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排序方式: 共有313条查询结果,搜索用时 15 毫秒
1.
Jezie A. Acorda DVM MAgr Haruo Yamada DVM DVSc Seyed Mehdi Ghamsari DVM 《Veterinary radiology & ultrasound》1994,35(2):120-123
Ultrasonography of the liver of 49 Holstein-Friesian cows was performed, liver specimens were taken, examined microscopically and the fatty occupying rate (FOR) was calculated. Echoes from the hepatic B-mode ultrasonograms were quantified as histogram mean (Emean) and histogram mode (Emode) of echo amplitudes within various areas at a depth of 1–9 cm from the hepatic surface. Of the 49 animals, 26 had a normal liver and 23 had fatty infiltration of the liver, diagnosed through histopathological examination. Fatty occupying rate ranged from 1.7 to 64.5%, with 11 animals having 1–15% FOR (mild fatty infiltration), 6 having 15.1–30% FOR (moderate fatty infiltration) and 6 having > 30% FOR (severe fatty infiltration). At 1 cm, severe fatty infiltration had higher Emean and Emode than normal liver (p < 0.05). At 7 cm and 9 cm, moderate and severe fatty infiltration had lower Emeans and Emodes than normal liver (p < 0.001). The results suggest that digital analysis of hepatic ultrasonogram can be useful in the evaluation of the degree of fatty infiltration of the liver in dairy cattle. 相似文献
2.
Latifi Meysam Naderi Yousef Mortazavi Amin Bohlouli Mehdi Sadeghi Saadat 《Tropical animal health and production》2020,52(6):2917-2923
Tropical Animal Health and Production - The present study was conducted to estimate autosomal and sex-linked genetic parameters by restricted maximum likelihood method using four different... 相似文献
3.
Bijan Soleymani Kamran Mansouri Mohsen Rastegari-Pouyani Shahram Parvaneh Fatemeh Khademi Mehdi Sharifi Tabar Ali Mostafaie 《Reproduction in domestic animals》2021,56(2):270-277
Separation of X and Y chromosome-bearing sperm is an appropriate method for the selection of desired sex of offspring to increase the profit in livestock industries. The purpose of this study was the production of a monoclonal antibody against recombinant bovine sex-determining region Y protein for separation Y sperm. The hybridoma cells from splenocytes of immunized female's balb/C mice and Sp2/0 cells were made. The binding affinity of our monoclonal antibody (mAbSRY2) was compared with mouse monoclonal SRY-15. The Western blot method indicated that mAbSRY2 successfully detected the rbSRY protein. The specificity and sensitivity of mAbSRY2 is comparable to SRY-15 commercially ones. The SRY gene in 100% of bull semen contains the Y chromosome that had the strongest binding affinity to mAbSRY2 was synthesized. In other words, the binding affinity of semen contains the X sperms near the negative control. In general, this immunological method can help to separate X from Y sperms. However, the mAbSRY2 is bind to Y-bearing sexed sperm, but in the future; the sexed sperms need to apply in farms. 相似文献
4.
Masoud Selk Ghaffari DVM PhD Mehdi Marjani DVM PhD Majid Masoudifard DVM PhD 《Journal of Veterinary Cardiology》2009,11(1):67-69
A 3-year-old crossbreed male dog was presented with a history of blunt facial trauma. Skull radiographs showed right zygomatic arch fracture. An electrocardiogram revealed bradycardia, first-degree atrioventricular block and QT prolongation. Standard biochemical profile including electrolytes was normal. Atropine response test (0.04 mg/kg intravenously) restored normal sinus rhythm at a rate of 140 bpm with normal QT and PR intervals. This observation is consistent with oculocardiac reflex secondary to zygomatic arch fracture. 相似文献
5.
Jezie A. Acorda DVM Magr Haruo Yamada DVM DVSc Seyed Mehdi Ghamsari DVM 《Veterinary radiology & ultrasound》1994,35(3):196-200
Ultrasonography of the liver was performed in 200 Holstein-Friesian dairy cattle using a 3.5 MHz transducer with a linear array electronic scanner. Liver samples were taken, processed and examined microscopically and the fat occupying rate was calculated. The hepatic ultrasonograms were evaluated according to the presence of bright pattern, dark pattern, deep attenuation, vascular blurring and blurring of edges. Of the 200 animals, 96 had a normal liver, 63 had hydropic degeneration of the liver, 37 had fatty infiltration of the liver, 3 had liver dystrophy and I had hepatic amyloidosis, diagnosed through histopathological examination. Amyloidosis was characterized by bright pattern and blurring of edges. Liver dystrophy had higher percentages of bright pattern and blurring of edges than normal liver. Hydropic degeneration had higher percentages of dark pattern and blurring of edges than normal liver. Fatty infiltration had higher percentages of bright pattern, deep attenuation, vascular blurring and blurring of edges than normal liver. The present results suggest that different ultrasonographic patterns can be observed in various diffuse hepatocellular disorders in dairy cattle 相似文献
6.
7.
