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51.
A rapid procedure for determining tuber maturity and processing quality using a blood glucose monitor is outlined. The procedure is simple to use, inexpensive and gives acceptable percent glucose and sucrose rating (SR) values for commercial applications. The procedure has been used successfully for determining the best time to sell commercial quantities of stored tubers (cvs. Norchip, Niska) for processing as chips in Alberta.  相似文献   
52.
Ascaridia dissimilis, a roundworm in turkeys, has been noted with increased frequency in commercial turkeys. Because infected turkeys can shed A. dissimilis ova in their feces, the potential exists for the external surface of turkey eggshells to be contaminated with A. dissimilis ova. The objectives of this study were to determine the presence of and recover A. dissimilis ova on the external surface of the turkey egg. In Experiment 1, turkey eggs were collected from naturally infected flocks, and eggs were processed by a sodium hydroxide procedure to recover any A. dissimilis ova on the external egg surface. In Experiment 2, the external surface of the turkey eggs was inoculated with 116 A. dissimilis ova/g feces, and eggshells were sampled every 3 days until 28 days of incubation to assess the recovery of A. dissimilis ova from the eggshell. In Experiment 1, of the 36 eggs examined from a flock naturally infected with A. dissimilis, one egg had an A. dissimilis ovum on its external eggshell surface. Experiment 2 demonstrated that A. dissimilis ova can be recovered from the external egg surface after a 28-day incubation period in the incubator. Ova recovery declined from an average of 62 A. dissimilis ova/turkey egg at day 2 of incubation to an average of 3 A. dissimilis ova/turkey egg at day 28 of incubation.  相似文献   
53.
ABSTRACT: A facile synthesis of Tyrian purple, a valuable purple dye derived from gastropod mollusks in ancient times, has been accomplished. Tyrian purple, 6,6'-dibromoindigo, was easily obtained by three steps of reactions from the commercially available 6-bromoindole, on the basis of a biosynthetic pathway of indigo and biological precursors of the purple. Iodination of 6-bromoindole, followed by acetoxylation with silver acetate in acetic acid, afforded 6-bromo-3-acetoxyindole, whose alkaline hydrolysis accompanying air oxidation produced Tyrian purple.  相似文献   
54.
55.
A flock of breeding ring-necked pheasants received feed with a high selenium content. Within 4 days of eating the toxic feed, the rate of egg production began to decrease, and bird aggression increased. Approximately 12% of the hens died within a week. Necropsy of the hens revealed colorless fluid around the heart and a friable, but otherwise normal, liver. The rapid onset of the problem and signs noted at necropsy suggested toxicosis. Based on analysis, the feed contained 9.3 ppm of selenium. Selenium toxicity was consistent with the histologic diagnosis of degenerative cardiomyopathy, vacuolar degeneration of hepatocytes, and centrilobular hepatic necrosis. After 8 days, the toxic feed was removed and replaced with fresh feed. Egg production, which had dropped to 50%, returned to normal within 10 days of feed replacement. Hatchability of eggs laid from days 8 to 14 after delivery of the toxic feed was 35%. Approximately 10% of the chicks that hatched had deformed beaks and abnormal eyes. Many of the chicks that died in the shell had deformities, bringing the total to more than 50% of all embryos that developed. The selenium content of eggs that had no embryonic development was 2.05 ppm. Hatchability of eggs laid from days 21 to 28 after the toxic feed was delivered was almost 80%, which was slightly lower than normal. The selenium content of these eggs was 0.30 ppm. These results show the rapid onset and correction of selenium toxicity and suggest that specific embryologic defects are diagnostic for selenium toxicity.  相似文献   
56.
Riemerella anatipestifer is a gram-negative bacteria that can cause disease in a wide variety of wild and domesticated birds, especially waterfowl. The infection can be peracute, acute, or chronic. Although various routes of transmission have been proposed, to date, there is little information on the effects of route of transmission and challenge dosage on R. anatipestifer infection. Hence, the objective of this study was to determine the effect of route of inoculation and challenge dosage on R. anatipestifer infection and pathology. To achieve this objective, one hundred forty-seven 14-day-old white Pekin ducks (Anas platyrhynchos) were equally divided into 13 experimental groups (12 challenge and 1 control group). Each challenge group had 11 ducks. The control group had 15 ducks. Four routes of inoculation were evaluated (intranasal, oral, subcutaneous, and intravenous). Three dosage levels were evaluated for each inoculation route (10(2), 10(4), and 106 colony forming units [CFU]/ml). At the 106 CFU/ml dosage level, mortality was most associated with the subcutaneous (91%) and intravenous (82%) routes, followed by the nasal (18%) and oral (9%) routes. A unique pathologic lesion was found in the bursa of Fabricius and spleen of affected birds. Within the spleen and bursa of Fabricius, there were varying degrees of lymphoid depletion and necrosis within the cortical and medullary regions. These pathologic lesions have not been previously reported in ducks with R. anatipestifer infection.  相似文献   
