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81.
M. Ahmadi W. J. Wiebold J. E. Beuerlein K. D. Kephart 《Journal of plant nutrition》2013,36(7):1471-1481
Corn (Zea mays L.) is an important source of protein for humans and animals. Because dent corn is highly responsive to nitrogen (N) fertilization, substantial amounts of N are used for corn production. Application of N fertilizer may reduce protein quality of corn kernels through an increase in zein content. The objective of this study was to determine if corn endosperm characteristics influence the effect of N fertilization on protein quality. In 1988, six corn hybrids differing for endosperm characteristics were grown at two locations in Ohio and with two N rates, 34 and 200 kg/ha. The waxy hybrid had a greater concentration of fraction I protein than the non‐wary hybrid. These two hybrids did not differ for other fractions except fraction III at Columbus. The soft endosperm hybrid had a higher concentration of fraction I protein than the hard endosperms hybrids. Soft and hard endosperm hybrids differed for fraction II protein for the 34 kg N/ha fertilizer rate but not the 200 kg N/ha fertilizer rate. These two classes of hybrids did not differ for fraction III protein. Increasing N fertilizer increased fraction II concentration for all hybrids. Concentrations of the other two protein fractions did not respond to fertilizer rate. The increase in fraction II concentration with N fertilization may result in a decrease of protem quality and feed value. Although all hybrids responded to N fertilizer, some hybrids had bigger increases in fraction II proteins than other hybrids. 相似文献
82.
Nasser Vesal Mohammadrahim Ahmadi Mehrzad Foroud Hadi Imani 《Veterinary anaesthesia and analgesia》2013,40(3):328-332
ObjectiveTo evaluate the anti-nociceptive effects of lidocaine, lidocaine-bupivacaine combination or bupivacaine following caudal epidural administration in cows undergoing reproductive procedures.Study designBlinded, randomized experimental study.AnimalsThirty seven healthy Holstein cows (mean weight ± SD, 633 ± 41 kg).MethodsAnimals were allocated randomly to receive one of four treatments: group LID, 0.2 mg kg?1 lidocaine 2%; group LID-BUP, lidocaine-bupivacaine mixture in a 1:1 volume ratio (0.1 mg kg?1 and 0.025 mg kg?1, respectively); group BUP-LD, 0.05 mg kg?1 bupivacaine 0.5%; and group BUP-HD, 0.06 mg kg?1 bupivacaine 0.5%. The onset and duration of perineal anti-nociception were determined using superficial and deep pin pricks and the number of cows with complete perineal anti-nociception was recorded. Parameters were compared using anova followed by Duncan's test where relevant.ResultsMean ± SD time to onset of anti-nociception following epidural administration of BUP-LD was significantly longer than for LID-BUP (p < 0.05). The duration (in minutes) of perineal anti-nociception was significantly longer following epidural administration of BUP-HD (247 ± 31) versus LID-BUP (181 ± 33) and LID (127 ± 25) minutes respectively. The % of cows with complete anti-nociception was increased in the group treated with BUP-HD compared to BUP-LD. Severe ataxia or recumbency did not occur in any groups.Conclusions and clinical relevanceEpidurally administered bupivacaine, at a dose of 0.06 mg kg?1, may provide satisfactory caudal epidural anti-nociception for longer-duration obstetric and surgical procedures. 相似文献
83.
Yasin Bagheri Zahra Keshtmand Reza Rahbarghazi Mehrdad N. Gharamaleki Alireza Barati Sara Bagheri Jafar Rezaie Aysa Rezabakhsh Mahdi Ahmadi Masoud Delashoub 《Animal Science Journal》2020,91(1)
This study was conducted to evaluate the Salvia officinalis hydroalcoholic extract on fertility capacity and behavioral features in rats exposed to immobilization stress. Male rats were randomly divided into five groups; Control; Stressed rats; and Stressed rats received 50, 100 and/or 200 mg/kg bw S. officinalis hydroalcoholic extract. To induce stress, rats were immobilized for 49 days and received S. officinalis extract orally. On day 56, we analyzed behavioral tests and evaluated reproduction capacity by measuring LH, FSH, and testosterone. Sperm parameters such as motility, viability, and total count were also determined. Bodyweight changes were also calculated on day 56. Male rats from different groups were mated with healthy female rats. Data showed that the use of 100 and 200 mg/kg bw S. officinalis extract in stressed rats increased bodyweight gain and improved behavioral disorders compared to control‐matched groups (p < .05). Besides, administration of 100 and 200 mg/kg bw S. officinalis extract had the potential to improve sperm parameters and fertility capacity in stressed rats (p < .05). Decreased testosterone levels were blunted in the stressed rats that received plant extract coincided with the reduction of LH and FSH compared to control‐matched stressed rats (p < .05). We found neutral effects in stressed rats that received 50 mg/kg bw plant extract. Collectively, the hydroalcoholic extract of S. officinalis could improve the fertility capacity and behavioral features under stressful conditions in a dose‐dependent manner. 相似文献
84.
