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61.
Halimeh Mobarak Ezzatollah Fathi Raheleh Farahzadi Nosratollah Zarghami Sara Javanmardi 《Veterinary research communications》2017,41(1):41-47
Mesenchymal stem cells are undifferentiated cells that have the ability to divide continuously and tissue regeneration potential during the transplantation. Aging and loss of cell survival, is one of the main problems in cell therapy. Since the production of free radicals in the aging process is effective, the use of antioxidant compounds can help in scavenging free radicals and prevent the aging of cells. The aim of this study is evaluate the effects of L-carnitine (LC) on proliferation and aging of rat adipose tissue-derived mesenchymal stem cells (rADSC). rADSCs were isolated from inguinal region of 5 male Rattus rats. Oil red-O, alizarin red-S and toluidine blue staining were performed to evaluate the adipogenic, osteogenic and chondrogenic differentiation of rADSCs, respectively. Flow cytometric analysis was done for investigating the cell surface markers. The methyl thiazol tetrazolium (MTT) method was used to determine the cell proliferation of rADSCs following exposure to different concentrations of LC. rADSCs aging was evaluated by beta-galactosidase staining. The results showed significant proliferation of rADSCs 48 h after treatment with concentrations of 0.2 mM LC. In addition, in the presence of 0.2 mM LC, rADSCs appeared to be growing faster than control group and 0.2 mM LC supplementation could significantly decrease the population doubling time and aging of rADSCs. It seems that LC would be a good antioxidant to improve lifespan of rADSCs due to the decrease in aging. 相似文献
62.
Evi Pecceu Brittainy Stebbing Yolanda Martinez Pereira Ian Handel Geoff Culshaw Hannah Hodgkiss-Geere Jessica Lawrence 《Veterinary research communications》2017,41(4):249-256
Vasovagal tonus index (VVTI) is an indirect measure of heart rate variability and may serve as a marker of disease severity. Higher heart rate variability has predicted lower tumour burden and improved survival in humans with various tumour types. The purpose of this pilot study was to evaluate VVTI as a biomarker of remission status in canine lymphoma. The primary hypothesis was that VVTI would be increased in dogs in remission compared to dogs out of remission. Twenty-seven dogs were prospectively enrolled if they had a diagnosis of intermediate to high-grade lymphoma and underwent multidrug chemotherapy. Serial electrocardiogram data were collected under standard conditions and relationships between VVTI, remission status and other clinical variables were evaluated. VVTI from dogs in remission (partial or complete) did not differ from dogs with fulminant lymphoma (naive or at time of relapse). Dogs in partial remission had higher VVTI than dogs in complete remission (p = 0.021). Higher baseline VVTI was associated with higher subsequent scores (p < 0.001). VVTI also correlated with anxiety level (p = 0.03). Based on this pilot study, VVTI did not hold any obvious promise as a useful clinical biomarker of remission status. Further investigation may better elucidate the clinical and prognostic utility of VVTI in dogs with lymphoma. 相似文献
63.
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
64.
The present study was carried out to investigate the pattern of apoptosis in the healthy antral and atretic follicles of Philippine swamp buffaloes (BU) in comparison with Holstein-Friesian (HF) cows. Paraffin sections of healthy follicles and various stages of atretic follicles were stained using the terminal deoxynucleotidyl transferase (TdT)-mediated biotinylated deoxyuridine triphosphates (dUTP) nick end-labelling (TUNEL) method to detect DNA fragmentation and cleaved caspase-3 antibody to detect cells committed to undergo apoptosis. Five equidistant areas of a follicle were counted for the presence of TUNEL- and caspase-3-positive cells. Healthy follicles of BU and HF contained no TUNEL-positive cells in the granulosa and theca layer but showed some caspase-3 positivity. The granulosa layer of advanced atretic follicles showed a significantly higher frequency of caspase-3 positivity than the healthy and early atretic follicles in both breeds. The frequency of caspase-3-positive cells of BU was significantly higher than HF in the granulosa layer of healthy, early atretic and advanced atretic follicles. In the theca interna layer, BU and HF showed a significantly lower and higher frequency of TUNEL-positive cells in the late atretic follicles compared with advanced atretic follicle, respectively. However, the frequency of caspase-3-positive cells of both BU and HF in the late atretic follicles was significantly higher than the advanced atretic follicles in the theca interna layer. These results indicate that caspase-3 and DNA fragmentation is involved in the buffalo ovarian apoptotic process. 相似文献
65.
