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21.
Five-month-old male rates were exposed to 0.5 ppm ozone for 50 days, 5 hours a day. A week before the completion of ozone exposure, a biological test was performed to determine the fertilization rate and the survival rate of newborns in both ozone-exposed and control animals. After 50 days, the rats were sacrificed with an overdose of halotane, and testes were collected to assess the morphology and motility of spermatozoa. Neither the morphology of spermatozoa nor motility parameters determined by the CASA (computer-assisted sperm analysis) system showed statistically significant differences between ozone-exposed and control males. The number of successful matings and the survival rate of newborns per litter within one year postpartum were also similar in both groups. However, sperm concentration was by 17% lower in ozone-exposed rats, compared with the control animals.  相似文献   
22.
The aim was to detect and characterize chlamydial infections in guinea-pigs (GP) with ocular disease, study their pathogenicity and zoonotic potential and to test for the presence of Acanthamoebae spp. in GP eyes and to investigate whether they could act as vectors for Chlamydia-like organisms. Overall 126 GP, of which 77 were symptomatic, were screened by clinical examination, cytology, gross pathology, histology, immunohistochemistry, polymerase chain reaction (PCR) and bacteriology. A new Chlamydiaceae-specific intergenic spacer rRNA gene PCR, designed to amplify this segment linking the 16S and 23S regions, was performed. DNA samples were also received from one owner including samples of his cat and rabbit. Guinea-pigs: 48 of 75 symptomatic, but only 11 of 48 asymptomatic GP were positive by PCR for Chlamydophila caviae guinea-pig inclusion conjunctivitis (GPIC) (P < 0.0001). Eighteen of 75 or 15/48, respectively, were positive for DNA from Chlamydia-like organisms. Acanthamoebae-DNA could be found in two GP, of which one was symptomatic. Owner, cat and rabbit: Samples of all three species were positive by PCR for C. caviae GPIC and the owner's one-day disposable contact lenses showed a positive PCR result for the Chlamydia-like organism Parachlamydia acanthamoebae. No Acanthamoebae-DNA could be detected. This study is the first to describe Chlamydia-like organisms in GP and to detect C. caviae GPIC in human, cat and rabbit. Therefore, C. caviae GPIC could pose a zoonotic potential. We believe that the finding of C. caviae GPIC in species other than GP is probably not unique.  相似文献   
23.
1.?Severe foot and hock dermatitis in broiler chickens can reduce growth rate and increase susceptibility to bacterial infection, affecting both profitability and welfare. However, little is known about the underlying physiological changes associated with foot and hock lesions.

2.?This study compared global hepatic gene expression in control birds and those with ammonia-induced foot and hock lesions using Agilent 44?K chicken oligonucleotide microarrays (8 birds per group).

3.?In total, 417 genes were differentially expressed of which 174 could be mapped onto the genome. Genes associated with energy metabolism, thyroid hormone activity and cellular control were affected, while there was also evidence of an up-regulation of genes linked to a pro-inflammatory response.

4.?It is conceivable that pain is the underlying cause for the observed changes in energy metabolism genes.

5.?Changes in hepatic gene expression provide new information on how a chicken's physiological mechanisms alter to cope with foot and hock lesions. The findings support other data indicating that birds with increased severity of lesions are likely to be in pain and that growth will be compromised. Reduction of the incidence of dermatitis by improved husbandry should therefore benefit both welfare and commercial performance.  相似文献   
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25.
The morphology of Onchocerca lupi, responsible for canine ocular onchocercosis, is unique within the genus. Earlier analyses of the 5S ribosomal RNA gene spacer region sequence of the parasite and the 16S ribosomal RNA gene sequence of its Wolbachia endosymbiotic bacteria (Rickettsiales) supported the morphological and biological arguments that O. lupi is a distinct species. However, the exact phylogenetic position of O. lupi and its endosymbiont could not be unambiguously determined. Herein we report analyses based on the mitochondrial cytochrome oxidase I (COI) gene of the filarial species and the Wolbachia surface protein (wsp) and the bacterial cell-cycle ftsZ genes of their wolbachiae. Our results indicate that O. lupi separated from other Onchocerca spp. early in evolution. This is in line with the previous morphological analysis demonstrating that O. lupi is an atypical Onchocerca species showing both primitive and evolved characters. The phylogenetic trees generated for the COI sequences of filariae and the wsp and ftsZ sequences of their wolbachiae were congruent with each other, which supports the hypothesis that nematodes and their Wolbachia endobacteria share a long co-evolutionary history.  相似文献   
26.
This study examined the plexus lumbalis and its branches in the sparrowhawk (Accipiter nisus). Fifteen sparrowhawks were used in this study. After administering an anaesthetic to the birds, the body cavities were opened. The birds were fixed with formaldehyde after draining of the blood. The nerves of the plexus lumbalis were dissected separately and photographed. The plexus lumbalis was formed by the union of the branches of the synsacral spinal nerves, which left from the ventrolaterale of os lumbosacrale. The plexus consisted of three (2nd, 3rd and 4th) synsacral spinal nerves. The cranial and caudal nerves originating from the plexus lumbalis were the nervus cutaneous femoris, nervus coxalis cranialis, nervus femoralis, nervus saphenus and nervus obturatorius. The general macroanatomical shape of the plexus lumbalis and the distribution of the nerves originating from this plexus were similar to those of other bird species.  相似文献   
27.
This report describes bilateral mammary gland infection with a previously unidentified Cephalobus species of nematode. Only one previous case of verminous mastitis due to a Cephalobus species has been reported, pre-dating the widespread use of molecular diagnostics. This report describes the case presentation and management, as well as the morphological and molecular methods of nematode identification.  相似文献   
28.
A variety of laboratory tests are available to assist the clinician in the assessment of kidney health and function. The majority of widely used tests are indicative of altered renal function, not becoming abnormal until function is significantly compromised. These include serum urea and creatinine concentrations, serum electrolyte concentrations, urine specific gravity (USG), fractional electrolyte excretion ratios and symmetric dimethylarginine (SDMA) concentrations. Some of these parameters may also be affected by nonrenal disease. The results of a further group of tests can indicate renal damage, but do not reflect renal function. These include urine tubular enzyme concentrations, urine protein concentrations, urine neutrophil gelatinase-associated lipocalin (NGAL) concentrations and cytological abnormalities.  相似文献   
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30.
A double antibody sandwich enzyme-linked immunosorbent assay (ELISA) was developed for measuring Aujeszky's disease virus (ADV) antigen concentration and an inhibition technique based on the former was developed for detection of antibodies to ADV. The results were checked by determining the cytopathic and serum neutralization titres. The correlation was satisfactory in both cases, with correlation coefficients above 0.8. When measuring ADV antigen concentration, the lower limit of detection was 10(3) TCID 50/0.2 ml. The sensitivity of ELISA in detecting antibodies to ADV was found to be superior to that of the serum neutralization test and, thus, enabled the testing of rabbit and guinea-pig sera.  相似文献   
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