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1.
Evaluating the Effects of Dietary Prebiotic Mixture of Mannan Oligosaccharide and Poly‐β‐Hydroxybutyrate on the Growth Performance,Immunity, and Survival of Rainbow Trout,Oncorhynchus mykiss (Walbaum 1792), Fingerlings
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Ebrahim H. Najdegerami Amir Tokmachi Farideh Bakhshi 《Journal of the World Aquaculture Society》2017,48(3):415-425
This study investigated the effects of dietary poly‐β‐hydroxybutyrate (PHB) and mannan oligosaccharide (MOS) on the growth performance, digestive enzyme activities, and disease resistance of rainbow trout fingerlings. A total of 420 fingerlings, distributed equally into four different groups, each with three replicates, were fed a basal diet (control), 2% PHB (PHB), 0.2% MOS (MOS), or a diet supplemented with a mixture of 2% PHB and 0.2% MOS (PHB+MOS) for 60 d. Results showed that dietary PHB and/or MOS did not cause significant improvement in the growth performance of the fingerlings. The gut pH was markedly reduced; however, the activities of the digestive enzymes (except for pepsin and amylase by dietary PHB) were not significantly improved by the dietary supplements. Results also showed that dietary PHB and/or MOS markedly increased the resistance of the fingerlings toward Yersinia ruckeri infection, while the lowest total antibody was observed in fish fed control and MOS, indicating that MOS exerts its protective effects by modulating other mechanisms. Overall, this study provided a first screening effort to determine the effects of PHB and/or MOS as dietary supplements in rainbow trout fingerlings to develop an optimal prebiotic mix for improving the growth and health status of rainbow trout. 相似文献
2.
Efficacy of essential oils combination on performance,ileal bacterial counts,intestinal histology and immunocompetence of laying hens fed alternative lipid sources
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Asma Mousavi Amir Hossein Mahdavi Ahmad Riasi Masoud Soltani‐Ghombavani 《Journal of animal physiology and animal nutrition》2018,102(5):1245-1256
This study was carried out to assess the effects of a blend of herbal essential oils (namely Thymus vulgaris, Mentha piperita, Rosmarinus offisinalis and Anethum graveolens) and different dietary lipid sources on the performance, ileal bacterial enumeration, intestinal histological alterations and immune responses in laying hens. For this purpose, a total of 150 laying hens were randomly allocated to six experimental treatments with five replicates of five birds each. Dietary treatments consisted of three levels of a mixture of essential oils (0, 100 and 200 mg/kg) and two sources of lipid (soybean oil and fish oil containing different ratios of n‐6 to n‐3 fatty acids) fed to the animals during an 80‐days feeding trial. Findings indicated that dietary administration of fish oil not only increased significantly the spleen relative weight (p < 0.01) and the antibody titre against Newcastle virus (p < 0.05) but also led to reductions in liver relative weight (p < 0.05) and feed conversion ratio (p < 0.05). Moreover, the mixture of herbal essential oils brought about declines in hepatic relative weight, heterophile to lymphocyte ratio (p < 0.05) and intestinal pathogen populations (p < 0.01). Mention must also be made of the improvements it made in spleen weight (p < 0.01), antibody titres against SRBC (p < 0.01) and Newcastle virus (p < 0.05), villus height to crypt depth ratio (p < 0.01), goblet cell numbers (p < 0.05), lamina propria lymphatic follicle diameters (p < 0.01) and feed conversion ratio (p = 0.06). It may be claimed that the enhancements observed in the performance of laying hens fed fish oil and 200 mg/kg of the blend of essential oils could have potentially been associated with improved intestinal health indices as well as cellular and humoral immune responses. 相似文献
3.
Masoumeh Shahnazari Razieh Bigdeli Aziz Dashbolaghi Reza Ahangari Cohan Alireza Shoari Hossein Hosseini Davoud Nouri Inanlou Vahid Asgary 《Iranian Biomedical Journal》2022,26(4):279
Background: One of the most widely used anticancer agents is microbial L-ASNase. Herein, we assessed the biochemical and biological properties of an isolated L-ASNase from a Gram-negative bacteria strain, Escherichia coli MF-107. Methods:Using garden asparagus, we obtained several bacterial isolates. These strains were further screened for L-ASNase activity. A promising bacterial isolate was selected for L-ASNase production and subsequent purification. The molecular weight of purified L-ASNase was determined. The MTT assay was applied to assess the cytotoxic effect of the purified enzyme. Also, for caspase activity determination and the apoptotic effect of purified enzyme on in cells, we conducted a real-time PCR method. Results:The molecular weight of the enzyme was approximately 37 kDa. In the pH range of 7.5 to 8, the enzyme had considerable stability. At 35 °C, the purified L-ASNase optimum activity was recorded. The cytotoxic effect of the enzyme on treated cells was dose-dependent with an IC50 value of 5.7 IU/ml. The Bax gene expression considerably raised by 5.75-fold (p < 0.001) upon L-ASNase treatment. On the other hand, the anti-apoptotic Bcl-2 gene expression showed a 2.63-fold increase compared to the control (p < 0.05). It was detected that the mRNA levels of caspase-3 and p53 were considerably upregulated (5.93 and 1.85-fold, respectively). We did not find any alternation in the caspase-8 activity of the treated cells compared to untreated cells. Conclusion:In this research, the proliferation of the breast cancer cells remarkably inhibited via the cytotoxic effect of isolated L-ASNase from microbial sources.Key Words: Apoptosis, Breast cancer, Escherichia coli, MCF7 cell line 相似文献
4.
