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1.
A number of immuno-competent Blackface lambs were infected with 10,000Haemonchus contortus third stage larvae and were later challenged with a second dose of 10,000H. contortus third stage larvae. One group of lambs was treated with dialysed transfer factor prior to the second challenge dose.Histological changes in the abomasal wall, reductions in abomasal worm burdens at slaughter and faecal egg counts monitored throughout the experiment suggested the presence in some animals of (1) an innate resistance, (2) a self curing effect, (3) an enhancement of this self curing effect in the transfer factor treated group and (4) a response in one transfer factor treated animal comparable to classical self cure.  相似文献   

2.
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   

3.
Persson Waller, K., Colditz, I.G., Flapper, P. and Seow, H.-F., 1997. Leukocyte and cytokine accumulation in the ovine teat and udder during endotoxin-induced inflammation. Veterinary Research Communications, 21 (2), 101-115The accumulation of leukocytes, ovine serum albumin and the cytokines interleukin-1 (IL-1), tumour necrosis factor- (TNF-), interleukin-8 (IL-8), granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon- (IFN-) was studied during endotoxin-induced inflammation in lactating and dry ovine udders, and in the teat cisterns of dry ewes after surgical closure of the passage between the teat and udder cisterns. Samples were taken before infusion and hourly up to 10 h after infusion of 0.1, 1 or 10 µg of endotoxin, or infusion of pyrogen-free saline (PFS) as a control. Rectal temperatures were measured.A significant dose- and time-dependent accumulation of leukocytes, mainly neutrophils, was observed in the lactating udders and in the teat cisterns. In the dry udders, the leukocyte accumulation was significant for time but not for dose. Peak numbers of cells were reached at 3-4 h in the dry udders and in the teat cisterns, but not until 10 h after infusion in the lactating udders. The changes in the ovine serum albumin concentrations mostly paralleled changes in leukocyte numbers.A role was indicated for TNF-, IL-8 and GM-CSF, but not for IL-1 and IFN-, during endotoxin-induced inflammation in the ovine udder. Release of TNF-, IL-8 and GM-CSF was most prominent in lactating udders, peaking at 2 or 3 h after infusion, but was also detected in dry udders and teat cisterns. Detectable levels of IL-1 and IFN- were occasionally found in all three groups.  相似文献   

