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CHEMICAL load of nitrate-plus nitrite-nitrogen and orthophosphate-phosphorus in runoff from a complex cover agricultural watershed in the Georgia Coastal Plain was found to be less than the rainfall input of these chemicals. Chloride load in runoff exceeded chloride load in rainfall. Measured stream flow nutrient losses showed a range in nitrate-plus nitrite-nitrogen load from 0.14 to 0.24 kg/ha/yr and a range in the orthophosphate-phosphorus load from 0.141 to 0.144 kg/ha/yr.

SEDIMENT delivery ratios (SDR) were computed for a 1736 ha, mixed land use, agricultural Coastal Plain watershed, based on observed sediment yield and com-puted gross erosion by the USLE method and an experi-mentally determined soil erodibility factor. Seasonal variation in SDR values was observed. This variation was not adequately explained by seasonal variation in rainfall and/or runoff. Relationships for predicting SDR based on season and climatic variables were developed for the study area. Season was found to be the predominate in-dividual predictor of observed variations in SDR values.

GROWING-FINISHING pigs were housed on either solid concrete floors or pre-cast concrete flushing slats in an open sided, naturally ventilated building. No differences in performance were observed during summer, but pigs housed on flushing slats had lower daily gains and required more feed per unit of gain than pigs on solid floors during winter. Measurement of foot dimensions revealed that pigs housed on flushing slats had slightly longer hooves and slightly longer and wider volar surfaces, and more uniform toe size than pigs housed on solid floors. Counts and evaluations of injuries indicated that the flushing slats were equal or superior to the solid concrete floors as related to feet and leg health of growing-finishing swine.

Forty-three gilts and 24 sows were tethered throughout gestation, and one-half were forced to walk on a treadmill 15 min daily 5 days a week. Exercised and nonexercised dams farrowed 10.0 and 10.2 pigs (P greater than .05) and weaned 8.1 and 7.9 (P greater than .05), respectively. Birth weight of pigs born alive from exercised and nonexercised dams averaged 1.6 and 1.5 kg (P greater than .05); weaning weights were 8.5 and 8.2 kg (P greater than .05), respectively. Sows farrowed 12% more pigs (P less than .05) than gilts and weaned 17% more pigs (P less than .05) that were 12% heavier at birth (P less than .01) than those of gilts. Forced exercise did not improve (P greater than .05) reproductive performance as measured by numbers of pigs farrowed and weaned or by birth and weaning weights. Mean length of gestation was not significantly affected by age of dam or exercise treatment. The interval between birth of first and birth of last pig per litter averaged 154 and 151 min (P greater than .05) for exercised gilts and sows, respectively, and 170 and 161 min (P greater than .05) for those not exercised.

PRE-CAST concrete flushing gang slats with tubes (6.9 cm diameter) formed in the concrete immediately below each slot were tested under laboratory and field conditions. Water velocity through the slats increased from 0.76 m/s at 1% slope to 0.90 m/s at 2.5% slope. For flushing with water pumped from a lagoon, 13.7 L/min/tube were required for either continuous or intermittent operation to keep the tubes clear. With a dosing siphon flush tank system a discharge rate of 0.7 L/s/tube for 20 s every 3 h cleaned the tubes. Excessive wintertime chilling of pigs housed on the slats in an open-sided building, compared to pigs on a solid concrete floor, was determined not to be due to the circulation of water through the slats.