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1.
Mayr  B.  Schaffner  W.  Botto  I.  Reifinger  M.  Loupal  G. 《Veterinary research communications》1997,21(5):369-373
Highly conserved regions of the tumour suppressor gene p53, including the typical human tumour hot spots (codons 175, 245, 248, 249, 273 and 282), were investigated in various canine neoplasms. A mutation CGG TGG (arginine tryptophan) was detected in codon 249 in an adenoma of the circumanal gland.  相似文献   

2.
Twenty feline neoplasms were sequenced in the region from exons 5 to 8 for the presence of tumour suppressor gene p53 mutations. In a spindle cell sarcoma of the bladder, a missense mutation (codon 164 AAGGAG, lysineglutamic acid) in exon 5 was detected. In a pleomorphic sarcoma, a 23 bp deletion involving the splicing junction between intron 5 and exon 6 was observed. In a fibrosarcoma, a 6 bp deletion of p53 covering 2 bp of exon 7 and 4 bp of intron 7, including the splicing junction, was found. The study demonstrates three new p53 mutations in different types of sarcomas in cats.  相似文献   

3.
The pharmacokinetics of sulphadimidine after a single dose (200 mg/kg i.v.) was studied in five healthy lactating buffaloes. The study revealed that the drug attained its peak concentration of 314.0±13.0, 242.4±3.0 and 100.2±2.5 g/ml at 15 min, 30 min and 12 h in plasma, milk and uterine fluid, respectively. The pharmacokinetic parameters calculated by a 2-compartment open model gave values for t1, t1 and vdarea of 2.10±0.36 h, 12.36±0.57 h and 1.23±0.07 L/Kg, respectively. A high vdarea as well as a value of 0.74±0.08 for K12:K21- (tissue Plasma) indicates better penetration of the drug into the different body fluids and tissues, which is further supported by a high concentration obtained in milk and uterine fluid. The therapeutic concentration (50 g/ml) was maintained for around 24 h in plasma and milk and 12 h in uterine fluid. The results suggest that, apart from its use in systemic infections, the drug can be effectively used by the i.v. route in uterine and mammary gland infections. The dosages for maintaining concentration of 50 g/ml, 100 g/ml and 150 g/ml at convenient dosage intervals of 12 and 24 h were also determined.  相似文献   

4.
The concentration and functionality of the -adrenoceptor (-AR) subtypes in the genital tract of cyclic heifers were investigated. In each tissue sample, a single class of 1-ARs was observed, whereas two distinct classes of 2-ARs were discriminated: low-affinity (LA) and high-affinity (HA) 2-ARs. Statistical analysis showed the presence of significantly (p < 0.05) higher concentrations of all -AR subtypes in the follicle than in the corpus luteum. No significant differences were found in the ovary or myometrium between the luteal and follicular phases. In the ovary, the density of 1-ARs was significantly (p < 0.05) higher than that of 2-ARs. By contrast, there were significantly (p < 0.05) more 2-ARs than 1-ARs in the myometrium. As far as 2-ARs are concerned, LA 2-ARs were significantly (p < 0.05) higher than HA 2-ARs in all tested tissues. Competition studies suggested that the rank order of potency of antagonists for 1-ARs was prazosin > phentolamine > yohimbine, whereas for 2-ARs the order of potency was yohimbine phentolamine > prazosin. Functional assays performed on myometrium showed that noradrenaline, phenylephrine and clonidine elicited concentration-dependent contractions only in dioestrus and pro-oestrus preparations and that clonidine was more effective than phenylephrine as a contractile agent. It appeared that there were no significant modifications in -AR affinity or concentration during the different stages of bovine oestrous cycle, whereas the uterine spontaneous activity and the responsiveness to -adrenergic stimulation was strongly influenced by hormonal levels. The modifications of uterine contractility observed during the oestrous cycle may be related to modifications induced in the transductional mechanisms of -ARs.  相似文献   