Ghanem ME Nishibori M Nakao T Nakatani K Akita M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(7):713-715
Factor XI deficiency is an autosomal recessive coagulopathy in Holstein cattle. Affected cows have a tendency to show repeat breeding. Forty repeat breeding Holstein Friesian cows were selected and tested for the Factor XI mutation. Genomic DNA was isolated from the blood of the cows (n=40). Exon 12 of the Factor XI gene of the cows was amplified by PCR. One repeat breeding cow was heterozygous to the Factor XI mutation as indicated by the presence of two DNA fragments of 320 bp and 244 bp. The insertion of the 76 bp in the heterozygous cow was confirmed by DNA sequencing. The heterozygous cow was in her fourth lactation. She gave birth to male twins at the last calving. She was inseminated artificially four times after the last calving. Factor XI deficiency in cattle has been reported in different countries. However, no case was reported in Japan. This might be the first to report Factor XI mutation in Holstein cattle in Japan. 相似文献
66.
This study was designed to clarify the characteristics of changes in plasma concentrations of reproductive hormones in heifers from birth to puberty. Weekly or daily hormonal changes were observed in 39 heifers. Daily changes in the concentration of follicle-stimulating hormone (FSH) demonstrated a consistent cycle of hormone changes over a 7- to 8-day period in heifers from approximately 10 days to 9 months old. Weekly changes in reproductive hormones showed that there were three brief periods in heifers between birth and puberty in which dramatic changes occur. The first period was the first week after birth, during which a reciprocal relationship between steroid hormones and gonadotropins was observed. At birth, the concentrations of steroid hormones were higher than those at any other age. These hormone levels rapidly decreased within the first week after birth. Gonadotropin levels, however, increased from birth to 1 week of age. The second period of major change was at approximately 4 weeks of age when there was an increase in the concentrations of luteinizing hormone (LH), estradiol-17beta, testosterone, and immunoreactive inhibin. The third period was the last 5 weeks before the first ovulation, when there was an increase in the concentrations of estradiol-17beta followed by an increase in (LH). These results suggest that regular hormone changes start from 10 days after birth and that the periods from birth to 4 weeks of age and the last 5 weeks before the first ovulation in heifers are important to the development of reproductive functions before puberty. 相似文献
67.
The objective of this study was to analyse the effects of different levels of rumen-degradable protein (RDP) on intake, digestibility
and microbial protein synthesis by supplementing mustard oil cake (MOC) on rice straw-based diet of cattle (Bos indicus) in Bangladesh. A 4 × 4 Latin square design was applied. Four diets having constant energy (7.0 MJ/kg of dry matter (DM))
with varying levels of RDP (M
0 = 4.1 g/MJ (control), M
1 = 6.3 g/MJ, M
2 = 8.3 g/MJ and M
3 = 12.4 g/MJ of metabolizable energy (ME)) were received by each animal for a period of 28 days. A metabolism trial was conducted
for 7 days. Results indicate that with increasing levels of RDP, crude protein (CP) and RDP intake increased significantly
(P < 0.01). The significant (P < 0.01) increase in digestibility values are obtained for DM, organic matter, CP and digestible organic matter in the rumen.
The digestibility of neutral detergent fibre and acid detergent fibre was also increased significantly (P < 0.05). The total nitrogen (N), ammonia-N and total volatile fatty acids increase significantly (P < 0.01) while the rumen pH increased from M
0 to M
2 and decreased thereafter. The efficiency microbial N intake increased significantly (P < 0.01) but showed a curvilinear response with higher RDP level (12.40 g/RDP/MJ ME). This study concludes that supplementation
of RDP from MOC enhances the intake, digestibility and microbial protein synthesis which ultimately increases utilization
of low-quality feed resources that can be used for developing cost-effective feeding systems on a straw-based diet in tropical
regions. 相似文献
68.