4.
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   

5.
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   

6.
Infectious pancreatic necrosis (IPN), first described in 1955, is a viral disease of salmonid fry. The virus remains in the sexual fluids of adult carriers, thus allowing vertical transmission. The virus has been classified among the reoviruses, and at least three serotypes are well known: VR299 (USA), Sp and Ab (Europe). It has been established in the case of VR299 virus that some IPN survivors carry high levels of antibodies and completely eliminate the virus, while others do not synthesise antibodies and remain carriers for life. Sp type virus serially passaged a few times on cultured trout cells (RTG2), acquires new properties compared to the wild original virus. The adapted virus forms large plaques, loses its pathogenicity and is neutralised by normal serum from trout free of IPN. The molecule involved in this neutralisation is not related to IgM antibodies, and its nature remains unknown. Variant virus types with different growth characteristics have also been selected from VR299 cultured in trout (RTG2) or minnow (FHM) cells. It appears therefore necessary to investigate the relationships betweenin vitro properties and pathogenicity.
Kurzfassung Die zuerst in Amerika (1955) beschriebene infektiose Pankreas-Nekrose (N.P.I.) stellt eine Virose der Salmonidenbrut dar. Der Virus befindet sich in den sexuellen Ausscheidungen erwachsener Trägertiere; somit ist eine vertikale Ubertragung möglich. Von diesem Virus, der zur Familie der Reoviridae gehört, sind wenigstens drei Serumtypen bekannt: VR299 (USA), Sp und Ab (Europa). Für VR299 steht fest, dass die NPI Uberlebenden viele Antikörper erzeugen und den Virus völlig ausscheiden, während andere Varianten gar keine Antikörper produzieren und daher lebenszeitige Träger bleiben. Auf kultivierte Forellenzellen übertragene Viren des Sp Typus erlangen andere Eigenschaften als die Zellen des wilden Original virus. Der angepasste Virus provoziert grössere Auflösungsplatten, verliert seine pathogene Wirkung und wird vom normalen Forellenserum der NPI neutralisiert. In diesem Fall gehört das verantwortliche Molekül für die Neutralisierung nicht zu den IgM Antikörpern, und seine Natur ist nicht gut bekannt. Eine Selektion verschiedener Viren mit unterschiedlichen Wachstumseigen-schaften hat man mit dem VR299 auf Forellen-oder Pfrillen-(FHM)-Zellen erhalten. Es scheint demnach notwendig, die Beziehungen zwischen Eigenschaftenin vitro und die Pathogeneität näher zu untersuchen.
Resume Décrite pour la première fois aux U.S.A. en 1955, la Nécrose Pancréatique Infectieuse (N.P.I.) est une virose des alevins de salmonidés. Le virus est présent dans les produits sexuels des porteurs adultes, assurant la transmission verticale. Ce virus, classé dans la famille des Reoviridae, présente au moins trois sérotypes: VR299 (U.S.A.), Sp et Ab (Europe). Classiquement, les survivants de N.P.I. (dans le cas du VR299) font beaucoup d'anticorps et éliminent le virus, ou bien font peu ou pas d'anticorps et restent porteurs à vie. les virus de type Sp cultive sur cellules de truite RTG2 acquièrent en quelques passages des propriétés différentes de celles du virus sauvage d'origine. Le virus adapté provoque des plages de lyse plus grandes, perd tout pouvoir pathogène et est neutralisé par le sérum de truites indemnes de N.P.I. Dans ce cas, la molécule responsable de la neutralisation n'appartient pas aux anticorps, et sa nature reste mal connue. La sélection de variants possédant des caractéristiques de croissance différente a aussi été obtenue avec le VR299 propagé en cultures soit de truit (RTG2) soit de vairon (FHM). Il apparaît donc néssaire d'approfondir les relations entre propriétésin vitro et pouvoir pathogènein vivo.
Riassunto Descritta negli USA per la prima volta nel 1955, la necrosi pancreatica infettiva e una virosi dei giovani salmonidi. Il virus e presente nei prodotti sessuali dei portatori adulti, assicurando la trasmissione verticale. Questo virus classificato nella famiglia dei Reoviridae, rappresenta almeno tre sierotipi diversi: il VR299 (USA), lo Sp ed il Ab (Europa). Tipicamente, i sopravissuti della NPI, producono molti anticorpi ed eliminano il virus, oppure ne producono pochi o non ne procucono affatto e rimangono portatori a vita. Dopo alcuni passaggi, i virus di tipo Sp, coltivati su cellule di trota RTG2, acquistano delle proprietà diverse delle cellule del virus selvatico di origine. Il virus adattato provoca dell placche di lisi più grandi, perde ogni potere patogeno, e si neutralizza con il siero di trota indenne da NPI. In questo caso, la molecola responsabile della neutralizzazione non appartiene agli anticorpi e la sua natura resta poco nota. La selezione di varianti con caratteristiche di crescita diverse è stata anche ottenuta propagando il VR299 in colture di trota (RTG2) e di vairone (FHM). Appare quindi necessario approfondire le relazioni tra le proprietain vitro e il potere patogenoin vivo.
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7.
Residues of dimetridazole in eggs after treatment of laying hens   总被引：1，自引：0，他引：1  
Laying hens were dosed orally with dimetridazole (DMZ) (50 and 250 mg/kg) for 3 days or intramuscularly (50 mg/kg), also for 3 days, and the residues were determined by liquid chromatography in albumen and yolk. The sensitivity of the whole procedure was 2 ng/g. The drug was excreted preferentially into the yolk (about 57% of the total) and the elimination period lasted for 4–6 days after treatment.Abbreviations AUC area under the plasma concentration-time curve - depletion time the time needed for the DMZ concentration to fall below 0.01 g/g - elimination rate constant - Cl clearance - DMZ demetridazole  相似文献   

