Effect of Heavy Concentrate Feeding Before Calving Upon Lactation and Mammary Gland Edema

Heavy grain-feeding before calving resulted in no increase in the yield of fatcorrected milk during the first 84 days of lactation. Nine cows and nine heifers received, in addition to a basal roughage ration, a supplement of 378 and 273 lb. grain, respectively, during a 6-wk. prepartum period. A similar number of controls received no grain. During lactation all animals were fed roughage and grain according to maintenance and production requirements. Supplemented animals made significantly greater (P ----~ 0.01) increases in live weight but evidenced no significant increase in the incidence or severity of manmmry edema as determined by visual ratings and linear measurements. Heifers showed more edema at calving than did older cows.