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1.
Faecal samples from 150 buffalo calves, one to 150 days old, located in various districts of Sri Lanka, were examined for group A rotavirus antigen by a screening enzyme linked immunosorbent assay (ELISA). Positive samples were confirmed by the blocking ELISA. In the calves studied 27·3 per cent were diarrhoeic, and the rest were non-diarrhoeic but were in contact with the animals showing diarrhoea. Antigen was detected in 36·6 per cent of the diarrhoeic animals and in 11·9 per cent of the nondiarrhoeic animals. There was a strong association between the presence of antigen in faeces and diarrhoea in these animals (ξ2 = 46·98; P<0·001). Of the 146 serum samples examined for antirotaviral antibodies, by the blocking ELISA at a single serum dilution (1:20) against a constant dose of antigen (8 units), 68·5 per cent were positive indicating a widespread infection with the virus in the population studied. This is the first record of the detection of rotavirus and its association with diarrhoea in buffalo calves in Sri Lanka.  相似文献   

2.
The amelioration of aflatoxicosis in Japanese quails was examined by the dietary addition of live yeast (Saccharomyces cerevisiae; SCE). Yeast incorporated into the diet at 1 g kg−1was evaluated for its ability to reduce the deleterious effects of 2·5 mg total aflatoxin ( ; 82·30 per cent 1 , 2·06 per cent 2, 7·68 per cent 1and 7·96 per cent 2) kg−1diet on growing Japanese quail chicks from 10 days to 45 days of age. Forty 10-day-old Japanese quail chicks were assigned to 2×2 factorial arrangement of treatments (control, , , plus ) each consisting of 10 quails. The performances of birds were evaluated. The treatment significantly and dramatically decreased food consumption and body-weight gain from the first week onwards. The significant adverse effect of on the food conversion ratio was also determined from week 1 to the end of the experiments. The addition of to the -containing diet significantly reduced these deleterious effects of on food consumption, body-weight gain and food conversion ratio. Compared to controls, the cumulative body weight gain was reduced by 37 per cent among the quails consuming without , but increased 15 per cent for the birds fed plus . Interestingly, the single inclusion of to the -free diet provided significant improvements in all the investigated growth performances of birds (approximately 40 per cent) compared to controls.  相似文献   

3.
Near infrared spectroscopy (NIBS) was used to detect changes in brain oxygenation in five tranquilised calves that were placed on a hypoxic gas mixture (10 per cent O2/90 per cent N2) and hyperoxic gas mixture (30 per cent O2/70 per cent N2) for five minutes at each concentration. A NIRO 500 (Hamamatsu, Japan) was used for the NIBS, with the incident light source and separate detector (optodes) placed on shaved skin on the most dorsal surface of the frontal bone. Sequential arterial blood gas sample analyses provided confirmation of the appropriate change in systemic oxygenation status. By the end of the five-minute-period of breathing 10 per cent oxygen, NIBS of the calf head detected highly significant changes in haemoglobin oxygenation reflective of hypoxaemia, with oxyhaemoglobin decreasing by 23·5 units (P<0·01) and deoxyhaemoglobin increasing by 45·6 units, (P<0·01) from the baseline of breathing room air. Total haemoglobin (oxyhaemoglobin + deoxyhaemoglobin) showed a significant increase of 22·1 units (P<0·05) but there was no significant change in LAIRS determined cytochrome aa3 oxygenation. Concomitant blood gas alterations included significant decreases in Pa)2 (−27·8 mmHg, P<0·01), haemoglobin saturation (−29·0 per cent, P<0·05), and PaCO2 (−7·8 mmHg, P<0·05) and significantly increased blood pH (0·059, P<0·05). At the end of the five minutes of breathing 30 per cent oxygen NIBS of the calf head detected significantly increased oxyhaemoglobin (13·1 units, P<0·01) and decreased deoxyhaemoglobin (−13·7 units, P<0·05) when compared with baseline breathing of room aim. Total haemoglobin and cytochrome aa3 were unchanged from baseline. The accompanying arterial blood gas changes included significant increases in PaO2 (30·9 mmHg, P<0·05), arterial O2 saturation (11·7 per cent, P<0·05), and significantly decreased pH (−0·026, P<0·05), This study showed that NIRS can be used to continuously and non-invasively detect cerebral oxygenation changes in the live calf in response to both increased and decreased systemic arterial oxygen. Additionally, despite induction of profound hypoxaemia, cytochrome aa3 in the brain did not appear to become reduced.  相似文献   