8.
Factor XI (F XI) deficiency is an autosomal recessive coagulopathy found in Holstein cattle. Affected animals have a 50% greater prevalence of repeat breeding. Therefore, several parameters describing ovarian function were studied. Daily blood sampling revealed that progesterone concentrations were slower to decline from a peak at day 16 (p<0.01) to values less than 3 nmol/L in F XI-deficient cows (5.14±0.69 days (mean ± SD) versus 4.05±0.63 days in control animals), resulting in an oestrous cycle length of 24.7±2.1 days compared to 22.9±3.0 days, respectively. This was not due to an alteration in the availability of prostaglandin F2 (PGF2) or oxytocin (OT) involved in luteolysis. No significant differences (p>0.05) were seen between normal (n=7) and F XI-deficient (n=7) cows in the peak values or the area under the curve for the pulse in 13,14-dihydro-15-keto PGF2 in response to OT challenge or in the parameters describing the pulse of ovarian OT secretion after PGF2 injection (n=7 for each) between days 12 and 14. Ovulatory follicular development was assessed by ultrasound monitoring and plasma 17-oestradiol values at 8-h intervals after a luteolytic injection of cloprostenol (n=6 for each). Follicular diameter was smaller (p<0.05) and accompanied by lower peak oestradiol values near the time of ovulation in F XI-deficient cows. The results suggest that the oestrous cycle in F XI-deficient cows is characterized by a slower process of luteolysis that may be associated with smaller follicular development.Abbreviations F XI factor XI - OT oxytocin - PGF2 prostaglandin F2 - PGFM 13,14-dihydro-15-keto-prostaglandin F2 - i.m. intramuscularly  相似文献   

9.
Seven lambs were fed a mixture of bog plants containing 15 g (wet matter)Narthecium ossifragum per kg live weight for 10 consecutive days. Their serum creatinine concentration increased from day 1 to 4 but then fell to normal by day 6 after feeding started. In the same animals, the serum magnesium concentration was increased on days 3, 4 and 5. Histopathological examination of the kidneys of 2 lambs killed after being fed 25 gN. ossifragum per kg live weight for one day revealed tubular epithelial cell degeneration and necrosis. There were no signs of disease or distress in the experimental animals and their appetite remained normal throughout the experimental period. It was concluded thatN. ossifragum is probably nephrotoxic to lambs.Abbreviations ALP alkaline phosphatase - ASAT aspartate aminotransferase - -HBA -hydroxybutyric acid - CK creatine kinase - d.m. dry matter - -GT -glutamyltransferase - GLDH glutamate dehydrogenase - MCV mean cell volume - RBC red blood cells - SEM standard error of the mean - WBC white blood cells - w.m. wet matter  相似文献   

10.
The effect of an intravenous bolus injection of endotoxin, 0.1, 1 or 10 g/kg, on rectal temperature, clinical appearance, haematological parameters, and on gastrointestinal electrical activity was examined in 11 conscious piglets of 4–5 weeks of age, with implanted electrodes in the antrum pylori, duodenum, jejunum and ileum. All doses resulted in a significant and dose-dependent increase in rectal temperature, in pronounced clinical signs and in distinct changes in haematological values. These included shivering, depression, respiratory distress, a leukopenia (0.1 g/kg) or a leukocytosis (1 g/kg) with a shift to the left, an accelerated sedimentation rate and a decreased packed cell volume. Doses of 1 and 10 g/kg induced a transient inhibition of gastroduodenal electrical activity. These results suggest that, in the piglet, endotoxin primarily manifests general clinical signs and that the gastrointestinal effects coincide with these.  相似文献   

