Abstract #M384

# M384
Effects of intensive whole-milk feeding in calves on subsequent feeding behavior of dairy heifers.
Camila Flávia de Assis Lage1, Mariana Magalhães Campos2, Fernanda Samarini Machado2, Paulo Campos Martins1, Luigi Francis Lima Cavalcanti3, Marcelo Neves Ribas3, Luiz Gustavo Ribeiro Pereira2, Thierry Ribeiro Tomich2, Rafael Alves de Azevedo*1, Sandra Gesteira Coelho1, 1Federal University of Minas Gerais, Belo Horizonte, MG, Brazil, 2EMBRAPA Dairy Cattle, Coronel Pacheco, Minas GG, Brazil, 3CNPq, RHAE–SEVA Engenharia, Projeto Intergado, Contagem, MG, Brazil.

This study aimed to evaluate the effects of intensive whole milk feeding in calves on subsequent feeding behavior of 58 Holstein-Gyr females. Up to 56 d of age, calves received 6 L/d of 4 different liquid diets consisting of whole milk with the increasing addition of milk replacer (Sprayfo Violet SSP) to adjust the concentration of total solids (TS) to 13.5 (n = 15), 16.1 (n = 15), 18.2 (n = 13), 20.4% (n = 15). After weaning, animals were randomly housed in 4 paddocks, each one equipped with 3 electronic feed bins and one electronic water bin (INTERGADO, Brazil) in Embrapa Dairy Cattle facilities, Brazil. The diet (70% corn silage and 30% concentrate, 195 g of CP/kg, DM basis) was fed ad libitum, twice a day, until 210 d of age. Only events with registered intake were used, and the following results were calculated: Ingestion rate (IR, g/s), average bunk visit duration (AVD, min), daily visit duration (DVD, h) and daily visit frequency (VF, events). Due to the natural right skewness of IR and AVD distributions, their daily median, instead of mean, were used to represent their trends across study period. All variables were analyzed as a completely randomized design with repeated measures using linear mixed model approach. Age and TS were evaluated as fixed effects, while animals as random. The necessity to model error dependence and heteroscedasticity was evaluated by monitoring Schwarz criterion. The effect of TS was decomposed into orthogonal polynomials of linear and quadratic degrees. Significance was declared at P < 0.05. All variables were consistently influenced by animal’s age, where IR was increased as animals become older (0.837 ± 0.075 g/s at 100 d old versus 1.617 ± 0.072 g/s at 210 d old). An interaction effect between TS and age was detected for IR, where TS linear increased IR for animals older than 190 d of age. None of visit variables were affected by TS levels (AVD = 3.70 ± 0.37 min, DVD = 2.50 ± 0.12 h, VF = 35.16 ± 3.21 events). Intensive whole-milk feeding in calves caused minor effects on subsequent feeding behavior of dairy heifers.

Key Words: milk replacer, intake, precision farming