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121.
The diagnosis of enzootic pneumonia at the herd level should be based on a combination of different methods. Currently, clinical examination is usually considered to be a low value method, particularly compared to the direct detection of Mycoplasma hyopneumoniae in lung lesions by PCR. The present study compared the value of accurate clinical examination (including the quantitation of coughing), PCR on bronchoalveolar lavage fluid, and serological testing of blood samples for the purpose of diagnosing enzootic pneumonia. The coughing index (average % of pigs coughing per minute of observation) was determined in fattening pigs from 59 herds, and ranged from 0% to 6.7% with a median of 2.4%. Five hundred and ninety bronchiolar lavage samples and 1179 serum samples were taken from pigs in those 59 herds and tested for M. hyopneumoniae specific DNA and antibodies, respectively. In herds where ?50% of lavage fluids were PCR positive, the likelihood of a higher coughing index was increased by 76% (OR: 1.76; 95% CI: 1.14-2.72) compared to herds with <50% of positive samples. For antibodies (determined by ELISA) a seroprevalence of ?50% increased the likelihood of a high coughing index by 50% (OR: 1.50; 95% CI: 1.03-2.20). In 78.1% of all herds with a seroprevalence of ?50% against M. hyopneumoniae, the PCR-prevalence and the coughing index were above the median (50% and 2.4%, respectively). It was concluded that in fattening pigs a quantitative assessment of the onset of coughing - typically dry and non-productive - improves the diagnosis of enzootic pneumonia and can occasionally substitute for the detection of M. hyopneumoniae by PCR.  相似文献   
122.
This study evaluated the effects of an anesthetic protocol using intravenous ketamine and midazolam, and intramuscular buprenorphine on hematologic variables in cats. Twelve healthy adult cats had blood collected for a complete blood count before and after the induction of anesthesia. There were significant decreases in red blood cell counts, hemoglobin concentrations and hematocrits after the induction of anesthesia. On average, red blood cell counts and hematocrits decreased by 25%, and hemoglobin concentrations decreased by 24%. Based on hematocrit, 3/12 samples (25%) taken while the cats were anesthetized would have been interpreted as belonging to anemic patients while none of the cats would have been considered anemic before anesthesia. This study suggests that a complete blood count performed on blood taken under anesthesia with this anesthetic protocol should be interpreted cautiously in order to not make a false diagnosis of anemia.  相似文献   
123.

Background

Exposure to xenoestrogens in humans and animals has gained increasing attention due to the effects of these compounds on reproduction. The present study was undertaken to investigate the influence of low-dose dietary phytoestrogen exposure, i.e. a mixture of genistein, daidzein, biochanin A and formononetin, on the establishment of testosterone production during puberty in male goat kids.

Methods

Goat kids at the age of 3 months received either a standard diet or a diet supplemented with phytoestrogens (3 - 4 mg/kg/day) for ~3 months. Plasma testosterone and total and free triiodothyronine (T3) concentrations were determined weekly. Testicular levels of testosterone and cAMP were measured at the end of the experiment. Repeated measurement analysis of variance using the MIXED procedure on the generated averages, according to the Statistical Analysis System program package (Release 6.12, 1996, SAS Institute Inc., Cary, NC, USA) was carried out.

Results

No significant difference in plasma testosterone concentration between the groups was detected during the first 7 weeks. However, at the age of 5 months (i.e. October 1, week 8) phytoestrogen-treated animals showed significantly higher testosterone concentrations than control animals (37.5 nmol/l vs 19.1 nmol/l). This elevation was preceded by a rise in plasma total T3 that occurred on September 17 (week 6). A slightly higher concentration of free T3 was detected in the phytoestrogen group at the same time point, but it was not until October 8 and 15 (week 9 and 10) that a significant difference was found between the groups. At the termination of the experiment, testicular cAMP levels were significantly lower in goats fed a phytoestrogen-supplemented diet. Phytoestrogen-fed animals also had lower plasma and testicular testosterone concentrations, but these differences were not statistically significant.

