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1.
On 8 female young cattle from a suckler herd blood sampling (V. jugularis) and body temperature measurements (RT) before (U1; U11) and after transport (U2; U21) and on the next day (U3; U31) were combined with long term heart rate (HF) recording before (U1 to U3) and 23 d later (16 till 18 days) after permanent separation of the young cattle from their dams (U11 to U31). After weaning plasma concentrations of urea and Ca were greater and that of creatinine was smaller in young cattle than before. Characteristic heart rate values before transport and those of the 24-h-recordings were significantly smaller after weaning. Plasma cortisol concentrations before transport were increased (U1: 40.3 +/- 10.4; U11: 16.8 +/- 3.9 nmol/l) and they were only less further elevated after transport (U2: 52.6 +/- 19.5; U21: 33.4 +/- 18.3 nmol/l). On the next day cortisol values (U3: 33.3 +/- 23.7; U31: 12.5 +/- 5.8 nmol/l) were significantly smaller than the initial values. HF increased significantly with loading and with the start of transport comparing the characteristic heart rate values of the other periods of the transport process and the initial values before the transport and of the 24-h-recording after the transport process. Significant mean differences before and after transport could be found for body temperature, creatinine, urea, hematocrit, pO2, Ca, Mg, and Fe. Separation of young cattle from their dams had effects on some variables before transport but did not change the reaction of the animals to transport. Results show the significance of the events and their effects on the animals before transport and their timely relationship for the reactions of the animals during and after transport and the markedly interindividual variation of the reactivity of the young cattle.  相似文献   

2.
Serum and urine were taken from healthy dairy cattle from 22 different farms. 214 animals belonged to the Swiss Brown breed and 210 were crossbreds of Simmental-Red Holstein. The animals were given at least 70 g of sodium chloride with their daily feed ration. On 6 farms sodium chloride was offered ad libitum in form of licks, which was presumed to be sufficient for covering their needs. Concentrations of sodium (UR Na), potassium (UR K) and creatinine were analyzed from serum and urine and fractional excretion of Na and K was calculated. Concentrations of sodium and potassium in urine from all cows (mean +/- sd) was 60.9 +/- 44.7 mmol/l and 370.7 +/- 66.9 mmol/l respectively. The FE values were 0.954 +/- 0.939% for sodium and 173.1 +/- 54% for potassium. In 5.5% of the animals values for UR Na < 10 mmol/l were found. There were no significant differences, however, were found in sodium and potassium excretion among farms. Urine samples of at least 10 animals should be analyzed in order to have a reliable estimation of the supply with sodium chloride within a herd. Our results do not support the hypothesis that low sodium excretion would be a predisposing factor for Bovine Dilative Cardiomyopathy in Simmental-Red Holstein cattle.  相似文献   

3.
Bluetongue virus (BTV) serotype 17 was isolated from cattle with clinical signs of bluetongue disease during 1978 and 1979 epizootics. Bovine sera from 6 herds located in an epizootic region were examined in 1979 for antibodies, using an immunodiffusion (ID) test. Of 300 sera, 164 (54.7%) were seropositive. Sera from statewide surveys of Louisiana cattle in July to August 1980 and December 1980 to January 1981 were tested for BTV antibodies, using the ID test. Fifty-eight of 70 herds (82.9%) and 164 of 597 (27.5%) individual cattle tested in July to August 1980 were seropositive. Fifty-four of 63 (85.7%) herds and 170 of 600 (28.3%) individual cattle tested in December 1980 to January 1981 were seropositive. Significant differences (P less than 0.01) were found in the seropositive rates between the various geographic regions of the state during each survey. Adult breeding-age cattle in 3 sentinel herds were tested for BTV antibodies beginning in 1976 and continuing through January 1981. During this interval, the seropositive rate in 2 of 3 herds was increased. Also, individual cattle in all 3 of these herds converted from seronegative to seropositive, indicating exposure during a particular interval for each herd. The age distribution of seropositive cattle in a dairy indicated that 2-year-old cattle had a seropositive rate comparable with that of older animals in the herd, suggesting that the 2-year-old animals had been exposed to a BTV before they entered the breeding herd.  相似文献   

