Showing papers by "University of Veterinary Science published in 1997"

Efferent connections of the domestic chick archistriatum: A phaseolus lectin anterograde tracing study

Abstract: The archistriatum of the domestic chick has been implicated in both fear behaviour and learning. However, relatively little is known about its organisation. The efferent connections of discrete anatomical regions of the chick archistriatum were therefore investigated by iontophoresis of the anterograde tracer Phaseolus vulgaris leucoagglutinin into its anterior, dorsal intermediate, ventral intermediate, medial, and posterior parts. The results of this study suggest that the chick archistriatum can be divided into two basic divisions according to whether they project to the following limbic structures: the hippocampal formation, septal areas, lobus parolfactorius, nucleus accumbens, ventral paleostriatum, and dorsomedial thalamus. The limbic archistriatum includes the posterior archistriatum and extends rostrally through the ventral intermediate archistriatum into the anterior archistriatum. The non-limbic archistriatum comprises the dorsal intermediate and medial archistriatum and largely gives rise to specific sensory, somatosensory, and motor telencephalofugal efferents. There may not be distinct borders between these two divisions of the chick archistriatum.

New combination for the therapy of canine otitis externa. I. Microbiology of otitis externa.

Abstract: In order to compound a new drug comblnatlon agalnst canlne otitis externa (OE), 515 dogs affected wlth OE were subjected to physical examlnatlon and mlcroblologlcal analysis of their ear exudates. OE was erythematous-cerumlnous In 83 per cent and suppurative In 17 per cent of the patlent material. Erythematous-cerumlnous lnflammatlons were characterlsed by severe prurltus and accumulatlon of brownlsh, greasy cerumen In the audltory canal. The yeast Malassezla jmchydermat/s was Isolated from the ears of 76 per cent of the dogs, often In comblnatlon wlth Staphylococcus lntermedlus bacterla. M pachydermatls showed the most sensltlvlty, In decreasing order of efflcacy, to ketoconazole, econazole, clotrlmazole, mlconazole and nystatln. S lntermedlus Isolates were most sensltlve to amoxyclllln-clavulanlc acld, enrofloxacln, cephalexln and gentamlcln. The mlcroorganlsm most frequently Isolatcbd from dogs wlth suppurative OE was Pseudomonas aewglnosa; In some cases Proteus, Streptococcus and Pasteurella were also Isolated. The P aeruglnosa Isolates showed the highest sensltlvlty to gentamlcln, polymyxln B and tobramycln.

Human insulin-like growth factor I (IGF-I) produced in the mammary glands of transgenic rabbits: yield, receptor binding, mitogenic activity, and effects on IGF-binding proteins.

Abstract: Insulin-like growth factor I (IGF-I) has acute insulin-like metabolic effects and long-term anabolic actions offering a range of important therapeutic applications. To evaluate a system for large-scale production of this peptide in the mammary glands of transgenic livestock, we generated transgenic rabbits carrying fusion genes in which a synthetic DNA coding for human IGF-I (hIGF-I) was placed under the transcriptional control of regulatory elements isolated from the bovine αS1-casein (αS1-cas) gene. Western blot analysis of milk from αS1-cas-hIGF-I transgenic rabbits demonstrated production of high amounts of mature hIGF-I peptide (7.6 kDa). Quantitative analysis by RIA revealed hIGF-I levels between 50 and 300 μg/ml milk. Recombinant hIGF-I purified from the milk of αS1-cas-hIGF-I transgenic rabbits bound to IGF-I receptors on human IM-9 lymphoblasts and stimulated DNA synthesis by growth-arrested MG-63 human osteosarcoma cells as efficiently as hIGF-I produced in Escherichia coli. Ligand blot analysis...

