Adult female mink were fed diets containing 0 (control), 6.25, 12.5, and 25 ppm (micrograms/g) technical grade heptachlor prior to and throughout the reproductive period (181 days) to evaluate the effects of heptachlor consumption on reproduction and offspring viability and to assess the extent of placental and mammary transfer of heptachlor epoxide to mink offspring. Feeding 12.5 and 25 ppm resulted in significant reductions in feed consumption and body weights of female mink. Mortality was 0, 8, 67, and 100% for the control, 6.25, 12.5, and 25 ppm groups, respectively. All females in the 25 ppm group died within 88 days. Mink fed the two higher heptachlor diets displayed clinical signs indicative of central nervous system involvement just prior to death. Females were mated with males on the same dietary treatments. Whelping success rates were 67, 83, 27, and 0% for the control, 6.25, 12.5, and 25 ppm groups, respectively. High mortality in the 12.5 and 25 ppm groups accounted for the lack of reproductive success. Gestation length, litter size and birth weight of kits were not significantly affected by adult female consumption of 6.25 ppm heptachlor while kits helped by females on the 12.5 ppm diet weighed significantly less than control kits at birth. Survival of kits in the 12.5 ppm group from birth to three weeks of age was also adversely affected. At three and six weeks of age, kit body weights in both the 6.25 and 12.5 ppm groups were significantly less than body weights in control kits.(ABSTRACT TRUNCATED AT 250 WORDS)

The turfgrass program at Michigan State University has recently dedicated and focused its research on sports turf management. There are three major areas of research: (1) the indoor turfgrass project, (2) the use of crumb rubber from used tires, and (3) management of high sand-based root zone athletic fields. The indoor turf project stemmed from the 1994 World Cup Soccer Matches involving the installation and maintenance of a portable turfgrass system in the Pontiac Silverdome in Pontiac, Michigan. The majority of the research for this project was completed in a 600-m2 dome constructed on the Michigan State University campus specifically for this project. The crumb rubber project was initiated in 1990 and nine experiments were used to investigate the incorporation of crumb rubber from used tires into the soil profile and at the turf-soil interface of turf systems to improve turfgrass wear tolerance and reduce soil compaction. The sand-based root zone turf project was initiated in 1992 to investigate establishment and management scenarios specific to these areas. A 334-m2 field was constructed to investigate these practices. Initial studies dealt with the establishment of either Kentucky bluegrass (Poa pratensis L.) or perennial ryegrass (Lolium perenne L.) with different fertilizer management regimes.

Adult female mink previously fed diets containing 0 (control) and 6.25 mg heptachlor/kg diet for 181 days were fed either the same control diet ad libitum (AL) or the control diet containing 10% mineral oil and restricted by 45% of ad libitum intake (MO/R) for 21 days to determine the efficacy of the latter treatment in enhancing the elimination of heptachlor epoxide (HE) from mink. Kit mink (2-3 months of age) whelped by dams of the control and 6.25 mg/kg groups were also fed the MO/R or AL diets for 21 days. Daily consumption (g/kg bw/day) of the AL diet by kit mink was significantly greater than consumption of the same diet by the adult females. Body weights of the control adults and the control and 6.25 mg/kg kits were significantly reduced by feeding the MO/R diet. Two adults from the control group and one adult from the 6.25 mg/kg group fed the MO/R diet died during the 21-day period. No mortalities occurred in kit mink fed either diet. Administration of the MO/R diet caused a significant reduction in body fat of the control adults and kits, but not in the 6.25 mg/kg adults and kits. Decreases in body fat of the MO/R groups were not associated with greater elimination of HE when compared to the AL groups.(ABSTRACT TRUNCATED AT 250 WORDS)