Abstract #431

# 431
Early postnatal plane of nutrition of Holstein calves has an effect on milk production and feed intake during their first lactation.
Steffi Wiedemann*1, Patricia Holz2, Hans-Juergen Kunz3, Martin Kaske4, 1Animal Health, Institute of Animal Breeding and Husbandry, Kiel University, Kiel, Germany, 2Clinic for Cattle, University of Veterinary Medicine Hannover Foundation, Hannover, Germany, 3Chamber of Agriculture of Schleswig-Holstein, Blekendorf, Germany, 4Department for Farm Animals, University of Zurich, Zurich, Switzerland.

The objective of the study was to assess the effect of 2 different feeding strategies during the very early postnatal life of Holstein calves on subsequent first lactation milk production and feed intake. During the first 4 wk of life, calves were fed either ad libitum (AdL; ad libitum feeding of whole milk during wk 1 and milk replacer ([MR], 160 g/L) from d 8–28; n = 38) or according to a restrictive feeding protocol (RES; 4 L milk/d during wk 1, 6 L MR (120 g/L) from d 8–28; n = 30). Feeding was similar in both groups after the 4th wk of life. All animals were kept individually during the first wk of life and in groups thereafter. The feed intakes were analyzed during the first 10 wk of life in all animals and during first lactation in 37 animals. Daily milk yield and monthly milk composition were recorded. Total energy intake during the first 4 wk was higher in AdL-calves compared with RES-calves (16.6 MJ ME/d vs. 10.2 MJ ME/d, respectively; P < 0.01). Thereafter, no difference in energy intake was observed until the 10th wk of life. In AdL-calves the average daily gain was higher compared with RES-calves during the first 4 wk of life (0.72 vs. 0.45 kg/d; P < 0.001), while age at first calving did not differ (765 vs. 777 d; P = 0.30). In the AdL- and RES-group, 21 and 26 animals remained on the farm for a full 305-d first lactation, respectively. The FCM yield was higher in AdL-animals compared with RES-animals (29.2 ± 0.4 vs. 28.0 ± 0.4 kg FCM/d; P < 0.05); but milk composition did not differ. The higher FCM yield was accompanied by a higher feed intake in AdL-animals (19.3 kg DM/d vs. 18.8 kg DM/d; P < 0.01). The results indicate that an increased feeding intensity during early life has positive long-term effects on the milk production potential in the first lactation, which could be the result of an improved girth or height or of an enhanced development of mammary parenchyma.

Key Words: calf feeding, feed intake, milk production