Adin, G., Department of Animal Production, Extension Service, Ministry of Agriculture, Bet-Dagan, 7528809, Israel; Mabjeesh, S.J., Department of Animal Sciences, The Robert H. Smith Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, PO Box 12, Rehovot, 7610001, Israel;
This study aimed to identify individual characteristics differing among high-efficiency (HE; upper 20%, n = 31), low-efficiency (LE; lower 20%, n = 31), and mid-efficiency (ME, 60% n = 93) lactating cows. Primiparous (37) and multiparous (118) high-producing milking cows at 30 to 180 d in milk were fed individually a low-roughage diet [31.6% of dry matter (DM)] for 4 wk. Daily average DM intake, rate of eating, visit duration, meal size, and daily rumination time were higher in LE compared with HE cows. On the other hand, HE cows exhibited higher digestibility of DM, crude protein, and neutral detergent fiber than the LE cows. Daily eating time was similar in the HE and LE groups and higher than that of the ME cows. Visit and meal frequency, average visit and meal duration, daily lying time, and pedometer activity were similar in the HE, LE, and ME groups. The HE cows produced 1.75% more milk, but similar energy-corrected milk compared with the LE cows. Milk fat and protein content were lower by 1.8 and 3.8%, respectively, in the HE cows than in the LE group. Body weight (BW) and BW gain were similar in the 3 efficiency groups. Diurnal distribution of DM intake showed 6 distinct major meals, each composed of 1.1 to 1.6 visits. Higher intake peaks (greater meal size) were found in the LE cows compared with the HE group. Daily DM intake was highly correlated (affected) with energy-corrected milk production (r = 0.61), BW (r = 0.4), eating rate (r = 0.57), and visit size (r = 0.54). Energy balance showed that the lower efficiency of the LE cows was attributed to their excess heat production and energy loss. © 2018 American Dairy Science Association
Adin, G., Department of Animal Production, Extension Service, Ministry of Agriculture, Bet-Dagan, 7528809, Israel; Mabjeesh, S.J., Department of Animal Sciences, The Robert H. Smith Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, PO Box 12, Rehovot, 7610001, Israel;
This study aimed to identify individual characteristics differing among high-efficiency (HE; upper 20%, n = 31), low-efficiency (LE; lower 20%, n = 31), and mid-efficiency (ME, 60% n = 93) lactating cows. Primiparous (37) and multiparous (118) high-producing milking cows at 30 to 180 d in milk were fed individually a low-roughage diet [31.6% of dry matter (DM)] for 4 wk. Daily average DM intake, rate of eating, visit duration, meal size, and daily rumination time were higher in LE compared with HE cows. On the other hand, HE cows exhibited higher digestibility of DM, crude protein, and neutral detergent fiber than the LE cows. Daily eating time was similar in the HE and LE groups and higher than that of the ME cows. Visit and meal frequency, average visit and meal duration, daily lying time, and pedometer activity were similar in the HE, LE, and ME groups. The HE cows produced 1.75% more milk, but similar energy-corrected milk compared with the LE cows. Milk fat and protein content were lower by 1.8 and 3.8%, respectively, in the HE cows than in the LE group. Body weight (BW) and BW gain were similar in the 3 efficiency groups. Diurnal distribution of DM intake showed 6 distinct major meals, each composed of 1.1 to 1.6 visits. Higher intake peaks (greater meal size) were found in the LE cows compared with the HE group. Daily DM intake was highly correlated (affected) with energy-corrected milk production (r = 0.61), BW (r = 0.4), eating rate (r = 0.57), and visit size (r = 0.54). Energy balance showed that the lower efficiency of the LE cows was attributed to their excess heat production and energy loss. © 2018 American Dairy Science Association