11.
In human medicine it has been shown that the bromocresol green (BCG) dye-binding method for the determination of serum albumin is not entirely specific, the dye reacting also with certain human serum globulins. This causes over-estimation of albumin when reaction times are prolonged beyond 30 seconds.In the present study, serum albumin values obtained from three animal species by the immediate, i.e. less than 30 seconds, BCG reaction were compared with those by the 10-minute BCG reaction. Albumin-depleted sera were prepared using an affinity chromatography technique and their reactions and those of purified gamma globulin preparations with the dye were studied.In cattle, sheep and horses, serum albumin values obtained by the 10-minute reaction were higher than those obtained by the immediate BCG reaction, the differences being statistically significant. Purified gamma globulin did not react with the BCG dye after 10 minutes, but other globulins did. There were differences between the species in the magnitude of the reaction of their globulins with BCG dye.  相似文献   

12.
The effects of novobiocin (range 0.0125–2 mmol/L) on the hydroxylation of testosterone, the N-demethylation of erythromycin, and the glucuronidation of -naphthol and paracetamol were studied using pig hepatic microsomes, pooled from five animals. The final concentrations of these substrates in the incubation mixtures were selected to meet Vmax conditions. Novobiocin caused a concentration-dependent inhibition of the glucuronidation of paracetamol; the formation of -naphthol-glucuronide was reduced to a lesser degree. These results confirm and extend earlier findings in laboratory animal species that novobiocin inhibits UDP-glucuronosyltransferases (UDPGTs). Moreover, novobiocin strongly inhibited 6-hydroxylation of testosterone. The microsomal N-demethylation of erythromycin and hydroxylation of testosterone at the 15 position were less affected by novobiocin. These results suggest that novobiocin inhibits not only UDPGTs, but also cytochrome P450 (CYP) enzyme activities, probably those belonging to the CYP3A subfamily. More research is needed to reveal which CYPs and UDPGTs are affected by novobiocin in vivo, in order to improve the understanding and probably the predictability of potential drug interactions with this antibiotic.  相似文献   

13.
The morphology of the erythrocyte cell series was investigated in external jugular vein blood samples from Dwarf and Danish Landrace goats aged from one day to 12 months. Three erythrocytic cell types were observed in neonates after supravital staining with new methylene blue. The first type were macrocytes which were stained uniformly dark to muddy blue. They formed the majority of the erythrocytic cells at birth and were categorized as diffusely basophilic chromatophilic erythrocytes. The second type were punctate and aggregated reticulocytes, and the type were mature erythrocytes. The size ranges of the three erythrocytic cells were 4.2–5.6, 4.9–6.3 and 2.8–3.5 m diameter respectively in the Dwarf kids and 5.6–9.7, 4.2–9.0 and 3.8–4.2 m respectively in the Landrace kids during the first week of life. Romanowsky-stained blood smears from neonatal kids were characterized by anisocytosis and poikilocytosis in which polychromatophilic macrocytes were numerous, but reticulocytes were not clearly identifiable. The ranges of erythrocyte diameters in Romanowsky-stained neonatal blood films were 4.4–5.8 (5.2±0.39) and 4.1–6.7 (5.1±0.67) m in Dwarf and Landrace kids respectively, decreasing to 3.0±0.15 and 3.3±0.13 m in the two broods respectively by 12 months of age. The numbers of diffusely basophilic polychromatophilic erythrocytes and punctate/aggregated reticulocytes diminished with age and they were not observed in 1–2-month-old kids.  相似文献   

