bluuebunny/crossref_metadata_2025 huggingface dataset:
A Light and Transmission Electron Microscope Study of a Black Locust Tree, Robinia pseudoacacia (Fabaceae), Affected by Witches’‐Broom, and Classification of the Associated Phytoplasma
Authors: Chapman G. B. , Buerkle E. J. , Barrows E. M. , Davis R. E. , Dally E. L.
Published: March 2003

Light and transmission electron microscopy of phloem sieve‐tube elements, companion cells, and parenchymal cells in thin and ultrathin sections of small and medium rachises and small, medium and large leaflets of a black locust tree, Robinia pseudoacacia L., affected by witches’‐broom disease revealed (in the small and medium rachises and leaflets) structures that were characteristic of phytoplasmas, and crystal‐like inclusions in the phloem sieve‐tube members. A crystal‐like inclusion was also seen in a companion cell. Paracrystalline arrays were seen only (and very rarely) in phloem sieve‐tube elements of medium rachises. Some elements contained several crystal‐like inclusions and each inclusion had fracture planes. The crystal‐like inclusions and paracrystalline arrays apparently have not been previously reported in the black locust. The paracrystalline arrays and crystal‐like inclusions may merely be by‐products of the plant’s metabolic activity. Extensive additional work would be required to establish the precise relationship (if any) of the arrays and inclusions to the black locust, witches’‐brooming and/or phytoplasmas. Results from analysis of 16S rRNA gene sequences amplified by the polymerase chain reaction indicated for the first time that the phytoplasma associated with black locust witches’‐broom is a member of group 16 SrIII (peach X‐disease) phytoplasma group. This raised the question of whether black locust may be a significant source of the phytoplasma for infection of other plants, especially agricultural crops.
Infection of Subterranean Clover (Trifolium subterraneum) by Kabatiella caulivora
Authors: Bayliss K. L. , Kuo J. , Sivasithamparam K. , Barbetti M. J. , Lagudah E. S.
Published: March 2003

Kabatiella caulivora is a serious pathogen of clover (Trifolium) spp. Subterranean clover (T. subterraneum) cv. Woogenellup was inoculated with K. caulivora, to study the attachment and germination of conidia, germ‐tube penetration of the plant surface, and histochemistry and ultrastructure of changes in the host associated with lesion development. The foliar architecture caused the conidia to concentrate at the base of leaflets and on the petiolules (between the leaflets and petioles). Epidermal cells immediately beneath conidia and, occasionally, also adjacent cells developed a yellow‐brown discoloration 1 day post‐inoculation. Penetration appeared to be directly through the cuticle, characterized by constricted hyphae at the point of entry. No appressoria were observed. In leaves, invasion was restricted to the area proximal to the petiolule and leaf mid‐rib. In petioles and petiolules, the hyphae initially remained between the epidermal cells and first layer of mesophyll cells before moving intercellularly through the mesophyll tissue towards phloem tissues. The cuticle was occasionally degraded in petiole and petiolule infections, the loss of epidermal and mesophyll cell wall components was detected, and chloroplasts and starch grains were disrupted. Plants developed macroscopic symptoms 10–11 days post‐inoculation with necrotic lesions occurring on leaves, petioles and petiolules. Sporulation occurred approximately 15–18 days post‐inoculation when affected plants collapsed. This information may be useful for breeding programmes aimed at selecting varieties with improved resistance to the clover scorch disease.
Identification of Orchid fleck virus by Reverse Transcriptase‐Polymerase Chain Reaction and Analysis of Isolate Relationships
Authors: Blanchfield A. L. , Mackenzie A. M. , Gibbs A. , Kondo H. , Tamada T. , Wilson C. R.
Published: March 2003

Using reverse transcription‐polymerase chain reaction (RT‐PCR) tests with a primer complementary to a region of its nucleoprotein gene together with a polydT/SP6 primer, Orchid fleck virus (OFV) was detected in 34 samples of infected orchids of several different genera from world‐wide sources. The resulting DNA fragments were approximately 800 bp in length and their sequences were determined directly. Analysis of sequences of the major open reading frame (ORF) within the DNA fragments obtained showed the presence of two virus strains. The first group was of two isolates, the original Japanese isolate from which the primers were derived and one from Germany, and the second group contained 33 isolates from four continents. The sequences of different groups differed from one another by at least 15.6% (nucleotide) and 1.8% (amino‐acid), but the within‐group differences were much less (<1.7% difference). A search of the international nucleotide database with the OFV sequences showed them to be related, but distantly, to nucleoprotein regions of the genomes of four plant‐infecting rhabdoviruses.
Occurrence of European Stone Fruit Yellows Phytoplasma (ESFYP) Infection in Peach Orchards in Northern‐Central Italy
Authors: Pollini C. Poggi , Bissani R. , Giunchedi L.
Published: March 2003

During field surveys in 1999 and 2000 of peach orchards in Northern‐Central Italy, plants of different cultivars were observed with symptoms of early leaf reddening, abnormal thickening of midribs and primary veins, autumnal growth of latent buds which produce tiny chlorotic leaves and sometimes flowers, and early phylloptosis; such symptoms, rarely seen previously on peach, are associated with European stone fruit yellows phytoplasma (ESFYP). In the orchards inspected, 1–4% of trees were affected and most were grafted on cv. G.F. 677. In most of the symptomatic samples (130 of 157 tested), only ESFYP was detected using different diagnostic methods [4′,6′‐diamidino‐2‐phenilindole, 2HCl (DAPI), polymerase chain reaction (PCR) with ribosomal and non‐ribosomal primer pairs, PCR‐enzyme‐linked immunosorbent assay, nested‐PCR]. The immunoenzymatic detection of PCR products with a pathogen‐specific probe ensured fast, sensitive and specific detection of ESFYP. This is the first survey to assess the occurrence of phytoplasmas in peach orchards in Northern‐Central Italy.
Aspects of the Biology of Ustilago kamerunensis, a Smut Pathogen of Napier Grass (Pennisetum purpureum)
Authors: Farrell G. , Simons S. A. , Hillocks R. J.
Published: March 2003