Changes in Some Red Blood Cell and Clinical Laboratory Parameters in Young and Old Beagle Dogs

Abstract: Routine laboratory and lipid peroxidase parameters in the blood of Beagle dogs under 1 year of age (7 males, 7 females) and over 9 years of age (7 males, 7 females) were compared. The mean corpuscular haemoglobin (MCH) and haemoglobin (Hb) values, plasma total protein (TP) and globulin concentrations in the older dogs were significantly higher than in the younger ones by 13%, 6%, 10% and 15%, respectively. The plasma inorganic phosphate concentration, however, was 30% lower in the older dogs than in the young ones. The concentration of malondialdehyde (MDA) was 30% higher, while the glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities were around twice as high in the older dogs as in the young ones. However, in the older males the concentration of reduced glutathione (GSH) was 43% and in the older females 9% less than in the young ones. Extremely high levels of MDA and low levels of GSH were only found in the older males. GSH-Px and SOD activities were significantly higher in the older male dogs than in the young ones. The activities of these enzymes were highest in the older females. From our results, we suspect that old dogs, especially males, are particularly exposed to the harmful effects of free radicals and lipid peroxidation.

Mercury content of some wild edible mushrooms

Abstract: The mercury (Hg) content of 112 samples of common, wild edible mushrooms was analysed by atomic absorption spectrometry. The average Hg content of all the samples was 1.72 mg/kg dry mass (DM) but the Hg concentrations found in different taxonomic groups (genera and species varied) remarkably. Although different sampling locations obviously have an effect on the Hg concentration of sporocarps, we found evidence for a Hg-accumulating capacity of some taxonomic groups. In addition to Agaricus and Macrolepiota, where the phenomenon of mercury accumulation has already been described, our results indicate high Hg levels in samples of Lycoperdon perlatum (average 2.94 mg/kg DM) and in Lepista species (average 3.02 mg/kg DM). These data confirm the need for greater attention to be given to Hg levels in wild common mushrooms, especially to Hg-accumulating species.

Histopathological changes induced by environmental stress in common carp, Japanese coloured carp, European eel, and African catfish.

Abstract: Histopathological changes caused by stress during catching and transport were examined in four fish species, the common carp (Cyprinus carpio), the Japanese coloured carp (koi, the coloured variant of the Asian carp, Cyprinus carpio haematopterus), the European eel (Anguilla anguilla), and the African catfish (Clarias gariepinus). In all species, the goblet cells of the gills and skin were decreased in number and slight detachment of the epithelium of the secondary gill lamellae was seen. Loss of goblet cells and detachment of the columnar epithelial cells were found in the intestinal mucosa of common carp and coloured carp. It is supposed that these lesions may affect ion transport and respiration in the gills and disturb normal intestinal function, thus serving as a starting point for different diseases.

Efficacy of some pyrethroids against a strain of the rabbit ear mite (Psoroptes cuniculi): an unusual cross-resistance pattern.

Abstract: An in vitro immersion bioassay was used to compare the efficacy of selected pyrethroids against a deltamethrin-resistant strain of rabbit ear mite (Psoroptes cuniculi). A lack of cross-resistance between bromo (deltamethrin) and chloro analogues (cypermethrin) of α -cyano-3-phenoxybenzyl - dihalovinyl-dimethylcyclopropane carboxylate was detected. Whereas deltamethrin proved to be inactive (48-h mortality 21.9% at 1000 mg/kg), each cypermethrin isomer mixture tested, including alpha-cypermethrin [1R(cis) α S + 1S (cis) α R] and theta-cypermethrin [1R(trans) α S + 1 S (trans) α R] and their mixture at a ratio of 4/6, beta-cypermethrin, showed high efficiency (48-h mortality ≥ 95% at 1000 mg/kg).