Conclusion

Our findings suggest that phytoestrogens can stimulate testosterone synthesis during puberty in male goats by increasing the secretion of T3; a hormone known to stimulate Leydig cell steroidogenesis. It is possible that feedback signalling underlies the tendency towards decreased steroid production at the end of the experiment.  相似文献   
124.
Hemorrhagic septicaemia, an acute disease caused by P multocida capsular type B which is rarely detected in Europe, caused considerable losses in fallow deer, cattle and pigs within a region along the border of the federal states Brandenburg and Saxony-Anhalt in the summer of 2010. Clinical appearances and diagnostic findings are presented and possible triggering influences discussed. Pasteurella multocida capsular type B has not been cultivated from clinically healthy cattle and pigs of the region. Examination of fallow deer and roe deer in the region revealed the presence of singular carriers, which may act as a source of clinical infections.  相似文献   
125.
A novel indirect ELISA test using deoxycholate extracted antigens coated onto a hydrophobic polystyrene surface for measurement of serum antibodies specific for Mycoplasma hyosynoviae was developed. Sensitivity and specificity of the test were found to be superior to previous ELISAs as tested on porcine serum following experimental Mycoplasma infections as well as by analysis of samples from one Danish herd known to be free of M. hyosynoviae and samples from two Norwegian herds without clinical suspicion of M. hyosynoviae infections since their establishment. The epidemiology of M. hyosynoviae infection was then investigated in Danish pig herds with evidence of clinical M. hyosynoviae arthritis (MhA herds, n = 4) and in herds with M. hyosynoviae-carriers among slaughter pigs, but with limited clinical lameness (MhC herds, n = 4). M. hyosynoviae bacteriaemia and tonsil-carrier state were determined by culture of cross-sectional samples of whole-blood (n = 238) and tonsil scrapings (n = 322), respectively. Levels of serum antibodies (n = 396) were measured by the novel indirect ELISA test. There was no significant difference in the ELISA results between the MhA and the MhC herds. Pigs that were tonsil-carriers had a significantly higher response in the ELISA test (P < 0.001) than non-carriers. Slaughter pigs showed higher ELISA values (P < 0.001) and they were more prone to be tonsil-carriers (P < 0.001). The most critical period for spread of the infection seems to be the nursery period (4-12 weeks). The results indicate that M. hyosynoviae infection progresses similarly in herds irrespective of the presence of clinical arthritis. Thus, clinical arthritis due to M. hyosynoviae is probably triggered by other host or herd factors than low levels of serum antibodies or by differences in virulence factors between M. hyosynoviae strains.  相似文献   
126.
In the wake of a scrapie monitoring programme 2002 in Mecklenburg-Westpomerania a total of 10 positive cases were identified after culling at a suffolk-farm with about 1000 animals. Scientific based recommendations are difficult to judge as longitudinal studies and subsequent quantitative risk factors regarding the epidemiology of scrapie are either not available or conflicting. Given this background a risk assessment was developed that is based on the probability of validated risk factors considering special husbandry and circumstances at the very farm.  相似文献   
127.
The aim of the present study in cats was to investigate the potential effects of a calcium carbonate and chitosan supplement on blood parameters in aged cats with moderate chronic renal failure and on the mineral balance in adult healthy cats. For the trials, 10 neutered cats 2-4 years of age were fed for 21 days and six neutered cats (2 male and 4 female), 14 years of age, with elevated urea and phosphorus level in the plasma were fed for 35 days with a supplement. The apparent digestibility of phosphorus was (p < 0.05) reduced in the treatment period. Plasma urea inorganic phosphate decreased significantly (p < 0.05) in the old cats after 35 days of treatment. The treatment had a significant effect on the phosphorus, gross energy, dry matter, crude ash, crude fiber and crude protein digestibility in adult healthy cats. The practical implication could be an alternative treatment option for cats refusing to ingest veterinary renal diets.  相似文献   
128.
Genomic diversity among strains of Mycoplasma hyosynoviae isolated in Denmark was assessed by using amplified fragment length polymorphism (AFLP) analysis. Ninety-six strains, obtained from different specimens and geographical locations during 30 years and the type strain of M. hyosynoviae S16(T) were concurrently examined for variance in BglII-MfeI and EcoRI-Csp6I-A AFLP markers. A total of 56 different genomic fingerprints having an overall similarity between 77 and 96% were detected. No correlation between AFLP variability and period of isolation or anatomical site of isolation could be demonstrated. An examination of the clonal appearance of M. hyosynoviae isolates recovered from seven herds affected with arthritis revealed presence of several genotypically distinct variants of the organism in a single herd, indicating that different strains may simultaneously be involved in an outbreak of the disease.  相似文献   
129.
130.
The aim of this study was to determine the prevalence of Campylobacter spp. and Yersinia spp. in a total of 1,040 faecal samples taken from animals at different ages from four farrowing and twelve fattening herds. In the farrowing unit, faeces were collected from 68 sows (faecal samples) and 256 suckling piglets (rectal swab samples). Further samples were collected from 362 growing and 354 finishing pigs (rectal swab samples). Additionally, 56 feed and environmental samples were collected. During the slaughtering process, 122 pigs and their carcasses respectively, were sampled three times. Finally, 86 meat and minced meat samples were taken from 34 retail stores. Campylobacter spp. were isolated in sows (33.8 %), piglets (80.9 %), growing (89.2 %) and finishing (64.7 %) pigs. Yersinia spp. were detected in growing (15.2 %) and finishing (13.3 %) pigs only. After twelve hours of chilling neither Campylobacter spp. nor Yersinia spp. were detected. In raw meat samples, Campylobacter spp. were isolated from one liver sample and Yersinia enterocolitica from two meat samples. Common slaughter techniques and hygiene procedures may be effective tools to reduce the risk of contamination and recontamination of meat products since Campylobacter spp. and Yersinia spp. were found only sporadically in raw meat samples.  相似文献   
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