The smut Ustilago kamerunensis causes serious losses in biomass to Pennisetum purpureum, an important fodder crop in East Africa. Descriptions of symptoms in infected plants, and the morphology and size of fungal spores and sori agreed with those of the original record. Spores in soil remained viable for up to 16 weeks under ambient conditions, and were able to germinate at temperatures between 0 and 35°C in the laboratory. Sporidia and germ tubes were produced from spores on agar surfaces, but appressoria resulted from germinating spores on host plant surfaces. The infection court was the germinating tiller bud.
Histological and Ultrastructural Changes in Leaves and Stems of Resistant and Susceptible Chickpea Cultivars to Ascochyta rabiei
Authors: ILARSLAN H. , DOLAR F. S.
Published: March 2003

The histo‐ and cytopathological effects in resistant (ILC‐195) and susceptible (Canitez‐87) chickpea cultivars were examined by light, transmission and scanning electron microscopy 3, 5 and 7 days after inoculation (d.a.i) of seedlings with Ascochyta rabiei. The fungus produced typical appressoria that penetrated both cuticle and stomata. The resistant plants had physical barriers and a cuticle layer against fungal penetration 3 d.a.i. The fungus spread intercellularly and subepidermally in the leaves and stems of susceptible plants 3 d.a.i., and was followed 5 d.a.i. by cell plasmolysis, degeneration of organelles and of cellulose, but not lignified, walls. Pycnidia formation occurred between 5 and 7 d.a.i. 7 d.a.i., organelle degeneration, pycnidia formation and symptom severity increased. Tracheidal elements, including lignified elements, were almost intact in both resistant and susceptible cultivars. In the susceptible plants, lignin cell walls were slightly degraded after 7 days. There was less cell degeneration and pycnidia formation in resistant plants. Some electron‐dense large bodies and lipid granules were observed within intracellular fungal hyphae in infected cells of resistant plants 7 d.a.i.
Incidence, Aggressiveness andIn PlantaInteractions ofBotrytis cinereaand other Filamentous Fungi Quiescent in Grape Berries and Dormant Buds in Central Washington State
Authors: Dugan F. M. , Lupien S. L. , Grove G. G.
Published: March 2003

Recovery of quiescent filamentous fungi from non‐symptomatic grape berries and dormant buds demonstrated dominance ofAlternaria,Aureobasidium,Cladosporium,Ulocladiumand other dematiaceous hyphomycetes. Up to 78% of berries contained fungi prior to harvest.Botrytis cinereawas recovered from 0.2 to 0.5% of surface‐disinfested berries just subsequent to fruit set, and 1.6–4.8% of surface‐disinfested, over‐wintered dormant buds. In laboratory inoculations of mature grape berries with strains ofAlternaria,Aureobasidium,Cladosporium,UlocladiumandBotrytis, only the latter was aggressive in rotting berry fruits. Inoculations withB. cinereaalone and in combination with strains ofAlternaria,Aureobasidium,CladosporiumandUlocladiumrecovered from grape demonstrated that prior occupation of wound sites by the latter fungi resulted in reduced lesion size compared to inoculation withB. cinereaalone.
Cloning and Sequence Analysis of the Eburicol 14 α‐Demethylase Encoding Gene (CYP51) from the Japanese Pear Scab Fungus Venturia nashicola
Authors: Cools H. J. , Ishii H. , Butters J. A. , Hollomon D. W.
Published: March 2003

The slow growth of many filamentous fungi in vitro prevents rapid isolation of large quantities of genomic DNA, thereby hampering molecular studies. Using a polymerase chain reaction (PCR)‐based adapter ligation cloning technique that requires only nanogram quantities of genomic DNA we have successfully cloned the complete CYP51 gene encoding the eburicol 14α‐demethylase, the target for DMI (Demethylation‐inhibiting) fungicides, from the Japanese pear scab fungus, Venturia nashicola. Analysis of predictedamino acid sequences of CYP51s from strains less sensitive to DMIs revealed no alterations when compared to the sensitive reference strain.
The Extracellular Proteases Secreted in vitro and in planta by the Phytopathogenic Fungus Sclerotinia sclerotiorum
Authors: Billon‐Grand G. , Poussereau N. , Fèvre M.
Published: March 2003

The proteolytic enzymes secreted by Sclerotinia sclerotiorum were characterized using mechanistic inhibitors, affinity chromatography and analytical electrophoresis. The proteolytic system mainly constituted of acidic proteases but a neutral protease (serine protease) was also found at the initial stage of plant infection by the fungus. In vitro and in planta protease profiles were shown to be similar. Properties of the enzymes produced were matched with the ambient pH indicating that the set of enzymes secreted reflected the environmental niche created during mycelial growth.
Potato Cell Plasma Membrane Receptors to Ring Rot Pathogen Extracellular Polysaccharides
Authors: Romanenko A. S. , Lomovatskaya L. A. , Shafikova T. N. , Borovskii G. B. , Krivolapova N. V.
Published: March 2003