4.
The osmotic fragility of the erythrocytes was measured in blood samples collected from randomly selected healthy and infected dogs at a dogs' rescue shelter. The dogs were classified into six groups on the basis of the final diagnoses from clinical, post mortem and laboratory findings. The minimum (less than 5 per cent) and maximum (more than 90 per cent) haemolysis of the erythrocytes of the clinically normal dogs (group 1), occurred in 0·60 per cent and 0·30 per cent solutions of sodium chloride (NaCI). For the non-anaemic hookworm-infected dogs (group 2a) the respective values were 0·8 per cent and 0·4 per cent NaCl, and for the anaemic hookworm-infected dogs (group 2b) they were 0·85 per cent and 0·5 per cent NaCl, respectively. The erythrocytes from dogs with Babesia canis (group 3), concurrent hookworm and B canis (group 4) and Ehrlichia canis infections (group 5) had minimum haemolysis in 0·75 per cent NaCl and maximum haemolysis at between 0·20 per cent and 0·35 per cent NaCI solutions. The derivative fragiligrams for groups 2a, 2b, 3 and 4 were shifted to the left, whereas the fragiligram for group 5 was similar to that for the clinically normal dogs (group 1). The left shift for the hookworm-infected dogs was due to the increased osmotic fragility of a minor sub-population of the erythrocytes, but for the dogs, infected with B canis major sub-populations of the erythrocytes had an increased osmotic fragility.  相似文献   

5.
Clenbuterol (0·8 μg kg −1 intravenously) was investigated in ponies (small horses) anaesthetised with acepromazine, detomidine and thiopentone, then halothane in oxygen alone (hyperoxic group) or with nitrous oxide (hypoxic group). Following instrumentation, ponies were placed in dorsal recumbency for 60 minutes, clenbuterol (both groups) or a saline control (hyperoxic group) given, and cardiopulmonary parameters monitored for a further 60 minutes. In the hyperoxic group, clenbuterol administration resulted in a transitory (<five minutes) 15 per cent fall in arterial blood pressure and 78 per cent rise in intramuscular blood flow. Heart rate increased from a mean of 42 (SD 4) to 54 (12) beats per minute, the rise being significant for 15 minutes. Cardiac index increased from 2·1 (0·7) to 3·-9 (0·7) litres m−2 and remained significantly elevated for the remainder of the measurement period. Cardiovascular changes in the hypoxic group were similar. 30 minutes after clenbuterol administration, PaO2 had changed non-significantly from 32·.3 (19·2) to 33·.4 (17) kPa in the hyperoxic group and from 7·9 (1·8) to 8·.6 (1·3) kPa in the hypoxic group. The study concludes that under these experimental conditions, clenbuterol does not cause significant improvement in arterial oxygenation, but its cardiovascular effects are minimal or advantageous.  相似文献   

6.
The effect of dietary chloride content (0·2, 0·4 and 1·3 per cent chloride on a dry matter basis) on the disposition of a single oral dose of bromide (14 mg kg−1 was evaluated in normal beagles. Increasing the dietary chloride content from 0·2 to 1·3 per cent resulted in a significant decrease in the mean apparent elimination half-life from 69 ± 22 days to 24 ± 7 days. The mean area under the concentration curve ( ) for dogs fed 1·3 per cent chloride was significantly smaller than the for dogs fed 0·2 per cent chloride. Dietary chloride had no effect on the maximum serum concentrations (Cmax) or on the time (Tmax) to reach the maximum concentrations. The steady-state serum bromide concentrations predicted from the single dose data for daily doses of 14 mg kg−1 of bromide were significantly lower in dogs fed 1·3 per cent chloride (310 ± 150 mg litre−1) than in dogs fed 0·2 per cent chloride (1950 ± 1140 mg litre−1). The predicted mean daily doses of bromide necessary to maintain serum levels within the therapeutic range for dogs fed 1·3 per cent chloride (43 ± 13 mg kg−1) were almost twice as high as the dose estimated for dogs fed 0·4 per cent chloride (22 ± 3 mg kg−1) and nearly three times as high as the dose estimated for dogs fed 0·2 per cent chloride (15 ± 4 mg kg−l). These differences were statistically significant (P=0·002).  相似文献   

