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111.
PRIMARY BONE TUMORS IN THE CAT:   总被引:1,自引:0,他引:1  
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112.
Five potato cultivars of autumn crop, dipped in corn oil, were observed for 90 days at room temperature under natural light. Chlorophyll formation took place in minute quantities in treated tubers of ‘Désirée’ and ‘Prima’, and a little more in ‘Primura’, ‘Montana’ and ‘Multa’, whereas all control tubers became completely green after 90 days. Sugars were significantly lower and starch higher in treated tubers than in controls. No sprout-development was observed in treated tubers of all cultivars, but 50–70% control tubers had sprouted during this period. Peeling-losses were minimum in treated tubers and were 67.5–85.4% in controls. The oil-dipped potato tubers of all cultivars could safely be stored for 60 days without quality deterioration under ordinary conditions of temperature and light.  相似文献   
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SONOGRAPHY OF THE EQUINE PALMAR METACARPAL SOFT TISSUES   总被引:2,自引:0,他引:2  
It was hypothesized that ultrasonography may be a sensitive method for identifying pathologic changes in the tendons and ligaments of the palmar metacarpus of the horse. The palmar meta-carpi of equine cadavers and live horses were examined sonographically. The advantages and disadvantages of various ultrasound scanning techniques and the normal appearance of longitudinal and transverse palmar metacarpal sonograms are described.  相似文献   
117.
In two experiments, a pour-on application of phosmet at 25 mg kg?1 reduced the harassment of cattle by black flies for up to 5–6 weeks posttreatment. During this period, the treated groups either gained more weight or loss less weight than their controls. The untreated groups made compensatory gains when teh black fly activity decreased or ceased. No significant differences existed between the average daily gains of a treated group and its control either for the posttreatment-periods of 9 and 15 weeks or for the experimental periods of 15 and 20 weeks in the two experiments.Black fly toxemia was not seen in indigenous cattle or in naive steers brought into a black fly infested area 1–2 weeks before the onset of black fly activity.  相似文献   
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Our study focused on the evaluation of the pharmacological and toxicological effects of plasmid-mediated GHRH supplementation with electroporation in normal adult dogs over a 180-d period. Twenty-eight dogs (< 2 yr of age) were randomized to four groups. Three groups (four dogs/sex for each group) were treated with ascending doses of GHRH-expressing plasmid: 0.2, 0.6, and 1 mg. One group (two dogs of each sex) served as the control. Clinical observations and body weights were recorded. Hematological, serum biochemical, and urine analyses were performed. Serum IGF-I, ACTH, and insulin were determined. Necropsies were performed on d 93 and 180; organs were weighed and tissues were fixed and processed for light microscopy. Selected tissues were used to assess plasmid biodistribution on d 93. At all doses, plasmid GHRH caused increased weight gain (P < 0.001), without organomegaly. Serum glucose and insulin in fasted dogs remained within normal ranges at all time points. Adrenocorticotropic hormone was normal in all groups. Significant increases in number of red blood cells, hematocrit, and hemoglobin (P < 0.01) were observed. In conclusion, our study shows that plasmid-mediated GHRH supplementation is safe in electroporated doses up to 1.0 mg in young healthy dogs.  相似文献   
120.
Three anthelmintics were compared for efficacy in reducing the egg production of Anoplocephala perfoliata in a herd of central Texas horses. Two trials were run, 1 in mares and the other in weanlings that were diagnosed as being infected with Anoplocephala by recovery of eggs in 5 g of feces with sugar centrifugation. Each animal was evaluated twice before treatment and again twice following treatment (at weeks 2 and 4 after treatment). The criteria for infection were the recovery of eggs on at least 1 occasion before treatment and the finding of eggs on 1 day following treatment. The mares were treated 1 time with either pyrantel pamoate at 13.2 mg/kg, nitazoxanide at 100 mg/kg, praziquantel at 1.23 mg/kg or remained as untreated controls. The weanlings were treated with pyrantel at 13.7 mg/kg nitazoxanide at 100 mg/kg or remained as untreated controls. The percentage reduction of patient infection in mares after treatment with pyrantel was 83%, with nitazoxanide was 78%, and with praziquantel was 83% and in controls was 17%. There was a 75% reduction of patient weanlings treated with pyrantel or nitazoxanide and a 17% reduction in untreated controls. The reduction of infection in all horses treated with any drug was significantly different from controls. All of the drugs were somewhat effective in the control of Anoplocephala, and there were no differences among the drugs in their effectiveness.