The interaction of extracellular polysaccharides (EPS) of the potato ring rot bacterial pathogen Clavibacter michiganensis ssp. sepedonicus (Spieck. et Kott.) Skaptason et Burkh. (Cms) with protoplasts isolated both from leaf cells of plants grown in vitro and microsomal membrane fractions obtained from cell suspension cultures of two potato (Solanum tuberosum L.) cultivars contrasted by their resistance to this pathogen was studied. The EPS intensively bind to protoplast surfaces and microsomal membranes of the susceptible cultivar but not to those of the resistant cultivar. Treatment with protease, excess of unlabelled EPS, and with dextran, did not lead to the binding of fluorochrome‐labelled EPS to protoplasts and microsomal membranes (from both cultivars). It is proposed that (a) a great number of receptors to EPS Cms are present in the plasma membranes of potato cells of susceptible cultivars, (b) these receptors contain proteinaceous sites exposed on the external side of the plasma membrane which participate in EPS binding, and (c) the plasma membranes of cells of resistant cultivars contain a small but sufficient quantity of receptors to EPS able to induce defensive responses in plants.
Occurrence of Verticillium fungicola var. fungicola on Agaricus bitorquis Mushroom Crops in Spain
Authors: Gea F. J. , Tello J. C. , Navarro M. J.
Published: March 2003

Diseased fruit bodies of Agaricus bitorquis, with similar symptoms to those caused by dry bubble on Agaricus bisporus, were observed in some Spanish crops during summer 1999. Isolates of Verticillium fungicola from A. bitorquis and A. bisporus were submitted to different temperatures and to prochloraz–Mn sensitivity tests. All the isolates collected from A. bitorquis and A. bisporus were identified as V. fungicola var. fungicola. Artificial infections of A. bisporus and A. bitorquis with V. fungicola var. fungicola are also described in the present study. The appearance of natural infections of V. fungicola var. fungicola in A. bitorquis crops could well be due to the growing temperatures used in Spain, which are considerably below those used in other countries.
Comparison of Sedative Effects of Medetomidine‐Midazolam,. Acepromazine‐Butorphanol and Midazolam‐Butorphanol in Dogs
Authors: Kojima K. , Nishimura R. , Mutoh T. , Takao K. , Matsunaga S. , Mochizuki M. , Sasaki N.
Published: March 2003

Sedative effects of medetomidine at 20 μg/kg and midazolam at 0.3 mg/kg (MM), acepromazine at 0.05 mg/kg and butorphanol at 0.2 mg/kg (AB), and midazolam at 0.1 mg/kg and butorphanol at 0.2 mg/kg (MB) were compared in dogs. All dogs given MM were laterally recumbent within 11 min of the administration of the drugs, and this combination also induced deep sedation accompanied by analgesia and muscle relaxation, and strongly depressed arousal reactions to external stimuli. However, undesirable effects such as bradycardia and decreased respiration were also observed in dogs given MM. Six of seven dogs given AB were laterally recumbent within 16 min of the administration of the drugs, and this combination induced relatively deep sedation but only a mild depression of arousal reactions to external stimuli. MB induced mild or moderate sedation with relatively large differences in effects among individuals. The recovery from sedation in each group was smooth and total recovery times were not significantly different.
A Study of Lipid Peroxidation and Vitamin E in Dairy Cows with Hepatic Insufficiency
Authors: Mudroň P. , Rehage J. , Qualmann K. , Sallmann H. ‐P. , Scholz H.
Published: March 2003

Sixteen dairy cows were studied to assess the status of the natural antioxidant vitamin E and lipid peroxidation in their livers. Cows with liver failure (n = 7) showed clinical signs of a hepatic encephalopathy and had the following values of selected blood indices: AST > 80 U/l and GLDH > 15 U/l in serum, and venous plasma ammonia > 35 mmol/l. The control group (n = 9) consisted of dairy cows which were recovering from surgery (omentopexy) and were free of any health complications. Blood was analysed for α‐tocopherol, aspartate aminotransferase, glutamate dehydrogenase, γ‐glutamyl transferase, total bilirubin, ammonia, cholesterol, albumin, free fatty acids, glucose, and β‐hydroxybutyrate. Alpha‐tocopherol, triglyceride and malondialdehyde were measured in wet liver tissue. The cows with hepatic failure were clearly low in α‐tocopherol and had significantly lower (P < 0.01) plasma α‐tocopherol than the controls. Both liver triglycerides and MDA were higher (P < 0.05) in the cows with fatty livers. It is concluded that the cows with liver failure had an increase in the intensity of hepatic lipoperoxidative processes and a low antioxidative status, which should be taken into consideration in cases where treatment of the disease is proposed.
Production of Reactive Oxygen Species in Neutrophils after Repeated Bouts of Exercise in Standardbred Trotters
Authors: Korhonen P. A. S. , Lilius E.‐M. , Hyyppä S. , Räsänen L.A. , Pösö A. R.
Published: March 2003

Six trained Standardbred trotters exercised on a racetrack on 2 days with a 3‐day interval. On both exercise days the horses trotted three different exercise bouts with increasing intensity with 60‐min intervals. Exercise‐induced stress was manifested as leucocytosis, an increase in the neutrophil : lymphocyte (N : L) ratio, and increased capacity to produce reactive oxygen species in the peripheral blood as indicated by an increase in whole blood chemiluminescence. The leucocytosis was mainly due to neutrophilia, which lasted for 6 h. Production of reactive oxygen species per single neutrophil showed no significant change during a day of exercise, but was lower on the second exercise day. The cortisol concentrations and N : L ratio, used as indicators of stress, behaved differently: Cortisol did not change significantly after exercise, whereas the N : L ratio increased. These results suggest that in trained horses, the N : L ratio is a sensitive indicator of stress of short duration, and an attenuated N : L response can be taken as an indicator of adaptation to exercise stress.
Effects of Vitamin E and Different Energy Sources on Vitamin E Status, Milk Quality and Reproduction in Transition Cows*
Authors: Baldi A. , Savoini G. , Pinotti L. , Monfardini E. , Cheli F. , Orto V. Dell
Published: March 2003