7.
In order to establish the prevalence of viral infections of the bovine fetus in Argentina, a serological survey for antibodies against viral agents currently affecting cattle in this country was conducted. Antibodies against foot-and-mouth disease virus (FMDV), bovine herpesvirus-1 (BHV-1), bovine leukaemia virus (BLV), bovine rotavirus (BRV), bovine coronavirus (BCV), bovine viral diarrhoea virus (BVDV) and parainfluenza-3 (PI-3) were investigated in a total of 315 fetal serum samples. Conventional techniques were used: indirect immunofluorescence (FMDV, BHV-1, BVDv and BCV), radial immunodiffusion (BLV), ELISA (BRV) and haemagglutination inhibition (PI-3). Antibodies against BHV-1, BVDV and PI-3 were detected in samples from fetuses in the second and third trimester of gestation, with a prevalence of 1·21 per cent (two of 165), 2·03 per cent (four of 197) and 5·08 per cent (nine of 177), respectively. Either antibodies or non-antibody factors able to bind to BRV and Bcv antigens were detected with a prevalence of 2·44 per cent (five of 205) and 4·54 per cent (five of 110), respectively. In addition, 14·68 per cent of non-specific inhibitors of PI-3 mediated haemagglutination were found. No seropositives against FMDV and BLV were detected.  相似文献   

8.
Cloning of the canine yes oncogene was attempted from a c library derived from a healthy canine spleen using a human c-yes-1 probe. The nucleotide and amino acid sequences revealed that the canine yes gene contained an open reading frame consisting of 539 amino acids. Its product had a molecular mass of 60,368 Daltons and showed 95·9 per cent and 90·4 per cent homology with human and chick p61c-yes, respectively. Moreover, the product had a myristylation signal, src homology region (SH) 3, SH2, and tyrosine kinase domains showing 98·8 per cent and 96·0 per cent homology with those of human beings and chickens, respectively. These findings indicate that the products of the canine yes gene may have non-receptor-type tyrosine kinase activity on the cell membrane, as is the case in human and chick p61c-yes  相似文献   

9.
The electroencephalogram (EEG) has been used in human clinical anaesthesia as an indicator of cortical activity and as an indicator of the depth of anaesthesia. It would be useful if it provided a reliable indication of the depth of anaesthesia of horses. In this study anaesthesia was induced with thiopentone and maintained with halothane in nine ponies. The end tidal halothane concentration (PE-Hal) was monitored and 20 seconds of EEG were recorded at 0·8 per cent, 1·0 per cent and 1·2 per cent halothane, equivalent to the minimum alveolar concentration (mac), 1·25 mac and 1.5 mac. Each 20 second block of data was divided into one second segments and averaged to give one second of averaged EEG from which a frequency spectrum was obtained by using a fast Fourier transformation. The power of the waveform at low frequency (1 to 3 Hz) was compared with that at higher frequency (9 to 11 Hz). The median frequency and 95th percentile (spectral edge) were also calculated. The spectral edge frequency had the best correlation with PE-Hal  相似文献   

10.
The effects of a single challenge with 60,000 infective Ostertagia ostertagi larvae on blood and gastrointestinal mucosal gastrin concentrations, gastrin-producing G-cell numbers in the pyloric mucosa and growth of different parts of the gut were investigated in 16, two-and-a-half-month-old calves. Infected calves exhibited a rise in abomasal pH which was accompanied by a 145 per cent increase in wet weight of the fundic mucosa (P<0·05) and a significant rise in blood total gastrin concentrations (P<0·01). Circulating little gastrin (G-17) was unaffected. Pyloric mucosal total gastrin concentrations remained unaltered in the infected calves until day 28 when levels fell to 36·9 per cent of control group values (P<0·01). Pyloric mucosal G-cell numbers declined during the experiment in the infected group. It is suggested that release of previously stored tissue gastrin and not a change in Gcell numbers contributes to the hypergastrinaemia associated with ostertagia infection in the calf.  相似文献   

11.
Mammary secretions contain leucocytes which may be of value to the neonate. The cells obtained from sow colostrum (1 to 2·5 × 106 ml−1) are mainly lymphocytes (10 to 25 per cent) and epithelial cells (more than 20 per cent). In milk, there are few lymphocytes (0·5 to 2 per cent) and mostly alveolar epithelial cells. The study of lymphocytes in the mammary secretions of sows has been made difficult by the high proportion of epithelial cells, which could not be separated from lymphocytes, and by a high background in membrane immunofluorescence labelling. This paper describes a method for the study of the cells in the mammary secretions of sows by flow cytometry. It showed that 70 to 90 per cent of colostral lymphocytes were T lymphocytes, with T8 lymphocytes predominating over T4, and that the ratio T4/T8 was significantly lower in colostrum (0·57) than in blood (0·80). There were no lymphocytes expressing interleukin-2-receptors in the colostrum of sows.  相似文献   