Introduction

Anoplocephala perfoliata, the lappeted tapeworm, is an inhabitant of the intestine of equids. Adult tapeworms attach to the intestinal mucosa at the ileocaecal valve and, when present in large numbers, cause edema and hypertrophy of the ileum. The disease manifest by this infection may be inapparent or may give rise to colic (abdominal pain) in the horse apparently from mechanical obstruction or intussusception of the small intestine into the caecocolon.1, 2, 3, 4, 5, 6, 7 and 8 The prevalence of infection is geographically variable9, 10, 11, 12 and 13 but appears to be increasing,14 with a much higher rate of infection found with necropsy as opposed to fecal observations. Horses become infected by the ingestion of infected orbatid mites in pastures. Orbatid mites, the intermediate hosts, are predatory and are found in decaying organic material, such as leaf litter. Horses of all ages are infected, but there are lower numbers of clinical cases in horses older than 4 years of age.4 The intensity of infection is highest in the late summer and autumn.8 and 12 Anthelmintics with reported efficacy against A perfoliata include pyrantel pamoate at 13.2 mg/kg,10 pyrantel tartrate at 2.6 mg/kg for 30 days,15 pyrantel embonate at 38 mg/kg,16 and praziquantel at 1 to 2 mg/kg.17 and 18 Nitazoxanide has not been evaluated for Anoplocephala but was included in the trial because of its effects against nematodes and tapeworms in humans.19 Because Anoplocephala infections may cause disease and there is a perception that current anthelmintics may not be as effective as in the past, a study was done to compare anthelmintics to lower the intensity of fecal egg counts in a herd of horses in central Texas.

Materials and methods

Quarter horse mares and weanlings from a single herd were evaluated with 5 g of feces with a sucrose double centrifugation test to determine whether eggs of Anoplocephala were present.20 Feces from each individual horse were evaluated twice, once approximately 2 weeks before treatment and again on the day of treatment. If Anoplocephala eggs were found on either date, the horse was considered to have positive results. Within each group (mares or weanlings), the treatment selection was randomly allocated as the horses were restrained for treatment. Fecal samples were again evaluated at 14 and 28 days after treatment for the presence or absence of eggs on either day.The dose for each individual horse was determined by chest girth weight tape at the time of treatment. The treatments were as follows: pyrantel pamoate (Strongid-T, Pfizer Animal Health, Exton, Pa) at 13.7 mg/kg via nasogastric intubation (12 mares, 8 weanlings), nitazoxanide oral paste (Nitazoxanide, Idexx Laboratories, Westbrook, Me) at 100 mg/kg (9 mares, 8 weanlings), praziquantel (Droncet injectable, Bayer Corp, Shawnee Mission, Kan) at 1.23 mg/kg via nasogastric intubation (6 mares), and untreated controls (6 mares, 6 weanlings). A 1-tailed Fisher exact test was used to compare rates of infection before and after treatment. If a mare or foal did not have positive results before treatment, it was not evaluated in this study.

Results and discussion

No abnormal clinical signs were seen after treatment with any of the products. Treatment was administered to several additional animals with each product, but they were not included in the analysis if they did not have positive results on 1 of the 2 evaluations before treatment, hence, the different numbers of horses in treatment groups.None of the horses in the trial exhibited clinical signs associated with the infection of A perfoliata. However, before the trial, a mare from the infected herd exhibited signs of colic and Anoplocephala eggs were detected in the feces. Examination of the remainder of the herd gave impetus to the study.Mean egg counts before and after treatment are given in the Table.The presence of strongylate and Parascaris eggs in weanlings served as a control of the methodology of evaluation. The difficulty of finding Anoplocephala eggs has been recognized by several authors,5, 8, 13, 14 and 21 but the authors also recognize that when there were greater numbers of parasites there was increased egg production. Therefore, finding of eggs with fecal flotation indicated that there were 20 worms or more. However, there appears to be no correlation between the number of worms and egg counts once the detection threshold is reached,22 so the criterion for evaluation was the presence of eggs in the feces before treatment compared with after treatment. Although mean egg counts were not compared, the number of eggs in each infected horse was less after treatment in all groups compared with untreated controls (Table). The method of evaluation used in this study cannot be equated to those of critical10 and 16 or control14 studies in which horses are killed so that all worms are detected. However, the use of clinical studies to compare compounds is useful in detecting which anthelmintics are likely to be of value against geographically distinct populations of worms. Admittedly, more sampling may have increased the number of horses with positive results, both before and after treatment.  相似文献   
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