5.
This paper reports the milk protein polymorphism, the allele frequencies of variants and the possible linkages among various combinations of milk protein phenotypes in the Kangayam cattle of south India. Milk samples from 156 Kangayam cows were typed by starch gel and polyacrylamide gel electrophoresis for caseins and whey proteins, respectively. All the four milk protein components studied, s1-casein, -casein, -lactoglobulin and -lactalbumin, exhibited polymorphism with high allele frequencies of 0.9231±0.0151 for s1-casein C, 0.9263±0.0148 for -casein A, 0.9135±0.0159 for -lactoglobulin B and a relatively high frequency of 0.6218±0.0275 for -lactalbumin A. The mean heterozygosity estimated over all the four milk protein loci was 0.2420. Genetic equilibrium was observed among all the loci studied, except -lactalbumin. Linkage analysis confirmed the non-independence between s1- and -caseins and between caseins and -lactalbumin phenotypes.  相似文献   

6.
Small intestine was taken from the caudal flexure of the duodenum and the terminal ileum proximal to the ileocaecal fold of 25 horses, 9 with acute grass sickness (AGS), 12 with subacute grass sickness (SAGS) and 12 with chronic grass sickness (CGS). The motility in the samples was measured isometrically either within 1 h of death or after storage for 24 h at 4°C.In control tissue, noradrenaline produced contractions of muscle strips which did not involve a muscarinic cholinergic mechanism and which were unaffected by the 1 antagonist prazosin but were blocked by the 2 antagonist yohimbine. Pretreatment with the antagonist phentolamine prevented the contractile response to noradrenaline and the background contractions either continued at a reduced rate and amplitude or were abolished after a few minutes. Thus, following blockade, noradrenaline reduced the background contraction rate by an effect on inhibitory adrenoceptors. The rate of background contractions in duodenal preparations was significantly greater than that in control ileal preparations.Although cold storage for 24 h caused a reduction in the background contraction rates of the control preparations, there was no effect on the contractile responses to noradrenaline, the associated pharmacology being similar to that of fresh tissue. This suggests that noradrenaline-evoked contraction was not dependent on enteric neural elements.The response to noradrenaline by grass sickness-affected tissue was generally similar to that of tissue from control horses, with an immediate contraction which was 2 sensitive. The contractile response to noradrenaline after propranolol was significantly reduced in the CGS group and there were significant differences between the AGS, CGS and control groups. There was a significant difference between the ileal preparations from the control and SAGS groups in their response to noradrenaline following pretreatment with propranolol.  相似文献   

7.
The synthetic androgen 19-nortestosterone (-NT) has been used illegally as a growth promoter in cattle production in the European Union. Elimination of -NT and its metabolites in plasma, urine and bile was studied in three cattle with cannulated gallbladders following intramuscular injection at a single site of 500 mg of the laurate ester (NTL) containing 300.5 mg -NT. Using enzyme immunoassay quantification, plasma Cmax of free -NT was 0.5±0.15 g/L (mean±SEM). Concentrations of free -NT in plasma were consistently greater than the assay limit of quantification (0.12 g/L) for 32.7±13.42 days. Mean residence time for free -NT in plasma was 68.5±20.75 days. Following sample preparation by immunoaffinity chromatography, high-resolution GC-MS was used to quantify -NT and -NT in urine and bile. -NT was detected irregularly in urine from two of the three animals post injection. The principal metabolite present in the urine, -NT, was detected for 160.3±22.67 days post injection. Cmax for -NT in urine was 13.7±5.14 g/L. Mean urinary AUC0–183 days for -NT was 845.7±400.90 (g h)/L.In bile, -NT was the only metabolite detected for 174.3±8.67 days post treatment. Cmax for -NT in bile was 40.8±12.70 g/L and mean biliary AUC0–183 days for -NT was 1982.6±373.81 (g h)/L. Concentrations of -NT in bile samples were greater than those in urine samples taken at the same time. The mean ratio of biliary:urinary AUC0–183 days was 3.0±0.72. It is concluded that bile is a superior fluid for detection of -NT following injection of NTL, owing to the longer period during which residues may be detected after administration.  相似文献   