12.
A modified indirect immunofluorescence method, using rat liver as substrate, was developed to determine the immunoglobulin isotypes forming antinuclear antibodies in sera from 12 antinuclear antibody-positive dogs out of 121 dogs with natural Leishmania infection. Immunoglobulin M was found to be the most frequent component of antinuclear antibodies (91·7 per cent), followed by IgG (41·7 per cent) and IgA (33·2 per cent). When these immunoglobulin isotypes were titrated, IgG antinuclear antibodies showed higher titres (1:200) than IgM and IgA antinuclear antibodies (1:50 and 1:20 respectively). Most of the antinuclear antibody-positive dogs simultaneously had two immunoglobulin isotypes, whereas none had all three immunoglobulin isotypes at the same time. Spearman rank correlation analysis showed no significant correlation between antinuclear antibody titres and circulating immune complexes or immunoglobulin levels. The low incidence of antinuclear antibodies and the absence of a clear relationship between isotype titres and clinical signs suggest a minor pathogenic role of antinuclear antibodies in canine leishmaniasis.  相似文献   

13.
A survey of the prevalence and type of renal disease was carried out at a Dublin abattoir in 1979-80. Of 4166 cattle surveyed, 173 (4.2 per cent) had kidneys rejected for gross abnormalities. The rejection rate was 7.7, 1.7, 2.2 and 28 per cent for cows, bullocks, heifers and bulls, respectively. The most common reason for rejection was focal interstitial nephritis (60.1 per cent of rejected kidneys). Other lesions included cysts (26.0 per cent), pigmentation (6.4 per cent), pyelonephritis (3.5 per cent), amyloidosis (2.9 per cent), glomerulonephritis (0.6 per cent), renal atrophy (0.6 per cent) and agonal haemorrhage.  相似文献   

14.
The nucleotide (nt) sequence of the C encoding the retinal rod cyclic 3′5′- phosphodiesterase (PDE) α and γ subunits from two strains of dogs - (i) Labrador Retrievers homozygous for autosomally recessively inherited rod-cone degeneration and (ii) the wild-type Beagle - are reported. Cloning of these subunits was accomplished by polymerase chain reaction using retinal CDNA libraries as templates. The nt sequence of α predicts a 861-amino-acid polypeptide which is 97·7 per cent and 96·9 per cent identical to the bovine and human counterparts, respectively. γ encodes an 87-amino-acid polypeptide differing from bovine and murine gamma subunits by only one amino acid. Since no differences were found between these two strains of dogs, the cause of the Labrador Retriever's degeneration remains to be determined.  相似文献   

15.
Fifty-five swab-wash specimens from dogs were cultured at 32°C on Sabouraud's dextrose agar either with or without 1 per cent Tween 80, Ushijima's medium A and modified Dixon's and Leeming's media. The counts of Malassezia pachydermatis were not significantly different after three or seven days of incubation. Colony counts on contact plates were significantly greater after incubation for seven days on Sabouraud's dextrose (P<0·001) and modified Dixon's agars (P<0·05) than after three days at 26°C, but not at 32°C. Counts on Sabouraud's or modified Dixon's agars after incubation at 32°C and 37°C were not significantly different. When compared with aerobic culture, an atmosphere containing 5 to 10 per cent carbon dioxide significantly (P<0·01) increased the frequency of isolation and colony counts on Sabouraud's dextrose agar but not on modified Dixon's agar.  相似文献   

16.
The rates of evaporation of moisture from the skin in the lumbodorsal, perineal and scrotal regions of cattle were measured in thermoneutral and high environmental temperatures. The rates of evaporation from the perineal and scrotal regions of heifers and bulls were significantly (P<0–001) greater than those from the lumbodorsal areas. The lumbodorsal rate of evaporation increased significantly (P<0·001) when cows and bulls were transferred from a thermoneutral to a hot environment and the rate of evaporation from the scrotum of bulls showed a similar increase; the rate of evaporation from the perineum of cows increased to a smaller extent (P<0·05) under the same conditions. The rate of evaporation from the perineum of cows reached a maximum on the day of oestrus but the stage of the oestrous cycle had no effect on the lumbodorsal rate of evaporation.  相似文献   