4.
The collection of test sera for measuring ELISA results was composed of bovine sera with MAT titres of greater than or equal to 1:200 in the leptospirosis MAT and of greater than or equal to 1:5 in the CFT together with sera from a serologically negative and clinically non-suspicious cattle herd. To establish cut-off ODs, the geometric mean net-extinction of the negative serum collection plus 1, 2, and 3 standard deviations were calculated. By comparison of 3 different conjugates from rabbits, it was demonstrated that results from anti-total bovine Ig were superior to anti-IgG and anti-IgM conjugates. Considerations regarding sensitivity and specificity led to the recommendation to use a test serum dilution of 1:160, to apply anti-total bovine Ig conjugates, and to establish the cut-off OD at the geometric mean net-extinction of negative sera plus 3 standard deviations. Under such conditions, agreement between leptospirosis MAT/CFT positivity on the one side and ELISA positivity on the other was reached in 74%. This recommendation is made for cross-sectional studies but not for examinations of clinically suspicious cattle herds.  相似文献   

5.
The aim of the present study was to determine whether a commercially available ELISA could be used to examine bovine milk for antibodies against Neospora caninum. In an initial titration experiment, a milk dilution of 1:2 was found optimal to obtain milk results that were linearly correlated to those obtained with corresponding sera. This dilution was then used to examine 791 milk samples from N. caninum infected herds in the commercial ELISA. Milk results of individual animals were compared with those obtained by the same ELISA for the corresponding serum samples. The linear correlation between milk and serum antibody results of individual animals was characterized by R2 = 0.702. Multiple linear regression indicated that the later the stage of lactation at which an animal was sampled, the higher the milk ELISA result was as compared to the serum ELISA result. The examination of the two-graph receiver operating characteristics revealed an optimal cut-off of 0.261 to obtain similar results in the examination of milk and serum. With this cut-off, the test had a sensitivity and specificity relative to the serum results of 90%. The milk-based commercial ELISA classified more aborting dams as positive than the serum-based ELISA with this cut-off. The milk ELISA may be a valuable tool to assess the herd status with regard to abortion caused by N. caninum.  相似文献   

6.
Paratuberculosis has received increasing attention in France because of the important losses this disease may provoke. The use of certification schemes has proven its effectiveness for the protection of healthy herds against diseases transmitted mainly by trade. The economic justification of such schemes in the particular case of paratuberculosis is studied, for French cattle herds, using a cost/benefit approach. The basic economical hypotheses and estimates have been proposed and carefully examined by a working group composed of paratuberculosis experts and field specialists. By adopting the point of view of a breeder that buys animals, we first estimated the benefits resulting from the non-introduction of the disease. They were then compared with the costs resulting from the fact that the vendor reports its own certification costs on the price of the animals he sells. Two average herds (the mean French beef herd and the mean French dairy herd), and two certification levels were studied. The results show that, currently, the use of the certification is not very economically profitable in French cattle herds. This conclusion, however should be reappraised if the certification costs decrease, for example with the commercialization of diagnostic tests on mixtures.  相似文献   

7.
Antibodies against Fasciola hepatica were detected in serum and individual milk samples of dairy cattle using an ELISA. Percentage positivity (PP) values in milk samples were related to serum PP values and were not influenced by days into lactation. The correlation coefficient between serum and individual milk samples was highly significant (r=0.84, P<0.005). The correlation coefficient between herd seroprevalence and herd milk antibody prevalence was 0.96. The correlation coefficient between prevalence measured by faecal egg count and both seroprevalence and milk antibody prevalence within the herd was 0.87. The diagnostic sensitivity and specificity for milk were 92% (95% CI=89-96) and 88% (95% CI=85-91), respectively, when the serum test was considered as a gold standard. In conclusion, the level of antibody to F. hepatica in milk is significantly correlated with the antibody level in serum and this ELISA is suitable as a means of routine veterinary diagnosis of exposure to F. hepatica in cattle and an alternative to testing sera.  相似文献   

