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91.
Chiara Gomiero Giulia Bertolutti Tiziana Martinello Nathalie Van Bruaene Sarah Y. Broeckx Marco Patruno Jan H. Spaas 《Veterinary research communications》2016,40(1):39-48
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
92.
Long‐term follow‐up of renal function assessing serum cystatin C in dogs with diabetes mellitus or hyperadrenocorticism 下载免费PDF全文
93.
94.
Estimation of the standardized ileal digestible lysine requirement for primiparous pregnant sows 下载免费PDF全文
M. Shi C. X. Shi Y. K. Li D. F. Li F. L. Wang 《Journal of animal physiology and animal nutrition》2016,100(2):287-293
This experiment was conducted to determine the optimal standardized ileal digestible lysine (SID Lys) level in diets fed to primiparous sows during gestation. A total of 150 (Landrace × Large White) crossbred gilts (weighing 149.9 ± 3.1 kg) were fed gestation diets (12.55 MJ of ME/kg) containing SID Lys levels of 0.43, 0.52, 0.60, 0.70 or 0.80% respectively. Gilts were fed 2.0 kg/day from day 1 to 80 and 3.0 kg/day from day 80 to 110 of gestation respectively. Gilts were allocated to treatments based on their body weight on the day of breeding. Weight gain from day 80 to 110 increased with increasing dietary SID Lys levels (p = 0.044). Fitted broken‐line (p = 0.031) and quadratic plot (p = 0.047) analysis of body weight gain indicated that the optimal SID Lys level for primiparous sows was 0.70 and 0.69% respectively. During gestation, neither backfat thickness nor loin eye area was affected by dietary SID Lys level. Increasing dietary Lys had no effect on the litter size at birth or pigs born alive per litter. Litter weight at birth was not affected by dietary SID Lys level. The litter weight variation at birth quadratically decreased with increasing dietary SID Lys (p = 0.021) and was minimized at 0.70% dietary SID Lys. Gilts fed the 0.70% SID Lys diet had the highest dry matter (p = 0.031) and protein (p = 0.044) content in colostrum. On day 110 of gestation, gilts fed the 0.70% SID Lys diet tended to have the highest serum prolactin (p = 0.085) and serum insulin (p = 0.074) levels. The data demonstrate that the optimal dietary SID Lys was 0.70% for pregnant gilts, which is similar to the recommendation of 0.69% that was estimated by the NRC (2012). 相似文献
95.
The influences of ambient temperature and crude protein levels on performance and serum biochemical parameters in broilers 下载免费PDF全文
Q. W. Liu J. H. Feng Z. Chao Y. Chen L. M. Wei F. Wang R. P. Sun M. H. Zhang 《Journal of animal physiology and animal nutrition》2016,100(2):301-308
This study was undertaken to investigate the effects of ambient temperature, crude protein levels and their interaction on performance and serum biochemical parameters of broiler chickens. A total of 216 Arbor Acre broiler chickens (108 males and 108 females) were used in a 2 × 3 factorial arrangement and randomly reared at two temperatures (normal temperature: 23 °C; daily cyclic high temperature: 28–32 °C) and fed on three diets with different crude protein levels (153.3, 183.3 or 213.3 g/kg, with constant essential amino acids) from 28 to 42 days of age. Daily cyclic high ambient temperature decreased final body weight, average daily weight gain, average daily feed intake and serum total protein contents (p < 0.001, p < 0.001, p < 0.001, p = 0.008 respectively), but increased feed/gain, mortality, respiratory rate, rectal temperature, serum uric acid contents and serum creatine kinase activity (p = 0.008, p = 0.003, p < 0.0001, p < 0.0001, p < 0.0001, p = 0.003 respectively), irrespective of crude protein levels. At the ambient temperature, reducing crude protein levels resulted in an increase in feed/gain (p < 0.001), but a decrease in serum total protein and uric acid contents. Only serum creatine kinase activity in broiler chickens was interacted by daily cyclic high ambient temperature and dietary crude protein levels (p = 0.003). These results indicated that daily cyclic high ambient temperature had a great effect on performance and serum biochemical parameters in broiler chickens, whereas dietary crude protein levels affected them partially. 相似文献
96.
1. An experiment was conducted to study the effect of thiram on liver antioxidant capacity and incidence of tibial dyschondroplasia in broilers. 2. One hundred and twenty Avian commercial broilers were allotted at random to three treatments: control group, low thiram group (50 mg/kg) and high thiram group (100 mg/kg). 3. Blood samples were collected to determine the activity of AST (aspartate aminotransferase). At the end of the trial, broilers were killed and liver samples were collected to determine the activity of SOD (superoxide dismutase), GSH-Px (glutathione peroxidase) and MDA (malondialdehyde) content, while the right proximal tibiotarsi were dissected in longitudinal section for assessment of tibial dyschondroplasia (TD) incidence and TD score. 4. The results showed that thiram increased the incidence of TD and TD scores, increased serum AST activity and MDA content of liver, and decreased the activity of SOD and GSH-Px in the liver. 5. They suggest that thiram causes TD in broilers by reducing liver antioxidation capability and damaging liver function; this may be one of the mechanisms by which thiram causes TD in broilers. 相似文献
97.