17.
Premature spiral deviation of the penis was investigated in 1083 British breed beef bulls in 42 herds in Victoria (35) and Western Australia (7) by means of the serving capacity test. The herd prevalence was 60%. The prevalence of the defect at the initial test for all bulls was 10%. The prevalence in 635 polled bulls was 16% compared to a prevalence of 1 % in 448 horned bulls. The breed prevalence and the number of bulls tested per breed was Red Poll 27% (15), Murray Grey 25% (4), Poll Shorthorn 21 % (34), Angus 17% (415), Poll Hereford 10% (167) and Hereford 1 % (448). The difference between the last 2 breed types was highly significant (P<0.001). The prevalence of the defect increased from 0 to 30% over 9 years in one Victorian herd. The age of affected bulls varied from 2 to 11 years with most affected bulls aged from 3 to 6 years. Common ancestry was found between affected bulls in Western Australia, providing circumstantial evidence that it may be an inherited defect. None of the 103 affected bulls examined in this study had suffered obvious injury to the penis or prepuce. Eighty per cent of 56 affected bulls from Victoria had low serving capacity. Four bulls (2 from each state) with moderate to severe spiral deviation of the penis attained pregnancy rates of 43%, 33%, 3% and 3% respectively, in single sire mating trials. Recommendations for culling defective bulls are presented, based on the herd prevalence and severity of the defect in individual bulls.
It is concluded that bulls with moderate to severe spiral deviation of the penis have reduced fertility and remain permanently affected. The serving capacity test is a valuable diagnostic test for this serving defect in unhandled beef bulls. It is a common, although frequently undiagnosed disorder of polled beef breed bulls in Australia.  相似文献   

18.
Quantitative measurements were made on cross-sectional preparations of the distal part of the recurrent laryngeal nerve (RLN) from nine young mixed-breed horses to establish reference values for the total number of myelinated fibres, mean fibre diameter and percentage of thickest fibres (over 9·5 gm) and to delineate diameter distribution curves. The total number of myelinated fibres, mean fibre diameter and percentage of thickest fibres for the left RLN were significantly lower than those of the right RLN (P<0–005). The distribution of fibres was unimodal. The fibre diameter ranged from 1 μm to 17 μm. Approximately, 95 per cent of fibres had a diameter larger than 5 μm.  相似文献   

19.
Serological analysis of blood samples submitted to the Animal Health Trust showed that during 1995, 185 of 9203 unvaccinated horses (2.0 per cent) tested positive for antibodies to equine arteritis virus (EAV), and that during 1996, 46 of 8851 unvaccinated horses (0.52 per cent) tested positive. During both years thoroughbreds were the predominant breed tested and only a small proportion of these (<0.3 per cent), consisting predominantly of imported mares, were seropositive. In contrast, among standardbred horses, from which samples were actively solicited in 1995, 84 of 454 (18.5 per cent) were seropositive. Among standardbreds there was a difference in prevalence between types of horses, with 3.7 per cent of racing horses, 25 per cent of non-racing horses and 41 per cent of stallions testing seropositive. Investigations of seropositive stallions identified during 1994 and 1995 demonstrated that clinically inapparent equine viral arteritis (EVA) had occurred previously in the UK. Of 50 seropositive stallions, nearly half were standardbreds and nearly all had been imported from either North America or the European Union. Whether 34 seropositive stallions were shedding virus in their semen was established either by test mating, by the serology of the covered mares, or by investigation by MAFF following the introduction of the Equine Viral Arteritis Order 1995. Nine of the stallions (26.5 per cent) were identified as presumptive shedders of EAV in semen and among specific breeds, viral shedding was identified in six of 15 (40 per cent) standardbreds and three of nine (33 per cent) warmbloods. In contrast with the outbreak of EVA in the UK in 1993, no signs of disease typical of EAV infection were reported during these investigations, even in mares test mated to stallions shedding the virus.  相似文献   

20.
Bovine serum amyloid-A (b-SAA) was purified from a pool of acute phase serum using hydrophobic interaction chromatography and gel filtration. Serum was applied at a low salt concentration to a phenyl-sepharose column and SAA was eluted with a gradient of 0 to 6 M guanidine-HCI. Fractions containing SAA were pooled, concentrated and further purified by gel filtration on Superose-12. The concentration of SAA in bovine serum was quantified by an indirect ELISA using rabbit anti-human SAA and horseradish peroxidase conjugated donkey anti-rabbit IgG. Dilutions of an acute phase bovine serum sample were used as working standards. The SAA concentration of this standard was determined by comparison with purified b-SAA on SDS-polyacrylamide gel electrophoresis followed by densitometry at 590 nm. The assay detection limit was 3 μg ml−1; the intra-assay coefficient of variation was 4 per cent and interassay coefficients of variation were 5·5 per cent and 7·2 per cent at 66 and 178 μg ml−1 SAA, respectively. In calves experimentally infected with Pasteurella haemolytica type A1 the ELISA was able to detect a 10-fold increase of SAA within 24 hours of inoculation.  相似文献   

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