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Identification and quantification of tylosin in animal feed by liquid chromatography combined with electrospray ionisation mass spectrometry 全文
2020
Przeniosło-Siwczyńska, Monika | Grelik, Aleksandra | Kwiatek, Krzysztof
The authorisation of tylosin as feed additive was withdrawn for reasons of human health concerning resistance of pathogenic bacteria. An analytical method for the identification and quantification of tylosin in animal feed was developed and validated. The samples were extracted using an acidified methanol:water mixture and solid-phase extraction was employed for the isolation of the antibiotic from diluted feed samples. Tylosin was analysed by liquid chromatography with electrospray ionisation mass spectrometric detection. The method’s performance was evaluated in adherence to the Commission Decision 2002/657/EC. The recovery of the analyte from spiked samples was determined to be in the range from 78.9% to 108.3% depending on tylosin concentrations. The CCα and CCβ values for tylosin in feeds were determined at 0.085 mg kg⁻¹ and 0.091 mg kg⁻¹, respectively. The method detection limit was found to be 0.035 mg kg⁻¹ and the quantification limit 0.05 mg kg⁻¹. The applicability of the developed method was tested by analysing real feed samples. A reliable LC-MS method was developed to identify and quantify tylosin in animal feed with a good repeatability and a high specificity and sensitivity. Because of these characteristics, the proposed method is applicable and could be deemed necessary within the field of feed control and safety.
显示更多 [+] 显示较少 [-]Investigation and sequence analysis of avian polyomavirus and psittacine beak and feather disease virus from companion birds in eastern Turkey 全文
2020
Adiguzel, Mehmet Cemal | Timurkan, Mehmet Ozkan | Cengiz, Seyda
Avian polyomavirus (APV) and psittacine beak and feather disease virus (PBFDV) induce contagious and persistent diseases that affect the beaks, feathers, and immune systems of companion birds. APV causes hepatitis, ascites, hydropericardium, depression, feather disorders, abdominal distension, and potentially death. PBFDV can induce progressive beak deformity, feather dystrophy, and plumage loss. We conducted the first prevalence survey of both APV and PBFDV infections in companion birds in eastern Turkey. A total of 113 fresh dropping samples from apparently healthy companion birds were collected in a random selection. The dropping samples were analysed for PBFDV and APV by PCR. Positive samples were sequenced with the Sanger method. The sequence was confirmed through alignment and the phylogenetic tree generated through the maximum likelihood method computationally. PBFDV and APV were detected in a respective 48.7% and 23.0% of samples. Coinfection was found in 12.4% of the samples, these all being from budgerigars (Melopsittacus undulatus). APV and PBFDV were detected in budgerigar and cockatiel (Nymphicus hollandicus) samples. This report provides a foundation for future studies on the influence of these viruses on the health of companion birds. These high positive rates for both pathogens emphasise that healthy M. undulatus and N. hollandicus in eastern Turkey may be prone to the emergence and spread of APV and PBFDV with subclinical potential.
显示更多 [+] 显示较少 [-]Comparison of a barium chloride test with ELISA for pregnancy detection in cows 全文
2020
Dana, Omer Ismaeel | Ghaidan, Mnnat Talib | Mukhtar, Rafiq Hamakarim | Dyary, Hiewa Othman
Early detection of pregnancy is vital for appropriate reproductive management programmes to facilitate the rapid re-insemination of non-pregnant females and reduce the calving interval. A barium chloride test was compared with a commercial progesterone ELISA to detect pregnancy in non-descriptive cows and investigate if it could be applied as an alternative to ELISA in the field. Blood and urine samples were collected from 74 cows with recorded insemination dates. The progesterone ELISA and barium chloride assay were implemented to detect progesterone (P4) in blood and urine specimens, respectively. The cows' reproductive systems were examined after they were slaughtered to determine the uterus's status. Macroscopic examination of the uterus was used as a reference standard for both tests. The sensitivity rates of the P4 ELISA and barium chloride test to detect pregnant cows were 100.0% and 79.4%, and to detect the corpus luteum (CL) were 83.0% and 87.0%, respectively, their sensitivity increasing in the presence of the CL. The ELISA and barium chloride tests were 79.7% and 52.7% accurate in the diagnosis of pregnancy. The accuracy of the barium chloride test in CL detection increased to 81.0%, and that of the ELISA to 86.4%. There were no significant differences (P = 0.052) between the barium chloride assay and ELISA when they were utilised for the identification of the CL. The barium chloride test can be an inexpensive and time-saving alternative to ELISA in pregnancy diagnosis when the insemination date is known.
