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Renal toxicity of titanium dioxide nanoparticlesin male albino rats
2018
Abdou, Kh. A | walaa A. Moselhy | Hanaa M.Mohammed | El-Shaymaa El-Nahass | Ahlam G. Khalifa
Nanoparticles have many characteristics that make them suitable for biological and medical applications. Uptake of thesenano particulates into animals and humans bodiesthrough different routes may exhibit potential side effects. Titanium dioxide (TiO2) is a common additivethat is increasingly used in consumer products, food,pharmaceutical dosage forms and cosmetic articles. In this study, the effects of oral administration of TiO2 nanoparticles (500 mg| kg .bw) for 60 days were investigated on kidney function and histopathological changes. The body weight gain and kidney/body weight ratio showed no significant changes in comparison with control group. There was a significant decrease in total thiol levels in kidney homogenate, the biochemical changes was supported by histopathologicalultration. In conclusion the data shows that the oral administration of TiO2 NPs may lead to renal toxicity in experimental rats.
显示更多 [+] 显示较少 [-]Isolation, molecular characterization and pathogenicity studies of infectious bursal disease field virus isolates
2018
M. M. Amer | K. M. El-Bayomi | M. Abd-A. Kotkat | Wafaa A. Abdel-Ghany | M. A. Shakal | Sherein S. Abdel-Gaied
This study was carried out to investigate the prevalence, molecular characterization and pathogenicity of field infectious bursal disease virus (IBDV) isolates. Nine isolates of IBDV were isolated from 13 naturally infected broiler flocks. Detection of IBDV antigen was carried out by agar gel precipitation test (AGPT), followed by virus isolation in specific pathogen free (SPF) embryonated chicken eggs (ECE) and finally molecularly characterized and identified using reverse transcriptase polymerase chain reaction (RT-PCR). The obtained nine strains of IBDV by RT-PCR were further classified by using restriction fragment length polymorphism (RFLP) technique into (4) classical, (3) variant and (2) very virulent (vv) IBDV serotype (I). The pathogenicity of the isolated IBDV strains was detected by three passages in SPF ECEs and by experimental infection of one hundred 14 days old maternally immune layer chicks. The results showed that the mortality rate of the embryos was increased by increase the number of passages till the third passage where it reached 100% for all IBDV strains and the embryos showed typical lesions of IBDV. Chicks inoculated with variant IBDV strains showed morbidity rates of 60-80 %, without mortalities. Sacrificed birds showed atrophied bursae and thymus glands and enlarged thickened proventriculus. Groups infected with classical IBDV strains showed morbidity rates 40- 60,% with mortality 0-20%. The detectable lesions were muscular hemorrhages with variable bursal lesions. Inoculated chicks with vvIBDV strains showed 50-70% morbidity and mortality of rate was 30% with lesions of muscular hemorrhages, severe nephrosis with ureates in the ureters, hemorrhagic bursitis and pin point hemorrhages on the proventricular glands. Control negative non-infected group showed neither clinical signs nor mortalities along the observation period. The histopathological effect (lesion score) of IBDV strains on the bursa, spleen and thymus glands confirmed the previously mentioned results and revealed that the highest severity (score) for these organs were induced by vv IBDV strains.
显示更多 [+] 显示较少 [-]Involvement of Oxidative Stress in Cardiovascular Diseases
2018
Mahmoud Rushdi Abd Ellah
Many research studies support the evidence that free radicals stress is involved in the pathogenesis of many diseases in human and animals. The current review aimed to throw the light on sources of free radicals in the cardiovascular system, involvement of oxidative stress in cardiovascular diseases and the role of the antioxidants in alleviating the damage produced by oxidative stress.
显示更多 [+] 显示较少 [-]Assessment of stress in relation to sheep shearing by using behavioural and physiological measurements
2018
H.H. Emeash | A.S. Mostafa | N. M. Abdel-Azem
This study was carried out in Sids Agricultural Research Station belonging to Animal Production Research Institute in Beni-Suef governorate on a total number of forty apparently healthy ewe lambs with average weight of 28±0.5 kg to clarify the effect of shearing as a stressor on comfort, feeding and social behaviour and blood cortisol level. Ewe lambs were divided into three groups, the first one (n=10) is shorn at spring, the second (n=10) is shorn in autumn and the third (n=20) is kept as a control. Results showed that there was no significant difference in patterns of comfort behaviour between shorn and unshorn ewes except for grooming behaviour which was significantly (p<0.01) increased in shorn than unshorn groups. Blood cortisol level was significantly (p<0.05) higher in ewes shorn in spring and autumn at time of shearing (zero minute) than pre-treatment (-20 minutes) and post-treatment time (3 hours following shearing). So the cortisol measurements is a useful indicator of short-term stresses from handling or husbandry procedures such as shearing.