Attempts to analyse Anguillicola crassus infection and the humoral host response in eels (Anguilla anguilla) of Lake Balaton, Hungary

Abstract: Since the introduction of Anguillicola crassus into Europe, anguillicolosis has been a considerable problem in several countries. From 1991, periodical eel mortality occurred in Lake Balaton, Hungary. However, eels with a worm burden of 20 to 50 parasites did not show severe swimbladder lesions, which observation cast doubts on the primary aetiological role of the parasite in the eel kill. In order to study the pathology of the infection, from the spring of 1996 until October of the same year, 51 eels were collected from two regions of Lake Balaton and examined for swimbladder changes. To detect humoral antibodies, an enzyme-linked immunosorbent assay (ELISA) was performed, using cuticular-oesophageal worm antigen. The results of the test show the applicability of the method. However, no direct correlation was found between antibody levels or the intensity of infection and the swimbladder lesions. The low level of specific antibodies and the increasing severity of swimbladder changes in the autumn suggest that parasite-induced immunity is insufficient to prevent reinfection.

Ultrasonographic study of feline lower urinary tract diseases: 32 cases.

Abstract: The objective of the study was to describe the ultrasonographic findings of urinary bladder urolithiasis and to determine the diagnostic value of the technique in feline lower urinary tract diseases (LUTD). Physical examination of the urinary system and routine clinicopathological analysis of the blood and urine were performed on 32 cats presented with clinical symptoms of LUTD. Cystosonography was done on all of the cats, while plain radiography was performed on 8 and double contrast cystography on 2 cats. Sonography of the bladder provided the following diagnoses: urolithiasis and chronic cystitis: 24 cases, chronic cystitis without urolithiasis: 4 cases, bladder neoplasm: 1 case, negative sonographic finding: 3 cases. Bladder calculi and/or plugs were diagnosed easily, up to a size of 2 mm, according to acoustic shadowing and/or reverberation and gravitation. When the bladder was empty, it was filled up with physiologic saline solution to visualise its contents more easily. Sonography proved to be a useful technique for diagnosing urinary bladder calculi and/or plugs even when they were radiolucent and for distinguishing among the different causes of LUTD. Although ultrasonography is a valuable diagnostic tool, radiography is still necessary to explore lower urinary tract diseases, especially when cystosonography provides negative results or urethral obstruction is suspected.

Diagnostic value of certain mastitis markers in following up the clinical and bacteriological changes in pharmacotherapeutic studies.

Abstract: Trends of certain mastitis markers were studied in udder quarters (n = 201) showing clinical symptoms of acute mastitis. Besides the clinical examination, before the first treatment (baseline sample), and about 3 weeks later, 17 to 24 days following the last treatment (control sample) milk samples were collected for bacteriological identification of the mastitis pathogens and for the determination of certain inflammatory markers: somatic cell count (SCC), N-acetyl-beta-D-glucosaminidase (NAGase) and alpha 1-antitrypsin (ATR) activities, as well as bovine serum albumin (BSA) and chloride (Cl-) concentrations. Based upon the clinical and bacteriological status as well as the SCC recorded at the control investigations, 6 groups were established (recovered, latently infected, subclinical mastitis: bacteriologically positive and negative, as well as clinical mastitis: bacteriologically positive and negative). As compared to the baseline samples, all parameters decreased in the case of recovered udder quarters, as well as in those with abated latent infection or subclinical mastitis at the time of control examination. Comparing the control samples of the different categories, characteristic differences were found in NAGase activity, indicating the grade of cytodamaging effect of mastitis. Of the other markers, ATR and Cl- proved to be more adequate for the differentiation than BSA. It can be concluded that, in addition to SCC, first of all NAGase can be recommended for use as an inflammatory parameter in pharmacodynamic studies. Besides these two parameters, ATR and Cl- can also be chosen as a possible third marker.

Ultrasonographic findings of renal dysplasia in cocker spaniels: eight cases.