8.
The oxidative metabolism of aldicarb (ALD), a carbamate pesticide, and fenbendazole (FBZ), an anthelmintic, was studied using cultured hepatocytes obtained from 4 goats and a bullock and incubated with ALD (50 mol/L) and FBZ (10 mol/L). The parent compounds and the metabolites were measured by HPLC. Both compounds are metabolized at the sulphur atom via two sequential oxidations, first to the sulphoxide (aldicarb sulphoxide and oxfendazole, respectively) and then to the sulphone. Oxfendazole and fenbendazole sulphone from FBZ, and aldicarb sulphoxide from ALD were found in both species. Aldicarb sulphone was not produced by the hepatocyte preparations from the bullock. The good correlation obtained comparing the in vitro results of FBZ metabolism with published in vivo dat obtained on FBZ kinetics in the same species confirmed the usefulness of in vitro models for predictive analysis of in vivo xenobiotic biotransformations.Abbreviations ALD aldicarb - ALDSON aldicarb sulphone - ALDSOX aldicarb sulphoxide - BSA bovine serum albumin - ID internal diameter - EGTA ethylene glycol bis(-aminoethyl ether) N,N,N,N-tetraacetic acid - FBZ fenbendazole - FBZSON fenbendazole sulphone - HBSS Hanks' balanced saline solution - HPLC high-pressure liquid chromatography - LDH lactate dehydrogenase - MFO mixed function oxidase - NCS newborn calf serum - OXF oxfendazole - WME Williams' Medium E  相似文献   

9.
This paper describes a study on the oestrous and ovarian activity and responses to prostaglandin F2 (PGF2) administration and artificial insemination in zebu heifers.Four cycling heifers were artificially infected with 5×106 Trypanosoma vivax organisms. Two heifers served as controls. Two injections of PGF2 were given 11 days apart, commencing at the peak of parasitaemia in the infected animals, followed by artificial insemination 72 and 96 h after the second administration of PGF2. Sera were analysed for progesterone by radioimmunoassay, while ovarian activity and oestrus were determined by rectal palpation and visual observation, respectively. All the infected heifers developed the clinical disease. All control and infected heifers had progesterone profiles consistent with luteolysis and the occurrence of oestrus following the second administration of PGF2. Progesterone levels did not return to normal luteal values in infected animals, however, whilst they did so in control animals. No control or infected heifers became pregnant.The findings suggest that PGF2 will induce a non- fertile oestrus in zebu heifers acutely infected with T. vivax. Re-ovulation is also inhibited within 22 days in a majority of infected animals.  相似文献   

10.
In recent years human and animal cancers have increasingly been shown to have a viral component in their aetiology. Oncogenic viruses will continue to be discovered although with certain cancers there is also an important environmental component, and with others — congenital cancers and cancers of early childhood — an important genetic component. There is thus the probability that cancer may not be an entity. Rather it may be a syndrome, the phenotypic expression of alteration of cellular metabolism, differentiation and cell death. More information is needed on the mathematics of cell division and destruction,in vivo andin vitro, and the involvement of biological clocks, i.e. ageing processes. These data, when available, should help us to understand better the nature of cancer and lead us to more effective methods of prevention and cure.Abbreviations AIDS acquired immunodeficiency syndrome - ALV avian leukosis virus - COFAL complement-fixation test for avian leukosis viruses - FeLV feline leukaemia virus - kb kilobases - L/S viruses leukosis/sarcoma viruses - MMTV mouse mammary tumour virus - MuLV mouse leukaemia virus - wt wild type  相似文献   

