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951.
952.
Hanif NQ Muhammad G Siddique M Khanum A Ahmed T Gadahai JA Kaukab G 《British poultry science》2008,49(5):632-642
1. Toxic effects of two concentrations (0.5 and 1 mg/kg) of ochratoxin A (OTA) and attenuating effects of a toxin deactivator (Mycofix Plus(MTV INSIDE)) containing the yeast Trichosporon mycotoxinivorans on the performance (feed conversion ratio; body weight gain), serum enzymes (lactate dehydrogenase, gamma-glutamyltranspeptidase and aspartate aminotransferase) and clinico-pathomorphology of internal organs were studied in 270 one-day-old broiler chicks divided into 9 groups over a 42-d period. 2. Feed conversion ratios (FCR) in groups fed toxin deactivator were improved compared with groups receiving OTA only. An increase in the relative weight of kidney and liver was observed in groups fed 0.5 and 1 mg/kg OTA on day 42 of the experiment as compared with the control group. In contrast, relative weights of bursa of Fabricius and spleen were not significantly affected in experimental groups exposed to OTA as compared to control groups determined on days 28 and 42 of age. 3. Serum enzymes (LDH, GGT and AST) values in OTA treated groups determined on days 28 and 42 were higher than those of the control group. 4. Histopathological examination of kidney on day 42 revealed degenerative changes in the epithelial cells of the proximal convoluted tubules and massive necrosis of the proximal tubular epithelial cells. These changes were less marked in birds receiving 0.5 mg/kg OTA than in those receiving 1 mg/kg. In general, histological changes in kidneys, liver, bursa and spleen were less pronounced in birds receiving OTA and toxin deactivator concomitantly. 5. Dietary OTA at 0.5 and 1 mg/kg adversely affects FCR, increases the serum liver enzymes and induces pronounced pathomorphological and histological changes in internal organs of broiler chicks. Co-administration of OTA with deactivator attenuated the harmful effects. 相似文献
953.
Expression profile of myostatin mRNA during the embryonic organogenesis of domestic chicken (Gallus gallus domesticus) 总被引:2,自引:0,他引:2
Sundaresan NR Saxena VK Singh R Jain P Singh KP Anish D Singh N Saxena M Ahmed KA 《Research in veterinary science》2008,85(1):86-91
Myostatin is a potent growth and differentiation factor involved in skeletal muscle tissue formation in vertebrates. However, recent studies in chicken embryo suggested that the myostatin was expressed even before the establishment of myogenic lineage. No studies have thus far been reported in birds to define the role of myostatin during the embryonic organogenesis. The present experiment was designed for studying the expression profiles of myostatin mRNA in the chicken liver, heart, brain, and intestine during their morphogenesis, using real-time PCR. The myostatin mRNA expression was significantly upregulated in liver during E15-E18. Similar results were observed during the development of chicken heart. In brain, the expression of myostatin was upregulated from E4 onwards. In intestine, the expression of myostatin was significantly increased many folds on E9-E18. Therefore, the increase in myostatin expression might be related to the growth of liver and heart on days E12-E18; morphogenesis and growth of brain during E15-E18; and morphogenesis and differentiation of intestine during E9-E18. In the present study, the tissue-specific expression of myostatin gene in chicken is similar to fishes, but different from that in mammals. Further, the inspection of chicken genome also suggested that there is no differentiation of GDF-8 and -11. A recent finding suggests that the chicken myostatin gene is closely related to mammals than fishes. Therefore, we propose that the chicken myostatin gene might have diverged in its function between teleosts and mammals. Indeed it is possible that its function might have only become fully differentiated to serve as a control of muscle mass in mammals. 相似文献
954.
Ahmed M Kimura K Soliman M Yamaji D Okamatsu-Ogura Y Ishioka K Makondo K Hagiwara K Saito M 《Veterinary journal (London, England : 1997)》2008,176(3):361-368
This study examined the mitogenic response of bovine peripheral T lymphocytes to leptin, a pleiotropic hormone regulating food intake and energy expenditure. Leptin alone slightly suppressed proliferation of T lymphocytes in the presence of concanavalin A (ConA). Leptin also inhibited proliferation of T lymphocytes induced by anti-CD3 antibody. ConA treatment activated some protein kinases, including p44/p42(MAPK) and Akt/PKB, while anti-CD3 antibody treatment increased mRNA expression of suppressor of cytokine signalling (SOCS) 3, interferon (IFN)gamma, interleukin (IL) 2 and IL4 in T lymphocytes. Leptin alone increased only SOCS3 mRNA expression. Simultaneous treatment with mitogens and leptin enhanced IFNgamma mRNA expression but decreased IL2 mRNA expression, without any synergistic effect on phosphorylation of protein kinases or mRNA expression of SOCS3 and IL4. These results suggest that leptin modulates bovine T lymphocyte functions. 相似文献
955.