显示更多 [+] 显示较少 [-]Molecular study of Cysticercus tenuicollis from slaughtered sheep in Sulaymaniyah province, Iraq 全文
2020
Mohammed, Aram Ahmad
Cysticercosis caused by the larval stage of Taenia hydatigena is economically the most important endemic parasitic disease in Iraq. Few data are available relating to the genetic divergence of this helminth. This study aimed to molecularly characterise Cysticercus tenuicollis isolates from sheep in Sulaymaniyah province, Iraq. DNA extraction and amplification of specimens of C. tenuicollis from 46 sheep were conducted by PCR for the mitochondrial 12S rRNA gene. The 19 amplicons were subjected to purification and partial sequencing. Five 12S rRNA nucleotide sequence haplotypes were found. The pairwise nucleotide difference between haplotypes of 12S rRNA gene ranged from 0.2% to 0.7%. Four out of the five haplotypes of C. tenuicollis contained one to two base mutations and were discovered in Iraq for the first time, and this may be a unique mutation globally which has not been recorded previously. Three newly recorded haplotypes contained only one single mutation, and the other one contained two mutations. Phylogenetic analysis showed that all isolated strains were closely related to Iranian sheep isolates. Four new strains of T. hydatigena were discovered for the first time in the study area.
显示更多 [+] 显示较少 [-]The main DNA viruses significantly affecting pig livestock 全文
2020
Swine DNA viruses have developed unique mechanisms for evasion of the host immune system, infection and DNA replication, and finally, construction and release of new viral particles. This article reviews four classes of DNA viruses affecting swine: porcine circoviruses, African swine fever virus, porcine parvoviruses, and pseudorabies virus. Porcine circoviruses belonging to the Circoviridae family are small single-stranded DNA viruses causing different diseases in swine including poly-weaning multisystemic wasting syndrome, porcine dermatitis and nephropathy syndrome, and porcine respiratory disease complex. African swine fever virus, the only member of the Asfivirus genus in the Asfarviridae family, is a large double-stranded DNA virus and for its propensity to cause high mortality, it is currently considered the most dangerous virus in the pig industry. Porcine parvoviruses are small single-stranded DNA viruses belonging to the Parvoviridae family that cause reproductive failure in pregnant gilts. Pseudorabies virus, or suid herpesvirus 1, is a large double-stranded DNA virus belonging to the Herpesviridae family and Alphaherpesvirinae subfamily. Recent findings including general as well as genetic classification, virus structure, clinical syndromes and the host immune system responses and vaccine protection are described for all four swine DNA virus classes.
显示更多 [+] 显示较少 [-]Cytotoxic and apoptotic effect of nanoclinoptilolite on canine osteosarcoma cell lines 全文
2020
Ulutaş, Pınar Alkım | Kıral, Funda | Ulutaş, Bülent | Aşıcı, Gamze Sevri Ekren
Clinoptilolite has antiviral, antibacterial, anti-inflammatory, antidiabetic, and anticancer properties due to its biological activities. In various cancer cell culture studies, it has been reported effective against tumour cells and gave positive results in treatment of various tumours in dogs. No study was found on the effects of the nanoparticulate form, nanoclinoptilolite, on cancer cells. The aim of this study was to determine its cytotoxic and apoptotic effects in canine osteosarcoma (OSA) cell culture. Doses at 50% inhibitory concentration were determined by measuring the dose- and duration-dependent cytotoxicity of nanoclinoptilolite on canine D-17 osteosarcoma cells by methylthiazol tetrazolium (MTT) test for 24 h, 48 h, and 72 h. Murine caspase-3 and -7 activity and expression levels of the BAX and BCL2 genes were measured using RT-PCR to investigate the apoptotic effect. Nanoclinoptilolite decreased cell viability and induced caspase-3- and -7-mediated apoptosis in treated canine OSA cells. Furthermore, its application to canine OSA cells downregulated the expression of BCL2 and upregulated the expression of proapoptotic BAX. Clinoptilolite, which was previously demonstrated to have anticancer properties, decreased cell viability effectively and rapidly and increased the apoptotic cell ratio in a novel use in nanoparticle form, exhibiting this effect by increasing the BAX/BCL2 ratio.
显示更多 [+] 显示较少 [-]Efficacy of natural formulations in bovine mastitis pathology: alternative solution to antibiotic treatment 全文
2020
Pașca, Claudia | Mărghitaș, Liviu Alexandru | Dezmirean, Daniel Severus | Matei, Ioana Adriana | Bonta, Victorița | Pașca, Ioan | Chirilă, Flore | Cîmpean, Adrian | Iosif Fiț, Nicodim
Bovine mastitis is an inflammatory disease of the udder that causes important economic losses in the animal breeding and dairy product industries. Nowadays, the conventional livestock antibiotic treatments are slowly being replaced by alternative treatments. In this context, the main aim of this study was to evaluate the efficacy of natural products in alternative treatment of bovine mastitis. Two natural formulations with previously suggested in vitro antimicrobial effect were tested in vivo on mastitic cows. Animals with a positive diagnosis for mastitis (n = 20) were divided into three treatment groups: two groups (n = 8) were administered formulations of propolis, alcoholic extracts of Brewers Gold and Perle hops, plum lichen, common mallow, marigold, absinthe wormwood, black poplar buds, lemon balm, and essential oils of oregano, lavender, and rosemary designated R4 and R7 (differing only in the latter being more concentrated) and one group (n = 4) a conventional antibiotic mixture. In vivo efficacy of treatments was evaluated by somatic cell and standard plate counts, the treatment being considered efficacious when both parameters were under the maximum limit. R7 was effective in the most cases, being therapeutically bactericidal in six out of eight cows, while R4 gave good results in three out of eight cows, and conventional antibiotics cured one out of four. These results suggest the possible therapeutic potential of these natural products in bovine mastitis.