8.
Serological examinations for Gorynebacterium pseudotuberculosis in-fection were carried out in 14 known positive herds and in 1 herd that had beeni recently established through purchase of animals from different herds. Serum samples were collected sequentially on up to 4 occasions from animals during their first year of life. In most herds, these animals were examined clinically for superficial swellings once or twice during the same period.The adult goats in 8 infected herds were examined both clinically and serologically. Age distribution was similar in each of these herds. All serum samples were examined for antibodies against Gorynebac-terium pseudotuberculosis in both the bacterial agglutination test (BAT) and the hemolysis inhibition test (HIT).The proportion of kids which were seropositive in both tests de-creased to zero at 4 months of age. At the age of 11–12 months, the proportion of seropositive animals was about 50 % in the BAT and 30 % in the HIT.When examined when housed for the winter at the age of about 8 months (mean age), the prevalence of animals with superficial swellings was 7 %. At the age of about 1 year (mean age), 29 % of the examined animals had such lesions. In the recently established herd, only a few of the yearlings were seropositive.Titre values in BAT and HIT increased until 6 years of age. Anti-body titre values were significantly lower in yearlings than in older goats in both tests, P < 0.005. No significant difference in the propor-tion of goats with superficial swellings was seen at the different ages.  相似文献   

9.
A comparative serological study was conducted using the Leptospira microscopic agglutination test (MAT). Genotypes hardjoprajitno (HP), hardjo-bovis A (HA), and hardjo-bovis B (HB) were compared to determine which best detects hardjo antibody in cattle serum. A total of 2,431 cattle sera were tested. Sera were collected from 4 geographic regions of the United States. Samples were obtained without knowledge of breed, age, vaccination history, or herd health status. Of the sera collected, 60.7% (1,475) were negative at the 1 : 100 dilution for all three genotypes. Serological reactivity at the 1 : 100 dilution was identified in 956 (39.3%) of the sera tested. Considering the 956 positive sera, 941 (98.4%) reacted to HP, whereas the remaining 15 sera (1.6%) reacted to only HA and/or HB. A total of 394/941 (41.9%) HP positive sera failed to react to HA or HB. The results of this study support the conclusion that HP antigen was most sensitive in detection of hardjo antibody.  相似文献   

10.
We established an enzyme-linked immunosorbent assay (ELISA) system for the quantitation of bovine macrophage colony-stimulating factor (M-CSF) and used it to measure the serum M-CSF levels in bovine fetuses and calves. The average serum M-CSF level was 2.7+/-1.5 ng/ml in 39 calves under 100 days old, and 1.8+/-0.8 ng/ml in 15 cattle between 101 and 418 days old. Fetal sera samples (n = 6) prepared from cattle between 150 and 280 days of gestational age had a higher average level of M-CSF (8.8+/-1.4 ng/ml). Alteration in serum M-CSF levels in each individual calf was also measured. The serum levels of M-CSF in calves at 0-1 day after birth ranged from 0.52 to 7.3 ng/ml. During the period 113-125 days after birth, serum levels were around 1.4+/-0.39 ng/ml. Although serum M-CSF levels generally decreased as the age of calves advanced, differences among individuals, especially among newborn calves, were observed.  相似文献   

11.
A serological survey was carried out in order to determine the prevalence of antirotavirus antibodies in Moroccan cattle under different management conditions. From the 493 serum samples examined, 325 (65.9%) were found positive, using a counter-immunoelectroosmophoresis technique. Animals of indigenous breed coming from farms with rapid turnover or large number of animals, or having frequent contacts with imported cattle, had a higher rate of seropositivity; however, positive sera were also found in cattle from small farms in remote areas, showing that rotavirus infection is ubiquitous in that country. No relationship was found between the prevalence of anti-rotavirus antibodies and the frequence of calf diarrhoea. The percentage of seropositive animals in a herd has to be considered as an epidemiological indicator.  相似文献   

12.
A commercial ELISA detecting antibodies against bovine viral diarrhoea Virus (BVDV) was analysed for its applicability for bulk-milk screening. Detection limits were analysed using native and concentrated milk samples (milk treated with rennet and ammonium sulfate precipitated) from 10 cows whose sera showed different reactivity levels in the ELISA and from two cows which gave birth to persistently infected calves during the last year. Further this and a second commercial ELISA were used to screen 591 randomly selected bulk-milk samples. To clarify discrepancies thirty-nine herds were included in a follow-up study. A second bulk-milk sample and serum samples from 10 young cattle of 6 to 28 month of age per herd were analysed for antibodies against BVDV. The results of this second testing and the detection of viremic animals in 4 herds confirmed the results from initial bulk-milk testing with both tests. The analysed test is suitable for bulk-milk testing although its application is limited by vaccination.  相似文献   