Abstract: A retrospective study of eight young Cocker Spaniels aged 9-24 months was performed to describe the ultrasonographic findings of histologically confirmed renal dysplasia Ultrasonography revealed kidneys of significantly (p < 0001) reduced volume in all dogs During qualitative evaluation, two different types of sonographic alterations could be seen In one type of the ultrasound alterations, corticomedullary demarcation was distinct and the renal cortex was remarkably thin, which was best seen in the dorsal (frontal) imaging plane In the other type of the ultrasound appearance, overall increased echogenicity with poor corticomedullary demarcation was noticed, and the kidneys could hardly be separated from their surroundings These features were best recognised in the sagittal (coronal) imaging plane In one dog with secondary hypercalcaemia, a hyperechoic corticomedullary area was also seen Post-mortem histological diagnosis revealed renal dysplasia and secondary fibrosis Based on ultrasound findings alone, renal dysplasia (renal familial disease) can be suspected when small kidneys with thin echogenic cortex are present in young dogs An ultrasound image, similar to that of fibrotic kidneys (increased overall echogenicity and reduced corticomedullary definition) cannot be differentiated from chronic inflammatory disease and from end-stage kidneys Therefore, ultrasound-guided biopsy or post-mortem histology is necessary for the definitive diagnosis of renal dysplasia This is the first study reporting on the ultrasound appearance of renal dysplasia in Cocker Spaniel dogs

Attempts to immunize chickens against Cryptosporidium baileyi with C. parvum oocysts and Paracox(TM) vaccine

Abstract: To study the possibility of immunization against Cryptosporidium baileyi Current, Upton et Haynes, 1986 with the attenuated anticoccidial vaccine, Paracox(TM) and oocysts of C. parvum Tyzzer, 1912, chickens were inoculated orally with either 3 x 10(3) vaccine oocysts or 8 x 10(5) C. baileyi or C. parvum oocysts at 1 week of age. The inoculation with Paracox(TM) vaccine and C. parvum oocysts was repeated at 2 and 3 weeks of age. Uninfected birds served as controls. All animals with the exception of one uninfected group were challenged orally with either 8 x 10(5) C. baileyi or 3 x 10(5) Eimeria tenella Railliet et Lucet, 1891 oocysts at 4 weeks of age. Sera were collected at 4 weeks of age, and were examined by ELISA using C. baileyi antigens. Birds inoculated with C. parvum oocysts did not shed C. parvum oocysts in their faeces, but anticryptosporidial antibodies could be detected in the sera. The total oocyst output of C. parvum inoculated chickens was 17% of that of previously uninfected birds after the oral challenge with C. baileyi. Considering that antibodies play no or only a minor role in resistance to C. baileyi, these results suggest that inoculation of chickens with C. parvum oocysts stimulated also cellular immune response. Based on the relative body weight gain, faecal scores, oocyst output, mortality, and caecal lesions in the birds immunized with Paracox(TM) vaccine and challenged with E. tenella, the vaccination induced only a moderate protection against the reinfection. The results of cross-immunization of chickens with Eimeria spp. and C. baileyi suggest that attenuated anti-eimerian vaccines do not induce any protection against cryptosporidial infection.

New combination for the therapy of canine otitis externa II Efficacy in vitro and in vivo

Abstract: A new, effective drug combination was developed for the therapy of canine otitis externa (OE) by taking into consideration the microorganisms most frequently isolated from dogs affected with OE, their combination, their drug sensitivity and the type and incidence of ear canal inflammation. The antimycotic active ingredient of the combination is ketoconazole, its antibacterial component is gentamicin sulphate, while its antiphlogistic constituent is mazipredone hydrochloride. Based upon the results of in vitro pharmacodynamic tests, the antifungal activity of the combination is superior to that of ketoconazole used alone at the same concentration. A total of 210 dogs affected with OE were treated with the combination: 94.2 per cent of them became clinically symptomless and microbiologically negative in an average of 8.5 days. No adverse reactions were observed in connection with the use of the drug combination. The therapeutic results can be attributed to the high antifungal efficacy of the combination demonstrated in vitro and to the favourable properties of the solvent mixture.