We investigated whether vitamin E supplementation and supplemental energy sources (fat or starch) influenced plasma and milk levels of vitamin E, and reproductive and other parameters in 28 Italian Friesian multiparous dry cows. From 14 days before expected calving to 7 days after, the animals were assigned to either basal diet (containing 1000 IU/day of vitamin E) or an extra 1000 IU/day of vitamin E (total 2000 IU). In addition they received either 0.5 kg/day of corn or 0.2 kg/day of calcium soaps. Plasma samples were collected 4 days before expected calving and 4 days after calving and analysed for α‐tocopherol and cholesterol. Milk yield as well as the composition, somatic cell count (SCC) and α‐tocopherol of milk were determined 7 and 14 days after calving. Milk yield and composition were unaffected by treatments. SCC was significantly lower in (SCC Log 4.62 versus Log 5.1,P< 0.01) 2000 IU/day animals than in the 1000 IU/day group. Milk α‐tocopherol was higher (P< 0.001) in animals receiving 2000 IU/day (1.11 vs. 0.65 µg/ml,P< 0.01). Plasma α‐tocopherol in animals receiving 2000 IU/day was also higher (P< 0.001) than in cows receiving 1000 IU/day (4.85 vs. 3.25 µg/ml), but was not affected by dietary energy source. Number of services and days to conception were lower (P< 0.01) in the 2000 IU vitamin E supplemented cows. To conclude, dietary vitamin E supplementation to periparturient dairy cows increased plasma and milk vitamin E, decreased SCC in milk, and improved fertility but different energy sources had no effect on any measured variable.
Effects of Sevoflurane, Isoflurane and Halotane Anaesthesia on Fluorescein Angiographic Phases of Dogs: A Comparative Study
Authors: Martín E. , Redondo J. I. , Molleda J. M. , Santisteban J. M. , López R. , Gómez‐Villamandos R.
Published: March 2003

A fluorescein angiography method was developed to compare the onset and the total duration of the fluorangiographic phases between three anaesthetic protocols in six healthy mixed‐breed dogs. The animals were anaesthetized three times. Each dog received, as pre‐anaesthetic protocol, atropine (10 μg/kg intramuscularly), and as a sedative, romifidine (80 μg/kg intravenously). Fifteen minutes later, induction of anaesthesia was delivered with propofol (1 mg/kg intravenously) and maintained either with sevoflurane (SEVO group), isoflurane (ISO group) or halothane (HAL group) for 30 min in all cases. Some angiographic, cardiovascular and respiratory variables were registered during the procedure. Recovery times were also registered. Angiographic variables recorded were: onset of the arterial phase (TA), onset of the arteriovenous phase (TAV), onset of the venous phase (TV), complete arterial phase duration (I1), complete arteriovenous phase duration (I2) and I1plus I2(I3). Mean heart rate, mean arterial pressure, systolic arterial pressure, diastolic arterial pressure, respiratory rate, tidal volume, arterial oxygen saturation and end‐tidal CO2during SEVO and ISO anaesthesia, were similar in dogs. Minute ventilation and rectal temperature were higher in dogs with SEVO than ISO. HAL produced higher arterial pressures and a lower arterial oxygen saturation than ISO and SEVO. Mean respiratory rate, rectal temperature and minute ventilation were higher in HAL. Pulse rate, end‐tidal CO2and tidal volume were similar in the dogs of the three groups. No differences in recovery times were found. The fluorescein angiographic times were within the normal range. There were no significant differences between protocols in I1, I2or I3. HAL produced a significant increase of all temporal variables (TA, TAV and TV) when compared with ISO; TA was higher in HAL than SEVO‐treated dogs. All protocols appear to be safe and effective for inducing and maintaining general anaesthesia in healthy dogs for performing fluorescein angiography.
Visceral Botulism – A New Form of Bovine Clostridium botulinum Toxication
Authors: Böhnel H. , Schwagerick B. , Gessler F.
Published: March 2003

There are reports of a hitherto unknown bovine disease in Germany. The symptoms are, in general, indigestion (constipation alternating with diarrhoea), non‐infectious chronic laminitis, engorged veins, oedemas, retracted abdomen, emaciation and apathy. Most cases occur during the peripartal period and often result in unexpected death. In addition, there are findings of delayed growth and wasting in heifers, as well as decreasing milk yield. Clinical and standard laboratory examinations leave the origin undisclosed. Bioassays for Clostridium botulinum, its spores and toxins in animals of affected farms revealed the presence of free botulinum toxin in the contents of the lower sections of the intestine. In two control farms without signs of the disease, the tests remained negative. This seems to support our hypothesis that long‐lasting absorption of low quantities of botulinum toxin may interfere with the neurological control of intestinal physiology. The authors propose to name this disease complex ‘visceral botulism’.
Use of the Flexion Test of the Distal Forelimb in the Sound Horse: Repeatability and Effect of Age, Gender, Weight, Height and Fetlock Joint Range of Motion
Authors: Busschers E. , Van Weeren P. R.
Published: March 2003