Behnam Abbaspour Seyed Davood Sharifi Shokoufe Ghazanfari Abdollah Mohammadi-Sangcheshmeh Shirin Honarbakhsh 《Reproduction in domestic animals》2020,55(5):594-603
The objective of this study was to evaluate the effect of dietary supplementation of whole flaxseed on sperm traits and sperm fatty acid profile in aged broiler breeder roosters. Twelve Ross 308 broiler breeder roosters (age: 52 weeks; weight: 4,900 ± 210 g) haphazardly allotted to three dietary treatments (each treatment contained four replicates and one bird in each replicate) for six weeks. Treatments were different levels of flaxseed (0% flaxseed [GFL0], 2% flaxseed [GFL2] and 4% flaxseed [GFL4]). The feed intake quadratically decreased (p < .05) with increasing whole flaxseed levels for the period (58 to 60 weeks). Sperm traits (semen volume and sperm concentration, sperm total and forward motility, sperm viability and morphology, sperm plasma membrane functionality) were evaluated every two weeks (four times), and sperm fatty acid profile was assessed at the end of the experiment. Semen volume, sperm concentration and sperm morphology were not affected by treatments. On week 60, GFL2 group showed a significantly lower percentage of total and progressive sperm motility and sperm membrane functionality in comparison with the control and GFL4 groups. Also, sperm viability was lower in GFL2 group compared with other groups on week 58 (p < .05). In terms of sperm fatty acid profile, GFL2 group significantly reduced the percentage of linoleic acid (C18:2 [n-6]) in comparison with other groups. However, any of the other fatty acids were not affected by dietary flaxseed. In conclusion, dietary supplementation of whole flaxseed could not improve the quality of aged broiler breeder roosters' sperm in this study, nor it could alter the sperm fatty acid profile; thus, it seems necessary to use some antioxidants such as vitamin E in the diet of aged broiler breeder roosters, when supplementing the diets with oils or oilseeds such as flaxseed. 相似文献
85.
Ahmadi Fackjouri H Falahatkar B Ershad Langroudi H 《Journal of animal physiology and animal nutrition》2011,95(5):632-641
In order to improve feeding and growth of juvenile great sturgeon Huso huso, the effects of various lipid sources in feed were examined. Three hundred juveniles (initial body weight 215 ± 10 g) were distributed into 15 flow-through 1100 l tanks (20 fish per tank). Five experimental diets containing various lipid levels were formulated: diet C (control; without added oil), SO(L) and SO(H) diets containing soybean oil concentrations respectively, (53.5 vs. 174 g/kg), FO(L) and FO(H) diets containing fish oil with low and high concentrations respectively (53.5 vs. 174 g/kg). Fish were fed three times daily based on their appetite for a period of 6 weeks. At the termination of the experiment, growth rate was improved with increasing oil content in the diets. There were significant differences in final weights among fish fed the different experimental diets. Lipid content of muscle and liver significantly increased with increasing dietary lipid levels for both soybean and fish oil. The lowest cholesterol level and the highest haematocrit value were measured in fish fed the FO(H) diet. No significant difference was found among dietary treatments in terms of triacylglycerol concentration, number of red blood cell, mean corpuscular volume, mean corpuscular haemoglobin (MCH) and MCH concentration (MCHC). According to the most growth indices, results of this study suggest that the best results were observed in FO(H) which can be attributed to the greater palatability of diet containing high fish oil, supply of fatty acid requirement and enhanced physiological performance. 相似文献
86.
Ahmadi S Muth-Selbach U Lauterbach A Lipfert P Neuhuber WL Zeilhofer HU 《Science (New York, N.Y.)》2003,300(5628):2094-2097
In the mammalian CNS, N-methyl-D-aspartate (NMDA) receptors serve prominent roles in many physiological and pathophysiological processes including pain transmission. For full activation, NMDA receptors require the binding of glycine. It is not known whether the brain uses changes in extracellular glycine to modulate synaptic NMDA responses. Here, we show that synaptically released glycine facilitates NMDA receptor currents in the superficial dorsal horn, an area critically involved in pain processing. During high presynaptic activity, glycine released from inhibitory interneurons escapes the synaptic cleft and reaches nearby NMDA receptors by so-called spillover. In vivo, this process may contribute to the development of inflammatory hyperalgesia. 相似文献
87.
The anaphase-promoting complex (APC) is highly expressed in postmitotic neurons, but its function in the nervous system was previously unknown. We report that the inhibition of Cdh1-APC in primary neurons specifically enhanced axonal growth. Cdh1 knockdown in cerebellar slice overlay assays and in the developing rat cerebellum in vivo revealed cell-autonomous abnormalities in layer-specific growth of granule neuron axons and parallel fiber patterning. Cdh1 RNA interference in neurons was also found to override the inhibitory influence of myelin on axonal growth. Thus, Cdh1-APC appears to play a role in regulating axonal growth and patterning in the developing brain that may also limit the growth of injured axons in the adult brain. 相似文献
88.
