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61.
Tendons regenerate poorly due to a dense extracellular matrix and low cellularity. Cellular therapies aim to improve tendon repair using mesenchymal stem cells and tenocytes; however, a current limitation is the low proliferative potential of tenocytes in cases of severe trauma. The purpose of this study was to develop a method useful in veterinary medicine to improve the differentiation of Peripheral Blood equine mesenchymal stem cells (PB-MSCs) into tenocytes. PB-MSCs were used to study the effects of the addition of some growth factors (GFs) as TGFβ3 (transforming growth factor), EGF2 (Epidermal growth factor), bFGF2 (Fibroblast growth factor) and IGF-1 (insulin-like growth factor) in presence or without Low Level Laser Technology (LLLT) on the mRNA expression levels of genes important in the tenogenic induction as Early Growth Response Protein-1 (EGR1), Tenascin (TNC) and Decorin (DCN). The singular addition of GFs did not show any influence on the mRNA expression of tenogenic genes whereas the specific combinations that arrested cell proliferation in favour of differentiation were the following: bFGF2 + TGFβ3 and bFGF2 + TGFβ3 + LLLT. Indeed, the supplement of bFGF2 and TGFβ3 significantly upregulated the expression of Early Growth Response Protein-1 and Decorin, while the use of LLLT induced a significant increase of Tenascin C levels. In conclusion, the present study might furnish significant suggestions for developing an efficient approach for tenocyte induction since the external administration of bFGF2 and TGFβ3, along with LLLT, influences the differentiation of PB-MSCs towards the tenogenic fate.  相似文献   
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1. Genetically lean (LL) or fat (FL) chickens were fed from 28 to 42 d of age on one of 6 diets with different protein contents (from 73 to 208 g/kg). In order to keep a constant amino acid balance the experimental diets were made by diluting a well-balanced protein-rich diet with a protein-free diet. 2. Dietary protein influenced the growth rate of both genotypes similarly. However, maximum weight gain was reached in LL at a lower protein intake than in FL. 3. Regression between total protein gain (body protein + feather protein) or body protein gain and protein intake exhibited significantly different slopes, that of LL being superior to that of FL. 4. At a given protein intake, feather protein gain was also superior in LL to FL. Moreover feather protein, as a percentage of total protein gain, was superior in LL to FL. When the dietary protein fell below 126 g/kg, feather protein represented a higher proportion of total protein gain. 5. Multiple linear regressions of protein intake (as the dependent variable), and body weight and protein gain or weight gain (as the independent variables) suggest that the maintenance requirement for protein is similar in both lines but that the protein efficiency for growth is significantly superior in LL. 6. In a second experiment both genotypes were offered either a single high protein diet (232 g/kg) or a single medium protein diet (186 g/kg) or had free-choice between a high (269 g/kg) and a low protein (145 g/kg) diet. In free-choice feeding, FL chickens selected an overall dietary protein content which was significantly lower (179 v. 200 g/kg) to that of LL. In both genotypes, free-choice feeding led to fatter and less efficient chickens than predicted by the linear regression between adiposity or food conversion and protein content.  相似文献   
64.
Five-day-old bobwhite quails were inoculated with reovirus and Cryptosporidium previously isolated from the intestinal contents of young, commercially raised bobwhite quails experiencing severe enteritis. Quails inoculated with reovirus alone did not develop clinically apparent disease, infection was localized principally in the intestinal tract, and no lesions were detected. Quails inoculated with Cryptosporidium, alone or with reovirus, developed severe enteritis with high mortality and marked growth depression. Cryptosporidia caused blunting of intestinal villi and provoked a mononuclear cell response in the lamina propria. The severity of intestinal lesions correlated with numbers of parasites. An apparent synergistic effect in dually infected quails was indicated by enhanced Cryptosporidium oocyst shedding, greater numbers of cryptosporidia in the intestinal tracts, and systemic reovirus infection. In addition, multifocal liver necrosis was detected in dually infected quails but was absent in quails infected with only reovirus or Cryptosporidium. The results suggest that Cryptosporidium promoted systemic spread of reovirus, and reovirus intensified Cryptosporidium infection, but no significant synergistic effect on mortality or weight gain was detected. The most important agent in the naturally occurring acute enteritis of bobwhite quails was Cryptosporidium.  相似文献   
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66.