Quantitative two-dimensional echocardiography in the horse: A review

Abstract: Quantitative two-dimensional echocardiography (2DE) was introduced into equine cardiology in the early 1990s. At first, linear and area dimensions and left ventricular volume were validated by the comparison of parameters determined during in vitro 2DE and autopsy measurements. Based on these studies, tomographic planes and intracardiac reference points for in vivo measurements were established and 2DE values have been determined for healthy adult horses by various authors. These data were similar to each other and proved to be comparable with M-mode echocardiography measurements. However, differences in the measured parameters are due to breed and body weight variations of the examined populations, as well as to technical differences between M-mode and 2DE measurement methods. Currently, little information is available on 2DE values in equine cardiac diseases. In one report, 23 horses with aortic insufficiency had significant increases in the mean values of left ventricular chamber size, aortic root diameter and shortening fraction, and left ventricular thickness was also increased. These values were measured by M-mode echocardiography, but diastolic left ventricular enlargement was also measured and illustrated by the use of 2DE. In another study, 38 horses with mitral insufficiency had increased diastolic values of left ventricular and atrial cross-sectional internal diameter.

Adaptive sex-ratio manipulation in Pediculus humanus capitis: possible interpretations of Buxton's data.

Abstract: The sex-ratio pattern of an exceptional population of human head lice (collected in the Colombo Prison, Ceylon, in 1934 to 1936) was found to be consistent with a current hypothesis on adaptive sex-ratio manipulation. Data suggest that the louse burdens were isolated and, therefore, small burdens were inbred. Thus, local mate competition favored females that produced offspring with a female bias. This is the first report to suggest that anopluran lice are capable of adaptive sex-ratio manipulation.

Long term exposure to T-2 Fusarium mycotoxin fails to alter luteal function, follicular activity and embryo recovery in mares.

Abstract: The effect of long term administration of T-2 toxin was studied in 6 Trotter mares during the summer and early autumn. After one complete oestrous cycle (Cycle 1) each mare was given 7 mg purified T-2 toxin per os daily (1 mg/ml in ethyl alcohol) beginning on Day 10 after ovulation in Cycle 2. Exposure to toxin was continued for 32-40 days, until Day 7 of Cycle 4. During this period all the animals remained in good physical condition, but skin lesions were observed around the mouth in 3 cases. Toxin administration had no effect on the length of the interovulatory interval or on the lengths of the luteal and follicular phases. It also had no effect on peripheral plasma progesterone profiles or follicular kinetics, including the growth rate and maximum size of ovulatory follicles and the maximum number, and time of first increase in number, of follicles larger than 1 and 2 cm. Uterine flushing was attempted in 5 mares and yielded 3 embryos (60%). These were of normal size and morphology and one was transferred nonsurgically to a recipient mare; a conceptus developed initially but it subsequently died and was resorbed. The results of the study allowed the conclusion that the administration of 7 mg/day T-2 toxin to mares in good body condition has no detrimental effect on ovarian activity, fertilisation or oviductal transport.

Induction of acrosome reaction in dog sperm by calcium ionophore

Abstract: The sensitivity of the plasma membrane to calcium ionophore (A23187) challenge was studied in dog sperm using fluorescein lectin staining for the assessment of acrosomal status and viability Second fraction ejaculates from 5 dogs were washed, resuspended in Ca(2+)-free (EDTA-treated), 50, 100, 500, 1000 and 2000 microM/l Ca(2+)-containing Sp-TALP medium and induced with 50, 250, 500, 1000, 2500 and 5000 nM/l calcium ionophore Samples were collected from each aliquot after 30 and 60 min of induction to assess the percentage of acrosome reacted sperm cells (AR rate), viability and motility by fluorescein isothiocyanate conjugated peanut agglutinin (FITC-PNA) and ethidium-homodimer combined staining On each slide, 200 sperm cells were assessed under epifluorescence microscope (x 1250) in a blind manner The response to ionophore challenge (AR rate, viability, motility) varied with Ca2+ and ionophore concentration in the suspension A significantly higher AR rate was detected in samples containing 100, 500, 1000 and 2000 microM/L Ca2+ (> 40%) than in that containing 50 microM/L Acrosome reaction could not be successfully induced in the EDTA-treated sample and in any of the aliquots in which 50, 250 and 500 nM/L ionophore concentrations were used for induction Motility decreased drastically in all of the treated samples and stopped in that sample where as significant AR rate could be detected Viability remained high (> 75%) during the incubation and did not differ significantly in the treated and the control groups

Hepatic ultrasonographic findings in experimental carbon tetrachloride intoxication of the dog.