The flexion test of the distal limb is a commonly used clinical tool in both lame and sound horses. In the latter use it is given some predictive value. In recent studies it has been shown that examiner‐related factors (force, time) may strongly influence the outcome of the test. In the present study, the possible influences of a number of horse‐related factors and short‐ and long‐term repeatability were investigated. Flexion tests were performed by the same researcher in 100 clinically sound horses under standardized conditions. The outcome of the test was scored on a 9‐point semiquantitative scale. The maximum flexion angles of the fetlock joints were measured and the range of motion (ROM) of the fetlock joint was calculated. In the second part of the study, flexion tests were repeated, at intervals of 10 min, 30 min, 48 h and 6 months in 23 horses to assess repeatability. Over 60% of the 100 sound horses had a positive flexion test. Of these, about 50% showed a slight lameness, 35% a mild lameness, and 15% a distinct lameness. There was no influence of weight, height or ROM on the score of the flexion test. The outcome of the flexion test increased significantly with age and was significantly higher in mares than in geldings. When repeating the flexion test with short intervals of 10 and 30 min, the score increased significantly after the second test. Repeated flexion after 48 h did not result in a significantly different outcome. Over a 6‐month period, the outcome of the test decreased significantly and the ROM increased significantly. It is concluded that most clinically sound horses have a (slightly) positive flexion test of the distal limb. This and the lack of long‐term consistency of the test cast doubt on the presumption that a positive flexion test may be an indication for subclinical joint disorders and question the possible value of the test as a predictor of future joint‐related problems. There exists a wide individual variation in ROM of the fetlock joint with, in sound horses, no relationship between ROM and the outcome of the flexion test. The factors age and gender should be taken into account when interpreting the results of a flexion test.
Plasma Gastrin Activity and the Diagnosis of Bleeding Abomasal Ulcers in Cattle
Authors: Ok M. , Sen I. , Turgut K. , Irmak K.
Published: March 2003

The present study was designed to evaluate the usefulness of plasma gastrin determinations as a diagnostic aid and to review the clinical and haematological findings in cattle with bleeding abomasal ulcers. Twenty‐nine cows with bleeding abomasal ulcers and six healthy cows were used. Clinical and laboratory examinations, including plasma gastrin levels, were performed. Anorexia, depression, dark‐coloured to black faeces, pale mucous membranes, abdominal pain, moderate tachycardia and tachypnoea were the most pronounced clinical symptoms in the cattle with bleeding abomasal ulcers. Plasma gastrin concentration was significantly higher (P < 0.05) in the cattle with bleeding abomasal ulcers than in healthy cows. The mean plasma gastrin concentration in healthy cattle was 103.2 pg/ml, while the mean plasma gastrin concentrations in cattle with bleeding abomasal ulcers were found to be 213.6 pg/ml. Haemoglobin levels, packed cell volume, total white blood cell count and mean corpuscular volume were significantly lower (P < 0.05) in the cows with bleeding abomasal ulcer than in the healthy cattle. The results of this study show that measurement of plasma gastrin can be useful in the diagnosis of bleeding abomasal ulcers in cattle.
Serum Keratan Sulphate as a Cartilage Metabolic Marker in Horses: the Effect of Exercise
Authors: OKUMURA M. , KIM G. H. , TAGAMI M. , HARAMAKI S. , FUJINAGA T.
Published: March 2003

Keratan sulphate (KS) concentration in sera from resting horses and horses training daily on a racetrack was measured by an inhibition enzyme‐linked immunosorbent assay (ELISA) using anti‐equine KS antibody 1/14/16H9. For the in‐training horses, serum KS concentrations in 2‐year‐old‐horses was significantly higher than 3‐ or 4‐year‐old‐horses. A higher concentration of serum KS was found in the in‐training group than in the long‐term resting group in 2‐year‐old‐horses. Serum KS concentration increased remarkably immediately after training in healthy horses, and at 1, 5, 9 and 24 h after training remained at similar levels to the pre‐training concentration. The results suggest that serum KS concentration could represent the situation of joint loading, induced by daily racetrack training, affecting the metabolic activities in joint cartilage.
Bile Acid Extraction Rate in the Liver of Cows Fed High‐Fat Diet and Lipid Profiles in the Portal and Hepatic Veins
Authors: Mohamed T. , Sato H. , Kurosawa T. , Oikawa S.
Published: March 2003

The purposes of this study are to assess the responses of increased supplemental dietary fat in the cow, without upsetting rumen fermentation, on the bile acid (BA) extraction rate in the liver and to determine whether this diet would affect the postprandial lipid profiles in the portal and hepatic venous blood. Six Holstein cows were equipped with catheters fitted in the portal and hepatic veins. Two cows each were assigned randomly to a sequence of three dietary treatments of 21‐day period. The methodology of this study was based on the supplementation of the basal concentrate diet with 0 (control), 5, or 10% calcium salts of fatty acids (CSFA). The total bile acids were significantly increased in the portal and hepatic veins with the 5% CSFA diet, whereas no increase occurred with the 10% CSFA diet. Data obtained in this study showed that 10% CSFA diet failed to stimulate BA secretion to exceed the values obtained with 5% CSFA‐diet. Moreover, there was no change in the hepatic extraction rate of BA in animals fed either the 0 or 5% CSFA diets which ranged from 2.4 to 6.5‐fold and 3.1 to 7.3‐fold, respectively. However, the extraction rate increased sharply with the 10% CSFA diet (27‐fold). The median portal and hepatic concentrations of total lipids, triglycerides, total cholesterol, phospholipids and non‐esterified fatty acids did not show any significant increase during feeding of the control diet. Moreover, feeding either the 5 or 10% CSFA diet did not significantly increase these values in either vein.
Mucopolysaccharidosis VI in a Siamese/Short‐Haired European Cat*
Authors: Macrì B. , MARINO F. , MAZZULLO G. , TRUSSO A. , DE MARIA R. , AMEDEO S. , DIVARI S. , CASTAGNARO M.
Published: March 2003