Gholamreza Barzegar Ehsan Ahmadpour Bahador Shahriari Rahmat Solgi Mohammad Hossein Motazedian 《Iranian Biomedical Journal》2022,26(5):374
Background: Cryptosporidium parvum is an important coccidian parasite infecting many mammals, including human. This parasite can manifest as chronic severe diarrhea in immunocompromised individuals, especially those with AIDS. The present study reports the recombinant production of rP2 and rP23 antigens of C. parvum as antigens for detecting human cryptosporidiosis using indirect ELISA tests. Methods:The coding sequences of rP2 and rP23 proteins were codon-optimized, commercially synthesized and sub-cloned in the pET28a expression vector. The expressed proteins were purified by Ni-NTA column chromatography and confirmed by Western blotting. The efficacy of rP2/rP23 proteins for serodiagnosis was evaluated by positive (n = 20) and negative (n = 20) human sera, confirmed by the Ziehl-Neelsen staining as the gold standard test. Results:In ELISA test, the sera from C. parvum-infected patients reacted strongly to rP2/rP23. The sensitivity and specificity related to the diagnostic potential of rP2/rP23 in the ELISA assay were 100%. Conclusion:Our results showed that combination of rP23 and rP2 antigens in ELISA significantly increases the performance of C. parvum serodiagnosis in human cryptosporidiosis. Key Words: Cryptosporidiosis, Enzyme-Linked Immunosorbent Assay, Western blotting 相似文献
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7.
Julia Devos Amir Behrouzi Francois Paradis Christina Straathof Changxi Li Marcos Colazo Hushton Block Carolyn Fitzsimmons 《Journal of animal science》2021,99(5)
Discovery of epigenetic modifications associated with feed efficiency or other economically important traits would increase our understanding of the molecular mechanisms underlying these traits. In combination with known genetic markers, this would provide opportunity to improve genomic selection accuracy in cattle breeding programs. It would also allow cattle to be managed to improve favorable gene expression. The objective of this study was to identify variation in DNA methylation between beef cattle of differential pre-natal nutrition and divergent genetic potential for residual feed intake (RFI). Purebred Angus offspring with the genetic potential for either high (HRFI) or low (LRFI) RFI were prenatally exposed to either a restricted maternal diet of 0.5 kg/d average daily gain (ADG) or a moderate maternal diet of 0.7 kg/d ADG from 30 to 150 d of gestation. We performed DNA methylation analysis of differentially methylated regions (DMR) of imprinted genes (Insulin-like growth factor 2 (IGF2) DMR2, IGF2/H19 imprinting control region (ICR) and IGF2 receptor (IGF2R) DMR2) using post-natal samples of longissimus dorsi (LD) muscle taken from male and female calves at birth and weaning, and of LD muscle, semimembranosus (SM) muscle, and liver samples collected from steers at slaughter (17 months of age). Interestingly, for all three DMR investigated in liver, LRFI steers had higher levels of methylation than HRFI steers. In LD muscle, IGF2/H19 ICR methylation differences for heifers at birth were due to pre-natal diet, while for steers at birth they were mostly the result of genetic potential for RFI with LRFI steers again having higher levels of methylation than HRFI steers. While results from repeated measures analysis of DNA methylation in steers grouped by RFI revealed few differences, in steers grouped by diet, we found higher methylation levels of IGF2 DMR2 and IGF2R DMR2 in LD muscle of restricted diet steers at weaning and slaughter than at birth, as well as increased methylation in LD muscle of restricted diet steers compared with moderate diet steers at weaning and/or slaughter. Our results suggest that differential pre-natal nutrition, and divergent genetic potential for RFI, induces tissue- and sex-specific alterations in post-natal IGF2 and IGF2R methylation patterns and that these patterns can vary with age in Angus beef cattle. 相似文献
8.