The New Zealand White (NZW) was superior significantly ( P < 0.05) to the Californian (Cal) breed in final body weight, final total body solids and preslaughter weight. In contrast, Cal showed greater plasma creatinine ( P < 0.001) than the NZW. The differences in the other traits were not significant. NZW also showed higher dressing percentage and Cal showed higher mortality percentage. The Temperature-humidity Index (THI) values indicated absence of heat stress in the first period (mild period) and exposure to moderate (very close to severe) heat stress in the second one (hot period). The heat stress conditions caused significant ( P < 0.001, 0.01 or 0.05) decreases in each of final body weight, daily body gain, daily feed intake, final total body solids, solids daily gain, plasma total protein, albumin, globulin, total lipids, glucose, thyroid hormone T3, sodium, potassium, calcium, magnesium and phosphorus and preslaughter weight. At the same time, significant ( P < 0.001 or 0.01) increases occurred in each of water intake, water/feed ratio, total body water (mL/100 g body solids), blood urea-N, creatinine, respiration rate and rectal, skin and ear temperatures. The interaction of breed x period effects was significant ( P < 0.01 or 0.05) on plasma creatinine and hind-limb cut. Estimations of 'adaptability' to the subtropical environment of Egypt were found to be 83.1% for NZW and 82.6% for Cal breeds. 相似文献
956.
957.
At least two genetically distinct large Babesia species infective to sheep and goats in China 总被引:3,自引:0,他引:3
Liu AH Yin H Guan GQ Schnittger L Liu ZJ Ma ML Dang ZS Liu JL Ren QY Bai Q Ahmed JS Luo JX 《Veterinary parasitology》2007,147(3-4):246-251
A fatal disease of sheep and goats in the northern part of China has been reported to be due to Babesia ovis. However, some characteristics of the causative agent in recent reports are not in accordance with the original attributes ascribed to this parasite. Therefore, the 18S small subunit ribosomal RNA (18S rRNA) genes of a number of Babesia isolates in China were sequenced and compared with that of other Babesia and Theileria species in an attempt to clarify their taxonomic position. In the present study, seven Babesia isolates were collected from distinct areas of northern China, and the 18S rRNA genes were amplified and sequenced. The phylogenetic trees were inferred based on 18S rRNA gene sequences of the Chinese ovine Babesia isolates and some of ovine Babesia and Theileria species available in GenBank. In the phylogenetic tree, Babesia sp. isolates from Madang, Tianzhu, Lintan, Ningxian, Hebei and Liaoning all grouped with B. motasi with 88.2-99.9% identity, while Babesia sp. Xinjiang grouped in a separate clade between B. ovis and B. crassa with 79.7-81.2% identity. The results indicated that there are at least two distinct Babesia species groups-B. motasi and Babesia sp. Xinjiang, the latter was distinctly different from other ovine Babesia isolates from China with less than 86.6% identity. 相似文献
958.
Induction of proinflammatory cytokines and caspase-1 by leptin in monocyte/macrophages from holstein cows 总被引:3,自引:0,他引:3
Ahmed M Shaban Z Yamaji D Okamatsu-Ogura Y Soliman M Abd Eldaim M Ishioka K Makondo K Saito M Kimura K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(5):509-514
The proliferation of peripheral blood mononuclear cells (PBMC) containing both monocyte/macrophages and T lymphocytes increased after treatment with T-cell mitogen (concanavalin A: Con A). PBMC treated with either leptin alone or combination of leptin and ConA showed enhanced proliferative activity by 10-40%, compared with those treated with ConA alone. In contrast, isolated T lymphocytes treated with leptin and ConA showed lowered proliferative activity than the ConA-treated alone, indicating that leptin induced production of some cytokines from monocyte/macrophages, that subsequently resulted in enhancement of T lymphocytes proliferation in PBMC. Among the cytokines examined, monocyte/monocytes constitutively expressed interleukin (IL)-1beta, IL-12p35, IL-18 mRNA, and faintly expressed tumor necrosis factor (TNF)-alpha and IL-12p40 mRNA. Leptin treatment augmented the monocyte/macrophages mRNA expression of only TNF-alpha and IL-12p40 to comparable levels of cells treated with lipopolysaccharide (LPS). However, leptin treatment increased monocyte/macrophages production of IL-1beta as well as TNF-alpha, and induced the mRNA expression of caspase-1, which is shown to mediate the conversion of latent pro-IL-1beta and pro-IL-18 to active forms. These results suggest that leptin directly acts on monocyte/macrophages to produce factors that induce T lymphocytes proliferation such as IL-12p35/p40 complex through IL-12p40 induction and IL-1beta/IL-18 production through caspase-1 induction. 相似文献
959.
