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71.
Inclusion bodies, indistinguishable from rabies inclusion bodies (Negri bodies), were found in the brains of 8 nonrabid dogs. The inclusions were compared to Negri bodies present in neurons of rabies-positive animals and examined for the presence of rabies virus by a combination of immunoperoxidase staining (7 cases), fluorescent antibody (FA) staining (1 case), and transmission electron microscopy (4 cases). Positive immunoperoxidase staining for rabies was obtained in brain tissues from FA rabies-positive animals. All brain tissues from the 7 dogs stained by the immunoperoxidase method and the brain from the 1 dog stained by the FA method were negative for rabies. Rabies virus was not found in inclusion-containing neurons in the cases examined by transmission electron microscopy. These results emphasize the importance of FA testing and mouse inoculation for the diagnosis of rabies.  相似文献   
72.
Maiden heifers and lactating cows of known ovarian status and of several breeds were treated with a synthetic prostaglandin, cloprostenol, or a synthetic progestagen, norgestomet, at the start of an artificial insemination (AI) program. Animals in the cloprostenol treatment received 2 injections 10 days apart. Over the next 26 days those animals that showed oestrous behaviour were inseminated. Synchronisation rates and calving rates to insemination over the first 7 days were calculated. Those in the norgestomet treatment received an implant of norgestomet plus an injection of norgestomet and oestradiol valerate. The implant was removed 10 days later and the animals were given an injection of pregnant mare serum gonadotrophin (PMSG). They were inseminated at 48 h (maiden heifers) or 56 h (lactating cows) after implant removal. Calving rates to fixed-time insemination were recorded. After completion of the AI program the animals in both treatments were joined with bulls. Overall calving rates (AI plus bulls) were calculated. By day 7 of the program, 82% of the maiden heifers and 76% of the lactating cows in the cloprostenol treatment had been detected in oestrus. By day 21 the respective figures were 99% and 81% Norgestomet treatment had an immediate and a prolonged effect on ovarian activity in those females classified as having inactive ovaries at the start of the AI program. Calving rates of those females to fixed-time AI and overall were similar to those of the females with active ovaries in both treatments. Their calving rates to fixed-time insemination, and overall calving rates for the lactating females, were significantly higher than the corresponding values of their contemporaries treated with cloprostenol and inseminated on observed oestrus over 7 days. For those females classified as having active ovaries at the start of the AI program, calving rates to first insemination and overall were similar for both treatments. Overall calving rates of lactating cows of each breed were, with one exception, higher in the norgestomet treatment than in the cloprostenol treatment. Although norgestomet treatment was more expensive than cloprostenol treatment, the advantage in calf crop resulted in an overall monetary advantage to the norgestomet treatment.  相似文献   
73.
Several cases of hydatid echinococcosis were diagnosed in a laboratory colony of 19 pig‐tailed macaques (Macaca nemestrina) at the Paul Ehrlich Institute, Germany. Three hydatid cysts were found in the liver of an euthanized animal. The diagnosis of an Echinococcus granulosus infection was confirmed by histopathology and the results of a specific polymerase chain reaction. The serum of five of 14 other monkeys tested for Echinococcus antibodies using a genus‐specific enzyme‐linked immunosorbent assay (ELISA) was positive or weakly positive; none of the animals, however, showed specific reactions in an E. multilocularis‐specific ELISA. On ultrasonographic examination, alterations in the liver were found in four of the serologically positive monkeys, and two animals showed clinical signs such as progressive anorexia, apathy and icterus. The monkeys had most probably acquired the E. granulosus infection in their breeding colony in Slovenia.  相似文献   
74.
Testosterone concentrations in stallions showed a seasonal trend with peak concentrations in the spring (April and May in Britain) and lowest concentrations in the period from December to February. The effect on this pattern of changing the length of the photoperiod at the end of the normal breeding season (mid-summer's day) was studied in 2 experiments. In the first experiment artificial illumination was organised from 21 June to mimic the effect of transfer to a southern hemisphere spring and summer, that is short days becoming longer. The stallions had low concentrations of testosterone in February and high concentrations in April. Concentrations in July, August and September were extremely low with a return to high values in late November/early December. In the second experiment, illumination was maintained at the equivalent of a 16 1/2-hour day from 21 June to mid December. These stallions had high testosterone concentrations in April, after which they fell until August, later rising to a maximum in October. These results are discussed in relation to transfer of stallions between the northern and southern hemispheres.  相似文献   
75.
76.