Abstract: An experimental study was undertaken in dogs with carbon tetrachloride (CCl4) intoxication to describe and follow the changes in the ultrasound appearance of the liver. Characteristic ultrasound features (enlarged liver, increased echogenicity with fine, tightly-packed echoes, and loss of echogenicity of the portal vein walls) were seen from day 2 of the experiment, culminating between days 2 and 7. Subsequently the liver gradually and almost completely regained its normal ultrasound appearance. Ultrasonographic findings corresponded to the severity of the clinicopathological parameters, and changed parallel with the results of liver biopsies. Histology of the biopsy samples revealed acute centrolobular lipid accumulation with necrobiosis and necrosis in the hepatocytes in the first stage of the disease. In the second stage, a secondary reparatory-inflammatory process and reparation in the interstitial tissue were seen. In some dogs, ill-defined hyperechoic foci were observed within the liver during the regenerative phase. Hepatic ultrasonography seems to be a reliable and relatively sensitive method for monitoring liver dystrophy with necrobiosis and lipid accumulation and to follow the course of steatosis in clinical cases. Ultrasound-guided biopsy can further improve the diagnostic accuracy of ultrasonography in liver dystrophy.

Changes in blood ionized calcium and some other blood parameters before and after replacement of a left-sided displaced abomasum in dairy cattle.

Abstract: Concentrations in ionized calcium and some other blood parameters including total calcium, magnesium, inorganic phosphate, sodium, potassium, chloride, acid-base and hematological parameters of 15 German Holstein dairy cows were studied before and after surgical replacement of a left sided displaced abomasum. Mild hemoconcentration and hypochloremia were characteristic findings. These parameters tended to become normal within a few days after surgery. Hypocalcemia and low plasma potassium levels were not characteristic in this study, suggesting that hypocalcemia does not play an important role in the initiation of LDA. It can be supposed from this study that the severity of pathological blood findings depends more on the rate of malfunction of the abomasum than on the length of existence of LDA.

The first isolation of Eubacterium suis in Hungary.

Abstract: Eubacterium suis was isolated from the preputium of seven out of 16 mature boars on two farms and from the urinary bladder of one out of five sows originating from a third herd. The morphological and biochemical characteristics of the isolated strains were identical to that of the reference strain of E. suis ATTC 33144. Three out of four strains isolated from Farm A were successfully subcultured aerobically, and then anaerobically again. E. suis together with Proteus mirabilis was isolated from cystitis of a sow 4 days after artificial insemination. These are the first strains of E. suis isolated in Hungary.

Enkephalinergic nerve terminals target inhibitory interneurons in the rat hippocampus

Abstract: USING correlated light and electron microscopic pre-embedding enkephalin immunocytochemistry combined with post-embedding GABA immunogold staining, we found morphological evidence of a direct connection between the enkephalinergic and GABAergic systems in the rat hippocampus. Enkephalin-immunoreactive boutons were found to be presynaptic to GABA-immunoreactive postsynaptic profiles, establishing type 2 symmetrical synapses on GABA-positive cell bodies and dendritic shafts in strata radiatum and lacunosum moleculare of the CA1 region. Thirty-six percent of all studied postsynaptic targets (n = 40) were non-pyramidal, including all somatic (n = 7) and 47% of the dendritic (n = 13) postsynaptic targets. The remaining 64% consisted of pyramidal dendritic shafts and spines. These results support previous physiological experiments suggesting that the opioidergic system takes part in disinhibitory processes in the hippocampal formation.