14.
Fenclor 64 (a PCB's commercial mixture) was administered twice i. p. to virgin and pregnant New Zealand rabbits at the dose of 100 mg/Kg to evaluate its inducing properties on the following hepatic microsomal MFO activities: p-nitro-anisole-O-demethylase, amino-pyrine-N-demethylase, acetanilide-hydroxylase and arylhydrocarbons-hydroxylase.The results indicate that Fenclor 64 evoked a mixed type induction in virgin as well as in pregnant rabbits since it increased liver weight, cytochrome P-450 levels, as well as p-nitro-anisole-O-demethylase and acetanilide-hydroxylase. Pregnancy by itself affects only amino-pyrine-N-demethylase levels.Work supported by a grant from M. P. I. 40% (1982)  相似文献   

15.
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   

16.
A review of the literature on intestinal atresia of domestic animal species and humans was done. The 5 types of intestinal occlusions described in human infants are atresia type 1, atresia type 2, atresia type 3, stenosis, and the apple peel or Christmas tree deformity. The intestinal defects described in domestic animal species such as the bovine, equine and porcine are similar to those of human infants. The T-formation, an intestinal defect of the bovine resembling atresia type 3, and rectal stricture, an acquired intestinal defect of the porcine resembling stenosis, were described recently. Intestinal atresia is similar in several species and these similarities raise the questions as to whether the pathogenic mechanism and possibly etiologies of intestinal atresia are similar in these species.  相似文献   

17.
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   

18.
The pathogenicity and immunosuppressive properties of two field isolates of infectious bursal disease virus (IBDV) and five commercial IBDV live virus vaccines marketed in India were evaluated in this study. The pathogenicity of the wild type viruses and vaccines were based on mortality, the bursa:body weight ratio and microscopic lesions in the bursa in 3-week-old chicks that received these viruses. The immunosuppressive effects of these viruses were evaluated by measuring the antibody responses to sheep red blood cells, Brucella abortus plain antigen and Newcastle disease virus (NDV) vaccine in one-day-old chicks. One field isolate (N35/93) was found to be more pathogenic and immunosuppressive than the other (N45/92) while none of the commercial mild Lukert type vaccines were found to be pathogenic. One of the vaccine strains marked as Mild Lukert type was highly immunosuppressive; one was moderate and one could be classified as mild. Both the intermediate vaccines tested were highly immunosuppressive.  相似文献   

19.
The kinetic profiles of norfloxacin were evaluated in afebrile, febrile and probenecid pre-treated (70 mg/kg orally) febrile goats after a single intravenous (i.v) dose (5 mg/kg). Fever was induced and maintained for 12 h by injecting Escherichia coli endotoxin (0.2 g/kg, i.v.) and repeating it in half the dose (0.1 g/kg) 5 h later. The plasma pharmacokinetic values for norfloxacin were best represented using a two-compartment open model. The peak norfloxacin plasma level of 90.52±3.18 g/ml attained in the probenecid pre-treated febrile goats was higher than that in the febrile (75.46±0.72 g/ml) or afebrile goats (62.25±1.23 g/ml). ClB and K el values were significantly (p<0.01) decreased in febrile compared with afebrile goats. These values were further reduced in febrile goats after probenecid pre-treatment. However, t 1/2 was not affected by the fever-probenecid interaction. Norfloxacin may be used as an infusion with probenecid in caprine diseases where very high plasma levels are required to combat resistant organisms such as Bacteroides.Abbreviations MIC minimum inhibitory concentration - LPS lipopolysaccharide - i.v. intravenous(ly)  相似文献   

20.
Haematological estimations and serum biochemical analyses were made on 100 samples collected from clinically healthy Hijin racing camels (Camelus dromedarius) in Kuwait. The red blood cell counts, packed cell volume, haemoglobin concentration, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and total white blood cell counts were estimated. In the serum biochemical analyses, sodium, potassium, iron, calcium, phosphorus, magnesium, total bilirubin, blood urea nitrogen, creatinine, glucose, total protein and cholesterol concentrations were measured, as were the alanine aminotransferase, aspartate aminotransferase, -glutamyltransferase, creatine kinase and alkaline phosphatase activities. The results are discussed in relation to other findings reported in camels.  相似文献   

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