显示更多 [+] 显示较少 [-]ffect of castration and docking of lambs on maintenance behaviour and cortisol level
2018
H.H. Emeash | A.S. Mostafa | N. M. Abdel-Azem
Thirty apparently healthy lambs with average weight and age of 5.8±0.5 kg and 15±1.6 days respectively were chosen in Sids Agricultural Research Station belonging to Animal Production Research Institute in Beni-Suef governorate to investigate the effect of castration and docking on maintenance behaviour and blood cortisol level during and after such operations. Lambs were classified into castration (n=10), docking (n=10) and control (n=10) groups. The results revealed that castration and docking could significantly affect the behaviours of standing idle, recumbency, sleep, suckling and ingestion in lambs. Moreover, blood cortisol level was significantly (p<0.05) increased after operation in castrated and docked lambs as compared to the time before, at operation and 3 hours after operation.
显示更多 [+] 显示较少 [-]Alterations in the clinical, hematological and biochemical pictures in abomasal displacement in cows in Egypt
2018
H. M. El-Attar | Yassein M. Abd El-Raof | M. M. Ghanem
This study was carried out on twelve Holstein dairy cows. Five cows were clinically healthy and considered as control; three cows with left displacement of abomasum (LDA) and four cows with right displacement of abomasum (LDA). Diagnosis of DA based on clinical examinations and confirmed by ultrasonography. The Hb, PCV%, total leucocytic count, neutrophils and abomasal fluid pH were significantly increased (P<0.05) in RDA compared to control. Serum biochemical analysis showed significant reductions of sodium, potassium, chloride and calcium in LDA and RDA and significant increases (P < 0.05) in glucose and total proteins in RDA compared to the control. Moreover, there were significant increases (P<0.001) in ALT, AST, LDH, CPK, urea and creatinine in LDA and RDA compared to control. In conclusion, abomasal displacement produces alterations in the clinical, hematological and biochemical picture compared to control healthy cow and these alterations may vary according to the type of displacement
显示更多 [+] 显示较少 [-]Effect of different sources of non-fiber carbohydrate on ruminal pH and in vitro digestibility of tropical forage
2018
Viviane Borba Ferrari | Angélica Patrícia Ordoñez Diaz | Nara Regina Brandão Cônsolo | Rafael Teixeira de Sousa | Frederich Diaz Rodriguez | Luis Felipe Prada e Silva
The present study aimed to evaluate non-fiber carbohydrates (NFC) in sugarcane-based diets on rumen pH, and forage digestibility, and to describe NFC degradation curves. The study consisted of two trials. For the first trial, three rumen cannulated steers, BW of 350 ± 15 kg (mean ± SE), were assigned in a 3×3 Latin Square (LS) design. They were fed diets containing finely-ground (0.9 mm average particle size) corn (GC), steam-rolled corn (SRC), or pelleted citrus pulp (PCP). Each period had 14 d, with the first 12 for adaptation. The 13th d was for serial measurement of rumen pH, and the14th for rumen fluid collection and in vitro incubation for DM and NDF digestibility (IVDMD and IVNDFD) of bermudagrass hay (Hay), corn (CS), and sugarcane (SS) silages. In the second trial, rumen fluid of a cannulated bull, fed corn silage and a regular concentrate, was collected for in vitro digestion of NFC for multiple time points. The incubation results were used to adjust the NFC degradation curves, and calculate lag-time, feed fractions, and degradation rate. Data from first trial was analyzed in a 3×3 LS. The model for the digestibility parameters included fixed effects of forage (Feed), diets with NFC (Diet), and their interaction (Feed × Diet), and random effect of animal and period. The model for rumen pH included fixed effect of diet, time as repeated measures, animal and period as random effects. The significance was considered at probability ≤ 5% (α = 0.05). The NFC degradation curves were adjusted using the PROC NLIN procedure from SAS, and equation parameters compared using confidence intervals. There was a Diet × Time interaction on rumen pH (P = 0.04), where SRC decreased pH compared to PCP and GC diets at the time 6 h, only. There was no Feed × Diet interaction effect (P > 0.05) for any digestibility parameter. There was a Feed effect on both IVDMD and IVNDFD, either after 30 or 48 h incubation (P < 0.01). The CS had the greatest IVDMD, followed by SS and Hay, after 30 and 48 h of incubation. The CS had the greatest IVNDFD after 30 h, compared to SS and Hay. However, for IVNDFD after 48 h, CS presented the greatest mean, followed by SS and Hay. The rumen fluid from animals fed SRC decreased both IVDMD and IVNDFD (P < 0.05) of all roughages after 48 h. Results from the second trial showed that the PCP had lower Lag Time, B fraction and greater kd compared to both corn sources, and SRC had greater kd than GC. In conclusion, the SRC diet decreased rumen pH 6 h after feeding and, consequently, decreased fiber digestibility of the tropical forage sources evaluated. Although the PCP had lower lag time, and faster rate of degradation of B fraction, it did not negatively affect rumen pH or fiber digestibility of forage.