显示更多 [+] 显示较少 [-]E-test determination of antifungal susceptibility of Candida species isolated from turkeys 全文
2020
Sokół, Ireneusz | Tokarzewski, Stanisław | Bobrek, Kamila | Gaweł, Andrzej
Candida species are a natural component of the intestinal tract microflora, but in favourable conditions they can cause superficial, mucosal, or even systemic candidiasis. Poultry production might be a source of human drug-resistant yeast infections, including Candida spp. The limited data concerning the antifungal susceptibility of poultry Candida isolates prompted us to carry out research to determine the susceptibility of isolates from turkey intestinal tracts. The beak cavity, crop and cloaca were swabbed of 580 turkeys from 58 flocks in western Poland. The susceptibility tests were conducted using the E-test method with amphotericin B, fluconazole, itraconazole, and voriconazole on 52 isolates of C. albicans, C. catenulata, C. glabrata, C. palmioleophila, C. rugosa, C. krusei and C. lusitaniae. All isolates were susceptible to voriconazole. According to the MIC values obtained for amphotericin B and fluconazole, all Candida spp. isolates were classified as susceptible according to the described breakpoints except for C. krusei, which was the only isolate that was amphotericin B-, fluconazole- and itraconazole-resistant. The susceptibility to itraconazole varied: 11 of the Candida isolates were susceptible (21.1%), 29 were dose-dependently susceptible (55.8%), and 12 isolates were resistant (23.1%). There are few resistant strains of Candida in turkeys, and the drug resistance varies. When Candida passes from turkeys to humans, there is a wide range of antifungal treatment options.
显示更多 [+] 显示较少 [-]Effects of α-enolase gene silencing on reproductive-related hormone receptor expression and steroid hormone synthesis of primary granulosa cells from goose F1 follicles 全文
2020
Ji, Hong | Niu, Chun-Yang | Zhang, Hong-Liang | Guo, Jing-Ru | Zhen, Li | Lian, Shuai | Yang, Chuang | Yang, Huan-Min | Wang, Jian-Fa
Enolases are enzymes in the glycolytic pathway, which catalyse the reversible conversion of D-2-phosphoglycerate into phosphoenol pyruvate in the second half of the pathway. In this research, the effects of α-enolase (ENO1) on steroid reproductive-related hormone receptor expression and on hormone synthesis of primary granulosa cells from goose F1 follicles were studied. Primary granulosa cells from the F1 follicles of eight healthy 8-month-old Zi geese were separated and cultured. An ENO1 interference expression vector was designed, constructed and transfected into primary cultured granulosa cells. The mRNA expression levels of follicle-stimulating hormone receptor (FSHR), luteinising hormone receptor (LHR), oestrogen receptor α (ER α), oestrogen receptor β (ER β), growth hormone receptor (GHR) and insulin-like growth factor binding protein-1 (IGFBP-1) in the cells were evaluated as were the secretion levels of oestradiol, activin, progesterone, testosterone, inhibin and follistatin in cell supernatant. α-enolase gene silencing reduced the expression of FSHR, LHR, ERα, ERβ, GHR, and IGFBP-1 mRNA, potentiated the secretion of oestrogen, progesterone, testosterone, and follistatin of granulosa cells, and hampered the production of activin and inhibin. ENO1 can regulate the reactivity of granulosa cells to reproductive hormones and regulate cell growth and development by adjusting their hormone secretion and reproductive hormone receptor expression. The study provided a better understanding of the functional action of ENO1 in the processes of goose ovary development and egg laying.
显示更多 [+] 显示较少 [-]The influence of high and low doses of acrylamide on porcine erythropoiesis 全文
2020
Snarska Anna | Palus Katarzyna | Wysocka Dominika | Rytel Liliana
Due to the widespread occurrence of acrylamide in the environment, its likely carcinogen status, and the suitability of the pig model as a human analogue, the authors decided to evaluate the impact of high and low doses of this compound on the processes of erythropoiesis in swine bone marrow.
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