Effect of Foot and Mouth disease (FMD) vaccination was studied on semen quality parameters of 19 Karan Fries (KF) and eight Murrah (MU) breeding bulls during the period 2002 to 2004 at Artificial Breeding Complex, NDRI, Karnal. A total of non-vaccinated 155 KF and 72 MU bulls' ejaculates were taken as control, while 169 KF and 51 MU bulls' ejaculates, collected after vaccination, were used to study the effect of vaccination stress. The results showed that FMD vaccination had no significant (P > 0.05) effect on ejaculate volume and total volume per day of semen in both KF and MU bulls. Volume of semen increased slightly during post-vaccination period in both the breeds. After FMD vaccination, there was significant (P < 0.01) decrease in mass activity (2.27 ± 0.06 vs. 1.67 ± 0.07 and 2.49 ± 0.09. vs. 1.75 ± 0.10, for KF and MU, respectively), initial motility (56.89 ± 0.03% vs. 44.62 ± 0.02% and 62.26 ± 0.04% vs. 47.08 ± 0.05%, for KF and MU, respectively), sperm concentration (754.19 ± 23.96 vs. 554.14 ± 22.95 × 106/ml and 848.61 ± 33.65 vs. 571.57 ± 39.99 × 106/ml, for KF and MU, respectively), and total sperm output per ejaculate (3,685.94 ± 158.40 vs. 2,781.54 ± 151.70 × 106 and 2,218.75 ± 133.14 vs. 1,582.84 ± 158.20 × 106, for KF and MU, respectively). Application of FMD vaccine had significantly (P < 0.05) adverse effect on most of the seminal attributes during post-vaccination in KF and MU buffalo bulls. So, the spermiograms affected following vaccination suggest that in bovines, the semen collection and preservation should be suspended till normal fertility of sperm is restored to avoid the failure of conception from artificial insemination using such semen.  相似文献   
67.
Pharmacokinetics and milk levels of ceftriaxone were studied in healthy and endometritic cows following single intravenous administration. The drug was detected up to 8 h of dosing in plasma of healthy and endometritic cows and the drug disposition followed three-compartment open model. The values of Vdarea, AUC, t1/2β, ClB, MRT and P/C ratio were 0.50 ± 0.19 L.kg−1, 62.2 ± 23.3 μg.ml−1.h, 1.02 ± 0.07 h, 0.30 ± 0.09 L.kg−1.h−1, 1.55 ± 0.25 h and 0.52 ± 0.27, respectively, in healthy and 1.55 ± 0.52 L.kg−1, 37.0 ± 17.1 μg.ml−1.h, 1.56 ± 0.25 h, 0.56 ± 0.14 L.kg−1.h−1, 2.14 ± 0.34 h and 1.44 ± 0.60, respectively, in endometritic cows. The drug was detected in milk for 36 h after administration. For MIC90 of 0.5 μg.ml−1 the most appropriate dosage for ceftriaxone, would be 9.0 mg.kg−1 repeated at 6 h intervals for the treatment of endometritis in cows.  相似文献   
68.
Inclusion-body hepatitis was diagnosed in 1-day-old turkeys experiencing above-average mortality. At necropsy, turkeys appeared anemic and had pale yellow livers. Histopathologic examination of affected livers revealed diffuse hepatic degeneration and multifocal necrosis, with approximately 70% of the hepatocytes containing large, basophilic, intranuclear inclusion bodies. An adenovirus was isolated from affected livers and identified as a group I avian adenovirus by indirect immunofluorescence.  相似文献   
69.
Dichelobacter nodosus is the principal cause of ovine footrot and strain virulence is an important factor in disease severity. Therefore, detection and virulence determination of D. nodosus is important for proper diagnosis of the disease. Today this is possible by real-time PCR analysis. Analysis of large numbers of samples is costly and laborious; therefore, pooling of individual samples is common in surveillance programs. However, pooling can reduce the sensitivity of the method. The aim of this study was to develop a pooling method for real-time PCR analysis that would allow sensitive detection and simultaneous virulence determination of D. nodosus. A total of 225 sheep from 17 flocks were sampled using ESwabs within the Swedish Footrot Control Program in 2014. Samples were first analysed individually and then in pools of five by real-time PCR assays targeting the 16S rRNA and aprV2/B2 genes of D. nodosus. Each pool consisted of four negative and one positive D. nodosus samples with varying amounts of the bacterium. In the individual analysis, 61 (27.1%) samples were positive in the 16S rRNA and the aprV2/B2 PCR assays and 164 (72.9%) samples were negative. All samples positive in the aprV2/B2 PCR-assay were of aprB2 variant. The pooled analysis showed that all 41 pools were also positive for D. nodosus 16S rRNA and the aprB2 variant. The diagnostic sensitivity for pooled and individual samples was therefore similar. Our method includes concentration of the bacteria before DNA-extraction. This may account for the maintenance of diagnostic sensitivity. Diagnostic sensitivity in the real-time PCR assays of the pooled samples were comparable to the sensitivity obtained for individually analysed samples. Even sub-clinical infections were able to be detected in the pooled PCR samples which is important for control of the disease. This method may therefore be implemented in footrot control programs where it can replace analysis of individual samples.  相似文献   
70.
Livestock production is an integral part of the rain-fed and irrigated agriculture system in Pakistan. Animal production is closely interlinked with the cropping systems and play a crucial role in the rural economy. Participatory rural appraisals and economic opportunity surveys were conducted in two ecological zones (irrigated and rain-fed) and two dairy production systems (peri-urban and mixed livestock). Major constraints in animal health, nutrition and reproduction were identified and interventions were suggested to overcome these difficulties. The economic opportunity survey revealed that maximum opportunity to enhance farmers’ income is to increase milk production per day per animal, which can be accomplished through coordinated improvements in nutrition, reproduction and genetics.  相似文献   
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