13.
The present study analyzed Ostertagia ostertagi antibodies by indirect ELISA in milk samples in two cattle systems in Mediterranean Spain to indirectly monitor gastrointestinal nematode (GI) parasitism effects on production. Individual samples from 10 animals and the corresponding milk herd samples were collected from 133 herds in Girona (intensive management) and 123 herds in Minorca (extensive management). Both locations showed high and significant positive relationships between average optical density ratios (ODR) of individual animals and ODR in their milk tank. Although antibodies levels were low, there were significantly higher in Minorca. Negative correlations between ODR values and milk production were found in both systems. Importantly, in Minorca, average herd milk production was higher in the herds that treated their animals against GI nematodes compared to those that did not treat. The ELISA technique was valuable to indirectly assess differences in the level of GI nematode infection even in cattle production systems with low levels of infection.  相似文献   

14.
A total of 1276 cattle from 76 farms in 8 villages were examined by palpation of the skin for evidence of hypodermosis. The effects of age, sex, breed, and colour of cattle on hypodermosis were investigated. The overall prevalence was 31.9%. The mean number of warble fly larvae on infested animals was 8.46. Hypodermosis infestations were encountered in all the villages visited. Within a herd, the intensity of infestion decreased with the age of cattle. Infestation rates of warble fly larvae were lower in native cattle, in females, and in piebald animals.  相似文献   

15.
The present study analyzed Ostertagia ostertagi antibodies by indirect ELISA in milk samples in two cattle systems in Mediterranean Spain to indirectly monitor gastrointestinal nematode (GI) parasitism effects on production. Individual samples from 10 animals and the corresponding milk herd samples were collected from 133 herds in Girona (intensive management) and 123 herds in Minorca (extensive management). Both locations showed high and significant positive relationships between average optical density ratios (ODR) of individual animals and ODR in their milk tank. Although antibodies levels were low, there were significantly higher in Minorca. Negative correlations between ODR values and milk production were found in both systems. Importantly, in Minorca, average herd milk production was higher in the herds that treated their animals against GI nematodes compared to those that did not treat. The ELISA technique was valuable to indirectly assess differences in the level of GI nematode infection even in cattle production systems with low levels of infection.  相似文献   

16.
The association between ocular squamous cell tumors and various measures of solar radiation was evaluated for 2,775 contemporaneous Hereford cattle. The animals were from 34 herds located in 21 states in the United States and in one Canadian province. Examinations and photographs were made of the eyes of all cows and heifers in a herd; 33 herds were examined between June and August 1957 and 1 herd was examined in 1958. Solar radiation was measured by altitude and mean annual hours of sunshine applying to an individual herd, and global radiation, a cloudiness index, and elevation of nearby National Weather Service stations. All measures of solar radiation provided evidence of a significant association between increasing risks of developing cancer eye and increasing levels of radiation; adjustments were made for possible confounding effects of age and corneoscleral pigmentation. Associations were evident whether affliction was defined as the occurrence of any type of tumor (ie, plaque, papilloma, or carcinoma), or as the occurrence of only papilloma or carcinoma. Average ages of affected cattle also tended to be lower at high radiation levels than at low levels, further supporting the hypothesis that solar radiation has an important role in the development of this disease. In view of the heritability of eye pigmentation and its inhibitory effect on lesions, cancer eye may be controlled by selective breeding for increased pigmentation in and around the eye to afford protection against the harmful effects of incident UV radiation.  相似文献   

17.
A serologic survey study of 5,076 Austrian cattle farming herds was carried out in the period of December 1988 till March 1990. One animal was randomly selected from each herd and the antibody titer against Anaplasma marginale in blood serum samples was evaluated by means of the complement fixation test. The number of these tested blood samples was 3.6% of 140,081 cattle herd farms of Austria. 109 (2.1%) of the tested animals showed positive titers (1:10) against Anaplasma marginale, in relation to the 140,081 cattle herds 0.08%, 4,786 (94.3%) blood serum samples were sero-negative, 188 (3.8%) reacted anticomplementary. The highest number of antibody-positive animals of 8 tested Austrian districts could be found in Carinthia (46 = 5.7%). In Burgenland all tested sera turned out to be negative. Concerning the distribution of sero-positive animals in Austria it can be stated that a decrease of positive reactors from southern to northern region is evident. A connection between the occurrence of anaplasmosis in Italy, Yugoslavia, Switzerland and Hungary, is postulated as a result of the different systems of keeping cattle in the provinces and the regional increase of tick invasion. Possibly an intensive animal transportation is of importance due to the introduction of the disease mentioned before. The results obtained show that anaplasmosis does occur in different areas of Austria. For control of this disease in Austria it is proposed that all imported cattle should be tested serologically for antibodies against Anaplasma marginale. Other diseases in connection with anemia should be excluded by clinical, serological, blood-, as well as pathological examinations.  相似文献   