显示更多 [+] 显示较少 [-]Productive profile of cattle-rearing farms in the state of Minas Gerais, Brazil, 2002
2018
Cristiane de Morais Alves | Elaine Maria Seles Dorneles | Luciana Faria de Oliveira | José Soares Ferreira Neto | Vitor Salvador Picão Gonçalves | José Ricardo Lôbo | Marcos Bryan Heinemann | Andrey Pereira Lage
A descriptive cross-sectional study was conducted in the state of Minas Gerais, Brazil, with the aim to assess aspects of cattle production. A multistage clustering model was used to select 2,202 farms in seven cattle production strata in the state, and a questionnaire was applied to obtain information related to the characterization of the farms and their management of animal reproduction and production. The study showed that livestock-rearing in Minas Gerais continues to be unspecialized. Triângulo Mineiro and North were the regions that used most technology and had highest beef cattle activity. The Zona da Mata region showed the least use of technology and had the smallest farms. Milk production in this state was distributed among all strata, but was concentrated among a few producers in the stratum of highest production, especially in the region of Alto Paranaíba. This study showed a great heterogeneity among the strata regarding the characteristics of type of exploitation, type of rearing, herd size, specialization and milk production. Thus, it validated the stratification established by the Ministério da Agricultura Pecuária e Abastecimento – MAPA (Brazilian Ministry of Agriculture, Livestock and Food Supply), thereby suggesting that these strata should be maintained for further epidemiological studies.
显示更多 [+] 显示较少 [-]Isoelectric focusing of proteins in the pH gradient as a tool for identification of species origin of raw meat
2018
Różycki, Mirosław | Chmurzyńska, Ewa | Bilska-Zając, Ewa | Karamon, Jacek | Cencek, Tomasz
Health, religious, and commercial aspects justify the need for meat species identification. The lack of officially approved methods prompts the undertaking of research on validation of isoelectric focusing of proteins (IEF) for official purposes. Samples were prepared from pigs (Sus scrofa ferus domestica), cattle (Bos taurus), and poultry (Gallus gallus domesticus). Meat mixtures were made by blending 50%, 25%, 10%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.2% meat of other species. Samples were examined on ultrathin polyacrylamide gels with pH 3–9 gradient. The results of the study confirmed the stable and reproducible pattern of meat protein bands. The detection limit of raw meat admixtures from pigs, cattle, and poultry mostly ranged from 2% down to 0.2% (0.2% for poultry). However, the IEF method can be used to detect the addition of pig meat to bovine meat in an amount higher than 3%. At the significant mixture level (i.e at least 5% addition of meat of another species) IEF proves itself with 100% specificity, sensitivity, and accuracy. The achieved detection limits provide a basis for recommending the IEF method for routine tests in laboratories detecting the species origin of meat.
显示更多 [+] 显示较少 [-]Use of a new LC-MS method for the determination of pyrrolizidine alkaloids in feeds
2018
Kowalczyk, Ewelina | Kwiatek, Krzysztof
Pyrrolizidine alkaloids (PAs) are secondary metabolites produced by many plant species. Due to their toxicity PAs can pose a risk to human and animal health. To detect the toxic compounds in feed materials a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed. PAs were extracted with sulphuric acid and purified with cation exchange cartridges. A newly developed solvent mixture consisting of ethyl acetate, methanol, acetonitrile, ammonia, and triethylamine was used to wash alkaloids from the cartridges. After evaporation the residues were reconstituted in water and methanol mixture and subjected to LC-MS analysis. The developed method was validated according to SANTE/11945/2015 guidelines. The recovery was from 84.1% to 112.9%, the repeatability ranged from 3.0% to 13.6%, and the reproducibility was from 4.8% to 18.9%. A sensitive and selective method for determination of PAs in feed materials has been developed and validated. All evaluated validation parameters were in accordance with EU Reference Laboratories document no. SANTE/11945/2015. Almost 41% of the analysed feed samples were positive for the presence of at least one PA.
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