Post‐partum period has an important role in cows' breeding due to its effects on reproductive efficiency and subsequent pregnancy. Escherichia coli, Trueperella pyogenes (Arcanobacterium pyogenes), Fusobacterium necrophorum and Prevotella melaninogenicus are recognized as major pathogens associated with uterine endometrial lesions. The objective of this study was to identify these pathogens using the polymerase chain reaction (PCR) as a culture‐independent sensitive method. A total of 172 cows were examined 25–35 days post‐partum, and 128 cows were examined at 2 weeks later (39–49 days post‐partum). Uterine discharges were collected by covered plastic infusion pipettes. The prevalence of endometritis was greater in the first examination than the second (35.5% vs. 16%). E. coli was detected in eight of the samples, T. pyogenes was detected in 13 of the samples and F. necrophorum was detected in 11 of the samples. There was no positive sample of P. melaninogenicus. Uterine contamination by T. pyogenes and F. necrophorum in the first examination was higher than the second examination. T. pyogenes affected as a tendency the prevalence of clinical endometritis in first examination. Primiparous cows showed 4.02 times higher odds of clinical endometritis compared with second‐parity cows in first examination. A multiplex PCR protocol as a simple, less expensive, fast assay was introduced to identify E. coli, T. pyogenes and F. necrophorum. 相似文献
89.
Babak Baharvand Mansour Esmailidehaj Jamileh Alihosaini Shirin Bajoovand Saeedeh Esmailidehaj Zeynab Hafizibarjin 《Iranian Biomedical Journal》2016,20(1):41-48
Background:
This study was conducted to reveal that whether i.v. injection of oleuropein, the most potent polyphenolic antioxidant in olive leaf, has any effect on the magnitude of reperfusion arrhythmia in anesthetized rats or not.Methods:
Eighty male Wistar rats were divided into 8 groups of 10 each: groups 1 and 5 were assigned as the prophylactic and treatment control groups, groups 2 and 6 as the prophylactic and treatment groups with lidocaine (10 mg/kg), groups 3 and 4 as the prophylactic groups with 10 and 50 mg/kg oleuropein (i.v.), and groups 7 and 8 as the treatment groups with 10 and 50 mg/kg oleuropein (i.v.), respectively. Reperfusion injury was induced by 5-min regional ischemia and 15-min reperfusion of left anterior descending coronary artery. Heart rate, blood pressure, and electrocardiogram were monitored throughout the procedure.Results:
blood pressure was significantly decreased by infusion of 50 mg/kg oleuropein in groups 4 and 8, but unlike the lidocaine as a standard anti-arrhythmic drug in groups 2 and 5 had not significant effect on heart rate. The onset of arrhythmia in groups received oleuropein (groups 3, 4, 7, and 8) was significantly delayed. The mortality rate due to irreversible ventricular fibrillation was also significantly reduced in groups 3, 4, 7, and 8. The effect of lidocaine in groups 2 and 5 was more potent than that in oleuropein group.Conclusion:
These findings indicate that i.v. injection of oleuropein possibly through its antioxidant activity reduces the magnitude of reperfusion-induced arrhythmia.Key Words: Oleuropein, Arrhythmia, Reperfusion, Rats 相似文献90.
Background
: The emergence and propagation of different phylogenetic groups of antimicrobial-resistant E. coli have become a worldwide health concern in human and veterinary medicine. Therefore, the evaluation of the phylogenetic distribution of antibiotic-resistant E. coli is important for therapeutic and economic purposes. The aims of this study were to determine phylogenetic groups and patterns of antibiotic resistance of E. coli strains isolated from human urinary tract infection and avian colibacillosis. Methods: A total of 50 E. coli isolates (25 from human urinary tract infection and 25 from avian colibacillosis) were characterized by culture and assigned as different phylogenetic groups (A, B1, B2, and D) by triplex PCR assay. Kirby-Bauer disk diffusion method was used to assess the susceptibility of all isolates to ten antibiotics. Results: Results showed that the majority of the human and poultry isolates belonged to phylogenetic groups A and B2 and phylogenetic group B1 of the avian pathogenic strain isolates were the most drug-resistant isolates. Most of the isolates were resistant to at least five antibiotics, and multiple drug resistance was observed in 98% of E. coli isolates. A high degree of resistance was seen against penicillin and erythromycin. Conclusion: According to the results of this study, multidrug-resistance among isolates and high relation between phylogenetic groups and resistance in both human and poultry isolates were observed. Key Words: Escherichia coli, Avian colibacillosis, Phylogenetic grouping 相似文献