57.
There has been limited research on the prevalence of foodborne pathogens such as Escherichia coli O157:H7, Salmonella, and Campylobacter on ostrich carcasses. Likewise, few studies have been done in ostriches to determine the antimicrobial susceptibilities of common bacteria, like E. coli. In this study, ostrich carcasses were sampled from eight slaughterhouses in Ohio and one in Indiana. Although results demonstrated no E. coli O157:H7 from the carcasses sampled, 91% (116/128) of the dressed carcasses sampled had E. coli present. One carcass sample (1/152) was positive for Salmonella. Campylobacter were detected in 10% (19/191) of the carcasses. Antimicrobial susceptibility testing on 93 carcass E. coli isolates showed resistance to erythromycin (99%), neomycin (65%), netilmicin (2%), oxytetracycline (22%), streptomycin (2%), and trimethoprim (3%). All isolates were resistant to bacitracin, lincomycin, penicillin, and vancomycin. For the large intestinal sampling, 149 of the 217 (69%) samples had E. coli present. Fifty of these 149 samples had E. coli levels ranging from 10(2) to 10(5) colony-forming units/g feces. Campylobacter were isolated from 6 of 201 (3%) samples. No Salmonella colony was detected. Antimicrobial susceptibility testing on 131 intestinal E. coli isolates showed resistance to erythromycin (98%), neomycin (66%), netilmicin (34%), oxytetracycline (34%), streptomycin (40%), and trimethoprim (13%). All isolates were resistant to bacitracin, lincomycin, penicillin, and vancomycin.  相似文献   
58.
The epidemiologic features of feline immunodeficiency virus (FIV) infection were evaluated in 2,765 cats from the United States and Canada. Of these cats, 2,254 were considered by veterinarians to be at high risk for the infection, and 511 were healthy cats considered to be at low or unknown risk. Of the cats in the high-risk group, 318 (14%) were found to be infected with FIV. The infection rate among low- or unknown-risk cats was 6 of 511 (1.2%). Male cats in the high-risk group were 3 times more likely to be infected than were females, similarly as were cats greater than 6 years old, compared with younger cats; domestic cats, compared with purebred cats; and free-roaming cats, compared with confined cats. Feline immunodeficiency virus and FeLV infections did not appear to be linked with each other; 16% of FeLV-infected cats in the high- and low-risk groups were coinfected with FIV. In contrast, there was a pronounced linkage between FIV and feline syncytium-forming virus (FeSFV) infections. Seventy-four percent of FeSFV-infected cats in the high-risk study group were coinfected with FIV, compared with a 38% FIV infection rate among cats that were not infected with FeSFV. The major clinical manifestations associated with FIV infection in cats that were surveyed included chronic oral cavity infections (56%), chronic upper respiratory tract disease (34%), chronic enteritis (19%), and chronic conjunctivitis (11%). Bacterial infections of the urinary tract (cystitis), skin, and ears were seen in a small proportion of cats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
59.
Brain perfusion computed tomography (CT) scanning was performed in a mongrel dog and a golden retriever that were diagnosed with third ventricular tumor and olfactory bulb tumor, respectively, by contrast-enhanced CT. The tumors were pathologically diagnosed as ependymoma and meningioma, respectively. Perfusion CT results revealed that the ependymoma in this study had a lower blood flow, higher blood volume, and greater transit time of blood than the adjacent brain tissue. Further, the meningioma in this study had a higher blood flow, higher blood volume, and greater transit time of blood than the adjacent brain tissue. Perfusion CT can potentially be used for the grading of brain tumors and narrowing differential diagnosis, provided the perfusion CT data of animals are accumulated.  相似文献   
60.
1. The gut microflora of chicks fed on a purified diet containing 300 g lactose plus 300 g starch/kg was compared with that of control birds receiving a diet containing 600 g starch/kg.

2. In 14‐d‐old conventional chicks, lactose in the diet decreased the incidence of lactobacilli and clostridia in the caecal contents, although when present in lactose‐fed chicks the counts of lactobacilli exceeded those of control chicks.

3. High counts of Proteus sp. were present in the caeca of control birds but they were completely suppressed in conventional birds fed on the lactose diet. In vitro tests showed that this inhibition was partially due to Escher‐ichia coli and Streptococcus faecalis.

4. The growth of Lactobacillus acidophilus was inhibited by lactose when gnotobiotic chicks were monoassociated but not when polyassociated. The protective effect was shown in vitro to be due to L. salivarius.

5. The pH was markedly lowered in the caecum of conventional and polyassociated chicks receiving dietary lactose. Of the strains used in gnotobiotic experiments E. coli, S. faecalis and L. salivarius produced the lowest pH values in the caeca.  相似文献   

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