Mohammad Mehdi Oloumi Dariush Vosough Amin Derakhshanfar Mohammad Hadi Nematollahi 《Journal of Equine Veterinary Science》2011,31(8):470-474
This study was carried out to evaluate the healing potential of water-soluble extract of Plantago lanceolata as a topical ointment on experimental tendinitis in burros. Tendinitis was induced by injection of 2,500 U of bacterial collagenase in the superficial digital flexor tendon of both forelimbs of six male burros. Tendinitis was confirmed ultrasonographically. 48 hours after collagenase injection, two grams of 10% P lanceolata ointment was applied on one limb (treatment group) and the same amount of eucerin (the vehicle of the ointment) on the other limb (control group), every other day for 6 weeks. Ultrasonographic examination of the tendon was performed weekly during the study and mean cross-sectional area of the superficial digital flexor tendon was measured, which was found to increase significantly after injection of collagenase in both groups. From the third week, it decreased significantly in the treatment group in comparison with the control group. At the end of the study, the animals were euthanized for histopathological study of the tendons. In control group, degenerative changes in tendon could be seen, whereas significant degree of healing was observed in the treatment group. It can thus be concluded that the P lanceolata ointment was effective in promoting the healing process of the tendon. 相似文献
8.
Mehdi Zarifi Sébastien Buczinski Ali Rezakhani Mohammad Reza Mokhber Dezfouli Ali Khonsha 《Journal of Veterinary Cardiology》2012,14(3):415-421
ObjectivesTo study the effect of pregnancy and lactation on echocardiographic parameters in Holstein dairy cows.AnimalsNine multiparous high milk producing (HMP) dairy cows (producing more than 40 kg of milk per day in peak production) and 9 low milk producing (LMP) cows (producing less than 30 kg or milk per day in peak production).MethodsEchocardiography was performed twice; one month before calving and two months after calving.ResultsThe heart rate of HMP cows in the early lactation period was significantly higher than in the dry period. In LMP cows, there was a significant increase in left ventricular dimension in the early lactation period as compared to the dry period, and the interventricular septum in systole (IVSs) in the dry period was significantly thicker than early lactation period. In HMP cows, there was an increase in the right ventricular diameter in systole in the early lactation period as compared to the dry period. Left ventricular and aortic dimensions in the dry period of HMP were significantly higher than those of LMP cows. When the data were corrected for body weight, comparison of values of the dry period of HMP and LMP cows showed that left ventricular volume in systole in HMP was significantly higher and that IVSs, left ventricular fractional shortening and ejection fraction were significantly lower than in LMP cows.ConclusionsThis study demonstrated that lactation influences the intracardiac dimensions. The amount of milk production can influence echocardiographic parameters in dairy cows. 相似文献
9.
Jezie A. Acorda DVM Magr Haruo Yamada DVM DVSc Seyed Mehdi Ghamsari DVM 《Veterinary radiology & ultrasound》1995,36(4):322-326
Ultrasonography of the liver of 181 Holstein-Friesian cows was performed and blood samples were collected for analysis. The hepatic ultrasonograms were evaluated and the echoes were analyzed digitally. After slaughter, liver specimens were taken and examined histopathologically. Of the 181 animals, 120 had a normal liver and 61 had hydropic degeneration of the liver, diagnosed through histopathologic examination. Diagnostic accuracy rates for hydropic degeneration were determined based on the following test positive conditions: a) for biochemical analysis—high levels of aspartate aminotransferase, alanine aminotransferase, total bilirubin and non-esterified fatty acids; b) for ultrasonography—presence of dark pattern and blurring of edges; and c) for digital analysis—low echo means at 1 cm and 3 cm from the hepatic surface. Digital analysis had the highest overall specificity, accuracy and positive predictive values for hydropic degeneration, followed by ultrasonography. The results suggest that ultrasonography and digital analysis of hepatic ultrasonograms can be used for diagnosis of hydropic degeneration of the liver in place of biochemical analysis. 相似文献
10.
Lameness scoring system for dairy cows using force plates and artificial intelligence 总被引:2,自引:0,他引:2
Ghotoorlar SM Ghamsari SM Nowrouzian I Ghotoorlar SM Ghidary SS 《The Veterinary record》2012,170(5):126
Lameness scoring is a routine procedure in dairy industry to screen the herds for new cases of lameness. Subjective lameness scoring, which is the most popular lameness detection and screening method in dairy herds, has several limitations. They include low intra-observer and inter-observer agreement and the discrete nature of the scores which limits its usage in monitoring the lameness. The aim of this study is to develop an automated lameness scoring system comparable with conventional subjective lameness scoring by means of artificial neural networks. The system is composed of four balanced force plates installed in a hoof-trimming box. A group of 105 dairy cows was used for the study. Twenty-three features extracted from ground reaction force (GRF) data were used in a computer training process which was performed on 60 per cent of the data. The remaining 40 per cent of the data were used to test the trained system. Repeatability of the lameness scoring system was determined by GRF samples from 25 cows, captured at two different times from the same animals. The mean sd was 0.31 and the mean coefficient of variation was 14.55 per cent, which represents a high repeatability in comparison with subjective vision-based scoring methods. Although the highest sensitivity and specificity values were seen in locomotion score groups 1 and 4, the automatic lameness system was both sensitive and specific in all groups. The sensitivity and specificity were higher than 72 per cent in locomotion score groups 1 to 4, and it was 100 per cent specific and 50 per cent sensitive for group 5. 相似文献