11.
Parotid glands from adult dogs were stained with a battery of seven horseradish peroxidase-conjugated lectins (PNA, UEA, LTA, DBA, SBA, WGA and ConA). In some cases (PNA and DBA) neuraminidase digestion was followed by lectin staining. Acinar cells contained conspicuous quantities of oligosaccharides with terminal sialic acid radicals. Galactosil-(13)N-acetylgalactosamine was the most abundant penultimate sugar linked toN-acetylneuraminic acid. Sialylated components having the terminal dimer sialic acid-N-acetylgalactosamine were found in the acinar cells. Secretory cells presented a heterogeneous distribution of glycoconjugates with terminal fucose and -N-acetylgalactosamine. Fucose,N-acetylglucosamine and -N-acetylgalactosamine were present on the apical cytoplasm and surface of the striated and interlobular duct cells. This glycosidic composition was unaffected by extensive selective breeding. The role of abundant amounts of sialic acid radicals in the oral mucosa was considered.Abbreviations HRP horseradish peroxidase - PBS phosphate-buffered saline see also Tables I and III  相似文献   

12.
With electromyography and strain gauges the uterine motility of the sow during the oestrous cycle and early pregnancy was studied. Special attention was paid to characterization of myometrial activity at the time of intrauterine migration of blastocysts.From recordings of 4 animals (3 became pregnant) 3 types of electrical spiking activity (each could be correlated with an elevation of the strain gauge tension) were discerned. Two of them appeared regularly and were suitable for analysis: High Voltage Slow Acticity (with relative high amplitude and low frequency of spikes) and Low Voltage Fast Activity (with relative low aplitude and high frequency of spikes).The sexual status markedly influenced myometrial activity: during prooestrus and oestrus only one type of electrical activity was present whereas the myoelectrical complex (an episode of this activity and the subsequent interval of inactivity) was shorter than 10 min. During dioestrus the myoelectrical complex was longer than 10 min and High Voltage Slow Activity (solely on the cervix and bifurcation) and Low Voltage Fast Activity occurred simultaneously in episodes which mainly appeared to originate on the bifurcation.The characteristics of uterine activity during pregnancy were similar to those of a cyclic sow until day 12. It was only on day 12 that gestation appeared from an increased frequency of myoelectrical complexes.It is concluded that Low Voltage Fast Activity as it was found on the uterine horn at days 8–9 might be involved in the process of intra-uterine migration of blastocysts. In cyclic and in pregnant animals the patterns of Low Voltage Fast Activity were similar. Therefore, the occurrence of Low Voltage Fast Activity is independent of the actual presence of blastocysts. It seems to be exhibited in dependence on the ovarian hormones.  相似文献   

13.
The objective of the experiment was to compare the reproductive post-partum performance of beef cows synchronized for oestrus using prostaglandin F2 (PGF2) alone or with a gonadotrophin-releasing hormone (GnRH)-based drug. Fifty-five post-partum lactating Tuli cows were randomly allocated to three groups. Two groups were synchronized using either two injections of PGF2 (500 g Prosolvin per injection) given 11 days apart (group 1), or GnRH (12.5 g Receptal per injection) followed 6 days later by an injection of 500 g PGF2 (group 2). The cows were bred by artificial insemination 12 h after they were observed in oestrus. Group 3 was synchronized as for group 2, but a second injection of GnRH was given 54 h after the PGF2 injection, at which time the cows were bred by artificial insemination (AI) without detection of oestrus. Blood samples were taken from the cows in group 3 and analysed for progesterone concentration to establish which cows were cycling and in oestrus before and at the time of breeding. Detection of oestrus and breeding by AI was done over 60 days. There were no significant differences (p>0.05) among the three groups in the first service and total conception rates. The percentage of cows in oestrus within 10 days of the synchronization treatment was not significantly different (p>0.05) between groups 1 and 2. The progesterone concentrations in the cows in group 3 showed that only those that were cycling at the start of the experiment responded to the synchronization treatment and conceived after fixed-time breeding. These results suggest that combinations of PGF2 and GnRH may be of value in synchronizing oestrus and controlling breeding in Tuli cows. However, the benefit might be greater if only cows that are known to be cycling are bred in this way.  相似文献   

