigs had increased wasting and lymphoid depletion rate but it was not statistically significant. Therefore, this cross-sectional study suggested that PCV2 DNA load in tissues was diverse by clinical and histological findings. Furthermore, co-infection of PCV2a and 2b affected to the PCV2 DNA load in tissues with increased rate of wasting and lymphoid depletion.
Afficher plus [+] Moins [-]Protective effects and immunogenicity of Salmonella Enteritidis killed vaccine strains selected from virulent Salmonella Enteritidis isolates
2011
Kang, Z.W., Kangwon National University, Chuncheon, Republic of Korea | Won, H.K., ChoongAng Vaccine Laboratories, Daejeon, Republic of Korea | Kim, E.H., ChoongAng Vaccine Laboratories, Daejeon, Republic of Korea | Noh, Y.H., ChoongAng Vaccine Laboratories, Daejeon, Republic of Korea | Choi, H.W., ChoongAng Vaccine Laboratories, Daejeon, Republic of Korea | Hahn, T.W., Kangwon National University, Chuncheon, Republic of Korea
Salmonella Enteritidis (SE) has been a major causative agent of food-borne human disease due to consumption of contaminated eggs and poultry meat. To prevent SE infection in poultry, and therefore minimize human infections, vaccination with either killed or live SE vaccine is suggested. We evaluated a newly developed killed bacterin using a representative SE isolate in Korea. Among pool of SE isolates, two highly virulent isolates (the one isolate from chicken, the other from human) were selected by measuring mortality in mouse and chickens administered. The chickens were injected intramuscularly with killed vaccine and were challenged with highly virulent SE strain 3 week after vaccination. The recovered colony count (cfu/g) of spleen and cecal content in the vaccinated groups was reduced compared with those of the unvaccinated control group. The antibody level in the vaccinated groups was higher at 3 week post vaccination. These results indicate that vaccination with killed vaccine was effective in preventing the infection of virulent SE. Further study for a large number of layers should be needed for the effect of egg production, SE shedding in feces, persistence of antibody level.
Afficher plus [+] Moins [-]Sequence analysis of segment A gene of a very virulent infectious bursal disease virus recently isolated in Korea
2011
Oh, H.S., Kangwon National University, Chuncheon, Republic of Korea | Lee, J.H., Kangwon National University, Chuncheon, Republic of Korea | Kwon, H.M., Kangwon National University, Chuncheon, Republic of Korea | Sung, H.W., Kangwon National University, Chuncheon, Republic of Korea
Infectious bursal disease virus (IBDV) is a member of the Avibirnavirus genus of the Birnaviridae family which genome consists of two segments (A and B) of double stranded RNA. Segment A gene of KNU08010 isolate, which was isolated from a 15-day-old chicken flock in 2008, was sequenced and compared with other IBDV isolates including SH/92 strain, the first Korean very virulent (vv) IBDV isolate. The amino acid sequences of segment A gene showed that KNU08010 had 99.2% homology with SH92 strain. KNU08010 isolate had specific amino acids A222, I242, I256, I294 and S299 which are highly conserved among vvIBDV strains. Phylogenetic analysis based on the nucleotide sequences of variable region of the VP2 gene of 18 IBDV strains revealed that KNU08010 was grouped with vvIBDVs and was closely related to Korean vvIBDVs isolated from wild birds.
Afficher plus [+] Moins [-]Neonatal isoerythrolysis in Thoroughbred foals
2011
Kwon, D.Y., Korea Food and Drug Administration, Seoul, Republic of Korea | Choi, S.K., Kyungpook National University, Daegu, Republic of Korea | Cho, Y.J., Jangsu Stud Farm, Korea Racing Authority, Jangsu, Republic of Korea | Cho, G.J., Kyungpook National University, Daegu, Republic of Korea
Two 4-day-old Thoroughbred foals with acute clinical signs of depression, elevated pulse and respiratory rates, anemia, and jaundice were referred to the equine hospital of Korea Racing Authority. The foals were seemingly normal at birth, but showed clinical signs such as abnormal behavior, jaundice and anemia suddenly after ingestion of the mare's colostrum, followed by death at 4 days after birth. According to the results of the hematology, serum chemistry analysis, jaundice foal agglutination test, and blood groups test, the foals were diagnosed as neonatal isoerythrolysis (NI) caused by the mare's antibodies. These results suggested that the pregnant mares have a potential for NI.
Afficher plus [+] Moins [-]The polymorphism of Theileria buffeli major surface protein associate with their clinical signs in holstein in Korea
2011
Yu, D.H., Chonbuk National University, Jeonju, Republic of Korea | Li, Y.H., Chonbuk National University, Jeonju, Republic of Korea | Chae, J.S., Seoul National University, Seoul, Republic of Korea | Park, J.H., Chonbuk National University, Jeonju, Republic of Korea
Theileria (T.) buffeli (formerly T. sergenti/T. orientalis) is the major hemo-protozoan distributed in the Far East Asian countries such as Korea, China and Japan. It is responsible for the clinical symptoms of anorexia, ateliosis, anemia, fever and icterus. It also causes abortion and sudden death under severe cases, resulting in economic losses for many livestock farms. The objective of this study was to analyze the genetic diversity of the major surface protein (Msp) gene in T. buffeli in Holstein in Korea, and we characterized the association of the diversification of the Msp gene and its relationship with the pathogenicity of Theileria. For this, complete blood counts and Theileria PCR sequence analysis were performed from 57 Holstein in Jeju Island. A total of 26 PCR positive Holstein (16 anemic and 10 non-anemic) were then randomly selected based on 18s rRNA sequence typing of the Theileria Msp gene. The DNA sequence of the T. buffeli Msp gene in Holstein showed 99.0%, 99.2%, 99.9%, 99.5%, 98.7%, 98.4% and 98.4% homology with T. sergenti, Theileria spp., T. sergenti, Theileria spp., Theileria spp., Theileria spp. and Theileria spp., respectively. The result showed a genetic variation of 57.7% (type Ⅰ), 3.8% (type Ⅱ), 15.4% (type Ⅲ), 7.7% (type Ⅳ), 13.5% (type Ⅴ) and 1.9% (type Ⅵ). Type Ⅰ is the most frequent type in both anemic and non-anemic Holstein while type Ⅱ was found in only non-anemic Holstein. This results of our study help confirm the diversity of Msp gene types and demonstrate that the gene type distribution of Msp genes varies among Theileria-infected Holstein in Jeju Island.
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