Maiy M. M. Abdallah Ibrahim A. Adam Tamadur M. Abdalla Sanaa A. Abdelaziz Mohamed E. Ahmed Imadeldin E. Aradaib 《Irish veterinary journal》2015,69(1):6
Background
Rift valley fever (RVF) is a mosquito-borne viral disease of domestic livestock and wild ruminants. In camels RVF may cause abortion among pregnant camels, but is most often asymptomatic among other camels. In this study, a seroepidemiological survey was conducted to determine the prevalence of RVFV antibodies and to identify the potential risk factors associated with RVFV seropositivity among the Sudanese one-humped camel (Camelus dromedaries) in Khartoum State, Sudan. A cross sectional study was conducted in Khartoum State, Sudan, in a total of 240 camels selected randomly from four localities. Sera sampled were tested for the presence of RVFV-specific immunoglobulin G (IgG) antibodies using a competitive enzyme-linked immunosorbent assay (c-ELISA).Results
RVFV seropositivity was recorded in 23 out of 240 animals, prevalence rate of 9.6 % among camels in Khartoum State. Age (OR?=?8.29, p-value?=?0.04) and heavy rainfall (OR?=?5.36, p value?=?0.01) were recorded as potential risk factors for contracting RVF.Conclusions
Older age and heavy rainfall were considered as potential risk factors for seropositivity to RVF. Surveillance for RVF among camels and distribution of mosquito vectors should continue to better understand the clinical signs associated with RVFV infection in camels and provide public health authorities an opportunity to anticipate and prepare for a possible RVF outbreak in Khartoum State, Sudan.960.
Mohammed Ahmed UMAR Sho FUKUI Kodai KAWASE Takaharu ITAMI Kazuto YAMASHITA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):281-288
Cardiovascular effects of total intravenous anesthesia using
ketamine-medetomidine-propofol drug combination (KMP-TIVA) were determined in 5
Thoroughbred horses undergoing surgery. The horses were anesthetized with intravenous
administration (IV) of ketamine (2.5 mg/kg) and midazolam (0.04 mg/kg) following
premedication with medetomidne (5 µg/kg, IV) and artificially ventilated.
Surgical anesthesia was maintained by controlling propofol infusion rate (initially 0.20
mg/kg/min following an IV loading dose of 0.5
mg/kg) and constant rate infusions of ketamine (1 mg/kg/hr) and medetomidine
(1.25 µg/kg/hr). The horses were anesthetized for 175 ± 14 min (range
from 160 to 197 min). Propofol infusion rates ranged from 0.13 to 0.17 mg/kg/min, and
plasma concentration (Cpl) of propofol ranged from 11.4 to 13.3
µg/ml during surgery. Cardiovascular measurements
during surgery remained within clinically acceptable ranges in the horses (heart rate: 33
to 37 beats/min, mean arterial blood pressure: 111 to 119 mmHg, cardiac index: 48 to 53
ml/kg/min, stroke volume: 650 to 800 ml/beat and
systemic vascular resistance: 311 to 398 dynes/sec/cm5). The propofol Cpl
declined rapidly after the cessation of propofol infusion and was significantly lower at
10 min (4.5 ± 1.5 µg/ml), extubation (4.0 ± 1.2
µg/ml) and standing (2.4 ± 0.9
µg/ml) compared with the Cpl
at the end of propofol administration (11.4 ± 2.7
µg/ml). All the horses recovered uneventfully and stood
at 74 ± 28 min after the cessation of anesthesia. KMP-TIVA provided satisfactory quality
and control of anesthesia with minimum cardiovascular depression in horses undergoing
surgery. 相似文献