A 3‐year‐old Siamese/short‐haired European cat was referred for clinical disease characterized by dwarfism, facial dysmorphia, paralysis, small and curled ears, corneal clouding and large areas of alopecia. X‐ray examination showed multiple bone dysplasia. On the basis of clinical features a form of mucopolysaccharidosis was suspected. The cat, killed at the owner's request, presented several severe skeletal deformities such as long caudal limbs, enlarged thorax with sunken breastbone, vertebral ankylosis in many spinal segments and visceral involvement. Histologically, the cat showed diffuse vacuolization and enlargement of cells in cartilage, bone and visceral organs. Ultrastructurally, membrane‐bound vacuoles were filled with fibrillar and fluffy‐material or concentrically whorled lamellae. Arylsulphatase B activity was 3.24 nm/mg/h in the affected cat and 30.6 in a normal age‐matched control (NC). The l‐iduronidase activity was slightly increased. Quantitation of total glycosaminoglycans (GAGs) revealed a 4.5‐fold increase in the affected cat as compared with NC, while electrophoretic run of specific GAGs [chondroitin sulphate (CA); hyaluronan (HA); heparan sulphate (HS); dermatan sulphate (DS); keratan sulphate (KS)] performed on a cellulose acetate sheet, showed a striking increase in the DS band. On densitometric analysis of the electrophoretic run stained with Alcian Blue 8GX, the absorption of DS was eight‐fold increased as compared with NC. The clinical and morphological features, and the biochemical findings, were consistent with the diagnosis of feline mucopolysaccharidosis VI.
Field Evaluation of a Live Vaccine against Porcine Reproductive and Respiratory Syndrome in Fattening Pigs
Authors: Mavromatis I. , Kritas S. K. , Alexopoulos C. , Tsinas A. , Kyriakis S. C.
Published: March 2003

A live vaccine based on a European isolate of porcine reproductive and respiratory syndrome virus (Porcilis PRRS) was tested in this study in order to determine the protection of fattening pigs against the respiratory form of the syndrome under field conditions. Ten thousand pigs in an infected farm were vaccinated against PRRS virus at the age of 6 weeks and were compared with non‐vaccinated pigs with respect to their health status, mortality, performance parameters (average daily gain, average daily feed intake, feed conversion ratio) and the presence of certain pathogens in their lungs. The results showed that treated pigs became ill less frequently and demonstrated reduced mortality compared with untreated ones. As compared with non‐vaccinated animals, PRRS‐vaccinated pigs also performed in a better way with respect to the feed conversion ratio (P < 0.05) and average daily gain (P < 0.05), while feed intake was similar for both groups (P > 0.05). Bacteriological examinations of the lungs revealed increased incidence of respiratory bacterial infection in untreated pigs compared with treated ones. A tendency for a faster antibody response was also detected in the vaccinees. The results of the present study show that immunization with a live vaccine does protect fattening pigs against the respiratory manifestations of PRRS.
Airborne Gram‐Negative Bacterial Flora in Animal Houses
Authors: Zucker B.‐A. , Trojan S. , Müller W.
Published: March 2003

The concentration and the species composition of airborne gram‐negative bacteria were studied in four cattle houses, one pig house and one poultry barn. On average only between 0.02 and 5.2 % of the total number of culturable aerobic bacteria were identified as gram‐negative bacteria. Obligate anaerobic gram‐negative bacteria were not isolated at all. In the airborne gram‐negative bacterial flora the following bacterial families dominated: the Enterobacteriaceae, the Pseudomonadaceae and the Neisseriaceae. Within the family of the Enterobacteriaceae the species Escherichia coli and Enterobacter agglomerans were predominant. In animal houses using straw as bedding material Ent. agglomerans was most frequent, whereas in animal houses without litter E. coli was mainly found. Airborne Neisseriaceae were isolated very frequently in cow barns with Acinetobacter lowffii as the primary species. Airborne Pseudomonadaceae were found in high concentrations during periods of high air humidity. The results presented may also give some indications on the origin and sources of airborne endotoxins in animal housing.
The Ability of the Enzyme‐Linked Immunosorbent Assay to Detect Antibody againstStaphylococcus aureusin Milk following Experimental Intramammary Infection
Authors: Fox L. K. , Adams D. S.
Published: March 2003

Changes in the milk antibody levels againstStaphylococcus aureuswere measured at the start of an experimental intramammary instillation of eitherS. aureus(Study I) orStaphylococcus hyicus(Study II). A commercial enzyme‐linked immunosorbent assay system was used. Twenty‐one Holstein cows were enrolled in Study I and 15 Holstein cows were used in Study II. Pathogen instillation began 21 days before the start of the non‐lactating period. Cows received intramammary antibiotic treatment in all quarters immediately after the last milking, the start of the non‐lactating period. Lacteal secretions were collected before the start of the non‐lactating period, and during the immediate postpartum period in both studies, and during the non‐lactating period in Study I. Milk was cultured for mastitis pathogens andS. aureusantibody levels and somatic cell counts were determined from all samples. There was an approximate 2‐week delay in the elevation in antibody levels in response to the instillation ofS. aureus. Antibody levels remained elevated in cows withS. aureusintramammary infections postpartum, but were below threshold in cows where intramammary infections were cured during the non‐lactating period. Antibody levels were elevated byS. hyicusintramammary infections, remained elevated for the first 12 days postpartum, but were below threshold by day 21 postpartum. Cows with incipient intramammaryS. aureusinfections might be misclassified as false negatives by the antibody test. However, results suggest that cows withS. hyicusintramammary infections that were not cured would not be misclassified if milk is withheld from test for the first 30 days postpartum, as recommended by the manufacturer of the test.
Type‐ and Subtype‐Specific RT‐PCR Assays for Avian Influenza A Viruses (AIV)
Authors: Starick E. , Rømer‐Oberdørfer A. , Werner O.
Published: March 2003

Reverse transcriptase (RT) PCR assays have been developed to improve the diagnosis of avian influenza A. RT‐PCR using primers complementary to a conserved region of the matrix protein was assessed as being suitable for the detection of influenza A virus RNA from poultry as well as from pigs, horses and humans, regardless of the haemagglutinin (HA) and neuraminidase (NA) subtype. Therefore, this RT‐PCR is a valuable tool to confirm the initial diagnosis of any influenza A infection.