14.
The purpose of the present investigation was to test the hypothesis that drug-induced changes in rumen contractions influence feed intake in dwarf goats. Intravenous (i.v.) administration of clonidine (1 g kg-1 min-1 for 10 min), xylazine (1 g kg-1 min-1 for 10 min), and PGF-2 (10 g kg-1 min-1 for 15 min) caused bradycardia and inhibition of rumen contractions. However, no appetite-stimulating effect of these drugs was observed. Other clinical changes induced by the 2-adrenergic agonists included slight sedation and a decrease in body temperature; all clinical effects of clonidine and xylazine were partly antagonized by tolazoline pretreatment (10 g kg-1 min-1 for 30 min). These results suggest that the CNS control of feeding differs in ruminants and monogastric species.In dwarf goats fasted for 2 h, i.v. administration of oxytocin (0.01 IU kg-1 min-1 for 15 min), vasopressin (0.01 IU kg-1 min-1 for 15 min), octapressin (0.003 IU kg-1 min-1 for 15 min) or PGE (0.8 g kg-1 min-1 for 15 min) did not change feeding behaviour during the two observation periods (0–30 min and 180–210 min after drug infusion, respectively). In previous studies, similar doses of these drugs induced changes in heart rate and inhibition of rumen contraction in goats. These findings demonstrate that drug-induced changes in forestomach contractions do not simply cause changes in feeding behaviour. The i.v. infusion of the PGF2 analogues etiproston (10 g kg-1 min-1 for 15 min), luprostiol (30 g kg-1 min-1 for 15 min), cloprostenol (1 g kg-1 min-1 for 15 min) and tiaprost (1 g kg-1 min-1 for 15 min) induced hypophagic effects and stimulated intestinal propulsion.  相似文献   

15.
Pathogenic mechanisms of caprine arthritis-encephalitis virus   总被引：1，自引：0，他引：1  
Goats infected with caprine arthritis-encephalitis virus (CAEV) show chronic arthritis and cachexia, which are progressive in nature. The immunopathogenic mechanisms responsible for these progressive clinical symptoms have not been fully elucidated. Various haematological and immunological parameters were evaluated in experimentally-infected goats showing typical signs of CAEV-induced disease. Infected goats showed recurrent lymphocytosis that may be due to constant presentation of antigen by infected cells of a monocyte/macrophage lineage. The serum alkaline phosphatase and -glutamyl transferase concentrations were elevated in infected goats, a characteristic of hepatic and bone disorders. All other serum chemistry parameters were similar between infected and control goats. Importantly, the serum tumour necrosis factor- (TNF-) levels were higher in infected goats. The cachexia seen in infected goats may be at least partly due to altered metabolism as a result of prolonged elevation of serum TNF- levels. Depressed natural killer cell activity was observed in infected goats and may contribute towards the establishment of a persistent infection with CAEV.Abbreviations AIDS acquired immunodeficiency syndrome - CAEV caprine arthritis-encephalitis virus - GGT -glutamyl transferase - HBSS Hanks' balanced salt solution - HIV human immunodeficiency virus - NK natural killer - PBMC peripheral blood mononuclear cells - PCR polymerase chain reaction - SAP serum alkaline phosphatase - TNF tumour necrosis factor  相似文献   

