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The vitamin A concentration was determined in 89 Australian brands of commercial foods for dogs and cats. It was found that 8% of the dog foods and 14% of the cat foods had concentrations of vitamin A below the minimum recommended 1.1 mg/kg dry matter (dm) for dogs and 1.8 mg/kg dm for pregnant or lactating cats. Canned and fish-labelled cat foods were the only varieties with less than the minimum recommended concentration of Vitamin A, of which 71% were the same brand. The minimum recommended concentration of vitamin A was exceeded in all canned dog food tested. Concentrations of vitamin A in dry (ca. 6% moisture) dog and cat foods and semi-moist dog foods (ca. 23% moisture) never exceeded 10 mg vitamin A/kg dm. In contrast, canned pet foods stated to contain liver or kidney showed vitamin A concentrations from 13 to 284 mg/kg dm.  相似文献   
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An indirect enzyme linked immunosorbent assay (iELISA) for diagnosis of anaplasmosis using undiluted individual milk samples from dairy cows was developed. The recombinant 19 kDa major surface protein 5 (rMSP5) of Anaplasma marginale was used as antigen. A monoclonal antibody against bovine IgG1 conjugated with peroxidase and the chromogen 3,5,3',5'-tetramethylbenzidine were used in the test. Strong and weak, positive and negative milk samples were set up as reference controls. Results were expressed as percentage of positivity (PP) contrasting with the strongest positive control. The test was evaluated in two groups (G1 and G2) of lactating dairy cows from herds located in A. marginale non-endemic areas of Argentina. The infection status of both groups, G1 (n=128) sampled after anaplasmosis outbreak, and G2 (n=216) free of anaplasmosis was established by polymerase chain reaction (PCR). Serum samples of cows from G1 and G2 were analyzed by card agglutination test (CAT) and competitive ELISA (cELISA), while the novel iELISA was evaluated in their corresponding milk samples. At a cutoff of 42 PP, the ELISA has 98% sensitivity and 95% specificity. A significant difference (P<0.0001) was found between the mean PP value of negative samples from G1 (17.4+/-14.9), and G2 (8.6+/-7.1). The agreement and kappa (kappa) value between iELISA and PCR was 96%, kappa=0.919; between iELISA and CAT was 97%, kappa=0.880; and between iELISA and cELISA was 97%, kappa=0.899. These results strongly support the usefulness of iELISA to detect A. marginale antibodies in milk. Additional studies are necessary to define the ability of the milk iELISA to detect not only acutely infected, but also carrier cattle.  相似文献   
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SUMMARY The effect of loss of weight on maintenance of acquired immunity to Trichostrongylus colubriformis in Merino sheep was assessed in 2 experiments. Adult Merino sheep with previously acquired immunity to T colubriformis were housed in individual pens. Sheep were infected 3 times weekly with 2000 T colubriformis larvae. A diet based on chopped oaten and lucerne hay (experiment 1) or a pelleted diet based on lucerne hay and grain products (experiment 2), was offered in amounts to sustain a moderate gain in body weight, or was reduced step-wise to cause a loss in body weight. Worm egg counts were determined weekly. The reduction in feed on offer resulted in a mean weight loss of 4.0 kg over 9 weeks (experiment 1) or 4.8 kg over 7 weeks (experiment 2). Based on worm egg counts, there was no indication of a change in immunity to T colubriformis in either of the experiments. These results suggest that acquired immunity to T colubriformis in adult sheep that are exposed to infection is maintained during periods of moderate loss of weight associated with inadequate nutrition.  相似文献   
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Plant Foods for Human Nutrition - Time-restricted feeding and food enriched in polyphenols are strategies to prevent or reduce metabolic disorders. Bean leaves (Phaseolus vulgaris L.) are a...  相似文献   
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Farber D  Baran P 《Science (New York, N.Y.)》1977,195(4283):1166-1170
Since we do not know of any completely workable solutions to the problems we have considered, we shall settle for a few general observations: 1) The public availability of socially useful computer communications services is and has been held back by legal battles that are now under way between the potential suppliers. 2) No simple resolution of these issues in the near future seems likely in view of the past conceptual separation of computers and communications doctrines. 3) The current policy is to determine whether the nation shall or shall not have certain computer communications services, by the adversary process. In this process, often only the voices of the loudest adversary suppliers are heard. 4) Although there can be no certainty that better alternatives cannot be devised, we believe that such a possibility assumes a higher probability if the key actors come from the technical community sectors more representative of the future consumers. 5) If we are to have the new services that are possible, we need an approach that makes better use of the technologists' dreams and goals rather than have future prospects excessively bound by lawyers paid to preserve the interests of their clients, irrespective of any secondary consequences. 6) We cannot be sanguine about this possibility, as technological statesmanship is too easily corrupted by the same forces that have placed us in this predicament. Furthermore, even if not corrupted, beneficial cooperation can too readily be regarded as simply collusion. 7) Although we do not have any clear answer, we do know that present approaches are not taking us where we want to go very rapidly and that alternative approaches should at least be considered.  相似文献   
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