As a second approach, experiments were performed to identify the HA gene encoding the post‐translational cleavage site of potentially highly pathogenic AIV isolates by RT‐PCR. The principal aim was to design one universal primer pair for each virus subtype, H5 and H7, respectively, which allows the detection of all strain variants using only one consistent method. To realize this objective, it was necessary to develop ‘wobble’ primers. AIV RNAs from seven H5 and 11 H7 subtype viruses included in the investigations were specifically recognized by RT‐PCR using these primers. This method therefore provides a rapid, subtype‐specific diagnosis and subsequent sequencing of H5 and H7 avian influenza viruses.
Immune Reactions in Cattle after Immunization with aMycobacterium paratuberculosisVaccine and Implications for the Diagnosis ofM. paratuberculosisandM. bovisInfections
Authors: Köhler H. , Gyra H. , Zimmer K. , Dräger K. G. , Burkert B. , Lemser B. , Hausleithner D. , Cußler K. , Klawonn W. , Heß R. G.
Published: March 2003

After immunization of four calves with a live modifiedMycobacterium paratuberculosisvaccine the course of the humoral and cell‐mediated immune reactions was studied during a 2‐year clinical investigation. Furthermore, the possibility of shedding of the vaccine strain and the influence of the vaccination on the tuberculin skin test was determined. In addition to standard procedures recently developed diagnostic methods (antibody enzyme‐linked immunosorbent assay, interferon‐γ test, polymerase chain reaction) were used. A cell‐mediated immune reaction, reflected in an increased, specifically induced, interferon‐γ production developed much earlier (1–2 weeks post‐immunization) than humoral immunity (8–16 weeks post‐γ immunization). While the increase in antibody titres was transient, declining to extremely low levels 48–60 weeks post‐immunization, cell‐mediated immunity remained detectable until the end of the investigation. Spread of the vaccine strain into the body and shedding were never detected during the whole course of the study except for one colon site in one calf. As late as 2 years after vaccine application positive or doubtful skin reactions againstM. bovispurified protein derivative were measured, reflecting possible interference of the immunization with the diagnosis of bovine tuberculosis. At the end of the investigation, a positive cell‐mediated immune reaction was also detected in the control animal although clinical, pathological and bacteriological examinations gave no indication for a mycobacterial infection.
Comparison of 16 Chelonid Herpesviruses by Virus Neutralization Tests and Restriction Endonuclease Digestion of Viral DNA
Authors: Marschang R. E. , Frost J. W. , Gravendyck M. , Kaleta E. F.
Published: March 2003

A total of 16 chelonid herpesviruses that were isolated between 1992 and 1998 were compared with one another on the basis of serology and restriction enzyme digestion patterns of viral DNA. The viruses stem from tortoises of three different species in four different European countries and the United States of America. The majority of the isolates were similar to one another. One isolate, however, differed strongly from all others both serologically and in the restriction cleavage pattern of its DNA, showing that there are at least two different sero‐ and genotypes of herpesviruses that infect tortoises.
Flow Cytometric Analysis of Mitogen‐Induced Activation of Rainbow Trout (Oncorhynchus mykiss) Peripheral Blood Leucocytes
Authors: Scharsack J. P. , Steinhagen D. , Leibold W. , Rabe U. , Körting W. , Schuberth H.‐J.
Published: March 2003

Proliferation of rainbow trout peripheral blood leucocytes in vitro is usually assessed by measuring incorporated tritiated thymidine. In this report we monitored the in vitro proliferative response to the mitogen Concanavalin A (Con A) by means of flow cytometry (FCM) and 3H‐thymidine incorporation. When analysed by FCM, blood leucocytes displayed two main cell populations with distinct forward and side scatter (FSC/SSC) characteristics: lymphocytes with low FSC/SSC values and non‐lymphoid leucocytes (NLL) with increased FSC/SSC values. The nature of these cell types were confirmed by microscopy. Interestingly, the FSC/SSC pattern of lymphocytes remained unchanged after in vitro stimulation with Con A, whereas cells from the NLL population showed a marked shift towards increased FSC values. In stimulated cultures, the increase of FSC values of the NLL population significantly correlated with contemporarily measured 3H‐thymidine incorporation (r=0.7, P < 0.001). The mitogenic response of blood leucocytes originating from different individual fish varied over wide ranges. It was found to be related to the numbers of NLL present in the leucocyte sample. The present results show that qualitative and quantitative FCM analysis of morphological parameters (FSC/SSC) of blood leucocytes makes it possible to discriminate between leucocyte populations of the rainbow trout and to monitor cell proliferation experiments.
The Occurrence of Pathogenic Listeria monocytogenes and Antibodies against Listeriolysin‐O in Buffaloes
Authors: BARBUDDHE S. B. , CHAUDHARI S. P. , MALIK S. V. S.
Published: March 2003