18.
During the grazing period 2002 319 cattle from 31 farms located in 6 districts of southern Bavaria were examined for the presence of ticks in 4- to 5-week intervals, and 287 serum samples were tested for the presence of antibodies against Borrelia burgdorferi and Babesia divergens. Ticks were detected in all 31 farms with a mean prevalence of 69%. 3218 out of 3453 collected ticks were Ixodes ricinus; 139 nymphs, 19 larvae and 77 damaged adult specimens could only be determined to the Genus level (Ixodes).The seasonal pattern revealed the highest frequencies of ticks in May/June and September.The intensity of tick infestation of positive animals was generally low. 76.5% of parasitized cattle had 1-6 ticks per day of investigation. Individual cattle showed up to 250 ticks per day. The percentage of infested animals in each herd varied within the period between 0-100%. The examination of serum samples by immunofluorescence technique (IFAT) revealed positive anti-Borrelia antibody titers (> or = 1:64) for 45.6% of the animals. The within-farm seroprevalence of borreliosis ranged from 20 to 100% in 27 of the 31 farms. A significant correlation could be detected between the number of ticks/cattle and the anti-Borrelia burgdorferi IgG-titer. By contrast, there was no significant correlation between the age of the animals and anti-Borrelia serum titers. For comparative reasons, 64 IFAT-positive serum samples were tested by Western blot techniques for the presence of antibodies cross-reacting with Borrelia garinii antigen. These analyses revealed that 69% of the samples reacted positively, 28% were unclear and 3% were negative. Examinations of the 287 serum samples for the presence of anti-Babesia divergens antibodies revealed one positive animal with a titer of 1:16.  相似文献   

19.
A longitudinal study was performed in a Swedish dairy herd where Neospora caninum had been isolated from a stillborn calf. Starting in autumn 1994, blood samples from all female animals in the herd were collected once yearly until 1999. The sera were analysed for presence of IgG1 antibodies to N. caninum by the iscom ELISA, and by an avidity ELISA to establish the timing of infection. In addition, data on reproductive performance were compiled. During the study the percentage of seropositive female animals increased from 63% to 87%. In 1994 a large number of young animals tested seropositive although their dams were seronegative, indicating that a transmission of the parasite other than the vertical had recently occurred. Low avidity values supported this assumption. The annual abortion rate increased from a mean of 2% before the initiation of the study to 9% in 1994-1998. During the same time, as judged by the avidity data, a large proportion of the animals shifted from being recently to being chronically infected. The source of the external infection in the herd could not be identified.  相似文献   

20.
Previous studies have demonstrated an immunomodulatory role for cimetidine on antibody production. In these experiments we measured IgG subclasses and IgM in rats and also examined the effects of cimetidine on serum levels. Four week-old Sprague-Dawley rats were given cimetidine in three different treatment regimens. IgG subclasses and IgM determinations were carried out by radial immunodiffusion method on sera when animals were 6 and 8 weeks old. IgG1 levels in 6 week-old animals who received intraperitoneal cimetidine on days 1, 2, 3, 4, 5, 6, 8, 9, 15 and 16 were significantly higher (305 +/- 12 mg/l vs 236 +/- 53 in control animals). By 8 weeks of age in control animals, IgG1 levels had fallen to 78 mg/l and were statistically lower than the levels in all cimetidine treatment groups. Eight week-old control animals also demonstrated a four-fold fall in IgG2b levels (613 +/- 310 mg/l) when compared to in 6 week-old control (2295 +/- 1057 mg/l) animals, or 8 week-old animals who had received cimetidine. Animals receiving intravenous cimetidine on days 4, 11 and 18 had significantly lower (133 +/- 3 mg/l) serum levels of IgG2c, at 6 weeks of age, as compared to control animals (177 +/- 16); however, no statistically significant differences in IgG2c levels were observed in 8 week-old animals. No statistically significant differences in the levels of IgG2a or IgM were observed in either 6 or 8 week-old control and experimental animals. It appears that cimetidine does influence certain IgG subclasses, however, route and timing of cimetidine administration are critical in modulating these effects.  相似文献   

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