Indigenous chicken (IC) and their production systems were characterized to understand how the whole system operates for purposes
of identifying threats and opportunities for holistic improvement. A survey involving 594 households was conducted in six
counties with the highest population of IC in Kenya using structured questionnaires. Data on IC farmers’ management practices
were collected and analysed and inbreeding levels calculated based on the effective population size. Indigenous chicken were
ranked highest as a source of livestock income by households in medium- to high-potential agricultural areas, but trailed
goats in arid and semi-arid areas. The production system practised was mainly low-input and small-scale free range, with mean
flock size of 22.40 chickens per household. The mean effective population size was 16.02, translating to high levels of inbreeding
(3.12%). Provision for food and cash income were the main reasons for raising IC, whilst high mortality due to diseases, poor
nutrition, housing and marketing channels were the major constraints faced by farmers. Management strategies targeting improved
healthcare, nutrition and housing require urgent mitigation measures, whilst rural access road network needs to be developed
for ease of market accessibility. Sustainable genetic improvement programmes that account for farmers’ multiple objectives,
market requirements and the production circumstances should be developed for a full realization of IC productivity. 相似文献
69.
A study was undertaken from October 2006 to March 2007 to determine the prevalence and antimicrobial resistance patterns of Salmonella serovars. Liver, mesenteric lymph nodes, intestinal content, and carcass swab samples (each n?=?186) were collected from 186 apparently healthy slaughtered cattle at Bahir Dar abattoir. Bacteriological analysis was done according to the International Organization for Standardization (ISO 6579 2002). Isolates were serotyped at Agence Française de Securite Sanitaire des Aliments, Cedex, France. Twenty-eight isolates consisting of Salmonella Typhimurium, Salmonella Newport, Salmonella Haifa, Salmonella Heidelberg, Salmonella Infantis, and Salmonella Mishmarhaemek were identified. Salmonella Typhimurium and Salmonella Newport were most frequently isolated while Salmonella Heidelberg and Salmonella Mishmarhaemek were isolated least. Eleven of the 28 (39.3%) were resistant to one or more of the antimicrobials tested. Resistance was shown to ampicillin, chloramphenicol, gentamycin, norfloxacin, polymyxin-B, streptomycin, tetracycline, and trimethoprim. Four of 11 (36.4%) were multiple antimicrobial resistant. All the isolates tested were susceptible to the antimicrobial effects of gentamycin, norfloxacin, and trimethoprim. Eleven, four, and two isolates of the 28 were resistant to streptomycin, tetracycline, and ampicillin, respectively. All isolates of Salmonella Infantis, Salmonella Typhimurium (except one), and Salmonella Mishmarhaemek were susceptible to the tested antimicrobials. One Typhimurium isolate was resistant to chloramphenicol, streptomycin, and tetracycline. Salmonella Haifa was multiply antimicrobial resistant to ampicillin, tetracycline, and streptomycin. All isolates of Salmonella Heidelberg were resistant to streptomycin. Results of this study indicated high level of carcass contamination with antimicrobial-resistant Salmonella serovars which could pose public health risk; suggests need for hygienic slaughtering operations and proper cooking of meat before consumption. Further detailed studies involving different abattoirs, animal products, food items, and animals on different settings were recommended in the study area. 相似文献
70.
Mahr-un-Nisa Shahzad MA Phillips CJ Sarwar M 《Tropical animal health and production》2012,44(5):947-952
Urea is a common ingredient of the diets of intensively fed lambs, but is increasingly required for industrial processes.
Maize steep liquor (MSL) is a by-product of maize grain degradation to produce starch that may be a suitable replacement.
Fifty growing lambs were fed on equinitrogenous diets in which between 0% and 80% of the urea was replaced by MSL; their growth
and metabolism were recorded over 70 days. Increasing replacement of urea by MSL increased feed intake and nutrient digestibilities,
leading to increased growth rates, more efficient feed conversion, and increased nitrogen retention. Concentrations of triiodothyroxin,
thyroxin, glucose, and methionine were increased by replacement of urea by liquor, and plasma urea was reduced. This study
suggests that MSL is a suitable replacement for up to 80% of urea in the diet of rapidly growing lambs. 相似文献