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During 65 d of storage a gradual increase in fungal activity (evaluated by CO2 production) was observed in a diet with its moisture content elevated to 136 g/kg. This activity was inhibited by supplementation of the wetted diets with either calcium propionate (3 g/kg) or Agrosil (2 g/kg). The fat content of the wetted untreated diet decreased between the 18th and the 45th d of storage from 38 to 29 g/kg. This change was prevented by the addition of either of the two fungistats. The weight gains of 7-d-old female broiler chicks fed on the wetted diets with or without the fungistats from the 18th d after their preparation for 27 d, did not differ significantly (P greater than 0.05) from those of birds fed on the unwetted diet. However, the food:gain ratio of chicks fed on the unwetted diet was significantly (P less than 0.05) better than that of chicks fed on the fungistat-free wetted diet. The results from birds fed on the fungistat-supplemented wetted diets were intermediate. It is concluded that the early stages of fungal activity (characterised by increased CO2 production, without changes or with only a slight decrease in fat content) have only a minor effect on the nutritional value of diets.  相似文献   
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OBJECTIVE: To estimate prevalence of canine hip dysplasia (CHD) in Golden Retrievers and Rottweilers and identify sources of bias in published reports. DESIGN: Prospective study. ANIMALS: 200 clinically normal Golden Retrievers and 140 clinically normal Rottweilers between 24 and 60 months of age referred for hip evaluation (group 1) and 93 clinically normal dogs evaluated for Orthopedic Foundation for Animals (OFA) hip certification (group 2). PROCEDURE: Hip-extended pelvic radiographs from group 1 dogs were screened for CHD. Radiographs were evaluated twice; the first interpretation used an OFA-type subjective 7-point scoring system, and the second included the caudolateral curvilinear osteophyte as an additional sign of degenerative joint disease. The OFA submission rate of group 2 dogs was determined from the number of official reports returned from the OFA. RESULTS: Prevalence of CHD in Golden Retrievers ranged from 53% to 73% and in Rottweilers ranged from 41% to 69%. Among dogs referred for OFA evaluation, radiographs from 49 (53%) were submitted to OFA. Of submitted radiographs, 45 (92%) were normal; of radiographs not submitted, 22 (50%) were normal. Radiographs with normal-appearing hips were 8.2 times as likely to be submitted to the OFA. Compared with Golden Retrievers, Rottweiler radiographs were significantly more likely to be submitted for OFA certification. CONCLUSIONS AND CLINICAL RELEVANCE: Prevalence of CHD in these 2 breeds may be much higher than previously reported in the United States. Results suggest substantial bias in the OFA database, which causes lower estimates of prevalence of CHD.  相似文献   
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Gibberellic acid: a growth factor in the unicellular alga Gymnodinium breve   总被引:1,自引:0,他引:1  
Gibberellic acid stimulates growth in the unicellular alga Gymnodinium breve (dinoflagellate). The maximum effect was obtained with 10(-7) molar gibberellic acid, whereas concentrations greater than 5 x 10(-7) mole per liter were inhibitory. The effect of the compound is observed as a marked shortening of the lag period, which is normally 6 to 8 days after innoculation.  相似文献   
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Hypothalamic-releasing factors regulate the secretion of anterior pituitary hormones. The anterior pituitary gland secretes the same six hormones as found in mammals: FSH, LH, prolactin, GH (somatotropic hormone), ACTH, and TSH, plus the melanotropic hormone. The endocrine hormones of the avian posterior pituitary gland concerned with reproduction are mesotocin and AVT. The pineal gland, through the secretion of the hormone melatonin, modulates the periodic autonomic functions of the central nervous system. The ovary produces estrogens, progestogens, and androgenic compounds. The testes produce testosterones and progesterone. The thyroid glands produce two hormones, T4 and T3. The avian adrenal glands produce corticosterone and aldosterone. The bursa of Fabricius is considered an endocrine organ since it is involved in the production of humoral factors. The male reproductive system undergoes hormonal changes associated with puberty, the breeding season, and molt. Some avian species undergo a type of disintegration and seasonal reconstruction of the testis and epididymis. The relationship of the ovarian follicular hormones and the plasma hormones varies depending on the stage of the reproductive cycle and the seasonal photostimulation. Female birds may conceive in the absence of a mate as a result of the fertile period phenomena. The blood chemistry of laying birds is different from that seen in nonlaying hens. Domestication has had a definite influence on the hormone cycles of some avian species. This may lead to certain reproductive problems.  相似文献   
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The toxicity of allyl alcohol as a fumigant was assessed for adults ofTribolium castaneum (Herbst.),Rhyzopertha dominica (F.) andSitophilus oryzae (L.). Fumigations were carried out in 3.4–1 glass containers at concentrations of 1–15 mg/l for 3 h. The most sensitive species wasS. oryzae and the most tolerant wasT. castaneum. A dose of 15 mg/l for 3 h was lethal to all three species tested. The feasibility of proposing allyl alcohol as a candidate fumigant is discussed. Publication of the Agricultural Research Organization.  相似文献   
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OBJECTIVE: To evaluate the effects of diet restriction on development of radiographic evidence of hip joint osteoarthritis in dogs. DESIGN: Longitudinal cohort study. ANIMALS: 48 Labrador Retrievers from 7 litters. PROCEDURES: Forty-eight 6-week-old puppies from 7 litters were paired with littermates by sex and weight, and each pairmate was randomly assigned to 1 of 2 groups of 24 dogs each. Starting at 8 weeks of age, 1 group was fed ad libitum (control fed) and the other was fed 25% less (restricted fed) of the same diet for life on a pairwise basis. The dogs' hip joints were radiographed in the standard ventrodorsal hip-extended view at multiple intervals prior to 1 year of age and at annual intervals thereafter on the basis of birth anniversary. A board-certified radiologist unaware of group assignment scored the radiographs for evidence of osteoarthritis. RESULTS: Prevalence of radiographic evidence of hip joint osteoarthritis in all dogs increased linearly throughout the study, from an overall prevalence of 15% at 2 years to 67% by 14 years. Restricted-fed dogs had lower prevalence and later onset of hip joint osteoarthritis. Median age at first identification of radiographic evidence of hip joint osteoarthritis was significantly lower in the control-fed group (6 years), compared with the restricted-fed group (12 years). CONCLUSIONS AND CLINICAL RELEVANCE: Restricted feeding delayed or prevented development of radiographic signs of hip joint osteoarthritis in this cohort of Labrador Retrievers. Lifetime maintenance of 25% diet restriction delayed onset and reduced severity of hip joint osteoarthritis, thus favorably affecting both duration and quality of life. In addition, the data indicated that development of hip joint osteoarthritis was not bimodal in these dogs but occurred as a continuum throughout life.  相似文献   
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Shipments of corn imported to Israel from the U.S.A. during 1985 were sampled during unloading and examined for the presence of fungi and the trichothecene deoxynivalenol (DON). The most frequent species found on the corn wasAspergillus flavus followed byA. versicolor; three otherAspergilli — A. niger, A. ochraceus andA. fumigatus — were found at a much lower frequency. DON analysis was performed by electron capture detection gas chromatography after derivatization with heptafluorobutyryl imidazole. At fortification levels of 0.1, 1 and 2 μg/g, recoveries of 80—100% were obtained. Although DON was not detected in any of the samples analyzed, the observation (in the shipments) of fungi belonging to the generaFusarium andAspergillus suggests a potential danger of mycotoxin contamination. The relatively high moisture content of the samples increased the likelihood of such a hazard.  相似文献   
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