PURPOSEThe Agency for Healthcare Research and Quality (AHRQ), formerly known as the Agency for Health Care Policy and Research (AHCPR), announces its continued interest in supporting the health services dissertation research small grant program.
Note: Contents data are machine generated based on pre-publication provided by the publisher. Contents may have variations from the printed book or be incomplete or contain other coding.
The information to develop a specific recommendation for the vitamin K requirement of guinea pigs does not exist. The menadione content of some of the more frequently used diets ranges from 12 to 58 µmol/kg diet (Reid and Briggs, 1953; Navia and Lopez, 1973; O'Dell et al., 1989). These diets appear to be adequate to prevent hemorrhages, but no information is available about more sensitive indicators of vitamin K status. Based on limited information, a concentration of 5 mg phylloquinone/kg diet (11 µmol phylloquinone/kg diet) is suggested.
Signs of Vitamin D Deficiency Guinea pigs fed diets with a normal calcium-to-phosphorus ratio do not develop gross signs of vitamin D deficiency (Kodicek and Murray, 1943). However, Sergeev et al. (1990) observed many changes in vitamin D status of guinea pigs fed a vitamin D-deficient diet containing 6 g calcium/kg diet and 6 g phosphorus/kg diet. Serum calcium and phosphorus concentrations were reduced, serum alkaline phosphatase was increased, serum 25-hydroxycholecalciferol concentrations were extremely low, kidney 1-α-hydroxylase activity was more than twice the normal concentrations, active transport of calcium in the duodenum was decreased, and bone calcium content was about four-fifths the control concentrations. Administering 5.2 nmol (15 IU) of cholecalciferol per animal every other day prevented the development of these signs. This is about twice the amount available from typical diets. Lower amounts were not used. A deficiency of ascorbic acid also altered the animal's ability to metabolize vitamin D. Howe et al. (1940) housed guinea pigs in a darkened room and fed them a low-vitamin D purified diet with 0.28 g Ca/kg and 2 g P/kg. In addition to retarded growth, typical lesions occurred in the zone of cartilage proliferation at the epiphyseal plate of long bones and ribs. Also, incisors exhibited a high degree of enamel hypoplasia, and enamel and dentin were disorganized and irregular with poor calcification.
Reports of protein deficiency produced by lowering the protein content of diets fed to adult guinea pigs during reproduction or maintenance were not found. Reducing the intakes of both protein and energy by restricting the intake of adequate protein diets (300 g casein or 185 g plant protein/kg) to 20 to 50 percent during the last half of gestation resulted in premature delivery, reduced weight for pups, and death of most pups within the immediate postnatal period (Apgar and Everett, 1991b). Reduced litter size was reported when feed was restricted to 40 percent of normal ad libitum intake beginning at day 30 of gestation (Young and Widdowson, 1975).
Other ConditionsThe following conditions apply to dissertation grants:A Principal Investigator who discontinues or suspends a project during the grant period must inform the AHRQ immediately in writing.
In the laboratory, the guinea pig's diet is much higher in energy density and lower in fiber content than the diet of green vegetation and fruits it consumes in the wild. The guinea pig consumes many small meals throughout the day, is fastidious in choice of foods, and may resist abrupt changes in composition or form of the diet. Animals fed pelleted natural-ingredient diets often do not readily accept a powdered purified diet unless introduced gradually. Pelleting the powdery diet (Ostwald et al., 1971), moistening the food with water (O'Dell and Regan, 1963; Singh et al., 1968), and using gel diets (Navia and Lopez, 1973; Apgar and Everett, 1991b) have been successful in promoting diet acceptance. These behavioral characteristics and special nutritional requirements need to be considered when designing nutritional or metabolic studies.
Project Description: The applicant must provide a narrative project description (not to exceed 10 pages in sections 2-5 of the Research Plan) that contains a detailed scientific and technical discussion of the following specific points:
In its natural habitat this herbivorous animal consumes large quantities of vegetation (Navia and Hunt, 1976). The molar teeth are especially suited to grinding and, like other species of rodents, the guinea pig has open-rooted incisors that grow continuously throughout its life. Like the rat, mouse, and rabbit, the guinea pig is simple-stomached; but in contrast to these species, the entire stomach of the guinea pig is lined with glandular epithelium (Breazile and Brown, 1976; Navia and Hunt, 1976). The intestine allows the development of predominantly gram-positive bacterial flora, which may contribute to the nutritional requirements of the host perhaps through direct absorption of bacterial metabolites or digestion and absorption of intestinal bacteria and other materials following coprophagy. The guinea pig has a large semicircular cecum with numerous lateral pouches. This organ resembles that of the rabbit and possibly has similar digestive functions—e.g., synthesis of B vitamins and indispensable amino acids by microorganisms and recycling of intestinal contents by coprophagy (Hunt and Harrington, 1974). Few serious attempts have been made to determine the contribution of coprophagy to the nutrition of the guinea pig.
The precise content of the data-sharing plan will vary, depending on the data being collected and how the investigator is planning to share the data. Applicants who are planning to share data may wish to describe briefly the expected schedule for data sharing, the format of the final dataset, the documentation to be provided, whether or not any analytic tools also will be provided, whether or not a data-sharing agreement will be required and, if so, a brief description of such an agreement (including the criteria for deciding who can receive the data and whether or not any conditions will be placed on their use), and the mode of data sharing (e.g., under their own auspices by mailing a disk or posting data on their institutional or personal Web site, through a data archive or enclave). Investigators choosing to share under their own auspices may wish to enter into a data-sharing agreement. References to data sharing may also be appropriate in other sections of the application.
Investigator/Mentor:Is the work proposed appropriate to the experience level of the doctoral candidate-investigator? Does the student show promise as a research investigator in areas relevant to the proposal? Is the proposed research project consistent with the long-term research interests of the applicant? Are the faculty advisor/dissertation chair and other doctoral committee members appropriately qualified to provide guidance as needed? Have the faculty advisor/dissertation chair and any other participating members of the committee indicated that they will provide sufficient time to allow completion of the dissertation? Will the faculty advisor/dissertation chair provide the necessary supervision and mentoring to the student?
Environment: Do(es) the scientific environment(s) in which the work will be done contribute to the probability of success? Do the proposed studies benefit from unique features of the scientific environment, or subject populations, or employ useful collaborative arrangements? Is there evidence of institutional support?