The objective of this experiment was to determine whether alkaline hydrogen peroxide-treated oat hulls (termed oat fiber; OF) are nutritionally efficacious as a source of dietary fiber in meat-based dog foods. Thirty female English Pointers were assigned in a completely randomized design to isonitrogenous diets. Treatments were 1) control diet, 2) 7.5% added beet pulp (BP), and 3) 2.5, 4) 5.0, and 5) 7.5% added OF. Inclusion of 7.5% BP increased (P less than .05) DM intake and decreased (P less than .05) digestibility of DM and OM compared with the control. Dry matter intake increased (P less than .05) with increasing level of OF and digestibility of DM, OM, and total dietary fiber (TDF) decreased (P less than .05). Digestibility of DM, OM, and TDF were higher for dogs fed the 7.5% BP than for those fed the 7.5% OF treatment. Digestible energy, expressed as a percentage of GE, was greater for the control treatment than for the 7.5% BP treatment. A linear decrease in DE (percentage of GE) was noted as the concentration of OF increased, and the DE value (percentage of GE) for the 7.5% BP treatment was greater (P less than .05) than that for the 7.5% OF treatment. A linear decrease (P less than .05) was noted in ME, expressed as a percentage of GE, as the level of OF increased. Frequency of defecation and mean retention time were unaffected (P greater than .05) by treatment. Oat fiber was an effective substitute for BP in dog diets.  相似文献   
77.
78.
Intramedullary pressure in canine long bones   总被引:1,自引:0,他引:1  
Intramedullary pressure was measured bilaterally in 36 dogs: in the diaphysis and distal metaphysis of the femur, in the proximal metaphysis of the tibia and humerus, and in the diaphysis of the radius. Pressure measurements were repeated in 5 dogs, 14 days after the initial recordings. Mean (+/- SD) pressures in the femoral diaphysis and distal metaphysis were 27.6 (+/- 15.4) mm of Hg and 17.6 (+/- 10.5) mm of Hg, respectively. Mean (+/- SD) pressures in the tibial diaphysis and proximal metaphysis were 26.4 (+/- 13.0) mm of Hg and 17.9 (+/- 11.8) mm of Hg, respectively. Mean (+/- SD) pressures in the humeral diaphysis and proximal metaphysis were 26.2 (+/- 15.8) mm of Hg and 13.4 (+/- 7.7) mm of Hg, respectively. The mean (+/- SD) pressure in the radial diaphysis was 15.4 (+/- 18.9) mm of Hg. Metaphyseal pressure was significantly (P less than 0.05) lower than diaphyseal pressure. Repeated pressure measurements in 5 dogs did not vary significantly from initial values, suggesting that the wide range of pressure was real not artifactual.  相似文献   
79.
The nature of the hyperlipemia in two 3-week-old male kittens, one of which was presented with the owner's complaints of retarded growth and white streaks on its eyes, was studied. Hypertriglyceridemia, hypercholesterolemia, and reduced Post-Heparin Plasma Lipolytic Activities (PHPLA) were observed in both animals. One of the kittens, however, was more severely affected and in addition, had lipemia retinalis and a marked lactescent, hyperchylomicronemic serum in spite of a short-term fast before sampling. These findings are strikingly similar to those found in human Type I hyperlipoproteinemia due to familial Lipoprotein Lipase (LPL) deficiency. Diagnosis of persistent hyperlipemic syndromes in kittens should include the possibility of LPL deficiency as determined by PHPLA measurements.  相似文献   
80.
The California Egg Quality Assurance Program uses the delayed secondary enrichment culture method for detecting Salmonella Enteritidis in environmental drag swabs obtained from commercial layer complexes. The turnaround time for this method is variable and is dependent on the prevalence of Salmonella, level of the Salmonella identification, and capabilities of the performing laboratory. On a sample basis, a range of 4 to 8 days is required to identify a Salmonella sp. to the serogroup level. Additional time is required to serotype group D Salmonella isolates. A Salmonella Enteritidis-specific polymerase chain reaction (PCR) assay was developed for use on drag swabs and chick box papers, and had a turnaround time of 3-4 days. The delayed secondary enrichment culture method and the Salmonella Enteritidis-specific PCR assay were compared on 942 drag swab and 85 chick box paper samples submitted from 217 and 22 premises, respectively, as part of the California Egg Quality Assurance Program. The PCR assay identified 43 positive Salmonella Enteritidis samples from 22 premises, whereas the culture method identified 24 group D Salmonella-positive samples from 16 premises. There was a significant difference (P = 0.001) in the proportion of positive samples as determined by the two assays. Complete serotyping of the group D Salmonella-positive cultures confirmed Salmonella Enteritidis in all but one sample that was identified as Salmonella Jamaica and was negative by the PCR assay.  相似文献   
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