16.
Diseases caused by lymphoid leukosis virus (LLV), a retrovirus, take a long time after infection to develop and have a wide variety of pathological manifestations. This long latent period is characteristic of persistent virus infections. Disease produced by LLV infection and its underlying mechanisms is compared with persistent infections caused by other retroviruses in birds and mammals of veterinary importance. The diseases considered for comparison are those caused by reticuloendotheliosis, feline leukaemia, bovine leukosis and equine infectious anaemia viruses. There are significant changes in the immunological status in all diseases caused by these viruses. LLV infections follow this trend with, in manifestations of neoplastic disease, a perturbation of the normal switch that occurs from IgM to IgG synthesis. There are also indications of other immunological disturbances.Factors other than immunological disturbances may contribute to the length of time after infection required for the many forms of LLV infection to appear. Such additional factors may include the operation of biological clocks, such as the arrival of sexual maturity, and also the very nature of retroviruses. These factors, like the immunological changes, play major roles in the maintenance and progression of persistent retrovirus infections.Abbreviations ACTH adrenocorticotropic hormone - AEV avian erythroblastosis virus - AMV avian myeloblastosis virus - BLV bovine leukaemia virus - CAV chicken anaemia virus - EBL enzootic bovine leukaemia - EIAV equine infectious anaemia virus - env envelope gene - FeLV feline leukaemia virus - FeSV feline sarcoma virus - FOCMA feline oncovirus membrane-associated antigen; gag, group antigen gene - HTLV human T-cell leukaemia virus - LLV lymphoid leukosis virus - L/S leukosis/sarcoma - LTR long terminal repeat - MAV myeloblastosis-associated virus - MDV Marek disease virus - MuLV mouse leukaemia virus - ORF open reading frame; pol, polymerase gene - REV reticuloendotheliosis virus - RIF resistance-inducing factor - RSV Rous sarcoma virus  相似文献   

17.
Stress, stressors and the stress response are terms which represent concepts rather than oeing precisely definable. No single theory of stress has been universally accepted. Selye's General Adaptation Syndrome of stress remains the primary theory for the basis of stress research in food-producing animals; however, other concepts and theories have been developed. This paper reviews current theories and suggests that the complexity of research on stress in food-producing animals can be attributed to the lack of concrete theories and concepts regarding identifiable stressors, the endocrine responses stimulated by potential stressors and the complex and integrated biological changes in the neuro-endocrine system resulting from exposure to hypothesized stressors.  相似文献   

18.
A trial was carried out in 1-day-old broiler chicks raised for 54 days in floorpens under simulated commercial conditions, but isolated from all extraneous virulent coccidial infections, to demonstrate the safety of Paracox attenuated vaccine administered at the recommended dose when chicks were 7 days old. The vaccine did not adversely affect the water consumption, faecal moisture or litter condition of the broilers. Recycling of the attenuated coccidia occurred in vaccinated birds, oocysts being present in the litter between 5 and 33 days after vaccination; a single peak of oocysts was detectable 5 or 12 days after vaccination. Unvaccinated medicated control birds did not produce oocysts, indicating freedom from both between-pen contamination by the vaccine and invasion of the chicken-house by extraneous coccidial infection. A small proportion (4%) of vaccinated birds had mild coccidial lesions when sampled at 26, 33 or 40 days after vaccination. Despite this, the vaccinated birds performed better than control (unvaccinated, nicarbazin-treated) birds and there was no post-vaccinal check in their weight gain. Their mean finishing weight was 10.4% greater, their food conversion ratio 7.2% lower and their mortality 44.4% lower than the unvaccinated control birds, reflecting the safety of Paracox vaccine.Abbreviation FCR food conversion ratio  相似文献   

19.
A pharmacokinetic study of ampicillin (6 mg/kg intravenous) revealed that the peak concentrations of 17.81±1.25, 5.64±2.24 and 1.09±0.10 g/ml of the drug were attained at 15 min, 30 min and 2 h in plasma, milk and uterine fluid respectively. A therapeutic concentration of 0.1 g/ml was maintained from 15 min–8 h, 15 min–6 h and 30 min–6 h in plasma, milk and uterine fluid. Hence, the drug may be used effectively in mammary gland and uterine infections apart from its use in other systemic infections.  相似文献   

20.
The number of -motoneurons in the spinal cord segments C6 to Th2 of five calves with Arthrogryposis Multiplex Congenita (AMC) and of five normal calves was compared. A statistically highly significant reduction in the number of -motoneurons in segment C6 was observed in the affected calves. Two hypotheses to explain the effect of these findings were proposed. Firstly, it was thought that AMC may result from paresis of some muscles of the girdle, shoulder and elbow. Secondly, it was postulated that the decrease in the number of -motoneurons in C6 may have induced a radial nerve dysfunction resulting in AMC.This work was supported by the IWONL, Brussels, Belgium.  相似文献   

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