1. A total of 30 varieties and selection lines of triticale grown under similar conditions were characterised. Thousand grain weight, specific weight, Hagberg falling number and N were 50.2 +/- 5.0 g, 72.4 +/- 2.1 kg/hl, 96 +/- 48 s and 16.1 +/- 0.11 g/kg, respectively. 2. Mean phosphorus (P) concentration was 2.86 +/- 0.31 g/kg, of which 77% was of phytic origin. Mean phytase activity was 1018 +/- 319 phytase units (PU)/kg. A genotypic effect on phytase activity was detected amongst 5 varieties studied out of 30. Potential and real applied viscosities were positively correlated and mean values were 3.53 +/- 0.66 and 2.15 +/- 0.31 ml/g, respectively. 3. The efficacy of plant phytase in improving P availability was assessed in chickens up to 3 weeks of age. Growth performance and bone ash concentration were compared in birds given either a maize (450 g/kg) and soybean meal (230 g/kg) phosphorus deficient diet containing 3.5 g P/kg, this basal diet supplemented with 1 or 2 g P/kg as monocalcium phosphate (MCP) or triticale (450 g/kg) and soybean meal (230 g/kg) diets containing 3.2 to 3.8 g P/kg with no MCP. To achieve graded levels of phytase activity, 4 varieties of triticale, intact or in which phytase was denaturated by heat treatment, were used. Estimated metabolisable energy, protein, amino acids and calcium concentrations were similar in all diets. 4. Phytase activity in the triticale-based diets ranged between 135 and 1390 PU/kg. Growth performance and bone ash were responsive to plant phytase and to MCP. Non-linear models of these responses were adjusted with the best fit for bone ash parameters. The values of 250, 500 and 1000 PU of plant phytase were estimated to be equivalent to 0.46, 0.67 and 0.81 g P as MCP, respectively. 相似文献
98.
Seasonal and photoperiodic regulation of secretion of hormones associated with reproduction in Magang goose ganders 总被引:1,自引:0,他引:1
Shi ZD Huang YM Liu Z Liu Y Li XW Proudman JA Yu RC 《Domestic animal endocrinology》2007,32(3):190-200
This study examined the reproductive endocrine profile under natural and artificial photoperiods in Magang goose ganders. Group 1 ganders (n=8) served as non-treated controls and were exposed to natural photoperiod throughout the experiment from 13th January to 17th December 2004. Group 2 ganders (n=8) were exposed to 18 h long daily photoperiod for 60 days from 13 January till 15 March 2004 and again to 16 h photoperiod for 75 days till 10th October 2004, and the 11h short photoperiod in the remainder periods of the experiment. In control ganders, plasma LH concentrations were high in normal breeding seasons (August-March) and decreased to low levels in non-breeding season from April to July. Testosterone concentrations changed similarly to that of LH throughout the seasons. Seasonal pattern of PRL concentrations was opposite to those of LH and testosterone, with low values in breeding season and high values in non-breeding season. In artificial photoperiod treated ganders, increasing photoperiod increased PRL and decreased LH and testosterone concentrations, while decreasing photoperiod reversed these changes. There were no seasonal or photoperiod caused changes in plasma T3 concentrations in both control ganders and artificial photoperiod treated ganders. These results demonstrated that in Magang goose ganders that long photoperiod stimulates PRL secretion and decreases LH secretion, which terminates reproductive season in spring and early summer, and short photoperiod stimulates LH secretion and inhibits PRL secretion rendering ganders enter into reproductive season. 相似文献
99.
Concept maps have become a ubiquitous tool in education in the last 20 years and are used extensively to teach scientific concepts. A concept map is a tool learners can use to organize information about a topic in terms of key concepts and the relationships among them. As a graphical representation, the map provides an overall picture of a particular concept or topic. This article describes how we have used concept maps to teach physiology to veterinary medical and veterinary technician students enrolled in our on-campus and distance-learning programs. 相似文献
100.
Bani Ismail Z Al-Rukibat R Al-Tarazi Y Al-Zghoul MB 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(2):66-69
Eighteen synovial fluid samples from 11 male dromedarian calves, 9-12 month old, were analysed cytologically and bacteriologically. Calves were lame and all joints were grossly swollen. The mean +/- SD of total nucleated cell count was 7970 +/- 5000 cells/microl (range 2800-20,000 cells/microl). Polymorphonuclear (PMN) leucocytes were the predominant cell type. The mean +/- SD of absolute and percentages of each cell type were as follows: PMN leucocytes 5518 +/- 3600 cells/microl and 68 +/- 19%, monocytes/macrophages 1600 +/- 1120 cells/microl and 26 +/- 17%, lymphocytes 830 +/- 140 cells/microl and 8 +/- 7%, and red blood cell 350 +/- 130 cells/microl. The mean +/- SD of total protein concentration was 3.5 +/- 1 g/dl (range 2.5-5 g/dl). The most commonly isolated bacteria were non-haemolytic streptococci spp., followed by Arcanobacterium pyogenes and Staphylococcus aureus. No bacterial growth was obtained in eight samples and non-revealed Mycoplasma spp. 相似文献