The occurrence of Listeria monocytogenes in meat and milk samples, and antilisteriolysin O (ALLO) antibodies in sera of buffaloes were studied. Isolation of the pathogen was attempted from the samples by selective enrichment in University of Vermont Medium and plating onto Dominguez–Rodriguez isolation agar. The pathogenicity of the isolates was tested by Christie, Atkins, Munch Petersen test and mouse inoculation test. Of 167 meat samples 2.4 and 10.17% were positive for L. monocytogenes and Listeria sp., respectively. Of the 64 milk samples 6.25 and 26.13% were positive for L. monocytogenes and Listeria sp., respectively. A total of 284 serum samples were tested by listeriolysin O (LLO)‐based indirect enzyme‐linked immunosorbent assay of which 25.35% were found to be seropositive. The culture positivity for L. monocytogenes and detection of ALLO did not show any agreement (κ=0.035). The prevalence of pathogenic L.monocytogenes in milk and meat and the occurrence of anti‐LLO antibodies is of concern from the public health point of view.
Aetiology and Histopathology of Bovine Mastitis of Espontaneous Occurrence
Authors: Benites N. R. , Guerra J. L. , Melville P. A. , da Costa E. O.
Published: March 2003

Infectious bovine mastitis is responsible for serious economic losses in dairy cattle breeding. Information about the damages caused by micro‐organisms is of great interest and importance. The purpose of the present study was to report on the microbiological and histopathological aspects of the mammary parenchymas of slaughtered dairy cows. A total of 184 mammary glands were examined and samples of mammary parenchyma were collected for microbiological and histopathological examinations. Micro‐organisms were isolated from 69.6% samples; 23 (12.5%) of the 184 samples did not show histological changes; inflammatory response was observed in 56 (30.4%) samples; inflammatory response and repair were present in 82 (44.6%) samples; repair process was verified in 23 (12.5%) of the mammary glands. Coagulase‐negative Staphylococci were observed in 53.8% of the samples followed by coagulase‐positive Staphylococci (7.6%), Prototheca sp. (2.2%) and Streptococcus dysgalactiae (1.6%). Coagulase‐negative Staphylococci and coagulase‐positive Staphylococci were associated mainly to chronic inflammatory response and chronic inflammatory response and repair. Samples from which no micro‐organisms were isolated (n = 56) had no histological changes in 82.6% of the cases. These results were higher (P<0.05) when compared to the samples with micro‐organisms and without histological changes (17.4%).
Occurrence and Characteristics of CS31A Antigen‐Producing Escherichia coli in Calves with Diarrhoea and Septicaemia in Argentina
Authors: Mercado E. C. , Rodríguez S. M. , D'Antuono A. L. , Cipolla A. L. , Elizondo A. M. , Rossetti C. A. , Malena R. , Méndez M. A.
Published: March 2003

CS31A is a K88‐related non‐fimbrial adhesin first described on Escherichia coli strains isolated from diarrhoeic and septicaemic calves. In this report, CS31A antigen was screened by immunological methods and confirmed by PCR among bovine E. coli isolates. In addition, CS31A‐producing strains were characterized with respect to different fimbrial antigens, O‐serogroup and other properties related to virulence. Faecal or tissue specimens of 100 diarrhoeic or septicaemic calves and 27 older cattle with different pathologies from 71 outbreaks or individual cases that occurred in Buenos Aires province, Argentina, were examined. CS31A+ E. coli strains were isolated from 21 (21.0%) calves from 16 outbreaks or individual cases. No CS31A+ E. coli was detected in samples from cattle more than 1 year old. Fimbriae F5, F41, F17a and F17b were not detected among the CS31A‐producing strains. Three (14.3%) of the CS31A+ E. coli strains expressed the F17c fimbria. All of the 21 isolates exhibited at least one property of septicaemic strains (resistance to serum, production of aerobactin or colicins) but none of them demonstrated heat‐stable enterotoxigenic activity. CS31A+ E. coli isolates belonged to 10 serogroups, more commonly O8, O7, O17 and O21. The results obtained here confirm the worldwide distribution of CS31A antigen in bovine E. coli strains. However, CS31A+ or CS31A+/F17c+ E. coli were less frequently isolated than they were in North hemisphere countries.
Oceanographic Characteristics of a Multi‐Specific Fishing Ground of the Central South Brazil Bight
Authors: Borzone Carlos Alberto , Pezzuto Paulo Riccardo , Marone Eduardo
Published: March 2003

In the Central South Brazil Bight, a multispecific demersal trawl fishery is conducted by trawlers licensed for the industrial pink shrimp (Penaeus paulensis and Penaeus brasiliensis) fishery. In addition to the pink shrimp, many by‐catch species have become increasingly valued in the last two decades. In spite of the importance of this multispecific fishery, the oceanographic characteristics of the inner continental shelf, onshore the 100 m isobath, are poorly known. In this paper we present, for the fist time, monthly oceanographic records taken from December 1995 to May 1997 with the R/V ‘Diadorim’ at two of the main fishing grounds of this region. Water temperature data showed the formation of a strong thermocline during summer, from November to April. This thermal gradient, due to the South Atlantic central water (SACW) intrusion that reaches these shallow waters, disappeared with the homogenization of the water column during autumn and winter, from May to September. This cold and low salinity water does not originate from local river discharges, but also represents an advection of sub‐Antartic water mass. After this and during spring, a new thermocline develops, reaching its maximal expression from February to March. A maximal gradient was registered in February 1997, when the temperature dropped from 26°C at 7 m to 16°C at 14 m depth. This result shows that the SACW intrusion is a large‐scale phenomenon that regularly influences the whole inner continental shelf up to 20 m. Demersal fishing grounds located in this area were covered during summer by a cold and nutrient‐rich mass of water that resulted in an unusual maximum of chlorophyll a values near the bottom (30 m). The homogenization of the water column and the presence of another cold water mass during winter resulted in a strong semi‐annual thermal cycle on the bottom. The role of this important oceanographic process in fishery production and dynamics deserves further investigation, but the data presented here show evidence for the importance of this phenomenon.