Amir Atabak Ronaghinia Nanett Kvist Nikolaisen Stine Green Hansen Helle Harding Poulsen Henrik Lauritz Frandsen Tina Struve Pierre‐Louis Toutain Peter Damborg 《Journal of veterinary pharmacology and therapeutics》2021,44(1):93-106
Antimicrobial agents are used extensively off‐label in mink, as almost no agents are registered for this animal species. Pharmacokinetic (PK) and pharmacodynamic (PD) data are required to determine antimicrobial dosages specifically targeting mink bacterial pathogens. The aims of this study were to assess, in a PKPD framework, the empirical dosage regimen for a combination of trimethoprim (TMP) and sulfadiazine (SDZ) in mink, and secondarily to produce data for future setting of clinical breakpoints. TMP and SDZ PK parameters were obtained experimentally in 22 minks following IV or oral administration of TMP/SDZ (30 mg/kg, i.e. 5 mg/kg TMP and 25 mg/kg SDZ). fAUC/MIC with a target value of 24 hr was selected as the PKPD index predictive of TMP/SDZ efficacy. Using a modeling approach, PKPD cutoffs for TMP and SDZ were determined as 0.062 and 16 mg/L, respectively. By incorporating an anticipated potentiation effect of SDZ on TMP against Escherichia coli and Staphylococcus delphini, the PKPD cutoff of TMP was revised to 0.312 mg/L, which is above the tentative epidemiological cutoffs (TECOFF) for these species. The current empirical TMP/SDZ dosage regimen (30 mg/kg, PO, once daily) therefore appears adequate for treatment of wild‐type E. coli and S. delphini infections in mink. 相似文献
9.
Abbas Rajaeerad Gholam R. Ghorbani Mohammad Khorvash Ali Sadeghi-Sefidmazgi Amir H. Mahdavi Mirja R. Wilkens 《Journal of animal physiology and animal nutrition》2021,105(1):14-25
This study investigated the effects of low potassium diets with different levels of Ca compared to two diets low in dietary cation–anion difference (DCAD) fed prepartum as a strategy to prevent hypocalcemia on sorting behaviour, total tract digestibility, oxidative status and energy and protein metabolism of transition cows. Forty-eight pregnant dairy cows were assigned to 4 treatment groups: Low Ca, low K (LCLK), High Ca, low K (HCLK), Supplementation with anionic mineral mixture (AMS) supplementation with SoyChlor (CAS). After parturition, all animals were fed a standard postpartum diet. Data were collected until 21 DIM. Prepartum urinary pH was significantly reduced by the low DCAD diets, while postpartum Ca homeostasis was affected by the HCLK ration. Feeding AMS induced sorting against particles <1.18 mm in favour of particles >19 mm prepartum. In contrast, cows fed CAS showed an increase in selective consumption of fine particles and sorted against longer particles similar to the HCLK and LCLK groups. Postpartum sorting activity was not affected by the dietary treatments. After calving, apparent digestibility of NDF was significantly reduced in the HCLK group. Prepartum, we observed effects on serum concentrations of non-esterified fatty acids were higher and insulin sensitivity was lower in the AMS group. Blood urea nitrogen (BUN) was decreased in cows fed the CAS ration. Postpartum, we found serum protein to be decreased with the low DCAD diets while BUN was decreased in the CAS group. The low DCAD rations increased prepartum serum malondialdehyde concentrations, while postpartum total antioxidant capacity was lower in the HCLK and the AMS group. From these data, we conclude that AMS decreased prepartum intake due to compromised palatability. Intermediate protein metabolism was affected by the low DCAD diets, while parameters of oxidative stress were probably affected by acid–base balance and Ca homeostasis. 相似文献
10.
Sharifi H Nassiri SM Esmaelli H Khoshnegah J 《Journal of Feline Medicine and Surgery》2007,9(6):514-517
A 14-year-old female domestic shorthair cat was presented to Tehran University Veterinary Teaching Hospital for a persistent fever, anorexia, intermittent vomiting, weight loss and weakness. The main clinical signs were pale mucous membranes, dehydration and splenomegaly. The complete blood count and serum biochemistry tests revealed non-regenerative anaemia, thrombocytopenia and increased alkaline phosphatase (ALP) activity. An enzyme-linked immunosorbent assay (ELISA) test for feline leukaemia virus was negative. Blood film and bone marrow examination revealed a large number of immature eosinophils with variable sizes and numbers of faintly azurophilic granules. Cytochemical staining of blood film demonstrated 70% positive cells for ALP activity. Four percent CD34 positive cells were detected by flow cytometry. As eosinophilic leukaemia is difficult to identify by light microscopy, well-defined diagnostic criteria and the use of flow cytometry and cytochemical staining can improve the ability to correctly diagnose this type of leukaemia in cats. 相似文献