Popis: |
Summary 1. Two double-reversal trials involving four groups of five cows each were conducted simultaneously over a period of three 20-day periods. The effect of feeding limited and full feedings of hay to cows at midday while they were in the shade was tested while cows had access to excellent permanent pasture. The fact that the hay fed consisted of one-third grass (and two-thirds clover) may have caused the results to be quite different from those which might have been secured had all of the hay consisted of high quality clover. 2. Average change in production for the two groups used in determining the influence of limited hay feeding (0.5 per cent of body weight daily) was + 0.4 and −1.0 lb. of milk per cow daily. Daily hay consumption averaged 4.69 lb. per cow during periods fed hay. 3. The two groups on the full-hay feeding phase showed changes due to the hay supplementation averaging + 0.1 and −0.1 lb. per cow daily compared to check periods, and during periods fed hay consumed an average of 5.54 lb. per cow daily. Changes in milk yields due to feeding of hay proved insignificant and economically unprofitable. 4. No reduction for time spent grazing due to limited hay feeding could be found, although those on full feeding of hay grazed an average of 40 minutes per day less than during check periods without hay. This difference appeared to be due to chance variation rather than definitely to be caused by hay feeding. 5. Hay feeding failed to produce definite changes in body weights of cows other than those also shown by check groups not fed hay. 6. Grazing in daytime consisted of 1.49 hours in the sunshine and 0.4 hour in the shade. Time during day not grazing averaged 4.1 hours with cows standing or lying in shade, 1.03 hours lying in mud, and, for periods fed hay, 0.66 hour eating hay. 7. Activities at night averaged 4.7 hours actually grazing, 1.28 hours standing not grazing, and 3.52 hours lying down. |